Seleção espermática em três espécies de cervos: Mazama americana (Erxleben, 1777), Mazama gouazoubira (Fischer, 1814) e Mazama nemorivaga (Cuvier, 1817)

Abstract

This study aimed to select high quality sperm, through sperm separation by density gradient centrifugation (DGC) and by magnetic activation cell separation (MACS), in fresh semen from deer of the genus Mazama. Semen from six deer was collected using the electroejaculation technique after chemical restraint. The following analyzes were performed: motility and vigor, morphology (smear stained with Congo red) and supravital test (eosin-nigrosin), in addition to DGC and MACS. For DGC, Percoll® was used with 20 x 106 cells in a 400 μl gradient of Percoll® at 90% and 45%. In MACS, 10 x 106 cells were used with the pellet resuspended in 150 μl of HEPES with 20 μl of nanoparticles linked to annexin V, incubation for 15 minutes and filtration in the MiniMACS magnetic separation column, and the filtered non-apoptotic portion was collected for analysis. The results obtained for motility were 75 ± 7.1%, 71.7 ± 10.8% and 8.3 ± 4.1% in fresh semen, post DGC and post MACS, respectively. For vigor, the values obtained were 2.8 ± 0.4% for fresh semen, 2.5 ± 0.4% after DGC and 0.7 ± 0% after MACS. Total defects reduced after the selection techniques used (44.5 ± 19.6% in fresh semen, 27.3 ± 18.0 after DGC and 24.8 ± 16.4 after MACS). The individual defects that had the greatest reduction after the selection techniques were curled tail (15.5% in fresh semen, 6.2% post DGC and 4.8 post MACS) and curled tail (7.3% in fresh semen, 1 .4 post DGC and 2.0 post MACS). There was also a reduction in the number of cells with damaged plasma membrane in both techniques, and, in relation to fresh, MACS reduced by 25% and DGC by 9%. The findings suggest that these sperm separation techniques are efficient in producing high quality semen samples in deer.