You can visit the Tata Steel Zoological Park between:
The zoo is closed on Mondays
The zoo remains open to visitors on all National Holidays
However the best time to observe animals in their prime activity is 10:30AM to 12:00 Noon all seasons. Later as the day progresses, many may be seen lazing in the open yard or in their feeding / resting cubicles. Do not tease or provocate them.