**5.5 Comparison of light duration during light/dark (LDLD) transition box test among the different experimental groups**

The mean ± SEM light duration for the control, CdCl2 (14 days), CdCl2 (28 days), CdCl2 + Zinc, and CdCl2 + vitamin E groups were 215.00 ± 12.98, 86.55 + 17.09, 72.48 ± 13.87, 218.37 ± 15.87, and 236.24 ± 18.35, respectively.

Results showed that the CdCl2 group's time spent in the light chamber was substantially shorter (p < 0.05) than that of the control group. The light chamber duration was substantially longer (p < 0.05) for the CdCl2 + Zinc and CdCl2 + vitamin E groups than for the CdCl2 group (see **Table 1**).
