The Asian man who feeds the pups at the beginning of the film is speaking Vietnamese. He says, "You must be hungry. Eat a lot so you can grow up."
Contrary to popular belief, Fluke was portrayed by canine actor Comet (Buddy), known for his role in a few episodes of Full House (1987).
Nancy Travis and Matthew Modine previously appeared in "Married To The Mob."
In general, the dogs were very well trained in pre-production to respond to verbal and physical commands and were rewarded with food. In scenes where the animals moved from A to B or appeared to be chasing another animal, they were actually responding to a trainer's command and ran to another waiting trainer who rewarded the animal with a treat. When the animals appeared to be in an agitated state or growling, they were actually responding to the trainer's hand and verbal commands. During any attack training and during filming of the attack scenes, the dogs were prompted by a trainer who used both verbal and physical commands. The dogs were not bothered by this activity, but returned to a playful state immediately and then given verbal and food rewards. Another technique used by the trainers to give the appearance of agitation was to encourage play behavior with the use of towels, balls and noise makers.
In the scenes where the animal control "come-along" was used to capture the dogs, it was rigged so that the collar could not tighten around the dog's neck and the loop was padded with foam rubber. The trainer actually controlled the come-along during filming, placed the collar around the dog's neck, cued the dog to back up and was promoting play behavior that gave the appearance of the dog struggling.