Dehydration in Dairy Calves

It requires careful observation, attention to individual calves, and the ability to monitor dehydration. Sick calves may lose up to 10% of their body weight in a single day when they are scouring and dehydration, not microorganisms, typically kills these scouring calves. Therefore early identification and treatment of dehydrated calves will help increase calf survival rates.

To evaluate dehydration, first you need to evaluate the fecal scores of your calves. Those with very loose or runny feces are at a high risk of being dehydrated. Inspect those calves that are at risk for the classic signs of dehydration: sunken eyes, dry mouth and nose, weight loss, fast or very slow pulse, cold ears, and/or cold legs.

A clear test for dehydration is the skin tenting check. To tent the skin, firmly pinch the loose folds of skin on the neck of the calf and check to see how long the skin remains tented. If it remains tented for 2 to 6 seconds, the calf is moderately dehydrated and longer than 6 seconds indicates that the calf is severely dehydrated.

One of the easiest ways to treat dehydration is by feeding calves an electrolyte solution that can be purchased from a feed store or online. There are many different brands of electrolytes but the one to use should contain all of the following ingredients: glucose for energy; an alkalinizing agent to treat acidosis, such as bicarbonate, acetate, citrate or lactate; sodium, potassium, and chloride to replenish lost electrolytes. Some brands may include other ingredients such as glutamine, glycine and gelling agents. As long as the primary ingredients are included, the rest are personal choice.

Feed moderately dehydrated calves 2 quarts of a commercial electrolyte solution, mixed according to the label recommendations twice daily. You may also want to feed an additional feeding at midday. Continue to feed dehydrated calves milk or milk replacer but do not mix electrolytes with the milk feeding in order to provide them with the extra fluids and energy that they need. If you are feeding waste milk, you should wait at least 30 minutes after milk feeding before feeding electrolytes, since some electrolytes contain bicarbonate or citrate which can prevent milk clotting in the abomasum. Electrolytes should be fed before or after milk replacer or milk for 2 to 4 days or until the calf is no longer scouring and does not appear to be dehydrated based on skin tenting and observation. Calves need a great deal of fluid to make up for what is lost during scouring and careful observation and treatment can prevent the high mortality rate due to dehydration from scouring.

J. Heinrichs, Professor of Dairy & Animal Science and  Sylvia I. Kehoe, Ph.D. Candidate