Toxicology
Human
Diet
Zinc plays an important role in spermatogenesis. A zinc deficient diet in mice caused increased DNA fragmentation (Evenson et al. 1980). Heat to testis. When a wool sock was placed over bull testes for 48 hours, DNA fragmentation was seen 3 days after the heat exposure (Karabinus et al. 1997). Mouse testes were exposed to a 38oC and 40oC waterbath for one hour. DNA fragmentation was seen at about 3 days after 40oC exposure but not after 38oC exposure, suggesting a heat threshold that will cause sperm DNA damage (Figure 3) (Sailer et al. 1997).
Figure 3. The 38.0 °C treated mice exhibited SCSA values similar to the controls for most days. Compαt (DFI) showed significant differences compared to controls with a return to control levels by day 35 (Sailer et al. 1997).