Avaliação da qualidade espermática de bovino após descongelamento

Abstract

The objective of this work was to evaluate the quality of thawed semen using different techniques. Five different bulls were evaluated, 4 Nellore and 1 Charolais. The Slow thermoresistance test (TTRl) consisted of evaluating motility at time 0, 60, 120, 180 and 240 min at a temperature of 38ºC and the fast thermoresistance test (rTTR) evaluated the same aspects at a temperature of 45ºC at time 0, 15 and 30 min. Sperm morphology verified the viability of the semen after thawing and the hypoosmotic test (THO), the osmotic balance capacity of the cells. There was a greater amount of spermatozoa with bent tails and decapitated, but they remained within the morphological quality standard, as well as vigor and motility in T0. THO revealed a great variability of cells with hyposmotic regulation potential, but all samples were within the acceptable standard. There was no statistical difference in the means found in the TTRr comparing MOT and vigor between the samples, but there was a statistical difference between the means of each time used. The difference in relation to time in the TTRl found in was more significant than in the TTRr, in addition to there being a difference between the results when comparing the vigor between the samples in the TTRl. Therefore, it is concluded that semen pathology analysis together with THO are effective to assess the condition of the cell and that rTTR is the test of choice because it causes less damage and uses less time.