Effect of Phytase on Zinc Nutrition in the Young Pig

English researchers evaluated the effect of phytase on the zinc requirement of young pigs. Fifty-four pigs with an average body weight of 7.4kg were fed grade levels of zinc sulfate with and without 700 units of a microbial phytate (Natuphos?)/kg. Microbial phytase enhanced the plasma alkaline phosphatase activity, plasma zinc and bone zinc concentrations. These parameters increased linearly with zinc intake and the slopes were similar with and without supplemental phytase. Using the plasma alkaline phosphatase and zinc concentration as indicators of dietary zinc needs, it would appear that zinc levels in the pig diets could be reduced with microbial phytase additions. The researchers indicate that zinc sulfate addition to a weanling pig (up to 16kg), fed a corn-soybean meal diet, could be reduced from 100-110 mg/kg diet by about 35mg if the diet is supplemented with 700 units of microbial phytase. Bottom line is that phytase additions will impact both the needs for supplemental phosphorus and zinc in formulating swine diets.

Revy, P.S. and co-workers. 2006. Assessment of dietary zinc requirement of weaned piglets fed diets with or without microbial phytase. J. Animal Physiology and Animal Nutr. 90(1): 50-59.