If there’s a significant difference in kcal. per cup then yes, you should adjust the portion sizes accordingly. The easiest way to do this would be to figure out how many kcal. your dog is currently eating and when you switch to a new food divide the number of kcal. your dog eats to maintain optimum body condition by the kcal. per cup in the new food to determine how many cups of the new food you need to feed. I’d only do this if the differences are big. So if you’re feeding a food that has, say, 410 kcal. per cup and switch to a food with 425 kcal. per cup the difference is so small that you shouldn’t need to adjust the portions. On the other hand, if you’re feeding a food with 380 kcal. per cup and switch to a food with 480 kcal. per cup, some adjustments will need to be made.
