EFFECTS OF STORAGE TIME ON THE MOTILITY, MORTALITY, AND CALCIUM LEVELS OF ATLANTIC SALMON SALMO SALAR SPERMATOZOA.

^{1*J. Parodi, 1 G. Guerra 3M. Cuevas, 2A. Ramírez-Reveco & 3F. Romero}

^{1Laboratorio de biología celular aplicada, Nucleo de investigacion en produccion alimentaria, Escuela de medicina veterinaria, Facultad de recursos naturales, Universidad Católica of Temuco, Chile}
^{2Cryobiology and Spermatozoa Functionality Analysis Laboratory. Institute of Animal Sciences, Faculty of Veterinary Sciences, Universidad Austral de Chile, Valdivia, Chile.}
^{3Center of Neurosciences and Peptide Biology, Faculty of Medicine, Universidad de La Frontera, Temuco, Chile}

^{Jorge Parodi}
^{Av. Las Mariposas S/N}
^{Campus Dr. Rivas}
^{Universidad Catolica de Temuco}
^Temuco
^Chile
^{jparodi@uct.cl}

Abstract

This study estimates spermatozoa mortality, morphology, motility, and intracellular calcium levels in Atlantic salmon Salmo salar L. 1758 milt after a prolonged storage period. Milt samples were preserved at 4°C for 25 days and then evaluated for mortality. Spermatozoa motility was determined using the ImageJ-CASA program: calcium content was measured by loading spermatozoa with a calcium fluorescent probe, followed by confocal microscopy and microfluorimetry. Reduced spermatozoa mortality was observed before 5 days of storage. Motility remained high for the first three days. A decrease of more than 50% in calcium content was observed after 5 days of storage. When spermatozoa were activated, calcium levels increased by over 200% in relative fluorescence units (RFU); this rate of increase was lost when the samples were stored for extended periods of time, and was only partially manifested in a zero calcium solution.

The results suggest that in vitro storage of S. salar spermatozoa at 4°C for a period of three days preserves mortality and motility at levels similar to those of fresh spermatozoa. This method also maintains intracellular calcium storage critical for spermatozoa performance.

Keywords

Milt; conservation; viability; function