Discipline: Veterinary Medicine
Three factorial experiments were conducted to study the motility, livability and fertility of cock spermatozoa as affected by day of collection, dilution and cryopreservation. Diluent influenced significantly the sperm motility and livability of Philippine native chicken semen. Sperm motility of fresh undiluted semen (81.7%) was highest (P<0.05), followed by that of semen diluted with LFSE (71.2%), and then by those diluted with LFSE containing either 4.5% DMSO (53.8%) or 4.5% DMA (51.2%). Livability of fresh undiluted semen (85.4%) was higher (P<0.05) than that of diluted semen (73.3%), and the lowest were those of diluted semen with either DMSO (56.1%) or DMA (54.6%). The results demonstrated the deleterious effects of diluents and cryoprotectants on motility and livability of rooster spermatozoa.
Freezing significantly depressed cock sperm motility and livability. Motility (52.5%) of fresh semen diluted with LFSE with either 4.5% DMSO or 4.5% DMA was (P<0.05) higher compared to that of frozen-thawed semen (18.5%). Livability of fresh extended semen (55.34%) was also higher (P<0.05) than that of frozen-thawed semen (11.1 %). Likewise, freezing significantly reduced the fertilizing capacity of spermatozoa. Fertility of fresh extended semen (76.3%) was significantly (P<0.01) higher than that of frozen-thawed semen with either DMSO (1.4%) or DMA (0.8%) as cryoprotectant. Despite low fertilizing capacity of frozen semen, the study demonstrated the possibility of conserving Philippine native chicken genetic materials through cryopreservation.