haha It's nothing exciting guys. I have raw fed my dogs for around 20 years, mostly whole prey (whole rabbits, pheasant, hare, squirrel, hens etc). I'm due in for more kidney surgery in a couple of weeks and not in great health, so I've been looking around at the newer generation of 80/20 (80% meat, 20% veg, fruit and botanicals) dry foods. They're not as good as raw feeding but they're the 'next best thing' until I'm back on my feet. Not really practical or fair to expect randomers helping out to gut rabbits and handle dead chickens when they're feeding the mutts for me.
As one of our dogs is presently a puppy, I was looking into the three brands and noticed the brand I'd bought from recommended half the calories per day for my pup than did anyone else. Now we can't compare grams per day of food, as 200g of Food A could be as nutritionally dense and more bioavailable than 400g of Food B. Kilocalorie requirement overall, however, would be expected to be the same for a given animal, and only the delivery method to differ.
As such I emailed the three companies and asked for clarification. Generally calorie requirements are worked out as Resting Energy Requirement (RER) or Metabolic Energy Requirement (MER). For example RER = ((30 * aKG) + 70) * b.c or else 70(xKG)^0.75 * y where the KG value is the dog's weight and for puppies the * b.c is the RER multiplied by a value based on their age (for example 2.5 or 3.0). Most companies fell within the values expected but the company who were so... sensitive... in their replies are recommending literally half the calories per day of not only any other company but also of the output of any given formula for calculating calorific need.
If I wasn't going into hospital, it wouldn't matter so much. I'm a highly experience dog owner, trainer, worker and breeder and can go by 'eye' as to development. Left with well intentioned family/friends, if they stuck to the half-the-calories-of-everyone-else regime and it turned out to be too little, nobody would be the wiser until I came home and found my pup with damaged growth plates and knackered hips for his future development.
I shall refrain from posting all the emails as I don't see much point, but I hope this helps clarify things for those interested.