Crio- preservación y viabilidad espermática de semen de bovinos charolais post-descongelación con diferentes concentraciones de trehalosa.

Abstract

This investigation was carried out to evaluate the sperm viability of fresh and thawed semen from Charolais cattle with different concentrations of Trehalose. It was developed in the Bovine Reproductive Biotechnology Laboratory of the Provincial Autonomous Decentralized Government of Morona Santiago, and a second thaw in the Biotechnology of Animal Reproduction in the School of Animal Sciences Laboratory of the Higher Polytechnic School of Chimborazo. With a breeder of the Charolais race, which was extracted eight ejaculates with artificial vagina, with a collection interval of 4 days, the duration of the investigation was 60 days. A completely randomized design was used, analyzing only the effect of Trehalose. For the (T25) 25 mEq/liter solution was used, for the (T50) 50 mEq/liter solution and a control treatment (T0) commercial diluent. Resulting in fresh semen were: very good color, sweet smell like fresh milk, very good appearance, volume of ejaculate of 6,24 ml ± 0,36. Mass motility (points) 2,75 ± 0,16. pH 6,88 ± 0,08. Individual motility (%) 70,38 ± 4,26. Live cells (%) 88,97 ± 1,72. Dead cells (%) 11,03 ± 1,72. Normal sperm (%) 79,03 ± 0,55, and a sperm concentration 650,00 ml 106 ± 5,81. For diluted semen an initial motility 0 hours (points) was obtained in (T0) 4,67 ± 0,62; (T25) 3,67 ± 0,62 and (T50) 0,67 ± 0,62. Living cells (%) (T0) 90,67 ± 4,97 followed by (T25) 78,92 ± 4,97 and (T50) 57,33 ± 4,97. Dead cells (%) (T0) 9.33 ± 4,97; (T25) 21,08 ± 4,97; (T50) 42,67 ± 4,97. Normal sperm (%) (T0) 91,83 ± 1,16; (T25) 87,92 ± 1,16; (T50) 83,92 ± 1,16. Sperm concentration (0,5 ml 106) (T0) 32,33 ± 2,78; (T25) 31,33 ± 2,78; (T50) 32,16 ± 2,78 and for thawed semen the initial motility was reached 0 hours (%) in the (T0) 3,88 ± 0,31; (T25) 2,50 ± 0,23 and (T50) 0,31 ± 0,23. Living cells (%) (T0) 65,16 ± 1,73; (T25) 56,27 ± 1,73 and (T50) 38,16 ± 1,73. Dead cells (%) (T0) 34,84 ± 1,73; (T25) 43,73 ± 1,73; (T50) 61,84 ± 1,73. Normal sperm (%) (T0) 90,58 ± 0,76; (T25) 85,00 ± 0,76; (T50) 79,11 ± 0,76. Sperm concentration (0.5 ml 106) (T0) 33,34 ± 2,94; (T25) 32,84 ± 2,94 (T50) 32,96 ± 2,94. It was concluded that the sperm viability in fresh and thawed semen in the investigation obtained the best result with (T0) followed by (T25) and finally (T50) which can be used in artificial insemination. We recommend guiding the research to post-thawing to obtain semen of better quality in cattle and avoid the failure in the pregnancy of the cows, and in turn, avoid the loss of genetic material significant in genetic improvement.