Effect of hCG administration during corpus luteum establishment on subsequent corpus luteum development and circulating progesterone concentrations in beef heifers

2014 ◽  
Vol 26 (3) ◽  
pp. 367 ◽  
Author(s):  
V. Maillo ◽  
P. Duffy ◽  
L. O'Hara ◽  
C. de Frutos ◽  
A. K. Kelly ◽  
...  

This study examined the effect of a single administration of human chorionic gonadotrophin (hCG) on Day 1 to 4 after oestrus on corpus luteum (CL) development and circulating progesterone (P4). Oestrus-synchronized heifers (n = 43) were administered a single intramuscular injection of saline on Day 1 (control) or 3000 IU hCG on Day 1, 2, 3 or 4 after oestrus. Administration of hCG on Day 1 had no effect on CL area, on Day 2 increased CL area from Day 6 to 12 (P < 0.05), on Day 3 increased CL area from Day 9 to 11, while on Day 4 increased CL size on Days 9 and 10 (P < 0.05). Administration of hCG on Day 4 induced the formation of an accessory CL in 89% of heifers, resulting in a significant increase in total luteal tissue area on the ovaries compared with all other groups. Consistent with the effects on the CL, hCG on Day 1 did not affect P4 concentrations, on Day 2 significantly increased P4 compared with the control from Day 6 to 11 (P < 0.05), on Day 3 resulted in a non-significant increase in P4 while hCG on Day 4 increased P4 from Day 8 to 13 compared with the control (P < 0.05). In conclusion, administration of hCG as early as Day 2 after oestrus results in increased P4 in circulation from Day 6, which should have beneficial downstream effects in terms of uterine receptivity and conceptus elongation.

2020 ◽  
Vol 32 (2) ◽  
pp. 177
Author(s):  
K. Hazano ◽  
S. Haneda ◽  
M. Matsui

In cattle, human chorionic gonadotrophin (hCG) is administered at Day 5 post-ovulation to improve fertility. This treatment can induce ovulation of the first-wave dominant follicle (W1DF), from which an accessory corpus luteum (CL) is generated. In addition, hCG has the effect of promoting CL development. It is possible that the locational relationship between the original and accessary CLs influences the effect of hCG on CL development, because the locational relationship of the CLs affects intraovarian blood flow. The present study aimed to clarify whether the locational relationship between the original and accessory CLs influences the effect of hCG on their development. Cross-bred beef heifers (Holstein×Japanese Black, n=56) were used for the present study. The oestrus cycle was synchronized using oestradiol benzoate (EB) and a controlled internal drug release (CIDR)-based program. Briefly, an administration of EB (2mg) with 9-day CIDR insertion was followed by administration of prostaglandin F2a analogue (PGF2a) on the day of CIDR removal, EB (1mg) 1 day after a PGF2a injection, and GnRH 12h after the second EB injection. At Day 5 post-ovulation, the locational relationship between the original CL and the W1DF was confirmed using transrectal ultrasonography (USG), and two groups were defined: ipsilateral group (IG; n=30), in which the CL and the W1DF are in the same ovary, and contralateral group (CG; n=26), in which the CL and the W1DF are in separate ovaries. Moreover, IG and CG were respectively subdivided into two groups, with or without hCG (1500IU) treatment (IG/hCG, n=15; IG without hCG, n=15, and CG/hCG, n=14; CG without hCG, n=12). The diameter and luteal tissue area (i.e. minus the cavity area) of the original CL and the accessory CL were examined at Days 5, 7, and 14, using USG. Two-way repeated-measures ANOVA was used to compare the diameter and luteal tissue area between IG/hCG and IG without hCG, and between CG/hCG and CG without hCG. In CG, the diameter (P&lt;0.01) and luteal tissue area of the original CL (P&lt;0.001) at Day 7 was increased by receiving hCG, while it did not change in IG. The diameter and luteal tissue area of the original CL at Day 14 were not affected by the administration of hCG in either CG or IG. Moreover, for the accessory CL, no difference of the diameter and luteal tissue area was observed between CG and IG. The present study showed that hCG treatment at Day 5 post-ovulation stimulate the growth of the original CL at Day 7, when the original CL and accessory CL are on contralateral sides. Our results suggest that the effect of administration of the hCG at Day 5 post-ovulation on the original CL development depends on the locational relationship between the original and accessory CL (IG or CG). The function of the CL affects the intrauterine environment for embryonic development. Therefore, it is necessary to investigate the effect of the hCG injection at Day 5 on the function of CL (i.e. plasma P4 concentration) in IG and CG, respectively.


