Post-thaw dilution of Rhamdia quelen sperm improves the reproductive success

Franca, Thales de Souza
Gomes, Itamar Cossina
Sanches, Eduardo Antonio
Atehortua, Maritza Perez
Teixeira, Nathalia Santos
Rodrigues, Romulo Batista
de Freitas, Thaiza Rodrigues
Galuppo, Andrea Giannotti
Quirino, Monike
Benato, Jhony Lisboa
Machado, Thales Lysakowski Flores
Marques, Lis Santos
Bustamante Filho, Ivan Cunha
Bortolozzo, Fernando Pandolfo
Streit Jr, Danilo Pedro
Datos de publicación:
The aim was to evaluate the effect of a post-thaw dilution of Rhamdia quelen sperm in 1.1% NaCl (325 mOsm kg(-1); pH 7.6; 24 degrees C) solution on the quality and reproductive capacity. Sperm from eight males were cryopreservation in nitrogen vapor at -170 degrees C for 18 h in 0.25 mL straws in a freezing medium containing 5% fructose, 5% Powdered milk, and 10% methanol. The samples were thawed and post-thaw diluted (1:20) in NaCl solution or not (control). The higher spermatozoa velocities were observed in the post-thaw diluted samples (curvilinear (VCL) -69 +/- 11 pm s(-1); average path (VAP) -45 +/- 8 pm s(-1); straight-line (VSL) -43 +/- 8 pm s(-1)) compared to the control (VCL -47 +/- 10 pm s(-1); VAP -31 +/- 6 pm s(-1); VSL -30 +/- 6 pm s(-1)). Greater straightness (STR), progression (PROG), and beat cross frequency (BCF) were observed in the post-thaw diluted samples (STR -96 +/- 7%; PROG -666 +/- 128 pm; BCF -42 +/- 2 Hz) than in control (STR -95 +/- 5%; PROG -463 +/- 92 pm; BCF -40 +/- 2 Hz). The strongly curled tail was the only morphology change that differ between the post-thaw diluted (5 +/- 2%) and control (2 +/- 1%). Membrane integrity, mitochondrial activity, and normal larvae rate were not different between treatments. Fertilization and hatching were higher in the post-thaw diluted sperm (93 +/- 3%; 82 +/- 9%) when compared to control samples (65 +/- 13%; 55 +/- 17%). Were used oocytes from one female, limiting these results. The post-thaw dilution improved the sperm kinetics and reproductive parameters. Thus, this methodology can be included in the sperm cryopreservation protocol for R. quelen.