A study was carried out to determine the impact of bioproduct Pharselenzym supplementation in diets to performance of sows, growth and resistance of piglets. 27 pregnant sows with 200 - 220kg body weight, 3-4th pregnant times were randomly divided into three groups. A group consists of 3 sub-groups with 3 sows per each sub-group. The groups were correcponded to three dietary treatmens (DC, TN 1, TN2). Group of TN 1 is added bioproduct Pharselenzym 15 days (from 100 days of pregnancy to born), group of TN2 is an additional 30 days (from 85 days of pregnancy to borm), supplementing dose was 1g bioproduct Phar/5kg body weight
group DC without added. This experiment was repeated three times. During the trial, piglets were weighted at the born and at the end 10 days each. The results showed that additional bioproduct Pharselenzym for sows at the pregnant period from 85 and 100 days to born have the effect of increased fetal growth, birth weight of piglets were higher than DC 1.04-3.84kg, weaning weight of piglets higher than DC 4.97-14.26kg, the time for return to oestrus shorter than 1.63-2.5 days and their disease registance was higher too.