Preservation and evaluation of Jamunapari buck semen and it’s fertility after artificial insemination in goats

Abstract

Preservation of buck semen is necessary for rapid improvement in goat production. The goals of this study were to evaluate the quality of fresh semen from Jamunapari bucks, the effects of different semen extenders on the quality of preserved semen, and the fertility of goats using preserved semen after AI. Semen was collected from two adult Jamunapari bucks once a week using the Artificial Vagina (AV) method. Fresh semen from the two JP bucks was evaluated immediately after collection for quality assessment, such as volume, color, density, concentration, mass motility, pH, morphology of sperm, and functional integrity. Fresh semen from two bucks was pooled in a sterile falcon tube and processed for chilling and cryopreservation with Tris-citrate egg yolk (2.5% and 5% EY) and skimmed milk-based (SD) extenders. The effects of these extenders on preserved semen quality and fertility after AI in goats were observed. Fresh semen quality, volume (1.33±0.10 vs 1.06±0.15 ml), concentration of spermatozoa (3166.34±22.31 vs 2908.42±41.03×106/ml), sperm viability (85.06±0.21 vs 82.73±.73 %), normal sperm (94.73±0.20 vs 93.91±0.29 %) and HOST +ve sperm (82.53±0.18 vs 80.10±0.47 %) found different in between bucks (p<0.05). In chill semen preservation, 5% TCEYc extenders maintained better semen quality than 2.5% TCEYc and SDc extenders from day 1 to day 4 of storage (p<0.05). Moreover, semen quality decreased dramatically during storage at 4 °C (p<0.001). Similar to chilled semen, in frozen semen, 5 % TCEYf also maintained higher motility, viability, functional integrity, and normal morphology of spermatozoa compared with 2.5 % TCEYf and SDf, respectively, with different cryopreservation times: days 1, 5, 10 and 20th day of observation (p<0.001 for all). However, the preservation time did not affect semen quality for each extender during cryopreservation (p > 0.05). Cervical AI was performed in natural estrous goats using chilled semen, and no significant effect of extenders on PR was found (p > 0.05), with an overall PR of 49.12%. However, PR was significantly higher when CAI was performed with frozen semen extended with 5% TCEYf (46.42%) than with 2.5% TCEYf (32.14%) and SDf (26.92%) (p<0.05). The overall PR in goats using JP buck frozen semen extended with these three extenders was 35.36 %.