On Tue, 23 Apr 2002 21:17:13 +0900, Tom Bridgeland
<[log in to unmask]> wrote:

>..., but I wonder, how are domestic animals
>that eat grass their whole lives, then fattened on grain any different
>from a deer that fattens on my Dad's corn (a grass) before I eat it in
>the winter?

Such deer fattened on ordinary crops are certainly only marginally
different from other agricultural animals, like a cow.
The big difference is the speed they are growing.
Grain seeds are the same or similar plants as grass.

But the grain seeds (the corn) are very much more *dense* than
the grass. 600g grain are worth 4-8 kg of vegetables (grass).
The animals manage to eat a lot  more of energy (and protein) in less time
to the pleasure of the farmer. May it be deer or cow.

In the fat then you find the difference reflected.
The load of carbs are converted into SFA and MUFA.
This is the reason why (fed) domestic animals have som much SFA and MUFA
and so little MUFA.
Wild animals and plants nearly everythink you can get, has a PUFA part
of some 25-35%. Farm animals don't.
And the PUFA come from the plants eaten.
If the animals eat Herbs they get 1) a lot and 2) a good w-3/w-6 ratio of
PUFA fats. If they eat predominately grains, there's much more w-6 in it.

>Or for that matter a wild paleolitic ox killed with a
>flint tipped spear 20,000 years ago in the fall, after fattening on
>ripe wild grass and legume seeds?

The difference is the speed they grow and on what they grew.
Just look at the overall fat percentages of "wild unugulates" (Speth, cited
by L.Cordaine). 4 %. That's little and the fat is good.
Likewise slow growing farm animals (like african zebu) are similarly much
better. But that's not for the cheap market and not for masses of people.

Flint tipped spear is better.

Amadeus