Meeting Other Animals
Let him get to know other animals — cats, chickens, horses, goats, birds, guinea pigs, lizards, and of course, other puppies and dogs. Often upon meeting a new species a puppy is startled, then curious, and finally some become bold or aggressive. For his own protection and for the protection of the other animal, always keep him leashed so you can control his distance and stop unwanted behaviors by enforcing obedience commands.
Whatever you are socializing your puppy to — animals, objects, or people — approach the new thing in a relaxed manner and avoid any situation that would intimidate the average puppy, such as a group of grade schoolers rushing at him. Be prepared for three reactions: walking up to check it out and sniff, apprehensive barking with hackles raised, or running away.
No matter how well-socialized your pup may be, there will be situations where it would be unfair to trust him to ignore his instincts. For example, if your niece has a pet mouse and you have a Dachshund or a terrier, you can't expect that the mouse could safely play outside of its cage with your dog in the room. These dogs have been bred through time to hunt down such small animals.
No matter his response, remain silent. In the first (and, by the way, best) scenario he is thinking rationally and investigating his environment — don't draw attention to yourself by talking, praising, or petting. Allow him to explore uninterrupted. This good boy is entertaining himself and being educated at the same time. If your puppy lacks confidence or displays fear, don't console him because this will reinforce his fear. Use the leash to prevent him from running away. If he is still slightly uncomfortable, drop some tasty bits of food (like slivers of hot dog) on the ground. Most puppies will relax after a nibble or two because the uncomfortable situation has been positively associated with food.
If loud noises frighten your puppy, desensitize him by allowing him to create a racket. Offer him a big metal spoon with a little peanut butter on it. Give him an empty half-gallon or gallon milk jug with the cap removed and a bit of squeeze cheese in the rim to bat around. It won't be long before he is creating hubbub and loving it. Of course, if the clamoring drives you nuts, feel free to limit his playtime with these items. Also socialize your puppy to walking on leash, riding in the car, and being examined and groomed.
When introducing a new puppy to your current dog or cat, remember that your established pet considers your home its territory. If possible, try to introduce the animals in neutral territory, maybe in a friend's yard. It's very important to make sure neither of the animals becomes afraid of the other, or the other pet will quickly become a bully.
