What is in this article?:
Pneumonia can affect the health of calves of any age, but particularly frustrating is summer pneumonia in nursing calves. Researchers have mobilized to learn why this cattle disease happens.
Is a virus involved?
Researchers want to find out more about the pathogens involved in summer pneumonia. Woolums says coronavirus is one bug of interest because the virus has been found on nasal swabs of some sick calves.
“But we can also find coronavirus in normal calves. We don’t know if a virus is the actual cause. Just because you find it on the nasal swab doesn’t necessarily mean it’s involved with illness,” she says.
“The fact some herds have more trouble with pneumonia than others might mean they have some pathogens present that are not present in other herds, but we don’t know,” says Smith. “It may be something like bovine respiratory syncytial virus or bovine virus diarrhea that is making them more vulnerable to other respiratory pathogens.”
Survey seeks disease associations
Woolums says earlier work on summer pneumonia seemed to indicate that certain management practices are associated with summer pneumonia.
“We mailed a list of questions to producers in Georgia, Florida, West Virginia, Kansas, Iowa and Nebraska, asking about their management and whether they had calf pneumonia. We did find some significant associations,” she says.
“We asked whether the producers saw any calves with respiratory disease, and also the proportion of calves they treated for pneumonia. Some things were associated with whether they saw respiratory disease, and different things were associated with the proportion of calves they treated. For example, if a farm had calf diarrhea, they were more likely to also see calves with respiratory disease. And farms that used artificial insemination were more likely to treat a larger proportion of their calves,” she says.
Depending on the conditions — whether it was low-stress handling, if the weather was hot or inclement, or corrals were dusty — there might have been factors making them more vulnerable. “It’s also possible that when calves are sorted away from their mothers and grouped together, they have more opportunity to spread respiratory viruses or bacteria among themselves,” she says.
Heather Smith Thomas is a rancher and freelance writer based in Salmon, ID.
You might also like: