Searchable, peer-reviewed, open-access proceedings from bioscience and biomedical conferences

bp0014cpr17 | Components of Prolificacy in Pigs | CPR1993

Genetic basis of prolificacy in Meishan pigs

Haley C. S. , Leel G. J.

Research in France and in the UK confirms the prolificacy of the Chinese Meishan breed to be about three to four piglets greater than that of control Large White females. Crossbreeding studies clearly indicate that this breed difference is due to genes acting in the dam and not in the litter itself. There is high heterosis for litter size in F1 Meishan x Large White crossbred females, such that their litter size is similar to or greater than that of purebred Me...

bp0015cpr9 | Embryonic and Fetal Development in The Pig | CPR1997

Role of uterine immune cells in early pregnancy in pigs

Engelhardt H. , City H. , King G. J.

The immune system discriminates 'self' from 'non-self', and eliminates that which it determines to be non-self. Mammalian pregnancy appears to represent a failure of self-non-self discrimination, yet it is a highly successful reproductive strategy. We present evidence that the immune system of the female pig responds to the challenges of both mating and the presence of conceptuses. Mating induces an influx of inflammatory leukocytes into the endometrial stroma and uterine...

bp0001redr14 | (1) | REDR1980

Hormonal and cellular interactions in follicular steroid biosynthesis by the sheep ovary

Armstrong DT , Weiss TJ , Selstam G , Seamark RF

Summary. Studies of isolated cell types from sheep follicles revealed several functional changes which occur during follicular maturation. Cyclic AMP production by granulosa cells from the smallest follicles studied (1–3 mm diameter) was stimulated by FSH but not by hCG, suggesting functional FSH receptors at this early stage of differentiation. Medium-sized follicles (4–6 mm) responded to both FSH and hCG. Granulosa cells were unable to synthesize a...

bp0002rdr12 | Inhibin | REDR1990

Inhibin and secretion of FSH in oestrous cycles of cows and pigs

Taya K , Kaneko H , Watanabe G , Sasamoto S

Abstract unavailableKeywords: inhibin; oestradiol; cow; pig; FSH© 1991 Journals of Reproduction & Fertility Ltd...

bp0008rdr22 | Oocyte and Follicle | REDR2014

The metabolism of the ruminant cumulus-oocyte complex revisited

Thompson Jeremy G , Gilchrist Robert B , Sutton-McDowall Melanie L

Summary. The progress in understanding the metabolism of the ruminant cumulus-oocyte complex (COC) from large antral follicles has progressed significantly in the past decade. In particular, new insights in the importance of lipid metabolism, ß-oxidation and its relationship to oxidative phosphorylation within oocytes have emerged. This provides opportunities for tapping into the potential yield of ATP from lipid metabolism, as ATP content is a major dete...

bp0010ised3 | (1) | ISED2019

Conserved mechanisms for putting pregnancy on hold in the mouse, mink and tammar wallaby

Fenelon JC , Shaw G , Renfree MB , Murphy BD

Embryonic diapause was first identified over 150 years ago, but many questions still remain about how the external and hormonal controls of embryonic diapause translate into how the uterus conveys information to the embryo. Current evidence suggests that the control of diapause is mediated by components of the uterine secretions. However, the identity of the essential signalling molecule(s) is unknown. The mouse (Mus musculus), the mink (Neovison vison) and t...

bp0013cpr23 | Behavioural Aspects | CPR1989

Mechanisms mediating the stimulatory effects of the boar on gilt reproduction

Hughes P. E. , Pearce G. P. , Paterson A. M.

Keywords: boar exposure; puberty; gilts; pheromones© 1990 Journals of Reproduction & Fertility Ltd...

bp0014cpr18 | Components of Prolificacy in Pigs | CPR1993

Endocrineand follicular studies in Meishan pig

Hunter M. G. , Biggs C. , Faillace L. S.

The enhanced early embryonic survival in Chinese Meishan compared with Large- White gilts may be due, in part, to differences in ovarian and endocrine function, particularly during the periovulatory period. The overall patterns of oestradiol, LH and FSH secretion were not different between Meishan and Large-White hybrid controls during this period, although circulating inhibin concentrations were higher in Meishan gilts. Thus, there appeared to be a decreased sensitivity ...

bp0016cpr1 | Development of The Follicleand Corpus Luteum | CPR2001

Nutritional regulators of the hypothalamic–pituitary axis in pigs

Barb C. R. , Kraeling R. R. , Rampacek G. B.

Nutritional signals are detected by the central nervous system (CNS) and translated by the neuroendocrine system into signals that alter secretion of LH and growth hormone (GH). Furthermore, these signals directly affect the activity of the pituitary gland independently of CNS input. Insulin-like growth factor I (IGF-I), insulin, leptin and specific metabolites, such as glucose and free fatty acids (FFA)', are potential signals of the metabolic status to the brain-pituit...

bp0017cpr3 | (1) | CPR2005

Gene expression in the brain-pituitary adipose tissue axis and luteinising hormone secretion during pubertal development in the gilt

Barb C. R. , Hausman G. J. , Rekaya R.

The occurrence of puberty in the female is due to the interplay of central and peripheral mechanisms in which the hypothalamic-pituitary-ovarian axis regulates growth and gonadal function, as well as adipocyte hormone secretion. Hypothalamic GnRH mRNA expression increased at 3.5 months of age and declined by 6 months of age. Concomitant with the age related reduction in the oestrogen negative feedback on LH secretion was a decline in hypothalamic oestrogen receptor-&alph...