New Puppy in Home with Existing Pet

Question
I have a 10 year old toy poodle/jack russell that is a member of our family.  My daughter brought home a 8 week old border collie/boxer mix female puppy two weeks ago.  My 10 year old dog is totally freaked out by the new puppy being the house.  He avoids the puppy at all times and twice now within the past five days he has bitten into the puppy's snout where it actually bleeds.  I hate that my dog is so upset about having the puppy and I hate it for the puppy because she is only trying to play.  We give plenty attention to both animals and try to make each feel special.  We have not changed the 10 year olds' routine and tried to act normal.  The puppy sleeps in the garage but is in the house during the day.  The 10 year old pretty much stays hid in a closet all day until I get home from work (my husband is at home during the day).  Since the 10 year old is actually biting the puppy, what advice do you have?

Answer
Once past 3 years old, many dogs don't want anything to do with puppies, their sharp little teeth, and their biting games.  You need to teach the puppy to leave the older dog alone.  As soon as the puppy starts to focus on the older dog, give it a sharp ''Ah, ah, ah!'' and offer it a chew toy.  

When you aren't around, crate the puppy.  It is only natural that a puppy resists its crate at first. What the puppy wants more than anything else is to be others, you, anyone else in the household, and any other pets. In our modern society, even if we are home, other things distract us from the attention an uncrated puppy must have. The only real solution is to crate the dog when you aren't around. The dog may be happier in its den than loose in the house. It relaxes, it feels safe in its den. It rests, the body slows down reducing the need for water and relieving its self. Dogs that have been crated all along do very well. Many of them will rest in their crates even when the door is open. I think the plastic ones give the dog more of a safe, enclosed den feeling. Metal ones can be put in a corner or covered with something the dog can't pull in and chew. Select a crate just big enough for the full grown dog to stretch out in.

Leave it some toys. Perhaps a Kong filled with peanut butter. Don't leave anything in the crate the dog might chew up. It will do fine without even any bedding. You will come home to a safe dog and a house you can enjoy.

A dog that has not been crated since it was little, may take some work. Start out just putting its toys and treats in the crate. Praise it for going in. Feed it in the crate. This is also an easy way to maintain order at feeding time for more than one dog.