South American Rattlesnake (Crotalus durissus spp.) Envenomation in Dogs in the Semiarid Region of Brazil

Background:  South American rattlesnake (Crotalus durissus spp.) envenomation is rarely reported in small animals and livestock in Brazil. Minor swelling at the snakebite site, skeletal muscle, and renal damage, and severe neurological signs characterize the crotalic envenomation. This case report aims to present epidemiological, clinical, and pathological data of two cases of Crotalus durissus spp envenomation in dogs in the Northeast of Brazil.Cases: Envenomation by Crotalus durissus spp. was recorded in two dogs in Patos, State of Paraíba, Brazil. In Case 1, the dog presented flaccid paralysis, hyporeflexia, a deficit of cranial nerves, epistaxis, and gingival hemorrhages. Laboratory assay showed proteinuria, myoglobinuria, regenerative thrombocytopenia, and increased serum activities of creatine kinase (CK), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP). The dog was medicated with crotalic antivenom and wholly recovered from local and systemic clinical signs. In Case 2, the dog died and was detected fang marks at the ventral region of the left mandible (two small parallel perforations spaced 2.0 cm apart) at the snakebite site. Cyanosis of the oral cavity, congestion, and hemorrhages in several organs were observed at necropsy. Tubular nephrosis, muscular necrosis, hepatocytes swelling were observed. The owners witnessed snakebites, and the rattlesnakes (Crotalus durissus spp.) identified by the rattle at the end portion of the tail in both cases. Discussion: Natural South American rattlesnake envenomation presents complex clinical signs that makes diagnosis a challenge for veterinary practitioners. The criteria for the correct diagnosis and observed in the two dogs include witness of the snakebite, identification of the snake, detection of fang marks, clinical-pathological findings, and therapeutic response to treatment with specific anti-venom. The dog’s owners did not identify the subspecies of rattlesnakes; however, Crotalus durissus cascavella and Crotalus durissus collilineatus are the only species found in the Northeast region of Brazil. Crotoxin is the primary toxic component of South American rattlesnake, which induces neuromuscular blockage, and neurological signs (skeletal muscle flaccid paralysis, apathy, hyporeflexia, cranial nerve deficits). These clinical signs are similar to those observed in the two dogs. Respiratory distress, cyanosis, pulmonary edema, and hemorrhage are secondary to respiratory muscle paralysis and also detected in a dog (Case 2) with crotalic envenomation. Minor local swelling at the snakebite site,  myotoxicity observed in both dogs (high serum activities of CK and AST - Case 1), degeneration and necrosis of muscle fibers - Case 2), and fang marks observed in Case 2, strengthen the diagnosis of Crotalus durissus envenomation. Nephrotoxicity was also detected in both dogs (increased specific gravity of urine - Case 1 and myoglobin deposition and degeneration of renal epithelial tubular cells - Case 2). Coagulative disorders and hepatotoxicity are infrequently in domestic animals and humans with crotalic envenomation. High serum activities of ALP and ALT in Case 1, and swelling of hepatocytes in Case 2, suggest liver damage associated with the crotalic envenomation. The differential diagnosis of South American rattlesnake envenomation should be included in dogs with acute neuromuscular flaccid paralysis, associated or not with bleeding disorders, myoglobinuria, and acute kidney injury

Bronchopulmonary Aspergillosis Associated with Acute Myocardial Infarction in Dog

