Our oldest bitch(she is nearly 6) has started keeping her mouth open for long periods of time. We only noticed it yesterday but she has started doing it agian this morning. It looks like she is panting, her moth is only open at the front not the sides and her tongue isn't moving, but isn't. She won't close her mouth after having a drink(she is not normally a drooly kind of dog) and when she shook before I noticed she didn't close her mouth. She is eating ok but drinking a bit more, suppose her mouth is dry. Apart from that she is fine, is it worth taking her to the vet? Or is there another reson for this stange behaviour?
Thanks in advance

Take her to the vet. My friends golden suddenly started doing this and it turned out she had injured her face and the muscles were not working properly. Another dog I knew who did this had a sore mouth which needed treatment. That is just two examples, there could be any number of reasons but it does not sound right.

I'd take her to the vets - it could be a dental problem, or a palsy which is triggering this behaviour.  Hope she's back to normal soon.

..yes definitely see the vet , it could also be a problem with the nasal passage or swelling on the tongue . Hope your dog is ok :-)

Just thought I'd reply to tell you how Chloe is now. We took her to the vet on Thursday evening and saw a nice but young vet who had never seen this problem before and said it could possibly be a sprain of the jaw muscles. She prescribed anti-inflams and to make another appointment if she was not any better by the end of the weekend. This vet is very nice and has been our youngest girls vet since she was 6 and a half weeks old but we weren't convinced. Needless to say she wasn't any better by Sunday so we had her to the vet this evening and we got a diagnosis off the head vet. She has Mandibular neurapraxia and he had actually seen it before. It is caused when the nerves supplying the lower jaw become damaged, usually from over opening of the mouth which means the mouth will not then close properly. She is still eating and drinking ok, for a vizsla anyway, and he said she should be back to normal within 3 weeks. This is great news as we were thinking allsorts(as you do)and we have our first ever open shows lined up for next month so now we can go ahead and enter!
Thanks for your kind words, very much appreciated and we are glad she is ok, although will continue to look gormless for a few weeks yet!!!
Emily