Avaliação metabólica da redução de fósforo inorgânico e supressão de microminerais e vitaminas em dietas com fitase para suínos

Abstract

The experiment aimed to evaluate the effects of diets without micro minerals and vitamins, reduced inorganic phosphorus levels and phytase addition in bone metabolism and renal and hepatic functions in finishing pigs. Forty eight 105-day old females were randomly allotted in six groups: standard diets (T1), composed of corn, soybean meal and wheat meal; standard ration without micro mineral and vitamin supplement (T2); T2 ration with phytase (T3) T2 ration reducing 1/3 of inorganic P with phytase (T4), T2 ration reduced 2/3 of inorganic P with phytase (T5) and T2 ration with complete reduction of inorganic P with phytase (T6). The experiment was carried out in two phases: phase 1: 24 animals slaughtered at 150 days of age (106.65 kg); and phase 2: 24 animals slaughtered at 175 days of age (123.87 kg). The serum parameters evaluated were: total and ionic calcium, phosphorus, calcium/phosphorus ratio, total protein, albumin, AST, GGT, alkaline phosphatase, urea and creatinine. All biochemical parameters were analyzed using commercial kits in an automatic analyzer. The levels obtained for all analyzed parameters ranged within normal established values for this species and age. Inorganic phosphorus decrease in phytase-added diets did not interfere in bone metabolism. Vitamin and mineral supplements withdrawal and progressive decrease of inorganic phosphorus and phytase addition in diets of finishing pigs did not change hepatic or renal function. Micro minerals and vitamin restriction for 60 days during finishing phase in pigs did not lead to clinical changes. KEY WORDS: Bone metabolism, hepatic function, renal function .