A study on Maedi-Visna and Caprine Arthritis Encephalitis in Malta

Abstract

The rearing of sheep and goats has long been an integral part of the Maltese fanning activity. Maedi-Visna and Caprine Arthritis Encephalitis are relatively common chronic infections of sheep and goats resulting in economic loss to the sheep and goat industry. The objective of this study was to determine if there is a high or low prevalence of the diseases in flocks in the Maltese Islands. The study is divided into two parts: one is experimental and treats the presence of the Maedi-Visna and Caprine Arthritis Encephalitis in sheep and goats in several farms in Malta and Gozo and the other is based on a series of interviews to farmers concerning knowledge of these diseases. Between January and August of 2011, 424 blood samples from goats and 504 blood samples of sheep were collected from 292 farms. In August 2011 there were 12,174 sheep and 4,837 goats present in Malta and Gozo which is a total of 17,011 heads. This means that more that 5% of the whole population of sheep and goats were sampled. Testing for Maedi-Visna and Caprine Arthritis Encephalitis was carried out by ELISA method. Since the incubation period of the diseases is usually between two to four years, the majority of sampled sheep and goats were older than four years. 26% of sampled sheep and 25% of sampled goats were tested positive to the disease. This indicates that there is a high percentage of sero-positive sheep and goats in Malta and Gozo. Results also suggest that the diseases are widespread across the Islands. A number of farmers were interviewed to determine their knowledge on livestock diseases and on Maedi-Visna and Caprine Arthritis Encephalitis. This was done after the results were calculated. With this regard, an information booklet on these diseases was also set-up with the scope of helping farmers to understand such diseases and avoid further spreading of the virus.