Cryopreservation of dorada Brycon moorei sperm with dimethyl sulfoxide

The aim was assess thawed sperm quality of dorada Brycon moorei, cryopreserved with dimethylsulfoxide (DMSO) to three inclusion rate. The sperm was obtained from nine males, kept in captivity in the Repelón Fish Farming Station (Atlántico, Col), were induced with carp pituitary extract (4.5 mg/kg). The semen was diluted with an extender composed of DMSO to three inclusion rates (5%, 10% and 15%); 6% glucose and 12% egg yolk. The sperm was diluted in 1:3, packed in macrotubes of 2.5 mL and freeze with vapors of nitrogen and after three months were thawed at 35°C for 90 s. The fresh sperm was considered as control treatment. The thawed semen was analyzed total motility, types of motility, progressivity, velocities and sperm concentration with the Sperm Class Analyzer SCA® software; further, volume, color and activation time were measured in fresh semen. The fresh sperm showed motility greater than 80% and activation time between 28.5 and 41 s; whereas that sperm concentration ranged between 10188.1 and 14590.2 million/ml. The total motility of thawed sperm was higher when DMSO was included at 5% (40.1±5.0%) or DMSO 10% (43.3±8.7%) (p> 0.05); but with 15% DMSO, were registered the low motility (30.6±7.9%) and the highest percentage of immotile sperm (69.4±7.9%) (p