PRELIMINARY SEROMONITORING OF RINDERPEST AMONG CATTLE RAISED UNDER DIFFERENT HUSBANDRY SYSTEMS IN SAUDI-ARABIA

Using the competitive enzyme-linked immunosorbent assay for the seromo nitoring of rinderpest in Saudi Arabia, antibodies were detected in 30 % of the sera of 1,018 cattle slaughtered at Riyadh abattoir during Ju ne and July 1995. The correlation between the detection of antibodies and the origins of the slaughtered animals was analysed. All the culle d dairy cows had detectable antibodies. The proportions of bulls givin g serologically positive results were as follows: 57% for animals impo rted from rinderpest-free countries and vaccinated upon arrival in Sau di quarantine, 20% for native breeding animals and 17% for five-to ten -month-old bull calves born on commercial dairy farms and then raised on separate feedlot farms. In addition, of 105 native cattle sacrifice d during the Hajj season in May 1994, 77% had antibodies against rinde rpest virus. On the other hand, testing of 17 groups of dairy heifers (from 1 week to 24 months of age), born to immune dams and vaccinated against rinderpest at the ages of six and ten months, revealed the abs ence of detectable antibodies in the sera of some animals which were b etween two and ten months of age. Results are interpreted in relation to evaluation of the continuing vaccination programmes and their effic acy as an element of the national programme for the control of rinderp est.