Tylosin is an antibiotic from Macrolide group. To date Tylosin Tartrate is known to be the best remedy against Mycoplasmosis. At higher dosed, it also acts against gram positive and gram-negative bacteria. Colistin a cyclic polypeptide antibiotic has a bactericidal action against selected gram-negative bacteria, The primary bacterial effect of Colistin is a blockade of the cell divition of bacteria followed by a secondary progressive lyses. Gentamicin is an aminoglycoside antibiotic indicated for the treatment of a variety of bacterial infections. It is normally used as the sulphate salt. In veterinary medicine gentamicin is used mainly as a solution for injection for , cattle and horses and as an oral solution for poultry.