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

bp0009rdr10 | (1) | REDR1986

Function of the epididymis in bulls and rams

Amann R. P.

Abstract unavailable© 1987 Journals of Reproduction & Fertility Ltd...

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...

bp0013cpr15 | Gamete Physiology | CPR1989

Fertilization of pig eggs in vivo and in vitro

Hunter R. H. F. ,

Abstract unavailable© 1990 Journals of Reproduction & Fertility Ltd...

bp0014cpr2 | Regulation of Oocyte and Embryonic Development in Pigs | CPR1993

Nuclear control of early embryonic development in domestic pigs

Prather R. S. ,

In mammals, growing oocytes have characteristically high levels of RNA synthesis. After the initiation of meiosis, that is germinal vesicle breakdown, this RNA synthesis ceases. Although there is limited evidence for RNA synthesis by the zygote, significant amounts of RNA synthesis do not occur until a species-specific cell stage. In pigs, significant amounts of mRNA synthesis cannot be detected before the four-cell stage. There appear to be three qualitatively different ...

bp0015cpr4 | Regulation of Reproductive Function | CPR1997

Mechanisms mediating nutritional effects on embryonic survival in pigs

Foxcroft G. R. , ,

The inconsistency of data from experiments designed to show nutritional effects on embryonic survival is perplexing. However, a number of experimental models have provided some insight into the mechanisms that potentially mediate interactions between nutrition, metabolic state and embryonic survival. The developing ovarian follicle provides the maturational environment for the oocyte, and differences in follicular maturation are associated with differences in the ability ...

bp0015cpr14 | Boar Fertility and Semen Preservation | CPR1997

Sperm plasma membrane characteristics and boar semen fertility

Harrison R. A. P. ,

Much effort is being made to establish relationships between the molecular events that take place in spermatozoa under fertilizing conditions and actual sperm function during fertilization. During capacitation, the process that 'primes' spermatozoa for interaction with the egg, components of the sperm's environment, notably bicarbonate, provoke various specific changes in the architecture and functioning of the sperm plasma membrane in a large number of cells. The individ...

bp0015cpr22 | Aspects of OOcyfe and Embryonic Development in The Pig | CPR1997

Cryopreservationof pig embryos

Dobrinsky J. R. ,

The changing global needs for food and animal products require the development of breeding strategies for maximizing genetic improvement while maintaining genetic diversity. Genetic diversity can be conserved by using separate breeding herds; however, they may be expensive to maintain and inbreeding becomes a major concern. Alternative methods are needed to preserve valuable genetic resources in a reasonable and economic manner. Embryo cryopreservation allows indefinite s...

bp0016cpr8 | OOcyte Development in vitro and in vivo | CPR2001

Basicmechanismsof fertilization and parthenogenesisin pigs

Prather R. S.

Fertilization of the egg, or oocyte, initiates the entire developmental process, but while the mechanism by which the spermatozoa triggers the oocyte to resume meiosis has been studied extensively, conclusions about this process are still elusive. Some workers have suggested that a molecule on the surface of the spermatozoon may interact with a receptor on the plasma membrane of the oocyte, thereby triggering the oocyte to resume meiosis. Other workers have focused on a ...

bp0016cpr12 | Fertilization in vivo and in vitro | CPR2001

In vitro fertilization and embryo development in pigs

Abeydeera L. R.

Considerable progress has been made in the in vitro production of pig embryos using improved methods for in vitro maturation (IVM) and fertilization (IVF). Despite the progress, polyspermic penetration remains a problem for in vitro-matured oocytes. Variation among boars, ejaculates and IVF protocols used in different laboratories appears to influence the incidence of polyspermy. Recent studies indicate that oviduct cells and their secretions p...

bp0016cpr24 | New Technologies | CPR2001

Cryopreservation of pig embryos: adaptation of vitrification technology for embryo transfer

Dobrinsky J. R.

Great advancements in cryopreservation of pig embryos have been made since the last International Conference on Pig Reproduction (ICPR). In 1997, there were standard methods to cryopreserve germplasm and embryos of most livestock species, except for the pig, and development of this technology for use in the international pig industry was slow and in the early stages. Since 1997, there have been advancements in cryopreservation of pig embryos, with reports of production o...