Abstract

This study aimed to compare the efficiency of four cryodiluents on post-thawing activity of Arabian stallion spermatozoa. Semen samples were collected from 10 Arabian stallions, diluted with modified INRA-82 (m-INRA), modified Kenney’s (m-Kenney) and or Eqi-Pro® diluents and subjected to cryopreservation. Post-thaw motility, membrane, acrosomal and mitochondrial integrities were evaluated. The results revealed the superiority of m-INRA over m-Kenney and or Eqi-Pro® in terms of post-thaw motility (52.50 ± 2.27 vs. 43.00 ± 2.13 and 41.50 ± 2.59%, respectively), viability index (134.25 ± 5.99 vs. 97.50 ± 6.40 and 94.75 ± 7.33, respectively), sperm membrane (46.60 ± 2.05 vs. 36.70 ± 1.73 and 36.60 ± 2.09%, respectively) and acrosome integrities (54.50 ± 1.30 vs. 43.00 ± 1.86 and 43.5 ±1.86%). Activities of stallion sperm mitochondria were better preserved using m-INRA as cryodiluent. Using Kenney’s extender resulted in the lowest sperm motility and integrities of acrosome and membranes (33.00 ± 2.13, 35.50 ± 1.38 and 29.80 ± 1.14%, respectively). In conclusion, the motility as well as functional integrities of Arabian stallion spermatozoa could be enhanced using m-INRA as a cryodiluent.

Key words: Stallion-semen-cryopreservation-diluent-INRA-Kenny’s- Eqi-Pro