A metagenomic survey of the fecal microbiome of the African savanna elephant (Loxodonta africana).

The African savanna elephant (Loxodonta africana) is the largest terrestrial animal on Earth and is found primarily in Southern and Eastern Africa. It is a hindgut, colonic fermenter and subsists on a diet of raw plant materials found in its grazing area. In this study the bacterial, archaeal and fungal populations of seven African savanna elephant fecal metagenomes were first characterized using amplicon sequencing. On the genus level it was observed that the p-1088-a5 gut group in the bacteriome, Methanocorpusulum and Methanobrevibacter in the archaeome and Alternaria, Aurobasidium, Didymella and Preussia in the mycome, predominated. Subsequently, metagenomic shotgun sequencing was employed to identify possible functional pathways and carbohydrate-active enzymes (CAZymes). Carbohydrate catabolic pathways represented the main degradation pathways, and the fecal metagenome was enriched in the glycohydroside (GH) class of CAZymes. Additionally, the top GH families identified - GH43, GH2, GH13 and GH3 - are known to be associated with cellulytic, hemicellulytic and pectolytic activities. Finally, the CAZymes families identified in the African savanna elephant were compared with those found in the Asian elephant and it was demonstrated that there is a unique repository of CAZymes that could be leveraged in the biotechnological context such as the degradation of lignocellulose for the production of second-generation biofuels and energy.

Short-read full-length 16S rRNA amplicon sequencing for characterisation of the respiratory bacteriome of captive and free-ranging African elephants (Loxodonta africana).

Hypervariable region sequencing of the 16S ribosomal RNA (rRNA) gene plays a critical role in microbial ecology by offering insights into bacterial communities within specific niches. While providing valuable genus-level information, its reliance on data from targeted genetic regions limits its overall utility. Recent advances in sequencing technologies have enabled characterisation of the full-length 16S rRNA gene, enhancing species-level classification. Although current short-read platforms are cost-effective and precise, they lack full-length 16S rRNA amplicon sequencing capability. This study aimed to evaluate the feasibility of a modified 150 bp paired-end full-length 16S rRNA amplicon short-read sequencing technique on the Illumina iSeq 100 and 16S rRNA amplicon assembly workflow by utilising a standard mock microbial community and subsequently performing exploratory characterisation of captive (zoo) and free-ranging African elephant (Loxodonta africana) respiratory microbiota. Our findings demonstrate that, despite generating assembled amplicons averaging 869 bp in length, this sequencing technique provides taxonomic assignments consistent with the theoretical composition of the mock community and respiratory microbiota of other mammals. Tentative bacterial signatures, potentially representing distinct respiratory tract compartments (trunk and lower respiratory tract) were visually identified, necessitating further investigation to gain deeper insights into their implication for elephant physiology and health.

Salmonellosis in elephants in managed care: report of 2 cases and literature review.

In animals, salmonellosis is seen typically as enteritis and/or septicemia. Subclinical infection also occurs, and outwardly healthy animals can serve as reservoirs of infection. Reports of salmonellosis in elephants are rare, limited to a few serovars, and the gross and microscopic lesions of enteric salmonellosis in this species have not been described in detail. We present here, in 2 elephants in managed care settings, cases of salmonellosis that resulted from infection by Salmonella enterica serovar Muenchen and S. enterica serovar Montevideo, serovars that have not been described previously as the cause of salmonellosis in elephants, to our knowledge. We also review the literature on salmonellosis in elephants. Animal A, an adult Asian elephant that was euthanized because of gastrointestinal hemorrhage, had multifocal, necrotizing, suppurative enterocolitis, and necrotizing gastritis. Animal B, an adult African elephant with chronic, recurrent colic, followed by death, had necrotizing typhlocolitis. The origin of infection was not determined in either case. The animals came from different facilities and did not have a common feed source. Previously reported cases of salmonellosis in elephants were caused by Salmonella Dublin, Salmonella Typhimurium, or Salmonella Enteritidis. The definitive diagnosis of salmonellosis is made based on compatible gross and microscopic lesions, coupled with the detection of Salmonella spp. in the affected tissues. Effective biosecurity should be adopted to minimize the risk of salmonellosis in elephants in managed care.

Potential diagnostic biomarkers for pulmonary tuberculosis in humans are not elevated in Mycobacterium tuberculosis culture-positive Asian elephants (Elephas maximus).

