TABLE 3.
Toxicity thresholds of selected toxins and chemicals for vitality parameters of boar spermatozoa
| Compound | EC50 (ng ml−1) that resulted ina:
|
|||
|---|---|---|---|---|
| Swelling of mito-chondria | Depletion of ATP | Loss of motility | Damage to plasma membrane | |
| Purified toxin from indoor S. griseus strainsb | ||||
| 8/ppi | <500 | >10,000 | 1 | >1,000 |
| 2/ppi | <500 | >10,000 | 3.2 | >1,000 |
| 10/ppi | >10,000 | 2 | >1,000 | |
| 1/k | >10,000 | 2.9 | >1,000 | |
| Cereulide | <400 | >1,000 | 0.5 | >1,000 |
| Valinomycin | <400 | >12,500 | 2 | >1,000 |
| Calcimycin A 23187 | >2,000 | 125 | 32 | |
| Gramicidin (mixture of gramicidins A, B, C, and D) | <3 | |||
| Ionomycin | >1,000 | 10,000 | 1,000 | |
| Polymyxin B sulfate | >50,000 | >50,000 | >50,000 | |
| Surfactin | >5,000 | 5,000–10,000 | 5,000 | |
| Enniatin | >5,000 | NDc | 300 | |
| Nodularin | ND | >40,000 | >40,000 | |
| Anatoxin A | ND | >40,000 | >40,000 | |
| N,N-Dihexylcarbodi-imide | 1,000 | 10,000 | >100, <1,000 | |
| 2,4-Dinitrophenol | >10,000 | >10,000 | <10,000 | |
Expressed as the endpoint dilution that resulted in a >50% change in the vitality parameter for extended boar semen compared to that of spermatozoa exposed to diluent only. Nodularin, anatoxin A, N,N-dihexylcarbodiimide, and 2,4-dinitrophenol were diluted in DMSO, and the other chemicals were diluted in methanol. Cereulide and valinomycin were diluted in parallel in methanol and in DMSO, but no difference in the endpoint dilutions was observed.
The toxic agent was purified from methanol extracts of S. griseus cultures, and the amounts of toxic agent were determined by reverse-phase HPLC by using commercial valinomycin as the standard.
ND, not determined.