> wrote
> The main point of veganism is to boycott factory-farming, which causes
> animals to lead miserable lives.

That's a lie, vegans boycott ALL forms of animal products,
not only "factory farmed" meat.

> The animals who live on factory farms have to be fed with plant
> products, the production of which will cause the death of wildlife.

That's true, but meat can be obtained that requires little or
no plant supplementation. Vegans oppose all of it. And the
implication of that position is that it's "plant production" at
the root of much of the animal killing in agriculture, a fact
which confounds the moral presumptions of veganism.

> Animal products are an inefficient use of land,

That depends on the land. A lot of land is not very arable
but ideal for pasture.

> so their production
> will cause more death of wildlife than the production of plant products
> to be fed directly to human beings.

Not using non-arable land as pasture and grasses and raw
grains as the foundation of the human food chain would mean
a lot more intensive, (i.e. "factory") farming of plants.

> As for the argument that ruminant-pasture food production causes fewer
> deaths than some forms of plant food production, the following article
> is worth a look:
>
> http://courses.ats.rochester.edu/nob...least-harm.pdf

It's worth a look but not much more, it's full of fallacies,
diversionary arguments and unsupported assertions.

Vegetarian diets are quite good, and efficient, where vegans
go awry is falling for all the feelgood quasi-political nonsense.