This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bacteriology, Subject name: Microbiology
A veterinary doctor had fever for 15 days. His blood culture in special laboratory media was positive for Gram-negative sho bacilli which were oxidase positive. Which one of the following is the likely organism grown in culture? 
Select and explain. 
A. Pasteurella spp., B. Francisella spp., C. Baonella spp., D. Brucella spp.
D: Brucella spp.
Answer: D: Brucella spp. 
Explanation: Pasteurella sp-Gram --ve bacilli oxidase +ve causes cellulitis but no fever Francisella sp-Gram --ve sho bacillus, oxidase +ve, causes Tularemia ahrosis but no PUO(Pyrexia of unknown origin) Baonella -- Gram --ve red, oxidase +ve Brucella, Gram --ve, sho bacillus causes PUO Ref : Ananthanarayana textbook of Microbiology 9th edition Pgno : 339