Artificial insemination timing on pregnancy rate of Holstein cows using an automated activity monitoring

Effect of insemination-related factors on pregnancy rate using sexed semen in Holstein heifers

The objectives were to determine the effects of insemination with sexed semen at spontaneous and induced estrus, fixed-time insemination at synchronized estrus, the deposition site, estrous intensity, housing, age, body weight, and bull on the pregnancy rate in Holstein heifers, and to compare the quality traits of sexed sperm with those of unsexed semen. The study was conducted on 3206 heifers...

Maximizing Pregnancy Rates When Using Artificial Insemination

Efficacy of Three Synchronization Protocols on the Pregnancy Rate in Lactating Dairy Crossbred Cows after Fixed Time Artificial Insemination

Background and Objective: Ineffective estrus detection is the foremost limiting factor in the fertility of farmed cattle worldwide. Therefore, this study investigates the effect of three synchronization protocols with Fixed Time Artificial Insemination (FTAI) on the pregnancy rate of crossbred dairy cows. Methodology: Ninety one cows were assigned to four groups where the Body Condition Score (...

Timing of artificial insemination and embryo production in superovulated Holstein cattle

The objective was to evaluate the effect of the first artificial insemination (AI) on the number of viable and degenerated embryos, total embryos and unfertilized oocytes, and fertilization rate in Holstein donor cows. Cows (n=22) and heifers (n=50) were synchronized by the Crestar (Intervet International B.V., Boxmeer, Holland) protocol where 3 mg of norgestomet are implanted subcutaneously in...

Insemination factors affecting the conception rate in seasonal calving Holstein-Friesian cows.

Differences in conception rate to first service between artificial inseminations (AI) carried out by commercial AI operators (CAI) or do-it-yourself operators (DIY), between natural service (NAT) and AI, between different AI sires, and between fresh and frozen-thawed semen, on Irish commercial dairy farms, were studied using logistic regression. The study comprised 12,933 potential first insemi...