Respiratory mycoplasmosis of small ruminants in Ethiopia

An attempt was made to determine the distribution of Mycoplasma causing mass respiratory disease outbreaks in small ruminants in Ethiopia. Isolation of Mycoplasma from clinical samples and immure-enzymatic assays like the dot immunobinding on nitro-cellulose paper (dot blot), membrane filtration dot (MF dot) were applied as screening techniques. The prevalence of different Mycoplasma strains namely, M. capricolum subsp. capripneumoniae (Mccp) or type M. F.38, M. mycoides subsp. mycoides large colony goat biotype (MmmLC), M. capricolum subsp. capricolum (Mcc) and M. agalactiae was recorded. The association of saprophytic types like M. ovipneumoniae and M. arginini was also observed. The majority of these strains were directly detected by dot blot test on pneumonic lung extracts and pleural exudate samples collected from respiratory cases that occurred in different regions in Ethiopia. The dot blot results were later correlated with bacteriological and MF dot findings. All samples including dot blot assay positive were subjected to Mycoplasma isolation. Isolated strains were biochemically characterised and finally identified by membrane filtration dot (MF dot) technique that applied Mccp specific monoclonal antibodies (MAB) and hyperimmune anti-sera (HIS) for other Mycoplasma. These findings illustrate the distribution pattern of Mccp and other Mycoplasma in disease outbreak regions. The natural resistance of sheep to clinical Mccp in the Ethiopian condition is assessed. Although, nasal swabs from sheep gave Mycoplasma growth, none of the sheep from mixed flocks at Arbaminch had CCPP like clinical disease. (Résumé d'auteur