Effect of dietary phosphorus and the ratio between calcium and phosphorus on the activities of alkaline phosphatase and serum calcium and phosphorus in miniature pigs (Xiang pig)
Wang F.L.; Zhang M.F.; Chen Q.M.; Liu P.P.; Xu, M.Q.
Acta Zoonutrimenta Sinica 13(1): 36-42
Effects of dietary phosphorus and the ratio between calcium and phosphorus on the activities of alkaline phosphatase (AKP) in serum, duodenum and the sixth rib and on serum phosphorus and calcium levels were evaluated by using 36 growing castrated Xiang pigs, in a 3 x 3 factorial trial involving 9 diets. For the 9 treatment diets, phosphorus levels of 0.3%, 0.6% and 0.9% were combined with three ratios of 1:1, 1.25:1 and 1.5:1 between calcium and phosphorus. The levels of dietary phosphorus and the ratio between calcium and phosphorus in the diets were adjusted with CaCO3, Na2HPO4 and CaHPO4. The activity of AKP in the serum and in the 6th rib decreased significantly as dietary phosphorus level increased from 0.3% to 0.9% (P<0.05), but the activity of duodenal AKP and serum calcium level were not affected by different levels of dietary phosphorus. There were no effects of the ratio between calcium and phosphorus on AKP activity in serum, duodenum or the 6th rib (P<0.05). Serum phosphorus level increased as dietary phosphorus increased and decreased as dietary calcium to phosphorus ratio increased. Serum calcium level was highest with the 1.25:1 calcium:phosphorus ratio.