Ask the Expert: Salmonella or respiratory disease?

Posted on November 8, 2012 in Starting Strong - Calf Care
By Dr. Steve Hayes, DVM, Day 1 Technology
Q: I am starting to have some high fevers and signs of pneumonia in my younger calves that are still on milk. I am not used to seeing this in such young animals. Is this a Salmonella issue or something else?
A: Respiratory disease or pneumonia is the second most common disease (after scours) reported in preweaned calves. The key signs of respiratory disease are:
  • High temperature (fever)
  • Runny eyes or nose (often with mucous/snotty appearance)
  • Ears lowered or off balance
  • Unprovoked coughing
  • Heavy breathing
If you have two or more of the above signs in a preweaned calf, you most likely have a calf with pneumonia.
The Merck Veterinary Manual refers to this as Bovine Respiratory Disease Complex. The term “complex” is used because there is so much going on with respiratory disease in cattle. Factors contributing to respiratory disease are:
  • Housing – Calves require good air. The University of Wisconsin has published data clearly showing that the use of mechanical positive low flow ventilation in calf barns to bring in fresh air and push our poor quality air keeps calves healthy.
  • Colostrum/passive transfer – The half life of IgG levels in the blood is roughly 18 to 21 days. Low levels of passively acquired antibodies may contribute to pneumonia in preweaned calves.
  • Bedding/environment – Make sure calves are warm and dry to allow them to stay healthy. Use lots of good quality dry bedding.
  • Biosecurity – Manage all preweaned calf housing to follow all-in all-out principles. Do not allow pathogens from older animals to infect younger animals. Clean. Clean. Clean. Allow your calf facility (hutch or barn) to dry out (after fully cleaned) between calves for at least one week. Do not introduce calves to your facility unless you know their history and disease status of the dam.
  • BVD-PI – Work with your veterinarian to eliminate any BVD-PI animals in the herd. Simple ear notching can be done to help monitor and protect your calves from this immune suppressing disease.
  • Nutrition/immunity – Make sure you are feeding your calves adequate levels of protein, energy, minerals and vitamins. This is where your nutritionist can help.
  • Minimize stresses – Do not perform multiple processes to your young calves at the same time. Example: dehorning, vaccinating and weaning at the same time.
Evaluate how old your calves are when they break. Do you see a correlation between when your calves break versus when something in the above list is happening? If so, change it.
Work with your veterinarian to get a diagnosis. Take tissue samples. Evaluate what pathogens are present. You mention Salmonella. Remember the “complex” term from the Merck Manual? Many different pathogens could be at work here. Only a trained veterinarian used to working with calves can help you sort through this. Use them to find a diagnosis.
  • If it’s a virus, a variety of good vaccines can be of help. Make sure the timing is proper for when your calves are breaking with disease.
  • If it is bacterial in cause, find out what antibiotics will be useful. Use them properly and under direction of your veterinarian. Look at using properly timed bacterins.
Pneumonias in young calves can be very frustrating. Evaluate your operation with the above list and then use your veterinarian to get a good diagnosis and to help develop a proper prevention and treatment program.

Category: Animal health
Starting Strong - Calf Care