Monday, December 7, 2015

STRICTLY IN CONFIDENCE WHY WE DON'T TEST ANIMAL FEED FOR ANIMAL PROTEIN BSE TSE PRION

STRICTLY IN CONFIDENCE

 

EXTRACT FROM MINUTES OF SCIENTIFIC COMMITTEE MEETING HELD ON 29 SEPTEMBER 1994

 

BSE: S33/94

 

a) Sampling of Ruminant Feeding stuffs for Ruminant Protein:

 

The voluntary sampling‘ on farms with suspected cases of BSE had commenced on 1 July 1994. The ELISA technique detected the presence of ruminant meat and bone meal to a level of 0.25% in finished feeding stuffs. MAFF had released a pre-publication copy of a paper discussing this technique which had been developed at the VI Centre Luddington. It provided detail of the use of the technique in meat and bone meal. It did not, however, discuss the extension of the assay for use in compound feeding stuffs. At the request of UKASTA, MAFF was looking at making the service commercially available in order for individual compounders to do their own testing. MAFF estimated that the charge for such testing would be £35 per sample (plus VAT).

 

It was reported that Luddington was carrying out further work in identifying potential sources of interference, from individual raw materials, which might produce a false positive result It was understood that glutens were considered to present a particular problem. During a discussion the Committee suggested that the conditioning temperatures, in different mills, might have varying effects on the breakdown of proteins in animal feeding stuffs.

 

A number of sites where cross contamination between animal proteins and other types of raw materials might occur were identified. These included not only on-farm but in-store, in the country of origin, in boats, in transport as well as different points within the feed mill. It was noted, however, that it might be counter productive to stress these varying numbers and sites.

 

Concern was expressed that the MAFF had commenced on-farm testing without necessarily thinking through the consequences for the whole of the agricultural industry. Officials were aware that one course of action open to feed compounders was to stop using meat and bone meal in the manufacture of any feeding stuff. An alternative for the industry was the establishment of ruminant feed only Such a step would only be open to those companies with more than one manufacturing site.

 

Cont'd/...2

 

94/9.29/3.1

 

b)

 

-2-

 

A decision by the industry as a whole to stop using meat and bone meal would have cost implications for the whole livestock industry. Not only would there be poorer returns to beef producers but also higher raw material costs for compounders when producing pig and poultry feeding stuffs. There would also be the problem of disposing of the unwanted animal by-products. Thus, it was agreed that whatever the actual consequences the effect o:n the livestock industry as a whole would be very damaging.

 

Proposed Survey of Past a.nd Present Practices in Members Feed Mills:

 

A copy of the draft questionnaire was circulated to Committee members “Strictly in Confidence". This was designed to investigate the likelihood that feed produced after the introduction of the ruminant feed ban could have become contaminated with ruminant derived protein and whether the likelihood of contamination had changed over time. In discussing the contents, UKASTA had not given any indication, on behalf of members, that they wanted them to complete the questionnaire when finalised. MAFF had also been made fully aware of UKASTA's concern that information submitted in response to the questionnaire by individual companies might, at some future time, be subpoenaed by a Court. This would be in any case taken against the company by a farmer seeking compensation for BSE in his herd.

 

The Committee was advised that a member company was still in debate over a case concerning the Fowl Pest outbreak in 1984. Lawyers acting for poultry producers had. submitted subpoenas for relevant Ministry documents. MAFF Legal Department was looking at the papers and aimed to resist the subpoena. However, the outcome of this action would not be known until March 1995. At the very least, it was considered that compounders should not: complete the questionnaire until the outcome of the Fowl Pest discussions were known. It was also reported that another company had been recommended, by its legal advisors, not to complete the questionnaire.

 

At a scientific level, it was noted that the aim of the CVL was to explain why BABs had occurred. Unfortunately, in the investigations it was necessary to identify the name and address of individual mills on the questionnaire in order to reconcile information on BABs regarding feeding practices on farm. It would not be possible for questionnaires to be sent to the CVL via UKASTA on an anonymous basis. UKASTA was seeking guidance from the Association's solicitors on what powers MAFF might have to require completion of the questionnaire.

 

It was suggested that whilst the CVL was finalising details of the questionnaire UKASTA should co-operate. Thus members were asked to send to the Secretariat their comments on the contents of the questionnaire by mid-November. Views were particularly required on which questions were difficult and/ or impossible to answer both because they were

 

Cont'd/...3 94/9.29/3.2

 

-3-

 

impractical as well as being able to put individual companies in a vulnerable position. These were to be passed on to the CVL with a request for amendments and/ or detailed responses in time for the Committee to discuss at the December meeting. Members were asked to discuss the questionnaire with as few people as possible because of the sensitive nature of this subject.

 

Members were also asked to keep the Secretariat informed of the nature of any enquiries which MAFF officials might address to them. It was also noted, by one member company who no longer used meat and bone meal, that since taking such action they had not received any queries from MAFF.

 

C) Recent Legislation:

 

The MAFF was implementing the two EU Decisions agreed in May. The ban on the use of mammalian meat and bone meal in ruminant feedingstuffs was to be incorporated into the BSE Order. At the same time the SBO ban was to be extended to cover the thymus and intestines of calves less than six months of age.

 

The European legislation on the rendering industry introduced a processing time/ temperature combination based on the results of rendering trials which had achieved an 80-fold diminution of the BSE agent. The legislation was not due to be brought into operation until the end of 1994. It was, however, hoped that UK rendering plants could have their processes validated and thus be in compliance with the new legislation by the end of October. Although it was not possible to prove zero infectivity, MAFF considered that adherence to the new standards would be a huge step forward in the control of BSE.

 

The Ministry was also reviewing the SBO legislation in order to make it more straightforward an.d simple to operate. The Committee also noted that, because of the nature of the material concerned, it would be extremely difficult to enforce the legislation. Concern was expressed, therefore, that the Ministry might just be introducing controls on paper. Effective auditing of the legislation should be introduced; for example by weighing the amount of SBO's collected and comparing this against the number of animals slaughtered.

 

In the light of all these concerns, the Committee considered that an easy reaction would be for the feed industry to stop using meat and bone meal in the manufacture of any animal feeding stuff. However, whereas this would be relatively painless, if somewhat expensive, for the feed industry, it would have serious repercussions throughout the whole of the livestock industry. It would also beg the question as to why it was safe for humans to eat meat whilst the by-products of the butchery trade that we use to produce meat and bone meal were unsatisfactory for animals.

 

Cont'd/...4

 

94/9.29/3.3

 

-4-

 

d) Origins of BSE:

 

A transcript of the Radio 4 interview with Mr. Keith Meldrum, Chief Veterinary Officer, held on 22 September was circulated. This raised the possibility of BSE being of bovine as opposed to ovine origin. Clarification had, therefore, been sought from the CVL. The response was that it was not possible to dismiss the possibility that BSE was bovine in origin. However, it was more difficult to support such a theory given current knowledge whereby the BSE epidemic had seen a sudden increase in numbers in the mid 1980's. It was thus still considered that the epidemic was explained by :-

 

- High level of sheep numbers in the UK;

 

- A change in the rendering practices in the late 1970's which permitted infected ovine material to survive the production process;

 

- The recycling of bovine material in the cattle population.

 

For BSE to be solely of bovine origin there would have had to have been a high prevalence of infected animals prior to the mid—1980‘s and this was not seen. It was thus possible that there was an element of politics in the comments made by Mr. Meldrum and it was probably no coincidence that a report of possible BSE cases in northern Germany had emerged at about the same time.

 

Meeting with Minister:

 

The Committee was advised that if necessary the Association would request

 

a meeting with the Minister to outline members‘ concerns regarding BSE and associated matters.

 

94/9.29/3.4

 


 

TEXAS One sorghum DDGS sample out of 168 DG samples was contaminated with bovine spongiform encephalopathy, but the transmission route of the bovine spongiform encephalopathy agent could not be clearly defined.

 

J Food Prot. 2015 Oct;78(10):1861-9. doi: 10.4315/0362-028X.JFP-15-157.

 

Evaluation of Selected Nutrients and Contaminants in Distillers Grains from Ethanol Production in Texas.

 

Lee KM1, Herrman TJ2. Author information 1Office of the Texas State Chemist, Texas A&M AgriLife Research, Texas A&M University System, College Station, Texas 77841, USA. kml@otsc.tamu.edu. 2Office of the Texas State Chemist, Texas A&M AgriLife Research, Texas A&M University System, College Station, Texas 77841, USA.

 

Abstract

 

This study evaluated distillers grain (DG) by-products produced in different ethanol plants and supplemented in animal diets in Texas, based on samples analyzed from 2008 to 2014. The samples were assessed for concentration, occurrence, and prevalence of selected nutrients and contaminants. Protein and sulfur contents of DG were largely different between corn and sorghum by-products as well as wet distillers grain with solubles and dry distillers grain with solubles (DDGS), indicating a significant effect of grain feedstock and dry-grind process stream on DG composition and quality. Salmonella was isolated in 4 DDGS samples out of a total of 157 DG samples, a percentage (2.5%) that is much lower than the percentage of Salmonella-positive samples found in other feed samples analyzed during the same period. A small amount of virginiamycin residue was found in 24 corn DDGS, 1 corn wet distillers grain with solubles, and 2 sorghum DDGS samples out of 242 samples in total. One sorghum DDGS sample out of 168 DG samples was contaminated with bovine spongiform encephalopathy, but the transmission route of the bovine spongiform encephalopathy agent could not be clearly defined. The concentrations of aflatoxin and fumonisin DG by-products averaged 3.4 μg/kg and 0.7 mg/kg, respectively. Among contaminated corn DG samples, five DDGS samples for aflatoxin contained a higher concentration than the U.S. Food and Drug Administration action level for use in animal feed, whereas no sample for fumonisin was found above the action level. The study results raised some important issues associated with the quality and use of DG by-products, suggesting several approaches and strategies for their effective and safe use as a feed ingredient to promote animal and human health and welfare.

