CLINICAL FINDINGS OF DENTAL DISEASE AND POTENTIAL CONTRIBUTING FACTORS IN PYGMY SLOW LORISES (NYCTICEBUS PYGMAEUS) UNDER HUMAN CARE.

Dental disease is a common finding in pygmy slow lorises (Nycticebus pygmaeus) under human care, but the etiology is not fully understood. The small oral cavity in this species can make diagnosis of dental disease difficult. This retrospective study evaluated medical records and diet and husbandry protocols from 18 participating institutions with the objective of describing the signalment, clinical signs, physical exam findings, tooth type, tooth location, diagnostics used, and treatments performed to help guide care for dental disease. In addition, the study aimed to identify potential contributing factors to dental disease in this species. Of 59 animals with medical records evaluated, 42 (71.2%) had dental disease: 19 (44.2%) males, 20 (46.5%) females, and 3 (9.3%) without gender documented. Average age at onset of dental disease was 7.6 yr in males and 9 yr in females. Multiple lorises with dental disease (n = 12; 28.6%) had no premonitory clinical signs, and dental disease was found incidentally on examination. On dental examination, 30 lorises (71.4%) had evidence of gingivitis. In 13 cases skull radiographs were taken, but the majority of images (n = 8; 61.5%) were nondiagnostic for pathologic dental changes. A small proportion of cases with dental abnormalities (n = 4; 9.5%) were diagnosed using computed tomography. In total, 175 teeth were extracted from 31 patients; molars were the most frequently extracted tooth (n = 55; 31.4%). No substantial differences in diets were noted among many of the participating institutions, and not all slow lorises evaluated developed dental disease (n = 17; 28.8%). This retrospective study provides clinical findings on slow loris dental disease and guidance for the veterinary care and management of slow lorises under human care.

AN OUTBREAK OF FELINE INFECTIOUS PERITONITIS IN THREE RELATED SAND CATS (FELIS MARGARITA) IN HUMAN CARE.

Feline infectious peritonitis (FIP) is a systemic disease in felid species caused by infection with mutated forms of feline coronavirus (FCoV), and outbreaks can devastate exotic felid populations in human care. Feline infectious peritonitis was diagnosed in three of four related juvenile sand cats (Felis margarita) from a single institution over a 6-wk period. Case 1 was a 7-mon-old male found deceased with no premonitory signs. Case 2, an 8-mon-old male (littermate to Case 1), and Case 3, a 6-mon-old male (from a different litter with identical parentage), were evaluated for lethargy and anorexia 1 mon after Case 1. Both exhibited transient anisocoria and progressive lethargy, anorexia, and dehydration despite antibiotic and supportive treatment. Approximately 1 wk after initial presentation, Case 2 was humanely euthanized, and Case 3 was found deceased. Necropsy findings included intrathoracic and/or intra-abdominal lymphadenopathy (3/3 cases), bicavitary effusion (2/3), multifocal tan hepatic and intestinal nodules (1/3), and multifocal yellow renal nodules (1/3). Histologically, all cats had severe pyogranulomatous vasculitis in multiple organs, and the presence of FCoV antigen was confirmed using immunohistochemical staining. Next-generation sequencing of the virus from Case 3's affected kidney demonstrated ∼93% homology to the UG-FH8 virus, a serotype 1 feline alphacoronavirus isolated from Denmark. Future research will focus on comparative viral genomic sequencing with the goals of identifying potential sources of FCoV infection and identifying features that may have contributed to the development of FIP in this species.

The evolution of primate malaria parasites: A study on the origin and diversification of Plasmodium in lemurs.

