Can cats eat onion?
Our cats are quite selective animals that do not eat anything that they have within their reach or that we generally offer them.
However, they can ingest foods for human consumption that are toxic to their organisms due to certain compounds in their composition. Some of these foods are grapes, raisins, chocolate, citrus fruits, the bones of some seeds, garlic and onions, among others. Some foods are more dangerous than others and the severity will depend on the amount of the food in question that they eat. Onion is one of the most toxic foods in cats, because it contains substances that act on feline red blood cells, destroying them and producing hemolytic anemia.
Is onion toxic to cats?
Yes, onions are toxic to cats . The onion or Allium cepa is a biennial herbaceous plant that belongs to the Allium genus and the Amaryllidaceae family. Other vegetables such as garlic, leeks or chives are also included in this genus. It is a very old plant, existing since the Sumerians in 6000 BC and whose origin is established in Pakistan and Iran.
The onion is a low-calorie vegetable that contains a lot of fiber and high amounts of calcium, potassium and vitamins. Its quercetin content stands out for its value as an antioxidant and its rich amounts of sulfur. However, it also has some toxic substances that are disulfide alkaloids, which target the red blood cells of cats. Specifically, what they do is:
Decrease the activity of the enzyme glucose-6-phosphate dehydrogenase , which is responsible for preventing the oxidation of red blood cells.
Due to this, the antioxidant defenses of red blood cells are reduced and destroyed, forming Heinz bodies and leading to hemolytic anemia (anemia due to rupture or destruction of red blood cells). Do not hesitate to take a look at these other articles on Anemia in cats: symptoms and treatment or Types of anemia in cats to learn more about the subject.
How much onion can a cat eat?
Our cats cannot eat onions , not even a small piece due to the reduced safety margin since only 5 grams per kg of weight are enough for our cat’s red blood cells to begin to suffer the consequences of oxidation and are destroyed , reducing the hematocrit (percentage of red blood cells of the total blood) of our cats and the appearance of clinical signs that can compromise the life of our little feline.
Bearing this in mind, smaller cats or those that weigh less have a higher risk of poisoning than a large and heavier cat, but that cannot in any case be a reason for confidence when offering them onions.
In addition, it does not matter if the onion is cooked or we give it to them raw, these alkaloids are not denatured or inactivated by cooking, so we should never give our cats onions , nor any food that contains it as an ingredient.
Symptoms of onion poisoning
The symptoms caused by onion poisoning in cats are those derived from anemia due to a reduction in the number of red blood cells or hemolytic anemia due to their destruction. By reducing the number of red blood cells our cats will be weak because these are responsible for transmitting oxygen through hemoglobin, so clinical signs such as the following will appear:
- Increased heart rate or tachycardia
- Increased respiratory rate or tachypnea
- Soft spot
Breathing difficulty or dyspnea
- Pale or yellowish mucous membranes ( jaundice )
- dark colored urine
In addition, the consumption of onion in cats can also lead to digestive signs such as:
- Loss of appetite or anorexia
- Abdominal pain
What to do if my cat has eaten onion?
If your cat has ingested onion you must act quickly and, although the intoxication takes time to give rise to clinical signs, your cat’s body will be beginning to destroy the red blood cells. For this reason, do not trust yourself and go to your veterinary center , since it is essential that you perform a gastric emptying or induction of vomiting, as well as the use of substances that absorb or neutralize toxic substances such as activated carbon.
If we take the cat to the vet too late when the symptoms of intoxication have already established , blood and urine tests will be necessary in order to detect the severity of the condition and in some cases a blood transfusion will also be necessary, as well as fluid therapy. and medications to control digestive signs if any.