Effect of dietary zinc level on serum carotenoid levels, body and shank pigmentation of chickens after experimental infection with coccidia.

Abstract Two experiments were conducted to test the effects of a dietary zinc amino acid complex (Zn-AA) and an anticoccidial drug on Eimeria acervulina or Eimeria tenella infections. In each experiment, 288 day-old Three-Yellow-Chickens were used in a 2 × 3 factorial experimental design. Six groups were arranged randomly to receive three levels of Zn-AA (0, 40, or 80 mg/kg) alone or with salinomycin (60 mg/kg). Additionally an uninfected group was set as negative control. At the age of 21 days birds in Exp. 1 were inoculated with 3 · 104 sporulated E. acervulina oocysts, while birds in Exp. 2 were inoculated with 1.5 · 104 sporulated E. tenella oocysts. In Exp. 1, E. acervulina did not suppress growth performance significantly, but in groups without salinomycin it significantly reduced serum carotenoid levels on day 7 after inoculation and body and shank pigmentation on day 42. Salinomycin medication maintained serum carotenoids and visual colour of inoculated birds, but Zn-AA did not influence these par...