Among the primate malaria parasites, those found in lemurs have been neglected. Here, six Plasmodium lineages were detected in 169 lemurs. Nearly complete mitochondrial genomes (mtDNA, ≈6Kb) and apicoplast loci (≈6Kb) were obtained from these parasites and other Haemosporida species. Plasmodium spp. in lemurs are a diverse clade that shares a common ancestor with other primate parasites from continental Africa. Time-trees for the mtDNA were estimated under different scenarios, and the origin of the lemur clade coincides with the proposed time of their host species' most recent common ancestor (Lemuridae-Indriidae). A time tree with fewer taxa was estimated with mtDNA + Apicoplast loci. Those time estimates overlapped but were younger and had narrower credibility intervals than those from mtDNA alone. Importantly, the mtDNA + Apicoplast estimates that the clade including the most lethal malaria parasite in humans, Plasmodium falciparum, may have originated with Homininae (African apes). Finally, the phylogenetic congruence of the lemurs and their parasites was explored. A statistically significant scenario identified four cospeciation, two duplications, four transfer (host-switches), and zero loss events. Thus, the parasite species sampled in lemurs seem to be radiating with their hosts.

HEALTH ASSESSMENT OF BLACK-AND-WHITE RUFFED LEMURS (VARECIA VARIEGATA) IN RANOMAFANA NATIONAL PARK, MADAGASCAR.

The Anthropocene is a major threat to biodiversity worldwide. Human pressures including climate change and emerging infectious diseases are presenting new challenges to wildlife, requiring vigilance and monitoring of wild populations to ensure their persistence. In order to monitor fluctuations in health, baseline data from long-term studies are required. Clinical laboratory data on 80 black-and-white ruffed lemurs (Varecia variegata), derived from the capture of 98 individuals spanning six field seasons are presented. Serum biochemical profiles showed variation between years that remained within published reference intervals for the species, with the exception of total bilirubin in 2008, and creatine kinase and chloride in 2019. Serum trace minerals and fat-soluble vitamin values also fluctuated between years and are within ranges seen in other lemur species. These results, combined with previously published data on ectoparasite load and population genetic diversity, suggest that the Mangevo ruffed lemur population is healthy and can provide important and valuable baseline data for comparisons moving forward.

BIOMEDICAL EVALUATION OF THE GOLDEN-CROWNED SIFAKA (PROPITHECUS TATTERSALLI) IN DARAINA, MADAGASCAR.

Complete medical examinations were performed on 25 wild golden-crowned sifaka (Propithecus tattersalli) from northeastern Madagascar. Each animal received a complete physical examination and weight, body temperature, heart rate, and respiratory rate were documented. Blood samples were collected for packed cell volume, estimated total white blood cell count, serum biochemical profile, fat-soluble vitamin analysis, trace mineral analysis, and Toxoplasma gondii serology. All animals examined were adults and determined to be in good health and body condition. No ectoparasites were observed. Fecal samples were collected for endoparasite examination and bacterial culture; while no endoparasites were observed, fecal samples from two females cultured positive for Bacillus cereus. One male lemur had a positive antibody titer to Toxoplasma gondii immunoglobulin G. These baseline health data provide an important foundation for continued monitoring of this critically endangered species.

ESTABLISHMENT OF ACUTE-PHASE PROTEIN AND SERUM PROTEIN ELECTROPHORESIS PRELIMINARY REFERENCE VALUES FOR PRONGHORN (ANTILOCAPRA AMERICANA).

Pronghorn (Antilocapra americana) are native to western North America and are found in 24 Association of Zoos and Aquariums (AZA)-accredited institutions. Acute-phase proteins (APP) are a broad class of proteins that are stimulated in response to inflammation and have been shown to be a sensitive measure of inflammation in equids and ruminants. In this study, blood samples from clinically normal free-ranging and captive populations of pronghorn were analyzed using assays for protein electrophoresis (EPH) and APP, including serum amyloid A (SAA) and haptoglobin (HP), to develop preliminary ranges to gauge potential differences between these populations. Additional samples were taken from clinically abnormal captive pronghorn with facial abscesses. By EPH measurements, albumin: globulin ratio mean and SE were significantly different (P <0.05) with 1.02 (0.08) for captive populations and 1.91 (0.05) for free-ranging populations. Total protein mean and SE were significantly different (P <0.05) for captive and free-ranging populations, respectively 5.6 (0.3) g/dl and 6.9 (0.1) g/dl. Mean and SD of SAA for captive pronghorn were 1.4 (3.2) mg/L, and were significantly different from the free-ranging population, which was below the limits of detection for (P <0.05). There was no difference in HP levels between these groups. In a case study of a pronghorn with facial abscesses, elevated levels of HP, but not SAA, suggested that HP maybe useful in certain disease states. Future studies should explore the use of these biomarkers as tools to monitor general health, prognosis, and subclinical disease.