Background: Fungi of the genus Aspergillus are ubiquitous microorganisms of opportunistic character, of which animals and humans are continually exposed. Are described three main forms of aspergillosis in dogs: nasal, disseminated and bronchopulmonary. This form which is restricted to the lung parenchyma is considered rare in dogs. The aim of this paper is to report a case of pulmonary aspergillosis associated to acute myocardial infarction in a dog, focusing on epidemiological, clinical, pathological and immunohistochemical characteristics. Case: A male dog, 4-year-old, Pinscher, clinically presented dyspnea, anorexia, vomiting, concentrated urine and dark and mollifed faeces. On physical examination, there were congested oral and conjunctival mucosas, dehydration and petechiae in the outer ear. The animal died fve days after the clinical attendance and was sent for necropsy. The macroscopic lesions were restricted to the lung, heart and liver. There were multifocal areas of consolidation in the lung parenchyma and yellowish content in the trachea and bronchi lumen. The heart was rounded and with pale areas in the myocardium. Liver was discreet accentuation of the lobular pattern. Histologically the lesion was characterized by pyogranulomatous and necrotizing bronchopneumonia, multifocal to coalescing, moderate, associated with myriads of intralesional hyphae consistente with Aspergillus spp., associated with acute myocardial infarction. The hyphae weakly stained basophilic by hematoxylin and eosin were strongly impregnated by Grocott’s methenamine silver nitrate and showed strong immunolabelling of the cytoplasm, which were evidenced in brown. There were areas of acute myocardial infarction and hepatocellular degeneration and congestion in the liver, although fungal hyphae were not observed in these tissues. Discussion: The diagnosis of pulmonary aspergillosis was established based on the morphological and tinctorial characteristics of the agent and confrmed by immunohistochemistry. In this case, is not included in the clinical history any conditions that could promote immunosuppression, neither were observed morphological changes in the pathological examination which suggested other intercurrent diseases. It is likely that the dog has been exposed to the inhalation of large amounts of conidia for a long period of time, condition that favors the occurrence of the disease, even in immunocompetent animals. Probably were not evidenced severe respiratory clinical signs, that characterize the pulmonary impairment, due to the shortcourse of the disease. The pyogranulomatous and necrotizing inflammatory reaction is typical of fungal infection and was restricted to the lung parenchyma. The areas of coagulation necrosis observed in the myocardium are probably secondary to vascular injury caused by the fungi, with subsequent thromboembolism, ischemia and infarction. In Brazil, there are few reports of aspergillosis in dogs, have been reported the nasal and systemic forms. In the world literature, there are few reports about this bronchopulmonary form of the disease. Although uncommon, pulmonary aspergillosis should be considered in the differential diagnosis of diseases that affect the lower respiratory tract of dogs, as well as it’s systemic complications resulting from angioinvasive characteristic of the fungus, which in this case was determinant to the death of the animal. Keywords: Aspergillus, fungal disease, respiratory trac

NEOTROPICAL ALIEN MAMMALS: a data set of occurrence and abundance of alien mammals in the Neotropics

Biological invasion is one of the main threats to native biodiversity. For a species to become invasive, it must be voluntarily or involuntarily introduced by humans into a nonnative habitat. Mammals were among first taxa to be introduced worldwide for game, meat, and labor, yet the number of species introduced in the Neotropics remains unknown. In this data set, we make available occurrence and abundance data on mammal species that (1) transposed a geographical barrier and (2) were voluntarily or involuntarily introduced by humans into the Neotropics. Our data set is composed of 73,738 historical and current georeferenced records on alien mammal species of which around 96% correspond to occurrence data on 77 species belonging to eight orders and 26 families. Data cover 26 continental countries in the Neotropics, ranging from Mexico and its frontier regions (southern Florida and coastal-central Florida in the southeast United States) to Argentina, Paraguay, Chile, and Uruguay, and the 13 countries of Caribbean islands. Our data set also includes neotropical species (e.g., Callithrix sp., Myocastor coypus, Nasua nasua) considered alien in particular areas of Neotropics. The most numerous species in terms of records are from Bos sp. (n = 37,782), Sus scrofa (n = 6,730), and Canis familiaris (n = 10,084); 17 species were represented by only one record (e.g., Syncerus caffer, Cervus timorensis, Cervus unicolor, Canis latrans). Primates have the highest number of species in the data set (n = 20 species), partly because of uncertainties regarding taxonomic identification of the genera Callithrix, which includes the species Callithrix aurita, Callithrix flaviceps, Callithrix geoffroyi, Callithrix jacchus, Callithrix kuhlii, Callithrix penicillata, and their hybrids. This unique data set will be a valuable source of information on invasion risk assessments, biodiversity redistribution and conservation-related research. There are no copyright restrictions. Please cite this data paper when using the data in publications. We also request that researchers and teachers inform us on how they are using the data