Seminal quality attributes and their interrelationships in gaddi and chegu bucks

Abstract

A study was conducted to compare the seminal quality attributes in Gaddi and Chegu goats. A total of 286 ejaculates (Gaddi -106, Chegu -180) from adult healthy post-pubertal bucks (11 Gaddi and 8 Chegu) were collected twice weekly using artificial vagina. The ejaculates were extended in tris citrate egg yolk (TEY) extender to maintain a concentration of 150x10 6 spermatozoa/straw. Randomly selected straws from each ejaculate were thawed at 37ºC for 30 sec, 24 h post incubation to compare seminal quality characters between fresh and post-thaw semen along with the changes due to processing. The results showed significantly (P<0.01) lower volume (0.66±0.04 vs 0.77±0.04 ml) with higher sperm concentration (3401.0±247.2 vs 1968.76±134.97x10 6 sperms/ml) in Gaddi as compared to Chegu bucks. Interrelationships among gross semen characters showed significant (P<0.01) correlation between sperm concentration and mass motility in Gaddi (r=0.506) and Chegu (r=0.715) bucks. Progressive motility was significantly (P<0.01/0.05) correlated with viability (r=0.326 and r=0.692) and morphological abnormalities (r=-0.393 and r=-0.257) in fresh diluted and post-thaw Gaddi semen. Likewise, in Chegu goats progressive motility was significantly (P<0.05/0.01) correlated with viability (r=0.236 and r=0.641). Morphological abnormalities were significantly (P<0.05) correlated with hypoosmotic swelling test (HOST) reactivity (r=-0.231) in fresh and with progress motility and viability (r=-0.248 and r=-0.323) in post-thaw semen in Chegu only. Significantly (P<0.01) higher progressive motile (35.18±0.87 vs 30.86± 0.78 %) and HOST reactive sperm (52.48±1.43 vs 37.57±1.19%) were observed in Gaddi than Chegu bucks. In conclusion, higher progressive motility and HOS Treactivity along with lower per cent changes in these characters due to processing in Gaddi bucks suggest better resilience of this breed to cryopreservation compared to Chegubucks.