Phenotypic Relation Growth Rate in Performance Test and Litter Size of Sows

In this study we investigated influence of weight gain level of gilts reached during performance test on the expression of important reproductive traits. For the purpose of research, data on the litter size from 2nd to 9th parity of 700 tested gilts were monitored. Characteristics that were examined are: growth at the end of the test, the number of piglets born alive, stillborn and weaned piglets per parity and a total from 2nd to 9th parity, and the percentage of sows entering the next farrowing. Results obtained in this study indicate that gilts with a lower weight gain in performance test have smaller number of live born (8.8:9.23 p<0.01) and reared piglets (8.46:8.55, p<0.01) in regard to the higher weight gain gilts, but a larger number of stillborn piglets (0.35:0.29). Also, gilts with the lowest weight gain during the performance test had smaller average litter size from 2nd to 9th parity. Even greater difference is determined if the average litter size from 3rd to 7th parity (9.8:10.0 and 10.4) is observed. The largest percentage of sows farrowing for the second time was in gilts with the highest weight gain during the performance test (39.5%: 14.8% and 15.5%) which expressed statistically significant difference (p