This study was carried out on 40 diseased buffaloe calves suffered from severe respiratory disturbances and 10 apparently clinically healthy calves that served as control group. Mycoplasma species were identified from all diseased samples of lung and pleural fluids, 75% of nasal swabs and 40% of plumonary lymph nodes. E.coli and Candidia albicans were isolated from some nasal swabs, lung and pleural fluid of diseased samples. Antibiogram for the isolates of Mycoplasma revealed that the best sensitive antibiotics were tetracycline, erythromycin, chloramphenicol, kanamycin and naldixic acid. Serum biochemical analysis showed highly significant (p < 0.01) decrease in iron and calcium levels in diseased sera with a highly significant (P<0.01) increase in serum copper concentration without any significant (P<0.05) alterations in serum inorganic phosphorus level. T