PURPOSE: An antibiotic composition containing plant or extract thereof against pathogenic microorganism is provided to ensure strong antibacterial activity against Burkholderia sp. and to apply to a feed. CONSTITUTION: An antibiotic composition against Burkholderia sp. or Haemopillus somnus contains Citrus aurantifolia swingle leaf； Lime leaf or extract thereof as an active ingredient. The extract is isolated by an organic solvent. The organic solvent is methanol, ethanol, propanol, butanol, methyl, acetate, ethyl acetate, methyl ethyl ether, diethyl ether, benzene, toluene, hexane, or acetone. The composition is used for treating or preventing respiratory diseases.본 발명은 식물 또는 그 추출물을 유효성분으로 포함하는 병원성 미생물에 대한 항생용 조성물, 그 제조방법 및 상기 조성물의 사료에 응용에 관한 것이다.
