RESULTS
Sperm motility, percentage of normal acrosomes and percentage of sHOST positive sperm cells decrease from day 0 to day 10 in R samples (Figure 2a). In D samples sperm quality was maintained until day 15 (motility 50 %, acrosomal status 37 %, sHOST 25 %) (Figure 2b). The level of DNA fragmentation is low and stable in R samples up to day 7, ranging from 0 to 4.25 %. From day 7 it increases significantly (p<0.03) and continues to increase up to the end of the experiment (0 to 43.25 %) (Figure 2a). However, in D samples, the level of DNA fragmentation remains low and stable along all the preservation period (0 to 4 %)(Figure 2b).
Individual differences have been observed in the DNA fragmentation level along the preservation period in R samples (Figure 3).
Figure 2. Evolution of semen quality and sperm DNA fragmentation in boar semen during 21 days at 22 days at 15ºC in two different preservation conditions. A: undiluted, b: diluted in ACROMAX®.
Figure 3. Evolution of the sperm DNA fragmentation in undiluted semen of 7 boars during 21 days at 15ºC.
CONCLUSIONS
From this experiment two main conclusions and two advices could be addressed i) boar semen samples show low levels of DNA fragmentation but individual differences have been observed ii) DNA fragmentation in no preserved samples increases since day 7 iii) Sperm samples extended in ACROMAX® have been protected against the processes that allow DNA fragmentation at least till day 15.
The new kit SPERM-Sus-HALOMAX® is a simple, easy to perform and quick test, to detect DNA fragmentation in boar sperm samples. The long term extender ACROMAX® protects boar sperm nuclei from DNA fragmentation in semen samples preserved at 15ºC during 15 days
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