ABSTRACT
Understanding mortality causes is important for the conservation of endangered species, especially in small and isolated populations inhabiting anthropized landscapes where both natural and human-caused mortality may hinder the conservation of these species. We investigated the mortality causes of 53 free-ranging brown bears (Ursus arctos) found dead between 1998 and 2023 in the Cantabrian Mountains (northwestern Spain), a highly human-modified region where bears are currently recovering after being critically threatened in the last century. We detected natural traumatic injuries in 52.63% and infectious diseases in 39.47% of the 38 bears for which the mortality causes were registered, with 21.05% of these cases presenting signs of both infectious diseases and traumas. More specifically, almost 30% of the bears died during or after intraspecific fights, including sexually selected infanticide (10.53%). In addition, primary infectious diseases such as infectious canine hepatitis, distemper, clostridiosis and colibacillosis caused the death of 15.79% of the bears. The number of direct human-caused deaths (i.e., shooting, poisoning, snare) decreased over the study period. This study also reveals three new mortality causes triggered by pathogens, two of which-Clostridium novyi and verotoxigenic Escherichia coli-not previously described in ursids, and the other one, canine distemper virus, never reported in brown bears as cause of death. New management strategies for the conservation of Cantabrian bears, which are urgently needed due to the rapid expansion of the population, should consider the mortality causes described in this study and must promote further research to elucidate how the high prevalence of infectious diseases may threaten the current recovery of the population.
Subject(s)
Communicable Diseases , Ursidae , Humans , Animals , Communicable Diseases/veterinary , Spain/epidemiologyABSTRACT
Canine distemper virus (CDV) affects a huge diversity of domestic and wild carnivores, with increasing numbers of mortality events worldwide. The local cell-mediated immune response elicited against a natural infection is an important factor in determining the outcome of CDV infection. Therefore, the purposes of this study were to describe the local immune response within the central nervous systems (CNSs) of seven badgers naturally infected with CDV in Asturias (Atlantic Spain) and to determine the phenotype and distribution of microglial cells, T and B lymphocytes, and astrocytes in the foci of gliosis located in the thalamus and cerebellum using immunohistochemistry. The immunohistochemical assessment demonstrated the presence of Iba1-positive microglia and GFAP-positive astrocytes in the foci of gliosis, whereas T (CD3-negative) or B (CD20-negative) lymphocytes in those same lesions were absent. Our results also revealed that the badgers with natural CDV encephalitis presented lesions mostly located in the white matter of the thalamus and cerebellum, suggesting a CDV-specific tropism for the white matter of badger brains in those locations. The knowledge gained in the field of the immunopathogenesis of distemper disease affecting the CNSs of badgers could help to clarify CDV disease patterns in this species.
ABSTRACT
Preclinical Research The aim of the present study was to evaluate the antinoceptive interaction between the opioid analgesic, tapentadol, and the NSAID, ketorolac, in the mouse orofacial formalin test. Tapentadol or ketorolac were administered ip 15 min before orofacial formalin injection. The effect of the individual drugs was used to calculate their ED50 values and different proportions (tapentadol-ketorolac in 1:1, 3:1, and 1:3) were assayed in the orofacial test using isobolographic analysis and interaction index to evaluate the interaction between the drugs. The combination showed antinociceptive synergistic and additive effects in the first and second phase of the orofacial formalin test. Naloxone and glibenclamide were used to evaluate the possible mechanisms of action and both partially reversed the antinociception produced by the tapentadol-ketorolac combination. These data suggest that the mixture of tapentadol and ketorolac produces additive or synergistic interactions via opioid receptors and ATP-sensitive K+ channels in the orofacial formalin-induced nociception model in mice. Drug Dev Res 78 : 63-70, 2017. © 2016 Wiley Periodicals, Inc.
