My first bird dog was a Brittany. I was just starting my first job out of graduate school at a small college in SW Michigan. My wife and I moved there in early September, and the pup was born in July, so I'd guess she was about 8-10 weeks old when we got her. She was already pointing bird wings on a fishing line at that age.
There was a retired farmer and his wife who owned a place with about 170 acres, and we rented it while they went to Florida for the winter. It had a lot of pheasant, Bobwhites, and a few grouse on the place. My dog got to go on a lot of walks on the place at a young age. We had our first snow around the first of October, and on one of those walks I saw some pheasant tracks ending in a big grass clump. I walked her downwind of the clump, and when she hit the scent she froze on point. I flushed the bird and she was hooked. I don't remember whether I actually shot a bird for her that fall, but over the next few years she got quite a few and became a pretty good upland dog.
The next spring my wife, the dog, and I were in a canoe on a lake in the Upper Peninsula. A butterfly came by and the dog tried to grab it, but ended up falling in. It was the first time she went swimming, and she did not like it at all. Ever after if a bird involved water she wanted no part of it.
She was very good at finding birds, and holding point until I arrived, but then would flush them (I know, not proper for a pointing dog). She was also good at retrieving cripples, but if it was dead, it was my responsibility - she was off to find another live one. As a youngster she loved to play fetch with a bumper, but once I tried to force-fetch her she wanted nothing more to do with that game.
She was about ten when we moved to Idaho and had a couple more years of hunting. She was about thirteen when I had to put her down with bladder cancer.
She was between thirty-five and forty pounds and a house dog all her life. All my dogs since then have been retrievers, one black Lab and the rest Chesapeakes. I would consider another Brittany if I did more upland hunting, particularly when the weather was warm, but most of my bird hunting now is colder weather, water, and heavier cover. For instance last week a friend and I went out on the Bear River on the last day of duck hunting. It started out at around ten degrees with a lot of floating ice on the river. His Lab was a little reluctant to get in at first, so my Chesapeake Rocky ended up retrieving all of the birds. He didn't mind the cold at all. I might have gotten my old Brittany in once by throwing her in, but she wouldn't have retrieved the bird, and I couldn't have caught her to throw her in a second time. On the other hand I probably would not take Rocky on a warm weather chukar hunt without a lot of water for him to drink or a river to jump in. You should use a dog appropriate to the hunt.
