title: Interactions between endogenous virus loci ev6 and ev21. 1. Immune response to exogenous avian leukosis virus infection.
abstract: The effects of ev6, ev21, sex, and hatch, were studied with respect to avian leukosis virus (ALV) viremia, cloacal shedding, and antibody response among RPL-40 virus-infected White Leghorns that carried ev6 and ev21 in all combinations. Among the four possible ev genotypes, chickens that carried only ev21 were the most immunologically tolerant to RPL-40 infection. Incidence of RPL-40 viremia was lowest among hatchmates that lacked both ev genes. Analysis of variance indicated significant interactions between ev6 and ev21 with respect to all responses. Among ev21+ slow-feathering (SF) chickens, the incidence of viremia and shedding of RPL-40 was reduced in the presence of ev6 when compared with ev6- hatchmates. Conversely, among ev21- rapid-feathering (RF) chickens, ev6 significantly enhanced the incidence of RPL-40 viremia when compared with ev6- hatchmates. The endogenous virus, ev6, markedly reduced recovery of the endogenous virus (EV21) from plasmas of slow-feathering chickens. When both flocks were terminated at 21 wk of age, significantly more ev21+ SF females had died from or developed RPL-40-induced tumors than ev21- hatchmates.
authors.affiliation: USDA, Agricultural Research Service, East Lansing, Michigan 48823.
authors.forename: E J
authors.initials: EJ
authors.lastname: Smith
authors.forename: A M
authors.initials: AM
authors.lastname: Fadly
authors.forename: L B
authors.initials: LB
authors.lastname: Crittenden
mesh_terms: D000818:Animals; D001353:Avian Leukosis / Q000276:immunology* / Q000635:transmission; D001354:Avian Leukosis Virus / Q000145:classification / Q000235:genetics*; D002645:Chickens / Q000235:genetics* / Q000276:immunology; D005241:Feathers / Q000254:growth & development; D005260:Female; D005814:Genes, Viral / Q000235:genetics*; D008297:Male; D011201:Poultry Diseases / Q000276:immunology*; D012727:Sex Characteristics; D014766:Viremia / Q000235:genetics / Q000276:immunology / Q000662:veterinary*