OBJECTIVE: To determine (1) if chemokine (C-X-C motif) ligand 1 (CXCL1), matrix metalloproteinase 8 (MMP8), interleukin-10 (IL-10), interferon-γ (IFN-γ), and tumor necrosis factor-α (TNF-α) can be detected in serum from Asian elephants, and (2) if their concentrations are significantly elevated in Mycobacterium tuberculosis (M.tb) culture-positive elephants compared to -negative elephants. CXCL1, MMP8, IL-10, IFN-γ, and TNF-α were recently identified as potential diagnostic biomarkers for pulmonary tuberculosis in experimental studies in animals and humans. Therefore, we hypothesized that they would be detectable and significantly elevated in M.tb culture-positive elephants compared to M.tb culture-negative elephants. SAMPLE: 101 Asian elephant serum samples, including 91 samples from 6 M.tb-negative elephants and 10 samples from 5 M.tb-positive elephants (none of which exhibited clinical signs of disease). M.tb status was determined by trunk wash culture. PROCEDURES: Commercially available ELISA kits were used to determine the concentrations of each biomarker in serum samples. RESULTS: Biomarker concentrations were below the limit of detection for the assay in 100/101 (99%) samples for CXCL1, 98/101 (97%) samples for MMP8, 85/101 (84%) samples for IL-10, 75/101 (74%) samples for IFN-γ, and 45/101 (45%) samples for TNF-α. Multiple M.tb culture-positive elephants did not have detectable levels of any of the 5 biomarkers. CLINICAL RELEVANCE: CXCL1, MMP8, IL-10, IFN-γ, and TNF-α were not elevated in M.tb culture-positive Asian elephants compared to M.tb culture-negative Asian elephants. This may be related to disease state (ie, clinically asymptomatic). More sensitive assays are needed to better understand the role of these biomarkers in M.tb infection in Asian elephants.

Understanding Mycobacterium tuberculosis complex in elephants through a One Health approach: a systematic review.

BACKGROUND: Mycobacterium tuberculosis complex (MTC) that causes the chronic infectious disease- tuberculosis (TB), often presents with a complicated epidemiological pattern where the transmission chain may include humans, domestic animals and wildlife, including elephants. TB has been reported globally in both captive and wild elephants. The One Health approach might be the most effective way of understanding the shared MTC infection dynamics in captive and wild animals like Asian elephants. This systematic review accumulates evidence on occurrence, transmission pathways, and preventive measures of TB in elephants from a One Health perspective. RESULTS: The prevalence of TB reported in elephant populations ranges from 0 to 23.33% and high prevalence's are reported for elephants that are in close proximity to infected humans. The risk of elephant to human infection transmission increased significantly with exposure duration and contact with infected elephants. Some studies described the plausible TB transmission to captive elephants from other animals (wild and domestic), suggesting inter- and intra-species transmission. The results of this systematic review based on 27 relevant published works, suggest three overarching interrelated transmission pathways for M. tuberculosis infections in Asian elephants- i) humans and elephants, ii) other animals (wild or domestic) and elephants and iii) unclear sources of infection. CONCLUSIONS: The progress made with new TB diagnostic tools provides multiple methods to choose from. However, lack of harmonization of TB testing in elephants and their human contacts remains a challenge to prevent TB in those animals. Routine TB screening among elephants and caretakers by setting up an occupational health program for early diagnosis of infection through combined efforts of public health, veterinary medicine, and occupational health experts is suggested. This implies the need for a One Health approach to elephant TB control. This review reveals the need for more research on Mycobacterium tuberculosis complex transmission pathways at the human-animal interface.

Comparative and functional analyses of fecal microbiome in Asian elephants.

