Ethambutol is a drug used primarily to treat avian tuberculosis, caused by Mycobacterium avium. It is usually given in combination with other tuberculosis medications.
Saggese, Miguel D., et al. Evaluation of multidrug therapy with azithromycin, rifampin, and ethambutol for the treatment of Mycobacterium avium subsp avium in ring-neck Doves (Streptopelia risoria): an uncontrolled clinical study. Journal of Avian Medicine and Surgery 28.4 (2014)
Buur, Jennifer, and Miguel D. Saggese. Taking a rational approach in the treatment of avian mycobacteriosis. Veterinary Clinics: Exotic Animal Practice 15.1 (2012)