Acute, fatal Sarcocystis falcatula infection in rose-ringed parakeets (Psittacula krameri).

Sarcocystosis is an important avian disease that affects several intermediate host species. Birds not endemic from Americas, like Old World psittacine species, appear to be more susceptible to lethal infection than New World psittacine species. The aim of this study was to investigate the sudden death of rose-ringed parakeets (Psittacula krameri) in an exotic private parrot's aviary. Macroscopically, the most prevalent findings were severe lung congestion, slight superficial myocardial hemorrhagic lesions, enlarged liver and congestion of meningeal vessels. The initial diagnosis of sarcocystosis was made in all birds by microscopic observations of intravascular pulmonary schizonts, as well hepatitis, myocarditis, and nephritis. Immunohistochemistry for detection of Sarcocystis sp. antigen revealed an intense immunoreactivity in the lungs. Molecular identification of Sarcocystis falcatula were obtained by nested PCR and sequencing of amplified fragments of internal transcribed spacer 1 (ITS1) and three surface antigen-coding genes (SAG2, SAG3 and SAG4). SAG-based phylogenies showed a close relatedness of the isolate described here and S. falcatula previously detected in naturally infected native birds, which suggests that the isolates that affected ringnecks are a common isolate that circulates in Brazil.

SARS-CoV-2 Spillback to Wild Coatis in Sylvatic-Urban Hotspot, Brazil.

We tested coatis (Nasua nasua) living in an urban park near a densely populated area of Brazil and found natural SARS-CoV-2 Zeta variant infections by using quantitative reverse transcription PCR, genomic sequencing, and serologic surveillance. We recommend a One Health strategy to improve surveillance of and response to COVID-19.

Polyarteritis nodosa in a captive common wooly monkey (Lagothrix lagotricha) associated with intestinal necrosis, peritonitis, and sepsis.

Polyarteritis nodosa is an idiopathic necrotizing vasculitis that affects small to medium-sized arteries. We describe a case of polyarteritis nodosa in a captive common wooly monkey (Lagothrix lagotricha) associated with transmural intestinal necrosis and secondary peritonitis. This condition must be considered for differential diagnosis of segmental arteritis in neotropical primates.

A Survey of Diseases in Different Species of Wild, Captive, and Illegally Traded Birds in Brazil.

Native and exotic avian species can act as reservoirs of pathogens, including bacteria and viruses, with conservation and public health implications. A retrospective study on the diagnosis and frequency of diseases in wild and exotic avian species was conducted. The occurrence of particular diseases was associated with the type of captivity or the bird's origin. The investigation included macroscopic and microscopic descriptions and the molecular determination of the causative agent(s). Additional immunohistochemical (IHC) analysis, PCR, and genetic sequencing were conducted. A total of 243 cases were compiled for the study, mainly consisting of native wild species (39.1%) obtained from illegal trade. Primary infectious diseases, mainly parasitic (18.1%) and viral (17.7%), were the most common, although coinfections were substantial (18.1%) in birds rescued from trafficking. Fractures and neoplasms accounted for 3.7% and 3.3% of the cases, respectively. Parasitic and viral diseases were the most common in both exotic and wild birds. Chlamydia psittaci, a lethal and zoonotic bacterium, was an important cause of death, especially in native Psittaciformes. The recent detection of Psittacid alphaherpesvirus 5 (PsAHV 5) in exotic psittacines and the diagnosis of coinfections in trafficked birds highlight the importance of monitoring avian health to control potential pathogens that may endanger conservation efforts.

Genotyping of Toxoplasma gondii in a lethal toxoplasmosis outbreak affecting captive howler monkeys (Alouatta sp.).

BACKGROUND: Toxoplasmosis is a zoonotic disease that affects humans and warm-blooded animals. This study describes an outbreak of toxoplasmosis in howler monkeys (Alouatta sp.) and survival of capuchins (Sapajus apella), under the same environmental conditions. METHODS: Howler monkeys were submitted to post-mortem examination. Tissue samples were processed to histopathology and immunohistochemistry to detect lesions and tachyzoites of Toxoplasma gondii. Tissue samples were also frozen and submitted to PCR and genotyping of T. gondii. RESULTS: Typical lesions were observed in several organs including the liver, lymph node, and brain, with intralesional cysts and tachyzoites of T. gondii demonstrated by immunohistochemistry. T. gondii genomic sequences were amplified by PCR, and genotyping characterized the same T. gondii clone in all howler monkeys. CONCLUSIONS: Our results support the notion that some species of neotropical primates are highly susceptible to toxoplasmosis and the hypothesis that capuchins (S. apella) may be resistant.

MICROCOMPUTED TOMOGRAPHIC, MORPHOMETRIC, AND HISTOPATHOLOGIC ASSESSMENT OF CONGENITAL BONE MALFORMATIONS IN TWO NEOTROPICAL VIPERIDS.

Congenital malformations have been reported in all classes of vertebrates and may be a determinant of life span and survival. In reptiles, the incidence of congenital malformations can be associated with genetic and environmental causes, including pollution. The characterization of pathological processes involved in the development of congenital malformations of bone in snakes is rare in the literature, but is of great relevance in the field of reptile conservation and environmental health. We describe congenital bone lesions in 50 newborn jararaca (Bothrops jararaca) and 26 South American rattlesnakes (Crotalus durissus terrificus) born from wild-caught pregnant females in Southeastern Brazil. Lesions were evaluated by morphometric quantitative analysis, x-ray microtomography, and histopathologic descriptive analysis. Morphometric analysis showed that jararaca presented more severe axial lesions (kyphosis, scoliosis, and kyphoscoliosis) than rattlesnakes. Female rattlesnakes presented more severe axial lesions than did males. In rattlesnakes, spinal deformities were more frequently diagnosed in the caudal segment of the body. We present x-ray microtomographic assessments and images of malformed snakes (n=9) and characterized novel malformations, such as the agenesis of frontal, parietal, and supraoccipital bones in a jararaca specimen. Histopathologic findings included vertebral body fusion, myositis, coagulation necrosis, and disorganization of periaxial muscle fibers. The new methods and results presented in this study will be useful and informative for future research in pathology, teratology, embryology, and ecotoxicology in snakes.

Functional characterization of neotropical snakes peripheral blood leukocytes subsets: Linking flow cytometry cell features, microscopy images and serum corticosterone levels.

Reptiles are the unique ectothermic amniotes, providing the key link between ectothermic anamniotes fish and amphibians, and endothermic birds and mammals; becoming an important group to study with the aim of providing significant knowledge into the evolutionary history of vertebrate immunity. Classification systems for reptiles' leukocytes have been described by their appearance rather than function, being still inconsistent. With the advent of modern techniques and the establishment of analytical protocols for snakes' blood by flow cytometry, we bring a qualitative and quantitative assessment of innate activities presented by snakes' peripheral blood leukocytes, thereby linking flow cytometric features with fluorescent and light microscopy images. Moreover, since corticosterone is an important immunomodulator in reptiles, hormone levels of all blood samples were measured. We provide novel and additional information which should contribute to better understanding of the development of the immune system of reptiles and vertebrates.