Does anyone have a Saint Bernard with some possible behavioural problems
Mine is 14 months old and reminds me of stitch out of kilo and stitch she's good 90% of the time but for the other 10% she can be a really right hand full I don't know whether this could be due to her being a puppy still as they mentally mature at a slower rate takes about 2 years for a big dog or it's just her. She can be very destructive eating shows destroying sofas etc. She's brilliant on the lead never once pulled when walking normally but she doesn't like being on the lead so will bite and growl on the lead and ends up biting me because I'm holding it but she never breaks the skin I was wondering if anyone could give me some suggestions please.

She doesn't sound like she's got behavioural problems, she sounds like a normal puppy which is exactly what she is. Giant breeds take much longer to mature than small breeds do, and whilst yorkie size could be considered mature at 7 months, a great dane sized dog can take up to 2 years to mature.

When she's being destructive is it when your out or not around? She might be doing it out of boredom or anxiety so a stuffed Kong would be a good idea to help keep her occupied and take her mind off the fact your not there. You will probably get a lot of filling in a St. Bernard sized Kong, so if you do give her one, remember to alternate her main food to make up for it, she's still growing and being too big on such a large dog puts enormous strain on their frame.

It's great she walks well on a lead, being taken for a walk by a dog that size would not be fun, but if she's biting at it, unless you train her 'no' or the 'leave it' command, the quickest way to stop her is to temporarily swap your regular lead for a chain one. When she goes to bite the lead she will get a very unpleasant shock, which should stop her in her tracks. If she's catching you, wrap the chain once around your hand so that when she bites you she also catches the chain. Dogs don't like the sensation and feel of chain so once she realised it is nasty to put her teeth on, she will leave it alone. Keep the chain until she makes no attempt whatsoever to grab the lead, then if you want you can swap back to your regular one, but alternate them for a short while. If you swap them back straight away, if she goes to bite and realises she can again you will have a harder job that if you trick her into thinking the lead is permanently unchewable. Normally though, one chomp at the chain is enough to put them off lead chewing for life.

The alternative to that is Grannick's Bitter Apple Spray, which when sprayed on the lead should stop lead biting, and you can also spray it on your furniture as a deterrent for that at well.