Here's the link if you want to read the entire article, also good vaccination, good nutrition and a good mineral program helps prevent.
http://www.ext.vt.edu/pubs/beef/400-304/400-304.html
Treatment
Mycoplasma is very difficult to treat because many commonly used antibiotics do not work well. Penicillin, Polyflex®, Naxcel®, Excenel®, and Excede® kill bacteria by destroying the cell wall. Since Mycolplasma does not have a normal cell wall, these antibiotics are ineffective in treating it. Micotil® shows little or no activity against Mycoplasma as well.
Oxytetracycline (the active ingredient in LA-200®, Biomycin 200®, Tetradure 200®, and other generics) has produced mixed results in treating Mycoplasma. In one study 50 percent of M. bovis isolates were resistant to oxytetracycline. Tulathromycin (Draxxin®) is the only drug approved for Mycoplasma, and in one study, was the drug most likely to be effective (Godinho, et al., 2005). Draxxin® provides the most convenient treatment of Mycoplasmosis because one dose provides seven to 14 days of therapeutic blood concentrations against Mycoplasma and Mannheimia haemolytica, Pasturella multocida, and Histophilus somni, all causes of BRDC. Other drugs that show good results are Nuflor® and Adspec®. Baytril® and A180® can also be effective in treating Mycoplasma when there is a mixed infection with M. haemolytica and Mycoplasma.
The two most important factors in the treatment of Mycoplasma are early recognition and prolonged treatment. Calves treated early in the course of the disease respond fairly well. The need for longer treatment than usual for BRDC is underscored by the fact that without extended therapy, 30 percent to 70 percentof the calves can relapse and require treatment again. Each time a calf relapses it will have more lung damage and be less likely to recover. Current recommendations are to provide continuous therapeutic levels of antibiotics to calves with Mycoplasma pneumonia for 10 to 14 days.
Chlortetracycline at a rate of 0.25 to 1.0 grams per 100 pounds of body weight per day can be added to the feed to extend the therapy protocol to the recommended 10 to 14 days. If a Mycoplasma infection is suspected, a veterinarian should be consulted in developing a treatment protocol that will fit these guidelines and best meet the needs of the operation. Using antibiotics to treat swollen joints is usually unrewarding once the pneumonia has been controlled. The most effective treatment for arthritic calves is to provide easy access to feed and water to prevent starvation and dehydration. It may also be necessary to run these animals to feed and water several times daily until they have begun to recover. The most fortunate aspect of this disease is that it appears, given enough time, a large number of calves will recover. It can take weeks to months for the joints to fully recover and the cattle to start gaining weight.
