Study of the freezability of post-mortem sperm samples of Iberian deer. Variation sources

The development of techniques that allow in an effective way the criopreservation of deer semen is an objective of great so much interest from a point of view conservationist as productive. Thus, the objective of this thesis have been studied that characteristics of seminal quality are relationship with the cryoresistance of the sperm samples. Also, we have evaluated which intrinsic factors to the male (age, genetic variability, the body condition, and stress degree) have influence on the resistance to the freezing as well as, the best time of the year for freezing the sperm samples.;The results showed that the parameters evaluated initially that were related positively with the cryoresistance were: the concentration, the total number of spermatozoa, the percentage of motility spermatozoa, the quality of the movement and the percentage of spermatozoa with droplet distal citoplasmatic, while the relationship with the spermatozoa with droplet proximal citoplasmatic was negative. In the other hand, a negative relationship was showed among the percentage reacted acrosomes at 5 and 10 minutes after incubation with a calcium ionophore and the cryoresistance. In the opposite, a positive relationship was obtained among the resistance for the motility at 60 and 120 minutes after a thermal test and the cryoresistance. All these relationships were not very strong.;Likewise, the influence of the month in which the testes were obtained was evaluated. In the months of November and December the cryoresistance was higher than in October, January and February among which were not significant differences.;The intrinsic parameters evaluated were the age (by means the cement lines in the tooth), the genetic variability (by means of the molecular markers as microsatellites), the body condition (by means of the index kind fat) and the stress degree (by means of the weight adrenal glands). In what concerns to the intrinsic parameters, the age did not any influence on the cryoresistance. However, the genetic variability, the body condition and the stress degree were relationship with the cryoresistance. These relationships were negatives in all the cases.