Immune responses in goats to caprine arthritis-encephalitis virus

Evaluation of caprine arthritis-encephalitis virus transmission in newborn goat kids

ABSTRACT: Caprine arthritis encephalitis causes considerable losses in goat production. The main form of the caprine arthritis encephalitis virus transmission is through the ingestion of colostrum or milk from infected females. However, some transmissions cannot be explained in this manner. Therefore, this study aimed to evaluate transplacental transmission of caprine arthritis encephalitis virus. Blood samples were collected from 283 newborn kids of Anglo-Nubian and Saanen breeds born from seropositive and seronegative goats. Samples were collected immediately after birth and analyzed with agarose gel immunodiffusion and western blot. All samples were negative in the agarose gel immunodiffusion. However, the western blot test demonstrated that four kids were born positive for caprine arthritis encephalitis virus. This result indicates that although in a low frequency (1.4%), there is a possibility of transplacental transmission of small ruminant lentivirus.

Diagnostic tests for small ruminant lentiviruses

Maedi visna virus and caprine arthritis encephalitis virus are closely related retroviruses that cause chronic inflammatory disease in small ruminants. The infections are characterised by insidious onset and slow progression. Diagnosis of infection is usually by serological testing. A variety of assays are available for this purpose, though the relative sensitivity and specificity of these assays has not been compared systematically. Here we review recent developments in laboratory diagnostic methods and their use in field diagnosis. The results suggest that a combination of ELISA and PCR might afford optimal detection of SRLV infection.