Abstract: In order to accurately estimate the fixed and genetic effect of mummy we used generalized linear models analyzed breeds, breeding month, litter month, parities, and estimate the heritability of the mummy. The results showed that impact of the breeds in mummy are not significant difference, P = 0.375（P>0.05）.The breeding in the month of August and October appeared high impact than the other months, the value of fixed-effects were 1.592 and 1.658, respectively. The litter month of May and July had produced a greater impact on give birth mummy, the value of the fixed-effects were 1.399 and 0.906. The influence of the first parity on mummy was more previous than first four parities, the effect of the value was －0.507. The fifth parity showed the highest impact on mummy, the fixed value was 0.073. After fifth parity with increase of parity the impact of give birth mummy was decreased. The heritability of mummy was 0.38. The environment had great impact on mummy except disease (P＜0.01), next important effect was parity (P＜0.05), the breeds didn’t showed significant effect on mummy (P＞0.05).

Key words:

sow; mummy; breeds; breeding month; month of birth; parities; heritability