Causes of calf diarrhea – Dr. Jeremy Schefers, University of Minnesota

Click here to download Schefers’ PowerPoint presentation.

By Progressive Dairyman Editor Peggy Coffeen
When a young calf breaks with scours, 80 percent of the time the cause is from one of three sources.

At the Vita Plus Calf Summit, Dr. Jeremy Schefers, University of Minnesota, explained how to protect calves from falling victim to one of these scour culprits – rotavirus, coronavirus or cryptosporidiosis – or all three.

It is important to first understand that antibiotics are not effective against this triple-threat because none of them are a bacteria. Rotavirus and coronavirus are viral, and cryptosporidiosis is a parasite.

“Nothing in my vet box is going to treat these problems,” Schefers said.

While providing electrolytes to combat dehydration may help calves recover, nothing is effective against the actual bug.

“We don’t have a good way to treat it, so we have to think about prevention,” he added.

Preventing rotavirus and coronavirus
Coronavirus in the calf’s environment is easily killed by heat, sunlight and disinfectants. Rotavirus, on the other hand, does not go away so easily. While this virus is resistant to many detergents and disinfectants, the most effective defense are the antibodies found in colostrum and transition milk. In trials, calves challenged with rotavirus that received colostrum, followed by milk from the second and third milkings after calving, displayed fewer days with scours.

“We can stop these viruses with antibodies,” Schefers said.

An easy way to boost calves’ intake of antibodies after the initial colostrum delivery is to add it into the subsequent feedings. This can be done by freezing excess quality colostrum in ice cube trays or buckets, depending on what is most practical for a particular farm, and then thawing and mixing it with the milk or milk replacer.

Vaccinating dry cows for these viruses is another effective way to boost the calf’s immunity.

Control cryptosporidiosis with cleanliness
Unlike the viruses, cryptosporidiosis is a parasite and cannot be treated by antibodies. Its method of transmission is by consumption of feces, such as when a newborn calf sucks on the cattle panel surrounding its hutch. If the pen has residual manure from the prior calf, the newborn can easily ingest it and become infected.

Schefers said, in many cases, cryptosporidiosis is a cleanliness problem. The good news is it can be easily fixed with proper sanitation. When cleaning calf facilities, first remove all of the bedding, then powerwash the pens and paneling. Be sure to follow the powerwashing step by rinsing the entire surface with a low-pressure hose.

“Splattering it all over the surface [with a pressure washer] keeps it in the calf environment,” Schefers explained, reinforcing the final rinse of the calf facilities.