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

bp0015cpr10 | Embryonic and Fetal Development in The Pig | CPR1997

Regulation of conceptus development and attachment in pigs

Geisert R. D. , Yelich J. V. ,

Implantation/placentation in domestic pigs is preceded by synthesis ot oestrogen by the conceptus to maintain functional corpora lutea throughout pregnancy and a rapid morphological transformation of conceptuses from spherical to long filamentous thread-like structures. Initial conceptus expansion, reaching a metre in length, not only delineates the surface area for placental attachment, but also provides the mechanism for delivery of oestrogen to signal events necessary ...

bp0016cpr11 | Fertilization in vivo and in vitro | CPR2001

Gamete adhesion molecules

Millerand D. J. , Burkin H. R.

Despite the importance of fertilization for animal production, species preservation and controlling reproduction, the molecular basis underlying fertilization is not well understood. More progress has been made in mice than in other mammals, but targeted deletion of specific genes in the mouse has often yielded unexpected results. The pig is also a useful animal to study, as large numbers of pig gametes can be acquired easily. However, it appears that the pig zona pelluc...

bp0001redr23 | (1) | REDR1980

The effect of suckling upon the endocrine changes associated with anoestrus in identical twin dairy cows

Smith JF , Payne E , Tervit HR , McGowan LT , Fairclough R , Kilgour R , Goold PG

Summary. Identical twin pairs of dairy cows (one twin being placed with 4 calves for multiple suckling while the other was machine milked) were used to study the hormonal changes associated with anoestrus. Experiments were conducted to examine the effect of multiple suckling on the interval to first oestrus post partum, concentrations of LH and progesterone post partum, and the LH response to LH-RH or oestradiol-17β. The effects of hormo...

bp0015cpr11 | Embryonic and Fetal Development in The Pig | CPR1997

Extracellular matrix and the implantation cascade in pigs

Burghardt R. C. , Bowen J. A. , Newton G. R. , Bazer F. W.

The structural and functional alterations of uterine epithelial cells that permit the apical-apical union of conceptus and uterine epithelium are complex and are likely to involve many different adhesion molecules with distinct but inter-related functions. A number of changes in the molecular composition at the apical surface of uterine epithelial cells associated with the transition from the pre-receptive to the receptive state in the pig uterus are reviewed. Molecules t...

bp0003rdr7 | Maternal-Embryo Interactions | REDR1994

The growth hormone/prolactin gene family in ruminant placentae

Anthony RV , Liang R , Kayl EP , Pratt SL

Ruminant placentae produce at least two distinct subclasses of the growth hormone/prolactin gene family, the placental lactogens and prolactin-related proteins. Placental lactogens have been purified from cattle, goat and sheep placentae, and the amino acid sequences of bovine and ovine placental lactogen are known. Bovine and ovine placental lactogens are structurally more similar to prolactin than they are to growth hormone. In addition, six unique mRNAs have been described ...

bp0004rdr17 | The Corpus Luteum | REDR1998

Intraovarian regulation of luteolysis

Meidan R , Milvae RA , Weiss S , Levy N , Friedman A

The corpus luteum is a transient gland, which is only functional for 17–18 days in the cyclic cow or for up to 200 days in the pregnant cow. Regression of the corpus luteum is essential for normal cyclicity as it allows the development of a new ovulatory follicle, whereas prevention of luteolysis is necessary for the maintenance of pregnancy. Evidence acquired over the past three decades indicated that PGF2α is the luteolytic hormone in ruminants. Neverthe...

bp0005rdr12 | Pre-natal Programming of Lifetime Productivity and Health | REDR2002

Gene expression in the developing embryo and fetus

Taylor J , Fairburn H , Beaujean N , Meehan R , Young L

Determining the stage- and tissue-specific patterns of gene expression shown by the embryo and fetus will provide information about the control of normal development. Identification of alterations in these patterns associated with specific abnormal phenotypes will also be informative regarding the underlying molecular mechanisms. In addition, qualitative and quantitative changes in gene expression that deviate from the norm may provide a potential marker system for predicting ...

bp0007rdr26 | Critical Issues Facing Global Ruminant Production | REDR2010

Physiological differences and implications to reproductive management of Bos taurus and Bos indicus cattle in a tropical environment

Sartori R , Bastos MR , BaruselIi PS , Gimenes LU , Ereno RL

In the current review the main fundamental biological differences in reproductive function between Bos taurus and Bos indicus cattle are discussed. Breed differences regarding puberty, estrous cycle patterns, estrous behavior, acquisition of ovulatory capacity, ovarian structures and reproductive hormones are presented. The main physiological differences that Bos indicus cattle present relative to Bos taurus cattle include: delayed age at pu...

bp0008rdr3 | Genomes, Proteomics, Metabolomics | REDR2014

Proteomics of bovine endometrium, oocytes and early embryos

Deutsch Daniela R , Fröhlich Thomas , Arnold Georg J

Summary. Embryo-maternal communication, as well as recognition and establishment of pregnancy, is predominantly controlled by secretion of hormones and proteins. Furthermore, uterine fluid serves as a histotroph and contains factors essential for embryo development and elongation, making it a meaningful source for proteomic approaches of early embryonic development. The studies included in this review address the analysis of uterine fluid and endometrium durin...

bp0008rdr25 | The Eric Lamming Memorial Session | REDR2014

Ovarian function in domestic ruminants: Mechanistic and translational aspects

Campbell BK , Hernandez-Medrano J , McNeilly AS , Webb R , Picton HM

Abstract. The purpose of this review is to illustrate the critical value of integration of both in vitro and whole animal approaches in order to make real progress in terms of understanding the underlying mechanisms controlling ovarian follicle development and also in utilising domestic ruminants as models for the human in the translational development of interventions to address infertility. In terms of mechanistic aspects, this review concentrates o...