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Due to the widely supported theory of bovine spongiform encephalopathy (BSE) spread in cattle by contaminated animal feeds, screening of feed products has become essential. For many years, manufacturers have used blood and plasma proteins as high quality ingredients of foods for both pets and farm animals. However, in Europe, the Commission Regulation 1234/2003/EC temporally bans the use of processed animal proteins, including blood-derivative products, in feedstuffs for all farm animals which are fattened or bred for the production of food. This regulation has some exceptions, such as the use of non ruminant blood products into the feed of farm fish. Authorization of the re-introduction of these proteins into animal feed formulations, especially non ruminant proteins into the feed for non ruminant farm animals, is expected when adequate control methods to discriminate ruminant proteins exist. Currently, the number of validated methods to differentiate the species of origin for most of the animal by-products is limited. Here we report the development of a rapid and sensitive polymerase chain reaction (PCR)-based assay, which allows detection of bovine or porcine specific mitochondrial DNAfrom spray-dried blood derivate products (plasma, whole blood and red cells), as a marker for bovine contamination in porcine products. Sample extracts, suitable for PCR, were easily and quickly obtained with the commercial PrepManTM Ultra reagent (Applied Biosystems). To confirm the porcine origin of the samples, primers targeting a specific region of 134 bp of the porcine cytochrome b coding sequence were designed (cytbporc1-F and cytbporc2-R). Previously published PCR primers (L8129 and H8357), specific for a 271 bp fragment of the bovine mitochondrial ATPase 8-ATPase 6 genes, were chosen to accomplish amplification of bovine DNA. The limit of detection (LOD) of the bovine PCR assay was at least of 0.05% (v/v) of bovine inclusion in spray-dried porcine plasma or red cells fraction. In dried whole blood samples, sensitivity of the method was found to be at least of 0.1 % (v/v). Since the method described here exhibits high specificity and sensitivity and it is rapid, simple and consistent, it could be successfully utilized as a routine control assay to evaluate the presence of bovine materials in spray-dried blood products.

Copyright of Revue d'Etudes en Agriculture et Environnement is the property of Institut National de la Recherche Agronomique (INRA) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revue d'Etudes en Agriculture et Environnement is the property of Institut National de la Recherche Agronomique (INRA) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article presents information about a conflict arising in the French Food Safety Agency (Agence Française de Sécurité Sanitaire des Aliments; AFSSA) in 2004, involving the animal and human disease Query Fever. The article notes that the conflict occurring among members of the AFSSA reveals the agency's hierarchical organization. Further comments are given concerning the impact of mad cow disease on governmental responses to zoonoses, which are communicable diseases carried by animals.

Based on a sociological survey about the management of risks due to the possible transmission of Bovine Spongiform Encephalopathy to sheep cattle, this article highlights that the development of public health action doesn't stem from a new prevailing norm of precaution, but from co-production processes where the visibility of hypothesis concerning risks is now at stake. We show that the prescription of precaution formulated by the new « Agence française de sécurité sanitaire et alimentaire » is grasped and worked out by the sheep breeding actors. We analyse the mutual learning processes and innovation mechanisms which shape a regime of risk management characterized by a "discrete precaution". [ABSTRACT FROM AUTHOR]

Abstract: In 1999, three rapid tests (Prionics, Bio-Rad, Enfer) have been validated by the European Commission for the post-mortem diagnosis of BSE in cattle. They are now used on a large scale over the entire Europe. In absence of antibodies specifically recognizing the native conformation PrPres, its selective determination is based on the biochemical properties of this abnormal form (PK resistance, aggregation in presence of detergents). In addition, all these tests include a denaturation step so that PrP can be detected by appropriate antibodies. When applied on “risk populations” or on “healthy animals” entering into the human food chain, these rapid tests have provided a better estimation of the epizootic and allowed an efficient removal of animals bearing a risk for human consumption. Since 2002, they have also been used for the post-mortem diagnosis of scrapie in sheep and goat. Five new tests have been recently evaluated (ID-Lelystad; Perkin-elmer, Prionics Check LIA, UCSF, Imperial college) but it is too early to know which place they will take in the field. Current tests allow a preclinical diagnosis of TSE, especially in sheep and goats for which a very early detection is possible in peripheral lymphoid tissues. However, to date, no test on living animal has been validated. Taking into account the important number of research teams now involved on this topic one may expect spectacular progress in the forthcoming years. [Copyright &y& Elsevier]

