The effects of erythrocyte alloantigen L on the avian immune response

Experiment 1 examined the alloantigen system L effects on Rous sarcomas in three B complex genotypes. The parental stock were 50% Modified Wisconsin Line 3 and 50% inbred Line 6.15- 5. B2B5 L1L2 × B2B5 L 1L2 matings produced experimental chicks. Chicks were inoculated with 20 pock-forming units (pfu) Rous sarcoma virus (RSV) at 6 weeks-of-age. Tumors were scored six times over 10 weeks postinoculation. Tumor scores were used to assign a tumor profile index (TPI) to each chicken. Results were evaluated by ANOVA. The B complex affected the responses. Separate analyses revealed L system effects ( P < 0.05) only in B5B 5 chickens.; Experiment 2 examined the influence of Ea-L on antibody response to SRBC and Brucella abortus (BA). The mating protocol was the same as in Experiment 1. At 4 and 11 weeks of age the experimental birds were injected intravenously with standard concentrations of SRBC and BA. Total and ME-resistant antibody titers were determined as described. Results were analyzed by ANOVA. Ea-L had an effect on total primary antibody titer to SRBC in a B5B 5 background (p < 0.004) and on total (p < 0.011) and ME-resistant (p < 0.017) secondary titer to SRBC in a B5 B5 genotypic background. Ea-L also affected total (p < 0.004) and ME-resistant (p < 0.005) secondary titer to Brucella abortus in a B5 B5 background.; Experiment 3 examined the effect of Ea-L on resistance and acquired immunity to E. tenella infection. The mating protocol was the same as in Experiments 1 and 2. In the resistance and susceptibility study, chicks were weighed and inoculated with 30,000 E. tenella oocysts at 6 weeks of age. 6 days post-inoculation, the birds were weighed again and assigned a cecal lesion score. In the immunity study, the challenge procedure was preceded by inoculations of 500 oocysts per day beginning at 5 weeks. Weight gain and cecal lesion scores were evaluated by ANOVA. The B complex affected lesion score in the immunity but not the resistance and susceptibility study and did not affect weight gain in either study. The L system had no effect in either study.