Significant nutrient differences between wild prey animals and domesticated food animals.
Compared with wild prey animals, domesticated, commercially-fed animals have
- Less protein, more fat
- Poorly balanced fat
- Lower mineral and antioxidant content
The differences between domesticated food animals and prey animals are especially important for raw feeders, who are trying to mimic the ancestral diet. Even if one can feed the entire domesticated animal, including the nutrient-dense parts of the prey animal, such as the blood, plasma, tongue, pituitary, adrenals, prostate, brains, eyes, testes– just like the ancestral dog consuming an entire young deer – the nutrient content would not match the nutrient content of the wild prey. The differences would be large: domesticated animals have less protein, more fat (often with an unhealthy balance), fewer minerals and antioxidants.
Pastured and free-range animals, while better than feed-lot fed animals, still have more storage fat than wild animals, they are still fattened up. Due partially to the higher fat content, the mineral content of free-range meats, measured on caloric bases, are still lower than that of wild prey animals. (Hence Darwin adds supplements and specific fats)
More fat, less protein.
Wild prey animals: more calories from protein than fat
Domesticated animals: more calories from fat than protein
There are few fat prey animals in the wild. On the other hand, modern food animals are intentionally fattened up, often with low-cost grains. The more the animal weighs, the more money it’s worth. Table 3.1 shows a good example: a fat and protein comparison of wild duck (USDA defined as duck, wild, meat & skin, raw (refuse 40%: 38% bone, 2% handling loss)) and domesticated duck (duck, domesticated, meat and skin, raw (refuse: 28%, bone)), the only direct comparison of the same parts of wild and domesticated animals I could find using USDA data[i]. (Darwin uses only the lean parts of duck).
Domesticated duck has more than twice the fat and almost twice the number of calories per pound as wild duck. From a macronutrient point-of-view, they are two different animals.
Table 3.1. Differences between wild and domesticated duck, as fed
| protein | fat | kcal / lb | |
| Wild duck | 17.4% | 15.2% | 959 |
| Domesticated duck | 11.5% | 39.3% | 1836 |
Note: The amount and types of fat in prey animals varied considerably by time of year, the size, sex, health, and age of the prey, what the prey ate, presence of predators, and other factors.
Table 3.2 compares the protein content of wild and domesticated duck on grams per 1,000 bases, which is what a typical 50-pound housedog consumes per day. Fed wild duck, the dog consumes 85 grams of protein, still less than the 123 grams in the ancestral diet, but a lot more than the 29 grams in 1,000 kcal of domesticated duck.
Table 3.2. Wild and domesticated duck, grams of protein per 1,000 kcal
| Grams of protein | |
| Wild duck | 85 |
| Domesticated duck | 29 |
| NRC puppy minimum | 43.8 |
| NRC adult minimum | 25 |
A diet of whole domesticated duck does not contain enough protein for puppies and, in my opinion, for adults, and exceeds safe upper limits for fat for all dogs. As we’ll see below, the mineral content of a meal of domesticated duck is lacking as well, certainly when compared with wild duck.
All the other data I’ve seen, and I look at lots of data, confirm that wild animals are much leaner than domesticated animals. The USDA data include a comparison of wild and domesticated rabbits. While I’m not sure the USDA is testing the same parts of the rabbits, the difference in total fat content is certainly significant. Wild rabbit contains 21.8% protein and 2.3% fat; and domesticated rabbit contains 20.1% protein and 5.6% fat, more than twice the fat content of the I-need-to-run-to-save-my-life wild rabbit. Mice and other small prey were at least part, and sometimes a major part, of the ancestral diet. Mice are well studied; zoo biologists have examined the protein and fat content of almost 1,000 mice. The average of the mice studies is 58% protein, 23% fat on a dry matter basis: more calories from protein than fat.
The difference in the balance of fats between domesticated and wild prey animals.
Wild prey animals have a different balance of saturated, monounsaturated and polyunsaturated fats than domesticated animals of the same species. The differences are due to the sometimes dramatically different diets, and the sedentary nature of food animals.
