COMPARISON OF 2 POITOU JACKASS SPERM FREE ZING METHODS AND OPTIMIZATION OF GLYCEROL CONCENTRATION

The <<Baudet du Poitou>> is a jackass domestic population threatened w ith extinction. At the present time, the global population does not ex ceed 180 individuals in the world. This emergency has necessitated fre ezing semen for preserving the genes and for establishing a sperm bank . Unfortunately, in this breed, non spermatozoa cryopreservation techn ique has been described. The aim of this study is to compare 2 freeze- thaw techniques. The first one is based on stallion freeze-thaw semen defined by INRA (protocol 1), the second is based in a prelimanary stu dy realised in Veterinary School of Nantes (protocol 2). Then, an opti misation of glycerol concentration has been realised. Semen evaluation has been done with computer analysis system. Results showed an effici ency of protocol 2 compared to protocol 1 and an optimum glycerol conc entration of 4 p. cent (v/v).