Effect of different concentrations of Trolox ® in association with docosahexaenoic acid on equine semen freezing

The aim of this study was to evaluate the association of different concentrations of Trolox and the addition of a fixed concentration of DHA in the freezing of semen of Mangalarga Marchador stallions. To that end, 16 ejaculates were frozen in the following extenders: E1) BotuCrio (BC; Control); E2) BC + 50 ngml DHA + 30 µM Trolox (BCDHA30T); E3) BC + 50 ngml DHA + 40 µM Trolox (BCDHA40T); E4) BC + 50 ngml DHA + 50 µM Trolox (BCDHA50T). All the tested extenders were similar in preserving different kinematic parameters, cell functional integrity, compacted DNA, and high and intermediate mitochondrial activity (P>0.05). However, sperm cryopreserved in BCDHA40T showed higher velocities than sperm frozen in the control extender (P