> because dogs eat a lot.

Uncooked meat does not have near as many digestible calories density wise as cooked grains. Of course it would be a lot harder for them to become overweight, but the food cost would be tremendous. Remember that obligate carnivores that weigh a lot, like tigers, are incredibly expensive to feed.

> Uncooked meat does not have near as many digestible calories density wise as cooked grains

That seems very unlikely, what with fat and the lipids in cell walls - got a source?

"Our observation that mice fed cooked meat retained higher body mass despite lesser intake (fresh- or dry- weight basis) indicates that cooking increases the energy extracted per gram of meat fed. This finding contrasts with the predictions of conventional nutritional assays, which on the basis of the Atwater system, return roughly equivalent metabolizable energy densities for raw and cooked meat on a dry-weight basis (Table S1). The problem with the Atwater system is that it ignores changes in di- gestibility, costs of digestion, and costs of immune defense, all of which are likely influenced by food processing. The result is nu- tritional inaccuracy. For example, cooking is known to increase the proportion of starch digested at the terminal ileum before access by most gut bacteria (2). Starch that resists digestion in the small intestine delivers only a proportion of its metabolizable energy to the consumer, because the short-chain fatty acids produced during bacterial fermentation of starch generate less ATP than the glu- cose produced by starch hydrolysis in the small intestine. Addi- tionally, the fatty acids are consumed as fuel for gut bacteria, and there are further losses from the production of combustible gases (40–42). Cooking, thus, increases the energetic value of starch to an extent greater than is represented by the Atwater system. Such differences between the calorie values determined by the Atwater system and the physiological outcomes observed in this study are relevant for the manipulation of diets to increased or decreased caloric loading."

* Energetic consequences of thermal and nonthermal food processing Carmody, R. N., Weintraub, G. S., Wrangham, R. W., Proceedings of the National Academy of Sciences2011 / 11 Vol. 108; Iss. 48

* https://booksc.org/book/37997813/2fc522

Note that the 'Atwater' system is referring to the traditional method used to determine caloric content created in the 1890s which burns food and measures the heat obtained from it.

Here is an interesting article about this issue:

* https://www.economist.com/1843/2019/02/28/death-of-the-calor...

I apologize for the single source -- I believed that the science was far more settled on this issue than it appears to be. Regardless, I hope it proves informative for further research if you decide to pursue it.

> Most wild dogs would eat almost exclusively fresh raw meat

Is that right? I understood most wild dogs eat a fair proportion of roots/berries and other herby stuff. A quick dig around:

"Unlike cats, dogs aren’t obligate carnivores. They can and do eat vegetable matter. Wild dogs will search for rotten fruit and will eat the semi-digested contents of their prey’s stomach. Some will dig up vegetables and eat grasses and herbs"

https://honeysrealdogfood.com/in-the-wild/

I'm not sure where that data is sourced from... Notice it's on the website of a dog food company, who I suspect has an incentive to tell owners that the veg in the dog food is 'natural'.

I suspect if dogs do eat vegetables in the wild, it's only if they can't get enough meat, since their domestication has made them less good hunters. Their wild counterparts, grey wolves, don't seem to ever eat vegetation (except when sick).

Fair enough but I've heard this (wild dog herbivory) from several sources. I can't find better, sorry.

wolves in the wild's diets are usually around 40% plants but of course that can vary widely from area to area. I'm sure wild dogs are pretty similar

Well, the coyote poop around here often has a lot of of berries in it.

And our dogs will actively eat grass sometimes, but that's probably more about upset stomachs.