Snapping at Owners

How long has it been since he's had a really solid health evaluation?  I know others will be along with behavior advice, but since he's been on MAO Inhibitors a LONG time, you need to have bloodwork done a.s.a.p.

The MAO Inhibitors like prozac raise heck with the liver -- and an "unhappy" liver will make a dog darned grouchy --

My other suggestion -- and this may sound odd -- but is to try adding a vet who does TCVM (Traditional Chinese Veterinary Medicine).  A whole lot of what you describe as Bullwinkles initial reaction to the loss of his buddy truly sounds like stress-induced petit mal seizure activity.  Lots of obsession, that manifests in panic and bizarre behavior *some* of the time.

That honestly SO describes the little peke Kee Shu when she came to us -- she came out of a very difficult situation but altho not aggressive, she was a mass of little coping mechanisms and weird behaviors. 

I took her to a TCVM vet who treated her with herbs -- wow, a year later you would not have believed it was the same dog. 

Things that come out of health issues (usually health issues that have gone undiagnosed) tend to be BOTH habitual and health related.  But that's also why JUST behavior modification often doesn't work well.

First off - please have some bloodwork done.  (a thorough senior blood panel is a must at that age anyway) -- then if you go to http://www.tcvm.com -- there is a locator on the left.  If I can help you with the process of choosing a vet let me know -- I've used it now with huge success for years on many of my dogs. 

I'm not talking about you 'leaving' your vet -- not at all.  This is complimentary therapy but man, it can be like night and day very often.

Ditto what Callie said!

Labparents

Bullwinkle is jealous and after initial battles they now co-exist with Bullwinkle keeping dominant by barking and intimidating Buddy

And you let this happen because?

 To be honest, I think the addition of the second dog was a mistake.  Your dog had formed a strong bond with the first dog, and I believe he relied on that dog heavily for guidance (thus, you don't have a dog that wants to intimidate, you have a dog that is in self preservation mode).  Plus, he was used to sharing the home with a female, and you got him another male, larger than he - that's pretty scary for a dog that had been social with only one other dog, and who never learned to rely on the humans for guidance and not his canine companion.  It sounds as though he had not had much experience with others and would naturally be fearful of a newcomer anyway.  This scenario often happens in households where the humans don't realize that they aren't giving each dog the amount of socialization that's needed when the puppies are very, very young, or they adopt an older dog that did not have those experiences when young.  If you took both dogs everywhere together, and did not attend training classes separately with each, or if you did, only on a limited basis, maybe one puppy class, you probably inadvertantly contributed to his not being able to do without her when she died.  When I train puppies, they start class at age 8-10 weeks!!!  And, they continue with classes or other social experiences with other dogs outside the household until adulthood. 

Without seeing your dog, it's hard to interpret why he growls when you attempt to pet him, but you may want to consider having your vet do a thorough exam, including a repeat thyroid panel and a snap4dx test to make sure he has not contracted Lyme or other tickborne disease that could make him sensitive to touch, or painful in his joints or spine.  Also consider testing for vision problems (many ill bred Labs have PRA, or progressive retinal atrophy, which breeders are now able to avoid with a simple test).  If a physical issue is ruled out, then it's time to retain a good trainer or behaviorist to help you re-educate your dog, in a positive way, that humans touching him is a *good* thing.  That's usually done through desensitization and conditioning.

spiritdogs

When I train puppies, they start class at age 8-10 weeks!!!  And, they continue with classes or other social experiences with other dogs outside the household until adulthood. 

And dogs pick up new behaviors throughout their lives so outside classes are always beneficial. Keeps us thinking proactively so we can help them once a new behavior shows up that we don't like so much.

PS--Poor guy sounds like a very anxious dog who's living in flight/fight/fright mode. Is there anyway you can rehome the newer dog?