Dr. Johns ingredients:- Cereals (minimum 4% rice), meat and animal derivatives (minimum 14% chicken), oils and fats, milk and milk derivatives, yeast, mixed herbs (900 mg/kg) minerals, molluscs and crustaceans (100 mg/kg). (25% protein, 15% oils)

CSJ Rocket Fuel: Chicken Meat Meal, Wheat, Maize, Unmolassed Beet Pulp, Chicken Fat, Chicken Liver, Wheat Feed, Salmon Oil, Full Fat Linseed, Prairie Meal, Yeast Extract, EC permitted natural anti-oxidants, Vitamin C and Rosemary Extract. (Protein 30%, oil 14%)

Skinners Field & trial Duck & Rice: Whole rice (40%), duck meat meal (20%), naked
oats, peas, whole linseed, sunflower oil, beet pulp, vitamins and minerals. (22% protein, 11% oils)

Skinners Superior: Poultry meat meal, maize, chicken fat, white rice,
whole dried egg, beet pulp, yeast, vitamins and minerals. (30% protein, 20% oil)


Depending on your needs, whether or not your dogs have a gluten sensitivity, how much exercise they get etc.
I'd give Chudleys a miss, it's not known for being good quality and Dr Johns seems to be on par with something like Pedigree. Its ingredients list is awfully vague.

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The biggest obstacle in dog training is the realisation that the majority of dogs are much smarter than people.