Cats are carnivores by nature. Cats’ teeth and intestines are adapted to feed exclusively on meat. The only plant-based food eaten by wild cats is produced in the intestines, with the exception of grass, which they rarely chew for its medicinal properties. Whereas the toxic substances in plants are always excreted in the liver (in rodents and birds), this liver function is not developed in cats.
The cat’s liver functions in such a way that it is unable to process toxic substances quickly. As a result, it is very common for cats to be poisoned by products that are ingested by other species without causing any harm to their bodies.
Domestic cats are much more loyal to their own tastes than their older relatives and are more likely to try a variety of fruit and vegetables at home. To avoid dangerous health consequences for cats, it is essential to know which human foods are life-threatening for cats. Some of the following foods are poisonous to cats when consumed even in small quantities, while others do not cause disease if not taken repeatedly or in large quantities.
Chocolate, cocoa. Chocolate contains theobromine, a substance that is highly toxic to cats. Theobromine increases heartbeat, causes arrhythmia and acts as a diuretic. A small amount of chocolate ingested initially causes increased activity, neurological syndrome (disorientation, etc.) and thirst in cats. Vomiting or diarrhoea may occur within a few hours. High levels of theobromine can cause a heart attack within 24 hours.
Coffee and tea. Coffee grounds, coffee beans and tea contain caffeine, a strong stimulant of brain and physical activity. Although some cats enjoy tea and coffee with milk, this can be dangerous. Caffeine always causes hyperactivity and high doses cause cardiovascular and nervous system diseases.
Vegetables
Onions and garlic. Onions contain a disulphide (N-propyl disulphide) which breaks downto cat erythrocytes, causing haemolytic anaemia. Onions are poisonous due to a number of properties: salty, dry, powdered or cooked. Cooked food containing onion or onion powder should not be given to pets as a treat. Garlic has a similar poisonous substance but in smaller quantities. Onion poisoning causes haemolytic anaemia, which results in the breakdown of erythrocytes and their free circulation in the body. The first signs appear a few days after eating onions: vomiting, diarrhoea, loss of appetite and lethargy.
Tomatoes. Tomatoes, like all other plants in the potato family, contain a bitter and poisonous alkaloid called glycoalkaloid solanine, which can cause severe gastrointestinal pain. In general, cats are reluctant to eat tomatoes, but there have been cases where the use of one small cherry tomato in a cat’s diet has resulted in its death. Not only mature tomatoes are poisonous to cats, but also green tomatoes, their leaves and stfor the lance. The toxins disappear during production, so the tomato juice in sardine or other fish boxes will not be dangerous.
Potatoes. Like tomatoes, potatoes belong to the same family as the potato family and contain an alkaloid. Salty or raw potatoes and their peelings are poison to cats. Prepared potatoes are not dangerous for cats but are completely useless as the cat’s intestines do not break down starch.
Fruits
Sunflower and fruit pits. Apple seeds contain up to 0,6 % of the glycoside amygdolin (hydrogen cyanide). The glycoside interferes with the blood’s ability to deliver acid to the tissues and causes shortness of breath.
Nuts
Many types of nuts are dangerous for cats because of their high phosphorus content, excess phosphorus in the body is undesirable. Walnuts are particularly toxic to cats.