Virus discovery reveals frequent infection by diverse novel members of the Flaviviridae in wild lemurs.

Lemurs are highly endangered mammals inhabiting the forests of Madagascar. In this study, we performed virus discovery on serum samples collected from 84 wild lemurs and identified viral sequence fragments from 4 novel viruses within the family Flaviviridae, including members of the genera Hepacivirus and Pegivirus. The sifaka hepacivirus (SifHV, two genotypes) and pegivirus (SifPgV, two genotypes) were discovered in the diademed sifaka (Propithecus diadema), while other pegiviral fragments were detected in samples from the indri (Indri indri, IndPgV) and the weasel sportive lemur (Lepilemur mustelinus, LepPgV). Although data are preliminary, each viral species appeared host species-specific and frequent infection was detected (18 of 84 individuals were positive for at least one virus). The complete coding sequence and partial 5' and 3' untranslated regions (UTRs) were obtained for SifHV and its genomic organization was consistent with that of other hepaciviruses, with one unique polyprotein and highly structured UTRs. Phylogenetic analyses showed the SifHV belonged to a clade that includes several viral species identified in rodents from Asia and North America, while SifPgV and IndPgV were more closely related to pegiviral species A and C, that include viruses found in humans as well as New- and Old-World monkeys. Our results support the current proposed model of virus-host co-divergence with frequent occurrence of cross-species transmission for these genera and highlight how the discovery of more members of the Flaviviridae can help clarify the ecology and evolutionary history of these viruses. Furthermore, this knowledge is important for conservation and captive management of lemurs.

MOOSE ( ALCES ALCES) MORTALITY ASSOCIATED WITH CAPRINE HERPESVIRUS 2 (CPHV-2) IN A ZOOLOGICAL COLLECTION.

Malignant catarrhal fever (MCF) can affect both domestic and wild artiodactyls. In a zoological setting, in which subclinical carriers and susceptible species are often housed in close proximity, the disease can prove fatal. This report describes a case of goat-associated MCF in a captive moose ( Alces alces). The diagnosis was confirmed by histopathology, which showed lymphocytic vasculitis in the brain and panuveitis, and by detection of caprine herpesvirus 2 DNA in tissues. Identical viral DNA sequences amplified from the clinically affected moose and from domestic, petting goats ( Capra aegagrus hircus) housed in the zoo suggest that the goats were the source for the virus transmutation. This is the first report, to our knowledge, of confirmed goat-associated MCF in any moose in North America and of the surveillance measures and procedures put in place to prevent additional spread of the disease.

Minerals in the foods and diet of diademed sifakas: Are they nutritional challenges?

Minerals, though needed in small quantities, are essential to metabolic processes, and deficiencies can seriously threaten health, reproduction and survival. Despite this, few studies have measured mineral composition of wild primate foods and fewer have quantified mineral intake. Here we measured the concentration of nine minerals in 75 foods of diademed sifakas (Propithecus diadema; five groups) in habitats with varying levels of disturbance at Tsinjoarivo and estimated daily intakes using focal-animal feeding data and intake rates over one year. For six minerals (Ca, P, Na, Fe, Zn, and Cu), mean concentrations in foods fell short of the National Research Council's (NRC) recommendations for captive primates. Concentrations were highest in lianas, herbs, and epiphytes, and hemiparasites had exceptionally high Na. Leaves tended to have higher concentrations than fruits or flowers, but overlap was extensive. Mineral concentrations in daily diets varied little seasonally, but absolute intakes (g/day) were higher in the abundant season, due to the increase in food ingested. Disturbed habitat groups' diets had higher mineral concentrations for five minerals, but this translated into increased intakes only for Cu, as these groups ate less food overall. Overall, comparisons with percentage-based NRC recommendations suggests deficiencies, but this is contradicted by: (1) the fact that mass-specific intakes exceeded human recommendations, and (2) the lack of observed signs of deficiency. Ongoing efforts to quantify mineral consumption across wild primate populations and better understanding requirements on both a percentage and absolute basis will help in understanding effects on food selection, managing primate habitats and formulating captive diets.