 

PMID: 26408135 [PubMed - in process]

 


 

Sunday, September 27, 2015

 

TEXAS CONFIRMATION OF BOVINE SPONGIFORM ENCEPHALOPATHY BSE TSE PRION IN ONE SAMPLE OF SORGHUM DDGS OUT OF 168 DG SAMPLES

 

 please note, the author of this study contacted me ;

 

 corrected to

 

 "One sorghum DDGS out of 168 DG samples was contaminated with animal protein prohibited for use in ruminant feed and was channeled to poultry feed."

 

 We requested the journal editor to correct some errors and the relevant statements, or to withdraw the article from the journal.

 


 

 Monday, October 26, 2015

 

FDA PART 589 -- SUBSTANCES PROHIBITED FROM USE IN ANIMAL FOOD OR FEED VIOLATIONS OFFICIAL ACTION INDICATED OIA UPDATE October 2015

 


 

Saturday, January 31, 2015

 

European red deer (Cervus elaphus elaphus) are susceptible to Bovine Spongiform Encephalopathy BSE by Oral Alimentary route

 


 

I strenuously once again urge the FDA and its industry constituents, to make it MANDATORY that all ruminant feed be banned to all ruminants, and this should include all cervids as soon as possible for the following reasons...

 

======

 

In the USA, under the Food and Drug Administrations BSE Feed Regulation (21 CFR 589.2000) most material (exceptions include milk, tallow, and gelatin) from deer and elk is prohibited for use in feed for ruminant animals. With regards to feed for non-ruminant animals, under FDA law, CWD positive deer may not be used for any animal feed or feed ingredients. For elk and deer considered at high risk for CWD, the FDA recommends that these animals do not enter the animal feed system.

 

***However, this recommendation is guidance and not a requirement by law.

 

======

 

31 Jan 2015 at 20:14 GMT

 

*** Ruminant feed ban for cervids in the United States? ***

 

31 Jan 2015 at 20:14 GMT

 


 

Friday, December 14, 2012

 

DEFRA U.K. What is the risk of Chronic Wasting Disease CWD being introduced into Great Britain? A Qualitative Risk Assessment October 2012

 

snip...

 

In the USA, under the Food and Drug Administration’s BSE Feed Regulation (21 CFR 589.2000) most material (exceptions include milk, tallow, and gelatin) from deer and elk is prohibited for use in feed for ruminant animals. With regards to feed for non-ruminant animals, under FDA law, CWD positive deer may not be used for any animal feed or feed ingredients. For elk and deer considered at high risk for CWD, the FDA recommends that these animals do not enter the animal feed system. However, this recommendation is guidance and not a requirement by law.

 

Animals considered at high risk for CWD include:

 

1) animals from areas declared to be endemic for CWD and/or to be CWD eradication zones and

 

2) deer and elk that at some time during the 60-month period prior to slaughter were in a captive herd that contained a CWD-positive animal.

 

Therefore, in the USA, materials from cervids other than CWD positive animals may be used in animal feed and feed ingredients for non-ruminants.

 

The amount of animal PAP that is of deer and/or elk origin imported from the USA to GB can not be determined, however, as it is not specified in TRACES. It may constitute a small percentage of the 8412 kilos of non-fish origin processed animal proteins that were imported from US into GB in 2011.

 

Overall, therefore, it is considered there is a __greater than negligible risk___ that (nonruminant) animal feed and pet food containing deer and/or elk protein is imported into GB.

 

There is uncertainty associated with this estimate given the lack of data on the amount of deer and/or elk protein possibly being imported in these products.

 

snip...

 

36% in 2007 (Almberg et al., 2011). In such areas, population declines of deer of up to 30 to 50% have been observed (Almberg et al., 2011). In areas of Colorado, the prevalence can be as high as 30% (EFSA, 2011). The clinical signs of CWD in affected adults are weight loss and behavioural changes that can span weeks or months (Williams, 2005). In addition, signs might include excessive salivation, behavioural alterations including a fixed stare and changes in interaction with other animals in the herd, and an altered stance (Williams, 2005). These signs are indistinguishable from cervids experimentally infected with bovine spongiform encephalopathy (BSE). Given this, if CWD was to be introduced into countries with BSE such as GB, for example, infected deer populations would need to be tested to differentiate if they were infected with CWD or BSE to minimise the risk of BSE entering the human food-chain via affected venison.

 

snip...

 

The rate of transmission of CWD has been reported to be as high as 30% and can approach 100% among captive animals in endemic areas (Safar et al., 2008).

 

snip...

 

In summary, in endemic areas, there is a medium probability that the soil and surrounding environment is contaminated with CWD prions and in a bioavailable form. In rural areas where CWD has not been reported and deer are present, there is a greater than negligible risk the soil is contaminated with CWD prion.

 

snip...

 

In summary, given the volume of tourists, hunters and servicemen moving between GB and North America, the probability of at least one person travelling to/from a CWD affected area and, in doing so, contaminating their clothing, footwear and/or equipment prior to arriving in GB is greater than negligible. For deer hunters, specifically, the risk is likely to be greater given the increased contact with deer and their environment. However, there is significant uncertainty associated with these estimates.

 

snip...

 

Therefore, it is considered that farmed and park deer may have a higher probability of exposure to CWD transferred to the environment than wild deer given the restricted habitat range and higher frequency of contact with tourists and returning GB residents.

 

snip...

 


 

IBNC Tauopathy or TSE Prion disease, it appears, no one is sure

 

Posted by flounder on 03 Jul 2015 at 16:53 GMT

 


 

*** Singeltary reply ; Molecular, Biochemical and Genetic Characteristics of BSE in Canada Singeltary reply ;

 


 

*** It also suggests a similar cause or source for atypical BSE in these countries. ***

 

Discussion: The C, L and H type BSE cases in Canada exhibit molecular characteristics similar to those described for classical and atypical BSE cases from Europe and Japan.

 

*** This supports the theory that the importation of BSE contaminated feedstuff is the source of C-type BSE in Canada.

 

*** It also suggests a similar cause or source for atypical BSE in these countries. ***

 

see page 176 of 201 pages...tss

 


 

P.97: Scrapie transmits to white-tailed deer by the oral route and has a molecular profile similar to chronic wasting disease and distinct from the scrapie inoculum

 

Justin Greenlee1, S Jo Moore1, Jodi Smith1, M Heather West Greenlee2, and Robert Kunkle1 1National Animal Disease Center; Ames, IA USA; 2Iowa State University; Ames, IA USA

 

The purpose of this work was to determine susceptibility of white-tailed deer (WTD) to the agent of sheep scrapie and to compare the resultant PrPSc to that of the original inoculum and chronic wasting disease (CWD). We inoculated WTD by a natural route of exposure (concurrent oral and intranasal (IN); n D 5) with a US scrapie isolate. All scrapie-inoculated deer had evidence of PrPSc accumulation. PrPSc was detected in lymphoid tissues at preclinical time points, and deer necropsied after 28 months post-inoculation had clinical signs, spongiform encephalopathy, and widespread distribution of PrPSc in neural and lymphoid tissues. Western blotting (WB) revealed PrPSc with 2 distinct molecular profiles. WB on cerebral cortex had a profile similar to the original scrapie inoculum, whereas WB of brainstem, cerebellum, or lymph nodes revealed PrPSc with a higher profile resembling CWD. Homogenates with the 2 distinct profiles from WTD with clinical scrapie were further passaged to mice expressing cervid prion protein and intranasally to sheep and WTD. In cervidized mice, the 2 inocula have distinct incubation times. Sheep inoculated intranasally with WTD derived scrapie developed disease, but only after inoculation with the inoculum that had a scrapie-like profile. The WTD study is ongoing, but deer in both inoculation groups are positive for PrPSc by rectal mucosal biopsy. In summary, this work demonstrates that WTD are susceptible to the agent of scrapie, 2 distinct molecular profiles of PrPSc are present in the tissues of affected deer, and inoculum of either profile readily passes to deer.

 


 

From: Terry S. Singeltary Sr.

 

Sent: Tuesday, December 01, 2015 5:05 PM

 

To: Terry Singeltary Sr.

 

Subject: Docket No. APHIS-2007-0127 Scrapie in Sheep and Goats Terry Singeltary Sr. Submission

 

*** Docket No. APHIS-2007-0127 Scrapie in Sheep and Goats Terry Singeltary Sr. Submission ***

 

Docket No. APHIS-2007-0127 Scrapie in Sheep and Goats

 

SUMMARY: We are reopening the comment period for our proposed rule that would revise completely the scrapie regulations, which concern the risk groups and categories established for individual animals and for flocks, the use of genetic testing as a means of assigning risk levels to animals, movement restrictions for animals found to be genetically less susceptible or resistant to scrapie, and recordkeeping requirements. This action will allow interested persons additional time to prepare and submit comments.DATES: The comment period for the proposed rule published on September 10, 2015 (80 FR 54660-54692) is reopened. We will consider all comments that we receive on or before December 9, 2015. ...

