The dry conditions have really produced a dust problem. The feedlots seem to be hazy, with animals breathing dust and dirt. One major potential health problem is mycoplasma due to injury to the lungs.
Mycoplasma is hard to detect and often impossible to treat, but can spread rapidly and result in big losses in feedlots and cow-calf operations. Until a few years ago, the South Dakota State University (SDSU) Diagnostic Lab would not test for mycoplasma unless a producer asked specifically for the testing. Now we are able to isolate mycoplasma in more than one-third of respiratory tissues submitted.
Many producers who have fed Holstein cattle remember the chronic hacking cough and lameness as a result of swollen joints. We were able to culture mycoplasma bovis from both nasal swabs and joint fluid from these animals. The only means of control was perpetually feeding chloro tetracycline. In our area black and whites were blamed for future problems.