[Proposal of the DVG Specialist Group "Diseases of Small Ruminants and New World Camelids" for a program to combat Maedi-Visna infection in sheep herds and caprine arthritis-encephalitis infection in goat herds].

Abstract

Abstract: The control of small ruminant lentivirus (SRLV) infections - Maedi, Visna, and caprine arthritis and encephalitis (CAE) - is based on the establishment of SRLV-free closed herds, achieved by serologically testing of all small ruminants aged one year and older for antibodies against SRLV. After four completely negative serological test results within a period of at least 24 months, a farm is recognized as SRLV-free. Maintaining SRLV-free status is based on regular serological testing of all small ruminants in the herd over one year of age. To reduce the administrative and financial burden involved in maintaining this status, various breeding associations have introduced significant simplifications and relaxations, some of which differ to such an extent that the intensity of surveillance varies considerably. Against this background, the members of the Specialist Group for Small Ruminants and New World Camelids of the German Veterinary Medical Society have drawn up this proposal to standard the guidelines for the control and monitoring of SRLV. The proposal must now be adopted and ratified by the relevant breeding associations.

Abstract: Even under the proposed new guidelines, no fundamental changes to the requirements for initial recognition as an SRLV-free herd have been made. However, to maintain this status, follow-up testing may now be reduced to every two years once the herd has been SRLV free for three years. After at least five years with free status, the herd may be tested annually either via a random sample (detection of a 1% prevalence with 95% certainty), or samples from all adult animals in the herd may be tested in pools of five using an ELISA approved for this purpose.