Turkey Hen Zinc Source Affects Progeny Immunity and Disease Resistance

Abstract

Progeny immunocompetence and disease resistance from turkey hens receiving dietary supplemental zinc was investigated. Twelve hens received a diet that contained 82 mg/kg Zn. Diets were supplemented with 40 mg/kg Zn sulfate (ZnSO4) or 40 mg/kg Zn methionine (ZnM) and analyzed to contain 122 and 118 mg/kg total Zn, respectively (six replications per treatment). Progeny received a corn and soybean meal diet containing 92 mg/kg Zn. Hens supplemented with ZnM had progeny with heavier (P≤.05) bursa of Fabricius as a percentage of poult body weight (BW). Blood monocytes were isolated from poults at 7 days of age, and hens receiving ZnM had progeny with higher (P≤.01) blood leukocyte Zn concentrations. Cutaneous basophil hypersensitivity response elicited by phytohemagglutinin-P (PHA-P) was higher (P≤.05) in progeny from hens supplemented with ZnM. Subsequent hypersensitivity measurements with PHA-P or pokeweed mitogen did not differ between Zn sources. Macrophage function of poults was evaluated after Bordetella avium inoculation. Poults from hens supplemented with ZnM had higher (P≤.06) percentage macrophages adhered to glass surfaces. However, poults from hens supplemented with ZnM had depressed 21-day BW (P≤.05) after B. avium inoculation. Results indicate that dietary ZnM supplementation to hens may aid progeny immune organ development and enhance nonspecific immunity. However, progeny from hens supplemented with ZnM had a depressed BW after B. avium infection that may have been due to a heightened immune response.