Mycoplasma infection in cattle

I. Pneumonia-arthritis syndrome

Abstract

Mycoplasma spp. are unique microorganisms associated with several disease entities, including a pneumonia-
arthritis syndrome in cattle. One of the challenges in determining the role of Mycoplasma spp. in bovine disease is that this organism has been isolated from both normal and diseased animals. When dealing with field cases of mycoplasma pneumonia, it is common to find mixed infections. Additionally, observations from research studies and clinical experience have indicated that the presence of mycoplasma increases the severity of respiratory disease. There are no pathognomonic signs for mycoplasma infections. Clinical signs associated with respiratory infections include tachypnea, dyspnea, ocular and nasal discharge, depression, decreased appetite, arched stance and fever. Clinical signs associated with joint infections include
stiffness, lameness, difficulty when rising, swollen joints and tendon sheaths, decreased appetite and weight loss. The organism requires special growth media and conditions to be cultured in the laboratory. If a practitioner wants to confirm a diagnosis with a positive culture, he/she must specifically request a mycoplasma culture when samples are submitted to the laboratory. Besides determining the significance of Mycoplasma spp. in disease, the practitioner is faced with recommending appropriate and effective treatments. Response to therapy, both experimentally and under field conditions, is variable and frequently unrewarding. Since mycoplasma organisms are resistant to several therapies, sound biosecurity and biocontainment programs that minimize stress and exposure to the organism are the best recommendations that practitioners can discuss with producers for prevention and control.