Abstract
The sex ratios of livebirths and stillbirths in swine were studied with data collected from theformer Koyasu-Noen Farm. A total of 17, 363 animals were examined. They consisted of 12, 785 ofthe Yorkshire breed (Y) and 4, 578 of the Berkshire breed (B). Analysis on sex ratio was performedby the same methods as described in the previous paper.1) The classes which showed a shift of sexratio to either sex were cited mainly in tables. The results obtained are summarized as follows.
The total sex ratio in the two breeds as a whole was 51.8% ( ?? %) and showed a shif t to maleat a 1% significance level. The sex ratios were 51.7 and 52.7% in the Y and B, respectively (Table1). The paternal and maternal individuals which showed a shift of sex ratio in their offspring were9.4 and 6.5%, respectively (Tabies 2 and 3). Their pedigree, however, could not be surveyed. Therate of stillbirths was 7.3% and the sex ratio of stillbirths 55.5% in the two breeds as a whole. Thesex ratio of stillbirths was 54.1% in the Y and 59.3% in the B (Table 4).