2012 ◽  
Vol 24 (3) ◽  
pp. 472 ◽  
Author(s):  
D. Rizos ◽  
S. Scully ◽  
A. K. Kelly ◽  
A. D. Ealy ◽  
R. Moros ◽  
...  

The aim of the present study was to test the hypothesis that elevated concentrations of progesterone (P4) resulting from the induction of an accessory corpus luteum (CL) by human chorionic gonadotrophin (hCG) administration on Day 5 after oestrus would lead to advanced conceptus elongation on Day 14 following embryo transfer on Day 7. The oestrous cycles of cross-bred beef heifers were synchronised and animals were randomly assigned to receive either of two treatments: (1) intramuscular injection of 3000 IU hCG on Day 5 after oestrus (n = 14); or (2) intramuscular injection of saline on Day 5 after oestrus (n = 13). Ovaries were scanned daily by transrectal ultrasonography to assess CL development. Serum concentrations of P4 were determined from daily blood samples collected from the jugular vein. In vitro-produced bovine blastocysts were transferred to synchronised recipients on Day 7 after oestrus (n = 15 blastocysts per recipient). Heifers were killed on Day 14 after oestrus and the uterus was flushed to recover the embryos. Injection of hCG on Day 5 induced ovulation of the dominant follicle in all treated heifers and increased the total area of luteal tissue on the ovary, which was associated with a significant increase (P < 0.001) in serum concentrations of P4 from Day 7 to Day 14. Positive associations were detected between circulating P4 with CL area (within-day correlations ranging from r = 0.45 to r = 0.67) and total area of luteal tissue (within-day correlations ranging from r = 0.65 to r = 0.86) Administration of hCG did not affect the proportion of Day 14 conceptuses recovered. However, compared with the control group, hCG-treated heifers had increased conceptus length (3.91 ± 1.23 vs 5.57 ± 1.02 mm, respectively; P = 0.06), width (1.00 ± 0.06 vs 1.45 ± 0.05 mm, respectively; P = 0.002) and area (5.71 ± 0.97 vs 8.31 ± 0.83, respectively; P = 0.02). Although numerically greater, mean interferon-τ (IFNT) production in vitro did not differ significantly (P = 0.54) between embryos recovered from hCG-treated and control heifers. In contrast, there was a strong positive correlation between individual embryo length (r = 0.76; P < 0.001) and individual embryo area (r = 0.72; P < 0.001) and IFNT production. In conclusion, administration of hCG on Day 5 after oestrus resulted in the formation of an accessory CL and hypertrophy of the original CL, the result of which was an increase in P4 concentrations from Day 7 onwards. These elevated P4 concentrations were associated with an increased conceptus area. Furthermore, conceptus size was highly correlated with IFNT secretion in vitro.


2013 ◽  
Vol 25 (1) ◽  
pp. 202 ◽  
Author(s):  
V. Maillo ◽  
P. Duffy ◽  
L. O'Hara ◽  
C. de Frutos ◽  
A. K. Kelly ◽  
...  

