Effects of the addition of oocyte meiosis-inhibiting drugs on the expression of maturation-promoting factor components and organization of cytoplasmic organelles.

The present study evaluated the effects of the blockade of meiosis in bovine oocytes by the cyclin-dependent kinase inhibitors roscovitine (ROS) and butyrolactone-I (BL-I) on nuclear maturation and extracellular signal-regulated kinase 1/2 (ERK1/2), cyclin B1 and p34 protein expression and localization. We also evaluated ultrastructural changes in oocytes. Immature oocytes were obtained from slaughtered bovines and divided into: (1) control (oocytes for in vitro maturation only in tissue culture medium-199 for 24 h), (2) oocytes that were treated with 12.

Treatment with roscovitine and butyrolactone I prior to maturation alters blastocyst production.

This study evaluated the effects of oocyte meiosis inhibitors roscovitine (ROS) and butyrolactone I (BL-I) on in vitro production of bovine embryos. Bovine oocytes were maintained in pre in vitro maturation (pre-IVM) with 25 µM ROS or 100 µM BL-I for 24 h to delay meiosis and for 24 h in in vitro maturation (IVM). Following this treatment, the nuclear maturation index was evaluated.

Effect of Using Two Cryopreservation Methods on Viability and Fertility of Frozen Stallion Sperm.

Studies involving different methods and techniques of cryopreservation and its interactions with the conception rates in artificial insemination (AI) programs are reported in the literature. This study evaluated the sperm kinetics, plasma membrane integrity, and fertility rates of mares inseminated with cryopreserved stallion semen subjected to different freezing methods. For this, four ejaculates from five stallions were collected and frozen in conventional (Styrofoam box) or automated system in Mini-Digitcool ZH 400.

Sperm sexing with density gradient centrifugation in dogs.

Sexed sperm in dogs is of interest because of being polytocous, and as a result, the greatest number of offspring of the same sex can improve the market, although few studies assessing sperm sexing have been performed in this species. The present study, therefore, was conducted to evaluate the effects on sperm quality and the effectiveness of three discontinuous density gradients to separate dog sperm containing X and Y chromosomes. Thirty ejaculates from ten adult dogs were collected by digital manipulation of the penis.

Effect of deslorelin acetate treatment in oocyte recovery and in vitro embryo production in domestic cats.

Objectives The present study investigated the effect of contraceptive treatment with deslorelin acetate on in vitro embryo production and oocyte recovery in domestic queens. Methods Twenty-one mature domestic cats were used. Eleven queens (treated group) and one tom were kept in an experimental cattery, and 10 queens were privately owned (control group).