Diagnostic features of metastatic endometrioid carcinoma in a captive black-tufted marmoset (Callithrix penicillata).

A captive marmoset developed metastatic endometrioid carcinoma (EnC), a rare uterine tumor in non-human primates (NHPs). The neoplasm showed marked microscopical malignant and tubulopapillary aspects, immunopositivity for pan-cytokeratin, CK7, estrogen receptor, and a high mitotic index (Ki-67). These features may contribute to the diagnosis and therapeutics of EnC in NHPs.

Staphylococcus spp. as part of the microbiota and as opportunistic pathogen in free-ranging black-tuffed marmosets (Callithrix penicillata) from urban areas: Epidemiology, antimicrobial resistance, and pathology.

BACKGROUND: Marmosets (Callithrix sp.), including black-tuffed marmosets (C. penicillata), are neotropical primates that can be highly adapted to urban environments, especially parks and forested areas near cities. Staphylococcus spp. are part of the microbiota of many different hosts and lead to opportunistic severe infection. Isolates from wild animals can be resistant to antimicrobial drugs. However, there are a few studies that evaluated Staphylococcus spp. in neotropical primates. The goal of this study was to evaluate Staphylococcus spp. isolated from free-ranging black-tuffed marmosets. METHODS: Marmosets were captured in six urban parks. After sedation, skin and rectal swabs and feces were sampled. Staphylococcus spp. isolates were identified by MALDI-ToF and their antimicrobial susceptibility was determined. RESULTS: Over 30% of captured individuals were positive for Staphylococcus spp., and S. aureus was the most isolated species followed by Mammaliicoccus (Staphylococcus) sciuri. With the exception of the marmoset subjected to necropsy, none of the other had lesions, which supports that notion that Staphylococcus spp. are members of the microbiota, but also opportunistic pathogens. Most isolates were susceptible to all antimicrobials tested; however, one isolate of S. epidermidis was resistant to multiple antimicrobials (penicillin, cefoxitin, ciprofloxacin, clindamycin, and erythromycin). We considered S. aureus as the main staphylococci to colonize black-tuffed marmosets. CONCLUSIONS: Black-tuffed marmosets can be colonized by several Staphylococcus species, most frequently by S. aureus, and the majority of isolates were sensible to the antimicrobials tested. One S. epidermidis isolate was considered multidrug resistant.

Morphometry and skeletopy of kidneys and renal vessels in marmoset (Callithrix spp.).

BACKGROUND: Marmosets, Callithrix spp, are small New World monkeys that have gained importance as an experimental animal model for human. Despite its use, information on its renal morphometry, vascularization, and location are limited. Therefore, this study will supply basic anatomy for applied studies and for comparative anatomy. METHODS: Fifty cadavers of Callithrix spp were collected on highways from the Atlantic Forest biome, identified and injected with a 10% formaldehyde solution. Later, the specimens were dissected and the measurements and topography of the kidneys and renal vessels were recorded. Both left and right kidneys were significantly larger in females. RESULTS: In the specimens studied, the average body length was 20.00 ± 2.46 cm in males and 20.50 ± 1.98 cm in females (p = .43). The kidneys of the Callithrix spp. were symmetrical in shape and resembled a "bean." They were also pale brown with a smooth surface. In males, the most frequent location of the right kidney was at the L1-L2 level (92%), while the location of the left kidney was between L2 and L3 (76%). In females, the most frequent location of the right kidney was at the L1-L2 level (56%), while the location of the left kidney was between L2 and L3 (32%) (Table 1). However, in seven (28%) males and nine (36%) females, the kidneys were at the same level. CONCLUSIONS: In both sexes, there was a positive and significant linear correlation between body length and kidney length. Regardless of the variable location of the kidneys in both sides and in either sexe, the right kidney was always located more cranially than the left, similar to observations in other non-human primates.

Post-mortem diagnosis of human rabies in SARS-CoV-2 coinfected patient with minimally invasive autopsy in northeastern Brazil.

INTRODUCTION: Human rabies (HR) is a lethal zoonotic disease caused by lyssaviruses with increase in the number of cases post-coronavirus disease 2019 (COVID-19) pandemic. METHODOLOGY: We report a case of human rabies in a patient from a rural area of Ceará, northeastern Brazil in 2023, who was bitten by a white-tufted-ear marmoset (Callithrix jacchus jacchus). The patient was co-infected with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and was diagnosed by minimally invasive autopsy (MIA). RESULTS: MIA offers many advantages related to biosafety, and speed of sample acquisition; and markedly reduces disfigurement of the body compared with complete autopsy. It is a great alternative in COVID-19 patients. CONCLUSIONS: New methods such as MIA are a promising tool for diagnosis, and have the potential to improve family cooperation and support rabies surveillance.

