COOLING CURVES OF THE BOAR SEMEN DILUTED IN ACP®103 EXTENDER ADDED OF POWDERED EGG YOLK IN FIXED CONCENTRATION

Abstract The conservation of boar semen at lower temperatures might contribute to the further expansion of artificial insemination in this species. Egg yolk cryoprotectant properties have already been extensively tested on sperm cryopreservation of several species. This study aimed to test different temperature curves for the conservation of boar semen diluted with coconut milk powdered (ACP®-103) add 7% egg yolk and to verify which one better maintains sperm viability. For this, 36 ejaculates were diluted and stored at 17, 10 and 5 °C. Daily analysis of vigor and motility were performed, and on days D0, D2, and D4 semen was evaluated regarding vitality, morphology, and osmotic resistance. For the statistical analysis we performed the tests of Kruska-Wallis with Dunns post-test (nonparametric data) and ANOVA and Tukey test (parametric data). The storage temperature of 10 °C was the best one to maintain spermatic motility at appropriate levels to be used in an artificial insemination program. Analyses of viability, morphology, and hypoosmotic test did not show statistical difference among the treatments. In conclusion, the best temperature curve was 10 °C with diluted semen previously kept at 17 °C to maintain the viability of sperm cells in pigs for a longer period.