Avaliação espermática pós-descongelamento em tambaqui, Colossoma macropomum (Cuvier, 1818)

Abstract

This work tests freezing procedures of tambaqui, Colossoma macropomum, and efficiency in egg fertilizing. Sperm of a hormonally induced reproducer was collected and stored in assay pipes. The material was diluted in cryoprotectant solutions (dimetilacetamida [DMA], dimetilsulfóxido [DMSO], metanol, propilenoglicol e etilenoglicol) (1:3 ratio: sperm:diluting), and subjected to routine freezing procedures. The motility was evaluated before and after this procedure. Fertilization tests were made with cryopreserved sperm. The motility was evaluated before and after these tests. Fertilization tests were made with the cryopreserved semen. The pre-freezing motility was 80%, and after freezing, it was 20-25% for propilenoglicol and etilenoglicol, 5-10% for DMSO and 5% for DMA and methanol. The fertilization was 76% and 88% for propilenoglicol and etilenoglicol, respectively.