aggressive street dogs

Question
Hi. We live in Delhi, India where there is a huge street dog population. We live in an enclosed community where there are about 4 dogs to 2 0r 3 streets. They strictly maintain their boundaries and stay near people who throw some food. Each "family" is bound very much to the area into which they were born. Our street has a few dog lovers and some of us have sterilized a few of the dogs and feed them leftovers on and off.
Today we found one of the sterilized female dogs badly shaken and bloody all over. She was severely bitten in both ears and above the tail. Another pack of dogs must have attacked her.
I want to know  why this happens? Of course we know that the alpha dog has to show his supiority and this particular female was very submissive, but can dogs rape in a pack?
I have also witnessed a group of dogs attacking a cat, surrounding her and putting her in her mouth. Though she had no wounds at all, she died of shock. Normally these street dogs merely chase cats for fun.
Why do dogs attack when there is nothing at stake for them?
Thank YOU!
Sincerely, tina a Delhi

Answer
Dear Tina, Feral dogs will lack exercise, training an find their own ways of behaving because they do not have human leadership. Depending on the breed or breed crosses, they will revert to chasing, killing, establishing pack leadership and controlling territory on their own. This is natural behavior, such as you would see in a wolf or fox pack. Sometimes they will kill a weak or sick animal, kill for food, or merely play chase with each other, cats and people. If you have a rabies problem in your area, please be safe and stay clear of these dogs. Dogs do not think in terms of rape like we do. They will, however, breed dogs within and outside of their pack. A submissive female in estrus (heat) will attract males from kilometers away and they will breed with her, often causing her to have offspring from a couple of different males. In the case of the female that was spayed, her submissiveness may have been the cause of the attack. Dogs have a natural pack leadership behavior and if she was weak or submissive, they may have attacked her because she was not sure of herself, could not defend herself, was not a member of another pack, or many reasons. Male dogs will breed with a sterilized female, even though she is not in estrus. It is their way of continuing the species. They do not know she was sterilized, so they will breed her anyway if she is submissive and will not fight them off, especially if they approached her in a pack. If you have a local veterinarian that is willing to help, maybe you can get the community together to round up the dogs and sterilize them all, or most of them. This will help control the population so that you do not witness these attacks or any attacks on humans as well. Please leave me some feedback and follow up with me if you need further information. Feel free to contact me at my website at http://dogbehaviorist.org anytime. Thank you for writing. I wish you the best with these dogs. Warm Regards, Susan