Why do dogs eat grass?
This canine phenomenon is not only a mystery to dog owners, but also to researchers. The fact is that 90% of all dogs eat grass on occasion. Popular folklore however offers several explanations for this behaviour, such as: “Dogs eat grass to to induce vomiting” or “It could be an indication of insufficient minerals or vitamins in the diet“
But which of these theories is true?
According to a recent study by SJ Bjone at the University of New England in Australia of a total of 1399 dogs that ate grass only six dogs vomited afterwards. This is supported by numerous other studies in which researchers and veterinarians have been devoted to this topic.
It can therefore be assumed that eating grass does not serve as an emetic in dogs.
Furthermore, extensive observations and tests have shown that grass-eating behaviour is found in both wolves and dogs and that this behaviour can be assumed to have persisted despite the domestication of dogs. It is therefore innate, with the eating habits of the mother dog reinforcing the eating habits of her puppy. A particularly striking fact was that, regardless of weather and breed, young plants, grasses and corn plants were preferred. If your pooch shows pronounced vegetarian tendencies, please take special care with toxic plants such as ivy, vine tomatoes, rhubarb, onions, boxwood, jasmine, wisteria, laburnum, clematis, oleander and daffodils.
Vitamin or dietary fibre deficiency?
This theory is also extremely persistent, but was refuted in the above-mentioned studies, as it would require regular intake of grass by the dog in this case. Most dogs only eat grass on a very irregular basis, so the theory of vitamin deficiency could not be corroborated. Moreover, even dogs that are fed a balanced diet eat grass and the intake is too low to offset any deficiency.
As previously stated, the wild relatives of our dogs such as wolves, coyotes and jackals are in fact not purely carnivores. Depending on the environment in which they are found they most probably also enjoy a vegetable diet. In conclusion, it seems that dogs eat grass as a relic of species-specific dietary patterns, which only appear so strange to us humans because we often see the dog as a pure carnivore.