 


 


 


 

Comment from Terry Singeltary This is a Comment on the Animal and Plant Health Inspection Service (APHIS) Proposed Rule: Scrapie in Sheep and Goats

 

For related information, Open Docket Folder Docket folder icon

 

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Comment View document:Indeed, much science has changed about the Scrapie TSE prion, including more science linking Scrapie to humans. sadly, politics, industry, and trade, have not changed, and those usually trump sound science, as is the case with all Transmissible Spongiform Encephalopathy TSE Prion disease in livestock producing animals and the OIE. we can look no further at the legal trading of the Scrapie TSE prion both typical and atypical of all strains, and CWD all stains. With as much science of old, and now more new science to back this up, Scrapie of all types i.e. atypical and typical, BSE all strains, and CWD all strains, should be regulated in trade as BSE TSE PRION. In fact, I urge APHIS et al and the OIE, and all trading partners to take heed to the latest science on the TSE prion disease, all of them, and seriously reconsider the blatant disregards for human and animal health, all in the name of trade, with the continued relaxing of TSE Prion trade regulations through the 'NEGLIGIBLE BSE RISK' PROGRAM, which was set up to fail in the first place. If the world does not go back to the 'BSE RISK ASSESSMENTS', enhance, and or change that assessment process to include all TSE prion disease, i.e. 'TSE RISK ASSESSMENT', if we do not do this and if we continue this farce with OIE and the USDA et al, and the 'NEGLIGIBLE BSE RISK' PROGRAM, we will never eradicate the TSE prion aka mad cow type disease, they will continue to mutate and spread among species of human and animal origin, and they will continue to kill. ...

 

please see ;

 

O.05: Transmission of prions to primates after extended silent incubation periods: Implications for BSE and scrapie risk assessment in human populations

 

Emmanuel Comoy, Jacqueline Mikol, Valerie Durand, Sophie Luccantoni, Evelyne Correia, Nathalie Lescoutra, Capucine Dehen, and Jean-Philippe Deslys Atomic Energy Commission; Fontenay-aux-Roses, France

 

Prion diseases (PD) are the unique neurodegenerative proteinopathies reputed to be transmissible under field conditions since decades. The transmission of Bovine Spongiform Encephalopathy (BSE) to humans evidenced that an animal PD might be zoonotic under appropriate conditions. Contrarily, in the absence of obvious (epidemiological or experimental) elements supporting a transmission or genetic predispositions, PD, like the other proteinopathies, are reputed to occur spontaneously (atpical animal prion strains, sporadic CJD summing 80% of human prion cases). Non-human primate models provided the first evidences supporting the transmissibiity of human prion strains and the zoonotic potential of BSE. Among them, cynomolgus macaques brought major information for BSE risk assessment for human health (Chen, 2014), according to their phylogenetic proximity to humans and extended lifetime. We used this model to assess the zoonotic potential of other animal PD from bovine, ovine and cervid origins even after very long silent incubation periods.

 

*** We recently observed the direct transmission of a natural classical scrapie isolate to macaque after a 10-year silent incubation period,

 

***with features similar to some reported for human cases of sporadic CJD, albeit requiring fourfold longe incubation than BSE. Scrapie, as recently evoked in humanized mice (Cassard, 2014),

 

***is the third potentially zoonotic PD (with BSE and L-type BSE),

 

***thus questioning the origin of human sporadic cases. We will present an updated panorama of our different transmission studies and discuss the implications of such extended incubation periods on risk assessment of animal PD for human health.

 

===============

 

***thus questioning the origin of human sporadic cases***

 

===============

 


 

***This information will have a scientific impact since it is the first study that demonstrates the transmission of scrapie to a non-human primate with a close genetic relationship to humans. This information is especially useful to regulatory officials and those involved with risk assessment of the potential transmission of animal prion diseases to humans.

 

***This observation strengthens the questioning of the harmlessness of scrapie to humans, at a time when protective measures for human and animal health are being dismantled and reduced as c-BSE is considered controlled and being eradicated. Our results underscore the importance of precautionary and protective measures and the necessity for long-term experimental transmission studies to assess the zoonotic potential of other animal prion strains.

 


 

please see file attachment for full submission and recent science and my deep concerns on the TSE Prion disease... No documents available. AttachmentsView All (1) scrapie-usa-blogspot-com View Attachment:

 


 

***********OCTOBER 2015*************

 

*** PRION 2015 ORAL AND POSTER CONGRESSIONAL ABSTRACTS ***

 

THANK YOU PRION 2015 TAYLOR & FRANCIS, Professor Chernoff, and Professor Aguzzi et al, for making these PRION 2015 Congressional Poster and Oral Abstracts available freely to the public. ...Terry S. Singeltary Sr.

 

P.108: Successful oral challenge of adult cattle with classical BSE

 

Sandor Dudas1,*, Kristina Santiago-Mateo1, Tammy Pickles1, Catherine Graham2, and Stefanie Czub1 1Canadian Food Inspection Agency; NCAD Lethbridge; Lethbridge, Alberta, Canada; 2Nova Scotia Department of Agriculture; Pathology Laboratory; Truro, Nova Scotia, Canada

 

Classical Bovine spongiform encephalopathy (C-type BSE) is a feed- and food-borne fatal neurological disease which can be orally transmitted to cattle and humans. Due to the presence of contaminated milk replacer, it is generally assumed that cattle become infected early in life as calves and then succumb to disease as adults. Here we challenged three 14 months old cattle per-orally with 100 grams of C-type BSE brain to investigate age-related susceptibility or resistance. During incubation, the animals were sampled monthly for blood and feces and subjected to standardized testing to identify changes related to neurological disease. At 53 months post exposure, progressive signs of central nervous system disease were observed in these 3 animals, and they were euthanized. Two of the C-BSE animals tested strongly positive using standard BSE rapid tests, however in 1 C-type challenged animal, Prion 2015 Poster Abstracts S67 PrPsc was not detected using rapid tests for BSE. Subsequent testing resulted in the detection of pathologic lesion in unusual brain location and PrPsc detection by PMCA only. Our study demonstrates susceptibility of adult cattle to oral transmission of classical BSE. We are further examining explanations for the unusual disease presentation in the third challenged animal.

 


 

O.05: Transmission of prions to primates after extended silent incubation periods: Implications for BSE and scrapie risk assessment in human populations

 

Emmanuel Comoy, Jacqueline Mikol, Val erie Durand, Sophie Luccantoni, Evelyne Correia, Nathalie Lescoutra, Capucine Dehen, and Jean-Philippe Deslys Atomic Energy Commission; Fontenay-aux-Roses, France

 

Prion diseases (PD) are the unique neurodegenerative proteinopathies reputed to be transmissible under field conditions since decades. The transmission of Bovine Spongiform Encephalopathy (BSE) to humans evidenced that an animal PD might be zoonotic under appropriate conditions. Contrarily, in the absence of obvious (epidemiological or experimental) elements supporting a transmission or genetic predispositions, PD, like the other proteinopathies, are reputed to occur spontaneously (atpical animal prion strains, sporadic CJD summing 80% of human prion cases). Non-human primate models provided the first evidences supporting the transmissibiity of human prion strains and the zoonotic potential of BSE. Among them, cynomolgus macaques brought major information for BSE risk assessment for human health (Chen, 2014), according to their phylogenetic proximity to humans and extended lifetime. We used this model to assess the zoonotic potential of other animal PD from bovine, ovine and cervid origins even after very long silent incubation periods.

 

***We recently observed the direct transmission of a natural classical scrapie isolate to macaque after a 10-year silent incubation period, with features similar to some reported for human cases of sporadic CJD, albeit requiring fourfold longe incubation than BSE.

 

***Scrapie, as recently evoked in humanized mice (Cassard, 2014), is the third potentially zoonotic PD (with BSE and L-type BSE),

 

***thus questioning the origin of human sporadic cases. We will present an updated panorama of our different transmission studies and discuss the implications of such extended incubation periods on risk assessment of animal PD for human health.

 

===============

 

***thus questioning the origin of human sporadic cases...

 

===============

 


 

***Our study demonstrates susceptibility of adult cattle to oral transmission of classical BSE. ***

 

***our findings suggest that possible transmission risk of H-type BSE to sheep and human. ***

 

P.86: Estimating the risk of transmission of BSE and scrapie to ruminants and humans by protein misfolding cyclic amplification

 

Morikazu Imamura, Naoko Tabeta, Yoshifumi Iwamaru, and Yuichi Murayama National Institute of Animal Health; Tsukuba, Japan

 

To assess the risk of the transmission of ruminant prions to ruminants and humans at the molecular level, we investigated the ability of abnormal prion protein (PrPSc) of typical and atypical BSEs (L-type and H-type) and typical scrapie to convert normal prion protein (PrPC) from bovine, ovine, and human to proteinase K-resistant PrPSc-like form (PrPres) using serial protein misfolding cyclic amplification (PMCA).