Detection of rabies virus in Callithrix penicillata (Geoffroy, 1812) in Montes Claros, Minas Gerais State, Brazil.

This report describes the occurrence of the rabies virus in two species of wild animals in the urban area of Montes Claros (MOC), Minas Gerais State, Brazil, in May 2023. The virus has been detected in frugivorous chiropterans (Artibeus sp) and marmosets (Callithrix penicillata). This is the first notified case of the rabies virus in the species C. penicillata in the urban area of MOC. Our findings show that the rabies virus is circulating in the urban area of MOC; therefore, permanent preventive measures must be adopted to avoid infection of other animals and humans.

Neuronal Stability, Volumetric Changes, and Decrease in GFAP Expression of Marmoset (Callithrix jacchus) Subcortical Visual Nuclei During Aging.

The physiological aging process is well known for functional decline in visual abilities. Among the components of the visual system, the dorsal lateral geniculate nucleus (DLG) and superior colliculus (SC) provide a good model for aging investigations, as these structures constitute the main visual pathways for retinal inputs reaching the visual cortex. However, there are limited data available on quantitative morphological and neurochemical aspects in DLG and SC across lifespan. Here, we used optical density to determine immunoexpression of glial fibrillary acidic protein (GFAP) and design-based stereological probes to estimate the neuronal number, total volume, and layer volume of the DLG and SC in marmosets (Callithrix jacchus), ranging from 36 to 143 months of age. Our results revealed an age-related increase in total volume and layer volume of the DLG, with an overall stability in SC volume. Furthermore, a stable neuronal number was demonstrated in DLG and superficial layers of SC (SCv). A decrease in GFAP immunoexpression was observed in both visual centers. The results indicate region-specific variability in volumetric parameter, possibly attributed to structural plastic events in response to inflammation and compensatory mechanisms at the cellular and subcellular level. Additionally, the DLG and SCv seem to be less vulnerable to aging effects in terms of neuronal number. The neuropeptidergic data suggest that reduced GFAP expression may reflect morphological atrophy in the astroglial cells. This study contributes to updating the current understanding of aging effects in the visual system and stablishes a crucial foundation for future research on visual perception throughout the aging process.

Analysis of palmprints and soleprints of black-tufted marmosets (Callithrix penicillata): are there similarities to humans?

Friction ridges are important and unique biometric features that have been studied in fingerprint science since antiquity and used for human identification. This study aimed to analyze palmprints and soleprints of Callithrix penicillata, including the description of flexion creases, regions, minutiae classification, and delta counting, in order to evaluate the uniqueness of these data and feasibility of using this information as an identification method. Palmprints and footprints were collected using commercial fingerprint ink on A4 size paper. Following image digitalization using the GIMP (2.10.14) image editing program, regions and flexion creases were identified. A total of 600 minutiae were classified in females (288 palms and 312 soles) and 732 in males (360 palms and 372 soles), and all deltas were counted. It was possible to identify three main inconstant flexion creases, in both palmprints and soleprints, with different distribution and orientation when compared to those in humans. Less variety in the types of minutiae and differences in the distribution of deltas were found when compared to human studies. In addition, the hypothesis of non-coincident characteristics in each sample was confirmed.

Contribution of ultrasound examination in diagnosing platynosomiasis and correlation with macro and microscopic findings in callitrichids kept under human care.

BACKGROUND: Platynosomiasis in non-human primates kept under human care causes chronic disease of the bile ducts and liver, which initially presents with nonspecific signs and can culminate in the death of the animal. Diagnosing this disease is a challenge, and an ultrasound examination can be an excellent tool when it is suspected. METHODS: This study describes the ultrasound findings from 57 marmosets with suspected infection by Platynosomum sp., the correlated hepatobiliary changes, and the anatomopathological findings that confirmed the occurrence of platynosomiasis. RESULTS: In six marmosets (one C. aurita, two C. jacchus, and three Callithrix sp.), Platynosomum infection was confirmed macroscopically (presence of adult trematodes in the gallbladder) and microscopically (adults, larvae, and eggs in histological examinations and eggs in bile and feces). These findings were compatible with the hepatobiliary changes and with images suggestive of parasitic structures in ante-mortem assessments. CONCLUSION: Ultrasound examination demonstrated its usefulness within the clinical routine for investigating this parasitosis.

