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Full-Text Articles in Life Sciences
Comparison Of Three Cidr-Based Fixed-Time Ai Protocols In Beef Heifers, G.A. Bridges, J.A. Walker, S.L. Lake, S.G. Kruse, S.L. Bird, B.J. Funnell, R. Arias, J.K. Grant
Comparison Of Three Cidr-Based Fixed-Time Ai Protocols In Beef Heifers, G.A. Bridges, J.A. Walker, S.L. Lake, S.G. Kruse, S.L. Bird, B.J. Funnell, R. Arias, J.K. Grant
Animal Science Faculty Publications
Several effective fixed-time AI (FTAI) protocols have been developed to facilitate AI in beef heifers that circumvent the need for estrus detection. Among these are the 5-d CO-Synch + controlled intravaginal progesterone insert (CIDR) protocol (5dCO), PGF2α (PG) 6-d CIDR protocol (PG-6dCIDR), and 14-d CIDR-PG protocol (14dCIDR-PG). Although each of these protocols varies in duration and approach to synchronizing estrus and ovulation, each has been reported as an effective method to facilitate FTAI in beef heifers. Therefore, the objective of this study was to compare FTAI pregnancy rates in beef heifers synchronized with these 3 CIDR-based protocols. Virgin beef heifers …
Evaluation Of Reproduction And Blood Metabolites In Beef Heifers Fed Dried Distillers Grains Plus Solubles And Soybean Hulls During Late Gestation, Chanda L. Engel, H. H. Trey Patterson, Ron Haigh, Jason Johnson, Mindy Hubert, Brandi Perry, George A. Perry
Evaluation Of Reproduction And Blood Metabolites In Beef Heifers Fed Dried Distillers Grains Plus Solubles And Soybean Hulls During Late Gestation, Chanda L. Engel, H. H. Trey Patterson, Ron Haigh, Jason Johnson, Mindy Hubert, Brandi Perry, George A. Perry
South Dakota Beef Report, 2006
Dried distillers grains plus solubles (DDGS) contain a significant amount of both undegradable intake protein and fat, which have both been shown to increase reproductive performance when supplemented to heifers during gestation. The mechanisms leading to enhanced reproduction when fat or UIP are supplemented have not been fully defined. The objective of this experiment was to evaluate DDGS or soybean hulls (SBH) fed during the last trimester of gestation on circulating concentrations of growth hormone (GH) and insulin-like growth factor-I (IGF-I) and reproductive efficiency. Ninety-five crossbred heifers were grouped by expected calving date, BW, BCS, and randomly assigned to DDGS …
Comparison Of The Efficiency And Accuracy Of Three Estrous Detection Methods To Indicate Ovulation In Beef Cattle, George A. Perry
Comparison Of The Efficiency And Accuracy Of Three Estrous Detection Methods To Indicate Ovulation In Beef Cattle, George A. Perry
South Dakota Beef Report, 2005
The ability to successfully artificially inseminate cattle requires determining the appropriate time to inseminate. Therefore, detection of standing estrus is a major factor in the success or failure of most artificial insemination programs. The objective of these experiments was to determine the efficiency and accuracy of three estrous detection methods (visual, penile deviated bull, and Estrus Alert estrous detection aids) to determine if animals were going to ovulate. Fifty-three postpartum beef cows were synchronized with an injection of gonadotropin releasing hormone (GnRH) followed by an injection of prostaglandin F2_ (PG) seven days later. Estrus was monitored for 72 hours following …
Effects Of Mga On Prepubertal Crossbred Beef Heifers, L. B. Butler, H. L. Miller, M. B. Long, D. D. Zalesky, D.M. Marshall
Effects Of Mga On Prepubertal Crossbred Beef Heifers, L. B. Butler, H. L. Miller, M. B. Long, D. D. Zalesky, D.M. Marshall
South Dakota Beef Report, 1995
A study was conducted using 55 prepubertal replacement crossbred beef heifers to determine the effect of feeding MGA to prepubertal heifers on age at puberty. No difference (P= .65) was detected between MGA treated heifers versus control heifers for age at puberty. There was no difference (P= .80) in age at conception to A1 for the two groups.
