Protein quantification in frozen swine semen filtered with Percoll

In this study, the protein concentration in fresh and frozen semen samples from three breeds was determined using discontinuous Percoll gradients. Ejaculates (n = 34) from Large White, German Pietrain, and Duroc-Jersey boars were cryopreserved. After thawing, Percoll gradients were used to process the samples. Protein extraction was performed through the Bradford method. The absorbance of the solution was measured using a microplate spectrophotometer at 562 nm and aliquots were analyzed after solvation. Protein concentration were evaluated using the absorbance values of the lowest dilution within the calibration range. Protein concentration was higher in fresh samples (0,169 mg/ml) compared to frozen samples (0,127 mg/ml). Among breeds, Duroc samples showed the highest protein concentration (0,163 mg/mL), followed by Large White (0,146 mg/mL), and German Pietrain (0,129 mg/mL). Therefore, it was shown that cryopreservation caused a decrease in protein concentration.