Field and in vitro assay of three methods for freezing ram semen.

摘要: Glycerol has been the most widely used cryopreservation agent for spermatozoa and a wide range of factors affect its action on sperm viability fertilizing capacity. We tested three methods freezing ram semen packed in 0.25 ml straws (final cellular concentration: 100 x 10(6) spz/ml). Method M1: Two-thirds final volume diluent was added as solution A (without glycerol) to pure at 35 degrees C. The sample cooled 5 C (-0.30 C/min), one-third B concentration glycerol 4%) maintained 2h. It then frozen programmable biofreezer (-20 C/min down -100 C). M2: diluted with specific 3%), (-0.20 C/min) left After that, it nitrogen vapours. M3: Semen 1:1 (concentration 2%) (-0.25 C/min). again same 4%). 1h Best total motility (TM) progressive (PM) (75.8 55.18%) were obtained using M3. Methods M1 M3 gave significantly higher values (P<0.05) kinetic parameters: average path velocity (VAP) (81.3 85.2 microm/s), straight-line (VSL) (72.8 77.3 microm/s) linearity (LIN) (66.6 68.8%). M2 showed lowest parameters (VAP 74.4, VSL 67.3 LIN 62.5) highest percentage cells damaged plasma membrane (53.8%). worst results acrosome status assessed fluorescence probes (31.3%-dead acrosomes-versus 25.4% 23.3% M3). field trial carried out fertility pregnant or lambing ewes (67.3% versus 51.1% 58.8% M2). concluded that use simple dilution medium (test-fructose-glycerol-egg yolk) addition (to 2% 4% C) two steps together productive method semen.