Which minerals do dogs need?
There are different types of macro-minerals and trace minerals that are needed to create a complete and balanced dog food.
Macro-minerals are required at greater than 100mg/Mcal. Below are the required macro-minerals.
Calcium (Ca) makes it possible for teeth and bones to maintain their shape and is actively involved in balancing calcium in a dog’s bone. It is also very important in cell communication and is involved in blood clotting, muscle function, and nerve transmission.
About 99% of all calcium is stored in the teeth and bones.
Too little or too much calcium can create an imbalance in phosphorus-calcium levels. Deficiencies in calcium can cause bone reabsorption, decreased growth, decreased eating or anorexia, limping, lameness, fracturing of the bone, loose teeth, and convulsions. Low calcium can occur in kidney failure, pancreatitis, and eclampsia.
Supplementation may be required but should be done under the strict supervision of a veterinarian due to the risks of mineral imbalance. Excess amounts of calcium can cause limb lameness and joint swelling. It can also cause certain conditions such as secondary hyperparathyroidism.
Phosphorus (P) is vital in many tissues and functions in a dog’s body. It is the second structural component of bone, teeth, RNA, and DNA. It is important for cell growth, cell energy use, and amino acid and protein formation.
AAFCO recommendations are 0.8% for growth and 0.5% for maintenance (adults).
Most of the phosphorus comes from a dog’s diet and is available more readily in animal-based ingredients than plant-based ingredients (phytic acid). Meat tissue (poultry, lamb, fish, beef) is high in phosphorus, followed by eggs, milk products, oilseeds, protein supplements, and grains.
Deficiencies can cause pica, decreased growth, poor hair coat, and bone fractures. Excessive amounts can cause loss of bone mass, urinary stones, the inability to gain weight, and calcification of tissues and organs.
Magnesium (Mg) is involved with the structural composition of bones, plays a role in the metabolism of carbohydrates and fats, and is a part of neuromuscular activity.
AAFCO recommends 0.04% DM for growth and 0.08% DM for maintenance (adult dogs).
Bone products (such as bone meal or lamb meal), oilseed, flaxseed, soybean meal, unrefined grains, and fibers are good sources of magnesium.
Deficiencies can cause stunted growth, muscle contraction and mobility issues, and decreased eating or anorexia. High levels can cause stone formation and paralysis. Kidneys are very important in the regulation of magnesium. The use of certain drugs (cyclosporin, diuretics, etc.) and certain medical conditions can cause an imbalance.
Potassium (K) is the most abundant inside the cells of a dog’s body. It helps in many functions of the body, such as maintaining acid-base balance and osmotic balance, transmitting nerve impulses, and muscle contractility. It is not stored in the body and needs to be supplemented in the diet.
AAFCO recommends 0.6% DM for dogs in all life stages.
Soybean meal, unrefined grains, fiber sources, and yeast are excellent sources of potassium.
Deficiencies can cause decreased eating or anorexia, lethargy, and trouble walking. Over-supplementation is rare but can cause heart and muscle issues.
Sodium (Na) and Chloride (Cl)
Sodium (Na) and chloride (Cl) are important in maintaining osmotic pressure, acid-base balance, and what enters and leaves the body’s cells. Sodium is also important in calcium absorption and the absorption of several water-soluble vitamins.
Deficiencies can cause decreased eating or anorexia, weakness, fatigue, and hair loss. Over-supplementation does not typically occur unless good, quality water is not readily available, but it can cause constipation, seizures, and in some cases, death.
Trace minerals, also known as microminerals, are required at less than 100mg/Mcal. Below are the required trace minerals.
Iron (Fe) Iron is very important for oxygen transport throughout a dog’s body. Deficiencies can cause anemia, a rough coat, lethargy, and stunted growth.
AFFCO recommends 80mg/kg for dogs in all life stages. Foods rich in iron are most meat ingredients (organ meats—liver, spleen, and lungs) and some fiber sources.
Excessive amounts in the diet can lead to decreased eating or anorexia, weight loss, and liver issues.
Copper is important in the formation and actions of different enzymes in a dog’s body, hemoglobin formation (oxygen movement), cardiac function, bone and myelin formation, connective tissue development, and immune function. The liver is the main location of copper metabolism.
AAFCO recommends a minimum of 7.3mg/kg DM for dogs.
Most meats (organ meats from cattle in particular) are rich in copper. The availability of copper in food can vary, making it hard to supplement.
Deficiencies can cause abnormal growth, changes in hair color, bone issues, and neurological conditions. Certain breeds of dogs are susceptible to liver toxicity from too much copper (Bedlington, West Highland White, and Skye Terriers). Excessive amounts can cause hepatitis and increases in liver enzymes.
Zinc is involved with over 100 enzyme functions, protein synthesis, carbohydrate metabolism, skin and wound healing, and the immune system. Zinc is not a toxic substance, but over-supplementation is not recommended since it can interact with other minerals and decrease absorption.
AAFCO recommends 120mg/kg DM for dogs. Foods high in zinc are most meats and fiber sources.
Deficiencies include decreased eating, stunted growth, hair loss, a weakened immune system, and growth disorders. Certain arctic breeds can have deficiencies that may require supplementation even with adequate dietary food levels.
Manganese is involved in many systems, such as fat and carbohydrate metabolism and bone and cartilage development.
AAFCO recommends 5 mg/kg DM for dogs.
Foods rich in manganese are fiber sources and fish meals.
Deficiencies can cause deformities of the bone and poor growth.
Selenium is involved with the immune system, protects cells from oxidative damage, and is involved in normal thyroid function.
AAFCO requirements are 0.11mg/kg DM for dogs.
Fish, eggs, and liver are food products that are high in selenium.
Deficiencies are rare since vitamin E can act as a replacement for selenium in some functions. Prolonged deficiencies can cause a decrease in eating and edema of the body. Excessive amounts can cause vomiting, muscle spasms, falling and weakness, excessive drooling, decreased eating or anorexia, trouble breathing, foul-smelling breath and odor from the mouth, and nail issues.
Iodine is involved with proper function of a dog’s thyroid. The thyroid helps regulate body temperature and is involved in growth and development, skin and hair repair and care, and neuromuscular function.
AAFCO recommends 1.5mg/kg DM for dogs.
Fish, eggs, and iodized salts are food products that are high in iodine. Iodine supplements typically found in commercial foods include calcium iodate, potassium iodide, and cuprous iodide.
Deficiencies and excessive amounts cause the same medical issues such as a goiter, including enlarged thyroid glands, hair loss, lethargy, weakness, decreased eating or anorexia, and fever.