WCRB2014 POSTER PRESENTATIONS (1) (335 abstracts)
São Paulo State University, UNESP, Botucatu, Brazil.
The aim of this study was to analyze the effects of refrigeration and cryopreservation on dog sperm special on sperm motility and mitochondrial membrane potential (MMP). A total of 15 ejaculates, first and second fractions, were collected from five dogs. Semen was diluted (80×106 sptz/ml) on Tris-egg-yolk medium with 8% of glycerol (one step), filled into 0.5 ml French straw and refrigerated at 5 °C for 1 h. After straws were suspended 6 cm above liquid nitrogen for 20 min and plunged. At each stage (after collection (FS), cooling (CS), and cryopreservation (FTS)) sperm total motility (TM), progressive motility (PM), and % of rapids (RAP) were accessed by CASA and the MMP by flow cytometerusing 1 μl of 1.53 mM JC-1 stain in DMSO (incubated for 30 min at 37 °C).
Statistics: KolmogorovSmirnov, variance and Dunns tests. Results: FS, TM 85%±7, PM 67%±9, RAP 80%±9; high MMP (HMMP)85.1%±1.0; low MMP (LMMP)14.8±1.0. CS: TM 86%±5, PM 68%±9, and RAP 78%±8; HMMP 60.5±2.4; LMMP 39.5±2.4. FTS: TM 72%±12, PM 55%±11, and RAP 63%±13; HMMP 38.1±1.6; LMMP 62.0±1.6. There were significant (P<0.0001) differences between all groups, showing that refrigeration and cryopreservation chances sperm structures. We conclude that despite acceptable motility refrigeration and cryopreservation cause damage to sperm mitochondrial membrane and this could impair spermatozoa life spam.