Comparative Study of Bacterial Isolates in Ovine Mandibular Osteomyelitis and Oral Microbiota of Healthy Sheep

Microorganisms involved in ovine mandibular osteomyelitis (OMO) have not yet been deeply studied. The aim of the present study is to elucidate the microorganisms involved in OMO, comparing them with the microorganisms found in the healthy oral cavity of sheep. Two hundred and five samples were taken from mandibular osteomyelitis lesions, and they were compared with the microbiological results of samples obtained from twelve periodontally healthy sheep. Sixty-four samples (32.98%) of OMO lesions showed pure growths, while 130 (67.01%) were mixed cultures. Microorganisms of the genus Streptococcus were the most frequently isolated (20.95%), followed by bacteria of the genus Pseudomonas (8.50%), Trueperella pyogenes (7.26%), Staphylococcus (6.63%) and Escherichia coli (6.22%). Ninety-one different isolates were obtained from healthy mouths, and again, microorganisms of the genus Streptococcus were the most frequent (16.48%), followed by bacteria of the genus Staphylococcus (13.18%), Pseudomonas (9.89%) and Moraxella (6.59%). Based on these and previous results, it could be concluded that the normal microbiota of the oral cavity could be involved in the development of OMO lesions when there is an injury of the gingiva that enables the entry of bacteria to the oral mucosa that eventually settle locally in bony tissues, causing mandibular osteomyelitis.