The steroid hormone progesterone (P4) plays a key role in the reproductive events associated with the establishment and maintenance of pregnancy. Elevated concentrations of circulating P4 in the immediate post-conception period have been associated with advanced conceptus elongation, increased interferon-tau production, and greater pregnancy rates in cattle. Several strategies have been employed to supplement the endogenous P4 supplied by the corpus luteum (CL). One such strategy is the administration of human chorionic gonadotropin (hCG) during the early luteal phase (typically Day 5) that induces ovulation of the first wave dominant follicle and formation of a functional accessory CL, in turn leading to increased circulating concentrations of P4. In addition to this effect, hCG also stimulates hypertrophy of the original CL, leading to a significant deviation in P4 concentrations 2 days after administration. The aim of this study was to examine whether administration of hCG earlier during the metoestrus period would lead to an earlier rise in P4 by stimulation of the developing endogenous CL. The oestrous cycles of cross-bred beef heifers (n = 50) were synchronised and those recorded in standing oestrus (Day 0) were assigned randomly to one of 5 treatments and administered a single IM injection of saline on Day 1 after oestrus (Control) or 3000 IU hCG on Day 1, 2, 3, or 4 after oestrus. Daily blood samples were collected from Day 0 to 14 by coccygeal venipuncture to measure serum P4 concentration. The dimensions of the original CL and induced CL, when present, were measured by daily ultrasound scanning beginning on Day 3 after oestrus until Day 14. Data were analysed using the PROC MIXED procedure of SAS (SAS Institute Inc., Cary, NC, USA). In terms of effects on the CL, administration of hCG on Day 1 had no effect on CL area. Administration on Day 2 increased CL area from Day 6 to 12 (P ≤ 0.05). hCG on Day 3 increased CL area from Day 9 to 11, while administration on Day 4 increased CL size on Day 9 and 10 (P ≤ 0.05). Administration of hCG on Day 4 induced the formation of an accessory CL in 89% of heifers, resulting in a significant increase in total luteal tissue area on the ovaries compared to all other groups. Consistent with the effects on the CL, hCG on Day 1 did not affect P4 concentrations. Administration on Day 2 significantly increased P4 compared to the control from Day 6 to 11 (P ≤ 0.05). Administration on Day 3 resulted in a nonsignificant increase in P4, while hCG on Day 4 increased P4 from Day 8 to 13 compared to the control (P ≤ 0.05). In conclusion, administration of hCG as early as Day 2 post oestrus results in increased P4 in circulation from Day 6 which should have beneficial downstream effects in terms of uterine receptivity and conceptus elongation. Funded by Science Foundation Ireland (07/SRC/B1156) and the Spanish Ministry of Science and Innovation AGL2009-11810.


1984 ◽  
Vol 103 (1) ◽  
pp. 107-110 ◽  
Author(s):  
M. G. Hunter

ABSTRACT Human luteal tissue recovered from varying stages of the luteal phase was minced and incubated for 3 h and the effect of human chorionic gonadotrophin (hCG), prolactin and hCG + prolactin on progesterone and oestradiol production measured. While hCG generally enhanced both progesterone and oestradiol synthesis, prolactin alone at either 20 or 200 μg/l had no significant effect on steroidogenesis. When prolactin was added along with hCG in four of six corpora lutea, however, progesterone production significantly increased and in three of six corpora lutea oestradiol production was increased above that induced by hCG alone. It is concluded that prolactin may play some role in the control of steroidogenesis by the human corpus luteum. J. Endocr. (1984) 103, 107–110


1964 ◽  
Vol 15 (3) ◽  
pp. 461
Author(s):  
DR Lamond

After ovarian examination, and enucleation of corpora lutea where possible, groups of beef heifers on farms in the New England region were injected with progesterone in oil for 6 days. This was followed in some experiments by treatment with placental gonadotrophins. Artificial insemination was carried out 3–5 days after the final injection of progesterone. The effects of dose of progesterone, pregnant mare serum gonadotrophin, and human chorionic gonadotrophin on fertility were observed. Fertility was highest in heifers in which the corpus luteum was enucleated prior to injection of progesterone.


