The aim of this study was to evaluate the effect of increasing the concentration of protein of the seminal plasma in the extender used for frozing equine semen. Three treatments were compared: The conventional one, defined by using only the Botu-Crio® extender for frozing semen; and other two defined by adding 10% (v/v) or 20% (v/v) of seminal plasma proteins to Botu-Crio® extender. Averages of total and progressive motility were statistically higher in the conventional treatment than in that defined by adding 20% (v/v) of seminal plasma proteins but they did not differ from those obtained by adding 10% (v/v) of seminal plasma proteins to Botu-Crio® extender. The best results for the hypoosmotic test and the number of live spermatozoa were obtained in the conventional treatment, and results for adding 10% (v/v) of seminal plasma proteins were better than those obtained by adding 20% (v/v) of seminal plasma proteins to Botu-Crio® extender. These results indicate that the addition of concentrated protein of the seminal plasma to the extender did not improve the cryopreservation of equine semen.
cryopreservation; equine; semen; seminal plasma
