Category Archives: frozen semen

Semen Assessment as a Fertility Predictor

Posted: | August 29, 2026

Semen Assessment as a Fertility Predictor in Stallions Accurate stallion semen assessment as a fertility predictor need not rely on expensive equipment. This study investigated whether basic light microscopy assessments of sperm motility, membrane integrity, and morphology could reliably distinguish fertile from sub-fertile stallions under field conditions. Study Design: 24 frozen semen batches from 24 Arabian and Straight… Read More: Semen Assessment as a Fertility Predictor »

Automated Freezing Machine vs. Styrofoam Box

Posted: | August 29, 2026

Post-Thaw Sperm Motility Comparing Automated Freezer vs. Styrofoam Box Across Multiple Cryoprotectants Standardizing equine semen cryopreservation is challenging due to variability in freezing equipment and cryoprotectant selection. This study compared a computer-controlled automated freezing machine vs. Styrofoam box method across four cryoprotectant combinations to assess post-thaw sperm motility outcomes. Study Design: 4 stallions (ages 4–20); 4 semen collections… Read More: Automated Freezing Machine vs. Styrofoam Box »

Prostanoids as Markers of Oxidative Stress in Stallion Semen

Posted: | August 15, 2026

Prostanoids as Markers of Oxidative Stress in Stallion Semen Standard pre-processing semen assessment does not reliably predict quality after chilled storage. Oxidative stress in stallion semen during cooling damages sperm membranes via lipid peroxidation, reducing fertilizing potential. This study investigated whether seminal plasma prostanoids — established lipid peroxidation biomarkers — could predict chilled semen quality in stallions. Study… Read More: Prostanoids as Markers of Oxidative Stress in Stallion Semen »

Pre-Freeze Semen Centrifugation Extenders

Posted: | July 23, 2026

Pre-Freeze Centrifugation Extenders Selection for Optimizing Equine Semen Cryopreservation Cryopreservation exposes spermatozoa to significant physical and chemical stress, making pre-freeze semen centrifugation extender selection critical for maintaining sperm viability and membrane integrity. This study compared four extender formulations — with and without cholesterol and pentoxifylline — to identify the most effective option for pre-centrifugation use in equine semen… Read More: Pre-Freeze Semen Centrifugation Extenders »

Effect of Semen Extenders on Pre-Freeze Shipped Semen

Posted: | July 19, 2026

Protective Effect of Semen Extenders on Pre-Freeze Shipped Semen During Refrigeration at 5°C for 24 Hours Refrigerating stallion semen at 5°C for 24 hour shipment prior to freezing offers a practical field-based alternative when on-site cryopreservation is not feasible. This study evaluated the effect of semen extenders on pre-freeze shipped semen in four commercial diluents used within a… Read More: Effect of Semen Extenders on Pre-Freeze Shipped Semen »

Cholesterol Improves Cold Shock Resistance

Posted: | July 5, 2026

Increasing Sperm Membrane Cholesterol Improves Cold Shock Resistance and Cryosurvival in Stallions Stallion sperm are inherently sensitive to cold shock due to a low cholesterol-to-phospholipid membrane ratio (0.38–0.45), compared to cold-shock-resistant species such as humans and rabbits (0.88–0.99). This study investigated how much cholesterol supplementation — delivered via cholesterol-loaded cyclodextrins — is required to protect stallion sperm from… Read More: Cholesterol Improves Cold Shock Resistance »

Prolonged Storage of Post-thaw Semen

Posted: | July 4, 2026

Storage Conditions Affecting Prolonged Storage of Post-thaw Semen Field-based use of cryopreserved stallion semen is often limited by the equipment and expertise required for on-site thawing. Thawing centrally, then achieving prolonged storage of post-thaw semen and shipping it in a cooled state could simplify artificial insemination programs at locations remote from the laboratory or center, but optimal post-thaw… Read More: Prolonged Storage of Post-thaw Semen »

Cryopreservation Extenders Content

Posted: | June 27, 2026

Egg Yolk Concentration, Cryoprotectant Type, and Cooling Rate Effects on Post-Thaw Stallion Sperm Quality Cryopreservation extenders vary widely in egg yolk content and the type of penetrating cryoprotectant used, with prior evidence suggesting amide-based cryoprotectants may reduce oxidative stress compared to glycerol alone. This study examined how egg yolk concentration, cryoprotectant combination, and pre-freeze cooling rate interact to… Read More: Cryopreservation Extenders Content »

Donkey Semen Cryopreservation

Posted: | June 20, 2026

Donkey Semen Cryopreservation with Different Permeable Cryoprotectants Optimizing cryoprotectant selection for donkey semen cryopreservation is critical, as excessive concentrations can negatively impact recipient mare fertility. This two-experiment study evaluated cryoprotectant type and concentration to identify the most effective preservation strategy for Pêga donkey semen. Experiment 1 — Cryoprotectant Type (5 donkeys, 20 ejaculates): Five cryoprotectants compared at 5%… Read More: Donkey Semen Cryopreservation »

Epididymal Sperm Collection and Processing

Posted: | June 13, 2026

Epididymal Sperm Collection and Processing Epididymal sperm collection and processing represent the last opportunity for genetic material rescue following sudden stallion death or emergency castration. This study evaluated multiple collection and processing variables across 142 samples to develop a standardized, practitioner-ready protocol. Study Design: 142 samples collected from stallions undergoing elective orchiectomy (castration) Computer-assisted sperm analysis used for… Read More: Epididymal Sperm Collection and Processing »