Coronaviruses (CoV) infect a wide variety of hosts, causing epidemics in humans, birds, and mammals over the years. Bats (order Chiroptera) are one of the natural hosts of the Coronaviridae family. They represent 40% of the total number of mammal species in the Pantanal, a biodiversity hotspot in South America. Given the recent SARS-CoV-2 pandemic, we investigated the presence of CoV in bats captured in the Brazilian Pantanal. Oral and rectal swabs collected in 2021 from 419 bats were analyzed using Pancoronavirus-nested PCR targeting the RNA-dependent RNA-polymerase (RdRp) gene. Orthocoronavirinae was detected in 16.7% (70/419) of the bats; nine samples were sequenced, confirming that Carollia perspicillata (4), Phyllostomus hastatus (2), Desmodus rotundus (1), Molossus rufus (1), and Myotis cf. nigricans (1) collected in buildings formally used by humans were infected by Alphacoronavirus genera. This is the first description of Alphacoronavirus in bats from the Pantanal. As they are natural reservoirs of CoVs, constant monitoring of bats is important to comprehend the epidemiology of emerging viruses, especially in the Pantanal biome.

We analyzed the influence of the season, the environment, and the sex, as well as the relation of body mass (BM) in the serum albumin (ALB), aspartate aminotransferase (AST), creatinine (C), creatine kinase (CK), phosphorus (P), total calcium (tCa), total protein (TP), urea (U), uric acid (UA), calcium:phosphorus ratio (Ca:P), and the globulin value (GV) of thirty individuals of Phrynops geoffroanus of the urban area of Cuiabá, Mato Grosso, Brazil. The modeling of biochemical parameters was performed using the Generalized Additive Models for Location, Scale and Shape (GAMLSS) to verify the influence of variables considered in this study on each of the biochemical parameters analyzed. The season influenced AST, CK, C, tCa, Ca:P and UA. The environment influenced tCa, Ca:P, U and UA. On the other hand, CK, tCa, P, Ca:P and U differed significantly between males and females. Regarding the BM, a relationship of this variable was observed with CK, C, tCa, P, U, UA and Ca:P. We concluded that the season, environment, sex, and body mass can influence the biochemical parameters of P. geoffroanus, and these factors should be routinely considered in the interpretation of laboratory results.

Canine distemper virus (CDV) is a serious and often fatal disease caused by Morbillivirus canis, which affects domestic dogs and wild carnivores, with case-fatality rates reaching up to 47%. The hemagglutinin (H) protein mediates viral adsorption and shows high genetic variability, making it a valuable molecular marker. This study aimed to detect and characterize the H gene of CDV strains from 14 dogs with fatal neurological disease in the Brazilian states of Mato Grosso and Rondônia. Brain tissue was tested via RT-PCR for the nucleocapsid gene, and positive samples were amplified for the H gene. Ten complete H-gene sequences were obtained. Phylogenetic analysis revealed two distinct clusters within the South America I/Europe lineage: one related to strains from Uruguay and Argentina (with residues 530G/549Y) and another related to Brazilian strains (530S/549Y). One sequence (MT8) showed an intermediate position in the haplotype network but clustered phylogenetically with Uruguay/Argentina-related strains. Most sequences carried 530S/549Y, a pattern linked to altered SLAM receptor usage in wildlife. These findings demonstrate the co-circulation of two CDV clusters in Central–Western Brazil, their regional and international genetic connectivity, and amino acid substitutions potentially influencing host adaptation and antigenicity.

