The aim of this study was to evaluate the effect of sperm cryopreservation and the maturation state of the oocyte on the time course of canine gamete interaction during co-culture for periods of 1-10 h. Semen samples were obtained by digital stimulation and ejaculates processed as fresh, chilled and frozen samples. Sperm were co-cultured with immature or in vitro mature bitch oocytes for up to ...

In studies of insect cold-hardiness, the supercooling point (SCP) is defined as the temperature at which spontaneous nucleation of body fluids occurs. Despite having an SCP of -20 degrees C, adults of Drosophila melanogaster did not survive exposure to -5 degrees C, which suggests that cold shock causes lethal injury that is not associated with freezing. If, however, flies were chilled at 5 deg...

Artificial Insemination (AI) involves the introduction of sperm into the reproductive tract of the mare without natural mating. AI in the horse was first practiced long ago. Ancient Arabian texts describe how mares were successfully inseminated. In the late 18th Century, an Italian scientist took the idea up again. He performed a series of studies in which he placed stallion semen in the snow a...

BACKGROUND To address a lack of information on the control of ovine helminth parasites in Northern Ireland (NI), a number of research projects have been undertaken, dealing with gastrointestinal nematodes, tapeworms and liver fluke. This investigation concerns Nematodirus and concentrates on three aspects of disease: farm management strategies for its control, derived from the results of a Ques...

Modern livestock breeding is basically dependent on the proper use of semen for artificial insemination (AI) of females and of other reproductive biotechnologies such as the production of embryos in vitro for embryo transfer (IVP). Both these techniques have made possible not only the wide dissemination of genetic material onto breeding populations but also enhanced the selection of best sires,...

Platelet transfusion is a very common lifesaving medical procedure. Not widely known is the fact that platelets, unlike other blood cells, rapidly leave the circulation if refrigerated prior to transfusion. This peculiarity requires blood services to store platelets at room temperature, limiting platelet supplies for clinical needs. Here, we describe the mechanism of this clearance system, a lo...