I would think that it would be better to take your vet's advice than a weight chart. It can get really upsetting to try to keep too close a chart on her weight. I've found, with the Newfs, that they don't follow any chart too closely. One month they are too thin, next one too tall, next one too heavy
. I think it depends on the individual dog. It's fun to know the weight only because we get asked daily, "he's HOW old? How much does he weigh? How big is he going to get? Are you going to ride him?"