Effect of Placental Gonadotropin on Pregnancy Rate in the Bovine

Jf, Wagner; El, Veenhuizen; Lv, Tonkinson; Rp, Rathmacher

doi:10.2527/jas1973.3661129x

Cited by 28 publications

(3 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Nevertheless, firstservice pregnancy rate was greater in heifers administered a single injection of 3,000 IU hOG on d 4 of both the prebreeding estrous cycle and postbreeding than in control heifers. These findings are in contrast to those of Wagner et al (1973), Hansel et al (1976) and Echternkamp and Maurer (1983), who reported that administration of 1,000 to 1,500 IU hCG at the time of breeding had no effect on firstservice pregnancy rate. These data, combined with ours, suggest that the luteal cell is not competent to respond to hOG on d 1, but that it can respond on d 4.…”

Section: "contrasting

confidence: 75%

Systemic Progesterone Concentration Following Human Chorionic Gonadotropin Administration at Various Times during the Estrous Cycle in Beef Heifers

Breuel

Spitzer

Henricks

1989

Journal of Animal Science

View full text Add to dashboard Cite

In Trial 1, 26 heifers were allotted randomly to a control group or one of four groups to receive a single injection of 3,000 IU hCG on d 1, 4, 7 or 10 of an estrous cycle. Heifers next completed a nontreated cycle, and at their third estrus were reallotted to one of the five groups described previously. Estrous cycle length was extended in cycle 1 but was not altered during the nontreated cycle or in cycle 3. Administration of hCG on d 4 or 7 increased (P less than .05) mean serum progesterone (P4) over the first 16 d of the estrous cycle by .9 and .8 ng/ml, respectively. In Trial 2, 23 heifers were allotted randomly to one of two groups to receive a placebo or a single injection of 3,000 IU hCG on d 4 of an estrous cycle. Heifers were inseminated artificially at subsequent estrus. On d 4 postbreeding, treatments were repeated. Administration of hCG on d 4 of the prebreeding estrous cycle increased (P less than .05) mean P4 over the first 16 d by .9 ng/ml, whereas mean P4 over the first 16 d postbreeding was not affected by a second injection of hCG on d 4 postbreeding. Administration of hCG increased (P less than .05) first-service pregnancy rate (92 vs 55%). In conclusion, progesterone concentrations were enhanced by hCG given on d 4 or 7 of the estrous cycle, and pregnancy rate was increased when hCG was administered both on d 4 of the prebreeding cycle and d 4 postmating.

show abstract

Section: "contrasting

confidence: 75%

Systemic Progesterone Concentration Following Human Chorionic Gonadotropin Administration at Various Times during the Estrous Cycle in Beef Heifers

Breuel

Spitzer

Henricks

1989

Journal of Animal Science

View full text Add to dashboard Cite

show abstract

“…Results of experiments on the effect of treatment with hCG on fertility are variable. Brown et al (1973) and Wagner et al (1973) found that injection of hCG at mating increased conception rate in beef heifers, but Hansel et al ( 1979) and Morris et al ( 1976) reported no significant effect of hCG at breeding in lactating cows. Treatment with hCG approximately three days after mating either had no effect or reduced conception rates in beef heifers (Wagner et al, 1973;Morris et al, 1976;Breuel et al, 1990).…”

Section: Discussionmentioning

confidence: 99%

Effect of human chorionic gonadotrophin on dominant follicles in cows: formation of accessory corpora lutea, progesterone production and pregnancy rates

Rajamahendran¹,

Sianangama²

1992

Reproduction

114

View full text Add to dashboard Cite

Thirty-four lactating Holstein cows were randomly assigned to four groups for treatment with human chorionic gonadotrophin (hCG, 1000 iu) at insemination day 0 (n = 8) or 7 (n = 9) or 14 days (n = 9) after insemination or with no hCG treatment (control, n = 8). Ultrasound imaging of the ovaries and plasma progesterone measurements were carried out to determine follicular dynamics and corpus luteum growth and function. Rates of formation of accessory corpora lutea were higher among cows treated on days 0 (three cows), 7 (seven cows) or 14 (four cows) than in the controls (one cow). Total corpus luteum diameter was greater (P less than 0.01) among hCG-treated cows than in controls 7-42 days after insemination. Concentrations of progesterone in plasma were significantly (P less than 0.05) higher in cows treated with hCG on days 7 or 14 than in those treated on day 0 or in controls, at days 18, 35 or 42 after insemination. Seven of the cows treated on day 7 became pregnant, whereas four, four and three cows treated on days 0 or 14 and control cows became pregnant, respectively. The results suggest that hCG treatment at 7 days after insemination could be used to produce accessory corpora lutea, raise plasma progesterone concentration and hence reduce the incidence of early embryonic mortality in cattle.

show abstract

“…Os pulsos de LH durante a fase luteinica do ciclo estral em ovelhas, mulheres e macacos induziu um aumento concomitante na secreção de progesterona pelo CL (RAHE et al, 1980, BACKSTROM et al, 1982FILICORI;BUTLER;CROWLEY, 1984). Sabe-se que a atividade do eCG mimetiza a do FSH e a do LH (LICHT et al, 1979) e que em ruminantes (HERVÉ et al, 2004) WALTON, 1989, WAGNER et al, 1973, NAKAO et al, 1983, BRUEL et al, 1990, LEWIS et al, 1990, SIANANGAMA e RAJAMAHENDRAN, 1992. No estudo realizado por Callesen, Greve, Hyttel (1986), o tratamento de superovulação induziu niveis anormais de LH e os níveis de P4 foram identificados e relacionados com a baixa competência dos oócitos.…”

Section: Grupos De Animaisunclassified

Caracterização ultra-estrutural das células luteínicas bovinas derivadas de tratamento com eCG

Rigoglio¹

View full text Add to dashboard Cite

show abstract

Effect of Placental Gonadotropin on Pregnancy Rate in the Bovine

Cited by 28 publications

References 6 publications

Systemic Progesterone Concentration Following Human Chorionic Gonadotropin Administration at Various Times during the Estrous Cycle in Beef Heifers

Systemic Progesterone Concentration Following Human Chorionic Gonadotropin Administration at Various Times during the Estrous Cycle in Beef Heifers

Effect of human chorionic gonadotrophin on dominant follicles in cows: formation of accessory corpora lutea, progesterone production and pregnancy rates

Caracterização ultra-estrutural das células luteínicas bovinas derivadas de tratamento com eCG

Contact Info

Product

Resources

About