Oral electrolyte products can be life-savers for scouring calves. They are important rescue tools because they reverse dehydration caused by lost fluids; correct acid-base and electrolyte balance in the digestive tract and bloodstream; and provide nutritional support.

However, North Carolina State University researcher and veterinarian Geof Smith says correct use of electrolytes is critical. And his research has proven that not all electrolyte solutions are created equal. Following are four recommendations from Smith for successful electrolyte use:

1. Do not feed electrolytes to calves whose digestive tracts are fully compromised. If calves are ill to the point that they are not suckling or swallowing, they probably have lost intestinal motility as well. In that case, the electrolyte solution will just pool in the stomach and cause bloat and rumen acidosis, supplying no benefit to the calf. So, “drenching” sick calves that are not suckling with electrolyte solution via an esophageal feeder is counterproductive. Calves that are too sick to drink need intravenous fluid therapy instead.

2. Continue feeding milk or milk replacer along with oral electrolyte solutions. No oral electrolyte products, even those labeled “high energy,” supply enough nutrients to support the nutritional needs of calves, especially because those animals are losing nutrients via scours. Somewhere along the way, it became a popular concept that scouring calves need a “break” from milk feedings, and/or that feeding milk to scouring calves would supply nutrients for gut bacteria to use as an energy source. There is no scientific basis for these theories. Withholding nutrients from milk will only exacerbate negative energy balance and make sick calves weaker.

3. Be careful of mixing electrolyte powder with whole milk or milk replacer. While continuing to feed milk-based nutrients is important, the two products should be fed separately most of the time. There are a few products that are approved to be fed directly with milk replacer, however most oral electrolytes (particularly those containing high concentrations of bicarbonate) should be fed separately. Suspension of electrolyte powder in the correct volume and temperature of water is critical to promote calves’ absorption of the products. Carefully read and follow labeled mixing instructions, as they may vary between products.

4. Choose electrolyte products carefully based on contents. Following are some guidelines for selecting electrolyte products:

  • Ideal sodium content is between 90 and 130 millimoles per liter of solution (mM/l)
  • Amino acids are necessary for sodium absorption. Look for glycine on the label.
  • Osmolality values (concentration of particles in the solution) should be between 350 and 600 mOsm/L. Products above 600 mOsm/L are too concentrated and can cause further digestive tract damage and/or bloat.
  • An alkalinizing agent, such as bicarbonate, acetate or propionate, is critical for correcting metabolic acidosis. Research has shown that bicarbonate tends to raise the pH in the abomasum, creating an environment that could encourage further bacterial growth. Acetate is the preferred alkalinizing agent.
  • Fiber additives, such as psyllium or dialine, reduce calves’ energy levels and are not recommended.