Is it a good idea to pursue MA after B.Sc in zoology?

Not a great idea but good if you can start your own business after doing MBA, may be something related to Zoology. See, no degree goes waste. You are the better person to judge and think how can you make most of your MBA, if you are interested in doing it. Or else you should go for higher studies re

Yes, nothing can stop a Science student from pursuing anything, provided you have a honours as it is generally required for doing Masters, so if you have interest in arts, go for it.