scholarly journals Luteotropic Effect of Equine Chorionic Gonadotropin (eCG) and Human Chorionic Gonadotropin (hCG) in Cows

1999 ◽  
Vol 52 (10) ◽  
pp. 635-638
Author(s):  
Masaki NAGANO ◽  
Shunichi KAMIMURA ◽  
Kanji USHINOHAMA ◽  
Katsumi HAMANA
Keyword(s):  
Chorionic Gonadotropin ◽  
Human Chorionic Gonadotropin ◽  
Equine Chorionic Gonadotropin

scholarly journals De Novo-Synthesized Retinoic Acid in Ovarian Antral Follicles Enhances FSH-Mediated Ovarian Follicular Cell Differentiation and Female Fertility

Endocrinology ◽  
2016 ◽  
Vol 157 (5) ◽  
pp. 2160-2172 ◽  
Author(s):  
Tomoko Kawai ◽  
Noriyuki Yanaka ◽  
JoAnne S. Richards ◽  
Masayuki Shimada
Keyword(s):  
Retinoic Acid ◽  
Vitamin A ◽  
Chorionic Gonadotropin ◽  
Granulosa Cells ◽  
Human Chorionic Gonadotropin ◽  
De Novo ◽  
Active Form ◽  
Developmental Competence ◽  
Deficient Diet ◽  
Equine Chorionic Gonadotropin

Abstract Retinoic acid (RA) is the active form of vitamin A and is synthesized from retinol by two key enzymes, alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH). As the physiological precursor of RA, retinol impacts female reproductive functions and fertility. The expression of Adh1 and Adh5 as well as Aldh1a1 and Aldh1a7 are significantly increased in the ovaries of mice treated with equine chorionic gonadotropin/FSH. The RA receptor is expressed and localized in granulosa cells and is activated by endogenous RA as indicated by LacZ expression in granulosa cells of RA-responsive transgene-LacZ transgenic mice (RA reporter mice). Coinjection of the ADH inhibitor, 4-methylpyrazole, with equine chorionic gonadotropin significantly decreases the number and developmental competence of oocytes ovulated in response to human chorionic gonadotropin/LH as compared with controls. Injections of RA completely reverse the effects of the inhibitor of ovulation and oocyte development. When mice were fed a retinol-free, vitamin A-deficient diet that significantly reduced the serum levels of retinol, the expression of the LH receptor (Lhcgr) was significantly lower in the ovaries of the vitamin A-deficient mice, and injections of human chorionic gonadotropin failed to induce genes controlling ovulation. These results indicate that ovarian de novo biosynthesis of RA is required for the follicular expression of Lhcgr in granulosa cells and their ability to respond to the ovulatory LH surge.

scholarly journals Fertility Rates of Ewes Treated with Medroxyprogesterone and Injected with Equine Chorionic Gonadotropin plus Human Chorionic Gonadotropin in Anoestrous Season

2010 ◽  
Vol 2010 ◽  
pp. 1-4 ◽  
Author(s):  
I. W. Santos ◽  
L. C. Binsfeld ◽  
R. R. Weiss ◽  
L. E. Kozicki
Keyword(s):  
Chorionic Gonadotropin ◽  
Human Chorionic Gonadotropin ◽  
Medroxyprogesterone Acetate ◽  
Artificial Insemination ◽  
Fertility Rates ◽  
Main Effect ◽  
Estrus Detection ◽  
Equine Chorionic Gonadotropin ◽  
Fresh Semen ◽  
Teaser Rams

The aim of the present paper was to investigate the efficiency of the equine chorionic gonadotropin (eCG) plus human chorionic gonadotropin (hCG) associated with medroxyprogesterone acetate (MAP) to estrous ewes synchronization. Ninety Texel ewes were investigated during seasonal anoestrous. The ewes received intravaginal sponges containing MAP (60 mg) for nine days. At the time of sponges' withdrawal, the ewes were divided into three groups (G): (1) receiving 2 mL of saline i.m. (n=30), (2) receiving eCG 400 IU i.m. (n=30), and (3) receiving eCG 400 IU plus hCG 200 IU i.m. (n=30). Twelve h after sponges' removal, teaser rams were used to estrus check and remained with the ewes for 96 h. The artificial insemination was made with fresh semen 10 h after estrus detection. The effect of the treatment was not significant for the estrous rates among the groups: 73%, 90%, and 86%, respectively. The main effect was observed in the pregnancy and lambing rates among the groups: 70%, 86%, 56%, and 80%, 120%, 56%, respectively. Based on these results from our study, the use of the MAP—eCG is the best choice to improve the fertility rate on ewes.

Effect of altering the ratio of exogenous gonadotropins on reproductive performance of primiparous sows during the seasonal infertility period

2019 ◽  
Vol 99 (1) ◽  
pp. 202-205 ◽  
Author(s):  
Nutthee Am-in ◽  
Mongkol Techakumphu ◽  
R.N. Kirkwood
Keyword(s):  
Litter Size ◽  
Chorionic Gonadotropin ◽  
Reproductive Performance ◽  
Human Chorionic Gonadotropin ◽  
Estrus Detection ◽  
Estrus Response ◽  
Equine Chorionic Gonadotropin ◽  
To Receive ◽  
Seasonal Infertility

At weaning, 150 primiparous sows were assigned sequentially to receive 400 IU equine chorionic gonadotropin (eCG) with 200 IU human chorionic gonadotropin (hCG) (Gn600), or 400 IU eCG with 400 IU hCG (Gn800), or served as untreated controls. Compared with control and Gn600, the Gn800 had increased estrus response by day 7 and reduced wean-to-estrus intervals (P < 0.05). Compared with controls, both Gn600 and Gn800 increased numbers of large follicles (≥6 mm) at estrus detection (P < 0.05) and the subsequent farrowing rates (P < 0.05). Litter size was unaffected. These data demonstrate the efficacy of supplemental hCG for alleviating effects of seasonal infertility in primiparous sows.

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