Discipline: Veterinary Medicine
The microscopic characteristics of chilled and frozen-thawed canine semen were determined and compared. Semen samples were collected from 8 apparently healthy nondescript native and 4 purebred adult male dogs by means of digital manipulation. After collection the sperm-rich fraction was diluted with a Tris-raffinose-glycerol extender, equilibrated to and stored at 5 C for four hours. After equilibration for four hours. The aliquot was divided into 2, one aliquot was cryopreserved by freezing for 7 days while the second aliquot was stored from another 4 hours at 5 C. The chilled semen's microscopic characteristics such as sperm motility sperm morphology, and dead-alive ratio were examined after four and eight hours while those of the frozen semen were assessed after thawing. No significant differences had been observed between semen chilled for four and eight hours with fresh undiluted semen ill terms of percentage live and abnormal sperm cells as well as motility, which is 50 to 70 percent (grade 3). However, frozen semen stored for seven days resulted to a decrease in live (40.83%) and normal sperm cells (26.33%) registering a significant decrease in motility of 30 to 50 percent (grade 2) compared to fresh undiluted semen and semen chilled for four and eight hours. Results obtained from the study suggest that extended semen dulled for up to 8 hours had similar characteristics as that of fresh undiluted semen with respect to monthly and dead-alive ratio. However, Frozen-thawed semen showed a reduction in said characteristics.