Selected qualitative and biochemical parameters of cryopreserved semen of Holstein-Friesian (HF) AI bulls.

Selected qualitative and biochemical parameters were determined in cryopreserved semen used for artificial insemination, sampled from 120 bulls reared at the Animal Breeding and Insemination Center in Bydgoszcz. The total average motility of the analyzed sperm samples was determined at 62.51%. The percentage of motile spermatozoa displaying progressive forward motility was 21.65%. Analyzed samples were characterized by a high percentage of sperm cells with a intact plasma membrane (71.21%) and active mitochondria (71.32%). High efficiency of the enzymatic antioxidant system of the evaluated sperm cells was demonstrated by high activity of CAT, GPx and SOD (494.37, 2847.83 and 5.31U/1x10(9) spermatozoa, respectively) values and low values of the DNA Fragmentation Index (9.32). The results of the study, obtained with the involvement of advanced analytical methods, indicate a high fertilizing capability of the analyzed sperm samples.