The transfer of parthenogenetic embryos following artificial insemination in cows can enhance pregnancy recognition via the secretion of interferon tau.

Repeat breeding is a reproductive disorder in cattle. Embryo transfer following artificial insemination (AI) improves pregnancy rate by replenishing interferon tau (IFNT), but it results in a notably higher rate of twin occurrence. This study hypothesized that parthenogenetic (PA) embryo transfer following AI (AI + PA) could improve the conception rate because that PA embryo become as a supplemental source of IFNT without twins.

Improvement of fertility in repeat breeder dairy cattle by embryo transfer following artificial insemination: possibility of interferon tau replenishment effect.

Repeat breeder cattle do not become pregnant until after three or more breeding attempts; this represents a critical reproductive disorder. Embryo transfer (ET) following artificial insemination (AI) in repeat breeder cattle reportedly improves pregnancy rate, leading to speculation that interferon tau (IFNT) is associated with this phenomenon. However, the reason why the conception rate improves remains unknown.

Clinical study report on milk production in the offspring of a somatic cell cloned Holstein cow.

This study examined two female offspring of a somatic cell cloned Holstein cow that had reproduction problems and milk production performance issues. The two offspring heifers, which showed healthy appearances and normal reproductive characteristics, calved on two separate occasions. The mean milk yields of the heifers in the first lactation period were 9,037 kg and 7,228 kg.

Ultrasonographic monitoring of nuclear transferred fetal weight during the final stage of gestation in Holstein cows.

Dystocia or stillbirth accompanied by Large Offspring Syndrome (LOS) occurs rather frequently in Holstein nuclear transferred calves. In regard to prophylaxes, nuclear transferred Holstein fetuses were monitored with ultrasonography during the final stage of gestation. Fetal weight was estimated weekly based on the fetal metacarpal width using ultrasonography.