Transmission of caprine arthritis encephalitis virus between sheep

• Published in: Ciência rural 2018-01, Vol.48 (10)
• Main Authors: Lima, Carla Caroline Valença de, Ayres, Maria Consuêlo Caribé, Pinheiro, Raymundo Rizaldo, Costa, Joselito Nunes, Souza, Thiago Sampaio de, Pinheiro, Alice Andrioli, Azevedo, Dalva Alana Aragão, Santos, Vanderlan Warlington Souza dos
• Format: Article
• Language: eng ; por
• Subjects: AGRONOMY; Animals; Anticoagulants; Antigens; Arthritis; CAEV; Deoxyribonucleic acid; DNA; Encephalitis; Enzyme immunoassay; Enzyme-linked immunosorbent assay; Exposure; Food contamination & poisoning; Immunoassay; Immunoblotting; Immunodiffusion; Infections; intra-species transmission; lentiviruses; Milk; Mothers; MVV; Polymerase chain reaction; Seroconversion; Serology; Sheep; SRLV; Viruses
• ISSN: 0103-8478; 1678-4596; 1678-4596
• DOI: 10.1590/0103-8478cr20180053

This study was conducted to evaluate caprine arthritis encephalitis virus (CAEV) transmission among sheep using 15 lambs that were distributed in 2 experimental groups. The exposed group consisted of 10 lambs that remained with their mothers, who were experimentally infected with CAEV. The non-exposed group was characterized as the control group and was comprised of 5 lambs that remained with their CAEV-negative mothers. Blood samples were collected monthly from birth until 1 year of life. To evaluate the transmission, an agar gel immunodiffusion test (AGID), enzyme immunoassay (ELISA), immunoblotting (IB), and nested polymerase chain reaction (nPCR) techniques were used. The non-exposed group was negative in all of the tests throughout the whole experiment. In the exposed group, 2 individuals had positive nPCR results. Positive nPCR samples were sequenced for comparison with the original goat strains and were shown to be similar to the CAEV-Cork strain. Seroconversion was not detected, and clinical manifestations were not observed. Thus, after 1 year of observation, it was verified that CAEV transmission among sheep is possible; however, with discreet frequency. This was an initial study, and other experiments are needed to analyze the adaptive capacity of the CAEV to remain in an infected sheep flock and cause the disease. RESUMO: O estudo foi conduzido para avaliar a transmissão do vírus da artrite encefalite caprina (CAEV) entre ovinos, utilizando 15 cordeiros, distribuídos em dois grupos experimentais. O grupo exposto foi constituído por 10 cordeiros, mantidos com suas mães, que foram infectadas, experimentalmente, com CAEV. O grupo não exposto caracterizou-se como grupo controle e foi formado por cinco cordeiros, mantidos com suas matrizes, negativas para CAEV. Foram colhidas amostras de sangue mensalmente, do periodo que compreende o nascimento até um ano de vida. Para avaliar a transmissão, foram utilizadas as técnicas de imunodifusão em gel de agarose (IDGA), ensaio imunoenzimático (ELISA), immunoblotting (IB) e reação em cadeia da polimerase do tipo nested (nPCR). O grupo não exposto se manteve negativo aos testes durante todo o experimento. Já no grupo exposto, dois indivíduos apresentaram resultados positivos na nPCR. As amostras positivas na nPCR foram sequenciadas para serem comparadas com as cepas originais de caprinos, comprovando se tratar de lentivírus semelhante à cepa CAEV-Cork. A soroconversão não foi detectada e a manifestação clínica