Is watercress safe for my cat?

Question.
I have a pond with a few goldfish. It has a pump and biological filter box that runs constantly, and a vegetable filter, which consists of a flourishing bed of watercress. No chemicals are used and it's very clean and well maintained. I believe it's good for animals so would it be safe to add this watercress to my cat’s food?

Answer.
Watercress contains Vitamins A, B1, B2, C and E, antioxidants and minerals including iodine, iron salts, calcium phosphates, potash, sulphur and manganese. It contains four times as much Vitamin C by weight as lettuce and more calcium than whole milk. It is a nutritious food and could be regarded as a plant vitamin and mineral supplement. It is a traditional spring tonic and 'blood-cleanser'. Watercress is thought to stimulate the appetite, relieve indigestion, increase the flow of urine and help in chronic bronchitis with excessive mucus production.

Its hot flavour indicates its generally 'stimulating' action on the body. Indeed, the ancient Persians gave it to their children for sound growth. There is a problem with watercress that grows in water where sheep graze as it can become contaminated with worm eggs. It is therefore important that watercress comes from a clean source. You may find that only a small amount would be palatable to a cat. It may be more appropriate to allow your cats to graze the watercress themselves, if they wish to. Cats will graze fresh plants if given the opportunity, apparently for nutritional reasons, and not just couch grass which they use to make themselves sick. Their need for fresh raw living foods is not met by processed cat food.

 _{source Your Cat Mag.}