It doesn’t take long for a healthy calf to become a sick one. Early detection and treatment of disease can greatly improve the likelihood of success.

During a hands-on workshop at the Professional Dairy Producers of Wisconsin’s (PDPW) Annual Business Conference held in Madison, Wis., Mississippi State University’s Amelia Woolums, D.V.M., shared some recommendations for evaluating calf health.

For starters, it is helpful to know the signs of a healthy calf. Woolums shared the following characteristics of a normal calf:

Rectal temperature: 100°F to 102.9°F (37.8°C to 39.4°C)

Respiratory rate: 22 to 44 breaths per minute

Heart rate: 80 to 120 heart beats per minute

Body condition score: 2.5 to 3.5 out of 5

Behavior: alert and lively; wants to suckle

Eyes: not sunken, no discharge

Ears: not droopy, no discharge

Nose: no discharge, or just a clear discharge

Breathing: no effect

Belly: not tucked up, not distended

Naval: dry, not swollen or painful

Joints: not swollen, no lameness

Manure: toothpaste consistency

Using these benchmarks, calf caregivers can promptly determine if an animal is feeling well or if it needs further attention.

Dealing with dehydration

Due to their small body size, one ailment that can affect calves quite quickly is dehydration. To determine a calf’s hydration status, Woolums demonstrated one method that includes pinching the skin on the calf’s neck. Pinch the skin, turn it 90 degrees, and then let go. In a well-hydrated calf, the skin should go flat in less than 2 seconds.

Another indicator of calf hydration is to look at the eyes. Woolums said to evaluate the space between the eyeball and the edge of the eye. If a calf’s eyes are sunken 3 millimeters (mm), and the skin tent lasts for 5 seconds, the calf is 6 percent dehydrated.

If eyes are sunken 6 mm, and the skin tent lasts for 7 seconds, it is 10 percent dehydrated. With eyes that are sunken 8 mm and a skin tent that lasts for more than 10 seconds, the calf is 12 percent dehydrated.

Once you identify the level of dehydration, calculate how much fluid the calf needs. For example, Woolums said an 80-pound calf that is 6 percent dehydrated would need about 5 pints or 2.5 liters of fluid. (80-pound calf x 0.06 = 4.8 pounds, which is about 5 pints or 2.5 liters).

If the calf can stand and suck, fluids can be fed orally by bottle or esophageal feeder. She encouraged producers to talk with their veterinarian to determine a farm-specific protocol, but she said a generally good rule of thumb is to give half of the fluids immediately and half within the next 12 hours.

The type of fluids provided is also important. “Water is not enough for calves with diarrhea. They have to have electrolytes,” she said. Woolums indicated that there are dozens of options available, but “they are not all the same.”

She said you want an electrolyte that will counteract acidosis, which is particularly important for calves over 8 days of age as those are the ones that are most often acidotic. Good electrolytes contain bicarbonate, acetate, or something similar. Glucose is also important for helping sodium be absorbed. Sodium has to be absorbed for water to be absorbed, Woolums said.

If the calf can’t stand or won’t suck, it needs intravenous (IV) fluids. Woolums recommended contacting a veterinarian in these situations to administer the needed fluids.

Whether it is dehydration or another calfhood illness, attention to detail is a must to return calves to health quickly. “You miss more by not looking than by not knowing,” Woolums said. “It pays to look at the calves and their environment carefully every day.”