Comparison between powder coconut water (ACP®) and Tris as extenders for canine semen cryopreservation

Abstract

The present study compared powder coconut water (ACP®) and Tris extenders on canine semen cryopreservation by classic evaluation and thermoresistance test. Five stud dogs were submitted to two semen collections by digital manipulation. Sperm fractions were analyzed regarding to its color, volume, sperm concentration, motility, vigor and morphology. Semen samples were divided into two aliquots: the first one was extended in Tris and second one in ACP®. Both extenders contained 20% egg yolk. Samples were cooled to 5ºC, glycerol added (6%), packaged in 0.25mL straws, frozen in nitrogen vapors and finally stored in liquid nitrogen. One week later, thaw was performed at 38ºC per 1min in water bath and new evaluations of sperm motility, vigor and morphology were conducted. Samples were kept at 38ºC in water bath and evaluated at 15 and 30min after thaw. No significant difference was observed between extenders throughout cryopreservation or thawing procedures, as well as during thermoresistance test, concerning to characteristics evaluated. Tris and ACP® were efficient in conserving 50% mobile spermatozoa and 70% morphologically normal sperm after thaw. Thus, ACP® can be used as an alternative extender for canine semen cryopreservation.