Endocrine and paracrine control of follicular development and ovulation rate in farm species

Hunter, M. G.; Robinson, Robert; Mann, G.E.; Webb, Robert I.

doi:10.1016/j.anireprosci.2004.05.013

Cited by 215 publications

(165 citation statements)

References 86 publications

Supporting

Mentioning

157

Contrasting

Unclassified

Order By: Relevance

“…4a). Follicular recruitment and selection is coordinated by endocrine and paracrine regulation involving changes in the secretion of gonadotrophins and numerous growth factors (Hunter et al, 2004). The number of codominant follicles and the number of ovulatory follicles can be increased by decreasing the sensitivity of the hypothalamo-pituitary-ovarian axis to the negative effect of oestradiol to maintain the concentration of FSH above the threshold level for longer, thus allowing more time for follicles to pass through the so called, "widened gate" (Baird and Campbell, 1998;Hunter et al, 2004;Scaramuzzi et al, 2011).…”

Section: Discussionmentioning

confidence: 99%

Comparison of follicular dynamics and hormone profiles in Boer goats examined during the breeding and non-breeding seasons in the tropics of Queensland, Australia

Nogueira

Cavalieri

Gummow

et al. 2015

Small Ruminant Research

View full text Add to dashboard Cite

Abstract. This study aimed to describe ovarian follicular dynamics in Boer goats (n = 14) during the breeding and non-breeding seasons in the tropics of Queensland. Progesterone profiles and follicular dynamics were compared over a 21-day period in the non-breeding season and one oestrous cycle in the breeding season. Between September and October, 100% of goats were in anoestrus while between April and May they were all undergoing ovulatory cycles. The number of follicular waves during a 3-week period of monitoring was greater during the non-breeding compared to the breeding season (4.8  0.1 vs 4.1  0.1, respectively; P < 0.05), while the number of codominant follicles (5.6  0.3 vs 6.8  0.3, respectively; P < 0.05), growth rate (0.61  0.05 mm/day vs 0.81  0.05 mm/day, respectively; P < 0.05) and the diameter of the largest follicle measured within follicular waves (6.7  0.1 mm vs 7.8  01 mm, respectively; P < 0.05) were less in the non-breeding compared to the breeding season. During the breeding season the interovulatory interval was 19.7  0.2 days. Total number of small follicles (2 to 3 mm) and the total number of follicles ≥3 mm from Days 2 to 14 of the period of examination were greater (P < 0.05) during the non-breeding compared to the breeding season. In the breeding season, 35.7% of cycling goats showed large anovulatory follicles, which persisted and became luteinized. Ovulatory follicles were derived from the fourth follicular wave in 71% of goats. These results have described differences in characteristics of follicular development in the same Boer goats examined during the breeding and non-breeding seasons. In the non-breeding season, the ovaries remained active and follicles continued to grow to reach the equivalent size of preovulatory follicles. Follicular dynamics in the * Corresponding author. +61 4 8894 3333. Email addresses: daniel.nogueira@embrapa.br , daniel.maianogueira@my.jcu.edu.au 2 breeding season was characterised by the development of larger follicles and greater follicular growth rates. Short oestrous cycles and follicular cysts may reduce ovulation rate in Boer goats in the breeding season.

show abstract

Section: Discussionmentioning

confidence: 99%

Comparison of follicular dynamics and hormone profiles in Boer goats examined during the breeding and non-breeding seasons in the tropics of Queensland, Australia

Nogueira

Cavalieri

Gummow

et al. 2015

Small Ruminant Research

View full text Add to dashboard Cite

show abstract

“…Increased levels of FSH during the follicular phase increase follicular size [39,40] and the size of the CL [38,41], which lead to elevated P4 levels [42].…”

Section: Paritymentioning

confidence: 99%

Effect of a GnRH analogue (Maprelin) on the reproductive performance of gilts and sows

