EFFECT OF DOSAGE OF VITAMIN E ON PHYSIOLOGICAL AND BLOOD PARAMETERS IN GROWING ARBOR ACRES PULLETS UNDER HUMID TROPICAL CONDITIONS

Abstract

One hundred and forty four growing Arbor Acres broiler breeder pullets were used to determine the effect of vitamin E (dL-α-tocopheryl acetate; VE) on the physiological and blood responses. The birds aged 21d were randomly assigned to 4 treatments consisting 0, 50, 100, 150mgVE/kg of diet, with 3 replicates per treatment till d84. Data obtained for rectal temperature (RT), heart rate (HR), respiratory rate (RR), skin temperature under wing (STW) and on the breast (STB), haematology and plasma biochemistry were subjected to analysis of variance. In female chickens, VE significantly (p<0.05) affected HR, STW, WBC, heterophil, lymphocyte and H/L ratio but did not affect RT, RR, STB, PCV, RBC, Hb concentration,
eosinophil, monocyte, basophil, MCV, MCH, MCHC and biochemical parameters. Only pullets on 100mg/kg VE had lower HR than the control group. For STW, 50mg/kg VE had lower value than the control. VE, irrespective of dosage, increased (p<0.05) WBC and lymphocyte in pullets compared to control group. Except in 100mg/kg feed group, heterophil and H/L ratio in 50 and 150mg/kg feed recorded lower values than the control. VE administration of at least 50mg/kg feed in the diet of growing broiler breeder chickens might help in decreasing skin temperature, improving immunity and reducing stress under hot conditions.