Also:
Couple of things there -- to some extent some animals *can* make "compacts" with us, so that needs to be considered. Even to those animals that aren't subject to domestication or similar "compacts" there will still be a significant issues of pleasure and pain, just as you suggest. So again the main point is that there may be many ramifications to consider in dealing with a particular biting dog, but those ramifications do not include any concept of "justice" tied to supernatural beings or absolute standards of morality.
As to whether a particular action with a particular animal will lead to greater long-term pleasure or less long-term pain, that's going to be like most decisions -- subject to the circumstances and conditions then and there existing. I suspect your suggestion makes a lot of sense in most cases we ordinarily confront, but I would suggest also that it's generally dangerous to prejudge whether forgiveness or punishment is more likely to be the best course. That's because if you overgeneralize you are skirting near the error of thinking there is an absolute rule. It's always important to know the facts and not let rule-making get too abstract.