Effects of glutathione treatments during sperm washing and in vitro fertilization on the in vitro early development of embryos of Japanese Black cattle.

This study was conducted to examine the effects of adding glutathione (1 mM) to media used for sperm washing and in vitro fertilization (IVF) on the improvement of early development of embryos produced using cryopreserved spermatozoa of the less IVF-competent bull (the one considered unqualified as spermatozoa supplier for the production of bovine blastocysts using IVF). The cryopreserved spermatozoa of this bull were characterized by normal motility and lower ATP content and blastocyst productivity than those of IVF-competent bulls. The addition of glutathione to the sperm washing medium was more effective in improving the productivity of blastocysts and ATP content than the addition of glutathione to the IVF medium or no glutathione addition at all (control).

Breeding Profiles at the Periparturient Stage in Captive Red Foxes () Mating Naturally or Subjected to Artificial Insemination in Japan.

Introduction: Breeding profiles at the periparturient stage in red foxes which mated naturally or were subjected to artificial insemination were retrospectively surveyed using 130 vixens during their reproductive seasons of 2012-2017 in Japan.

Material And Methods: Natural mating vixens were encouraged a maximum of three times with the same male, while artificial insemination was conducted using frozen-thawed semen with the bovine semen extender as a diluent.

Results: With natural mating, conception rates after one, two, and three copulations were 55.

Improvement in blastocyst quality by neurotensin signaling via its receptors in bovine spermatozoa during in vitro fertilization.

Previously, we reported that neurotensin (NT), which is expressed in the uterus and oviduct, enhanced bovine sperm capacitation and acrosome reactions. As NT mRNA expression in bovine oviducts increases dramatically in the follicular phase, we hypothesized that NT modulates fertilization and subsequent conception in cattle. The objective of this study was to evaluate the effect of NT on embryo development and blastocyst quality.

Collection and frozen storage of semen for artificial insemination in red foxes (Vulpes vulpes).

This study was conducted on red foxes to determine the appropriate voltage in electroejaculation for semen collection from stud males, and to confirm whether frozen semen with bovine semen extender can be used for artificial insemination. The proper load voltage for electroejaculation was 3-4 V based on semen collection rates and concentrations of spermatozoa. Frozen semen was prepared according to the known procedure for cows.

Glutathione treatment of Japanese Black bull sperm prior to intracytoplasmic sperm injection promotes embryo development.

Intracytoplasmic sperm injection (ICSI) was expected to enable more efficient use of sperm from sires with preferable genetic traits and result in a generation containing a larger number of offspring with superior genetic characteristics in livestock. However, the efficiency of the early development of embryos produced by ICSI is still far from satisfactory in cattle. The present study aimed to investigate the effects of the treatment of cryopreserved sperm with glutathione (GSH) on the early development of embryos produced by ICSI in Japanese Black cattle.

Exogenous neurotensin modulates sperm function in Japanese Black cattle.

Recently, the conception rates after artificial insemination have been pointed out to decline continuously. To overcome this problem, the control of frozen and thawed sperm quality is required. However, the mechanism of bovine sperm functional regulation is still largely unknown.

Improved embryo development in Japanese black cattle by in vitro fertilization using ovum pick-up plus intracytoplasmic sperm injection with dithiothreitol.

The purpose of this study was to determine whether dithiothreitol (DTT) treatment of sperm and ethanol activation improve embryo production by intracytoplasmic sperm injection (ICSI). Further, we compared ICSI with standard in vitro fertilization (IVF) in oocytes obtained from cattle. We demonstrated that DTT reduced the disulfide bond in the bovine sperm head.