The effect of adding different raffinose concentrations in the diluents in semen cryopereservation of different breeds of ram at the reproductive season

Ram semen has proven to be more difficult to cryopreserve than semen of other farm animals. Cryopreservation, adversely the cryosurvive of spermatozoa, leads to reduction of sperms fertile life. The aim of this study was to investigate the effect of supplementation of diluent with different raffinose concentrations in the cryopreservation of three breeds of ram semen during reproductive season. Ejaculate samples were collected from 3Ghezel,2Ghezel-Merinos and 2Merinos-Moghani rams using artificial vagina. Samples immediately were transported to the laboratory and a primary evaluation was done at 37°C. Semen samples were diluted with a Tris-based extender complemented with 50, 75, 100 mM raffinose and an extender containing no raffinose as a control group. Semen samples were aspirated into 0.25 ml straws, cooled to 5°C and after frozen finally stored in liquid nitrogen. Achievedresultsshowed thatthe highest percentage of alive sperms belonged to 75 mMraffinose (75.47±0.83) and the lowest to control groups(70.76±0.88).The highest percentage of motilityandprogressive motility were observed in raffinose 50 mM(52.84±1.33and45.98±1.33 respectively), while the control grouphad the lowest percentage of motile sperm andprogressive motility (41.18±1.38 and 35.41±1.38 respectively). Percentage of abnormal sperm in100 and 75 mM Mraffinose (8.58±0.32 and 8.93±0.31) was thelowest andthe control group (9.78±0.32) had the highest percentage of abnormal sperm (P<0.05). This study showed that raffinose improved cryopreservation of ram semen. Also the highest percentage of alive sperms, motility and progressive motility were observed in the Ghezel rams and the lowest percentage of abnormal sperm recorded in Ghezel-merinos rams. This study showed that raffinose improved cryopreservation of ram semen. Also preservation capacity of Ghezel rams were better than the other breeds.