تاثیر سطوح مختلف گلیسرول بر ویژگیهای منی قوچ دالاق در شرایط قبل و پس از انجماد

The objective of this study was to investigate the effect of different levels of glycerol on Dallagh rams semen characteristics in pre and post freezing conditions. Semen samples were collected from 4 healthy and mature rams using an electro ejaculator, were mixed with Tris extender in a ratio of 1:4 semen and assessed at 5°c. 0.5 ml of straws were filled with diluted semen and kept above liquid nitrogen vapor within 7 minutes and after 10 days were thawed to investigate live and motility percentage of spermatozoa and morphological characteristics. The experiment was carried out on the basis of completely randomized design with 3 treatments including 3 levels of glycerol (4, 6, 8%) and 9 replicates. Results showed that the effect of glycerol on live and motility percentage of pre and post freezing spermatozoa was significant (P<0.05), but had not significant effect on morphological characteristics of spermatozoa (P>0.05). The highest survival and motility percentage and the lowest morphological defects of spermatozoa were obtained in 4% glycerol. Therefore using 4% glycerol in Tris extender is recommend for semen storage of Dallagh rams in pre and post freezing conditions.