The aim of the study was presentation the differences in piglets sex proportion in litter and its effect weaning and fattening results. The study was carried out on 133 piglets belonging to 10 litters being progeny of PLW breeding sows and PL boars. Individual piglets growth rate from 1 to 28 day and also during fattening period were recorded. Obtained results were statisticaly analysed including sex proportion. It was showed that in litters was born more gilts (54.89%) than boars (45.11%). Results of weaning piglets to 28 day of life showed higher survival rate of gilts during the weaning period (87.67% vs. 76.67%). Gilts were born heavier as compared to boars (1.35 kg vs. 1.23 kg) and during fattening they achieved higher body weight than barrows (104.48 kg vs. 101.17 kg) (P ≤ 0.05).