Beef and ruminants: too much saturated fats, not enough polyunsaturated
Beef is very high in saturated fats, and low in polyunsaturated fats. In fact, a diet of just beef, even the fatty cuts of beef, does not meet minimum requirements for linoleic acid, an essential polyunsaturated fat. As table 3.3 shows, even the organ fats in domesticated ruminants are primarily saturated fats; in wild animals organs are usually higher in polyunsaturated fats than saturated fats[ii]. While many experts in fatty acids disagree on the value of saturated fats, whether they are healthy or not, my point is that – when feeding beef, lamb and venison foods – the saturated fats are out of balance.
Table 3.3. Percentage of fatty acids| SFAs | MUFAs | PUFAs | |
| Ground beef | 48 | 46 | 6 |
| Beef heart | 45 | 37 | 18 |
Poultry: too much omega-6s
As we saw with ducks, most commercially produced poultry, especially chickens, are much higher in fat than wild prey. While the overall balance of saturated and polyunsaturated fats in poultry is more in-line with the ancestral balance, there are far too many omega-6s and not enough omega-3s. Almost all fatty experts agree that high amounts of omega 6 and low amounts of omega 3 create a potentially very unhealthy situation (see chapter 4). Domesticated chickens, depending upon the parts fed, have 6 to 25 times more omega-6 than omega-3. Table 3.4 compares different chicken parts with the ancestral diet.
Table 3.4. Omega 6:3 ratios of various chicken parts, compared with ancestral diet
| Overall fat % | Omega-6 / Omega-3 | |
| Ancestral diet | 5.7% | 2:1 to 6:1 |
| Chicken breast meat, skin & separable fat removed | 1.2% | 6:1 |
| Chicken breast meat with skin and fat | 9.3% | 25:1 |
| Chicken leg, skin & separable fat removed | 3.8% | 9:1 |
| Chicken leg with skin | 12.1% | 22:1 |
| Chicken thighs, skin & separable fat removed | 3.9% | 10:1 |
| Chicken thighs, with skin | 15.3% | 25:1 |
| Chicken fat | 99% | 40:1 |
Lower mineral and antioxidant content
Prey animals have higher minerals contents than domesticated commercially-fed animals. This is primarily because domesticated animals are fed to lower mineral standards than the prey diet, with the exception, in most species, of zinc.
This is well illustrated by examining the mineral differences between domesticated ducks and wild ducks in table 3.5.
Table 3.5. Mineral content per 1,000 kcal. Meat and skin only; does not include bone and organs
| Mineral | Wild duck | Domesticated duck |
| Iron, mg | 9.7 | 5.9 |
| Zinc, mg | 3.6 | 3.4 |
| Copper, mg | 1.5 | 0.6 |
| Manganese, mg | 0.09 | 0.04 |
| Selenium, mcg | 60.7 | 30.7 |
Wild prey animals have greater amounts of antioxidants than domesticated animals, the limited data show. The polyunsaturated fats in the dog’s ancestral diet were well defended with ample amounts of vitamin E and other antioxidants; this makes sense – the dog’s prey probably ate nuts, seeds, and other vitamin E rich foods, much more so than present domesticated animals eat. For example, the ancestral diet had about 25 IU / kg as fed; domesticated duck has 10.5 IU / kg, less than ˝ the vitamin E content of the prey diet.
Domesticated animals eat what they are fed; rarely do they eat antioxidant-rich foods. On the other hands, wild animals may prefer antioxidant-rich foods, according to a recent study. Researchers from the University of Freiberg and the Max Plank Institute for Ornithology in Germany offered a group of blackcaps (a warbler) a choice of two foods. The foods were identical in all respects except for the amount of flavonoids they contained. The researchers found that the blackcaps actively selected the food with added flavonoids. As well as the food selection experiment, the study also looked at whether or not the flavonoids had an impact on the birds' health. They found that, compared with birds not fed the antioxidants, blackcaps that ate modest amounts of flavonoids for four weeks had stronger immune systems[iii].
[i] http://www.nal.usda.gov/fnic/foodcomp/search/
[ii] American Journal of Clinical Nutrition, Vol. 71, No. 3, 682-692, March 2000
Plant-animal subsistence ratios and macronutrient energy estimations in worldwide hunter-gatherer diets. Loren Cordain, Janette Brand Miller, S Boyd Eaton, Neil Mann, Susanne HA Holt and John D Speth
[iii] Wiley-Blackwell (2008, April 4). Feathered Friends Favor Fruity Flavonoids. Science Daily. Retrieved April 4, 2008, from http://www.sciencedaily.com /releases/2008/03080331223816.htm