Effects Of Progesterone Or Progesterone And Gnrh Administration On Blood Serum Progesterone, Estradiol And Luteinizing Hormone In Prepuberal Beef Heifers, C. L. Henderson, H. L. Miller, M. B. Long, D. M. Marshall
Effects Of Progesterone Or Progesterone And Gnrh Administration On Blood Serum Progesterone, Estradiol And Luteinizing Hormone In Prepuberal Beef Heifers, C. L. Henderson, H. L. Miller, M. B. Long, D. M. Marshall
South Dakota Beef Report, 1994
A study using twelve prepuberal Angus heifers was conducted to determine the effects that synthetic progesterone with or without gonadotropin-releasing hormone (GnRH) had on blood serum concentrations of progesterone, estradiol, and luteinizing hormone (LH) over a 48-hour period. Four heifers were given an implant containing the synthetic progestogen norgestomet for 9 days. Four other heifers were given a similar implant and also received an injection of GnRH after implant removal. The remaining four heifers served as controls and received no treatment. Serum progesterone and estradiol concentrations did not differ between treatments (P> .8). Heifers receiving norgestomet and GnRH had increased …
Effects Of Administering Progesterone Or Progesterone And Gnrh On Age At Pubery In Crossbred Beef Heifers, C. L. Larson, H. L. Miller, D. M. Marshall, M. B. Long
Effects Of Administering Progesterone Or Progesterone And Gnrh On Age At Pubery In Crossbred Beef Heifers, C. L. Larson, H. L. Miller, D. M. Marshall, M. B. Long
South Dakota Beef Report, 1993
A study using 143 replacement beef heifers was conducted over a 3-year period to determine the effects that progesterone or progesterone and gonadotropin releasing hormone (GnRH) would have on age at puberty in beef heifers. Progesterone treated heifers were 21.8 and 38.9 days younger (P<.05) at puberty than control heifers in the first 2 years of the study, while progesterone plus GnRH treated heifers were 35.4 days (P<.01) and 31.2 days (P<.05) younger than controls. No difference (P>.05) in age at puberty was detected between groups in the third year. While progesterone and progesterone plus GnRH treated heifers had a higher conception rate (P<.01) to Al than controls in the first year of the study, calving records showed they experienced a higher rate of embryonic loss. However, calving rate still remained higher than in the control group. These differences were not observed in the second year and calving data for the final year of the study is currently not available.
Comparison Of Melengestrol Acetate And Prostaglandin With Two Injections Of Prostaglandin For Estrous Synchronization In Beef Heifers, H. L. Miller, J. J. Wagner, R. L. Hanson
Comparison Of Melengestrol Acetate And Prostaglandin With Two Injections Of Prostaglandin For Estrous Synchronization In Beef Heifers, H. L. Miller, J. J. Wagner, R. L. Hanson
South Dakota Beef Report, 1989
Crossbred beef heifers were used to compare conception rate when synchronizing estrus with melengestrol acetate (MGA) and prostaglandin or two injections of prostaglandin. Melengestrol acetate was fed to one group of heifers for 16 days and prostaglandin injected 16 days after MGA removal or two injections of prostaglandin given 11 days apart in the other group. The MGA group had a higher conception rate (Pc.05) to timed Al, but there was no difference between the two groups for the breeding season. It appears MGA with prostaglandin results in increased conception to a timed insemination.
Effects Of Administering Progesterone And Gnrh Before Puberty On Age At Puberty And Reproductive Response In Crossbred Beef Heifers, H.L. Miller, J.J. Wagner, R. Hanson
Effects Of Administering Progesterone And Gnrh Before Puberty On Age At Puberty And Reproductive Response In Crossbred Beef Heifers, H.L. Miller, J.J. Wagner, R. Hanson
South Dakota Beef Report, 1988
One hundred six crossbred heifers were utilized to determine prepubertal treatment of progesterone or progesterone plus Gonadotropin Releasing Hormone (GnRH) on age at puberty, conception to a synchronized estrus and conception during the breeding season. Days to puberty were 369.5 ± 6.2, 363.1 ± 9.9 and 360.4 ± 7.8 or control, progesterone primed and progesterone plus Gonadotropin Releasing Hormone (GnRH), respectively. There was no difference (P>.05) in age of puberty, number cycling before synchronization or conception rate during a 35-day breeding season. The percentage of heifers conceiving to synchronized estrus was lower (P<.10) for control compared to progesterone or progesterone plus GnRH treated heifers. Injecting GnRH at breeding had little (P>.05) effect on increasing conception rates …