Comparison between glycerol and dimethylformamide in the cryopreservation of llama semen (Lama glama)

Champí F.S.; Ampuero E.; Ordóñez C.; Meza A.; Cucho H. · Revista Veterinaria (2025) · DOI: 10.30972/vet.3628608

Resumen

The objective of this study was to evaluate the effect of two concentrations of glycerol (5% and 7%) and dimethylformamide (DMF; 7% and 9%) on the successful cryopreservation of llama semen collected by electroejaculation (EE). Sixteen ejaculates were obtained from eight adult males (4-7 years old). Semen samples were incubated with papain for 20 min to reduce viscosity, and the enzymatic action was subsequently inhibited before fresh evaluation. Samples were diluted in a Tris-based medium and gradually cooled to 5 °C over 2.5 h. They were then divided into four aliquots for cryoprotectant addition, evaluated during the cooling phase, packaged in straws, frozen within 25 min, and stored for 7 days prior to thawing. Sperm analysis was performed using a CASA-Mot system (ISAS®), assessing total motility (TM), kinematic parameters, sperm viability, and acrosomal integrity in fresh (papain-incubated), cooled, and thawed samples. Data was analyzed using a randomized complete block design, with mean comparisons performed by Tukey's test (p<0.05). Results showed that TM, viability, and acrosomal integrity were significantly higher (p<0.05) in fresh semen compared to samples treated with glycerol or DMF during the cooling and post-thaw stages. Moreover, curvilinear velocity and amplitude of lateral head displacement were higher in fresh semen and in samples treated with 5% and 7% glycerol during cooling. In conclusion, none of the evaluated concentrations of glycerol or DMF effectively preserved sperm parameters after cryopreservation. © (2024), (Universidad Nacional de Nordeste (UNNE)). All Rights Reserved.

Instituciones: Universidad Nacional de San Antonio Abad del Cusco