Just over 43 minutes into the movie, when the dachshunds climb up on the bed with Fran, it is clear that one of the puppies is a male. Early in the movie, all of the dachshund puppies are said to be female.
When Brutus is barking up at the tree where he has the policeman trapped, there is a moving cloth reflected in the police car window which is the trainer enticing the dog to jump and bark.
When Brutus chases Sgt. Carmody he tries to open the door to his car but it is locked so he is forced to climb a tree. The next morning Mark Garrison sees the car and opens the driver's door and it is not locked.
At the party, Mark and the Vet Dr Pruitt take a large bone from a roasted joint of meat for Brutus to enjoy. Dogs should never eat cooked bones as they can easily splinter and lodge in the intestinal tract- a Vet ought to have known that and advised Mark accordingly.