Influence of vitamin E dietary supplementation on some bone characteristics in broiler chicks

ABSTRACT

One hundred and sixty, commercial, one day old, Cobb chicks were randomly allocated into four groups each of forty. The first group was fed on a control diet. The second group was fed on the control diet in which 250 mg vitamin E/kg diet was added. The third group was fed on the control diet in which 500 mg vitamin E/kg diet was added while the fourth group was fed on a control diet in which 750 mg vitamin E/kg diet was added. Several parameters were assessed including body weight development, weight gain, feed consumption and conversion, serum parathyroid hormone and calcitonin, bone Ca, P, S, Mg as well as Mn. Tibia length and weight as well as scanning electron microscope examination of the tibia were recorded. Results indicated that vitamin E supplementation significantly improved body weights starting from the first week of the study throughout the experimental period. All treated groups had better weight gain and feed conversion. Vitamin E supplementation at a level of 250 mg/kg diet significantly [P < 0.05] increased bone P and Mg. Moreover, vitamin E supplementation at a level of 500 mg/kg diet significantly [P< 0.05] increased bone Ca, P, S as well as Mg. In addition, vitamin E supplementation at a level of 750 mg/ kg significantly [P< 0.05] increased bone Ca, P, S, Mg as well as Mn. None of the used levels of vitamin E had any effect on tibia length 7, 28 and 60 days from the beginning of the study. The three used levels of vitamin E significantly [P < 0.05] increased the tibia weight compared to the control group at the age of 60 days. At the age of 28 days, vitamin E supplementation at levels of 500 and 750 significantly [P < 0.05] increased serum calcitonin, while no significant effect was found regarding parathyroid hormone. Moreover, at the age of 56 days, vitamin E and only at a Ievel of 750 mg/kg diet significantly [P < 0.05] increased serum calcitonin and also no significant effect was found regarding parathyroid hormone. The scanning electron micrograph examination of tibia revealed a positive impact of supplemental vitamin E on bone characteristics