NR ATKY
AU Bozzetta,E.; Nappi,R.; Maurella,C.; Ru,G.; Corgiat Loja,G.; Negro,M.; Zolli,R.; Gai,F.; Caramelli,M.
TI Evaluation of the Ridascreen risk material 10/5 enzyme immunoassay for the detection of central nervous tissue at slaughterhouse
QU International Conference - Prion 2005: Between fundamentals and society's needs - 19.10.-21.10.2005, Congress Center Düsseldorf - Poster Session: Diagnosis DIA-36
PT Konferenz-Poster
AB
Since 1st October 2003 according to Reg.(CE) 1139/2003, a sampling plan using an appropriate laboratory test to detect Central Nervous System (CNS) tissue in bovine head meat has to be in place in each Member State, in order to protect public health from BSE risk.
We evaluated the accuracy and reliability of Ridascreen Risk Material 10/5, an enzyme immunoassay for targeting a CNS-specific marker protein, the glial fibrillary acidic protein. 503 true negative samples were obtained by aliquoting the homogenized meat from the hind leg of two fallen stock bovines (least likely to be contaminated by CNS tissue).568 true positive samples were prepared by mixing bovine brain to get specimens with three increasing concentration (0.1%; 0.2%; 0.4%) in bovine muscle tissue. A ROC curve has been plotted in order to identify the best cut-off in term of CNS concentration. In this case the cut-off guarantees the highest level for both sensitivity and specificity. Reliability was calculated by mean of Cohen's Kappa.
The obtained results show high values for both sensitivity and specificity: i.e. 97.9% and 97.4% respectively. The optimal value in which the results of the tests are best classified corresponded to a level of concentration of 0.049%. Moreover the results of the study of reliability show a very good precision of the test. To assess the inter-rater reliability data coming from two diagnostic sessions have been analysed; in the first day the K was 1 (IC95% 1.00-1.00), whereas in the second day, K was 0.78 (IC95% 0.38-1.00). With regard to intra-rater reliability, the K obtained were 0.78 (IC95% 0.38-1.00) and 1 (IC95% 1.00-1.00) respectively. As the results show that Ridascreen Risk Material 10/5 could be a valid tool for meat monitoring with regard to CNS tissue contamination, the authors will suggest a national application for this diagnostic procedure.
This work was funded by Piedmont Region (Ricerca Sanitaria Finalizzata R3C/2003) and by the Italian Health Ministry.
AD E.Bozzetta, R.Nappi, C.Maurella, G.Ru, R.Zolli, F.Gai, M.Caramelli, CEA, IZSPLVA, Italy; G.Corgiat Loja, Regional Veterinary Services, Piedmont Region; M.Negro, ASL 16, Veterinary Services, Italy
SP englisch
PO Deutschland