MANAGEMENT OF A REEVE'S MUNTJAC ( MUNTIACUS REEVESI) WITH SEIZURES USING LEVETIRACETAM.

This report describes the diagnosis and management of idiopathic epilepsy in a 4-yr-old intact female Reeve's muntjac ( Muntiacus reevesi). The patient was initially witnessed to have isolated paroxysmal events consistent with epileptic seizures (altered consciousness, lateral recumbency, tonic/clonic movement of limbs) lasting less than 3 min with an immediate return to normal consciousness. The seizure frequency increased to >3 seizures within 24 hr and phenobarbital 3 mg/kg orally every 12 hr was started. Because of continued epileptic seizures and low serum phenobarbital levels, the dose was increased until significant elevations of aspartate aminotransferase (AST) and alkaline phosphatase (ALP) were detected. Levetiracetam 40 mg/kg orally every 12 hr was initiated and the phenobarbital was weaned and discontinued. One breakthrough seizure has been witnessed in the 10 mo since starting levetiracetam.

BASELINE HEALTH AND NUTRITION EVALUATION OF TWO SYMPATRIC NOCTURNAL LEMUR SPECIES (AVAHI LANIGER AND LEPILEMUR MUSTELINUS) RESIDING NEAR AN ACTIVE MINE SITE AT AMBATOVY, MADAGASCAR.

Extractive industries can have significant impacts on ecosystems through loss of habitat, degradation of water quality, and direct impact on floral and faunal biodiversity. When operations are located in sensitive regions with high biodiversity containing endangered or threatened species, it is possible to minimize impact on the environment by developing programs to scientifically monitor the impact on resident flora and fauna species in the early phases of operation so that effects can be mitigated whenever possible. This report presents the baseline health, nutrition, and trace mineral evaluation for 33 Avahi laniger (Eastern wooly lemur) and 15 Lepilemur mustelinus (greater sportive lemur) captured and given complete health evaluations that included the measurement of fat-soluble vitamins and trace minerals in addition to routine complete blood counts, serum chemistries, and parasite evaluations. All lemurs appeared healthy on physical examination despite the presence of minor wounds consistent with interspecies aggression in some individuals. Serum chemistry values were within expected ranges for other lemur species; however, A. laniger erythrocytes were significantly smaller than those of L. mustelinus. Serum nickel values were markedly higher than expected in both species, and selenium, copper, and cobalt levels were higher in L. mustelinus compared with A. laniger at the study site, as well as values for I. indri or P. diadema reported from other locations. Endoparasites and ectoparasites were typical of those reported in other wild lemur species, but load and diversity varied between A. laniger and L. mustelinus despite inhabiting the same forest ecosystem. This baseline assessment provides the foundation for ongoing monitoring.

Blood transcriptomes reveal novel parasitic zoonoses circulating in Madagascar's lemurs.

Zoonotic diseases are a looming threat to global populations, and nearly 75% of emerging infectious diseases can spread among wildlife, domestic animals and humans. A 'One World, One Health' perspective offers us an ideal framework for understanding and potentially mitigating the spread of zoonoses, and the island of Madagascar serves as a natural laboratory for conducting these studies. Rapid habitat degradation and climate change on the island are contributing to more frequent contact among humans, livestock and wildlife, increasing the potential for pathogen spillover events. Given Madagascar's long geographical isolation, coupled with recent and repeated introduction of agricultural and invasive species, it is likely that a number of circulating pathogens remain uncharacterized in lemur populations. Thus, it is imperative that new approaches be implemented for de novo pathogen discovery. To this end, we used non-targeted deep sequencing of blood transcriptomes from two species of critically endangered wild lemurs (Indri indri and Propithecus diadema) to characterize blood-borne pathogens. Our results show several undescribed vector-borne parasites circulating within lemurs, some of which may cause disease in wildlife, livestock and humans. We anticipate that advanced methods for de novo identification of unknown pathogens will have broad utility for characterizing other complex disease transmission systems.

