Seroepidemiology of Brucellosis on Dairy Cattle in Small-Holders Farms, in West Java

Abstract

Brucellosis in cattle causing abortion and infertility in adult animals and the main causative agent is Brucella abortus. The objective of the study was to determine the seroprevalence and several putative factors in the occurrence of brucellosis among herds of dairy cattle in small holder farms. The study was carried out in the districts with high risk of brucellosis in dairy cattle production centers in Bandung regency, West Java Province. The sampling strategy in this study was risk-based surveillance. A total of 260 blood samples were collected from cows owned by farmers who have had a history of cow abortion and were suspected of having a risk of brucellosis. Serological examination of bovine serum with RBT and CFT tests were performed. True infection reactions cannot be distinguished from serological reactions caused by the Brucella abortus vaccine strain S19. Currently, B. abortus vaccine strain RB51 is being applied in Java islands for preventing of brucellosis in dairy cattle. Thus, the positive result of serological reaction test shows brucellosis reactor. The overall seroprevalence of brucellosis was found to be 15.77%. The finding of this study suggested that more than 50% abortion occurred at gestational age more than 5 months. The result indicated that there was a relationship between brucellosis seropositive and the incidence of abortion, in which the risk of brucellosis was 3.35 times more in cows that had experienced abortion than in cows that has not experienced abortion. Vaccination coverage was relatively low (44.11%), and prevented 3.1% of dairy cows against brucellosis. This study is essential for disease control and prevention measures. Further studies need to be carried out on the factors that influence the low efficacy of the RB51 vaccine in dairy cows.