Detection and Identification of Mycoplasmopsis agassizii in Captive Tortoises with Different Clinical Signs in Italy

Abstract

Mycoplasmopsis agassizii causes the Upper Respiratory Tract Disease (URTD) in tortoises. The severity of the disease usually ranges from mild to severe respiratory signs. Animals can recover, die, or become asymptomatic carriers and are source of infection for other tortoises. This study describes (i) the clinical history and the results obtained in ten years of diagnostic PCR activity for detecting M. agassizii in different species of captive tortoises in Italy, and (ii) the phylogenetic analysis of the 16S rRNA gene sequences of M. agassizii. A total of 26.0% out of 169 samples resulted positive by PCR and 32 out of 75 (42.7%) animals with symptoms were positive. Sequences ob-tained from the PCR products were conserved, differed from the sequence of the M. agassizii type strain PS6, and were identical to many M. agassizii sequences deposited in databases. In particular, the sequences were identical or very similar to sequences obtained previously from tortoises in It-aly. Since samples collected from different anatomical sites resulted positive, it is suggested that pools of conjunctival, nasal and oral swabs are tested for diagnostic purpose in both symptomatic and asymptomatic animals.