Asian elephant is large herbivorous animal with elongated hindgut. To explore fecal microbial community composition with various ages, sex and diets, and their role in plant biomass degrading and nutrition conversation. We generated 119 Gb by metagenome sequencing from 10 different individual feces and identified 5.3 million non-redundant genes. The comprehensive analysis established that the Bacteroidetes, Firmicutes and Proteobacteria constituted the most dominant phyla in overall fecal samples. In different individuals, the alpha diversity of the fecal microbiota in female was lower than male, and the alpha diversity of the fecal microbiota in older was higher than younger, and the fecal microbial diversity was the most complex in wild elephant. But the predominant population compositions were similar to each other. Moreover, the newborn infant elephant feces assembled and maintained a diverse but host-specific fecal microbial population. The discovery speculated that Asian elephant maybe have start to building microbial populations before birth. Meanwhile, these results illustrated that host phylogeny, diets, ages and sex are significant factors for fecal microbial community composition. Therefore, we put forward the process of Asian elephant fecal microbial community composition that the dominant populations were built first under the guidance of phylogeny, and then shaped gradually a unique and flexible gut microbial community structure under the influences of diet, age and sex. This study found also that the Bacteroidetes were presumably the main drivers of plant fiber-degradation. A large of secondary metabolite biosynthetic gene clusters, and genes related to enediyne biosynthesis were found and showed that the Asian elephant fecal microbiome harbored a diverse and abundant genetic resource. A picture of antibiotic resistance genes (ARGs) reservoirs of fecal microbiota in Asian elephants was provided. Surprisingly, there was such wide range of ARGs in newborn infant elephant. Further strengthening our speculation that the fetus of Asian elephant has colonized prototypical fecal microbiota before birth. However, it is necessary to point out that the data give a first inside into the gut microbiota of Asian elephants but too few individuals were studied to draw general conclusions for differences among wild and captured elephants, female and male or different ages. Further studies are required. Additionally, the cultured actinomycetes from Asian elephant feces also were investigated, which the feces of Asian elephants could be an important source of actinomycetes.

Monitoring IgG against Mycobacterium tuberculosis proteins in an Asian elephant cured of tuberculosis that developed from long-term latency.

Tuberculosis (TB) is fatal in elephants, hence protecting elephants from TB is key not only in the conservation of this endangered animal, but also to prevent TB transmission from elephants to humans. Most human TB cases arise from long-term asymptomatic infections. Significant diagnostic challenges remain in the detection of both infection and disease development from latency in elephants due to their huge bodies. In this study, we assessed cryopreserved sera collected for over 16 years, from the first Japanese treatment case of elephant TB. Semi-quantification of IgG levels to 11 proteins showed high detection levels of 3 proteins, namely ESAT6/CFP10, MPB83 and Ag85B. The level of IgG specific to these 3 antigens was measured longitudinally, revealing high and stable ESAT6/CFP10 IgG levels regardless of onset or treatment. Ag85B-specifc IgG levels were largely responsive to onset or treatment, while those of MPB83 showed intermediate responses. These results suggest that ESAT6/CFP10 is immunodominant in both asymptomatic and symptomatic phases, making it useful in the detection of infection. On the other hand, Ag85B has the potential to be a marker for the prediction of disease onset and in the evaluation of treatment effectiveness in elephants.

DISPERSION OF AEROSOLIZED BACTERIA FROM ASIAN ELEPHANTS (ELEPHAS MAXIMUS).

Transmission of tuberculosis typically requires close and prolonged contact with an infected individual. However, several cases of transmission between elephants and from elephants to humans or other animals without direct contact or over long distances have been reported. Elephants have been shown to be capable of producing aerosolized bacterial droplets, suggesting a possible route of transmission that is magnified by the size and force of the elephant respiratory tract. To investigate the dispersion and viability of aerosolized bacteria generated from the elephant respiratory tract, a pre-existing model with a proxy organism was used. A six-stage Andersen sampler was used to detect the proxy organism, a commensal elephant respiratory bacterium, at different locations around an elephant barn at a zoo. The amount of proxy organism detected at various time points and distances from the elephants indicates they are capable of dispersing viable bacterial aerosols further than humans can. The concentration of these aerosols is dependent on proximity to the elephants and does not remain at a high level for prolonged periods of time. These findings support the model of aerosol-mediated transmission of bacteria from elephants and can be used to improve disease management practices and prevent the spread of pathogens from elephants in zoos and other facilities.

PREVALENCE OF SALMONELLA SPECIES, CLOSTRIDIUM PERFRINGENS, AND CLOSTRIDIUM DIFFICILE IN THE FECES OF HEALTHY ELEPHANTS (LOXODONTA SPECIES AND ELEPHAS MAXIMUS) IN EUROPE.

