Current AI, IB and other mixed respiratory complex in Pakistan

HI there, We are facing a complex disease situation in most of the areas of Pakistan, which is of respiratory in nature showing redness of trachea with mucus and fibrinous plugin bifurcation, MG growth over lungs, yellow to white diarrhoea with mortality of 10% to 50% and morbidity starts from fan side of control sheds surprisingly leaving the pad area birds with very light infection, morbidity and mortality. After three days this disease transfers towards pad areas and after another 3 days birds are again healthy with 2% mortality. We r using enro+doxy+colistine+bromohexin+amantadine for 3 to 7 days which gives 70% success but 30% still are not controlled. Plz guide me in this regard.