The aim of this study was to determine whether there was an increase in pregnancy rates when frozen-thawed stallion semen was processed by single layer centrifugation (SLC) through a colloid before insemination. In addition, changes in semen parameters, including motility, were determined before and after SLC. Twenty light-horse mares (aged 3-16 years) and one Thoroughbred stallion (aged 16 years) having average fertility with fresh and cooled semen (>50% per cycle) and displaying a postthaw motility of >35% were used. Control mares were inseminated using 4- × 0.5-mL straws (200 × 10 6/mL) of frozen-thawed semen. Treatment mares were inseminated with 4 × 0.5 mL of frozen-thawed semen after processing by SLC. Pregnancy rates were compared using Fisher exact test, and continuous parameters were evaluated by a Student t test. The pregnancy rates at day 14 were not different for the mares inseminated with control versus SLC-processed semen, despite the difference in sperm number (171 × 10 6 ± 21, 59 × 10 6 ± 25 progressively motile sperm). After frozen-thawed semen was processed by SLC, the percentage progressively motile sperm improved (P < .05), and SLC processing resulted in a 21.8% recovery of spermatozoa. In summary, centrifugation of frozen-thawed semen through a single layer of colloid increased the percentage of motile spermatozoa, but did not improve pregnancy rates after deep horn insemination.
|Number of pages||3|
|Journal||Journal of Equine Veterinary Science|
|State||Published - May 2012|
Bibliographical noteFunding Information:
The authors thank Cecilia Hylton and the Cecil and Irene Hylton Foundation for funding this study. They also thank Dr. Ball, Dr. Klein, Dr. Scoggins, Dr. Petersen, Dr. Campos, Lauren Keith, Kevin Gallagher, and Chad Tucker for their help and support, and Hagyards Equine Medical Institute for the use of their nucleocounter.
- Single Layer Centrifugation
ASJC Scopus subject areas