A research on cryopreservation of Phu Quoc dog semen

Abstract

Study on Cryopreservation for Phu Quoc dog semen was conducted in order to serve for the conservation and propagation of this breed by artificial insemination. (i) The quality of sperm of 6 Phu Quoc dogs was evaluated. The semens were harvested in 6 times per sire, the interval between each harvesting time was 5 days. The studied results showed that the volume of semen containing highest number of sperms was 1.42±0.13 ml, sperm activity reached 0.86±0.05 points, sperm concentration was 604.7 ± 85.0 million sperms per 1 ml semen, of which the total number of sperms moving directly per each harvesting time reached 496.9 ± 38.9 million spermatozoa and the sperm abnormality rate was 11.1 ± 0.9%. The semen samples were packed in straws with 0.25 ml containing a total of 100 million sperm per dose and conserved in liquid nitrogen according to the CERCA procedure (Benechet, 2007) in TCG (Tris-Citrate-Glucose) medium supplemented 20% of egg yolk, with cryo-protectants, such as: glycerol (at the test levels: 0, 4, 6 and 8% by volume) or ethylene glycol (at the test levels: 0, 6, 8 and 10% by volume). After 2 days of conservation in liquid nitrogen, the semen samples were thawed at 370C for 1 minute. The result of testing sperm quality showed that the activity of sperm after thawing reached the highest level in the medium containing 6% glycerol or 8% ethylene glycol, that was 0.46 ± 0.02 and 49 ± 0.03 points, respectively, and the sperm abnormality rate was 24.61 ± 0.39% and 22.86 ± 0.33%, respectively