Improving Reproductive Performance in Dairy Cattle Herds through Pharmacological Intervention in Estrous Cycles
Subject Areas : clinical veterinary science
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Keywords: Dairy Cattle, Reproductive Performance, Pharmacological Intervention,
Abstract :
· GnRH synchronizes new wave emergence only when administered in the presence of a functional dominant follicle.
· Presynchronization protocols that induce the production of a CL before initiation of the Ovsynch protocol are likely to improve fertility in anovular cows.
· Estradiol is usually administered at the initiation of the protocol, concurrent with the insertion of a progestin-releasing device to induce new wave emergence regardless of the phases (i.e. growing, static, or regressing phases)
· Progesterone supplementation between the first GnRH and PGF2α for seven days in Ovsynch protocols enhances estrus/ovulation synchrony and conception in anestrous cows and heifers and in cows with cystic ovaries.
· The utilization of eCG in breeding protocols improves reproductive efficiency in seasonally calving, anestrous cattle.
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