title: Thiouracil and antibody titers of chickens from lines divergently selected for antibody response to sheep erythrocytes.
abstract: Chickens from lines selected for high (HA) and low (LA) antibody response to sheep red blood cells (SRBC) were fed ad libitum either a diet containing 0 (control) or .1% thiouracil (TF) throughout two trials. Chicks were injected intravenously with .1 ml of .25% SRBC at 37 days of age in Trial 1, and a booster of the same dosage was given to half of these chicks at 61 days of age. Antibody titers were measured 5 and 3 days after primary and secondary inoculations. In Trial 2, primary inoculations of SRBC were given at 21 and 38 days of age, and chicks were bled 3, 5, 7 and 10 days after inoculation. TF chicks had lower body weights and higher feed efficiencies than controls. Plasma thyroxine (T4) concentrations were similar for both lines, but line by diet interactions were present for plasma triiodothyronine (T3) and T3/T4 ratios. When fed the control diet, T3 concentrations and T3/T4 ratios were higher for line HA than line LA, but the pattern was reversed when thiouracil was fed. Antibody titers to SRBC in both trials were higher for HA than LA chicks, but were similar for TF and control chicks. Persistence of elevated titers appeared to be greater in TF than control chicks. There were no differences between TF and control chicks for heterohphil/lymphocyte ratios.
authors.affiliation: Poultry Science Department, Virginia Tech, Blacksburg 24061.
authors.forename: A
authors.initials: A
authors.lastname: Martin
authors.forename: F M
authors.initials: FM
authors.lastname: McNabb
authors.forename: P B
authors.initials: PB
authors.lastname: Siegel
mesh_terms: D000818:Animals; D000917:Antibody Formation / Q000187:drug effects*; D002645:Chickens / Q000276:immunology*; D004912:Erythrocytes / Q000276:immunology; D005260:Female; D007037:Hypothyroidism / Q000097:blood / Q000139:chemically induced / Q000276:immunology; D008297:Male; D012756:Sheep; D013045:Species Specificity; D013889:Thiouracil / Q000494:pharmacology*; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood
chemical_list: D014284:Triiodothyronine; D013889:Thiouracil; D013974:Thyroxine