From cognitive disorders and depression to cardiovascular disease, cancer, immune disorders, asthma, and more, fish-derived omega-3 fatty acids support many body systems. We know horses benefit from fish oil supplementation, and new research* shows that pain stemming from the cornea can also be improved with nutritional supplements containing omega-3s.
In the study*, researchers describe a condition called â€œneuropathic corneal painâ€ or NCP. Neuropathic pain refers to either a primary lesion or injury affecting the nervous system. In the case of NCP, the pain stems from the nerves of the cornea, the outermost layer of the eye, which is also the most richly innervated tissue in the body.
â€œThe corneas of horses are relatively thin and exposed to a wide range of environmental risks, making them prone to trauma and ulceration. Not surprisingly, corneal ulcers are one of the most common eye issues that equine veterinarians treat on a day-to-day basis,â€ said Laura Petroski, B.V.M.S., a veterinarian with Kentucky Equine Research (KER).
The cornea usually becomes damaged due to infection from bacteria or fungi, trauma, or other inciting cause. Once damaged or ulcerated, the eye becomes painful and inflamed, necessitating prompt and aggressive treatment. In some cases, corneal ulcers can become uncooperative to treatment, leading to loss of vision and potential enucleation, or surgical removal of the eye.
Human patients with chronic NCP reportedly benefit from fish oil supplementation. According to the study authors, nutritional intervention strategies, such as the increase in the ratio of omega-3 to omega-6 fatty acids, may regulate inflammation and optimize health in NCP patients. Doses of 1,000 mg 2 to 3 times daily are recommended.
In addition to fish oil supplements, other complementary and alternative therapies reportedly benefit patients with NCP, such as exercise and acupuncture.
â€œNote that the quality of the fish oil will influence its effectiveness. EOâ€¢3, a high-quality, palatable, cherry-flavored fish oil, contains 6,750 mg DHA and EPA per 30 mL serving,â€ explained Kathleen Crandell, Ph.D., a nutritionist with KER. A 500-kg (1,100 lb) horse with a corneal ulcer should get 30 ml EOâ€¢3 two to three times daily.
*Dieckmann, G., S. Goyal, and P. Hamrah. 2017. Neuropathic corneal pain: Approaches for management. Ophthalmology. 124(11S):S34-S47.