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

bp0017cpr10 | (1) | CPR2005

Maternal recognition of pregnancy signal or endocrine disruptor: The two faces of oestrogen during establishment of pregnancy in the pig

Geisert R.D. , Ross J.W. , Ashworth J.W. , White F.J. , Johnson G.A. , DeSilva U.

Timing of conceptus growth and attachment to the uterine luminal epithelium is regulated by progesterone secretion from the corpus luteum and by expression of progesterone receptor in the uterine epithelia and stroma. Conceptus growth and uterine attachment are temporally associated with the disappearance of progesterone receptors from uterine epithelia. While the loss of progesterone receptor from the endometrial epithelia on day 10 of the oestrous cycle and pregnancy h...

bp0012cpr14 | Nutrition and Environmental Factors Affecting Prolificacy | CPR1985

Influence of light and photoperiodicity on pig prolificacy

R. Claus and U. Weiler ,

Summary. In the wild pig mating activity is seasonal. The main breeding period is in late autumn but a second period may occur around April. It is known from other species that seasonal variations in breeding activity are mainly regulated by photoperiod.In the domestic pig seasonal influences on prolificacy still exist: for example, Al boars not only show decreased steroid synthesis, sperm counts and libido in summer compared with t...

bp0018cpr1 | Physiological Roles of The Boar Ejaculate | CPR2009

The physiological roles of the boar ejaculate

Rodriguez-Martinez H. , Kvist U. , Saravia F. , Wallgren M. , Johannissono A. , Sanz L. , Pena F.J. , Martinez E.A. , Roca J. , Vazquez J.M. , Calvete J.J.

During ejaculation in the boar, sperm cohorts emitted in epididymal cauda fluid are sequentially exposed and resuspended in different mixtures of accessory sex gland secretion. This paper reviews the relevance of such unevenly composed fractions of seminal plasma (SP) in vivo on sperm transport and sperm function and how this knowledge could benefit boar semen processing for artificial insemination (Al). The firstly ejaculated spermatozoa (first 10 ml of the spe...

bp0007rdr24 | The Ruminant Corpus Luteum | REDR2010

Endocrine actions of interferon-tau in ruminants

Hansen TR , Henkes LK , Ashley RL , Bott RC , Antoniazzi AQ , Han H

The ovine conceptus releases interferon-τ (IFNT), which prevents upregulation of the endometrial estrogen receptor (ESR1) and, consequently, oxytocin receptor (OXTR), thereby disrupting pulsatile release of prostaglandin F2α (PGF) in response to oxytocin. IFNT, through paracrine action on the endometrium, protects the corpus luteum (CL) during maternal recognition of pregnancy. Pregnancy also induces IFN stimulated genes (ISGs) in peripheral blood mononuclear cells (...