my youngest girl is 26 months old and is heading for her 3rd season, she is a very slim petite girl of large breed, but i have noticed that a few weeks before her season she goes very loose and drops her weight looking very thin, i just wondered if anyone else had this problem , thanks

I believe this could be quite normal. Racing Greyhounds and other physically hard working bitches are known to perform better just before coming into season.The normal slight weight loss at this time can usually be seen in slimly built bitches with fine coats. Maybe the weight loss is part of the process to prepare a bitch to be at her peak before mating.