Reactive oxygen species (ROS) are created in excess during the cryopreservation process, which speeds up the rate of lipid peroxidation (LPO). This negatively impacts spermatozoa functions and reduces their capacity to fertilize. The spermatozoon plasma membrane consists of significant amounts of polyunsaturated fatty acids (PUFA), which can be easily oxidized by ROS and produce harmful agents that are toxic to cells. The plasma membrane of rooster spermatozoa contains high concentrations of polyunsaturated fatty acids and very small amounts of mitochondria, cytoplasm, and cytoplasmic antioxidants. Cryopreservation of rooster semen has been associated with adverse effects, including increased lipid peroxidation, structural damage in the mitochondria and acrosomal area, changes in the integrity and permeability of the spermatozoon plasma membrane, and severe damage to DNA. In the study, semen taken from 20 Plymouth Rock roosters were pooled to eliminate individual differences. By adding 5 μg/mL, 10 μg/mL, 15 μg/mL, 20 μg/mL and 25 μg/mL shilajit to Beltsville Poultry Semen Extender diluent, 5 experimental and 1 control groups were formed and frozen in 0.25 mL straws. After thawing in a water bath at 37oC, spermatologic parameters were analyzed with the CASA system. Viability evaluations were made with eosin – nigrosin stain and morphological evaluations were made with Hancock method. Sperm DNA integrity was examined with the COMET assay. As a result, it was concluded that the addition of 10, 15, 20 μg/mL shilajit to rooster semen extender improves semen quality parameters and DNA integrity of semen after cryopreservation.
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