Pathogenic Salmonella spp., Clostridium perfringens, and Clostridium difficile have been reported to infect and cause severe enteritis and enterotoxemia in African (Loxodonta spp.) and Asian elephants (Elephas maximus). However, little information exists on whether healthy elephants carry and possibly shed these gastrointestinal organisms. This study was conducted to investigate the prevalence of all three bacteria in feces from healthy elephants in European zoos. Bacterial identification was performed by selective culture on fecal samples and a polymerase chain reaction (PCR) amplification protocol, on the basis of primers targeting the hilA gene (Salmonella spp.), the cpa gene (C. perfringens), and the tpi gene (C. difficile) from deoxyribonucleic acid extracted from elephant feces. The PCR protocol was validated prior to initiation of the investigation. Fecal samples collected from 50 African and 86 Asian elephants originating from 30 European zoologic institutions were investigated. The PCR validation revealed detection limits ranging from 104 to 106 colony-forming units per gram of feces of each gene. Only C. perfringens (one type A and two type E) was detected in the initial sampling (2.2%, three Asian elephants), whereas no Salmonella spp. or C. difficile was detected. At a follow-up sampling from C. perfringens-positive animals and relatives, 2 mo after the initial sampling, three animals were culture positive for Salmonella enterica spp. enterica. All positive samples were obtained with bacterial culture, whereas no PCR reactions were positive. Despite carrying these pathogens, all culture-positive animals were clinically healthy and did not develop signs of gastrointestinal disease during the study period. The findings indicate that prevalence of Salmonella spp., C. perfringens, and C. difficile in feces from healthy Asian and African elephants in Europe is very low.

Anthropogenic interferences lead to gut microbiome dysbiosis in Asian elephants and may alter adaptation processes to surrounding environments.

Human activities interfere with wild animals and lead to the loss of many animal populations. Therefore, efforts have been made to understand how wildlife can rebound from anthropogenic disturbances. An essential mechanism to adapt to environmental and social changes is the fluctuations in the host gut microbiome. Here we give a comprehensive description of anthropogenically induced microbiome alterations in Asian elephants (n = 30). We detected gut microbial changes due to overseas translocation, captivity and deworming. We found that microbes belonging to Planococcaceae had the highest contribution in the microbiome alterations after translocation, while Clostridiaceae, Spirochaetaceae and Bacteroidia were the most affected after captivity. However, deworming significantly changed the abundance of Flavobacteriaceae, Sphingobacteriaceae, Xanthomonadaceae, Weeksellaceae and Burkholderiaceae. These findings may provide fundamental ideas to help guide the preservation tactics and probiotic replacement therapies of a dysbiosed gut microbiome in Asian elephants. More generally, these results show the severity of anthropogenic activities at the level of gut microbiome, altering the adaptation processes to new environments and the subsequent capability to maintain normal physiological processes in animals.

Hypermucoviscous/hypervirulent and extensively drug-resistant QnrB2-, QnrS1-, and CTX-M-3-coproducing Klebsiella pneumoniae ST2121 isolated from an infected elephant (Loxodonta africana).

The rapid dissemination of extended-spectrum ß-lactamases (ESBLs)-producing Enterobacterales from different spheres worldwide over recent years has become a serious problem in both human and veterinary medicine. CTX-M-3-type ESBL has only been reported on few occasions, and in Brazil the blaCTX-M-3 gene has been identified only once in clinical strains. In this study, we aimed to molecularly characterize a hypermucoviscous (hm), hypervirulent (hv), and extensively drug-resistant (XDR) Klebsiella pneumoniae strain isolated from a lung tissue culture of an infected elephant. The A246 strain belonged to ST2121 and presented hm phenotype, hypervirulence-associated genes, and carried blaCTX-M-3 and plasmid-mediated quinolone resistance genes (qnrB2 and qnrS1) on an IncFII-IncQ1-IncM1 multireplicon plasmid (pA246-CTX-M-3, ∼ 162 kb). A novel genetic context of blaCTX-M-3, in which a 482-bp ISEcp1 was truncated by an IS26, was also harbored by pA246-CTX-M-3. Furthermore, in vivo experiments revealed that the hm/hv A246 strain killed 100 % of the Galleria mellonella larvae at 72 h post-infection. Our findings evidence the intercontinental dissemination of a rare K. pneumoniae ST2121 and the multidrug resistance IncFII-IncQ1-IncM1 plasmid. Therefore, to the best of our knowledge, this is the first report of an XDR K. pneumoniae coproducing CTX-M-3, QnrB2, and QnrS1 isolated from captive wild animals.

The Xpert MTB/RIF Ultra assay detects Mycobacterium tuberculosis complex DNA in white rhinoceros (Ceratotherium simum) and African elephants (Loxodonta africana).

