Active Immunization of Gilts against Gonadotropin-releasing Hormone: Effects on Secretion of Gonadotropins, Reproductive Function, and Responses to Agonists of Gonadotropin-releasing Hormone1

Esbenshade, K. L.; Britt, J.H.

doi:10.1095/biolreprod33.3.569

Cited by 74 publications

(39 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Recently, however, it has been reported that active immunization against LHRH in gilts resulted in decreased plasma levels of gonadotropins and gonadal steroids, with cessation of estrous cyclicity (Esbenshade and Britt, 1985).…”

Section: Discussionmentioning

confidence: 99%

Effect of Active Immunization against LHRH or LH in Boars: Reproductive Consequences and Performance Traits

Falvo

Chandrashekar

Arthur

et al. 1986

Journal of Animal Science

View full text Add to dashboard Cite

Forty crossbred boars were equally divided into eight groups at birth. Four groups were immunized (200 ~g/boar) at 12 wk of age against either luteinizing hormone-releasing hormone (LHRH) conjugated to human serum globulin (LHRH-hSG) in complete Freund's adjuvant (CFA), LHRH-hSG in muramyldipeptide adjuvant (PEP), procine luteinizing hormone (LH) conjugated to hSG (pLH-hSG) in CFA or ovine LH (oLH) in CFA. Equal doses of boosters were given in either PEP or incomplete Freund's adjuvant (IFA) at 16 and 18 wk of age. Two groups of boars were immunized with either hSG + CFA or hSG + PEP (adjuvant controls). Two groups were castrated either at the time of weaning (castrate weaning) or at 16 wk when immunized boars were given their first booster injections (castrate booster). All pigs were slaughtered at 24 wk of age. Serum levels of LH and testosterone (T), LHRH or LH antibody titers, as well as testicular and accessory sex gland weights and histology were determined. By wk 16, LHRH antibody titers began to rise in those boars immunized against LHRH-hSG. Luteinizing hormone-releasing hormone antibody titers on wk 18, 20 and 22 were greater than those at wk 16. By 22 wk of age, LHRH-hSG boars had non-detectable plasma LH and T and reduced weights of testes and acessory sex glands. Boars immunized against oLH did not respond to treatment, whereas pLH-hSG boars showed a reduction in serum T levels and accessory sex gland weights. Immunization had no effect on average daily gain, hot carcass weights or loin eye area. Animals immunized against LHRH in CFA had increased lOth rib fat (P<.05) when compared with the castrated controls, adjuvant controls and the pLH-immunized boars. The incidence of boar taint was reduced (P<.05) in the LHRH-hSG and pLH-treated boars. We conclude that LHRH imrnunoneutralization resulted in castration-like carcass effects in boars but had no effect on performance characteristics, with the possible exception of backfat thickness. These data demonstrate for the first time that active immunization against LHRH is both feasible and practical as an alternative to surgical castration in boars.

show abstract

Section: Discussionmentioning

confidence: 99%

Effect of Active Immunization against LHRH or LH in Boars: Reproductive Consequences and Performance Traits

Falvo

Chandrashekar

Arthur

et al. 1986

Journal of Animal Science

View full text Add to dashboard Cite

show abstract

“…The manipulation of the reproductive activity through the use of a GnRH vaccination was first developed for farm animals as this method offers an alternative to surgical castration for minimizing sexual and aggressive behaviour, suppressing reproductive function and preventing pregnancy (Esbenshade and Britt 1985). Several studies investigating the effect of GnRH vaccination have been carried out on mares, some documenting effective suppression of ovarian function and oestrous behaviour along with a subsequent reversal of these effects (Tshewang et al 1997), while others documented greater individual variation and a less reliable result (Dalin et al 2002).…”

Section: Immunization Against Gnrhmentioning

confidence: 99%

Managing a mare for breeding and sport

Burger¹,

Wohlfender²,

Imboden³

2008

PHK

View full text Add to dashboard Cite

SummaryNowadays in many horse breeds a successful sporting career is required to make a horse eligible for breeding purposes, this may happen before or during its use at stud. For mares, this means careful planning and optimal management of behavioural and reproductive health, especially with the advent of affordable embryo transfer options that allow exploitation of a mare's reproductive potential without a significant break in her career. Unfortunately, there exist as yet only a few research studies in this field. This review article gives a short overview of the actual state of knowledge and the management options for mares, including behavioural management and control of reproductive function through physical, pharmaceutical or immunological means, as well as management of the mare for simultaneous use in breeding and sport.

show abstract

“…A radioimmunoassay procedure described by Guthrie & Bolt (1983) and modified by Esbenshade & Britt (1985) was used to determine concentrations of follicle-stimulating hormone (FSH). Anti-pFSH (USDA-10-1010), 125I-labelled pFSH (USDA-FSH-PP1) and pFSH (USDA-FSH-B-1) were used as the first antibody, radiolabelled ligand and standard, respectively.…”

Section: Introductionmentioning

confidence: 99%

Effects of human chorionic gonadotrophin on contractile activity of steroid-primed pig myometrium in vitro

Flowers

Ziȩcik²,

Caruolo³

1991

Reproduction

View full text Add to dashboard Cite

Summary. We examined the effects of (a) oestrogen and progesterone on concentrations of luteinizing hormone/human chorionic gonadotrophin (LH/hCG) receptors in uterine smooth muscle in vivo and (b) hCG on spontaneous myometrial contractions in vitro. Ovariectomized gilts received 2 ml corn oil (control; n = 5), 2 mg oestradiol benzoate (n = 6) or 20 mg progesterone (n = 5) for 5 days. Gilts were hysterectomized 8 h after the last injection and longitudinal sections of myometrium were incubated in modified Krebs' solution with 0 or 10 i.u. of hCG (n = 10/gilt) for 4 h at 37\s=deg\Cin 95% O2:5% CO2. After incubation, myometrial sections were placed in a tissue chamber perfused with Krebs' solution and mechanical activity was recorded for 30 min. Cell membrane fractions were prepared from myometrial tissue not used for in-vitro studies and analysed for LH/hCG receptors. Treatment with oestradiol benzoate increased (P < 0\m=.\01) the number of LH/hCG-binding sites compared with gilts receiving corn oil or progesterone. Incubation of myometrium with hCG reduced (P < 0\m=.\01) the frequency and amplitude of spontaneous uterine contractions in gilts treated with oestradiol benzoate. In contrast, hCG had no effect (P > 0\m=.\05) on the pattern of myometrial contractions in gilts given corn oil or progesterone. These results indicate that oestradiol promotes the synthesis of LH/hCG receptors in pig myometrium and incubation of oestrogen-primed tissue with hCG has a quiescent effect on myometrial contractility.

show abstract

Active Immunization of Gilts against Gonadotropin-releasing Hormone: Effects on Secretion of Gonadotropins, Reproductive Function, and Responses to Agonists of Gonadotropin-releasing Hormone1

Cited by 74 publications

References 21 publications

Effect of Active Immunization against LHRH or LH in Boars: Reproductive Consequences and Performance Traits

Effect of Active Immunization against LHRH or LH in Boars: Reproductive Consequences and Performance Traits

Managing a mare for breeding and sport

Effects of human chorionic gonadotrophin on contractile activity of steroid-primed pig myometrium in vitro

Contact Info

Product

Resources

About