The characterisation and cryopreservation of Venda chicken semen

ObjectiveTo characterize Venda cocks semen, find a suitable short-term diluted semen storage temperature, find a suitable cryopreservation cryoprotectant and to investigate cryoprotectant toxicity.MethodsSemen was collected from six Venda cocks and evaluated macroscopically for semen volume, pH and sperm concentration. Microscopic sperm characteristics examined included were total motility (rapid, medium and slow) progressive and non-progressive motility. Velocity characteristics included curvilinear and straight-line velocity, average path velocity, linearity, straightness, wobble, amplitude of lateral head displacement and beat cross frequency.ResultsResults showed that the average semen volume was 0.3 ± 0.1 mL, the pH 6.9 ± 0.4 and the sperm concentration (6.8 ± 79.8) × 109/mL. A positive correlation was observed between body weight and semen volume (r = 0.38). Similarly a significant difference between the initial sperm total motility (TM%) of 87.5 ± 8.6 and samples stored for 24 h at 5 °C (55.0 ± 8.0) and 25 °C (30.6 ± 6.1) was recorded. The percentage live and normal sperm was 87.0% and 93.5% (P < 0.05) respectively. The TM% recorded was significantly different in samples supplemented with DMSO (46.0 ± 8.3), ethylene glycol (EG) (45.0 ± 12.2) and propanediol (PND) (21.8 ± 10.4), following thawing. Detailed velocity values showed consistent differences between the raw and cryoprotectant-free semen samples.ConclusionsIn conclusion, the Venda cock semen was subsequently found to have a higher TM% when stored in vitro at 5 °C. DMSO and EG were found to be suitable for the cryopreservation of Venda cock semen.