Control of Estrus and Ovulation using Subcutaneous Implants and Estrogens in Beef Cattle

Wiltbank, J. N.; Sturges, J. C.; Wideman, D.; LeFever, D.G.; Faulkner, L. C.

doi:10.2527/jas1971.333600x

Cited by 54 publications

(19 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Also, no effect of sire on pregnancy rate was detected (P>.05). In previous studies in which similar treatments were utilized (Wiltbank et al, 1971;Wishart and Young, 1974;Woody and Abenes, 1975;Wishart et al, 1977;Mares, 1978), synchronized animals inseminated either after estrus or at a predetermined time usually tended to have lower pregnancy rates than controls. However, in none of the studies were the decreased conception rates low enough to be considered significant at the 95% confidence level.…”

Section: Syncro-mate-b-treated Heifersmentioning

confidence: 98%

Endogenous Hormone Response and Fertility in Dairy Heifers Treated with Norgestomet and Estradiol Valerate2

Kazmer

Barnes

Halman

1981

Journal of Animal Science

View full text Add to dashboard Cite

Seventy postpuberal dairy heifers were assigned to remain untreated (n = 26) or to receive the Syncro-Mate-B (SMB) treatment (n = 44). Untreated heifers were inseminated at 12 hr after detection of estrus, while SMB-treated heifers were inseminated either at 48 hr after implant removal (group 1) or at 12 hr after detection of estrus (group 2). Jugular blood was collected at regular intervals from four untreated heifers and from 20 SMB heifers. In untreated heifers, estradiol-17 beta (E) was unchanged throughout the estrous cycle. Progesterone (P) reached maximum concentrations during the luteal phase and then declined to less than 2 ng/ml before estrus. Follicle stimulating hormone (FSH) ranged between 50.1 and 100.2 ng/ml during the estrous cycle, then reached a peak (P less than .05) concentration of 516.2 ng/ml coincident with peak luteinizing hormone (LH) concentration at 12 hr after the detection of estrus. In SMB-treated heifers, plasma E increased by 12 hr after injection of estradiol valerate and then declined throughout the rest of the sampling period. P declined to less than 2 ng/ml by 24 hr after administration of the SMB treatment and remained low throughout the sampling period. FSH declined in response to SMB treatment, then reached a peak (P less than .05) concentration coincident with peak LH 40 hr after implant removal. First service pregnancy rates among the untreated, group 1 and group 2 heifers, were 65, 58 and 38%, respectively, and did not differ (P greater than .05). SMB treatment was effective in inducing luteolysis and in suppressing estrus and peak gonadotropin release. Intervals from implant removal until estrus and from implant removal until peak gonadotropin release were highly variable among SMB-treated animals.

show abstract

Section: Syncro-mate-b-treated Heifersmentioning

confidence: 98%

Endogenous Hormone Response and Fertility in Dairy Heifers Treated with Norgestomet and Estradiol Valerate2

Kazmer

Barnes

Halman

1981

Journal of Animal Science

View full text Add to dashboard Cite

show abstract

“…Therefore, researchers investigated the effect of decreasing the duration of progestin treatment in an effort to improve fertility. Wiltbank et al (1971) Conception rates for heifers treated with a norgestomet implant for 9 d were 71 and 61% verses 30 and 35% for heifers treated for 16 d, respectively.…”

Section: Length Of Progestin Treatment and Resulting Fertility Earlymentioning

confidence: 99%

The effects of varying the interval from follicular wave emergence to progestin withdrawal on follicular dynamics and the synchrony of estrus in beef cattle

Utt

Jousan

Beal

2003

Journal of Animal Science

View full text Add to dashboard Cite

The objective of this experiment was to examine the effects of varying the interval from follicular wave emergence to progestin removal on follicular dynamics and the synchrony of estrus. The experimental design was a 2x2x2 factorial with GnRH or estradiol-17 beta (E 2 ) + progesterone (P 4 ), controlled internal drug-releasing device (CIDR) treatment duration, and PG or saline treatment as main effects. Cycling, Angus cows (n=49), on d 6 to 8 of the estrous cycle, were randomly assigned to receive a CIDR treatment for 7 or 9 d. Approximately half of the cows from each CIDR group received either GnRH (100 mcg) or E 2 +P 4 (1 mg E 2 + 100 mg P 4 ) at CIDR insertion. Cows in GnRH or E 2 +P 4 groups were further divided into those that received PG (37.5 mg) or saline at CIDR insertion. All cows received PG (25 mg) 1 d prior to CIDR removal. The interval from follicular wave emergence to CIDR removal was longer for cows treated with GnRH (6.6 d) or a CIDR for 9 d (6.5 d) compared to those treated with E 2 +P 4 (4.7 d) or a 7-d CIDR (4.8 d) (P < 0.05). Cows treated with PG or GnRH at CIDR insertion or a 9-d CIDR had a larger dominant follicle (DF) at CIDR removal than those treated with saline, E 2 +P 4 , or a 7-d CIDR. (P < 0.07). Altering the interval from wave emergence to progestin removal created differences in size of the DF at CIDR removal but did not affect the synchrony of estrus.

show abstract

“…Based on data from the above-cited studies, Wiltbank et al 21 investigated use of polyhydroxy polmer subcutaneous implants to deliver an estrous inhibition agent (norethandrolone, Nor) in combination with EV injected intramuscularly at implantation to regress the CL. Beef heifers were implanted with the Nor implant for 9 days and injected with 5 mg EV at implantation (n = 42) or assigned as untreated controls (n = 62).…”

Section: Syncro-mate-b ®mentioning

confidence: 99%

“…Estrus was detected in 89% of heifers 15-19 days after 540-560 mg P4 but 15-23 days after 700-1120 mg P4 (fat heifers receiving these doses did not express estrus days [15][16][17][18][19][20][21][22][23]. Estrus and corpus luteum (CL) formation were prevented.…”

Section: Introductionmentioning

confidence: 99%

Use of Technology in Controlling Estrus in Cattle

Lehman¹,

Lauderdale²

2014

Bovine Reproduction

View full text Add to dashboard Cite

Control of Estrus and Ovulation using Subcutaneous Implants and Estrogens in Beef Cattle

Cited by 54 publications

References 0 publications

Endogenous Hormone Response and Fertility in Dairy Heifers Treated with Norgestomet and Estradiol Valerate2

Endogenous Hormone Response and Fertility in Dairy Heifers Treated with Norgestomet and Estradiol Valerate2

The effects of varying the interval from follicular wave emergence to progestin withdrawal on follicular dynamics and the synchrony of estrus in beef cattle

Use of Technology in Controlling Estrus in Cattle

Contact Info

Product

Resources

About