There are many different kinds of animals that eat ferns, including white-tailed deer, rabbits and insects such as caterpillars. Not all animals can eat ferns because some are toxic to animals, such as the bracken fern, which is highly toxic to horses and pigs as well as cattle.
It is important for horse owners and pig owners to determine what type of ferns are around their home to ensure that the animals are not exposed to dangerously toxic ferns. The reason for the fern's toxicity with some animals is because some ferns contain thiaminase and ptaquiloside, which damage the bone marrow in the animals and cause hematuria and anemia.