 

Six rounds of serial PMCA was performed using 10% brain homogenates from transgenic mice expressing bovine, ovine or human PrPC in combination with PrPSc seed from typical and atypical BSE- or typical scrapie-infected brain homogenates from native host species. In the conventional PMCA, the conversion of PrPC to PrPres was observed only when the species of PrPC source and PrPSc seed matched. However, in the PMCA with supplements (digitonin, synthetic polyA and heparin), both bovine and ovine PrPC were converted by PrPSc from all tested prion strains. On the other hand, human PrPC was converted by PrPSc from typical and H-type BSE in this PMCA condition.

 

Although these results were not compatible with the previous reports describing the lack of transmissibility of H-type BSE to ovine and human transgenic mice, ***our findings suggest that possible transmission risk of H-type BSE to sheep and human. Bioassay will be required to determine whether the PMCA products are infectious to these animals.

 

================

 


 


 

==========================================

 

***our findings suggest that possible transmission risk of H-type BSE to sheep and human. Bioassay will be required to determine whether the PMCA products are infectious to these animals.

 

==========================================

 

It also appears to Mr MacLean that Mr Bradley’s answer (that it would take less than say 100 grams) was probably given with the benefit of hindsight: particularly if one considers that later in the same answer Mr Bradley expresses his surprise that it could take as little of 1 gram of brain to cause BSE by the oral route within the same species. This information did not become available until the “attack rate” experiment had been completed in 1995/96. This was a titration experiment designed to ascertain the infective

 

2

 

dose. A range of dosages was used to ensure that the actual result was within both a lower and an upper limit within the study and the designing scientists would not have expected all the dose levels to trigger infection. The dose ranges chosen by the most informed scientists at that time ranged from 1 gram to three times one hundred grams. It is clear that the designing scientists must also have shared Mr Bradley’s surprise at the results because all the dose levels right down to 1 gram triggered infection.

 

It is clear that the designing scientists must also have shared Mr Bradleys surprise at the results because all the dose levels right down to 1 gram triggered infection.

 


 

it is clear that the designing scientists must have also shared Mr Bradleys surprise at the results because all the dose levels right down to 1 gram triggered infection.

 


 

Saturday, September 12, 2015

 

The Canadian Management of Bovine Spongiform Encephalopathy in Historical and Scientific Perspective, 1990-2014

 

>>>We propose that Canadian policies largely ignored the implicit medical nature of BSE, treating it as a purely agricultural and veterinary issue. In this way, policies to protect Canadians were often delayed and incomplete, in a manner disturbingly reminiscent of Britain’s failed management of BSE. Despite assurances to the contrary, it is premature to conclude that BSE (and with it the risk of variant Creutzfeldt-Jakob disease) is a thing of Canada’s past: BSE remains very much an issue in Canada’s present. <<<

 


 

small amount of leftover contaminated feed’ ...LOL...maybe large amount in USA. see ;

 

Monday, November 30, 2015

 

*** Report on the Investigation of the Nineteenth Case of Bovine Spongiform Encephalopathy (BSE) in Canada November 2015 ***

 


 

Wednesday, September 23, 2015

 

NIH Availability for Licensing AGENCY: [FR Doc. 2015–24117 Filed 9–22–15; 8:45 am] Detection and Discrimination of Classical and Atypical L-Type BSE Strains by RT-QuIC

 


 

10 years post mad cow feed ban August 1997

 

10,000,000+ LBS. of PROHIBITED BANNED MAD COW FEED I.E. BLOOD LACED MBM IN COMMERCE USA 2007

 

Date: March 21, 2007 at 2:27 pm PST

 

RECALLS AND FIELD CORRECTIONS: VETERINARY MEDICINES -- CLASS II

 

PRODUCT

 

Bulk cattle feed made with recalled Darling's 85% Blood Meal, Flash Dried, Recall # V-024-2007

 

CODE

 

Cattle feed delivered between 01/12/2007 and 01/26/2007

 

RECALLING FIRM/MANUFACTURER

 

Pfeiffer, Arno, Inc, Greenbush, WI. by conversation on February 5, 2007.

 

Firm initiated recall is ongoing.

 

REASON

 

Blood meal used to make cattle feed was recalled because it was cross- contaminated with prohibited bovine meat and bone meal that had been manufactured on common equipment and labeling did not bear cautionary BSE statement.

 

VOLUME OF PRODUCT IN COMMERCE

 

42,090 lbs.

 

DISTRIBUTION

 

WI

 

___________________________________

 

PRODUCT

 

Custom dairy premix products: MNM ALL PURPOSE Pellet, HILLSIDE/CDL Prot- Buffer Meal, LEE, M.-CLOSE UP PX Pellet, HIGH DESERT/ GHC LACT Meal, TATARKA, M CUST PROT Meal, SUNRIDGE/CDL PROTEIN Blend, LOURENZO, K PVM DAIRY Meal, DOUBLE B DAIRY/GHC LAC Mineral, WEST PIONT/GHC CLOSEUP Mineral, WEST POINT/GHC LACT Meal, JENKS, J/COMPASS PROTEIN Meal, COPPINI - 8# SPECIAL DAIRY Mix, GULICK, L-LACT Meal (Bulk), TRIPLE J - PROTEIN/LACTATION, ROCK CREEK/GHC MILK Mineral, BETTENCOURT/GHC S.SIDE MK-MN, BETTENCOURT #1/GHC MILK MINR, V&C DAIRY/GHC LACT Meal, VEENSTRA, F/GHC LACT Meal, SMUTNY, A- BYPASS ML W/SMARTA, Recall # V-025-2007

 

CODE

 

The firm does not utilize a code - only shipping documentation with commodity and weights identified.

 

RECALLING FIRM/MANUFACTURER

 

Rangen, Inc, Buhl, ID, by letters on February 13 and 14, 2007. Firm initiated recall is complete.

 

REASON

 

Products manufactured from bulk feed containing blood meal that was cross contaminated with prohibited meat and bone meal and the labeling did not bear cautionary BSE statement.

 

VOLUME OF PRODUCT IN COMMERCE

 

9,997,976 lbs.

 

DISTRIBUTION

 

ID and NV

 

END OF ENFORCEMENT REPORT FOR MARCH 21, 2007

 


 

16 years post mad cow feed ban August 1997

 

2013

 

Sunday, December 15, 2013

 

FDA PART 589 -- SUBSTANCES PROHIBITED FROM USE IN ANIMAL FOOD OR FEED VIOLATIONS OFFICIAL ACTION INDICATED OIA UPDATE DECEMBER 2013 UPDATE

 


 

17 years post mad cow feed ban August 1997

 

Tuesday, December 23, 2014

 

FDA PART 589 -- SUBSTANCES PROHIBITED FROM USE IN ANIMAL FOOD OR FEED VIOLATIONS OFFICIAL ACTION INDICATED OAI UPDATE DECEMBER 2014 BSE TSE PRION

 


 

Monday, October 26, 2015

 

FDA PART 589 -- SUBSTANCES PROHIBITED FROM USE IN ANIMAL FOOD OR FEED VIOLATIONS OFFICIAL ACTION INDICATED OIA UPDATE October 2015

 


 

Sunday, June 14, 2015

 

Larry’s Custom Meats Inc. Recalls Beef Tongue Products That May Contain Specified Risk Materials BSE TSE Prion

 


 

Evidence That Transmissible Mink Encephalopathy Results from Feeding Infected Cattle

 

Over the next 8-10 weeks, approximately 40% of all the adult mink on the farm died from TME.

 

snip...

 

The rancher was a ''dead stock'' feeder using mostly (>95%) downer or dead dairy cattle...

 


 

In Confidence - Perceptions of unconventional slow virus diseases of animals in the USA - APRIL-MAY 1989 - G A H Wells

 

3. Prof. A. Robertson gave a brief account of BSE. The US approach was to accord it a very low profile indeed. Dr. A Thiermann showed the picture in the ''Independent'' with cattle being incinerated and thought this was a fanatical incident to be avoided in the US at all costs. ...

 


 

spontaneous atypical BSE ???

 

don’t let anyone fool you. spontaneous TSE prion disease is a hoax in natural cases, never proven.

 

all one has to do is look at France. France is having one hell of an epidemic of atypical BSE, probably why they stopped testing for BSE, problem solved $$$ same as the USA, that’s why they stopped testing for BSE mad cow disease in numbers they could find any with, after those atypical BSE cases started showing up. shut down the testing to numbers set up by OIE that are so low, you could only by accident find a case of BSE aka mad cow disease. and this brilliant idea by the WHO et al, to change the name of mad cow disease, thinking that might change things is preposterous. it’s all about money now folks, when the OIE, USDA and everyone else went along and made the TSE prion disease aka mad cow type disease a legal trading commodity by the BSE MRR policy, I would say everyone bit off more then they can chew, and they will just have to digest those TSE Prions coming from North America, and like it, and just prey you don’t get a mad cow type disease i.e. Transmissible Spongiform Encephalopathy TSE prion disease in the decades to come, and or pass it to some other poor soul via the iatrogenic medical surgical tissue friendly fire mode of transmission i.e. second hand transmission. it’s real folks, just not documented much, due to lack of trace back efforts. all iatrogenic cjd is, is sporadic cjd, until the iatrogenic event is tracked down and documented, and put into the academic and public domain, which very seldom happens. ...

 

As of December 2011, around 60 atypical BSE cases have currently been reported in 13 countries, *** with over one third in France.

