Physiological, growth, and immune responses of Japanese quail chicks to the multiple stressors of immunological challenge and lead shot.

Exposure to the combination of a contaminant and an immunological challenge during development may greatly increase the impact of either or both of these stressors on an individual. This study investigated the interacting effects of a nonpathogenic immunological challenge and lead shot exposure early in the development of a precocial species. Seventy-one quail (Coturnix coturnix japonica) chicks orally received either one #9 lead shot (0.05 g), four lead shots (0.2 g), or no lead at the age of 8 days. A third of each of these groups of chicks were intraperitoneally injected with either 0.075 ml of 10% chukar (Alectoris graeca) red blood cells (CRBCs), Newcastle disease virus (NDV), or a placebo oil vaccine at 13 and 35 days of age. There was no difference in the survival between any of the lead or antigen treatment groups. Lead concentrations in blood were greater for the lead-dosed groups on day 49 but not on day 128. Growth curves were approximated by Weibull functions; growth parameters did not differ between lead-treated and antigen-treated birds. CRBC antigen increases fluctuating asymmetry (FA) for primary feather five, while NDV reduced FA. Lead did not affect antibody production or cell-mediated immune response. White blood cell numbers increased 7 days after antigen injection on days 27 and 49 of age. Granulocyte numbers were significantly higher for the lead-treated quail than the control quail, and both antigen-treated groups had lower granulocyte numbers than control quail. The treatment groups of combining NDV and lead shot had an average plasma protein 14% lower than other groups. Lead shot in the highest of these doses lowered asymptotic weights, increased hematocrits, lowered plasma protein, and increased granulocyte numbers of quail.