momma dog killed 5 week old pup

Question
Hi my dog had an OOPS litter(my male boxer that i got from a rescue was supposed to be fixed) 5 weeks ago Wednesday. She has been an awesome first time mom, cleaning them, nursing them the whole deal. i Came home from work last night to find that she had disemboweled one of the puppies and eaten her "guts" for lack of a better word. the puppy had started out on the small side when she was first born but had grown alot and was almost the same size as her siblings.I have since separated her from them when i am unable to be in the room to watch her with them. What would have caused her to do this? i know that animals sometimes kill their young when something is wrong with them but wouldn't she have sensed it before 5 weeks? also will the other puppies be effected by seeing this? Ever since this happened they have been quite and not like themselves.

thanks, Christie

Answer
Hi Christie

Don't don't think like we do, the pups wouldn't be effected by a missing sibling.

A dam can tell when a pup is born that it is unhealthy or sickly and will usually kill or push a pup away immediately.

Because you didn't witness it, she may have been cleaning and got carried away.  It's best to keep her separated from the rest of the litter only going in to feed.  The pups, at 5 weeks are old enough to start kibble.

Good luck