Virus inmunosupresores en aves de traspatio en Uruguay

Resumen

Backyard birds continue to be a means of livelihood for some families in the community of Paysandú, and Río Negro, Uruguay. The objective of this study was to obtain relevant information about the presence of inmunosupresive virus (IV) and the potential impact in the chicken infectious diseases. In total 36 birds were evaluated. Of these, 28 chickens showed clinical symptoms like diarrhea, loss of posture, among others, were aparent, while 8 animals did not present clinical symptoms. All chickens were sacrificed following the protocols established by FAO (FAO, 2006). Presence of the IV were confirmed by serological and molecular technique. Histopathology was performed where macroscopy transformation were associated with immunosuppressive viruses were found in organs such as thymus, spleen, bursa and brain. Using specific molecular technique in tissue samples obtained from chickens, Marek’s disease virus (MEV) was found in 66.6 % (12/18), avian infectious anemia virus (CAV) in 4.44 % (8/18), and avian leukosis virus type A in 33.3 % (6/18). The presence of specific antibodies were demonstrated by specific ELISA technique. It showed specific antibodies against Gumboro (13/18), Avian Infectious Anemia (8/18). Finally Leukosis antigen from Type A variant was detected in 8 animals. Our results showed that Immunosuppressive viruses are widely distributed in backyard birds in the departments of Río Negro and Paysandú. In general, the birds were infected for one or more than one immunosuppressive viruses. The histopathology analysis showed that immunosupresive virus cause pathologies per se (such as lymphoproliferative or degenerative processes in lymphoid organs), as well as immunosuppression that predisposes animals to be infected with important pathogens like Salmonella enteritidis, E. coli and Micobaceterium avium, all of them dangerous zoonosis. These results showed the relevance of inmunosupresive viruses in backyard chickens in Uruguay and the potential impact in the development of infection diseases and mortalities in chicken as well as control of zoonosis.