Effect of Sericin Supplement in Tris-egg Yolk Citrate Extender on Quality of Cryopreserved Semen from Thai Native Bulls

Abstract

We investigated the effect of different concentrations of sericin supplement in Tris-egg yolk extender on the post-thawed Thai native bull semen quality. Semen collected by electro-ejaculator once a week for four consecutive weeks from four Thai native bulls were divided into four aliquot and diluted with Tris-egg yolk extender containing 0% (control), 0.1%, 0.5%, and 1.0% sericin and frozen. Thawed
semen samples were evaluated for sperm motions characteristics, sperm viability, plasma membrane and acrosomal integrity, and lipid peroxidation. Significant differences (p < .05) were observed in total motility, progressive motility, VAP, and VCL with 0.1% and 0.5% sericin showing the highest values for these motion parameters. Similarly, there was significant difference in the percentage of
HOS reactive spermatozoa among the treatments (p < .05) with the highest HOS reactive sperms in semen cryopreserved in extender containing 1.0% followed by 0.5% sericin, and the lowest in 0% sericin. Further, 0.1% sericin showed significantly higher percentage of viable spermatozoa than the rest of the treatments. Additionally, the lipid peroxidation tended to decrease with increasing concentration of sercin in the extender. Sericin supplement in Tris-egg yolk extender has beneficial effect on the post-thaw sperm motility and viability. Supplement of sericin at 0.1% and 0.5% in extenders improved semen cryopreservation and quality.