title: Rapid induction of hypothyroidism by an avian leukosis virus.
abstract: Infection of 10-day chicken embryos with an avian leukosis virus, RAV-7, resulted in hypothyroidism within 3 weeks posthatching. Histological examination of the thyroids from infected chickens showed an extensive infiltration of lymphoblastoid cells by 7 days posthatching. Areas resembling germinal centers were present in the thyroids of infected chickens by 3 weeks posthatching. Examination of circulating thyroid and pancreas hormones showed a significant reduction in T3 and T4 levels and a trend toward higher insulin levels after 16 days posthatching. T4 supplementation of RAV-7-infected chickens alleviated some aspects of the disease syndrome but did not abrogate all symptoms. Marked involution of both bursa and thymus glands was noted. RAV-7 had an RNA genome of 8.2 kilobases and a polypeptide composition characteristic of an avian leukosis virus. The hypothyroidism followed a dose response to RAV-7 infection.
mesh_terms: D000818:Animals; D001353:Avian Leukosis / Q000150:complications* / Q000473:pathology; D001354:Avian Leukosis Virus / Q000502:physiology*; D002060:Bursa of Fabricius / Q000473:pathology; D002645:Chickens; D007037:Hypothyroidism / Q000209:etiology* / Q000382:microbiology; D012367:RNA, Viral / Q000032:analysis; D013950:Thymus Gland / Q000473:pathology; D013974:Thyroxine / Q000494:pharmacology
chemical_list: D012367:RNA, Viral; D013974:Thyroxine