title: The effect of zwitterion buffers on the freezability of Boer goat semen.
abstract: Twenty semen samples with mass activity greater than +3 were collected from six healthy, mature Boer goat bucks. Each ejaculate was divided into four equal parts and extended at 37 degrees C in Tris, Test, Tes and Bes buffers containing egg yolk and glycerol. Semen was placed into medium size French strawsand after 2 hours of equilibration at 5 degrees C, frozen in the vapour phase and stored in liquid nitrogen for 7 days at -196 degrees C. Progressive motility, the number of live spermatozoa and glutamic oxaloacetic transaminase (GOT) release were studied after the initial extension, after equilibration and after 15 minutes and 7 days of freezing of semen. Semen samples when extended with Tris yolk glycerol showed significantly (P<0.01) higher progressive motility and live spermatozoa than when extended with the other zwitterion buffer-based extenders. The change of extenders did not influence the release of GOT at various stages of freezing of semen (P>0.05).
authors.affiliation: Institute of Animal Husbandry and Genetics University of Gottingen, Albrecht-Thaer-weg3 D-3400, Gottingen, Germany.
authors.forename: R K
authors.initials: RK
authors.lastname: Tuli
authors.forename: W
authors.initials: W
authors.lastname: Holtz