Development Of a Rapid On-Site Diagnostic Test to Detect Small Ruminant Lentivirus Antibody In Goat and Sheep Milk

Small ruminant lentiviruses (SRLV) cause persistent infection and chronic diseases in sheep and goats that can reduce animal fitness, reproduction, and milk production/quality. A reduction in milk will lead to economic losses for dairies, which is accompanied by a reduction in nutrition for kids and lambs that decreases meat and fiber production. A reduction in reproductive efficiency can lower the rate of herd/flock growth or replacement and is particularly damaging in populations with a high incidence of SRLV infection. SRLV also impact the meat industry in the U.S. and, globally, goats and sheep are significant and important sources of protein that are put at risk. There is no treatment or vaccine for SRLV so animals are culled or segregated based on costly clinical and in vitro diagnostic results. Additionally, farm veterinary usage is low, resulting in reduced disease surveillance.Most SRLV infections are transferred from the mother to the offspring during the ingestion of virus-containing colostrum and milk. Veterinary Diagnostic Technology, Inc., proposes developing a quick, on-site test for SRLVfor use by the farmer in the form of a lateral flow assay (LFA). LFA, most often associated with home pregnancy tests, are powerful tools being used in environmental testing and human and animal diagnostics. To develop this test, we will construct artificial proteins that mimic the viral proteins best recognized by sheep and goat antibodies. Through careful design and selection, we aim to produce proteins that can be used for both sheep and goat samples and that can detect small amounts of antibodies present in the milk that are reactive against virus. By sampling the milk with an LFA at the time of birth the farmer can make real-time decisions to mitigate transmission to the newborn, improving SRLV control in their animals.If SRLV infection of sheep and goats can be reduced by the identification of infected does and ewes, then there can be an expected increase in the yields of milk and meat, thus improving the reliability of nutritious food sources. This can then increase sustainable land use by reducing the areas needed for goats and sheep and reducing the amount of feed needed for equivalent amounts of meat and milk. Ultimately, we hope to deliver a tool to the producer for the direct management of these diseases of sheep and goats and thereby minimize economic losses and improve food safety and security.