The reproductive activity of various species of mammals is influenced by the sperm subpopulations of their ejaculates. These subpopulations differ in the motility and kinetic characteristics of the sperm and have been related and classified according to their capacity for the fertilization process. The objective of this research was to evaluate the effect of the composition of the semen diluent on the sperm subpopulations of the chilled rabbit semen. The semen of 10 rabbits of the Californian breed (three ejaculated per animal) was obtained. Each ejaculate was divided into four aliquots, which were diluted in one of four diluents, whose basic composition consisted of T1: skim milk and sugars; T2: dextrose, sodium citrate and potassium acetate; T3: sodium caseinates, phosphates and sugars; and T4: tris-citric acid and egg yolk. Each aliquot was kept refrigerated at 16 °C for 72 h. I...

The aim of this study was to evaluate the effect of four separation methods on seminal quality and in vitro fertilizing capacity of equine cryopreserved spermatozoa. Straws of equine cryopreserved semen were used for sperm separation through the Androcoll, CushionFluid, EquiPure and Percoll methods. A Sperm Class Analyzer (SCA®) system was used to determine total motility, progressive motility, curvilinear velocity, linear velocity and average speed. Also, intact acrosome and sperm vitality were evaluated by fluorescence microscopy. In vitro fertilizing capacity was assessed by in vitro fertilization of bovine oocytes with spermatozoa obtained by each separation method.Cleavage rates were determined after three days of in vitro culture. The results were analyzed using generalized linear models (GLM) and means of the four methods were compared using the Tukey test. The CushionFluid was s...

The aim of this study was to evaluate the effect of four separation methods on seminal quality and in vitro fertilizing capacity of equine cryopreserved spermatozoa. Straws of equine cryopreserved semen were used for sperm separation through the Androcoll, CushionFluid, EquiPure and Percoll methods. A Sperm Class Analyzer (SCA®) system was used to determine total motility, progressive motility, curvilinear velocity, linear velocity and average speed. Also, intact acrosome and sperm vitality were evaluated by fluorescence microscopy. In vitro fertilizing capacity was assessed by in vitro fertilization of bovine oocytes with spermatozoa obtained by each separation method.Cleavage rates were determined after three days of in vitro culture. The results were analyzed using generalized linear models (GLM) and means of the four methods were compared using the Tukey test. The CushionFluid was s...