Description, occurrence and significance of Mycoplasma seminis sp. nov. isolated from semen of a gyrfalcon (Falco rusticolus).

The Mycoplasma strain ARNO was isolated from the semen of a clinically healthy gyrfalcon (Falco rusticolus). Colonies of strain ARNO grew in fried-egg shape on Mycoplasma agar plates (SP4). The organism did not ferment glucose or hydrolyze arginine or urea; hence, organic acids are assumed as energy source. Growth was sterol-dependent and optimal growth temperature 42 °C, with a temperature range from 20 to 44 °C. Strain ARNO was not identified as a representative of any of the currently described Mycoplasma species by alignment of the 16S rRNA gene sequence and 16 S-23 S intergenic transcribed spacer region, or immunobinding assay. Hence, strain ARNO represents a novel Mycoplasma species for which the name Mycoplasma seminis sp. nov. is proposed (DSM 27653, NCTC 13927). After developing a species-specific PCR, the prevalence of M. seminis sp. nov. was determined in adult and juvenile falcons in a commercial breeding center for falcons. Semen samples (n = 171) were obtained from 113 male adults, due to repeated sampling of 39 birds. Female adults (n = 26) were sampled once, while 105 of the 152 juvenile birds were sampled twice via choanal swabs. Mycoplasma seminis sp. nov. was found in the semen of clinically healthy adult males (3.5 %) as well as in the respiratory tract of female (34.6 %) and juvenile birds (59.2 %). After comparison of semen samples with (2.9 %) and without M. seminis sp. nov. identification, no indications for a potential influence on the semen quality were demonstrated. Hence, M. seminis sp. nov. seems likely to be of commensal character in falcons.

Identification and differentiation of avian Mycoplasma species using MALDI-TOF MS.

The identification of avian Mycoplasma spp. by conventional immunologic, phenotypic, and molecular methods can be demanding and time-consuming. We evaluated MALDI-TOF MS for its suitability to identify avian mycoplasmas at the species level. We generated a mycoplasma spectral database of 36 main spectrum profiles (MSPs) representing 23 avian Mycoplasma spp. using 23 type and reference strains, 1 live vaccine strain, and 8 clinical isolates. We then used 112 avian Mycoplasma clinical isolates of different avian mycoplasmas, 4 Mycoplasma live vaccine strains, and 1 Mycoplasma type strain, previously cultured and identified to the species level by molecular methods, to evaluate the MSP database. Protein extraction and MALDI-TOF MS analysis were performed with a maximum of 3 repetitions per isolate. MALDI-TOF MS resulted in accurate species-level identification with a score of ≥2.0 for 112 of 117 (96%) isolates. The MALDI-TOF MS analysis of 4 of 5 isolates that did not yield a score of ≥2.0 resulted in best-match identifications that were still concordant at species level with the molecular method used for previous identification. Therefore, MALDI-TOF MS is a promising tool for reliable identification of avian Mycoplasma spp.