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Why Summer Pneumonia in Calves is a Predictor of Poor Mineral Nutrition

How Summer Pneumonia in Calves is a Predictor of Poor Mineral Nutrition

Often, there’s a lull in the chaos for beef producers in the summer. Calving is done, breeding is underway and weaning is a few months away. Your cows are on pasture, grazing and happy. Then, suddenly, an outbreak of summer pneumonia in calves occurs, and you are scrambling to figure out why.

Summer pneumonia in nursing calves can come on suddenly with little warning, and the first sign is often a very sick or dead calf.

What Causes Summer Pneumonia in Calves?

The University of Nebraska defines summer pneumonia as a respiratory disease in pre-weaned calves on pasture. While the direct cause of summer pneumonia is unknown, researchers and veterinarians have found a few direct correlations between outbreaks and these varying factors:

  • Poor mineral nutrition in cows and calves impacts immunity and colostrum quality

  • Reduced immunity in calves after colostrum antibodies wane and the calves’ natural immune system takes over

  • Hot and dusty conditions in late summer break down the calves’ natural defense mechanisms in the lungs, making them susceptible to viruses

  • Temperature swings

  • New older calves being introduced to the herd and shedding viruses

“I like to call summer pneumonia the canary in the coal mine,” says Dr. Jeff Hill, ruminant nutritionist for Ralco. “Like the canaries used to warn miners of carbon monoxide and other toxic gases before they hurt humans, calves are the most vulnerable of the herd and are a beef producer's early warning that nutrition or mineral are lacking.”

What Are the Symptoms of Summer Pneumonia in Calves?

According to North Dakota State University, the symptoms of summer pneumonia can start between three to four weeks and three to five months.

While the most common symptoms include respiratory issues and breathing issues, it can also be high fevers, droopy ears, sluggishness and calves having a hard time keeping up with the herd moving from pasture to pasture.

How Proper Mineral Nutrition Can Help Prevent Summer Pneumonia

“In the past, if a beef producer had summer pneumonia, the vet would tell them to feed more copper,” said Dr. Hill. “But that’s a band-aid for a greater mineral deficiency, and it can actually do more harm than good.”

Mineral ratios and levels must be appropriately sourced and balanced.

For example, if trace minerals like zinc (Zn) and copper (Cu) are incorrectly sourced, their antimicrobial properties will negatively impact the microbe population in the rumen. The rumen is made up of more than one trillion microbes. The antimicrobial properties of Cu and the microbe population in the rumen involved with breaking down forage and nutrients do not mix.

How Proper Mineral Nutrition Can Help Prevent Summer Pneumonia

Instead, Zn and Cu need to break down later in the digestive tract in the small intestine to bypass the rumen and minimize antimicrobial activity while increasing bioavailability to the animal.

Additionally, Zn and Cu compete for absorption sites, so they must be balanced because overloading one can negatively impact the absorption of the other. This means that if levels of one decrease, the other increases, and vice versa.

So, if a vet recommends more Cu to prevent summer pneumonia, then the level of Zn must also go up in the ration. Furthermore, environmental antagonists, mainly molybdenum (Mo), iron (Fe), and sulfur (S) can bind other dietary trace minerals, in particular, Cu. In these cases, over-feeding trace minerals may be needed, but more often than not changing to a mineral source that cannot be interfered with is preferable.

“Bottom line, the solution to summer pneumonia or any mineral deficiency is not to change your level, like feeding more Cu in this case, but to change your form of mineral to something that’s properly balanced and sourced for your herd to meet the challenge at hand,” said Dr. Hill.

When a mineral is balanced correctly, it can provide the immune support calves and cows require to protect themselves against viruses that cause summer pneumonia. When mineral nutrition is lacking or deficient, immunity is compromised, and calves get sick quickly – just like the canary in the coal mine, summer pneumonia in calves is a sign of an underlying trace mineral problem in the whole herd.

Spring vaccinations and proper mineral nutrition are the best prevention tools for summer pneumonia. If outbreaks of summer pneumonia occur, immediately contact your veterinarian. They often prescribe antibiotics and anti-inflammatories that successfully treat the problem if caught early on. Next, contact a ruminant nutritionist to get a mineral consultation to evaluate the root of the problem.

Schedule a FREE mineral consultation with a ruminant nutritionist today by calling 507-337-6916 or emailing 


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