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Showing 1 to 12 of 12 for “"estrus synchronization"”.
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Efficacy of Synthetic Gonadotropin Releasing Hormone Analogs for Control of Ovulation During Estrus Synchronization Protocols
… hydrochloride), for use in beef timed AI synchronization. In Experiment one 342 beef cows from 7 herds were assigned CYS or FAC treatment as part of the Ovsynch protocol (GnRH d 0 and 9, Lutalyse d 7). Cattle treated with FAC had greater tendency (P=.09) to be pregnant at d 45. One …
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Evaluation of long-term CIDR-based estrus synchronization protocols in primiparous two-year-old beef cows
… and ultimately enhance production efficiency. Estrus synchronization and artificial insemination (AI) are important management tools available to producers that facilitate genetic improvement and enhance reproductive efficiency. A list of recommended protocols may be used to facilitate …
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Follicular dynamics, estradiol-17[beta] concentrations, and luteinizing hormone release following norgestomet implant insertion during estrus synchronization with melengestrol acetate
The objective of this experiment was to determine whether norgestomet implant insertion following melengestrol acetate (MGA) administration altered LH pulse frequency and follicular dynamics. Multiparous Angus cows were randomly assigned to receive MGA (.5 mg*cow⁻¹*d⁻¹ ; MGA; n = 14) for 18 d or to …
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Comparison of Luteolysis and Timed Artificial Insemination Pregnancy Rates after Administration of PGF2a in the Muscle or the Ischiorectal Fossa in Cattle
… to female cattle intramuscularly (IM) for the synchronization of estrus. A novel site for administration of PGF2α that improves beef quality assurance is the ischiorectal fossa (IRF). The objective of this study was to determine whether administration of PGF2α in the IRF results in a similar …
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The Vaginal Microbiome Related to Reproductive Traits in Beef Heifers
… pregnancy. </p> <p>Heifers were exposed to an estrus synchronization period, including 12 days of artificial insemination eligibility, and subsequently exposed to bulls for a 50 day breeding season. Vaginal samples were taken at pre-breeding (n=72), during the first (n=72), and second trimester …
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Reproductive performance of Holstein cows treated with prostaglandin F2a, gonadotropin releasing hormone, and recombinant bovine Somatotropin
… of this study was to examine the effects of presynchronization and recombinant bovine somatotropin (rbST) on conception rates following a timed insemination (TAI) protocol in lactating dairy cows. A further objective included the evaluation of the efficacy of the Early Conception Factor (ECF) …
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Using Commercially Available Hormones to Enhance Swine Reproductive Efficiency in Batch Management Systems
… are weaned in 2- to 5- week intervals, making estrus synchronization of new gilts and sows critical to maintaining reproductive efficiency in the herd. The use of commercially available hormones to synchronize estrus in this system has not been extensively studied. This experiment was conducted …
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Changes in vaginal microbiome of beef cows enrolled in estrous synchronization protocols and its relation to fertility
Estrus synchronization (ES) is a valuable technology that can help beef cow-calf producers to overcome infertility caused by prolonged anestrus. Protocols for ES that use progesterone (P4) supplementation are of particular value to cows with prolonged postpartum anestrus as P4 triggers them to …
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Determining the role of nerve growth factor-beta in seminal plasma on bovine reproduction
… in cows. To test this hypothesis, cows underwent estrus synchronization and were randomly allocated to one of two treatment groups: (1) CONT- 12 mL phosphate-buffered saline; or (2) NGF- 296 µg purified NGF in 12 mL phosphate-buffered saline administered intramuscularly at artificial insemination …
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The effects of varying the interval from follicular wave emergence to progestin withdrawal on follicular dynamics and the synchrony of estrus in beef cattle
… on follicular dynamics and the synchrony of estrus. The experimental design was a 2x2x2 factorial with GnRH or estradiol-17 beta (E2) + progesterone (P4), controlled internal drug-releasing device (CIDR) treatment duration, and PG or saline treatment as main effects. Cycling, Angus cows …
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Evaluation of systematic breeding programs in lactating dairy cows
Observing cows in estrus and inseminating them at the optimal time are necessary steps for effective reproductive management of a dairy herd. However, increasing herd sizes can lead to reproductive inefficiency resulting in decreased profits on dairy herds. Synchronization of estrus, through …
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Evaluation of the Hypothalamic Kisspeptin System Throughout the Estrous Cycle and During the Attainment of Puberty in Gilts
… mg of altrenogest daily for 15 d to synchronize estrus. Following estrus synchronization, estrus detection was performed by exposing gilts to a mature boar and the first day gilts stood immobile was denoted d 1 of the estrous cycle. Blood samples were collected via jugular venipuncture on d 1, 4, …