My thing is I am reading several psychology books--not textbooks--but folks personal perspectives and they asked how does smacking a child around teach him or her anything about better behavior?
And the trainers do not do it with the animals they train... Hence their minds are not much more than a human 4-6 year old--therefore, if we can do it for Shamu then how come we cannot do it for humans? At least this is the current thought for disciplining children in the books I am reading.
I think corporal punishment should be in place for kids. I do not think it should borderline abuse, be it physical or verbal. However, that the child will know when behavior is appropriate and when it is not. When it is acceptable and when it is not.
Also, the animal trainers also ignore a baby's cries when everything has been done, such as feeding, burping, changing diapers (if a primate) and bedding. Babies do need coddling for appropriate neural connections to form. Most people barely give them that, so the connections fail to form. However, animals and humans are strikingly different--animals are always in survival mode; whereas humans are
thought to use higher ordered intellect to outsmart their would-be predators.

We are not always taking flight or fighting--yet...