Animal Science Department


Date of this Version



Presented at Range Beef Cow Symposium XXI, December 1-3, 2009, Casper, Wyoming. Sponsored by Cooperative Extension Services and the Animal Science Departments of the University of Wyoming, Colorado State University, South Dakota State University, and the University of Nebraska¬Lincoln.


Year in and year out, diseases of the respiratory system are a major cause of illness and death in cattle from 6 weeks to two years of age. Sadly, this is as true today as it was 30 years ago despite development of new and improved vaccines, new broad spectrum antibiotics, and increased fundamental knowledge as to the cause of disease. WHY? I don‟t have the answer and I doubt if anyone does. As a pathologist, I often see firsthand the devastating effects that bacteria can have in the lungs of cattle that die from respiratory disease complex or shipping fever. I often wonder to myself, “They know this calf had a bacterial pneumonia, why did they send it in?” “What do I need to know to do a better job?” Is there some missing bit of information that will tie this all together?” As a pathologist, I also see lungs from cattle suspected of shipping fever that might have looked abnormal in the field but with no evidence of pneumonia when examined microscopically. Obviously there is a disconnect somewhere. This presentation will focus on shipping fever and will mention some conditions that can be mistaken for bovine respiratory disease. I am a diagnostic pathologist so will not dwell on vaccinations or treatment; that is the purview of other animal health professionals, especially your veterinarian. Diagnostic considerations will be a constant theme. There are a number of reasons for performing diagnostics on diseased animals; the most important is learning.