The present invention relates to a method for substantially preventing a reduction in feed intake in an animal which occurs when said animal is administered an antibiotic, the method comprising administering to an animal in need of prevention of a reduction in feed intake, increasing doses of a composition comprising one or more antibiotics. The present invention also relates to a method for treating laminitis and fermentative acidosis in an animal in need of said treatment, the method comprising administering increasing doses of a composition comprising one or more antibiotics. The present invention further relates to a method for treating equine grass sickness and pulpy kidney in an animal in need of said treatment, the method comprising administering increasing doses of a composition comprising one or more antibiotics.