Effect of photoperiod on serum hormone concentrations during the annual reproductive cycle in geese

Abstract

ABSTRACT. The poor egg-laying rate of geese hinders the development of the goose industry; therefore, the reproductive performance of geese is an important area of investigation. To evaluate the relationship between photoperiod, reproductive hormones, and reproductive activity during the egg-laying cycle in geese under natural conditions, we collected blood samples from Sichuan white geese and Xupu geese to quantify changes in prolactin (PRL), estradiol (E2), vasoactive intestinal polypeptide (VIP), follicle stimulating hormone (FSH), gonadotropin-inhibitory hormone (GnIH), and luteinizing hormone (LH). We also calculated the rate of egg laying for the two populations during the egg-laying cycle. We show that the egg-laying rate and the serum concentration of some hormones (PRL, E2, VIP, FSH, GnIH, and LH) differed significantly between the two populations during the pre-laying, laying, and ceased-laying periods. Serum LH concentrations may be associated with maturation of the 2 X.Z. Zhao et al.Genetics and Molecular Research 16 (1): gmr16019266 ovary and oviducts, whereas FSH, PRL, and GnIH play important roles in egg laying. These results provide a useful resource for future studies examining the laying rate in geese.

Effects of Dietary Energy Concentration on Reproductive Hormone Secretion and Gene Expression in the Hypothalamus-Pituitary-Gonad Axis in Laying Geese

“…At 588 days of age, 2 birds per pen were selected, and blood was collected from the wing vein into tube containing 1% heparin, centrifuged at 1,520 × g for 10 min at 4°C; then the supernatant was collected for determination of GnRH, FSH, E 2 and IGF-1. The hormone was determined using the radio-immunoassay method (Zhao et al,2017). One bird per pen was slaughtered by manual exsanguination, the hypothalamus, pituitary and ovary were immediately removed, snap-frozen in liquid nitrogen and then stored at -80°C for gene expression analysis.…”

“…FSH releases are necessary to induce follicular maturation and ovulation in the hen (Imai & Nalbandov, 1971), which can facilitate follicle selection and increase the number of follicles (Palmer & Bahr, 1992). In geese, serum FSH concentrations increased steadily in the pre-laying period, increased rapidly in the laying period, then decreased rapidly in the ceased-laying period (Huang, 2015;Zhao et al, 2017). In the present study, the serum concentration of FSH and its mRNA expression in the pituitary decreased in energetic-restricted birds, implying that deficient energy inhibited FSH secretion and possibly impaired follicle development.…”

“…In duck, E 2 is involved in the regulation of prepubertal follicular development in the ovary of ducks (Ni et al, 2007). A higher concentration of E 2 was determined in the hypothalamus (Huang, 2015) and serum (Zhao et al, 2017) of the geese in the laying period. In the present study, sufficient energy enhanced serum E 2 concentration and its mRNA expressions in the ovary, implying that energy regulates laying possibly through manipulating E 2 secretion.…”

Determination of Annual Plasma Hormone Levels Associated with Reproduction in Long-Day Breeding Domestic Geese

“…Additionally, endocrine mechanisms of seasonal reproduction with circulating hormone changes in short-day Chinese geese were investigated [ 17 , 18 ]. Recently, research on short-day geese plasma hormone levels associated with natural daylight reproduction was presented [ 19 ].…”

Light-exposure at night impairs mouse ovary development via cell apoptosis and DNA damage

“…As a daily and seasonal oscillatory rhythm, photoperiod can alter ovarian development cycle, inhibit or delay the sex maturation of different species [35–37]. At the same time, the endocrine environment and related factors can also be changed by photoperiod, such as changes in the relevant hormone content [38,39]. Light as one of the key external environmental cues can affect the circadian rhythms [40].…”