Four subpopulations of boar spermatozoa defined according to their response to the short hypoosmotic swelling test and acrosome status during incubation at 37 degrees C.
This study was designed to confirm the previously observed relationship between response to the short hypoosmotic swelling test (sHOST) and acrosome resistance in boar spermatozoa. Ejaculates from 22 boars were incubated in a water bath at 37 degrees C for 2h. During the incubation period, samples were taken at 5, 20, 40, 60, 90 and 120 min and subjected to the sHOST. sHOST responses (positive HP-negative HN) and acrosomal status (normal or intact NA-damaged DA) were evaluated in 100 spermatozoa corresponding to each ejaculate and incubation time, and the results used to establish four subpopulations: HPNA, HPDA, HNNA and HNDA. Over the entire incubation period, the sHOST positive subpopulation with damaged acrosomes, HPDA, was significantly smaller than the sHOST negative, damaged acrosome subpopulation, HNDA (P<0.001). Further, proportions of HPDA spermatozoa remained stable throughout this period while the HNDA subpopulation showed a significant increase (P<0.001) from the start to the end of incubation. These results confirm the high resistance of the plasma membrane of HP spermatozoa allowing the persistence of a higher number of intact acrosomes over time, compared to HN spermatozoa. Characterising this HPNA subpopulation may help the evaluation of ejaculate quality.
D000177:Acrosome / Q000648:ultrastructure*; D000818:Animals; D048429:Cell Size; D007038:Hypotonic Solutions; D008297:Male; D013081:Sperm Motility; D013094:Spermatozoa / Q000002:abnormalities / Q000145:classification* / Q000648:ultrastructure; D013552:Swine
D007038:Hypotonic Solutions