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Socialization is the process of introducing a puppy to new situations so he learns to interact properly. Introducing your puppy to new situations and people teaches him that the right things (such as other friendly dogs, cats, and people) are not to be feared. Fearful dogs can become "aggressive" if they bite and bark when they cannot run away from the situation. Running away from things that should not be feared can be dangerous. Dogs can run into traffic and get hit by vehicles or run away from home and get lost. Once he's current with vaccinations, you can take him to parks, for walks along busy streets, other dog-friendly places, or enroll him in obedience school. If there are no obedience classes in your area or if you are waiting for one to start up, you can start on basic commands and socialization. You can also take him to crowded areas so he can watch new people and things. You should try exposing your dog to as many different things as possible. For example, take him for a short car ride and stop every once in a while to let him check out his surroundings. Or, invite friends and their pets over to meet your dog. Let him interact with all different types of people and animals. Don't force or rush your dog to socialize. If he's fearful around new animals, don't constantly make him interact. Instead, take it slow and move at a pace that's clearly comfortable for him. If you do, your Jack Russell will learn to be nervous and aggressive with other dogs. Instead, try to keep him on his leash and keep him beside you when other dogs approach. If a stray or aggressive-looking dog comes up, leave the area quickly with your Jack Russell in tow. On the other hand, Jack Russells can be overly aggressive towards other dogs, even other Jack Russells. Since Jack Russell Terriers are hunting dogs, it's in their nature to be aggressive. You should never leave your dog unattended with another dog, even another Jack Russell Terrier. For this reason, you shouldn't have a Jack Russell Terrier around small children, small animals or pets, or cats. To curb some of your dog's aggression, keep him well exercised and active. Bored Jack Russell Terriers are more likely to be aggressive or destructive. Since your Jack Russell may think he's the top dog, let him know that you are the master. For example, after he's learned the sit command, make your Jack Russell sit for his food before you let him eat it. Be firm and consistent with him. Don't just let him do whatever he wants. You can take him for a long walk or play active games. Jack Russells are very smart and will keep you hopping unless they can find an outlet for all their pent-up energy. Playing active games such as fetch will help burn off their excessive energy. Terriers love this game. Jack Russells love when you chase them for the toy. Don't make this a habit, or your dog will learn not to come to you when you call him. Instead, teach him the "drop it" command. This way, you're still in charge of the game. These can help burn your Jack Russell's energy. Kongs are great toys because they're almost impossible to tear apart. You can pack them full of peanut butter and treats to keep you Jack Russell busy and working for his snacks. Generally, stuffed toys aren't great for terriers, even though they love them. Your Jack Russell will probably tear it apart and try to eat it piece by piece leaving your home covered in stuffing. Choose a high-quality dog food that isn't filled with grains or preservatives. Instead, look for a dog food that lists meat, such as lamb or chicken, as a top ingredient. Since dog food products vary, follow the specific feeding instructions on the package. You'll probably also need to adjust the amount food you give your Jack Russell Terrier based on his age, activity level, and size. As a general guideline, a 12 inch Jack Russell Terrier should weigh around 12 to 13 pounds.
Understand why socialization helps Jack Russells. Socialize your Jack Russell. Don't pick up your dog when other dogs are around. Monitor your Jack Russell Terrier around other dogs. Teach your dog his place in the family. Exercise your Jack Russell at least twice a day. Buy really durable chew toys. Feed your Jack Russell a nutritious diet.