Sorry if I created a panic.  The amount of toxin found in onion powder that
is put in baby food is probably very small and probably won't cause severe
problems in most animals, but it can't hurt to be careful (as there have
been some cases, though few, in other small animals).  Most cases of onion
toxicities occur from animals eating raw or cooked onions.  For the most
part, animals in general find onions quite palatable.  Some animals are more
resistant to toxicity than others.  Who knows where ferrets fall in, but
they probably would be somewhere between the dog and cat, which are more on
the susceptible end.
 
Gets rather scientific from here on down:
 
I am by no means a toxicology expert.  Please take what information I give
with a grain of salt :) If you have any concerns consult your veterinarian.
 
Onion, garlic, chives, etc.  belong to the species Allium (Alliaceae) in the
family Liliaceae.  There are over 400 species of Allium (too many to
count!).  All plants in this species have a characteristic onion odor.
Toxic parts of the plant include the bulb, bulblets, flowers and stem
(pretty much the entire plant).  The toxic principles include
N-propylsulfide, propenyldisulfides, methyldisulfide, allyldisulfide (there
are probably others as well).  The propenyldisulfides have been implicated
as the toxin that causes the hemolytic anemia associated with Heinz body
formation.  Other problems associated with plants in the onion family are
contact dermatitis and gastroenteritis.
 
About Aloe.  While I was researching onion toxicities, I also wandered into
the aloe section of the toxicology book.  I remember someone way back when
asked about aloe and I can't remember who it was.  It seems that aloe mainly
acts as a cathartic and causes diarrhea.  However, it has been found
experimentally that extremely high doses (extremely unlikely that a ferret
could or would eat that much) cause nephritis (inflammation of the nephrons
in the kidney) in rabbits, which could lead to renal failure.  Aloe has also
been known on rare occaision to cause a contact dermatitis.
 
                                Lisa
 
Special contributions from Squirt who always tries to help me with whatever
I'm doing and likes to get my adrenalin going on occaision, too.
[Posted in FML issue 1601]