Mink semen studies: i. liquid preservation and prospect of freezing spermatozoa

Abstract

Using 22 males, 41 semen samples were collected from the vagina of mink by means of a plastic tubing attached to a 1 ml syringe. Subsamples of vaginal semen were diluted in 4 different extenders, viz., tris (tris, citric acid, glycine, fructose, glycerol and egg yolk), PVP (tris extender with polyvinyl pyrrolidone and caproic acid), milk (boiled and filtered milk with glycerol) and sodium citrate. The extended semen samples were stored at 23, 5 and -196° C for varying periods and evaluated for % motile spermatozoa. In the tris extender storage for 3 days at 5° C or for 2 days at 23° C reduced the number of spermatozoa by more than 50%. When milk was used as the extender, the motility decreased from an initial value of 68% to 10% after 5 days of 5° C and to 8% after 4 days at 23° C. The PVP extender was not suitable for storage at any temperature. After being frozen at -196° C for 2 hr, the motility ranged from 3-10% in the tris extender and was zero in milk and PVP extenders. Prolonged storage for 7 days in tris extender reduced the motility to 1-7%.