Alphavirus madariaga (MADV), a member of the eastern equine encephalitis virus complex, is an emerging arbovirus in South America, with limited information regarding its occurrence and molecular characterization in equine populations. This study reports the detection and genetic characterization of MADV in equines from the state of Mato Grosso, Brazil. Two horses presenting acute neurological disease with a clinical course of approximately two days were evaluated. Histopathological examination revealed nonsuppurative meningoencephalomyelitis. Molecular screening for neurotropic viruses using TaqMan RT-qPCR assays was negative for rabies virus, EHV-1, WEEV, VEEV, WNV, and flaviviruses, while MADV was detected with Ct values of 27.9 and 31.4. Partial NS1 and E1 gene fragments were amplified and sequenced. Phylogenetic analyses based on both genes consistently placed the strain, named Santo Antonio, within the MADV genotype III clade, with strong support in the E1 analysis. The cases occurred in a peri-urban area located near Santo Antônio do Leverger, approximately 30 km from Cuiabá, highlighting a potential interface between sylvatic and human-modified environments. These findings provide molecular evidence of MADV circulation in central-western Brazil and association with equines disease. Our results reinforce the role of horses as sentinels for neurotropic arbovirus surveillance before reaching human population.

A parvovirose canina é uma afecção viral de grande relevância em cães devido a sua alta transmissibilidade e morbidade, apresentando sintomatologia e alterações hematológicas características. Apesar de diversos fatores como raça, idade e leucopenia serem citados por influenciarem no prognóstico, os resultados ainda são divergentes. Assim, buscou-se associações entre as características da população, a sintomatologia e o hemograma com a evolução clínica de cães com parvovirose. Foram analisados 69 cães positivos para parvovirose, com até 12 meses de idade atendidos pelo Hospital Veterinário da Universidade Federal do Mato Grosso. A idade média dos cães foi de 3,9 meses, sendo a maioria machos (52,2%), de raça definida (79,7%), vacinados (68,1%) e vermífugados (75,4%). Os sinais clínicos apresentados foram abdominalgia (56,5%), alterações nas fezes (84%1%), anorexia (89,9%), desidratação (73,9%), êmese (89,9%) e prostração (78,3%). A alteração hematológica mais frequente foi a leucopenia (62,8%). A maior parte dos cães sobreviveu à infecção (65,2%). Não houve associação entre a idade, o sexo, a raça e a vacinação ou vermifugação com o prognóstico. Entretanto, houve associação entre a evolução e a presença de leucopenia, demonstrando que cães com leucopenia possuem maior risco de óbito. A presença de monócitos ativados e linfócitos reativos apresentou associação com a evolução e indica um prognóstico favorável. Portanto, as alterações morfológicas juntamente com o leucograma trazem informações valiosas para o prognóstico e direcionamento da conduta clínica no tratamento de cães com parvovirose. Palavras-chave: Enterite Hemorrágica. Hemograma. Parvovírus. Sintomatologia. Abstract Canine parvovirus is a very important viral disease in dogs due to its high transmissibility and morbidity, presenting symptoms and characteristic hematological changes. Although several factors such as breed, age and leukopenia have been mentioned in the literature as influencing prognosis, the results are still divergent. Thus, we explore relationships between population data, symptomatology and hemogram with clinical outcome of dogs with parvovirus. Sixty nine dogs with parvovirus up to 12 months of age treated at the Veterinary Hospital of the Federal University of Mato Grosso were analyzed. The average age of the dogs was 3.9 months, and most of them were males (52.2%), full-blooded breed (79.7%), vaccinated (68.1%), and dewormed (75.4%). The clinical signs presented were abdominalgia (56.5%), changes in feces (84%1%), anorexia (89.9%), dehydration (73.9%), emesis (89.9%) and prostration (78.3%). The most frequent hematological alteration was leukopenia (62.8%). Most of the dogs survived the infection (65.2%). There was no association between age, sex, breed, and vaccination or deworming with the prognosis. However, leukopenia was associated with survival outcome, showiting that dogs with leukopenia have a higher risk of death. The presence of activated monocytes and reactive lymphocytes was associated with the outcome and indicates a favorable prognosis. Therefore, the morphological alterations together with the leukogram provide valuable information for the prognosis and direction of the clinical management in the treatment of dogs with parvovirus. Keywords: Clinical Outcome. Hemorrhagic Enteritis. Hemogram. Parvovirus. Symptomatology.