IMPROVING BONE DENSITY - the role of nutrition

1. IMPROVING BONE DENSITY- the role of nutrition Nia O’Malley Connolly’s Red Mills Tendrleen Horse Feeds

2. Accelerated Growth • Youngstock production dictated by industry trends • Industry has strong desire to accelerate growth for the sales ring • Australian study found intensively fed horses were consistently heavier, taller and better developed in the cannon bones than horses on lower nutrition levels

3. Skeletal Growth * BMC: 68% complete at 6 months, 76% complete at 12 months

4. Bone Mineralisation • Bone mineralisation begins during the last three months of pregnancy • Foetal liver stores minerals needed for mineralisation after birth • The newborn foal born with 17% of its adult BMC

5. Balance is Key! • Very high calcium supplementation leads to a depression of zinc absorption • Very high phosphorus levels will negatively influence calcium absorption • High zinc levels interferes with the uptake of copper • Low magnesium levels affect calcium absorption

6. Oats Alone? • High grain diets immediately unbalance bone metabolism, as grains are low in calcium and magnesium and reasonably high in phosphorus • While a calcium deficiency may not reduce size, the skeleton is weak, porous and fragile, and prone to breakdown

7. Feeding the Broodmare • If the mare’s calcium intake is not adequate during gestation and lactation, it will result in skeletal mineral loss in the foal • Foals born of calcium deficiency have smaller cannon bone diameters at birth • Mare’s milk drops significantly at about the seventh week of lactation, which could negatively influence foal growth rates

8. Vitamins & Mineralisation • Vitamin D acts by increasing the intestinal absorption of calcium and phosphorus • Deficiency of vitamin D will exacerbate an existing imbalance in calcium : phosphorus • Vitamin A deficiency leads directly to loss of bone strength and thinning of the bone cortex

9. Bone Strength & Protein • However bone strength does not only depend on bone mineralisation • But also on the quality and quantity of protein • Protein provides the framework base upon which minerals are deposited

10. Proteins are comprised of chains of amino acids 12 amino acids can be synthesised within the horse’s body However 10 need to be supplied by the diet Essential Amino Acids Arginine Histidine Isoleucine Leucine Lysine Methionine Phenylalanine Threonine Tryptophan Valine What are amino acids?

11. Protein • Provision of high-quality protein is important to support optimal growth and weight gain in young horses • A deficiency of certain amino acids will do more to depress growth rate than any other nutrient

12. Study in Finland: • Two groups of weanlings fed different protein supplements • The weanlings fed higher-quality protein had more growth of the circumference of their cannon bone • Due to greater intake of essential amino acids

13. Broodmares & Protein • Maintenance requirements for the first 8 months • However the protein requirement increases greatly during the 9th, 10th and 11th month • The first three months of lactation are equally as important

14. Exercise: Also a factor! • Bone is constantly remodelling itself in response to the forces of impact and loading • Remodelling increases bone density by removing existing bone and adding new bone to areas where forces are greatest

15. Effect of Exercise on Bone • Weanlings paddock raised & exercised daily vs. box raised • Paddock raised weanlings had 33% higher bone densities • Arab weanlings kept: in stalls 24/day, on pasture 12/day, on pasture 24/day • Pasture weanlings had increased bone mineralisation

16. To Conclude! • Maximising bone density by building stronger bone is achieved through a combination of both nutrition and exercise • Nutrients such as protein, calcium, phosphorus, other minerals and vitamins must be provided in the correct amounts relative to each other, and in balance with the amount of energy being fed

17. Thank you for your attention! Any questions? M: 087 9902651 E: nomalley@redmills.ie