EFEITO DE DIFERENTES PROTOCOLOS DE DESCONGELAÇÃO SOBRE O SÊMEN CANINO CRIOPRESERVADO EM DILUIDOR À BASE ÁGUA DE COCO EM PÓ (ACP-106®)

It is known that temperature and thawing velocity can affect sperm quality during freeze-thawing procedures. Thus, the aim of this research was to compare different thawing protocols for canine semen extended in ACP-106® extender and cryopreserved. Ten ejaculates were collected from eight dogs and sperm rich fraction was evaluated regarding volume, concentration, motility, vigor, pH, morphology, acrosomal integrity and hyposmotic swelling test. Then, semen was extended in ACP-106® with 20% egg yolk and 6% glycerol, and frozen in 0.25 mL straws. After one week, one straw was thawed at 37°C/60s, another one at 55°C/5s and a third one at 75°C/8s, and the seminal characteristics were reevaluated. Similar results were observed for all the groups, except for sperm motility which was better preserved at 55°C/5s for up 30min than at 37°C/60s or 75°C/8s. From these results, it is concluded that canine semen extended in ACP -106® is better thawed at 55°C/5s.