The effect of time of oviposition in relation to insemination on fertility of chicken hens

Previous investigations have shown that the percentage of fertile eggs laid following artificial insemination of chicken hens in the morning is lower than that from hens inseminated in the afternoon (Parker, 1945; Bornstein et al., 1960). A generally accepted explanation is that more hens have hard-shelled eggs in their uteri in the morning. Several investigators have reported that fertility of hens with hard-shelled eggs in their uteri at the time of insemination is lower than that from other hens (Moore and Byerly, 1942; Malmstrom, 1943; Parker, 1945; Bornstein et al., 1960). However, more recent results (Parker and Arscott, 1965) showing that fertility from hens inseminated at 9 p.m. was comparable to that of hens inseminated at mid-afternoon are not in accord with the above explanation since most of the hens inseminated at 9 p.m. had eggs in their uteri at the time of insemination—many with hard shells. This suggests…