First Report of ' Candidatus Mycoplasma haematomacacae' in Laboratory-Kept Rhesus Monkeys (Macaca mulatta) Maintained in Rio de Janeiro, Brazil

Abstract

Health monitoring programs in animals used as experimental models are essential, since only disease-free subjects are considered suitable for research purposes. In laboratory-kept animals, hemoplasmas have been described as an important confounding variable. Different hemoplasma species have been detected infecting non-human primates (NHP) from Brazil. However, the occurrence of hemoplasma species in laboratory-kept NHP in Brazil has not-yet been assessed. Accordingly, this study aimed (i) to screen laboratory-kept rhesus monkeys for hemoplasmas, (ii) to verify if any of the hemoplasma-positive animals demonstrate hematological abnormalities, and (iii) to assess the genotype diversity of hemoplasma species in NHP from Brazil. Five out of eight (62.5%; 95% CI: 3.05-8.63) rhesus monkeys tested positive for hemotropic Mycoplasma spp. by PCR. Sequencing, phylogenetic, distance, and genotype diversity analyses of partial 16S rRNA gene demonstrate that rhesus monkeys were infected by 'Candidatus Mycoplasma haematomacacae' (formerly 'Candidatus Mycoplasma haemomacaque'). Assessments of partial 16S rRNA diversity of hemoplasma species in NHP suggest that at least four genetically diverse groups may occur in Brazil. Although no hematological abnormalities were demonstrated in rhesus monkeys evaluated herein, future studies are needed to elucidate the influence of 'Ca. M. haematomacacae' as a confounding variable on research studies.

Keywords: animal experimentation; genetic diversity; hemotropic Mycoplasma spp.; hemotropic mycoplasmas; laboratory animals.

Figure 1

Phylogenetic tree based on Bayesian inference made with a total alignment of 750 pb and TPM3uf+I+G model. This tree demonstrates the occurrence of five different clade groups of hemoplasma genotypes occurring in free range or captive non-human primates in Brazil. Only post-probabilities values >50 are shown. Five distinct clades of hemoplasmas from NHP were formed (identified as A to E). Sequences from the present study are located in clade A and highlighted in red. The genotype groups where sequences KCS12401, AB82088, OK157439, OK157441 (Hap_1) and KT314160-KT314164, KU061098 (Hap_2) were allocated according to the genotype diversity analysis are demonstrated next to these sequences’ clades.

Figure 2

Genotype analysis made by DnaSP6 software. Inference and graphic representation were made by TCS Network method on PopART software based on a 750 bp alignment. Sequences from the present study (OK157439 and OK157441) were allocated in Hap_1.

Figure 3

Distance analysis made by Splitstree v. 4.14.6 software applying NeighborNet method based on a 750 bp alignment. Sequences are identified based in clades formed by the phylogenetic analysis. Sequences from the present study are allocated at group A (red) together with sequences from ‘Ca. M. haematomacacae’ from USA and Japan. Hemotropic Mycoplasma sp. sequences obtained from Sapajus sp. monkeys from northeastern Brazil are allocated in group B (blue). Sequences of ‘Ca. M. kahanei’ and sequences obtained from S. sciureus monkeys from Brazilian Amazon are allocated in group C (green). Sequences obtained from Alouatta sp. from southern and southeastern Brazil are identified in yellow (those from clade C) and purple (those from clade E). The genotype groups where sequences KCS12401, AB82088, OK157439, OK157441 (Hap_1) and KT314160-KT314164, KU061098 (Hap_2) were allocated according to the genotype diversity analysis are demonstrated next to these sequences’ clade identification.