Electrocutions in free-living black-tufted marmosets (Callithrix penicillata) in anthropogenic environments in the Federal District and surrounding areas, Brazil

Lethal dog attacks on adult rhesus macaques (Macaca mulatta) in an anthropogenic landscape

For nonhuman primates living in anthropogenic areas, predation by larger predators is relatively rare. However, smaller predators, such as free-ranging as well as domesticated dogs, can shape the socioecology of urban nonhuman primates, either directly by attacking and killing them or indirectly by modifying their activity patterns. Here, we describe three (two probably fatal) cases of dog attacks on adult rhesus macaques inhabiting an anthropogenic landscape in Northern India and the circumstances surrounding these incidents. We discuss the importance of considering human presence and intervention in dog-nonhuman primate relationships while studying nonhuman primate populations across anthropogenic gradients, and its potential influences on group social dynamics and transmission of zoonotic agents.

Successful management of pulmonary edema secondary to accidental electrocution in a young dog

BACKGROUND

Human records describe pulmonary edema as a life-threatening complication of electric shock. Successful management requires prompt recognition and intensive care. However, in companion animals, electrocutions are rarely reported, even though domestic environments are full of electrical devices and there is always the possibility of accidental injury. Therefore, it is important for veterinarians to know more about this condition in order to achieve successful patient outcomes.

CASE PRESENTATION

A 3-month-old male Labrador Retriever was presented with a history of transient loss of consciousness after chewing on a household electrical cord. On admission, the puppy showed an orthopneic position with moderate respiratory distress. Supplemental oxygen via nasal catheter was provided, but the patient showed marked worsening of respiratory status. Point-of-care ultrasound exams suggested neurogenic pulmonary edema due to electrical shock close to the central nervous system and increased B-lines without evidence of cardiac abnormalities. Mechanical ventilation of the patient was initiated using volume-controlled mode with a tidal volume of 9 to 15 ml/kg until reaching an end-tidal carbon dioxide ≤ 40 mm Hg, followed by a stepwise lung-recruitment maneuver in pressure-controlled mode with increases of the peak inspiratory pressure (15 to 20 cm H2O) and positive end-expiratory pressure (3 to 10 cm H2O) for 30 min, and return to volume-controlled mode with a tidal volume of 15 ml/kg until reaching a peripheral oxygen saturation ≥ 96%. Weaning from the ventilator was achieved in six hours, and the patient was discharged two days after admission without neurological or respiratory deficits.

CONCLUSIONS

We present a rather unusual case of a neurogenic pulmonary edema subsequent to accidental electrocution in a dog. Timely diagnosis by ultrasound and mechanical ventilation settings are described. Our case highlights that pulmonary edema should be considered a potentially life-threatening complication of electrical shock in small animal emergency and critical care medicine.

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.

Human and Non-Human Primate Coexistence in Argentina: Conflicts and Solutions

There are five different primate species inhabiting widely distinct ecoregions in Argentina. Each of them faces various threats in terms of conservation and conflicts that hamper their ability to coexist with human populations. We present here some of the drivers known to be the causes of conflicts between humans and primates in the southernmost area of distribution of Latin American primates. We focus our synthesis on two of the biggest sources of conflict: the effects of different anthropogenic disturbances, and human misconceptions concerning the role of primates in the ecosystem. In each section, we briefly characterize the conflicts worldwide and then provide specific cases and examples from Argentina. In the last part of the manuscript, we further describe some ongoing national and regional educational, research, and conservation approaches to mitigate those effects.

Case report: Urbanized non-human primates as sentinels for human zoonotic diseases: a case of acute fatal toxoplasmosis in a free-ranging marmoset in coinfection with yellow fever virus

Free-ranging non-human primates (NHP) can live in anthropized areas or urban environments in close contact with human populations. This condition can enable the emergence and transmission of high-impact zoonotic pathogens. For the first time, we detected a coinfection of the yellow fever (YF) virus with Toxoplasma gondii in a free-ranging NHP in a highly urbanized area of a metropolis in Brazil. Specifically, we observed this coinfection in a black-tufted marmoset found dead and taken for a necropsy by the local health surveillance service. After conducting an epidemiological investigation, characterizing the pathological features, and performing molecular assays, we confirmed that the marmoset developed an acute fatal infection caused by T. gondii in coinfection with a new YF virus South American-1 sub-lineage. As a result, we have raised concerns about the public health implications of these findings and discussed the importance of diagnosis and surveillance of zoonotic agents in urbanized NHPs. As competent hosts of zoonotic diseases such as YF and environmental sentinels for toxoplasmosis, NHPs play a crucial role in the One Health framework to predict and prevent the emergence of dangerous human pathogens.

