Diluent Containing Dimethylformamide Added With Sucrose Improves In Vitro Quality After Freezing/Thawing Stallion Sperm.
Authors: Moura Thalles C M, Arruda Lúcia C P, Araújo Silva Robespierre A J, Silva Raquel P F, Oliveira Aline S, Tobal Lucas F M, Batista André M, Carneiro Gustavo F, Guerra Maria M P
Journal: Journal of equine veterinary science
Summary
# Editorial Summary Cryopreservation of stallion semen remains a cornerstone of equine reproductive management, yet post-thaw sperm viability frequently falls short of fresh semen standards. Moura and colleagues investigated whether supplementing a dimethylformamide-based freezing extender with sucrose could enhance semen survival through the freeze-thaw cycle, collecting samples from six stallions and cryopreserving them in media containing 0, 25, 50, or 100 mM sucrose alongside a commercial control. The addition of 50–100 mM sucrose significantly improved progressive and total motility alongside velocity parameters (VCL, VSL, VAP) compared to unsupplemented controls, whilst all sucrose concentrations elevated amplitude of lateral head displacement and beat cross frequency beyond the commercial extender. Most notably, 100 mM sucrose resulted in superior preservation of both plasma and acrosomal membrane integrity alongside robust mitochondrial membrane potential—critical markers of sperm function and fertilisation capacity. These findings suggest that practitioners utilising custom freezing protocols could substantially improve post-thaw semen quality by incorporating 100 mM sucrose, potentially enhancing conception rates in cooled-semen breeding programmes, though validation across larger stallion populations and field fertility data would strengthen the clinical recommendation.
Read the full abstract on PubMed
Practical Takeaways
- •Addition of 100 mM sucrose to dimethylformamide-based freezing media can improve post-thaw stallion semen quality, potentially enhancing fertility outcomes in artificial insemination programs
- •This approach may offer a cost-effective modification to standard freezing protocols by improving sperm survival and function without requiring expensive commercial alternatives
- •Practitioners using frozen stallion semen for breeding should consider whether their extender includes sucrose supplementation, as it demonstrably preserves motility and membrane integrity critical for fertilization
Key Findings
- •Addition of 50-100 mM sucrose to freezing extender increased total motility, progressive motility, and velocity parameters (VCL, VSL, VAP) compared to control
- •100 mM sucrose significantly improved percentages of sperm with intact plasma and acrosomal membranes and high mitochondrial membrane potential after thawing
- •Sucrose-supplemented groups (25, 50, 100 mM) showed higher ALH and BCF values compared to commercial BotuCrio extender