 


 

***atypical spontaneous BSE in France LOL***

 

FRANCE STOPS TESTING FOR MAD COW DISEASE BSE, and here’s why, to many spontaneous events of mad cow disease $$$

 

***so 20 cases of atypical BSE in France, compared to the remaining 40 cases in the remaining 12 Countries, divided by the remaining 12 Countries, about 3+ cases per country, besides Frances 20 cases. you cannot explain this away with any spontaneous BSe. ...TSS

 

Sunday, October 5, 2014

 

France stops BSE testing for Mad Cow Disease

 


 

Sunday, October 18, 2015

 

World Organisation for Animal Health (OIE) and the Institut Pasteur Cooperating on animal disease and zoonosis research

 


 

 

Terry S. Singeltary Sr.

Monday, November 30, 2015

Report on the Investigation of the Nineteenth Case of Bovine Spongiform Encephalopathy (BSE) in Canada November 2015

Report on the Investigation of the Nineteenth Case of Bovine Spongiform Encephalopathy (BSE) in Canada


November 2015

 

Report on the Investigation of the Nineteenth Case of Bovine Spongiform Encephalopathy (BSE) in Canada


November 2015

Table of Contents



List of Tables


Table 1. Commercially Prepared Feed Sources to Which the Case Animal had Potentially been Exposed
Table 2. Rendered Animal By-Products Sources to Which the Case Animal had Potentially been Exposed
Table 3. Disposition of Animal Traces for BSE #19 Birth Cohort (n=746)

List of Figures


Figure 1. Sources, Processing, Transportation and Disposal of SRMs
Figure 2. Timeline (birth and death) of BSE Cases #17 and #19 Born on the Same Farm

Acronyms


BAB
Born After the Ban
BARB
Born After the Reinforced Ban
BSE
Bovine Spongiform Encephalopathy
CFIA
Canadian Food Inspection Agency
EFB
Enhanced Feed Ban
ISO
International Organization for Standardization
MBM
Meat and Bone Meal
OIE
World Organisation for Animal Health
PM
Prohibited Material
QA
Quality Assurance
SRM
Specified Risk Material
TSE
Transmissible Spongiform Encephalopathies

1.0 Introduction


1.1 Details of the BSE Case


A sample taken from a cow in Alberta, Canada was identified as positive for Bovine Spongiform Encephalopathy (BSE). The case animal was reported by the owner to have been non-ambulatory (downer) in the days preceding its death. After consultation between the producer and the local veterinary practitioner it was determined that the animal met the inclusion criteria of Canada's National BSE Surveillance Program. The animal was euthanized on February 4, 2015 and arrangements were made to collect and submit appropriate tissue samples for evaluation.

On February 7, 2015, the Alberta Agriculture Edmonton Laboratory (now Alberta Agriculture and Forestry TSE Laboratory) informed the Canadian Food Inspection Agency (CFIA) of a BSE surveillance sample (collected through the Canada-Alberta BSE Surveillance Program) with an initial reaction on the BIO-RAD TeSeE ELISA rapid test that remained positive on repeat testing.

As per Transmissible Spongiform Encephalopathies (TSE) ISO quality assurance (QA) guidelines, homogenates and samples were forwarded to the CFIA and OIE (World Organisation for Animal Health) BSE Reference Laboratory in Lethbridge, Alberta. The sample was confirmed as BSE positive using the OIE Immunoblot (SAF and mAB 6H4) test on February 11, 2015. In addition to the OIE Immunoblot, the National BSE Reference Laboratory evaluated the sample using the Prionics-Check Western® rapid test, Hybrid Western Blot, the Prionics Check PrioSTRIP® rapid test, and the BioRad TeSeE ELISA. All test results were determined to be positive. Hybrid Western Blot results characterized the case as C-type (classical) BSE.

The carcass was secured at the sampling site, obtained by and transferred to CFIA's laboratory in Lethbridge for incineration. No part of the carcass entered the human food supply or animal feed chain.

The positive animal (Case #19) was confirmed to be a pure bred Black Angus beef cow born on March 25, 2009, therefore being 70 months of age at the time of death. It had been sold from its birth farm, via an auction mart, to the farm where it was sampled, just over a year prior to detection (Jan 22, 2014). This was the second BSE case born on the birth farm (the previous was case #17, born in March 2004).

The birth farm of the case animal was a cow-calf operation with both purebred Black Angus and commercial beef cattle. At the time of detection of this case, there were 290 breeding cows on the birth farm.

1.2 Case Investigation Overview


1.2.1 CFIA Investigation as Specified by the OIE


The CFIA immediately initiated an epidemiological investigation based on the recommended BSE guidelines (Terrestrial Animal Health Code 2014) of the OIE and the CFIA's BSE Manual of Procedures. Specifically, the CFIA followed the recommended BSE guidelines for a country with controlled risk status and investigated:

  • Feed: all sources of feed to which the infected animal was or may have been exposed during its first year of life;
  • Feed cohort: all cattle which, during their first year of life, were reared with the BSE case during its first year of life, and which investigation showed consumed the same potentially contaminated feed during that period; and/or
  • Birth cohort: all other cattle that were born on the same farm and within 12 months of the infected animal's birth.

1.2.2 Identifying Potential Risk Pathways for Exposure to the BSE agent


BSE case #19 had two unique characteristics when compared with previous cases Canada has experienced to date:

  • This was the second BSE case to be born on the same birth farm (as was case #17, born in March 2004). Canada has not previously identified more than one BSE case born on the same farm.
  • The affected animal was born after the enhanced feed ban (EFB): The EFB, implemented on July 12, 2007, ensures that specified risk material (SRM) is excluded from animal feed, pet food and fertilizers. Case #19 was born in March 2009, which is 20 months after the EFB was implemented.

To complete this investigation, on-farm and off-farm risks pathways potentially associated with the unique characteristics of this case were examined. The following sections provide an overview of Canada's feed ban and the potential risk pathways that were considered in the course of the investigation.

1.3 Overview of Canada's Feed Ban and Regulations


In 1997, Canada implemented an initial feed ban as a precautionary measure to limit the potential spread of BSE through the domestic cattle population, should there have been a previously undetected presence of BSE in the country. This ban prohibited the feeding of mammalian-derived proteins (“prohibited material” or PM) to ruminant animals (cattle, sheep, goats, deer, elk and other species), with the exception of proteins derived from a porcine or equine; gelatin or gelatin products derived exclusively from hides or skins of any species; blood or blood products and rendered fats from any speciesFootnote 1. Canada's ban also prohibited incorporation of poultry litter and restaurant waste into feed for ruminants.

The detection of Canada's first native-born case of BSE in 2003, followed by a small number of BSE cases between 2003 and 2005 were a manifestation of a low level of exposure to the BSE-agent in the cattle population prior to and around the time the feed ban was implemented. In 2006, the Canadian Food Inspection Agency (CFIA) undertook a comprehensive review of the feed ban in order to look at the control measures put in place and examine the CFIA's inspection program to assess compliance with the Health of Animals Regulations. Canadian, U.S. and other international scientific and technical analyses, including a review of the UK experience, confirmed that the ban would have arrested any further amplification and significantly reduced the opportunities for recycling of the BSE-agent in the cattle population. While the impact of the feed ban may not have been absolute, ongoing surveillance confirms the low and declining incidence of BSE. Multiple scientific analyses have concluded that Canada's feed ban would eventually lead to the eradication of BSE in the countryFootnote 2Footnote 3. However, Canada decided to take the additional step necessary to accelerate this process by requiring that SRM be excluded from the entire terrestrial and aquatic animal feed chains, as well as fertilizers from July 2007. It is important to note that prior to 2007, SRM were prohibited from being fed to ruminants as they fell under the scope of the original feed ban as prohibited materials. SRM are now segregated at source and redirected to disposal or destruction to ensure that the remaining PM no longer contains SRM.

SRM includes the skull, brain, trigeminal ganglia, eyes, tonsils, spinal cord and dorsal root ganglia of cattle aged 30 months or older, and the distal ileum of cattle of all ages. Collectively these tissues contain more than 99.9% of the BSE infectivity in an infected animal. Considering that any remaining potential infectivity in non-SRM tissues would be at extremely low levels, the likelihood of an animal becoming infected would be negligible even if it consumed feed contaminated with PM.

Preventing SRM from entering the animal feed and pet food production chain enhanced the 1997 feed ban by minimizing the risk of BSE transmission posed by the cross-contamination of ruminant feed by PM, as well as any inappropriate on-farm use. The provision to prohibit the use of SRM in fertilizers was intended to prevent the potential accidental or intentional misuse of fertilizers as feed.

SRM is collected, segregated, stained, and directed to a dedicated line/container. Collection, treatment, transport and disposal of SRM are done under a permitting systemFootnote 4. The SRM program is implemented, administered, monitored and enforced by the CFIA through inspection activities at dead stock collection sites, salvaging and rendering facilities, landfills, and other processing and disposal sites.

SRM collected for processing and disposal is predominantly sourced from slaughterhouses and on-farm bovine dead stock (Figure 1).  Compliance verification programs of the measures in place to ensure the SRM ban is effective are detailed in Appendix 1.
Figure 1. Sources, Processing, Transportation and Disposal of SRMs
Sources, Processing, Transportation and Disposal of SRMs. Description follows.
The image illustrates how Specified Risk Material (SRM) comes predominantly from slaughterhouses and on-farm bovine dead stock and is collected for disposal. SRM is not permitted to enter the human food and animal feed supply.

