BackgroundThree distinct forms of bovine spongiform encephalopathy (BSE), defined as classical (C-), low (L-) or high (H-) type, have been detected through ongoing active and passive surveillance systems for the disease.The aim of the present study was to compare the ability of two sets of immunohistochemical (IHC) and Western blot (WB) BSE confirmatory protocols to detect C- and atypical (L- and H-type) BSE forms.Obex samples from cases of United States and Italian C-type BSE, a U.S. H-type and an Italian L-type BSE case were tested in parallel using the two IHC sets and WB methods.ResultsThe two IHC techniques proved equivalent in identifying and differentiating between C-type, L-type and H-type BSE. The IHC protocols appeared consistent in the identification of PrPSc distribution and deposition patterns in relation to the BSE type examined. Both IHC methods evidenced three distinct PrPSc phenotypes for each type of BSE: prevailing granular and linear tracts pattern in the C-type; intraglial and intraneuronal deposits in the H-type; plaques in the L-type.Also, the two techniques gave comparable results for PrPSc staining intensity on the C- and L-type BSE samples, whereas a higher amount of intraglial and intraneuronal PrPSc deposition on the H-type BSE case was revealed by the method based on a stronger demasking step.Both WB methods were consistent in identifying classical and atypical BSE forms and in differentiating the specific PrPSc molecular weight and glycoform ratios of each form.ConclusionsThe study showed that the IHC and WB BSE confirmatory methods were equally able to recognize C-, L- and H-type BSE forms and to discriminate between their different immunohistochemical and molecular phenotypes. Of note is that for the first time one of the two sets of BSE confirmatory protocols proved effective in identifying the L-type BSE form. This finding helps to validate the suitability of the BSE confirmatory tests for BSE surveillance currently in place.

Abstract. Feline spongiform encephalopathy (FSE) is a transmissible spongiform encephalopathy associated with the consumption of feedstuffs contaminated with tissue from bovine spongiform encephalopathy-affected cattle and characterized by the accumulation in the central nervous system of an abnormal isoform of the prion protein (PrP sc ). Clinically, it presents as a progressive fatal neurologic syndrome that is not easily distinguished from other feline neurologic conditions. Most cases of FSE have been reported in England, where it was first detected in 1990, but a few cases have been reported from other European countries. To identify possible cases of FSE in Italy, the Italian Ministry of Health funded a 2-year surveillance project during which the brains from 110 domestic cats with neurologic signs were evaluated histologically for spongiform encephalopathy and immunohistochemically to detect PrP sc . Although no cases of FSE were found, the study proved useful in monitoring the Italian cat population for other neurologic diseases: neoplasia (21.8%), toxic-metabolic encephalopathy (18.2%), granulomatous encephalitis (15.5%), suppurative encephalitis (4.6%), trauma (3.6%), circulatory disorders (3.6%), degeneration (2.7%), nonsuppurative encephalitis (2.7%), and neuromuscular diseases (1.8%). No histologic lesions were found in 20% of the brains, and samples from 5.5% of the cats were rejected as unsuitable.

The 'Transmissible Spongiform Encephalopathy (TSE) Roadmap' was published by the European Commission on 15 July 2005. The TSE Roadmap proposes the relaxation of bovine spongiform encephalopathy (BSE) measures in the short, medium and long term. According to the Roadmap, any relaxation of BSE measures following the scientific assessment should be initiated by an open discussion with all stakeholders and supported by a strong communication strategy. This paper discusses the risk perception, risk communication and risk management of TSEs in Europe, exemplified by the TSE Roadmap. The main conclusion is that in general, BSE is no longer a 'hot' topic for stakeholders, but there are slight differences between countries with respect to specific measures. Another important conclusion is that the TSE Roadmap is a very effective tool for risk communication with stakeholders.

Species substitution is a common commercial fraud, mainly applied to fish species. It is thus important to have analytical methods for species identification. DNA analysis can be a suitable technique: some mitochondrial genes are actually recognized as valuable markers for species discrimination. Aim of this work was thus to evaluate the capability of cytb and COI genes to discriminate the species of fish (n=89) which are commonly substituted. In the last four years of activity on field, the laboratory analysed, using the FINS method (Forensically Informative Nucleotide Sequencing), 146 samples, belonging to several fish species, sent by veterinary officers in the frame of their activities of control: in this work, results about number and kind of fraud are reported. Additionally, samples directly purchased by the lab were examined. The obtained results showed that the genetic markers have a high discriminatory power and that the method is highly suitable. The frequent detection of species substitution in the samples collected on field showed the importance of controlling this kind of frauds in the fish market

Abstract:The Bovine Spongiform Encephalopathy (BSE)