Abstract
The present study aimed to investigate the effect of different concentrations of sodium dodecyl sulfate (SDS), egg yolk and glycerol on the freezability and DNA integrity of stallion spermatozoa. Semen samples were collected from 7 Arabian stallions, centrifuged, extended in INRA-82 supplemented with different concentrations of SDS (0.00, 0.01, 0.02, 0.03 and 0.04%), egg yolk (5, 10, 15 and 20%) and glycerol (3, 4, 5, 6 and 7%), and processesed for cryopreservation. Post-thaw motility, acrosome and membrane integrity of spermatozoa were assessed and comet assay were applied to determine DNA integrity of spermatozoa. Results showed that the addition of appropriate concentration of SDS is fundamental for equine semen cryopreservation. SDS, egg yolk and glycerol at concentrations of 0.03%, 15% and 5%, respectively, resulted in the optimum motility, acrosome, membrane and DNA integrities of equine spermatozoa. Increasing the concentration of glycerol above 5% appeared to have deleterious effect of sperm DNA manifested as increased in the percentage of fragmented DNA, DNA content in tail of comet, tail length and Olive tail moment. In conclusion, 0.03% SDS, 15% egg yolk and 5% glycerol are the optimum concentrations for cryopreservation of equine spermatozoa, and comet assay is a valuable tool to monitor DNA cryo-damage in stallion sperm.
Highlights
Cryopreservation of sperm is of great importance for the equine breeding industry, since it allows for long-term storage and transportation
sodium dodecyl sulfate (SDS) was found to be fundamental for cryopreservation of stallion spermatozoa and the ideal concentration of SDS in INRA-82 extender was 0.03%
High concentrations of SDS were found to have a detrimental effect on both motility and acrosome integrity of frozen–thawed goat spermatozoa (Aboagla and Terada, 2004)
Summary
Cryopreservation of sperm is of great importance for the equine breeding industry, since it allows for long-term storage and transportation. A large part of the stallion population, remains unqualified for semen freezing programs because of unsatisfactory postthaw sperm quality and fertility rates (Loomis and Graham, 2008). Stallion semen is generally cryopreserved using a freezing extender that consists of skim milk, egg yolk and glycerol as cryoprotectants (Salazar et al, 2011). Various laboratories have tested and proposed various freezing extenders of various compositions in an attempt to improve the quality and use of frozen stallion semen (Loomis and Graham, 2008). Palmer (1984) proposed the use of a skim milk-egg yolkglycerol freezing extender supplemented with an assortment of sugars and electrolytes for cryopreservation of equine semen (termed INRA-82) which has higher fertility as compared with Kenney’s extender (Ecot et al, 2001) Various laboratories have tested and proposed various freezing extenders of various compositions in an attempt to improve the quality and use of frozen stallion semen (Loomis and Graham, 2008). Palmer (1984) proposed the use of a skim milk-egg yolkglycerol freezing extender supplemented with an assortment of sugars and electrolytes for cryopreservation of equine semen (termed INRA-82) which has higher fertility as compared with Kenney’s extender (Ecot et al, 2001)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
