ROCK PHOSPHATE IN SWINE DIETS FORMULATED ACCORDING TO THE AVAILABLE PHOSPHORUS

An experiment was conducted to evaluate the effect of the same level o f available phosphorus, in different sources of phosphates in the swin e performance. One hundred and forty-four crossbred swines (Landrace x Large White), both sexes, from 22.0 to 99.2 kg of body weight were us ed. The treatments, in a completely randomized design, were based on c orn-soybean meal diets with bicalcium, tapira, patos and goias phospha tes. The diets were isoproteic and isocaloric. The performance of the pigs fed bicalcium and tapira phosphates were similar (P > 0.05) in al l experimental period but the performance of the pigs fed bicalcium ph osphate were different (P < 0.05), whereas the tapira phosphate was si milar (P > 0.05) to the patos and goias phosphates. The average daily gain and feed gain ratio were 804 and 2.83, 750 and 2.89, 650 and 2.88 , 629 g and 3.04, respectively. The ash percentage in the third metaca rpals was significantly different (P < 0.05) for the same available ph osphorus, with 49.80; 50.43; 52.29 and 48.46%, respectively. The rock phosphate from patos and goias must be decreased in fluorine concentra tion, to improve the utilization of these phosphates in the swine diet s.