Detection of immunological tolerance to bovine spumavirus (BSV) with evidence for salivary excretion and spread of BSV from the tolerant animal.
A group of 17 Friesian-Holstein steers held in individual pens was examined for evidence of infection with bovine spumavirus (BSV). Serum was examined for specific antibody by 2 serological procedures, and circulatory leucocytes and throat swabs were examined for the presence of circulatory leucocyte-associated BSV (CLAB) and saliva-associated BSV (SAB). Initial tests showed that 7 of the 17 steers had specific antibody to BSV by both serological procedures, and a further steer developed such antibody during the first 3 months of holding the animals in single contiguous pens. All 8 of these specific antibody-positive steers were CLAB positive and SAB negative. Nine steers showed no specific antibody to BSV by either of the 2 serological procedures; 8 of these 9 steers showed no evidence of CLAB or SAB. The exception was one steer which was CLAB- and SAB-positive at each of 30 samplings taken over a period of 9 months observation, whilst remaining specific-antibody free. This steer was classed as immunologically tolerant of BSV, and epidemiological data suggested that lateral spread of infection had originated from this animal through the agency of saliva.
Kertayadnya
I G
IG
Graduate School of Tropical Veterinary Science, James Cook University, Townsville, Qld., Australia.
Johnson
R H
RH
Abher
I
I
Burgess
G W
GW
D000818:Animals; D000914:Antibodies, Viral / Q000032:analysis; D002417:Cattle; D002418:Cattle Diseases / Q000276:immunology* / Q000635:transmission; D007108:Immune Tolerance; D008297:Male; D012190:Retroviridae / Q000276:immunology*; D012192:Retroviridae Infections / Q000276:immunology / Q000635:transmission / Q000662:veterinary*; D012463:Saliva / Q000276:immunology / Q000382:microbiology; D016092:Spumavirus / Q000276:immunology* / Q000302:isolation & purification / Q000472:pathogenicity
D000914:Antibodies, Viral