Comparison of the pathogenicity of three Mycoplasma capricolum strains for adult and newborn goats

Abstract

Two experimental infections of goats with Mycoplasma capricolum have been carried out. Adult animals, infected intrabronchially with an ovine strain, O₁₂ (10⁹ CFU/ml), showed mild and transitory respiratory disorders. They shed the organism during the five weeks of observation and developed a seroconversion, detected since the first week by ELISA. Females feeding their kids during the first month were distributed in three groups and inoculated intramammally, with the dose of 2.10⁷ CFU/ml, the first group with O₁₂ strain, the second with a Moroccan caprine strain, and the last one with an Australian caprine strain. A severe mastitis was observed in all animals, accompanied with general disturbance, except in group 1. The infection was transmitted to the newborns by suckling. All kids but one died within 6 to 12 days. These results suggest that:

- adult goats are relatively resistant to Mycoplasma capricolum given by respiratory route ;

- the studied strains may vary in their virulence ; the O₁₂ strain was found the least virulent for adults as well as for suckling kids.