1.4 Pathways for On-farm Exposure to the BSE Agent Associated with BSE Case #19


1.4.1 Residual Feed Contamination on Farm


The extensive UK experience with BSE led to the conclusion that the ingestion of contaminated feed remains the most likely source of BSE in infected animals born after the implementation of a feed banFootnote 5.

With two BSE cases diagnosed on the same birth farm the investigation of possible residual feed contamination on farm was conducted. The first case (BSE case #17) was born when the 1997 feed ban was in place, prior to enhancements to exclude SRM (Figure 2). While the second case (BSE case #19) was born 20 months after the enhanced feed ban was implemented, it is possible that small amounts of residual contaminated feed associated with the previous case could have remained on the farm Footnote 6. It is important to note that while the previous case (#17) most likely became infected in 2004, it did not arise as a BSE case until February 2010, almost a year after the birth of the case under consideration.

1.4.2 Maternal transmission


The report of the meeting of the OIE ad hoc group to review the BSE chapter in the OIE Terrestrial animal health code (2006) concluded that there was no evidence that vertical transmission of the BSE agent occurs. In this particular case, it has been determined that case #17 (commercial cow) is not the dam of case #19 (pure bred cow). The producer reported that the dam of case #19 was euthanized after an injury in February 2014, nearly five years after case #19 was born. 

In this investigation, we noted that in 2009, case #17 calved on March 30, a few days after the birth of case #19 on March 25 (Figure 2). On this farm, as in most cow-calf herd practices, calving frequency was concentrated in time. The current literature5 considers horizontal transmission as a highly unlikely means of transmission of BSE and it was not further considered.
Figure 2. Timeline (birth and death) of BSE Cases #17 and #19 Born on the Same Farm
Figure 2. Timeline (birth and death) of BSE Cases #17 and #19 Born on the Same Farm. Description follows.
The image illustrates the timeline of events regarding BSE cases 17 and 19 where both animals were born on the same farm.
  • BSE case #17 was detected in February 2010.
  • The animal from case 17 was born in March 2004.
  • The birth cohort for BSE case 17 was March 2003 – March 2005.
  • The CFIA's Enhanced Feed Ban was implemented in 2007.
  • BSE case 19 was confirmed February 2015.
  • The animal from case 19 was born March 2009.
  • The birth cohort for BSE case 19 was March 2008 – March 2010.

1.4.3 Environmental Contamination on Farm (carcass disposal)


Carcass disposal could be hypothesised to contribute to environmental contamination by the BSE agent. Western Canadian cow-calf farms are typically housed on large farmlands. Alberta Agriculture and Rural Development (now Alberta Agriculture and Forestry) legislation allows natural disposal of livestock mortalities under specific conditions (the animal is disposed of on the property owned by owner of the animal; the animal was not suspected of an infectious or reportable disease, nor was it euthanized with drugs or other chemical substances; the total weight of animals disposed of in one site does not exceed 1000kg; compliance with specific distances between sites, wells, livestock facilities, residences, roads and natural parks or areas; and natural disposal does not create a nuisance)Footnote 7.

On the birth farm, dead cattle were disposed of on farm. They were transported to the disposal location, situated on the fence line of a field that is not used for grazing. BSE case #17 was, as reported, incinerated at the Lethbridge CFIA laboratory.

Cows were normally on pasture from June to December. Any animals that died during that period were left on pasture. In the Canadian cow-calf industry, the annual death loss of cows is estimated to approximately 1%Footnote 8. In a farm this size, this could represent one or two cows dead on pasture annually. If one of these were infected, for successful transmission to occur, a susceptible young animal would need to ingest the BSE agent through scavenging the carcass or ingesting contaminated soil or plants. Considering that, unlike Chronic Wasting Disease and Scrapie, there is no evidence in the scientific literature concerning potential environmental pathways for the transmission of BSE, this potential route of infection was not considered further.

1.5 Pathways for Off-farm Exposure to the BSE Agent Associated with BSE Case #19


Considering that contaminated feed was the most likely source of infectivity in this investigation, pathways of infective material entering the feed system were examined. Given the fact that the enhanced feed ban was in place over a year prior to the birth of BSE case #19, the potential pathways for feed to become contaminated with infective material are limited, given the extremely low prevalence rate of BSE and the controls surrounding SRM (see Section 1.3; Figure 1; Appendix 1). However unlikely, if the BSE agent were to enter the feed chain, the potential source of contamination could involve two pathways: (1) incomplete removal of SRM from PM, or (2) cross contamination of feed (PM or non-PM) with SRM. Investigating potential cross-contamination with PM would be of interest in mills that use both PM and non-PM material. Investigating cross-contamination of feed with SRM involves examining the sources and movement of SRM from a live infected ruminant that:

1. Dies or is killed on farm:
Carcass (which contains SRM) may be disposed of on farm (see Section  1.4.3), or may be picked up by deadstock for salvaging and rendering.

2. Dies off farm:
  1. in transport,
  2. prior to slaughter, or
  3. at an assembly area
Carcass (which contains SRM) is sent for salvage and rendering.

3. Is condemned at slaughter:
Carcass (which contains SRM) is sent for salvage and rendering.

4. Is slaughtered:
The SRM is removed, treated under a dedicated process and destroyed (or sent for destruction or disposal under license, at a remote facility). Raw inedible material from the slaughter plant is forwarded to the rendering plant.

Through any of these routes, at slaughter, salvage, rendering, or delivery of animal by-products to the mill, should controls fail, cross-contamination could occur. Therefore, the additional risks of feed being contaminated with SRM lie upstream from the feed mill, either at the rendering plant or the slaughterhouse. Many mechanisms are in place to ensure the SRM ban is effective and any potential cross contamination in the complex network of rendering, feed production, transport, storage and use are effectively eliminated (see Section  1.3; Figure 1; Appendix 1).

1.6 Pathways Investigated for BSE case #19


Epidemiological evidence across several countries suggest that a feed-borne source of BSE is the only substantiated route of infection for BSE, even after a feed ban is implemented to mitigate against the risk of feed being contaminated with the BSE agent. Many BSE affected countries that have implemented effective feed bans have detected limited numbers of cases Born After Reinforced (or enhanced or SRM) Ban. Such animals are referred to as BABs or BARBsFootnote 9. The majority are born within the first few years after the ban is introducedFootnote 10. In the UK, for example, two-thirds of BSE cases in cattle born after the original 1998 feed ban were born in the first few years after it was introducedFootnote 11.

Given the abovementioned on-farm and off-farm exposure pathways, two lines of enquiry were pursued to investigate possible sources of BSE infectivity in this case:

(1) On farm through residual or carryover of contaminated feed acquired prior to the enhanced feed ban; and

(2) Off farm through the acquisition of contaminated feed.

2. Feed Investigation


The feed investigation focused on feeds to which the case animal may have had access during its first year of life and on the manufacturing practices used to produce these feeds (March 2008 to March 2010).

2.1 Feeding Practice


A thorough and detailed feed investigation was conducted at the birth farm to identify all of the feed materials used, the suppliers and sources of these products. In addition, the feeding practices and storage and management practices were reviewed. The on-farm investigation focused on potential cross contamination incidents or incidental exposure to feeds that could have contained prohibited ruminant feed ingredients (primarily ruminant meat and bone meal) manufactured prior to July 2007.

On this farm, the calving season extended from February to June, with most calving occurring in March and April. During the first four months of life, the case animal would have nursed from its dam and had access to creep feed. In June, cow-calf pairs were moved to pastures where they were rotated through until December. All pastures were located in the same County as the birth farm, and there was no pasture sharing or mixing of animals with other farms. During this period, the case animal could have had access to hay, grain, pelleted cow ration, pelleted bull ration, free choice minerals and salt. The case animal would not have had access to milk replacer, because the only reported purchase of milk replacer was in February 2010, when the case animal was 11 months of age.

All feed products to which the BSE case was known to have had access were intended for feeding ruminants. Forages fed on the farm were grown and harvested on the farm or occasionally purchased from neighbors and transported with farm owned equipment. The producer did not mix feed on farm. Feed was purchased from the same suppliers over the years. During the period of interest, pelleted feed was delivered to the farm on a regular basis (every 3 to 9 months). The services of a feed consultant have been used since 2003. Ingredient processing of barley occurred with a portable roller; this equipment was shared with a neighboring farm. It was confirmed that this neighboring farm only used this equipment for rolling barley.

On-farm storage and usage practices of feed were such that all cattle on farm could have had access to any of the different feed types used on farm (creep, calf, cow or bull rations), all intended for feeding ruminants. Pet foods were stored in the dwelling house on site and livestock did not have access to these. Bin management and storage practices on farm could not eliminate the possibility that feed products produced prior to the enhanced feed ban may have remained (to some extent) on the farm post enhanced feed ban. However, there was no indication that feedstuff was stored for extended periods as part of the feeding practices on farm. The on-farm practices consisted of shoveling out a bin when it became empty prior to filling it again. The farmer reported this occurred approximately once a year.

Management practices on farm were similar to that of other cow-calf farms in Canada Given the nature of the feed used on farm (home grown forages, commercial feed/supplements manufactured specifically for cattle, no on farm mixing) there would have been no reason to consider the potential that feed might be contaminated. As discussed earlier, it is important to note that while the previous case (#17) born on this farm most likely became infected in 2004, it was not detected as a BSE case until February 2010, almost a year after case #19 was born and likely became infected. Considering the management practices and timelines of the two cases, it was not possible to rule out the potential for the carry-over of a small amount of residual contaminated feed on the farm.