Ectoparasites of Propithecus diadema (Primates: Indriidae) With Notes on Unusual Attachment Site Selection by Haemaphysalis lemuris (Parasitiformes: Ixodidae).

An examination of ectoparasite loads in two populations of wild diademed sifakas, Propithecus diadema Bennett, yielded seven species-four mite species, a louse, a hippoboscid fly, and a leech. Prevalence of the tick Haemaphysalis lemuris Hoogstraal, the mites Liponyssella madagascariensis (Hirst) and Lemuralges propithecus Bochkov et al., and the louse Trichophilopterus babakotophilus Stobbe was quite high, at least 20%. H. lemuris was the most common ectoparasite in one population, while completely absent in a second one. When present, the most common attachment site for H. lemuris males was in the nares of their hosts.

Lemuralges propithecus sp. n. (Acariformes: Psoroptidae), an ectoparasite of the diademed sifaka Propithecus diadema (Primates: Indriidae).

A new species of the genus Lemuralges Fain, 1963 (Acariformes: Psoroptidae: Makialginae) is described from the Malagasy lemur Propithecus diadema (Bennett) (Primates: Indriidae) based on all postembryonic instars. This new species differs from the only known species in this genus, Lemuralges intermedius Fain, 1963, by the following features: both sexes of L. propithecus sp. n. show a pair of medioventral projections of the subcapitulum (vs without projections in L. intermedius) and the propodonotal shield is slightly ornamented (vs unornamented); in males the hysteronotal shield is completely covered by longitudinal striae (vs median part without striae), setae c2 are 120-140 µm long (vs 200-210 µm long), and femur III has a short transverse furrow dorsally (vs a longitudinal furrow); in females, setae h2 are, at least, 2 times shorter than h3 (vs slightly longer, or subequal to, h3), tibia IV has a ventro-apical projection (vs without projection). Larvae and protonymphs of the new species show some unique developmental delays. Female and male tritonymphs differ by their external morphology.

PLASMA ELECTROPHORETIC PROFILES IN THE EASTERN MASSASAUGA (SISTRURUS CATENATUS) AND INFLUENCES OF AGE, SEX, YEAR, LOCATION, AND SNAKE FUNGAL DISEASE.

The purpose of this study was to establish reference intervals of the protein electrophoretic fractions and the acute-phase proteins hemoglobin binding protein (as determined by the haptoglobin assay) and C-reactive protein (CRP) and assess any possible correlations between varying age class, sex, location (Illinois or Michigan), year, or presence of snake fungal disease (SFD). Banked plasma samples were assayed from 130 eastern massasaugas from 2009 to 2014 in Illinois and Michigan. Snakes from Michigan had higher total protein (mean: 5.50 g/dl), albumin/globulin ratio (0.42), albumin (1.59 g/dl), and gamma globulins (0.55 g/dl) than from snakes in Illinois (4.72 g/dl, 0.29, 1.03 g/dl, 0.38 g/dl, respectively). Snakes in Illinois (22.19 g/ml) had higher CRP than snakes in Michigan (10.89 mg/ml). Adults had higher gamma globulins (0.47 g/dl) than juveniles (0.28 g/dl). Males had higher alpha-2 globulins (0.98 g/dl) and CRP (21.4 mg/ml) than females (0.85, 11.6, respectively). There were no significant differences in absolute plasma proteins in SFD-positive snakes, but the percentage of gamma globulins was significantly higher in positive snakes. Future research in this area can now build on this data to determine changes in population health over time or due to specific environmental or disease threats.

Biomedical evaluation of Verreaux's sifaka (Propithecus verreauxi) from Kirindy Mitea National Park in Madagascar.

