Efficiency of phytase in growing-finishing pig feeding

摘要

The effect of growing doses of phytase added to feed mixtures for growing pigs on their performance, carcass evaluation, meat quality and bone mineralization was evaluated on 144 pigs allocated to 6 experimental groups, 12 barrows and 12 gilts each. All animals were fed a standard feed mixture. In Group I (PC) the mixture was supplemented with calcium phosphate, Group II (NC) was fed the mixture with no supplement, while Groups III-VI were fed mixtures supplemented with 125, 250,375 or 500 PPU/kg of phytase, respectively.It was found that pigs receiving the highest dose of phytase had significantly better body weight gains than the NC group. There was no difference in feed conversion and carcass traits though animals receiving the lowest dose of the enzyme had the thinnest layer of backfat. The meat of all animals receiving feed without the P supplement, but especially of those from groups NC and 111, had better water holding capacity index than that of the PC group. The highest alkaline phosphatase activity was found in the blood serum of the NC animals. There were also differences in bone wall thickness between NC and group VI receiving the highest dose of phytase. Bones of animals from the NC group had also the lowest yielding load as well as the Ca and P content in the bone cortex.