2.2 Feed Sources


Investigations were conducted at all feed manufacturers to determine if they handled prohibited material and whether or not potential cross contamination of ruminant feed may have occurred. Specific attention was directed to ingredient sourcing, transportation, handling, manufacturing, storage and delivery/receiving practices.

Results of the investigation on the farm revealed that the case animal had potentially been exposed to various commercially prepared feeds during the period of interest (March 2008 to March 2010) (Table 1). None of the product formulations contained prohibited material.
Table 1. Commercially Prepared Feed Sources to Which the Case Animal had Potentially been Exposed
Commercial Feed Facilities (number of different feeds of interest) Facility Profile
Production Practices
Feed Type Rendering Facilities supplying ingredients
(Number and type of products) Table Note 1
Comments
A (4) Facility handled Prohibited Material (PM) for feed preparations destined to non-ruminant species.  Facility also handled non-PM rendered animal by-products. Pelleted rations J (1 PM and 1 non-PM)
K (2, non-PM)
L (1, non-PM)
M (1 PM and 1 non-PM)
N (1, non-PM)
Review of available compliance inspection records during period of interest did not identify any situations that would have resulted in the contamination of non-PM sources with PM.
B (1) Facility did not handle PM, but handled other rendered animal by-products. Mineral supplement J (1, non-PM)
L (1, non-PM)
N (1, non-PM)
USA (1, imported, non-PM)
Review of available compliance inspection records did not identify any situations that would have resulted in the contamination of mineral feeds with PM.
C (2) Facility did not handle PM, but handled other rendered animal by-products. Mineral supplement O (3, non-PM)
USA (1, imported, non-PM)
Review of available compliance inspection records did not identify any situations that would have resulted in the contamination of mineral feeds with PM.
D (1) Facility did not handle PM, but handled other rendered animal by-products. Mineral supplement L (1, non-PM)
USA (1, imported, non-PM)
Review of available compliance inspection records did not identify any situations that would have resulted in the contamination of mineral feeds with PM.
E (2)  Feed manufactured and exported to Canada from a facility in USA Lick tubs Not investigated Letter of guarantee provided by manufacturer stating that all products were free from non-prohibited ingredients in the manufacture of its products (to address BSE/restricted use of animal proteins as per US Regulations).
F (1) Feed manufactured and exported to Canada from a facility in USA Lick tubs Not investigated Letter of guarantee provided by manufacturer stating that all products were free from rendered mammalian protein (except gelatin coating on vitamins) provided by manufacturer, as well as, ingredient lists.
G (1) Facilities did not handle PM or other rendered animal by-products. Salt product Not applicable No animal by-products used in manufacture and only bulk product received is salt. Conveyances delivering salt to facility do not transport rendered products.
H (1) Facility did not handle PM or other rendered animal by-products. Salt product Not applicable
I (1) Facility did not handle PM, but did handle other rendered animal by-products. Milk replacer P (1, non-PM)
Q (1, non-PM)
R (1, non-PM)
S (1, non-PM)
T (1, non-PM)
USA (1 imported, non-PM)
Feed was received when case animal was 11 months old, so exposure to this feed ruled out as it would not have been provided in feeding practices of case animal.
Table Note
Table note 1
See Table 2 for description of rendering facilities

For each feed involved, information was gathered from facility management with regards to ingredients, the use of prohibited material in the facility, interviews with CFIA Inspectors and a review of inspection documents, as well as the compliance history of the facilities. Interviews and record reviews were also conducted to characterize transportation of incoming and finished products and to identify if these were transported by company owned or third party owned conveyances.

Based on the presence of PM and non-PM material, Facility A was considered to pose the most likely potential risk for an off-farm source of exposure to the BSE agent, if such an event had occurred. The suppliers of the mineral supplements (Facilities B, C & D) did not handle PM. The facilities did handle non-PM animal by-products, although none were included as ingredients in the mineral supplements. The potential for cross contamination with the BSE agent at Facilities B, C and D was considered negligible. Suppliers of lick tubs (Facilities E & F), located in the USA, were not investigated further. A letter from these suppliers indicated their products were free from rendered mammalian protein. Suppliers of salt products (Facilities G & H) were not considered further at risk because they do not handle PM or non-PM material. The facility supplying milk replacer (Facility I) was eliminated from further investigation with regards to the timing of purchased product and the potential for exposure of the animal. It was noted that facilities A and B were also identified as feed suppliers to the birth farm in the investigation of BSE case #17.

The supplier of the pelleted feeds (Facility A) to the birth farm produced feeds for ruminants and non-ruminant species. The non-ruminant feeds may include PM as an ingredient. Facilities that handle PM and manufacture ruminant rations are considered to be at a greater risk for potential cross contamination of feed. Facility A had documented procedures in place to prevent contamination of ruminant feeds with prohibited material in accordance with the requirements of the Feed Ban and legislative authorities. The commercial mill inspection completion rate for the area was 100% for the years 2008-2010. During the period of interest, Facility A had only one non-compliance recorded related to the feed ban (Health of Animals regulations). The non-compliance was a missing lot number on an invoice for feed containing PM and resulted in a corrective action.

A detailed review of individually manufactured feeds of interests at Facility A was conducted. It targeted 10 deliveries of the 4 different rations (creep, calf, cow or bull pellets), to which the case animal was known to be or was potentially exposed. Due to a flood at the facility, production records for 3 of these 10 feeds delivered to the farm, as well as any delivery records were not available. In reviewing the available mill records for all of the feeds delivered to the farm, there was no documentary evidence of potential cross contamination.   

2.3 Rendered Animal By-product Sources


For BSE cases born prior to the implementation of the enhanced feed ban (EFB) (July 2007), the focus of the investigations was on commercial feed mills and subsequent transportation of feed to farms, and on farm feeding practices. At that time, SRM were rendered together with other prohibited materials (PM) to produce meat and bone meal (MBM) for feeding to non-ruminant species. Consequently, the feed investigation focussed on identifying possible opportunities for cross-contamination of feeds with PM that the case animal may have been exposed to. Now that SRMs are excluded from the entire animal feed chain, for cases born after the EFB, contamination of ruminant feed with PM is no longer the most likely potential pathway of exposure to the BSE agent.

To this end, as part of the feed investigation in this case, a more detailed investigation of sources of rendered animal by-products on the premises of the commercial feed facilities during the period of interest was also undertaken. As outlined in Appendix 1, the CFIA conducts regular compliance inspections at rendering plants at frequencies based on risks of transmitting BSE down the animal feed production and supply chain. Compliance inspection records for inspections conducted at the various suppliers of rendered animal by-products identified in Table 1 were reviewed. Instances of non-compliance at these facilities were assessed in relation to the likelihood of potential transmission of the BSE agent down the supply chain to a commercial feed facility and ultimately to the birth farm. The results of this analysis are provided in Table 2. In summary, the review of available compliance inspection records did not identify any situations that would have likely resulted in the contamination of PM rendered products with SRM or non-PM rendered products with PM or SRM.

Table 2. Rendered Animal By-Products Sources to Which the Case Animal had Potentially been Exposed
Rendering Facilities Products manufactured Comments
J MBM (PM), blood meal, animal fat (tallow), animal/vegetable fat blend, SRM cracklings, feather meal Review of available compliance inspection records did not identify any situations that would have resulted in the contamination of non-PM rendered products with PM or SRM.
K Porcine MBM, poultry meal, feather meal, blood meal, animal fat, yellow grease, poultry fat, porcine fat Review of available compliance inspection records did not identify any situations that would have resulted in the contamination of non-PM rendered products with PM or SRM.
L Spray dried blood plasma Review of available compliance inspection records did not identify any situations that would have resulted in the contamination of non-PM rendered products with PM or SRM.
M MBM (PM), animal fat Review of available compliance inspection records did not identify any situations that would have resulted in the contamination of non-PM rendered products with PM or SRM.
N Fish meal, poultry meal Review of available compliance inspection records did not identify any situations that would have resulted in the contamination of non-PM rendered products with PM or SRM.
O Porcine MBM, animal/vegetable fat blend Review of available compliance inspection records did not identify any situations that would have resulted in the contamination of non-PM rendered products with PM or SRM.
P Blood plasma Review of available compliance inspection records did not identify any situations that would have resulted in the contamination of non-PM rendered products with PM or SRM.
Q Animal/vegetable fat blend Review of available compliance inspection records did not identify any situations that would have resulted in the contamination of non-PM rendered products with PM or SRM.
R Blood meal, porcine MBM Review of available compliance inspection records did not identify any situations that would have resulted in the contamination of non-PM rendered products with PM or SRM.
S Fish meal Review of available compliance inspection records did not identify any situations that would have resulted in the contamination of non-PM rendered products with PM or SRM.
T Fish meal Review of available compliance inspection records did not identify any situations that would have resulted in the contamination of non-PM rendered products with PM or SRM.

3. Identifying and Tracing Cohort Animals


Cattle identified as birth cohorts to the case animal are being traced and destroyed in accordance with OIE requirements. This aims to eliminate animals potentially exposed to the same contaminated feed as the BSE case, although it is unlikely to provide any additional protection against the backdrop of the measures already in place, which include the ongoing feed ban and the exclusion of SRM at the time of slaughter from the human food supply.

