Isolation of mycoplasmas from the respiratory tract of horses in Australia.

The research article focuses on mycoplasmas in horses, specifically those found in the respiratory tract. It details the identification of seven different species of mycoplasmas, through biochemical, serological tests and some other properties such as electron microscope appearance, electrophoretic pattern of the cell proteins and more, and their correlation to respiratory diseases in horses.

Mycoplasma Isolation

• The research involved isolating ten mycoplasmas from a sample of 130 nasopharyngeal swabs from thoroughbred horses displaying acute respiratory disease symptoms. Additionally, three mycoplasmas were isolated out of 198 samples from asymptomatic horses.
• Another two mycoplasmas were isolated from 21 tracheal swabs taken at necropsy, contributing to a total of 15 isolates studied.

Testing and Classification of Mycoplasmas

• The scientists subjected these 15 mycoplasma isolates, along with six others previously isolated from the horse’s respiratory tract, to biochemical and serological tests.
• Certain strains underwent further tests for appearance under an electron microscope, the ability to adsorb or agglutinate the erythrocytes of various animal species, and the electrophoretic pattern of their cell proteins.
• Based on the results of these tests, the researchers divided the mycoplasmas into seven different species.

Identification of Mycoplasma Species

• Three of these species belonged to the genus Acholeplasma and were identified as A. laidlawii, A. oculi, and A. equifoetale.
• Of the other four Mycoplasma species, one was identified as M. pulmonis, a common rodent pathogen. Another displayed cross-reactivity with M. felis in serological tests. The remaining two species were identified as distinct to horses and possibly represented new species.

Association with Disease

• From the seven species, only M. pulmonis and the species represented by the strains N3 and N11 were exclsuvely found in horses with acute respiratory diseases.
• A. oculi was isolated from an asymptomatic horse.
• The remaining four species could be found in both apparently healthy horses and those suffering from respiratory diseases, although the majority of M. equirhinis strains were isolated from sick horses.

The research provides significant insight into the mycoplasma species present in the respiratory tract of horses and their possible correlation with respiratory diseases. It can potentially guide further studies on potential therapeutic targets and animal health management.