Traditionally, anything containing less than 20% NFE carbs on a dry matter basis has been considered low carb but now, with the increased popularity of raw foods which tend to have much lower carb levels, the bar is shifting.
Dogs need both omega-6 and omega-3 fatty acids from their diet but the ideal amounts and ratio of the two is still a matter of some discussion. It is clear that if the ratio of omega 6 : omega 3 is too high, it can cause increased inflammation so, for many dogs, the lower the ratio the better.
No ratio or feeding regime is best for all dogs. Just like us, some do better on one kind of diet while others will do better on another. All we can do is try the foods out and see how the individual dog does. You can find more info on our feeding guide.
I know some pet owners that stick rigidly to a set number of calories per day but they are a small minority. I always recommend starting out with the manufacturer’s suggested feeding amounts and then adjusting depending on how the dog’s weight responds. More info again in the guide.