The feed and birth cohorts were, in this case, indistinguishable because all animals from the birth cohort had access to the same feed as the case animal during the first year of life. The birth cohort was determined to be animals born after March 25, 2008 and before March 25, 2010. It consisted of 746 animals, based on an exact count of births recorded during the period of interest.

The trace-out investigation targeted the 746 animals of the birth cohort. The trace out investigation located 132 live animals, 99 of which were on the birth premises. All live animals, located on 14 different premises (including the birth farm), have been placed under quarantine. Of these, 22 live cohorts have been humanely destroyed. Disposal was in accordance with OIE recommendations and the CFIA's BSE Manual of Procedures. The remaining live cohorts have been permanently identified, their movements controlled and will be destroyed, or upon their death, their carcasses disposed of in accordance with the CFIA's BSE Manual of Procedures.

Disposition of the remaining 614 cohort animals are reported by category in Table 3. To dateFootnote 12, trace out activities have been finalised for 716 animals of the 746 in the cohort. Tracing of the remaining 30 animals is expected to be completed by the end of 2015.

The OIE no longer classifies the progeny of a BSE-positive cow as equivalent risk animals. However, tracing of the calves born to the infected dam within 24 months preceding the diagnosis of BSE (2013 and 2014 calves) was undertaken to satisfy specific country export requirements. Records indicated the 2013 calf died of scours soon after birth. The 2014 calf was born at the sampling site and is currently under quarantine.
Table 3. Disposition of Animal Traces for BSE #19 Birth Cohort (n=746)
Trace Category Description Number of animals
Located The animal of interest has been located and quarantined (destroyed). 132 (22)
Confirmed dead The animal has been traced to a location where it is known to have died. 20
Confirmed slaughtered The animal has been traced to a slaughter plant, or a location known to assemble animals for slaughter only, including a terminal feedlot.  303
Exported The animal has been traced to a location where it has been reported as exported. 0
Exported and slaughtered The animal has been traced to a location where it has been reported as exported for immediate slaughter. The importing country has been notified. 118
Presumed dead The animal has been traced to a location where it is believed to have died.  The animal is not on the premises and there is no record or knowledge of it leaving the premises.  There are no further avenues of investigation to pursue.  Information on the purported disposition of the carcass is recorded if available. 3
Presumed slaughtered The animal has been traced to a location where it is believed that the animal left only to slaughter or a terminal feedlot.  There are no further avenues of investigation. 130
Untraceable All avenues of tracing have been exhausted.  The animal has not been located, or if located, has not been identified amongst non-trace animals, nor determined or believed to have died or been slaughtered. No further action is required. 10
Total closed traces Table Note 2 716
Table Note
Table Note 2
Tracing of remaining 30 animals is pending

4. Investigation Summary


Case #19 was a case of classical BSE in a Black Angus beef cow, 5 years and 10 months of age at time of diagnosis. It was born in March 2009, 20 months after the enhanced feed ban was implemented. A previous case of BSE was diagnosed on the same birth farm from an animal born in 2004.

As for other cases of classical BSE in Canada and in other countries, feed-borne infection is the most likely source of BSE in this case. BSE case #19 was born shortly after the enhanced feed ban was implemented, which may suggest residual feed contamination on-farm or off-farm as the source of infection. No significant events could be linked with this case but the potential for the carry-over of a small amount of residual contaminated feed could not be discounted. Considering the stringent safeguards implemented from 2007 to ensure that SRMs are excluded from the entire terrestrial and aquatic animal feed chains as well as fertilizer, together with the rigorous inspection oversight by the CFIA the contamination of both prohibited and non-prohibited materials with SRM at either a slaughter establishment or a rendering facility, would in all likelihood, be highly improbable. As a result, the carry-over of a small amount of residual contaminated feed associated with the earlier case (#17) on the same birth farm is the most plausible explanation for BSE case #19.

Trace-out of birth cohort animals is ongoing and expected to be completed for the end of 2015. Live cohorts traced are permanently identified, their movements controlled and upon death or destruction are disposed of in accordance with OIE requirements and the CFIA's BSE Manual of Procedures.

5. Impact of Current Findings


The results of Canada's ongoing surveillance program continue to confirm that BSE remains under effective control. Since it is widely recognised that cattle are most susceptible to becoming infected in their first year of life, an analysis of surveillance test results stratified by the year of birth (a birth cohort analysis) provides a surrogate measure of exposure to the BSE-agent in the cattle population in any given year. Even though Canada has recently had a BSE case born almost two years after enhancements were made to the feed ban in 2007 to exclude SRM from the entire terrestrial and aquatic animal feed chains, the updated results from a birth cohort analysis incorporating this case confirm that the overall risk profile has not changedFootnote 13. The impact of this case on the prevalence estimates for the 2009 and subsequent birth cohorts is inconsequential. They remain extremely low.

Appendix 1. Enhanced Feed Ban Compliance Inspection Programs


Abattoir:

In federally registered abattoirs inspections are undertaken on a daily basis by an on-site CFIA inspector. This includes segregation in the inedible area, staining, the dedication and labelling of containers and the verification that transporters picking up the SRM have a valid and current CFIA permit authorizing this activity. For non-federally registered abattoirs, inspections are carried out by on-site provincial inspectors, or quarterly by CFIA or provincial inspectors.

Transporters of SRM:

Transportation of SRM, including bovine deadstock from which SRM has not been removed, and SRM that has been subjected to intermediate processing (such as rendering or composting), is controlled through the issuance of permits from the CFIA. Permits are issued annually for commercial operations and permitted site is subject to quarterly inspections.

Rendering facilities:

During the period of interest (2008-2010), the inspection frequency of inedible rendering plants in Canada by CFIA was as follows:
Table 1.1 – Inspection Frequency for Inedible Rendering Plants
Facility Risk Profile 2008-09 2009-10
Process SRM, PM and/or non-PM Full time
(24 hour daily presence)
Full time Table Note 3
(24 hour daily presence)
Process SRM only (stand-alone facility) 4 inspections/ year 4 inspections/ year
Process PM and non-PM 4 inspections/ year 4 inspections/ year
Process PM only 2 inspections/ year 2 inspections/ year
Process non-PM only 2 inspections/ year 1 inspection/ year
Table Note
Table Note 3
During 2009-10. Inspection frequency at these facilities, based on an excellent level of ongoing compliance, transitioned to 4 inspections/ year

All inedible rendering plants operating in Canada require a permit to operate, which is issued on an annual basis by the CFIA. Prior to the issuance of a permit to operate, each rendering plant must be fully inspected to confirm that they are operating in accordance with the conditions of their permit, including compliance with the Health of Animals Regulations and Feeds Regulations. Inspections verify that written procedures and records of the facility meet the regulatory requirements related to preventing cross-contamination of non-prohibited materials with PM or SRM during the transportation and handling (e.g. delivery vehicles, containers, tools and other equipment used to collect, remove and transport) of raw material or finished rendered product. If non-compliance is identified, mechanisms are in place to control and mitigate risks in terms of product control and systemic corrections by the facility.

Confinement and Destruction of SRM:

A CFIA permit is required for the confinement and destruction of deadstock cattle containing SRM; meat and bone meal (MBM) made from deadstock cattle or SRM; and compost made from deadstock cattle or SRM and permitted site is subject to quarterly inspections.

Commercial Feed Mills:

Commercial Feed Mill inspections are conducted at commercial feed manufacturing establishments to:

  • confirm that feeds are being manufactured and used in compliance with the Feeds Regulations and Health of Animal Regulations, for the purpose of reducing the potential for feed-related problems affecting animal and/or human health or the environment; and
  • confirm that feeds are being imported and sold in compliance with the Feeds Act and Regulations and the Health of Animal Act and Regulations.

The purpose of this program is to verify that commercial feed mills:

  • manufacture safe, compliant, correctly labelled feed; and
  • follow procedures relating to feed manufacturing, labelling and record keeping, to ensure that the integrity of the feed is maintained and the complete distribution of any feed is identified.

The risk categorization for commercial feed mills considers the food safety and animal health risks associated with the spread of Transmissible Spongiform Encephalopathies (TSEs) via feeds and the use of medications in feeds.

The following risk categories have been identified for commercial feed mills:

  • High Risk –TSE
    • Facilities that manufacture feeds containing prohibited material and manufacture ruminant feeds
  • Low Risk-TSE
    • Facilities that do not have both risk factors for TSE
  • High Risk – Medications
  • Low Risk - Medications

These risk factors are used to determine inspection task frequencies for feed manufacturing facilities. The table below identifies the risk factors and the corresponding number of inspection tasks to be assessed at commercial feed mills based on the risk categories.

During the period of interest (2008-2010), the inspection frequency of commercial feed mills was as follows:

Table 1.2 – Inspection Frequency for Commercial Feed Mills
Risk Category Risk Factors 2008-09 2009-10
1 High Risk TSE and High Risk Medications 4 inspections/ year 3 inspections/ year
2 High Risk TSE and Low Risk Medications 2 inspections/ year 2 inspections/ year
3 Low Risk TSE and High Risk Medications 2 inspections/ year 2 inspections/ year
4 Low Risk TSE and Low Risk Medications 1 inspection/ year 1 inspection/ year