Labor of a free-living buffy-tufted marmoset (Callithrix aurita) at a Wildlife Rehabilitation Center in southeastern Brazil.

Callithrix aurita is an endangered small primate endemic to the Atlantic Forest. The present work reports the labor of a free-living C. aurita, through observation of its length and offspring viability. A conservative treatment was used to maintain fetal viability, in view of the species conservation importance.

Group membership, not diet, structures the composition and functional potential of the gut microbiome in a wild primate.

The gut microbiome has the potential to buffer temporal variations in resource availability and consumption, which may play a key role in the ability of animals to adapt to a broad range of habitats. We investigated the temporal composition and function of the gut microbiomes of wild common marmosets (Callithrix jacchus) exploiting a hot, dry environment-Caatinga-in northeastern Brazil. We collected fecal samples during two time periods (July-August and February-March) for 2 years from marmosets belonging to eight social groups. We used 16S rRNA gene amplicon sequencing, metagenomic sequencing, and butyrate RT-qPCR to assess changes in the composition and potential function of their gut microbiomes. Additionally, we identified the plant, invertebrate, and vertebrate components of the marmosets' diet via DNA metabarcoding. Invertebrate, but not plant or vertebrate, consumption varied across the year. However, gut microbiome composition and potential function did not markedly vary across study periods or as a function of diet composition. Instead, the gut microbiome differed markedly in both composition and potential function across marmosets residing in different social groups. We highlight the likely role of factors, such as behavior, residence, and environmental heterogeneity, in modulating the structure of the gut microbiome. IMPORTANCE: In a highly socially cohesive and cooperative primate, group membership more strongly predicts gut microbiome composition and function than diet.

Choosing the best way: how wild common marmosets travel to efficiently exploit resources.

While foraging, animals have to find potential food sites, remember these sites, and plan the best navigation route. To deal with problems associated with foraging for multiple and patchy resources, primates may employ heuristic strategies to improve foraging success. Until now, no study has attempted to investigate experimentally the use of such strategies by a primate in a context involving foraging in large-scale space. Thus, we carried out an experimental field study that aimed to test if wild common marmosets (Callithrix jacchus) employ heuristic strategies to efficiently navigate through multiple feeding sites distributed in a large-scale space. In our experiment, we arranged four feeding platforms in a trapezoid configuration with up to 60 possible routes and observe marmosets' decisions under two experimental conditions. In experimental condition I, all platforms contained the same amount of food; in experimental condition II, the platforms had different amounts of food. According to the number and arrangement of the platforms, we tested two heuristic strategies: the Nearest Neighbor Rule and the Gravity Rule. Our results revealed that wild common marmosets prefer to use routes consistent with a heuristic strategy more than expected by chance, regardless of food distribution. The findings also demonstrate that common marmosets seem to integrate different factors such as distance and quantity of food across multiple sites distributed over a large-scale space, employing a combination of heuristic strategies to select the most efficient routes available. In summary, our findings confirm our expectations and provide important insights into the spatial cognition of these small neotropical primates.

Helminths of Wied's marmoset (Callithrix kuhlii (Coimbra-Filho, 1985) (Primates: Callitrichidae)) from the Atlantic Forest, Southern Bahia State, Brazil.

Callithrix kuhlii is present in forest mosaics, edge habitats, and abandoned fields in the Atlantic Forest. In Bahia and Minas Gerais. This study aimed to identify helminths from C. kuhlii and relate them to the clinical data, weights, and indices of the liver and gonads. Necropsies were performed on 13 adult marmosets that were run over on the BA-001 highway. A principal component analysis (PCA) was conducted to describe the relationships between the variables investigated. Fifty-one helminths were collected from 30.77% (4/13) of the marmosets analyzed. Helminths were classified based on their morphological and morphometric characteristics. Primasubulura jacchi (Marcel, 1857), Platynosomum illiciens (Dougherty, 1946), and Prosthenorchis confusus (Dougherty, 1946) were the species identified, with prevalence rates of 7.69%, 7.69%, and 15.38%, respectively. In addition, this is a new host record of P. confusus. The two main axes of the PCA explained a high variability (PCA=67.7%), indicating reduced weight and indices of the organs of parasitized animals. This study expands the knowledge on parasites of C. kuhlii and its vulnerability to parasites, contributing to constructing an epidemiological profile of environmental health.

Parasites and Viruses in Callithrix in Brazil.

