open access

https://hdl.handle.net/2115/79219

Effects of use of conventional and sexed semen on the conception rate in heifers : A comparison study

英語

Sexed semen

2019-09-01

Elsevier

Theriogenology

135

33-37

Conception rate with the use of sexed semen is lower than that with the use of conventional semen, posing a major problem in the dairy industry. The aim of this study was to understand the risk factors that affect the conception rate after artificial insemination (AI) with conventional and sexed semen using field data. The records of the first insemination in Holstein heifers with conventional (n = 41,857) and sexed semen (n = 45,465) in Hokkaido, Japan were analyzed. The mean conception rate after Al from 2012 to 2016 was 56.9% with conventional semen and 47.3% with sexed semen. A multivariable logistic regression model including the effects of year, heifer age, time of the year, semen type, service sire, and their interactions was used to evaluate the interaction effect of heifer age and time of the year by semen type on the conception rate. In the analysis using heifer age, we found that heifers inseminated with sexed semen were approximately 21 days younger than those inseminated with conventional semen. Interestingly, in early, warmer months (Jun, Jul, and Aug), the conception rate after AI with sexed semen significantly decreased compared with that after Al with conventional semen (P < 0.01). Our results showed that more careful implementation of Al is required for a stable conception using sexed semen, particularly during warmer months.

学術雑誌論文

Accepted Manuscript

Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International

© 2019. This manuscript version is made available under the CC-BY-NC-ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0/

0093-691X

1879-3231

AA00862972