Jong

Kauffold²,

Engl³

et al. 2013

Theriogenology

View full text Add to dashboard Cite

a b s t r a c tThe ability of peforelin (l-GnRH-III) to stimulate follicular growth, FSH release, and estrus in gilts after altrenogest treatment and in sows after weaning was investigated. In three farrow-to-wean herds, with at least 600 sows and average production performance, 216 gilts, 335 primiparous, and 1299 pluriparous sows were randomly allocated to three treatments: peforelin (M group: Maprelin), eCG (F group: Folligon), and physiological saline solution (C group). Animals were treated 48 hours after their last altrenogest treatment (gilts) or 24 hours after weaning (sows). The weaning-to-estrus interval, estrus duration, estrus rate (ER), pregnancy rate, and total born (TB), live born, and stillborn (SB) numbers were recorded and compared between treatments for the different parity groups (gilts and primiparous and pluriparous sows). Follicle sizes were measured in representative animals from each group on the occasion of their last altrenogest treatment or at weaning, and also on the occasions of their first (FS1) and second (FS2) attempted inseminations. Blood samples were taken to determine FSH concentrations at weaning and 2 hours after injection, and progesterone concentrations 10 days after the first insemination attempt. The relative change in FSH concentrations was calculated. Significant differences were found for ER within 7 days of weaning in pluriparous sows (95%, 91%, and 90% for the M, F, and C groups, respectively, P ¼ 0.005). Gilts in the F-group had high TB numbers, and pluriparous sows in the M group had high SB numbers (TB gilts ¼ 13.6, 15.4, and 14.9 [P ¼ 0.02] and SB pluriparous sows ¼ 1.8, 1.4, and 1.7 [P ¼ 0.05] for the M, F, and C groups, respectively). The M group had the highest FS1 (for gilts) and FS2 (for pluriparous sows) values: FS1 ¼ 5.4, 4.9, and 4.9 mm [P ¼ 0.02] and FS2 ¼ 6.8, 5.3, and 6.3 mm [P ¼ 0.03] for the M, F, and C groups, respectively. There were no significant differences between the different treatments within each parity group with respect to any of the other variables. Overall, peforelin treatment had small but positive effects on the ER and follicle growth in certain parity groups but did not seem to affect litter sizes or FSH and progesterone levels in sows on the occasions of the corresponding examinations.

show abstract

“…Insulin-like growth factor (IGF)-1 mediates the transition from gonadotropin responsiveness to dependency via enhancement of gonadotropin receptor expression and stimulation of steroidogenesis (Silva et al 2009;Scaramuzzi et al 2011). Dominant follicles gain ovulatory potential by transition from FSH to LH dependency accompanied by an increase in 17β-oestradiol (E2) in the follicular fluid (Campbell et al 1999;Fortune et al 2004;Hunter et al 2004;Baerwald et al 2012). …”

Section: Introductionmentioning

confidence: 99%

Localisation and endocrine control of hyaluronan synthase (HAS) 2, HAS3 and CD44 expression in sheep granulosa cells

Chavoshinejad

Marei

Hartshorne

et al. 2016

Reprod. Fertil. Dev.

View full text Add to dashboard Cite

The aim of the present study was to investigate the hormonal regulation of hyaluronan (HA) components in sheep granulosa cells. HA components are present in the reproductive tract and have a range of physical and signalling properties related to reproductive function in several species. First, abattoir-derived ovaries of sheep were used to determine the localisation of HA synthase (HAS) 1–3 and CD44 proteins in antral follicles. Staining for HAS1–3 and CD44 proteins was most intense in the granulosa layer. Accordingly, the expression of HAS2, HAS3 and CD44 mRNA was measured in cultured granulosa cells exposed to 0–50 ng mL–1 of 17β-oestradiol and different combinations of oestradiol, gonadotropins, insulin-like growth factor (IGF)-1 and insulin for 48–96 h (1 ng mL–1 FSH, 10 ng mL–1 insulin, 10 ng mL–1 IGF-1, 40 ng mL–1 E2 and 25 ng mL–1 LH.). mRNA expression was quantified by real-time polymerase chain reaction using a fold induction method. The results revealed that the hormones tested generally stimulated mRNA expression of the genes of interest in cultured granulosa cells. Specifically, oestradiol, when combined with IGF-1, insulin and FSH, stimulated HAS2 mRNA expression. Oestradiol and LH had synergistic effects in increasing HAS3 mRNA expression. In conclusion, we suggest that the hormones studied differentially regulate HAS2, HAS3 and CD44 in ovine granulosa cells in vitro. Further work is needed to address the signalling pathways involved.

show abstract

Endocrine and paracrine control of follicular development and ovulation rate in farm species

Cited by 215 publications

References 86 publications

Comparison of follicular dynamics and hormone profiles in Boer goats examined during the breeding and non-breeding seasons in the tropics of Queensland, Australia

Comparison of follicular dynamics and hormone profiles in Boer goats examined during the breeding and non-breeding seasons in the tropics of Queensland, Australia

Effect of a GnRH analogue (Maprelin) on the reproductive performance of gilts and sows

Localisation and endocrine control of hyaluronan synthase (HAS) 2, HAS3 and CD44 expression in sheep granulosa cells

Contact Info

Product

Resources

About