PURPOSE: As a result of environmental imbalances of anthropogenic origin, the potential for transmission of parasites and viruses between different primates, including humans, might increase. Thus, parasitic studies have great relevance to primatology, which motivated us to conduct a literature review to synthesize the information available in American primates of the Callithrix genus. METHODS: We carried out the bibliographic search on the main groups of parasites (protozoa, helminths, arthropods, ectoparasites) and viruses found in Callithrix in Brazil in search platforms and consider all manuscript that appeared in search engines, published between the years 1910 and December 2022. In each selected article, the following information was recorded: the host species; parasite taxa; scientific classification of the parasite; host habitat (free-living, captive); diagnostic technique; state; and bibliographic reference. Data were tabulated and arranged in a parasite-host table. RESULTS: Some endemic genera, such as Callithrix, are widely distributed geographically across Brazil and have characteristics of adaptation to different habitats due to their flexibility in diet and behavior. These factors can make them subject to a greater diversity of parasites and viruses in the country. Here, we identified 68 parasitic taxa, belonging to the clades protozoa (n = 22), helminths (n = 34), ectoparasites (n = 7), and viruses (n = 5). Out of this total, 19 have zoonotic potential. Of the six existing marmoset species, Callithrix jacchus was the most frequent in studies, and Callithrix flaviceps did not have reports. All regions of the country had occurrences, mainly the Southeast, where 54% of the cases were reported. In 46% of the reported parasites and viruses, it was not possible to identify the corresponding species. CONCLUSION: We conclude that in part of the works the identification methods are not being specific, which makes it difficult to identify the species that affects Callithrix spp. Furthermore, the studies present geographic disparities, being concentrated in the southeast of the country, making it impossible to have a more uniform analysis of the findings. Thus, it is observed that information about parasites and viruses is incipient in the genus Callithrix in Brazil.

Phylogenetic analysis reveals a new introduction of Yellow Fever virus in São Paulo State, Brazil, 2023.

Yellow Fever (YF) is a viral arbovirosis of Public Health importance. In Brazil, surveillance is focused mainly on detecting epizootic events of Platyrrhini. Herein, we compared the detection and phylogenetic analysis of YF virus in two neotropical primates (NTP), a Callithrix detected in the previous epidemic period (2016-2020), and a Callicebus nigrifons, showing a new introduction of YF in 2023. This paper illustrates the importance of joint actions of laboratory and field teams to ensure quick response to Public Health emergencies, such as the intensification of vaccination of susceptible human populations.

Salivary alpha-amylase stress reactivity in advanced-aged marmosets (Callithrix jacchus): Impacts of cognitive function and oral health status.

Salivary alpha-amylase (sAA) is an enzyme found in saliva and is considered a noninvasive biomarker for sympathetic nervous system activity. While a wide range of sAA activity in response to stress has been reported in nonhuman primates, the effects of stress on sAA activity in common marmosets are still unknown. We tested the hypothesis that advanced age and cognitive function may have an impact on stress-related sAA reactivity in marmosets. Thirteen marmosets (nine males and five females) had saliva samples collected during a stressful condition (manual restraint stress) at two different time points, with a 60-min interval. On the next day, the animals underwent the object recognition test (ORT, a type of cognitive test), and then oral examinations. The animals were categorized into two age groups: old (10-13 years), and very old (15-22 years). Irrespective of age, sAA levels showed a significant difference between T1 (mean 2.07 ± 0.86 U/mL) and T2 samples (mean 1.03 ± 0.67 U/mL), with higher values observed at T1 (p < 0.001). The intra-assay coefficients of variation (CV) for low and high sAA concentrations were 10.79% and 8.17%, respectively, while the interassay CVs for low and high sAA concentrations were 6.39% and 4.38%, respectively. Oral health issues were common but did not significantly impact sAA levels. The ORT indicated that the animals could recognize an object placed in the cage 6 h after familiarization. In conclusion, all marmosets showed a higher sAA concentration in the first saliva sample as compared to the second saliva sample collected 1 h later, indicating adaptation to stress. No significant differences in sAA levels were observed between sexes, ORT performance, or oral health. Our results indicate that autonomic responsivity and cognitive (memory) functions were preserved even in very old marmosets.

Toxoplasmosis outbreak caused by north American genotypes in captive black-tufted marmosets in southern Brazil.

