In this investigation, 1383 sheep were clinically examined in the slaughterhouse during the winter season. Fifteen and eighteen percent of the sheep showed clinical findings of respiratory diseases particularly of coughings and nasal discharges. But, the postsloughter examinations revealed the existance of macroscopic respiratory lesions in 33.6 percent of the sloughterd sheep essentially of chronic parasitic pneumoina. Consequently, it should be noticed that atleastfifty percent of the sheep involved in chronic parasitic pneumonia could be falsely symptom less.
)