Question
Irish is my 13-hand (132 cm), 18-year-old Welsh/Belgian crossbred gelding. He weighs about 950 lb (432 kg), so he’s a stocky guy! He is in light work, driving 3-6 miles (5-10 km) every other day or so. Occasionally, we go camping, and he will work harder on those days, driving 15-20 miles (24-32 km) per day. He had gained weight over the winter, and we had a hard time getting him back in shape. During this conditioning period, to reward him for his hard work, I let him have a half hour of pasture each morning. Within two weeks, Irish no longer wanted to trot when asked. He tested positive for PSSM1 and ever since then I have been trying to figure out a suitable ration for him. He is fed 18 lb (8.2 kg) of soaked hay, 1 cup of low-starch pellet, magnesium, salt, MSM, vitamin E, and selenium. I haven’t tried a fat supplement yet because I didn’t want him to gain weight. I am trying to get a grip on a ration that will help control his PSSM and support weight loss. I am worried that he is not getting the vitamins and minerals he needs because I soak his hay.
Answer
Regarding optimal delivery of nutrients to an easy keeper, switching to a ration balancer is the best way to supply essential vitamins and minerals in a low-calorie, low-intake form. Most companies offer a ration balancer, and some even have products that complement the predominant type of forage being fed (e.g., alfalfa or grass hay).
If your hay supply is consistent, then you may want to consider having forage analysis done to quantify total carbohydrate and mineral content. This will help you determine if soaking is necessary and how effective it will be, as the amount of sugar lost depends on the total nonstructural carbohydrate (NSC) in the forage. Soaking hay leeches other nutrients, and extended soaking times have been associated with increased nutrient losses and greater microbial contamination.
The amount of supplemental fat needed for optimal health and performance is dependent on the horse. Some PSSM horses benefit from a reduction in dietary starch and sugar alone, while others require various amounts of supplemental fat to show an improvement in attitude and performance. Because fat is a concentrated source of calories, it is not recommended for overweight horses as it can exacerbate the issue. Vegetable oil and stabilized rice bran products are good sources of fat should you wish to offer fat in the future.
Antioxidants offer many health benefits, especially for horses with myopathies. Antioxidant supplementation with vitamin E and/or coenzyme Q10 can increase the horse’s antioxidant defenses and help reduce oxidative damage and stress. Horses that don’t have access to grazing pasture should receive supplementation with natural-source vitamin E to help maintain adequate vitamin E status. Check the source of your current supplement. You may find once you have transitioned to a well-formulated ration balancer you can reduce the number of supplements offered.
Nano-Q10 is an antioxidant product that features coenzyme Q10. This supplement targets muscle health and improves aerobic energy generation in the muscle, which can be beneficial to athletic horses with PSSM and other related myopathies.
