Question
I own a mature, idle Thoroughbred-cross mare with shivers. She has free-choice access to orchardgrass hay while the grass is starting to grow. The pasture grass is a mixture of fescue and orchardgrass. She is fed 1.5 lb (0.68 kg) of a high-fat performance feed twice a day along with vitamin E and flax supplements. Does she have an increased risk of developing laminitis as the grass intake increases because of her shivers diagnosis?
Answer
Spring grass causes stress for many owners managing horses. Horses with metabolic and endocrine diseases, like metabolic syndrome and pituitary pars intermedia dysfunction, are at a greater risk of pasture-associated laminitis. They require careful management and restriction when it comes to overconsumption of cool-season grasses, which frequently contain large amounts of water-soluble carbohydrates.
Horses with shivers do not require special dietary restrictions unless they have a concurrent condition. If diagnosed with both polysaccharide storage myopathy (PSSM) and shivers, horses will likely require diet changes and possibly grass restriction to reduce intake of nonstructural carbohydrates.
If your mare has no signs of metabolic disease or other underlying risk factors, she should not be at any greater risk of pasture-associated laminitis. Assuming she has no history of laminitis, there appears to be no reason to restrict her grass intake besides maintaining a healthy body condition if she is going to remain out of work. Use a weight tape periodically to help track any changes in body condition. If she gains weight quickly as the grass comes in, you may consider limiting her consumption to avoid obesity as the grazing season progresses.
Regarding the concentrate portion of the diet, the only concern is that 3 lb (1.3 kg) of feed doesn’t meet the manufacturer’s minimum recommendation to supply the necessary levels of nutrients. As an idle horse, she doesn’t require the calories from 5 lb (2.25 kg) of feed daily, so I suggest adding a concentrated micronutrient supplement to fortify the low-intake diet.
The addition of vitamin E is often suggested for horses with a neuromuscular condition like shivers. Using a natural-source vitamin E supplement (listed on labels as d-alpha-tocopherol) versus a synthetic form (dl-alpha-tocopherol) will provide superior absorption into the bloodstream. Nano-E is a natural-source, liquid vitamin E supplement that features superior bioavailability because of its nanodispersion technology.
Finally, consider adding a direct source of the omega-3 fatty acids docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) to your mare’s diet. Flax is a source of the omega-3 alpha-linolenic acid (ALA). While the horse can turn ALA into DHA and EPA, the conversion is inefficient, so it is best to feed a direct source. EO-3 is a marine-derived oil that is a direct source of DHA and EPA.
