Isolation and antibiogram of aerobic nasal bacterial flora of apparently healthy West African dwarf goats and sheep in Abeokuta Area, Ogun State

Abstract

Studies conducted on the bacterial flora of the respiratory tract in goats or sheep focused on the clinically ill, with fewer studies on the apparently healthy goats and sheep and the antibiogram of isolated organisms. This study was carried out on apparently healthy 54 goats and 43 sheep. A total of seven different bacterial species were isolated from the upper respiratory tracts of the apparently healthy small ruminants using colonial morphology, gram staining and biochemical characterization.Antibiotic sensitivity of the bacterial isolates was performed against 10 commonly prescribed antimicrobial agents and minimum inhibitory concentration (MIC) of the antibiotics was conducted. The overall occurrence rate of bacteria isolated are Pseudomonas spp (42.0% in caprine and 27.3% in ovine); Bacillus spp (36.9%, caprine; 40%, ovine); Mannheima spp, (9.2%, caprine; 23.6%, ovine); Escherichia coli (7.6%, caprine; 9.1%, ovine); Staphylococcus spp (2.5%, caprine); Pasteurellaspp(0.8%, caprine) and Streptococcus spp (0.8%, caprine). The isolation of Pasteurella multocida and Mannheimia haemolytica from the nasal cavity of apparently healthy goats and sheep in this study reflects their possible role in most common respiratory diseases encountered in these small ruminants. All the 174 (100%) isolates were resistant to Amoxicillin and 161 (92.5%) were resistant to Ceftriaxone. One hundred and sixty-eight (96.6%) isolates were sensitive to Ofloxacin and 140 (80.5%) were sensitive to both Gentamycin and Ciprofloxacin and 135 (77.6%) were sensitive to Perfloxin. Staphaureus was resistant to all the antibiotics used except Amoxicillin hence only Amoxicillin can be used for its treatment, while most isolates were susceptible to the antimicrobials tested, as demonstrated by higher MIC value. The emergence of antibiotic resistance to these pathogens  may increase infectious disease burdens and make the rapeutic treatment more expensive.