Sudden unprovoked aggression from usually soft-as-butter dog :(

[ViviPru]

My basset hound - of small, athletic hunting bloodstock, not the classic showdog floppy droopy clown-style basset - is coming up for 5. She's always been the most easy-going, amenable and gentle dog. She's with us 24-7 and usually in tow wherever we go, so used to all manner of situations and people.

She was rehomed with us at 9 months, and has always been a bit nervy with men in hats, we don't know why. As she's grown older and more confident, she has on occasion shown some very mild aggression if she's approached or startled by one, but other than that (and on occasion growling at staffies after an incident 2 years ago, not a staffie bashing thread) she would never be described as an aggressive dog.

Earlier this week, we were passing two ladies deep in conversation with eachother, I had hound on a close tether as it was a narrow path. I greeted the ladies and as we drew level, totally out of nowhere my dog sprang up at the closest lady to her and 'grizzled' (not quite a snarl), and mouthed her sleeve. It was not a bite, but it was way more aggressive than I've ever seen her be without provocation. I was mortified, much more so than the lady. I put it down to the lady wearing a hood, but it wasn't as though she took hound by surprise. And then my Mum was walking hound today and she told me she'd done a very similar thing to a teenage girl she passed in the street. this girl was not wearing anything on her head.

I'm really upset, and not sure whether this is really serious or just a couple of incidents that don't necessarily indicate a major problem. I don't know what's caused this change in character, or if it even is a change in character. If we've ever had any mild behavioural problems with her in the past, we've overcome them with positive reinforcement, but I'm not sure how we can do that with this as it seems so indiscriminate and unpredictable.

I've tried googling but there's just so much out there its hard to know where to start. She's always been so sweet natured, I'm scared that she's not the same dog, I don't know if I can trust her, and I'm also scared she might go further.

If anyone has any advice/experience of this please share, I'm feeling really

You MUST take her to the vet as soon as possible as it's very important to rule out a physical cause. There's no point going to a behaviourist until you've done this and any good behaviourist won't see you until you've been to the vet anyway.

After that you need to call in a qualified behaviourist to help you. Make sure they're APDT registered.

I'd second Rhinestone - illness can make anyone bad tempered.

Yes, definitely go and see the vet.

APBC is probably a more appropriate accreditation to seek in this instance.

I agree with the advice here but would also advise getting a comfy basket muzzle for use when out and about, at least until this is addressed. You need to be sure that she's nor posing any risk to anyone.

Oops, thank you ohbugrit I meant APBC. APDT is a US organisation, they probably wouldn't fly over just for your dog!!

Ok, thank you. I will get her to the vet ASAP.

Just to endorse what Rhinestone and others have said. Could be an eyesight, ear or even teeth problem that is making her grouchy. Have seen all of these act as triggers for unexplained behaviour like you've described.

Hope all is well soon.

Thanks everyone for taking the time to reply. She has an ongoing issue with her lip, she gets sores on one side where her drool collects. Her treatment is ongoing, but the condition is particularly bad at the minute. The vet thinks it could be that which is agitating her and making her behave out of character.

In the meantime, I may consider the basket muzzle suggestion and we're going to make an effort to spend some time doing some general training with her, just to reinforce her role as the dog who we are in charge of.

Does aggressive behaviour subside once the physical ailment clears up? The vet wouldn't be drawn on this...

I am glad that you have had her checked out. Generally if her behaviour is caused by feeling poorly as she feels better her behaviour should change.

However she has made it clear to you that she is uncomfortable in some situations so you need to watch out for that.

The APDT is a training association and I would recommend you contact them as they can help with training and changing her behaviour. It is available in this country link here. You could contact the APDC however this sounds to me like quite a simple training issue that can be and has been corrected by APDT trainer regularly.

She has shown anxious behaviour before eg men with hats etc and usually this will increase rather than decrease over time unless it is dealt with, so her new behaviour may just be an extension of this.

You do not need to show her who is in charge - in fact this will make her worse - what you do need to do is make her more confident. This can be achieved by many techniques which the APDT will use. Eg clicker training or BAT.

I can explain more if you need to but you may already know this so don't want to bore the pants of you!

Brilliant useful post, thanks minimuu, I'm checking out that link now.