Effect of time of artifical insemination on fertilization in laying hens.

Fertility rates on the day following insemination, or during a period of 6 days were compared in laying hens inseminated at various times of a day; i.e., 3:00, 7:00, 11:00, 15:00 and 19:00. Undiluted 0.04ml of mixed semen was deposited at about 2-3cm deep into vagina once for each bird. The rates obtained on the day following insemination were 91.1, 81.4, 0, 0 and 0% for groups inseminated at each time as indicated above. Fertile eggs were mostly from hens inseminated before oviposition, and partly from hens of no oviposition. The rates observed during 6 days after insemination were 88.9%, 80.4%, 72.7%, 93.6% and 88.1% for hens inseminated at 3:00, 7:00, 11:00, 15:00 and 19:00, respectively. However, no significant difference appeared between the rates of groups inseminated at 3:00 and 15:00. To obtain high fertility on the day following insemination, it is recommended to inseminate 5 to 7 hours before oviposition or ovulation.