Fig. 5

Changes in canine sperm DNA fragmentation were detected by SCDT during cold storage (5 °C) in the extenders containing different levels of melatonin versus the controls. A two-way repeated-measures ANOVA statistical test was used to make a comparison between treatment groups at different times. Pairwise comparisons with LSD confidence interval adjustments were carried out to examine the simple effects for the time and study groups. The different letters in bar superscripts indicate a statistically significant difference (P ≤ 0.05) between study groups at Day 3 or 5. Negative Control (without Melatonin or DMSO), Positive Control (containing DMSO), M1 (containing 0.5 mM Melatonin), M2 (containing 1 mM Melatonin), and M3 (containing 2 mM Melatonin), ns, non-significant. All numbers are presented as Means±SEM. L = Large Halo (No DNA fragmentation), S=Small Halo (Partial DNA fragmentation), and N=No Halo (Complete DNA fragmentation), SCDT = Sperm Chromatin Dispersion Test