Evaluation of the health, prevalence, and incidence of diseases in wild populations is a critical component of wildlife management. In addition, the establishment of reference physiologic parameters can Verreaux's sifaka (Propithecus verreauxi) from Kirindy Mitea National Park, Madagascar, during two field captures incontribute to the assessment of population risks. Complete medical evaluations were performed on 33 wild June 2010 and June 2011. Each animal received a complete physical examination: weight, body temperature, heart rate, and respiratory rate were recorded, and ectoparasites collected. Blood samples were collected for complete blood cell count, differential white blood cell count, hemoparasite examination, serum biochemical profile, fat-soluble vitamin analysis, trace mineral analysis, and toxoplasmosis and viral serology. Fecal samples were collected for bacterial culture and endoparasite examination. Significant differences exist between age classes for neutrophil and lymphocyte count, alkaline phosphatase, and creatinine values. Parasites detected were Callistoura sp., Bertiella lemuriformis, and Dipetalonema petteri. This publication reports the first complete biomedical evaluation of the P. verreauxi and provides a basis for hematologic and biochemical comparisons of P. verreauxi in the wild.

Kinetics of viral loads and genotypic analysis of elephant endotheliotropic herpesvirus-1 infection in captive Asian elephants (Elephas maximus).

Elephant endotheliotropic herpesviruses (EEHVs) can cause fatal hemorrhagic disease in juvenile Asian elephants (Elphas maximus); however, sporadic shedding of virus in trunk washes collected from healthy elephants also has been detected. Data regarding the relationship of viral loads in blood compared with trunk washes are lacking, and questions about whether elephants can undergo multiple infections with EEHVs have not been addressed previously. Real-time quantitative polymerase chain reaction was used to determine the kinetics of EEHV1 loads, and genotypic analysis was performed on EEHV1 DNA detected in various fluid samples obtained from five Asian elephants that survived detectable EEHV1 DNAemia on at least two separate occasions. In three elephants displaying clinical signs of illness, preclinical EEHV1 DNAemia was detectable, and peak whole-blood viral loads occurred 3-8 days after the onset of clinical signs. In two elephants with EEHV1 DNAemia that persisted for 7-21 days, no clinical signs of illness were observed. Detection of EEHV1 DNA in trunk washes peaked approximately 21 days after DNAemia, and viral genotypes detected during DNAemia matched those detected in subsequent trunk washes from the same elephant. In each of the five elephants, two distinct EEHV1 genotypes were identified in whole blood and trunk washes at different time points. In each case, these genotypes represented both an EEHV1A and an EEHV1B subtype. These data suggest that knowledge of viral loads could be useful for the management of elephants before or during clinical illness. Furthermore, sequential infection with both EEHV1 subtypes occurs in Asian elephants, suggesting that they do not elicit cross-protective sterilizing immunity. These data will be useful to individuals involved in the husbandry and clinical care of Asian elephants.

Soft tissue sarcomas in 2 zoo-housed Alaskan moose.

Soft tissue sarcomas (STSs) are common well-described cutaneous neoplasms in many domestic species. Few cutaneous neoplasms have been reported in cervids, other than papilloma virus-induced benign cutaneous fibromas (BCFs). Two wild-caught Alaskan moose (Alces alces), housed at different North American zoos, were both presented with lameness and a mass. The gross appearance of each mass varied greatly; case 1 had a distinct, exophytic, ulcerated mass near the right carpal joint similar in appearance to a BCF, and case 2 had a pronounced swelling over the left hip. Based on histologic evaluation, both masses were diagnosed as STS. The clinical presentation of these masses included rapid growth and associated lameness; however, gross appearance was markedly different. Histopathology revealed characteristics typical of STS in other species, including spindle-shaped cells arranged in streaming sheets with ovoid nuclei. STS should be included as a differential diagnosis for moose with a cutaneous or subcutaneous soft tissue mass or swelling.

Large Comparative Analyses of Primate Body Site Microbiomes Indicate that the Oral Microbiome Is Unique among All Body Sites and Conserved among Nonhuman Primates.

