Wild thistles provide healthy benefits for house rabbits and other herbivores

Wild thistles provide healthy benefits for house rabbits and other herbivores
Milk thistle is a nutritional and medicinal 'weed'

Wild thistles are nutritional and medicinal

When you think thistle, you may think of the common bull thistle, a spiny sort of wild plant with a large purple flower and the national flower of Scotland. Tastier and tenderer than bull thistle, the leaves and stems of milk thistle and sow thistle (or hare thistle) are similar in appearance to the bull thistle, with the most noticeable difference being the appearance of their flowers. Sow thistle can be distinguished by the multiple small, yellow flowers that bloom from spring to fall; milk thistle has small purplish pink flowers which bloom in spring and blotchy white veins and patches on the surface of its leaves.

Favorites of both wild and house rabbits

The name sow thistle, or hare thistle, refers to the plant’s attractiveness to these and other animals, while milk thistle has a milky white ‘sap’. The leaves of these plants are quite tasty for human consumptions as well, being used in salads and other dishes much like dandelion or spinach greens. The stems can also be peeled and then steamed or used in stir-fry dishes.

As both of these wild plants are considered ‘weeds’, they are easily grown but will spread around your (and your neighbor’s) property. If you know of a field or empty lot in Dayton where no chemicals are used, these plants can be easily found and harvested from now until the first hard freeze.

Both thistle types are high in fiber, B vitamins as well as vitamins A and C, and contain calcium, phosphorus and iron. Both thistle types are high in fiber, a critical element in the diet of both small pets and their human keepers!

Much research has been conducted on the medicinal effects of milk thistle; silymarin is a powerful antioxidant which naturally occurs in milk thistle. Silymarin protects the liver, reduces inflammation, and blocks toxins; the nutraceutical components in milk thistle have been found to be many times more potent in antioxidant activity than Vitamin E.
Milk thistle also contains omega-6 fatty acids, which have anti-inflammatory properties and promote skin, hair and bone health.

Bunnies and endotoxins

A diet low in fiber is associated with increased levels of the type of gut bacteria that produce endotoxins; endotoxins contribute to gassiness of the bowel, and gassiness helps set bunnies up for potentially fatal GI stasis. One of the liver’s jobs is to filter out the bacterial endotoxins; if the liver has already been compromised in some way, the liver can be overwhelmed and unable to perform its filtration task.

The silymarin in milk thistle was shown to protect against liver damage from a variety of toxins, in a variety of animals; silymarin even stimulated the liver to make new liver cells to replace the damaged old cells!

Studies in pigeons

Data collected in milk thistle studies in pigeons has been positive, and there have been numerous anecdotal accounts from bird owners on the positive effects of milk thistle. Parrot owners have reported that their pets’ health improved dramatically with the introduction of milk thistle into their diets after treatment of hepatic lipidosis, or fatty liver disease, a disorder highly prevalent in captive parrots.

No one is suggesting you eschew proper veterinary treatment of your pets, but milk thistle can be an effective tonic as well as a preventative treatment for various ailments of small pets.

For commercial milk thistle products, the suggested doses range from 50-250 mg/day; birds received 100-150 mg/kg every 8-12 hours in the aforementioned studies.

Low toxicity

Milk thistle has a very low toxicity – at least one study dosed cats with 5 mg/kg and no toxic effects were observed, an important finding as cats are more prone to liver problems from medication and other compounds because of their specialized liver processes.

Commercial milk thistle

Your average house rabbit or other herbivore will greatly enjoy fresh thistle, but in the dead of winter or if recommended by your exotics veterinarian, it may be preferable to purchase commercial milk thistle products. Olympia Health Foods in Kettering (behind Town & Country shopping Center) can help you choose the right thistle product. Some things to keep in mind, regardless of where you shop or what nutraceutical you are purchasing:

  • Look for a label on the product that says: ‘Meets USP Specifications for Potency, Uniformity and Disintegration, Where Applicable’
  • Find out if the company manufacturing the supplements follows Good Manufacturing Practices for drug grade and not food grade standards (the internet can help with this)
  • See if the manufacturer is regulated by a governmental agency

Side Effects

Milk thistle may act as a mild laxative for the first few days, so start with smaller doses/quantities until your bunny or other small pet gets used to the addition to their diet.

Milk thistle and deathcap mushrooms

Interestingly, milk thistle has proven to be 100% effective in preventing the toxicity of this mushroom, a fungus which causes death in roughly a third of those who ingest it. If given within ten minutes of mushroom ingestion, the toxic effects were completely reversed, and if given within 24 hours, the thistle prevented death and greatly reduced the amount of liver damage, according to the University of Maryland Medical Center.


For more information:

University of Maryland Medical Center

University of Michigan



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