In 2003, Prions still constitute a biological enigma and a public health concern. The risks of transmission of the so called “mad cow disease” are now under control but concerns still persist about potential secondary transmissions, notably via blood transfusion. Information obtained from diseases previously observed in animals (scrapie of sheep and goat) and in man (Kuru, Creutzfeldt-Jakob disease) demonstrate the complexity of the relations between these transmissible agents and their host. The difficulty in decontamination, the very long silent incubation period during which diagnosis is not possible and the lack of treatment are alarming elements which explain the increased perception of risk for these diseases. The development of rapid screening tests used on bovine at slaughterhouse has represented an important improvement in the development of a targeted protection against these agents. Today, technical evolutions in diagnosis let us imagine the possibility of blood detection for prions: on one hand new garanties for security may arise but on the other hand it points out the potential infectivity of blood with these agents responsible for constant fatal diseases. Precautionary security measures have to ensure an optimal ratio benefit/risk for the patient and thus, in this field, to balance the risk linked to prions with those clearly identified elsewhere. [Copyright &y& Elsevier]

Copyright of Swiss Journal of Sociology / Schweizerische Zeitschrift für Soziologie is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The collective risk situations put the settings of expertise to the test. In this paper, we study the activity of the french interministerial committee called for answering the problems caused by the bovine spongiform encephalopathy. The analyse of the activity of expertise is focused on the rules and the procedures mobilized by the experts to produce their advices, without separating their production from the framewok of justification of the governmental action. We show how this committee formed a collective producer of documents in order to leave traces of the way he carries out his mission, and particularly his relationships with his administrative supervision through a game of written questions and answers. [Copyright &y& Elsevier]

The concept of "one health" applies perfectly to human health and animal health because many diseases are zoonoses. There are many historical examples of effective collaboration between veterinary medicine and human medicine in the development of the first vaccines used in the world (smallpox, rabies, tetanus, diphtheria, tuberculosis, etc.). But when a new disease appears in animals, the risk of possible transmission to humans is difficult to estimate. In the latter case, the loss of consumer confidence in the face of scientific uncertainties can cause a health crisis (examples of bovine spongiform encephalopathy and H5N1 avian plague). But the most serious crisis that we have known since early 2020 is Covid-19 pandemic, which confirms that the modification of the ecosystems of certain wild species such as the horseshoe bats can have significant consequences for the public health. Animals infected with Covid-19 have been contaminated by humans but we cannot currently exclude an animal reservoir risk for SARS-CoV-2 which has circulated around the world.

Abstract: Variant Creutzfeldt-Jakob disease (vCJD) is the only form of prion diseases linked to bovine spongiform encephalopathy (BSE). The surgical and anaesthetic management in patients having Creutzfeldt-Jakob disease is rare. Maternofoetal and human transmission of Creutzfeldt-Jakob disease is still unknown. The principles for managing these new risks are not described in obstetric recommendations. We report the case of an 18-year-old woman, who developed the variant Creutzfeldt-Jakob disease during her pregnancy. [ABSTRACT FROM AUTHOR]

Abstract: Variant Creutzfeldt-Jakob disease (vCJD) is the only form of prion diseases linked to bovine spongiform encephalopathy (BSE). The disease was first described in the United-Kingdom (UK) and France is the second affected country with 21 cases. Clinical, genetic and neuropathological features are the same in both countries. Comparison of the total number of cases in France and in the UK, according to dates of onset, shows that, in France, the maximum incidence seems to be five years delayed and that, in the UK, the number of vCJD cases regularly decreases since 1999. Delayed exposure to contaminated beef products in France compared to the UK could explain this temporal gap. Three cases of vCJD after transfusion of labile blood products were observed in the UK. No such of cases were observed in France but three patients developing signs of vCJD in 2004 were blood donors. A total of 42 recipients were identified with 17 recipients still alive. [Copyright &y& Elsevier]