Phytase and vitamin E in the feed of growing pigs: 1. Influence on growth,mineral digestibility and fatty acids in digesta

In a 2 x 2 factorial design, 40 growing-finishing pigs (barrows) from 26 to 106 kg body weighs were used to determine the influence of dietary phytase (0 or 1200 PTU) and/or alpha-tocopheryl acetate (0 or 200 mg) in barley-ma ize-based diets, without supplementary trace elements, on the growth perfor mance, blood parameters and the digestibility of P, Ca, Mg, Fe, Cu, Zn, fat and fatty acids. Daily weight gain was highest (p < 0.001) and feed conver sion ratio lowest (p < 0.01) for pigs fed phytase-supplemented diets. Dieta ry vitamin E had no effect on growth performance. Plasma alkaline phosphata se activity was reduced (p < 0.05), plasma P (p < 0.001) and Fe (p < 0.05) concentrations were increased by dietary phytase. Plasma cc-tocopherol conc entration was increased (p < 0.001) Ly the addition of vitamin E. The diges tibility of P, Ca, Mg, Fe, Cu and Zn was improved (p < 0.01) due to phytase inclusion. The ct tocopherol digestibility was not affected by dietary vit amin E supplementation. The caecal digestibility of fat, monoenic and polye nic fatty acids was reduced (p < 0.05) for pigs fed on diets that were supp lemented with phytase. The combined addition of vitamin E and phytase impro ved the caecal digestibility of dietary fat, oleic and linoleic acid.