The study describes the novel use of the Xpert MTB/RIF Ultra assay for detection of Mycobacterium tuberculosis complex (MTBC) DNA in samples from white rhinoceros (Ceratotherium simum) and African elephants (Loxodonta africana). Culture negative respiratory sample matrices were spiked to determine if the Ultra could detect MTBC DNA in rhinoceros and elephant samples. Rhinoceros bronchial alveolar lavage fluid (BALF) was found to have an inhibitory effect on the Ultra. In this study, the limit of detection (LOD) of M. tuberculosis H37Rv in all spiked animal samples were 2 CFU/ml compared to 15.6 CFU/ml for humans, while the LOD for M. bovis SB0121 was 30 CFU/ml compared to 143.4 CFU/ml for M. bovis BCG in humans. Screening was performed on stored tissue and respiratory samples from known MTBC-infected animals and MTBC DNA was detected in 92% of samples collected from six rhinoceros and two elephants. Conversely, 83% of culture-negative tissue and respiratory samples from uninfected animals tested negative on the Ultra. In conclusion, the Ultra assay appears to be a sensitive and rapid diagnostic test for the detection of MTBC DNA from tissue and respiratory samples collected from African elephants and rhinoceros. Furthermore, the Ultra assay could provide a new tool for the detection of MTBC in various sample types from other wildlife species.

Tuberculosis in elephants: Origins and evidence of interspecies transmission.

Tuberculosis (TB) is a devastating disease in elephants caused by either Mycobacterium tuberculosis or M. bovis. It is an ancient disease, and TB in elephants was first reported over two millennia ago in Sri Lanka. Outbreaks of TB worldwide, in captive and free-ranging elephant populations, have been recorded. Interspecies transmission of TB among elephants and humans has been confirmed in several geographic localities using spoligotyping, MIRU-VNTR analysis, and/or comparative genomics. Active surveillance of TB in wild and captive elephants and their handlers is necessary to prevent TB transmission at the elephant-human interface and to aid in the conservation of Asian and African elephants. In this review, we present an overview of diagnosis, reports of TB outbreaks in the past 25 years, TB in wild elephants, its transmission, and possible prevention and control strategies that can be applied at the elephant-human interface.

The VetMAX™ M. tuberculosis complex PCR kit detects MTBC DNA in antemortem and postmortem samples from white rhinoceros (Ceratotherium simum), African elephants (Loxodonta africana) and African buffaloes (Syncerus caffer).

BACKGROUND: Bovine tuberculosis and tuberculosis are chronic infectious diseases caused by the Mycobacterium tuberculosis complex members, Mycobacterium bovis and Mycobacterium tuberculosis, respectively. Infection with M. bovis and M. tuberculosis have significant implications for wildlife species management, public health, veterinary disease control, and conservation endeavours. RESULTS: Here we describe the first use of the VetMAX™ Mycobacterium tuberculosis complex (MTBC) DNA quantitative real-time polymerase chain reaction (qPCR) detection kit for African wildlife samples. DNA was extracted from tissues harvested from 48 African buffaloes and MTBC DNA was detected (test-positive) in all 26 M. bovis culture-confirmed animals with an additional 12 PCR-positive results in culture-negative buffaloes (originating from an exposed population). Of six MTBC-infected African rhinoceros tested, MTBC DNA was detected in antemortem and postmortem samples from five animals. The PCR was also able to detect MTBC DNA in samples from two African elephants confirmed to have M. bovis and M. tuberculosis infections (one each). Culture-confirmed uninfected rhinoceros and elephants' samples tested negative in the PCR assay. CONCLUSIONS: These results suggest this new detection kit is a sensitive screening test for the detection of MTBC-infected African buffaloes, African elephants and white rhinoceros.

Analysis of infant microbiota composition and the relationship with breast milk components in the Asian elephant (Elephas maximus) at the zoo.

The prevention of diseases through health control is essential at zoos. Here, we investigated the gut microbiota formation during infancy in an Asian elephant and compared the composition between infant and mother. Besides, we analyzed the components of breast milk and examined the correlation with the infant gut microbiota. Analysis revealed the gut microbiota of the infant contained high amount of Lactobacillales and its diversity was relatively low compared to that of the mother. We found several milk components, showed a positive correlation with the change of Lactobacillales. The present study revealed the mechanism of gut microbiota formation during infancy in an Asian elephant and provides important insights into the health control of Asian elephants in zoos.

Antiviral properties of extracts of Streptomyces sp. SMU 03 isolated from the feces of Elephas maximus.

