Why do pets eat grass?

Why do pets eat grass? Does it mean they are sick?

This is a question vets are often asked because grass eating is common among both cats and dogs.

We expect dogs and cats to eat meat only. They’re carnivores, right? Actually, dogs can eat more non meat-based foodstuffs than we expect. They can digest carbohydrates, fruit, and vegetables.

A recent study found up to 45% of dogs enjoyed eating grass yet fewer than 10%  throw up afterwards, which means that many dogs eat grass without apparent underlying health issues.

When grass eating isn’t good

Sometimes grass eating can indicate gastro-intestinal problems like gastroenteritis (runny tummy), internal parasites such as worms, tummy pain and a dramatic lack in nutrients. Which means that if you do find your dog vomiting after eating grass, it is best to have him or her checked over by your vet, especially if it happens often.

Plant eating isn’t limited to grass. Many pets enjoy chewing on a variety of plants including ground covers, creepers and bushes. It’s essential that you make sure the plants in your garden are pet-friendly, as there are some plants that can be deadly to pets.  These include latex producing plants, cycads, oleanders, and azaleas. Some grasses may also have very sharp leaves and are not suited for grazing dogs. Rather stick to the softer varieties of grasses.

But what about cats?

Cats, like dogs, like to eat grass. Up to 79% of cats in one study were observed eating grass with very few showing signs of vomiting. This has also been seen in wild cats. However, there’s a common belief that this habit helps them vomit and more veterinary studies suggest a variety of reasons for cats eating grass, including:

• Stomach upsets (hairballs, constipation).  As cats lack the enzymes to digest grass, you will most likely see it undigested in the stool or vomit.

• Parasites. With improvements in deworming medication and more cats being dewormed regularly, parasite control does not seem to be a big factor anymore.

• Stress. Cats display a host of behaviours when they are stressed and eating grass and other strange things is one of them. Stress is often under appreciated as a problem in cats, but it is a very serious problem. So, if grass eating is accompanied by inappropriate elimination (weeing in strange places), recurrent urinary tract infections, overgrooming or self-trauma, it should always be viewed as important and needs veterinary evaluation.

• Diet. For a long time, grass eating was considered a sign of a diet deficient in certain micronutrients. However, grass eating habits do not differ much between cats fed good vs. bad diets and with the many well-balanced diets available today, cats are generally eating better quality food anyway so this may not be considered an important reason for grass eating.

As a cat owner, your best bet is to observe your feline friend when he/she is eating grass. If there is vomiting or there are other stress behaviours then please see your vet.

Article by Dr Morné de Wet, Cottage Vet


Department of Health COVID-19 updates available at www.sacoronavirus.co.za


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