Chronic disease in goats orally infected with two isolates of the caprine arthritis-encephalitis lentivirus.
Newborn Saanen goats were orally infected with two distinct biologically cloned isolates of the caprine arthritis-encephalitis lentivirus (CAEV), designated CAEV(63) (Crawford TB, Adams DS, Cheevers WP, Cork LC: Science 207:997, 1980) and CAEV (Co) (Cork LC, Hadlow WJ, Crawford TB, Gorham JR, Piper RC: J Infect Dis 129:134, 1974; Narayan O, Clements JE, Strandberg JD, Cork LC, Griffin DE: J Gen Virol 50:69, 1980). All infected goats seroconverted for antibodies to CAEV, and there were no serologic reversions. Histologic lesions consisted of chronic inflammation of variable incidence and severity in joints and mammary gland. Clinical arthritis, estimated by enlargement of carpi, correlated with severe inflammation of radiocarpal synovium. Statistical evaluations of clinical and histologic parameters indicated that chronic joint disease was significantly more frequent and more severe in the group of goats infected with CAEV(63) than in the group infected with CAEV (Co). Thus, the severity of chronic arthritis is determined in part by the relative pathogenicity of individual CAEV isolates. Analysis of the temporal development of carpal arthritis during the first 3 years of infection indicated that (a) the extent of eventual chronic disease in individual joints was apparent relatively early after infection, (b) joints with severe chronic lesions were clinically enlarged at irregular intervals and (c) the pattern of recurrent arthritis was unique for each joint. Thus, chronic arthritis develops with a progressive course which may be promoted by recrudescent inflammation. Infectious virus was recovered 3 years after infection from selected tissues of 12 of 17 CAEV(63)-infected goats and 11 of 18 CAEV(Co)-infected goats. Virus recovery was independent of the virus isolate used for experimental infection and did not correlate with the severity of lesions.
Cheevers
W P
WP
Department of Veterinary Microbiology and Pathology, Washington State University, Pullman.
Knowles
D P
DP
McGuire
T C
TC
Cunningham
D R
DR
Adams
D S
DS
Gorham
J R
JR
D000284:Administration, Oral; D000818:Animals; D001170:Arthritis, Infectious / Q000382:microbiology / Q000473:pathology / Q000662:veterinary*; D002908:Chronic Disease; D004660:Encephalitis / Q000382:microbiology / Q000662:veterinary; D005260:Female; D006041:Goats / Q000382:microbiology*; D008413:Mastitis / Q000382:microbiology / Q000473:pathology / Q000662:veterinary; D012192:Retroviridae Infections / Q000473:pathology / Q000662:veterinary*; D014790:Visna-maedi virus