In this study, we describe an outbreak of toxoplasmosis in an enclosure of five Callithrix penicillata in Southern Brazil. The marmosets were found dead and submitted to necropsy and histopathology. Liver, spleen, and lungs were frozen and sent for polymerase chain reaction (PCR) and nested-PCR-restriction fragment length polymorphism (RFLP) genotyping of Toxoplasma gondii. Necropsy revealed a liver with a lobular pattern, along with diffusely congested lungs, spleen, and kidneys, and hemorrhage in the mesenteric lymph nodes. Mild-to-moderate, multifocal, necrotic hepatitis and splenitis, multifocal lymphoplasmacytic myocarditis, and moderate, diffuse necrohemorrhagic lymphadenitis were observed. T. gondii tachyzoites were in all the organs mentioned. The detected strains were closely related with the isolates TgWtdUs10, TgSoUs39, and TgShUs2, which were originally found in non-primate species all in the United States of America. This is an unprecedented report of North American strains causing mortality in captive individuals of the species Callithrix penicillata in the Southern Brazil.

Traumatic chylothorax in urbanized free-ranging black-tufted marmosets (Callithrix penicillata).

After fatal traumatic injuries, three urbanized free-ranging marmosets developed a milky white or pink-white thoracic alkaline effusion with high specific gravity, triglyceride levels, and predominance of small lymphocytes. Chylothorax is an uncommon thoracic fluid accumulation in animals and humans and has not been reported in free-ranging non-human primates.

Dilated cardiomyopathy phenotype in Callithrix penicillata (E. Geoffroy, 1812): Case report.

Dilated cardiomyopathy (DCM) is a disease of the heart muscle diagnosed by alterations resulting from ventricular systolic dysfunction with enlargement of the heart chambers, which is still underdiagnosed in non-human primates. This report is the first case of the DCM phenotype diagnosed by echocardiography and confirmed by necropsy in Callithrix penicillata.

First report of spontaneous hepatic fibrosarcoma in a white-tufted marmoset (Callithrix jacchus) kept in captivity.

Reports of sarcomas in nonhuman primates are scarce and, specifically, primary hepatic sarcomas are rare, as in humans. This is the first report of an aggressive hepatic fibrosarcoma in a young adult Callithrix jacchus. The final postmortem diagnosis was obtained by means of immunohistochemical analysis, which confirmed the tumor histogenesis.

Impact of human created environments in the pathogenic potential and antimicrobial resistance of staphylococci from wild neotropical primates in Brazil.

The non-human primate (NHP) Leontopithecus rosalia is an endangered species native of Brazil and lives in forest fragments with different levels of contact with humans (natural, private and urban). Other NHPs - Callithrix spp. - were introduced by humans and co-exist and interact with the native species in these forests. To evaluate if living in or close to human-modified environments could constitute a risk for L. rosalia, we compared the prevalence, genetic background, antibiotic susceptibility and virulence gene content of staphylococci collected from the native and the introduced species from different forest fragments. We found that presence in human-dominated environments increased the colonization rate of L. rosalia with Mammaliicoccus sciuri (former Staphylococcus sciuri) from 18 % to 85 % (p = 0.0001) and of Callithrix spp with Staphylococcus aureus from 6 % to 100 % (p = 0.0001). According to molecular typing data obtained differences probably resulted from dissemination of these bacterial species from the invader NHP species and from humans. Changes in microbiota were paralleled by an increase in the prevalence of Panton-Valentine Leukocidin gene and in resistance to beta-lactams, macrolides and/or lincosamides as exposure to human environment increased. In particular, erythromycin resistance in S. aureus from Callithrix spp. increased from 0 % to 50 % and resistance rate to at least one antibiotic in coagulase-negative staphylococci species from L. rosalia increased from 13 % to 56 % (p = 0.0003). Our results showed that contact of native animal species with human-created environments increased the content of antimicrobial resistant and pathogenic bacteria on their commensal microbiota, which ultimately can impact on their health. IMPORTANCE: Endangered animal species are vulnerable to environmental alterations and human activities have been repeatedly identified as factors driving drastic changes in the natural landscape. It is extremely important to monitor changes in the environment surrounding protected species, because this could lead to early detection of any potential threats. In this study, we found that the contact of L. rosalia - a protected non-human primate from Brazil - with human environments is related to changes in their commensal microbiota. These included an increase in the number of pathogenic and antibiotic resistant bacteria, which have a higher potential to cause infections that are more difficult to treat. We provided evidence for the harmful impact human contact has on L. rosalia. Also, our results suggest that monitoring of commensal microbiota of protected animal species might be a useful way of sensing the risks of protected species to human exposure.