why do dogs eat grass?

I noticed Penny eating grass in the garden today and it occurred to me it's lucky our garden has weeds.

The clump of grass included some panic veldt grass (ehrharta erecta) and what I think is prairie grass (bromus unioloides).

When I looked at a few sites to check out what types of grasses dogs usually eat, I came across an Australian article by Justin Huntsdale about Sam Bjone, who is studying the eating of grass by dogs - this was accompanied by a photo of dogs eating kikuyu (pennisetum clandestinum).

Green Foods has a report on this study also. Interestingly, they say they are excitedly awating the results because

We at Green Foods believe that dogs and many other carnivores, including cats and bears, eat cereal grasses because cereal grasses contain nutrients not found in meat that are essential for the animals' good health.

Of course, this raises the great debate about store-bought dry food, which is often criticised by raw feeders and barf (bones and raw food/ biologically appropriate raw food) feeders, who say that canines don't naturally eat cereals.

One organic site suggests that eating grass occurs because wild dogs would eat the entire body of their prey and this would include the stomach contents of a grass-eating animal. The author recommends growing rye or barley sprouts (not wheat sprouts) and including these in the daily diet. I can see that this might be useful but I'd want to cross-reference it with other authorities before I did it. After all, as long as I make sure our garden includes weedy varities of grass (not too hard to arrange!) Penny can choose the amount and type of grass she eats.



April Holladay, at WonderQuest (Solving Mysteries People Wonder About) , discusses the various theories briefly . She says

Finally, dogs may appear to eat grass, says Feiler, when they are just running the blades through their mouth to gather information. Their sense of smell and taste may act together to detect if other animals have walked through their area or urinated on the grass.

I must say, I enjoyed the cynical discussion of commercial supplements that are designed to enhance an apartment-dwelling dog's diet. I laughed out loud at the last sentence. Suffice it to say that Penny loves visiting a friend of mine who has lots of cats. Penny zeroes in on the kitty litter tray to check for enticing feline poo.

She also races out each morning to check the garden for possum poo. So, if I move to an apartment I just could be a customer for an intriguing type of dog-food supplement...