Complete Guide to Feeding and Nutrition for Adult Horses: Bone Health and Supplementary Feeding

Recommended Diet Types

For adult horses, the foundation of a healthy diet is high-quality forage (hay or pasture). Supplementary feeding may include:

• Hay: Timothy, orchard grass, or bermudagrass hay provide fiber and nutrients. Legume hays like alfalfa are higher in protein and calcium, suitable for horses needing bone support.
• Concentrates: Oats, barley, or commercial feeds supply energy and protein. Choose low-starch or senior feeds for horses with metabolic issues.
• Balanced Supplements: Commercial vitamin/mineral premixes ensure complete nutrition.

Grains alone are insufficient; horses need at least 1-1.5% of their body weight in forage daily.

Portion Sizes and Daily Calorie Needs

Calorie requirements vary by weight, activity, and metabolism. A typical adult horse (1100 lbs / 500 kg) in light work needs about 15-20 Mcal of digestible energy per day. Use the table below as a guide:

Feed concentrates at 0.5-1% of body weight daily, split into multiple meals. Adjust based on body condition score (BCS 5-6 ideal).

Feeding Frequency and Schedule

Horses are grazers; feed at least 2-3 times daily. Provide hay free-choice or at least three meals. Concentrates should be divided into two or three equal portions. Avoid feeding more than 5 lbs of grain per meal to reduce colic risk. Consistency is key.

Essential Nutrients

• Protein: 10-12% crude protein for adult horses; 14% for lactating mares. Good sources: alfalfa, soybean meal.
• Fat: 3-6% of diet; higher fat (10-12%) for performance horses. Vegetable oils are energy-dense.
• Carbohydrates: Primarily fiber from hay; limit starches. Fructans in grass can cause laminitis.
• Vitamins: Vitamin A, D, E (important for muscle and immune function). Minerals: Calcium, phosphorus (ratio 1.5:1 to 2:1), magnesium, zinc, copper, selenium.

Toxic or Harmful Foods

Avoid the following:

• Moldy hay or grain (can cause respiratory or digestive issues)
• Lawn clippings (ferment quickly, risk of colic)
• Avocado, chocolate, caffeine (toxic to horses)
• Excessive grain (leads to laminitis, colic)
• Rhubarb, potato leaves, tomato leaves (contain oxalates or solanine)

Water Intake

Adult horses need 5-10 gallons (20-40 liters) of fresh, clean water per day; more in hot weather or heavy work. Check water frequently, especially in winter when freezing is a risk.

Beneficial Supplements

For bone health, consider:

• Calcium and Phosphorus (balanced ratio)
• Vitamin D (aids calcium absorption)
• Omega-3 fatty acids (anti-inflammatory)
• Glucosamine and chondroitin (joint support)
• Probiotics and prebiotics (digestive health)

Consult a veterinarian before adding supplements.

Differences in Feeding by Life Stage

Foals (birth to 1 year)

Foals nurse and begin eating small amounts of creep feed (18-20% protein) at 2 months. Ensure proper Ca:P ratio (2:1). Weaning at 4-6 months.

Adults (1-15 years)

Maintain body condition with high-quality forage and balanced concentrates as needed. Avoid overfeeding.

Seniors (15+ years)

May require senior feeds (easier to chew, higher protein/fat). Soaked hay cubes or pellets if dental issues. Monitor for weight loss or metabolic disorders.

Signs of Healthy vs. Poor Diet

Healthy: Shiny coat, bright eyes, good body condition (BCS 5-6), regular manure, normal appetite, and energy levels.

Poor: Dull coat, lethargy, weight loss or obesity, diarrhea or constipation, excessive gas, hoof issues, or colic. Annual dental exams and fecal egg counts help monitor health.