
All bitches will loose their coat, I just find my bitches keep better condition while regrowing coat (which takes a lot of nutrition), if kept on a higher nutrient dense diet, but then my breeds maintenance amounts are rather less than is recommended for their size, so maybe that has a bearing.
My adult girls only get about 6 ounces of complete food and are between 18 - 20kg adult bodyweight. My friends Border Collies similar weight and size need at least half as much food again for normal maintenance, often twice as much.
Of course as I want to continue showing my girls I want to keep/regain optimum condition. Breedign a litter will take a bitch out of circulation for around 8 months (season, pregnancy, rearing and then at least 4 months from whelping, but more like 6 before they are remotely showable) anyway.