Nowadays a large number of transgenic animals have been produced for various purposes. It is also seen that one cannot easily identify a transgenic animal and a normal animal.Are these transgenic animals in any manner harmful to humans?

Each type of transgenic animal would need to be specifically evaluated, and that is a very broad question. Harmful in any manner? I suspect no more so than a contemporary non-GMO animal. A specific exception would be if the animal were engineered to produce a substance toxic to humans, which we then ate. I know of no such animal. I would be far more concerned about the routine use of antobiotics by farmers and the potential to raise antibiotic resistance pathogenic organisms.