Feeding Facts for Weanlings

Courtesy of Uckele Health & Nutrition

Although weanlings have intensive nutritional needs, they are often fed like a smaller version of an adult. Don’t shortchange your weanling; make sure your feeding plan is meeting their calorie, mineral and vitamin needs.

At 4 months, the weanling has higher daily total mineral needs than they do as a yearling, despite having lower daily calorie needs. During rapid growth, nutrient dense diets are required that have high levels of protein/amino acids and minerals per calorie. Trying to feed weanlings the same diet as an adult is severely inadequate.

Calories:  Calories are actually the easiest part of feeding weanlings.  In fact, most are too heavy and this has been linked to developmental orthopedic disease.  A 6 month-old weanling requires 7% fewer calories than he will at maintenance at full adult weight.  Also, by feeding him 93% of the adult diet, he will get 7% less protein and minerals.

Minerals: The foal’s diet can’t create the minerals it needs for growth, and stockpiles at birth are minimal to none. This is where the needs of the weanling and those of the adult show the greatest difference.  For example, the 6 month-old weanling needs almost twice as much Calcium and Phosphorus as he will when an adult.  Obviously 93% of the adult diet won’t get the job done.  The weanling may be falling short by as much as 20 grams of Calcium.

Protein: While calorie requirements are lower, protein needs are 7% higher and Lysine is 10% higher.  If you are feeding the adult diet at the 7% reduction, the gap gets wider.  For a horse that will mature to 50o kg this amounts to a deficit of 90 grams of protein overall and 4 grams of Lysine *if* the adult diet was adequate for Lysine in the first place; many are not.

The Solution:  What to do about this? Fortify the adult diet with modest levels of grain/concentrates for the weanling.  Tweaking the adult diet to fill weanling needs is not terribly difficult or expensive but the pay back in terms of growth, health and soundness can be enormous.

  • Assuming the adult diet meets minimum protein and mineral requirements, look for a supplement with about 25% protein, Lysine minimum 1.5% and 5% Calcium with a balanced mineral profile.  Feed 1 pound per day of this.
  • If you are already feeding supplemental minerals and don’t need to add more, it’s very useful to have an unsupplemented high protein source.  Look for 40+% protein, at least 2% Lysine and a mixture of milk/whey protein with vegetable sources.  Feed 1/2 lb per day.  If total protein is adequate but is all or most from hay with unknown Lysine content, supplement with an amino acid supplement containing 10 grams Lysine and 2 grams Threonine per dose.
  • Finally, with no pasture available you need for fall and over the winter, think about essential fatty acids. Omega-3 fatty acids are fragile and largely destroyed when hay cures and during storage.  Adequate supply is required by the eyes, heart and may even influence disposition.  Flax and Chia are good sources, 4 to 6 ounces/day.