The aim of this study was to determine the effect of two equilibration temperatures (5 °C and room temperature) and two cryoprotectants (glycerol and dimethylformamide, both at 7%) on llama sperm cryopreservation. Llama ejaculates were divided into four aliquots. A lactose-EDTA-egg yolk (LEEY) extender with either 7% glycerol (LEEY-G) or 7% dimethylformamide (LEEY-DMF) was added to two of the aliquots, which were equilibrated for 20 min at room temperature and subsequently frozen. The other two aliquots were extended in LEEY, cooled to 5 °C, then LEEY-G or LEEY-DMF was added, equilibrated for 20 min at 5 °C and frozen. No significant differences (P > 0.05) were observed in membrane function and chromatin condensation between any of the freeze-thawing protocols. Post-thaw motility was greater (P < 0.05) in LEEY-DMF than LEEY-G. DNA fragmentation was not different between raw and frozen semen with LEEY-DMF but was high in all samples with glycerol. Our results indicate that 7% glycerol would be detrimental for llama spermatozoa, but further studies are needed to evaluate effectiveness if used at lower concentrations. Dimethylformamide preserved motility and DNA integrity of frozen-thawed llama spermatozoa and could be used to replace glycerol at the concentrations used in this study.

In South American camelids, sperm survival is low after thawing and poor results are obtained when artificial insemination is performed with cryopreserved semen. The aim of this study was to evaluate the effect of different percentages (10% and 50%) of seminal plasma added prior to the process of cryopreservation and also to evaluate the absence of seminal plasma on llama sperm survival after freezing and thawing. A total of 15 ejaculates from five adult llama males (n = 5; r = 3) were evaluated. A significant decrease in sperm motility, viability, membrane function and intact acrosomes was observed in thawed samples (0%, 10% and 50%) when compared to raw semen. Neither morphology nor chromatin condensation was altered in all thawed samples (p > 0.05), but a significant increase (p < 0.05) in the percentage of spermatozoa with fragmented DNA was observed after thawing all samples compared to raw semen. Higher percentages of total and progressive sperm motility were observed when 0% and 10% of seminal plasma were used compared to 50%. However, no statistical differences were established for sperm viability, membrane function, morphology, acrosome status and DNA quality between thawed treatments. To conclude, neither of the percentages of seminal plasma used showed superiority nor cryoprotective effect on llama sperm survival.

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