Frequently (and not so frequently) Asked Questions
BRIEF: Can horse nettle poison the meat of beef cattle?
QUESTION:
I finally did get a plant sample, and it definitely is horse nettle. Can
sub-lethal doses poison the meat of beef cattle and how much, if at all, is
tolerable in the forage?
ANSWER:
I don't think there is any danger of passing enough solanidine (or other
solanaceous steroidal glycoalkaloid) through the meat or milk to harm people
eating these products. These toxins are very poorly absorbed, are torn to shreds
by the rumen and what is absorbed is metabolized and excreted very fast. Humans
and livestock can be poisoned directly with GI symptoms, nervous disorders and
possibly birth defects, but it takes a lot of material. I don't think there is
no way that the meat of even a symptomatic cow would harm a human, much less
that of an animal eating a sub-toxic dose. I have not done the specific
experiments to prove this, and they might be worthwhile to do, but we eat more
of these compounds than one is likely to find in the meat all of the time.
On the other hand, one can't rule out rare, idiosyncratic allergic effects of
small amounts, but I have never heard of any.
Most people can tolerate quite a bit of these toxins, and they impart flavor to
tomatoes and potatoes that we value. I have experience feeding these crop by
products and Cheeke's book has a good couple of pages on the subject (pp154-156
in Natural Toxicants in Feeds, Forages and Poisonous Plants Cheeke 1998).
Have their stock shown any symptoms clearly related to eating horse nettle?