Actinobacteria are historically and continued to be an important source for drug discovery. The annual epidemics and periodic pandemics of humans induced by influenza A virus (IAV) prompted us to develop new effective antiviral drugs with different modes of action. An actinobacterium of Streptomyces sp. SMU 03 was identified from the feces of Elephas maximus in Yunnan Province, China. By employing an H5N1 pseudo-typed virus drug screening system, the anti-IAV effect of the dichloromethane extracts (DCME) of this bacterium was investigated. DCME showed broad and potent activities against several influenza viruses, including the H1N1 and H3N2 subtypes and influenza B virus, with IC50 values ranging from 0.37 ± 0.22 to 14.44 ± 0.79 µg/mL. A detailed modes-of-action study indicated that DCME might interact with the HA2 subunit of hemagglutinin (HA) of IAV by interrupting the fusion process between the viral and host cells' membranes thereby inhibiting the entry of the virus into host cells. Furthermore, the in vivo anti-IAV activity test of DCME showed that compared with the no-drug treated group, the survival rates, appearances, weights, lung indices and histopathological changes were all significantly alleviated. Based on these results, the chemical constituent study of DCME was then investigated, from which a number of antiviral compounds with various structural skeletons have been isolated and identified. Overall, these data indicated that the DCME from Streptomyces sp. SMU 03 might represent a good source for antiviral compounds that can be developed as potential antivirus remedies.

Metagenomic Analysis of the Fecal Microbiomes of Wild Asian Elephants Reveals Microflora and Enzymes that Mainly Digest Hemicellulose.

To investigate the diversity of gastrointestinal microflora and lignocellulose-degrading enzymes in wild Asian elephants, three of these animals living in the same group were selected for study from the Wild Elephant Valley in the Xishuangbanna Nature Reserve of Yunnan Province, China. Fresh fecal samples from the three wild Asian elephants were analyzed by metagenomic sequencing to study the diversity of their gastrointestinal microbes and cellulolytic enzymes. There were a high abundance of Firmicutes and a higher abundance of hemicellulose-degrading hydrolases than cellulose-degrading hydrolases in the wild Asian elephants. Furthermore, there were a high abundance and a rich diversity of carbohydrate active enzymes (CAZymes) obtained from the gene set annotation of the three samples, with the majority of them showing low identity with the CAZy database entry. About half of the CAZymes had no species source at the phylum or genus level. These indicated that the wild Asian elephants might possess greater ability to digest hemicellulose than cellulose to provide energy, and moreover, the gastrointestinal tracts of these pachyderms might be a potential source of novel efficient lignocellulose-degrading enzymes. Therefore, the exploitation and utilization of these enzyme resources could help us to alleviate the current energy crisis and ensure food security.

OUTBREAK OF MYCOBACTERIUM TUBERCULOSIS IN A HERD OF CAPTIVE ASIAN ELEPHANTS ( ELEPHAS MAXIMUS): ANTEMORTEM DIAGNOSIS, TREATMENT, AND LESSONS LEARNED.

Tuberculosis (TB) was diagnosed in four Asian elephants ( Elephas maximus) in a zoo in the United States. The first case was detected by isolation of Mycobacterium tuberculosis during routine trunk wash (TW) culture testing of a herd of eight elephants. Retrospective antibody analyses revealed seroconversion 1 yr before diagnosis. Serological testing of the whole elephant herd identified two additional suspect bulls with detectable antibody, but which remained culture-negative and had no clinical signs of disease. In the following months, M. tuberculosis, identical to the isolate from the index case, was isolated from TW samples of these two elephants. A fourth elephant seroconverted nearly 4 yr after the first TB case was detected, and M. tuberculosis was isolated from a TW sample collected 1 mo later. All four infected elephants received anti-TB therapy. Two treated elephants were eventually euthanized for reasons unrelated to M. tuberculosis and found to be culture-negative on necropsy, although one of them had PCR-positive lung lesions. One infected animal had to be euthanized due to development of a drug-resistant strain of M. tuberculosis; this animal did not undergo postmortem examination due to risk of staff exposure. The fourth animal is currently on treatment. Serial serological and culture results of the other four herd mates have remained negative.

Mycobacterium caprae Infection in Captive Borneo Elephant, Japan.

In 2016, disseminated tuberculosis caused by Mycobacterium caprae was diagnosed in a captive Borneo elephant in Japan. The bacterium was initially identified from clinical isolates. An isolate collected during a relapse showed isoniazid monoresistance and a codon 315 katG mutation.