agressive pup

Question
Hi Labman,

my 6 year old golden retreiver has been acting agressive and peeing and pooping in the house (which is COMPLETLY out of his normal behaviour). We walk him every day, let him out as much as we always have and give him love and affection every chance we have. For the past few days he has made a mess of the house, peeing and pooping everywhere, trying to open the cupboard where the garbage is and knockin toilet seats off the toilet. He also showed his teeth to my sister today when she was punishing him. Could you tell me if this is just a bad time of eyar for him or if it might be a result of 5 days of rain...I'm really not sure what to do. Could he be sick?
Thanks:)
Kate

Answer
The first step is definitely a trip to the vet.  It is unusual to see a change in behavior like that at 6 years old.  If he isn't neutered, a female in season up wind can cause trouble.  Neutering him will both improve his behavior, and also reduce his chances of cancer later in life.  

I am a little concerned about the punishing him.  Usually by 6 years old, you have established good habits and a dog seldom needs correction.   The key to most behavior problems is approaching things using the dog's natural instincts.  Dogs see all the people and dogs in the household as a pack with each having their own rank in the pack and a top dog.  Life is much easier if the 2 legged pack members outrank the 4 legged ones.  You can learn to play the role of top dog by reading some books or going to a good obedience class. A good obedience class or book is about you being top dog, not about rewarding standard commands with a treat. Start at http://www.dogsbestfriend.com/  For more on being top dog, see http://www.dogbreedinfo.com./topdogrules.htm  While being a strong leader is important, a top dog is not a drill sergeant, but more a strict, but loving parent.