introducing a new male dog

Question
Hi I have recently found a stray terrier X and would love to keep him.  However, he is very aggresive towards my own dog a 8 year old lab X.  The new dog I think is about 3 years old and both are male so I understand it's a territory thing.  When walking them together they are fine but once back in the house they fight instantly.  Ive tried introducing them through a childs stairway gate but I think this aggrevates the situation.  How can I get them used to each other?

Answer
You may be rushing things. With enough time and social distance most will slowly accept the new dogs in their lives.

You are most definitely doing it the hard way with two adult dogs! Better case scenario for success is a puppy and an older dog.

Try pairing good things only with the presence of the other dog. Avoid the quality alone time trap. You want the dogs to think "The only time I get steak bits is when that other guy is around-he's OK!" Do it on leash with some help at first if you are unsure if they will compete for food

Sometimes no matter what it's not a good match, if over time you see no improvement or things get progressively worse you may want to consider rehoming the terrier.

Some good books to read (www.dogwise.com) Fight! by Jean Donaldson or Aggression in Dogs by Brenda Aloff.

I hope that helps!