Contribution of meat inspection to animal health surveillance in Sheep and Goats
The present document has been produced and adopted by the bodies identified above as authors. This task has been carried out exclusively by the authors in the context of a contract between the European Food Safety Authority and the authors, awarded following a tender procedure. The present document is published complying with the transparency principle to which the Authority is subject. It may not be considered as an output adopted by the Authority. The European Food Safety Authority reserves its rights, view and position as regards the issues addressed and the conclusions reached in the present document, without prejudice to the rights of the authors.
The objective of this work was to assist a working group (WG) appointed by the Animal Health and Animal Welfare Panel (AHAW) in the development of generic stochastic and deterministic models of the meat inspection system to investigate the probability of detection of twenty specific diseases and welfare conditions within that system and to compare the effectiveness of abattoir and clinical surveillance. The impact of three post mortem inspection scenarios (current, intermediate and visual only inspection) was investigated. Definitions of mild and typical cases were defined from the literature and clarified through elicitation with three small ruminant experts. The parameter values for models were derived from the literature and from expert elicitation. The probability of detection was assessed for the ante and post mortem components of abattoir inspection for detectable (mild and typical cases) and all (mild, typical and non-detectable) cases and used as inputs to evaluate the effectiveness of slaughterhouse inspections as a surveillance system component. This was established by using two types of scenario tree models: the component sensitivity model (used for exotic diseases) and detection fraction model (used for endemic diseases/welfare conditions). With the visual only inspection of detectable cases, there was a significant drop in detection probability of detectable cases of liver fluke and bovine tuberculosis (bTB) in goats. When all cases were taken into consideration there was no significant reduction in the detection of any diseases or welfare conditions. Surveillance using clinical observations from the field (clinical surveillance) was more effective than surveillance using observations from abattoirs (abattoir surveillance) at detecting FMD and the combined abattoir and clinical surveillance of sheep scab. Abattoir surveillance combined with clinical surveillance was more effective than either surveillance component on its own for detection of liver fluke, lower respiratory infections, and leg and foot disorders.