Effects of supplementing Venda hens with vitamin E on egg production, hatchability and chick productivity

A study was conducted to determine the effect of vitamin E supplementation to the diets of Venda hens on egg production, hatchability and chick productivity. The first part of the study determined the effect of vitamin E supplementation to the diets of Venda hens on feed intake, number of eggs, egg weight, egg content, egg hatchability and chick hatch-weight. Supplementation levels of 0, 200, 400, 800 and 1000 mg of vitamin E per kg DM feed were used in a completely randomized design having five replications with two birds per replicate. Vitamin E supplementation did not have any effect (P<0.05) on number of eggs and feed intake of Venda hens. However, egg weight, egg content, hatchability and chick hatch-weight of Venda chickens improved (P<0.05) with vitamin E supplementation. Dietary vitamin E supplementation values for optimal egg white weight, egg yolk nitrogen content, egg white nitrogen content, egg hatchability and number of eggs were 476 (r2 = 0.756), 750 (r2 = 0.170), 750 (r2 = 0.182), 445 (r2 = 0.670) and 113 (r2=0.966) mg of vitamin E per kg DM feed, respectively. The second part of the study determined the effect of vitamin E supplementation to the diets of Venda hens on performance of their progenies between one and seven weeks old. A completely randomized design was used. All the chickens were fed the same commercial grower diet. Dietary vitamin E supplementation to the diets of Venda hens had no effect (P<0.05) on growth rate and mortality of their progenies between one and seven weeks. Feed intake, feed conversion ratio and live weight of progenies improved (P<0.05) with supplementation of vitamin E to the diets of Venda hens. Dietary vitamin E supplementation to the diets of Venda hens did not have any effect (P<0.05) on dry matter intake, dry matter digestibility, nitrogen retention and metabolisable energy of their progenies at seven weeks old. vi The third part of the study determined the effect of vitamin E supplementation to the diets of Venda