Optimization of the Equine-Sperm Freeze Test in Purebred Spanish Horses by Incorporating Colloidal Centrifugation.
Authors: Gutiérrez-Cepeda Luna, Crespo Francisco, Blazquez Juan Carlos, Serres Consuelo
Journal: Animals : an open access journal from MDPI
Summary
# Editorial Summary A significant proportion of Purebred Spanish Horse stallions produce ejaculates that fall below international standards for semen cryopreservation, restricting the use of frozen artificial insemination in this breed. Researchers tested whether single-layer colloidal centrifugation prior to freezing could improve the freezeability of suboptimal ejaculates in clinical settings, whilst also comparing three different freezing extenders (BotuCrio®, Inra-Freeze®, and Lac-Edta) and their interaction with centrifugation method. Colloidal centrifugation more than doubled the proportion of ejaculates suitable for cryopreservation, increasing the freezeable sample rate from 35% to 71% of the 17 stallions studied. Whilst linearity and lateral head displacement improved significantly with colloidal versus simple centrifugation at 5 minutes post-thaw, all extenders performed similarly when combined with colloidal centrifugation. BotuCrio® consistently delivered superior post-thaw motility parameters across both centrifugation protocols compared to the other two extenders. For practitioners managing breeding programmes involving Purebred Spanish Horses or other stallions with marginal semen quality, incorporating colloidal centrifugation into the freeze-test protocol could substantially expand the number of individuals suitable for cryopreservation, making genetic material from previously excluded stallions available for frozen artificial insemination—particularly valuable for breed conservation and maximising genetic diversity.
Read the full abstract on PubMed
Practical Takeaways
- •Implementing colloidal centrifugation in freeze-testing protocols can double the number of Purebred Spanish stallions eligible for semen cryopreservation, expanding artificial insemination breeding options
- •For stallions with initially poor semen quality, colloidal centrifugation can recover usable frozen doses with quality equivalent to naturally good ejaculates
- •Selection of extender matters: BotuCrio® outperformed other extenders tested, particularly when combined with colloidal centrifugation
Key Findings
- •Colloidal centrifugation increased the percentage of ejaculates suitable for freezing from 35% to 71% in Purebred Spanish stallions
- •Colloidal centrifugation produced thawed sperm doses of similar quality from poor-quality fresh ejaculates compared to good-quality ejaculates
- •BotuCrio® extender demonstrated superior motility parameters compared to Inra-Freeze® and Lac-Edta when using colloidal centrifugation
- •Significant improvements in linearity (LIN) and lateral head displacement (ALH) were observed with colloidal versus simple centrifugation after 5 minutes at 37°C