Effects of the Graded Levels of Vitamin D3 on the Serum Protein, Electrolytes and Bone Mineralization of Broilers under Hot Humid Southern Nigeria

Abstract

This study was carried out to determine the effects of graded levels of vitamin D3 on the serum protein, electrolytes and bone mineralization of broilers under hot humid southern Nigeria. Two hundred and forty day old Marshall Broiler chicks were divided into four groups (A - D) of 60 birds each, and each group replicated thrice, with 30 birds per replicate in a completely randomized design (CRD). Broiler starter and finisher diets were formulate in which vitamin D3 extra commercial feed grade vitamin D3 was added at the levels of 0.0% (control) 40, 80 and 100% (manufacturers’ formulation), and offered to the corresponding groups, B – D respectively during 56 days of feeding (28 days each for starter and finisher). At 56 days, three birds from each treatment group were randomly selected and blood samples collected to determine the serum proteins and electrolyte characteristics of the birds. Bone mineralization was also determined using the tibia bone. There were no significant differences between the mineral levels of calcium and phosphorus in the tibia bone across all the treatments. There were however slight numerical increase in serum calcium values with increasing vitamin D3 supplementation, while PO4- followed the reverse trend. In the tibia bone, calcium values decreased, while phosphorus values remained similar to control. It was concluded that with higher levels of vitamin D3 in treatment D, calcium was readily mobilized from the bones and this this correlated with the higher plasma calcium level observed in the same group.