Hi,
I was woundering if anyone could shed some light on this my brother has a cocker, male, entire about 5 i think and he has started to growl at him and other family members, hes bit his step daughter unprovocked (shes 14) and recently snarled showing teeth at his oh.  Hes always been a happy friendly dog to my knowledge and its out of character and got worse over the last few months, i did wounder if it could be rage syndrome? i'm having troule finding info on it, hes been to the vets and is waiting for a blood test result, seems in good health as you can imagine they are upset and any info would be appriciated. (i did suggest contacting the breeder to see about other litter mates etc)

It certainly does not fit the pattern to develop signs of rage so late in life but contacting the breeder does seem a good idea not least to let them know what is going on for their own reference.  I think you need to wait for all the results of the vets investigations though to do anything but speculate.

Have his ears been checked.  Spaniels are more prone than most to ear infections and having had a bitch with prick ears with a severe infection earlier in the year without showing outward signs of pain I know that it can be missed until it becomes very painful and severe.

I would also see about getting his eyes checked by a specialist opthalmologist if his sight is deteriorating then he may be startled by what we would consider normal movement.

well he has been checked over by the vet, but on one occasion he was being called by his owner on he started to approch her and then started growling showing teeth etc, one minute they can be stroking him and hes fine, and they he will just start growling for now aparent reason, epilapse was mention as a possible course??

Brain tumour? Or maybe liver disease, I know someone years ago whos dog went like this, he had a problem with his liver, can't remember what now sorry. I would certainly want all the tests done that have already been suggested, its such a shame when this sort of thing happens. I feel really sorry for the owners.

Thyroid dysfuntion (the most common Immune related problem in dogs) can manifest as aggresion.

Has he had a very thorough physical exam?  My first thought would be thyroid, but physical pain can be very well hidden by dogs and manifest as aggression also.  He may not show any other signs of it than his behaviour, not even limping or the like.

I would be asking to have him refered to one of the animal university hospitals, if their pocket or insurance allows it. Have a good barrage of tests, get him seen by a specialist should something be found. It does need acting on quickly, before someone is harmed, which would be heartbreaking for the owners.

Hes always been a happy friendly dog to my knowledge and its out of character and got worse over the last few months

If this is the case, then it's more than likely to be a medical problem unless the owners can think of some cause that may have triggered it, somehow.
Have they changed the way they treat him, or is there any environmental change which could cause stress?

Lindsay
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