SUMMARY
The serum calcium level of vehicle injected fish (group-A) exhibits no alteration throughout the experiment. Vitamin D3 administration to fish Heteropneustes fossilis exhibited hypercalcemia from day 3 to day 7 (group-B). However hypophysectomized and vehicle injected fish showed hypocalcemia from day 3 to day 7 (group-C). While hypophysectomized and vitamin D3 injected fish exhibited hypercalcemia on day 3 till the end of experiment (group -D). The serum phosphate of group A fishes is unaltered throughout experiment. The phosphate level of vitamin D3 treated fish (group-B) exhibits hyperphosphatemia from day 3 to day 7. In group C fishes exhibited a significant decrease in phosphate level throughout the experiment. While the group D fishes showed hyperphosphatemia from day 3 to day 7. In group E fishes the serum calcium level remains unaffected up to day 3 the level decreases on day 5 to day 7. In group F fishes showed hypercalcemia from day 3 to day 7. In group H fishes a progressive decrease in serum calcium level is noticed on day 3 to day 7. The group H fishes shows increase in the serum calcium level from day 3 to day 7. The serum phosphate level of group E fishes showed a decrease from day 3 to day 5. The phosphate level increases from day 3 to day 7 in group F fishes. The phosphate level exhibited a decrease from day 3 to day 7 (group G). The phosphate level increases from day 5 to day 7 of group H fishes.