I know this is an ollllld question, but for future readers, we'll add that our St. Bernard/Border Collie mix (just verified in testing) weighs about 80 lbs (full grown). As others have said, this is one wonderful mix of a dog. Great with kids, very smart and trainable, gentle, loves petting, playful. Downsides: Sheds like crazy in spring, needs to be kept cool (we live in CT but keep a little "pool" filled with water for him in the summer; he literally lays sprawled on the ice in winter; lucky for him we adopted him--from a shelter in GA!), needs a yard to run around in, fine and even submissive with female dogs, but aggressive with male dogs. Ours is blue-eyed!
Saint Bernard is one of the largest breeds of dog. While your puppy might have Border Collie genes, there is no knowing what parent it will take after with regards to size and weight. You should be prepared that he might grow to the size of a full size St. Bernard male, which will put him between 160-240 pounds (72.5 - 110 kg) and his height will be between 27.5 inches and 35.5 inches (70-90 cm). He'll reach his full size at about the age of one year and six months, but might slowly continue to grow till he is two years old.
It is, however, possible that he will be much smaller like his Border Collie parent and this will make him a bit smaller than a German Shepherd. It is important that you feed him well. I would suggest that you start by feeding him twice a day and observe the amount he eats, slowly increasing this as he grows.
I have a Collie/ St. Bernard mix that was dropped at home along with his sibling about 8yrs ago. I couldn't resist the little ball of fur, but was also fearful on large he would get. He has the markings of a st. Bernard but is more the size of a collie with long hair. He weighs in at about 80lbs. I have to say this is best dog I have ever had. He's a great watch dog and the perfect family dog. Great with kids and other dogs and cats. Very loyal and would snap at the chance to have another mix like him.
3 yr old - 65 pounds (only about 1/4 saint-bernard, 3/4 rough collie), but much bigger than a collie, looks huge, but amazingly gentle, great family dog, very calm, very protective of the family (and smaller dogs) when outside. Loves to be petted. Amazing character!
I have this dog and is big like saint bernard and have the colours of collie is 55kg and is very cute but huge and in the summer need cold or aircondition all day...excuse my english.
We now have an almost 5 month old Border Collie/St. Bernard mix that we adopted from the local Animal Shelter. He has a mix of the St.Bernard markings beginning to show, but for the first 4 months was primarily marked like a Border Collie pup. His feet are huge! He now weighs in at 51.4lbs as of yesterday, and he continues to grow more and more every week.
He had/has a bit of a nipping problem when he is stressed or scared, but we are working hard to reassure him and provide structure for other types of behavior to replace mouthing (he has such razor sharp teeth.) He is a little too frisky for our older Husky mix, so they don't really play and we are looking for other dogs to socialize him with.
He loves to play, and is obsessed with picking things up and putting them in his mouth, just like any young'n I suppose. ;) He's going to be a big boy, but he's already a gem in the family.