The study of the mammalian microbiome serves as a critical tool for understanding host-microbial diversity and coevolution and the impact of bacterial communities on host health. While studies of specific microbial systems (e.g., in the human gut) have rapidly increased, large knowledge gaps remain, hindering our understanding of the determinants and levels of variation in microbiomes across multiple body sites and host species. Here, we compare microbiome community compositions from eight distinct body sites among 17 phylogenetically diverse species of nonhuman primates (NHPs), representing the largest comparative study of microbial diversity across primate host species and body sites. Analysis of 898 samples predominantly acquired in the wild demonstrated that oral microbiomes were unique in their clustering, with distinctive divergence from all other body site microbiomes. In contrast, all other body site microbiomes clustered principally by host species and differentiated by body site within host species. These results highlight two key findings: (i) the oral microbiome is unique compared to all other body site microbiomes and conserved among diverse nonhuman primates, despite their considerable dietary and phylogenetic differences, and (ii) assessments of the determinants of host-microbial diversity are relative to the level of the comparison (i.e., intra-/inter-body site, -host species, and -individual), emphasizing the need for broader comparative microbial analyses across diverse hosts to further elucidate host-microbial dynamics, evolutionary and biological patterns of variation, and implications for human-microbial coevolution. IMPORTANCE The microbiome is critical to host health and disease, but much remains unknown about the determinants, levels, and evolution of host-microbial diversity. The relationship between hosts and their associated microbes is complex. Most studies to date have focused on the gut microbiome; however, large gaps remain in our understanding of host-microbial diversity, coevolution, and levels of variation in microbiomes across multiple body sites and host species. To better understand the patterns of variation and evolutionary context of host-microbial communities, we conducted one of the largest comparative studies to date, which indicated that the oral microbiome was distinct from the microbiomes of all other body sites and convergent across host species, suggesting conserved niche specialization within the Primates order. We also show the importance of host species differences in shaping the microbiome within specific body sites. This large, comparative study contributes valuable information on key patterns of variation among hosts and body sites, with implications for understanding host-microbial dynamics and human-microbial coevolution.

Gut microbiota and age shape susceptibility to clostridial enteritis in lorikeets under human care.

BACKGROUND: Enteritis is a common cause of morbidity and mortality in lorikeets that can be challenging to diagnose and treat. In this study, we examine gut microbiota in two lorikeet flocks with enteritis (Columbus Zoo and Aquarium-CZA; Denver Zoo-DZ). Since 2012, the CZA flock has experienced repeated outbreaks of enteritis despite extensive diet, husbandry, and clinical modifications. In 2018, both CZA and DZ observed a spike in enteritis. Recent research has revealed that the gut microbiota can influence susceptibility to enteropathogens. We hypothesized that a dysbiosis, or alteration in the gut microbial community, was making some lorikeets more susceptible to enteritis, and our goal was to characterize this dysbiosis and determine the features that predicted susceptibility. RESULTS: We employed 16S rRNA sequencing to characterize the cloacal microbiota in lorikeets (CZA n = 67, DZ n = 24) over time. We compared the microbiota of healthy lorikeets, to lorikeets with enteritis, and lorikeets susceptible to enteritis, with "susceptible" being defined as healthy birds that subsequently developed enteritis. Based on sequencing data, culture, and toxin gene detection in intestinal contents, we identified Clostridium perfringens type A (CZA and DZ) and C. colinum (CZA only) at increased relative abundances in birds with enteritis. Histopathology and immunohistochemistry further identified the presence of gram-positive bacilli and C. perfringens, respectively, in the necrotizing intestinal lesions. Finally, using Random Forests and LASSO models, we identified several features (young age and the presence of Rhodococcus fascians and Pseudomonas umsongensis) associated with susceptibility to clostridial enteritis. CONCLUSIONS: We identified C. perfringens type A and C. colinum associated with lorikeet necrohemorrhagic enteritis at CZA and DZ. Susceptibility testing of isolates lead to an updated clinical treatment plan which ultimately resolved the outbreaks at both institutions. This work provides a foundation for understanding gut microbiota features that are permissive to clostridial colonization and host factors (e.g. age, prior infection) that shape responses to infection.