Concentrations of iron and chromium in free-ranging common marmosets (Callithrix jacchus) from Pernambuco, Brazil

Common marmosets (Callithrix jacchus) are widely distributed in Northeast Brazil and often inhabit urban and peri-urban forest areas close to human settlements. Given its wide territorial distribution, its proximity to human populations, and its exposure to environmental degradations originating from urbanization, common marmosets have a high potential for environmental biomonitoring. The concentrations of iron (Fe) and chromium (Cr) were quantified in the liver, hair, and bone of 22 free-ranging common marmosets' bodies from nine cities from Pernambuco State, Brazil, using inductively coupled plasma optical emission spectrometry (ICP OES). The liver showed the highest concentrations of Fe and Cr (3773.2 ± 3715.8 mg/kg and 19.4 ± 41.6 mg/kg, respectively); the lowest concentration of Fe was detected in the bone (111.6 ± 97.6 mg/kg) and of Cr in the hair (3.3 ± 1.5 mg/kg). There was a moderate positive correlation between Fe and Cr in the liver (r = 0.64) and a high negative correlation for Cr between bone and hair (r = -0.65). This study demonstrated the bioaccumulation of Fe and Cr in hair, liver, and bone in common marmosets. The highest average concentration of Fe and Cr occurred in animals from Recife, Jaboatão dos Guararapes, and Paulista, respectively, the 1^st, the 2^nd, and the 5^th most populated cities in the state of Pernambuco. The presence of high concentrations of metals in animals from Recife and nearby cities can indicate alarming levels of environmental pollution in these locations.

Canopy bridges: preventing and mitigating anthropogenic impacts on mantled howler monkeys (Alouatta palliata palliata) in Costa Rica

Increasing levels of anthropogenic modification, degradation, and fragmentation of arboreal mammal habitats substantially influence wildlife movement and behavior. In Costa Rica, there has been a surge in infrastructure development in the past decade. This infrastructure puts wildlife at high risk of mortality from electrocution, vehicle collisions, falls, and attacks by domestic animals. To prevent and mitigate the mortality of arboreal animals, canopy bridges have been implemented in several parts of the country. In Playa Hermosa, Guanacaste, a coastal community, we implemented a canopy bridge project for mantled howler monkeys (Alouatta palliata palliata). For the first year of our study (2015-2016), we performed monthly three-day censuses and follows of all howler monkey groups. After the first five months of data collection, we identified 20 high-use arboreal pathways that would benefit from reinforcement with canopy bridges and installed camera traps in the pathways to verify their use outside of sampling periods. After use was verified, we installed canopy bridges at those 20 sites. We continued to identify high-use paths via group follows, ad libitum sightings from community members, and annual group censuses between 2018 and 2021 and installed an additional 91 bridges (N = 111 total). We also developed a system for community reporting of howler monkey injuries and fatalities and advocated for better insulation of electric cables, with 8341 m insulated between 2015 and 2021. Between 2015 and 2021, we saw the number of monkey groups grow from five to seven, group home ranges grow, the population grow from 59 to 99, and fatalities decrease from five to one annually. We conclude that the bridges likely contribute to howler monkey population growth via decreased fatalities and safer access to feeding resources and mates. Costa Rica is currently adopting legislation to make connectivity mitigation measures for wildlife mandatory in infrastructure development, making it a global leader.

Cases of fatal electrocution of the endangered Javan Gibbons (Mammalia: Primates: Hylobatidae) by power lines

Human-made structures are often deadly to wildlife. Power lines from electric poles can cause serious injury and even death of wildlife via electrocution, especially of arboreal primate species that can easily access power lines. Here, we reported three cases of wild ‘Endangered’ Javan Gibbons Hylobates moloch electrocuted by power lines along a road between a tea plantation and a village adjacent to Gunung Halimun-Salak National Park area, West Java, Indonesia. In all cases, the adult male Javan Gibbons jumped and grabbed a power line hanging at the edge of the forests and immediately died. Our case reports highlight that power lines can have a critically adverse effect on the survival of wild animals, particularly on highly arboreal species such as Javan Gibbons. We argue the need for mitigation plans (e.g., cable insulation) for power lines in areas at risk. Such areas should be determined based on wildlife habitat monitoring and the study of ranging behaviors, focusing on areas with high risks of electrocution. 

