Effect of initial insemination and insemination interval on fertility in turkey hens.

Large White turkey hens were used to observe fertility through a 20-week laying cycle (31 to 51 weeks of age), following early initial inseminations (EI) and late initial inseminations (LI). Early initial inseminations were made on Days 13 and 15 following photostimulation with subsequent artificial insemination (AI) every 7 (EI + 7) or 14 (EI + 14) days. Late initial inseminations were made on Days 20 and 22 postlighting with subsequent AI every 7 (LI + 7) or 14 (LI + 14) days. Percent of egg production, fertility, and hatch of fertile eggs were measured following the initial AI in each treatment. No significant differences in egg production were seen between treatments. Percent of fertility was greatest in Weeks 6 to 20 with 7-day AI intervals as compared to 14-day intervals. Early inseminations resulted in higher fertility than LI with 14-day AI intervals, but no difference was observed with 7-day intervals. Greater fertility in EI + 14 hens through 20 weeks of egg production, as compared to LI + 14 hens, seems to lend further support to the concept of enhanced oviduct receptiveness to spermatozoa before egg production commences.