Powdered coconut water with cryoprotectant can be used for cooling and future freezing of Tambaqui ( Colossoma macropomum ) sperm

Abstract

The study aims to evaluate the main parameters of extended sperm in a solution of powdered coconut water (ACPTM-104) or glucose, both added or not with cryoprotectants during the following periods of cooling or equilibration time: 0 (time of the dilution), 3, 24, 48, and 72 h. The sperm was maintained at 4°C (cooling temperature) as: un-extended (control) and in six different equilibration media combining two extenders (ACP-104 or Glucose) and two cryoprotectants (methyl glycol or dimethylsulfoxide). After being extended and maintained in different equilibration times, sperm was evaluated for kinetic and morphology parameters. At 0 h, best motility results were found when the sperm was not extended; however, after 48-h of equilibration, the sperm extended in ACPTM-104 (38.24%) showed better motility results than the fresh sperm (24.30%; p < .05). The un-extended, after 72 h of cooling, presented lower motility rate and increased sperm abnormality percentages when compared to the one extended in ACPTM-104 (with or without the addition of cryoprotectants). Thus, tambaqui sperm extended in powdered coconut water can be cooled (4°C) up to 72 h. This study also analyzed tambaqui sperm quality during 72 h of exposure to cryoprotectants, providing data for possible extension of equilibration time when necessary.