Adaptation of the sperm selection assay (SSA) for sexed and not sexed bovine semen samples

CUBILLA, MC; TRIBULO H; DOMINGUEZ E; MORENO, A; GUIDOBALDI, HA; GIOJALAS, LC

Tours

Congreso; 18th International Congress on Animal Reproduction; 2016

ICAR

In the last 30 years, assisted reproduction technology has been widely used in farm animals, whereas artificial insemination, in vitro fertilization and sexed embryo transfer are the most currently applied. However, the success of these technologies is rather low, depending in part on sperm quality, which influences fertilization, embryo development and implantation. In our laboratory, we designed a method to select a sperm subpopulation which is at the best physiological state. The Sperm Selection Assay (SSA) is based on the chemical attraction of those spermatozoa ready to fertilize the egg. The aim of this study was adapt this device for sexed and not sexed bovine semen samples. Bovine semen samples were conventionally thawed, removing the seminal plasma and cryoprotectant by centrifugation or migration-sedimentation technique, respectively. Then, spermatozoa were capacitated in Sp-TALP media at 38,5°C under 5% CO2 on air. The SSA consists of a device with two wells connected by a tube. One well was filled with the sperm suspension and the other with the attractant solution, which diffused inside the connecting tube as a gradient. Several features were tested to run the SSA: timing, sperm concentration, follicular fluid and progesterone concentration, determining the relative sperm accumulation in the well containing the attractant. The level of sperm capacitation (determined by the pharmacological induction of the acrosome reaction) and sperm DNA fragmentation level (determined by the ?Halo sperm test?) were assessed before and after the SSA. Statistical significant differences between treatments were determined by one way ANOVA and Tuckey tests, with a level of significance at p