Effect of sperm dosage transportation in stallions: Effect on sperm DNA fragmentation.

This study examines the effects of transport times and conditions on horse sperm quality, particularly focusing on DNA fragmentation. The findings suggest that while prolonged storage and transport of sperm can increase the fragmentation rate, stallion sperm can remain viable for up to 48 hours under cooled conditions.

Research Objective and Design

• This study had two main objectives: to determine the impact of transportation on the integrity of sperm DNA over different lengths of time following collection, and to find out if the quality of sperm DNA declines rapidly after 24 hours of storage at a cooled temperature.
• To achieve these objectives, the research design involved collecting and extending ejaculates using a specific extender (INRA 96). The semen was either evaluated immediately (A0) or after being stored and transported under cooled conditions for a period of either 24 hours (B24) or 48 hours (C48).

Methodology and Results

• The researchers assessed the Sperm DNA fragmentation index (SDFI) at four different points: immediately following collection, and after 2, 6 and 24 hours of incubation at 37 degrees Celsius.
• The findings revealed minimal differences in SDFI between freshly extended (A0) and semen samples transported under cooled conditions for 24 or 48 hours (B24/C48) at the time of collection.
• However, after 2 hours of incubation at 37 degrees Celsius, the SDFI of freshly extended semen samples increased between 2.7% to 7.5% per hour, whereas cooled-transported semen samples registered much higher increases, ranging between 5.0% to 20.5% (B24: 14.7% ± 5.6) and 8.2% to 26.8% (C48: 18.3% ± 7.2) respectively.

Conclusions and Implications

• The results suggest that while transportation and storage can lead to an increased rate of sperm DNA fragmentation, the differences in sperm DNA integrity between 24 and 48-hour transported samples are not significant.
• Consequently, cooled storage does not cause rapid deterioration of sperm DNA quality beyond 24 hours. This implies that horse sperm can be used effectively for artificial insemination even after 48 hours of being stored and transported at cool temperatures.