1973 ◽  
Vol 57 (2) ◽  
pp. 299-305 ◽  
Author(s):  
D. T. BAIRD ◽  
R. A. COLLETT

SUMMARY The response of the ovine corpus luteum to repeated infusions of luteinizing hormone (LH) or of human chorionic gonadotrophin (HCG) was tested in four ewes with the left ovary autotransplanted to the neck. Constant infusion for 1 h of either LH (100 or 1000 μg/h) or HCG (200 i.u./h) via the ovarian artery stimulated a temporary increase in secretion of progesterone which fell to control levels by 60 min. Ovarian blood flow increased progressively (P < 0·05) throughout the infusion of gonadotrophin in three of the five experiments. A second infusion of either gonadotrophin after a further control hour failed to stimulate progesterone secretion. These results suggest that ovine luteal tissue rapidly becomes refractory to the steroidogenic effect of LH in vivo.


1982 ◽  
Vol 95 (1) ◽  
pp. 65-70 ◽  
Author(s):  
G. J. S. Tan ◽  
R. Tweedale ◽  
J. S. G. Biggs

The effects of oxytocin on dispersed luteal cells from human corpora lutea of the menstrual cycle were studied. Oxytocin at a concentration of 4 mi.u./ml produced a slight increase in basal progesterone production. However, higher oxytocin concentrations (400 and 800 mi.u./ml) markedly inhibited both basal and human chorionic gonadotrophin-induced progesterone production. These data provide evidence for an effect of oxytocin on the human corpus luteum. In view of the inhibitory action of oxytocin, increased secretion of this hormone may be important in the demise of the corpus luteum at the end of the menstrual cycle.


1980 ◽  
Vol 87 (1) ◽  
pp. 123-129 ◽  
Author(s):  
ALBERT RATNER ◽  
G. K. WEISS ◽  
CAROLYN R. SANBORN

Ovarian tissue from immature rats treated with pregnant mare serum gonadotrophin (PMSG) or PMSG and human chorionic gonadotrophin was incubated in Medium 199. Stimulation of the formation of cyclic AMP in follicular and luteal tissue by terbutaline (10−5 mol/l), a selective β2-agonist, was blocked by butoxamine (10−5 mol/l), a selective β2-antagonist, whereas practolol (10−5 mol/l), a selective β1-antagonist, was ineffective. Propranolol (10−5 mol/l), a non-selective β-antagonist, butoxamine nor practolol affected the increase in cyclic AMP promoted by the addition of 1 μg LH. Stimulation of the production of progesterone in both follicular and luteal tissue by terbutaline was blocked by butoxamine, but not by practolol. These findings indicated that β-adrenergic stimulation of ovarian cyclic AMP and progesterone is mediated by β2-adrenergic receptors.


Reproduction ◽  
2012 ◽  
Vol 143 (5) ◽  
pp. 673-682 ◽  
Author(s):  
L O'Hara ◽  
S Scully ◽  
V Maillo ◽  
A K Kelly ◽  
P Duffy ◽  
...  

The aim of this study was to investigate, in unstimulated and superstimulated heifers, the effect of follicle aspiration just before ovulation on corpus luteum (CL) development, circulating progesterone (P4) concentrations and the ability of the uterus to support embryo development. Following follicle aspiration or ovulation timed from GNRH administration, CL development was assessed by daily ultrasonography, and CL function was assessed in terms of the capacity to produce P4 and the expression of genes involved in steroidogenesis in luteal tissue. The capacity of the uterine environment to support conceptus development was assessed following transfer and recovery of in vitro-produced embryos. Follicular aspiration just before the expected time of ovulation leads to a significant reduction in CL diameter, CL area and area of luteal tissue. This was associated with a decrease in circulating P4 in both unstimulated and superstimulated heifers. Follicle aspiration leads to a reduction in conceptus length and area on day 14 in unstimulated heifers only. Follicle aspiration leads to a reduction in the expression of LHCGR in luteal tissue from unstimulated heifers compared with those in which the CL formed after ovulation. Superstimulation significantly reduced the expression of STAR in luteal tissue in both ovulated and follicle-aspirated heifers. In conclusion, in stimulated and unstimulated heifers, aspiration of the preovulatory dominant follicle(s) just before expected ovulation interferes with the subsequent formation and function of the CL, in terms of size and P4 output and this, in turn, is associated with a reduced capacity of the uterus to support conceptus elongation in unstimulated heifers.


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