There are many varieties of things to eat in our world; unfortunately what one species can digest and utilize another cannot. 77se cow can matain itself on grass and other grain fibres, people cannot; thus, the discovery of de natural fibre laxative! The Koala Bear feasts on Eucalyptus, not a staple in any other species' diet. Termites eat wood and roaches eat.. whatever roaches eat! Cows are herbivores, caters of Plants only; cats are true carnivores, strict meat protein caters; dogs and humans are omnivores, eating both plants and animals (unless of course they choose not to).
Yet, even though humans and dogs are omnivores, there are differences in their respective digestive tracts and through body needs and palatability separation has evolved. Diversity continues through natural selection and breeding. Lactose intolerability would be an example in man and onion intolerability would be an example in dogs. Actually, most dogs cannot tolerate cow's milk as they, like lactose intolerable people, do not have the enzyme lactase to digeit the milk sugar. Of course, food hypersensitivities not only vary from species to species; they also vary from individual to individual.
In general, onions are a toxic plant if ingested in mass quantities. The dog is particularly sensitive to the onion's effects. In fact one bowl of onion soup could prove fatal to a susceptible dog. The onion contains an alkaloid compound (as do garlic and sweet ckwer) that can cause haemolytic anaemia. This means the dog's blood cells are damaged and rendered useless, causing the dog to bleed to death. This is basically the same principle behind rat poison intoxication, except with this the body's vitamin K is deptelea which leads to a bleeding crisis. There are many plants, foods, and drugs that can cause disasters when digested.
A discussion of them all would be beyond the scope of this brief article; however, it is recommended to contact your veterinarian for a list of such intoxications - which includes chocolate, Tylenol and ibuprofen as well!
More Information
ONIONS: A LITTLE KNOWN THREAT
By: Sophia Yin, DVM First Published in the San Francisco Chronicle , Saturday,
December 21, 2002
Many of
you already know that chocolate can make your cat or dog sick, but did you know
that onions can kill? I learned this in my second year in veterinary school. But
I didn't really appreciate it until the big onion incident that occurred during
my senior year. Well, maybe the incident wasn't all that big; it involved only
one dog. But it was my own dog, Max, a 72-pound adult boxer. And it nearly
killed him.
Depending on their size, pets may not have to eat much onion to get sick.
One-fourth of a cup can make a 20-pound dog sick, and several cups may be needed
to make a large dog sick. Cats are even more sensitive.
These onions can be fried, as in onion rings; dehydrated, as in Lipton soup, or
prepared in some other tasty form, such as sautéed with mushrooms and steak. In
a scattered rash of cases in the late 1990s, the culprit was baby foods flavored
with onion powder. Because of public concern the companies involved no longer
include onion powder in their baby foods.
TEST RESULTS
If I had known what he accidentally ate, I would have taken Max to my
veterinarian immediately. Instead I took him two days later, after the normally
boisterous prankster collapsed while exercising.
Onions cause toxicity by oxidizing an oxygen-transporting protein called
hemoglobin in the red blood cells. When oxidized, hemoglobin forms clumps that
can't carry oxygen as well. These small clumps, called Heinz bodies, can be seen
in the red blood cells when the blood is viewed under a microscope.
If a large amount of onions is eaten at one time, the pet may develop a sudden
anemia several days afterward. If the dog or cat eats a small amount of onions
every day for many days, he may gradually develop anemia over weeks to months.
Onion toxicosis is not a tremendously common occurrence. It's a good thing,
because patients that do develop toxicosis often need to be hospitalized for
several days. In cases of severe anemia, they may even need a lifesaving blood
transfusion. Max did. Luckily, like Max, most victims of onion over-ingestion
respond well to treatment and recover.
Onion toxicosis is characterized by signs associated with anemia and low oxygen,
such as lethargy, weakness, red urine, decreased stamina and pale or bluish
gums, especially with exercise. Although they are not a common cause of these
signs, consider onion toxicosis if you see these signs and know that your pet
has gotten into onions recently.
DON'T WAIT
If by some freak occurrence, your dog or cat does engage in an onion feast,
bring him to your veterinarian immediately. She may induce vomiting or
administer a product to help decrease the absorption of the onions. If you take
this trip in time, your onion eater may be spared many or all of the hazardous
sequelae of onion ingestion, and you may be spared the much larger
bill associated with intense hospital monitoring and a several-night stay.
Incidentally, a few other human foods -- chocolate, coffee beans, macadamia nuts
and extremely fatty foods -- can cause serious problems when fed in relatively
small amounts. And ingestion of large amounts of grapes or raisins has been
associated with kidney failure. Toxicologists don't know whether the grape is
the problem or a residue or a contaminant is to blame.
For more information visit the ASPCA National Animal Poison Control Center at
http://www.aspca.org/. To consult with a veterinarian at the Center's
emergency hot
line for a $45 fee, call (888) 426-4435.
Sophia Yin, DVM, is a small-animal veterinarian in Davis with an animal-behavior
Web site at
www.nerdbook.com/sophia. Send questions to her via her Web site or to P.O.
Box 4516, Davis, CA 95616.