| dc.description.abstract | Motility rates of sperm cells affect conception rates, which affect overall dairy production rates. Cryopreservation of cells can damage the cell’s integrity and biological functions, including motility. Fresh and thawed motility rates of bovine spermatozoa are important to consider for assisted reproductive technologies (ART) used within the dairy industry. This study was designed to develop a clarified egg yolk cryoprotective bovine semen extender using acids other than citric acid, to increase bovine spermatozoa motility for ART and reduce media debris for less interference with motility. This experiment consisted of two phases. Two basis media were created for Phase 1, Basis A and B, were comprised of industry standard components, and Basis B included 125 mM of added erythritol to act as a cryoprotectant. Treatment acid media were created from Basis A and B by using nonbiological or biological acids, with emphasis on biological acids within the Krebs cycle. Phase 1 screened 16 fresh clarified extenders with 33% homogenized egg yolk (HEY) across 5 dairy bull ejaculates to determine acids studied in Phase 2. Motility and progressive motility percentages were recorded for each treatment up to 13 days and statistically analyzed. Seven treatments advanced to Phase 2 for temperature stress tests. Phase 2 utilized fresh and cryopreserved clarified extenders with 50% raw egg yolk (REY), due to better clarification than HEY, across 11 dairy bull ejaculates. There were significant differences among the Phase 2 fresh treatments for motile (p=.004) and progressive motile percentages (p<.0001) with α-ketoglutaric acid (AKG) and citric acid, the control (CON), being similar and greater than all other treatments, except malic acid (MAL) and fumaric acid plus pyruvate (PYR). Phase 2 postfreeze data also illustrated that there were significant differences in treatment for motile (<.0001) and progressive motile percentages (<.0001), with AKG and CON being similar and possessing the highest motility than all other treatments, except MAL. CON and AKG were similar and retained the highest progressive motility percentages compared to all other treatments except for PYR. Evidence showed that the hypothesized most advantageous treatment, citric acid plus erythritol (CAMERY), was outperformed by the previously mentioned acids.' | |