Non-thrombotic pulmonary embolism of brain, liver, or bone marrow tissues associated with traumatic injuries in free-ranging neotropical primates

From 2016 to 2019, Southeastern Brazil faced an outbreak of yellow fever (YF) affecting both humans and New World primates (NWP). The outbreak was associated with a marked increase in traumatic lesions in NWP in the affected regions. Non-thrombotic pulmonary embolization (NTPE) can be a consequence of massive traumatic events, and it is rarely reported in human and veterinary medicine. Here, we describe NTPE of the brain, liver, and bone marrow in free-ranging NWP, highlighting the epidemiological aspects of these findings and the lesions associated with this condition, including data on traumatic injuries in wild NWP populations during the course of a recent YF outbreak. A total of 1078 NWP were necropsied from January 2017 to July 2019. Gross traumatic injuries were observed in 444 marmosets (44.3%), 10 howler monkeys (23.2%), 9 capuchins (31.0%), 1 titi-monkey (50.0%), and 1 golden lion tamarin (33.3%). NTPE was observed in 10 animals, including 9 marmosets (2.0%) and 1 howler monkey (10.0%). NTPE was identified in the lung and comprised hepatic tissue in 1 case, brain tissue in 1 case, and bone marrow tissue in 8 cases. Although uncommon, it is important to consider NTPE with pulmonary vascular occlusion during the critical care of traumatized NWP. In addition, this study highlights the importance of conservational strategies and environmental education focusing on One Health, not only to protect these free-ranging NWP populations but also to maintain the efficacy of epidemiological surveillance programs.

Causes of death in neotropical primates in Rio Grande do Sul State, Southern Brazil

BACKGROUND

Anthropogenic disturbances are the main threats to nonhuman primates conservation, and infectious diseases may also play a key role in primate population decline. This study aimed to determine the main causes of death in neotropical primates.

METHODS

A retrospective study of post-mortem examinations was conducted on 146 neotropical primates between January 2000 and December 2018.

RESULTS

Conclusive diagnoses were obtained in 68.5% of the cases, of which 59 corresponded to non-infectious causes and 41 to infectious diseases. Trauma was the main cause of death (54/100), with anthropogenic stressors caused by blunt force trauma injuries (collision with vehicles) and puncture wound injuries associated with interspecific aggression (dog predation) were the most common factors. Other causes of death included bacterial diseases (27%), followed by parasitic diseases (12%), neoplasms (2%), and viral diseases (2%).

CONCLUSIONS

Free-ranging primates were mostly affected by non-infectious causes, while captive primates were by infectious conditions.

Pathology and One Health implications of fatal Leptospira interrogans infection in an urbanized, free-ranging, black-tufted marmoset (Callithrix penicillata) in Brazil

Leptospirosis is a zoonotic neglected disease of worldwide public health concern. Leptospira species can infect a wide range of wild and domestic mammals and lead to a spectrum of disease, including severe and fatal forms. Herein, we report for the first time a fatal Leptospira interrogans infection in a free-ranging nonhuman primate (NHP), a black-tufted marmoset. Icterus, pulmonary haemorrhage, interstitial nephritis, and hepatocellular dissociation were the main findings raising the suspicion of leptospirosis. Diagnostic confirmation was based on specific immunohistochemical and PCR assays for Leptospira species. Immunolocalization of leptospiral antigens and identification of pathogenic species (L. interrogans species) were important for better understanding the pathogenesis of the disease. One Health-related implications of free-ranging NHPs in anthropized areas and transmission dynamics of human and animal leptospirosis are discussed.

Eventos de electrocución de Aotus lemurinus (Primates: Aotidae) en los Andes Centrales de Colombia

Los primates que habitan en los ecosistemas de montaña de la cordillera de Los Andes en Colombia están expuestos a fuertes amenazas como consecuencia del desarrollo de la infraestructura y la transformación del uso del suelo en lo que corresponde a la región más densamente poblada de Colombia. Para el género Aotus cuyos hábitos son principalmente nocturnos las amenazas sobre sus poblaciones no han sido bien documentadas hasta la fecha, aunque especies como el mono nocturno andino (Aotus lemurinus) ha sido catalogado como Vulnerable a nivel nacional y global. En este estudio, compilamos registros recientes de individuos de Aotus lemurinus muertos por electrocución accidental en cuatro departamentos de los Andes Centrales de Colombia. Estos registros contribuyen al conocimiento previo sobre esta problemática a nivel nacional y resaltan la necesidad de formular e implementar estrategias de mitigación del riesgo de electrocución para esta y otras especies.