Use of chelating agent for optimum post thaw quality of buck semen

Ejaculates (35) from adult Sirohi bucks (2-4 years old) were utilized for the present study to find out the freezability of buck semen at different levels of chelating agent used (ethylene diamine tetra acetic acid - EDTA: 0, 0.01, 0.05 and 0.1%) by conventional method of freezing. The ejaculates were collected twice at weekly intervals using artificial vagina and were extended to maintain sperms concentration approximately 100 million / dose (0.25 ml) with tris- citric acid- fructose (TCF) diluent having 10% (v/v) egg yolk and 6% (v/v) glycerol as cryo protecting agent. Filling and sealing of straws were done at 5°C in cold handing cabinet after 4 h of equilibration period then straws were vapor frozen for 10 min above 2 cm of liquid nitrogen and finally put in to liquid nitrogen. Post thaw motility, live sperm count, abnormalities, acrosomal integrity and hypo osmotic swelling test had been conducted to know freezability. Analysis of data using SPSS 16 revealed that post thaw motility, live sperm count, abnormalities, acrosomal integrity and hypo osmotic swelling positive spermatozoa differed significantly at different levels of EDTA. The post thaw motility, live sperm count, acrosomal integrity and hypo osmotic swelling positive spermatozoa were significantly highest in 0.1% of EDTA used in the present study. So, 0.01% EDTA can be used as an additive in semen dilutor in routine freezing process for better post thaw recovery of buck semen.