The first thing I will say is that you must take your dog to be checked out by a vet. While not wishing to alarm you, this breed does have a tendency to develop heart disease and if she is becoming tired more easily that could be a warning sign. Having said that, carrying excess weight can also cause a dog to become lethargic and listless. The breed standard weights are between 5-8 Kg so your dog is very overweight and really needs to lose some of those excess pounds. I think that your dog really should be on a prescription weight loss product that will help reduce her weight more effectively. Most light diets are only really suitable for dogs that have a tendency to become overweight and are not formulated to produce weight loss to the extent that is required here. Your vet can advise you about those diets too. There are several different makes to choose from. Hills have recently reformulated their weight loss product and studies show that it is possible for overweight dogs to lose 22% of their body fat within 2 months. Please do take your dog to the vet. You are doing really well with the exercise but I really think some extra support and advice is needed now. Do let me know how you get on.
By Libby Sheridan (Hills Pet Nutrition) (Professional Advisor)