Outbreak of type C botulism in captive wild birds

In late summer 2010, an outbreak of type C botulism affected the birds kept in a dam at a southern Brazilian zoo. A total of 14(10 black-necked swans, Cygnus melancoryphus; 3 Muscovy ducks, Cairina moschata; and 1 fulvous whistling-duck, Dendrocygna bicolor) out of 100 birds died after showing flaccid paralysis of the skeletal muscles characterized by general locomotion deficit, flight and swimming disorders, dropped neck, and severe dyspnea. Carcasses of dead birds (some infested by larvae of sarcophagus fly) scattered in the bird enclosure, and oxygen-free, organically rich mud and/or shallow standing waters present at the edges of the weir were identified as possible toxin sources. Postmortem examinations revealed no significant pathological changes. Epidemiologic and clinical findings indicated the diagnosis of type C botulism toxin, which was confirmed by mouse bioassay and seroneutralization.     

Magnetic resonance imaging diagnosis of intervertebral disc disease and myelomalacia in an American black bear (Ursus americanus)

A 23-yr-old black bear (Ursus americanus) was examined because of paralysis of unknown duration. The precise onset of clinical signs was unknown as a result of seasonal torpor. The bear was immobilized and transported to a university veterinary teaching hospital for further evaluation and treatment. Radiography revealed increased mineral opacity and ventral bridging across vertebral segments T8-11. Magnetic resonance imaging demonstrated dorsal and ventral compression of the spinal cord at T8-9. Given the bear's advanced age, the unknown duration of spinal cord compression, unknown presence of deep pain perception, and thus an unknown prognosis for surgical success, euthanasia was elected. Postmortem examination revealed severe spondylosis deformans from T7 to L3 and dorsal extradural extruded disc material in the area of T8-9. Histopathology demonstrated the dorsal horns of the spinal cord at T9 were replaced by foamy macrophages extending into the dorsal and lateral funiculi of the white matter compatible with focal, severe, chronic myelomalacia. This is the first report of intervertebral disc disease and myelomalacia diagnosed using MRI in a large carnivore.     

The anatomical distribution and antimicrobial susceptibility of yeast species isolated from healthy dogs

The aim of this work was to identify the predominant yeast species present at different anatomical sites in healthy dogs and to determine their in vitro antimicrobial susceptibility using a broth microdilution assay. Samples were collected from the preputial, vaginal, oral and perianal mucosae and the isolates cultured were identified according to their morphological characteristics and biochemical profile. Malassezia pachydermatis was the most commonly isolated yeast, followed by Candida parapsilosis, Candida tropicalis, Candida albicans, Saccharomyces cerevisiae and Rhodotorula spp.Minimum inhibitory concentrations of the azole derivatives ketoconazole, itraconazole and fluconazole against Candida spp. were 0.03–16 μg/mL, 0.06 to >16 μg/mL and 0.5–64 μg/mL, respectively and Candida isolates were sensitive to caspofungin and amphotericin B. Although all isolates of M. pachydermatis were sensitive to itraconazole, fluconazole, ketoconazole and amphotericin B, they were found to be resistant to caspofungin. The study has highlighted that Candida spp., M. pachydermatis, S. cerevisiae and Rhodotorula spp. are part of the normal canine surface microbiota and some of these organisms exhibit in vitro resistance to commonly used antimicrobials.     

Effect of seasonality and agricultural practices on occurrence of entomopathogenic nematodes and soil characteristics in La Rioja (Northern Spain)

The effects of seasonality and land management on entomopathogenic nematodes (EPNs) distribution and on soil characteristics were studied in natural areas and agricultural fields under organic and conventional management in La Rioja (Northern Spain). The population density of the native EPNs as well as air temperature, rainfall, soil fertility, soil moisture, and soil content of heavy metals were seasonally recorded over 2 consecutive years. The highest occurrence of EPNs was observed in autumn, followed by spring and summer. Agricultural management influenced the amount of soil organic matter, nutrients and heavy metals, as well as soil volumetric moisture and temperature, leading to statistical differences mainly between natural and agricultural sites, but also in some cases between different types of agricultural management. The usefulness of soil organic matter, C, N, P and K content, as well as the C/N, C/P and N/P ratios as indicators for differentiating conventional and organic crop management as well as the role of agricultural practices such as tillage and fertilizing is discussed.     

Characterization of aflatoxigenic and non-aflatoxigenic strains of <Emphasis Type="Italic">Aspergillus</Emphasis> section <Emphasis Type="Italic">Flavi</Emphasis> isolated from corn grains of different geographic origins in Brazil

Aflatoxins can cause great economic losses and serious risks to humans and animals health. The largest aflatoxin producers belong to Aspergillus section Flavi and can occur naturally in food commodities. Studies showed that molecular tools as well as the type of sclerotia produced by the strains could be helpful for identification of Aspergillus species and could be correlated with levels of toxin production. The purpose of this work was to characterize the genetic diversity using AFLP technique, the type of sclerotia and the ability of aflatoxin production by isolated strains from corn of different origins in Brazil, and to verify whether qPCR based on aflR and aflP genes is appropriate for estimating the level of aflatoxin production. All the 75 strains were classified as A. flavus and the AFLP technique showed a wide intraspecific variability within them. Regarding sclerotia production, 34% were classified as S and 66% as L type. Among the aflatoxin-producers, 52.8% produced aflatoxin B₁, while 47.2% aflatoxins B₁ and B₂. Statistical analysis showed no correlation between sclerotia production and aflatoxigenicty, and no correlation between the phylogenetic clusters and aflatoxin production. Concerning the relative expression of aflR and aflP, Pearson’s correlation test demonstrated low positive correlation between the expression of the aflR and aflP genes and the production of AFB₁ and AFB₂, but showed high positive correlation between aflR and aflP expression. In contrast to the other reference strains, A. oryzae ATCC 7282 showed no amplification of aflR and aflP. The results highlight the need for detection of reliable and reproducible markers with a high positive correlation with aflatoxin production.     

Development of osteochondrosis in Lusitano foals: A radiographic study

This study aimed to detect, by radiographic examination, the evolution of osteochondral lesions in the tarsocrural and femoropatellar joints of Lusitano foals. Within 1 month of age, 76.08% of foals had radiographic signs of osteochondrosis, but only 16.20% had lesions at 18 months. The radiographic signs resolved by 5 mo of age in most foals, but some cases that involved either joint, were not resolved until 12 mo of age. It is thought that the “age of no return” is 5 mo for the tarsocrural and 8 mo for the femoropatellar joint but this study demonstrated regression of osteochondral lesions in both joints of Lusitano foals up to 12 months of age.     

A solar collector for soil disinfestation

A solar collector to be used for disinfestation of substrates for plant propagation is described. At a high solar radiation intensity (more than 1 cal cm^–2 min^–1), one day of treatment was sufficient for disinfestation of soil infested withSclerotium rolfsii, Sclerotinia sclerotiorum, Fusarium solani f.sp.phaseoli orPythium aphanidermatum.Treatment of soil in the solar collector strongly reduced the total numbers of fungi, bacteria and actinomycetes. The nutrient status of the soil was only slightly changed and did not result in an effect on plant growth.     

PCR-based diagnosis for detection of Leishmania in skin and blood of rodents from an endemic area of cutaneous and visceral leishmaniasis in Brazil

The technique of polymerase chain reaction (PCR) associated to hybridization was used to screen 123 samples collected from wild and synanthropic rodents captured in a cutaneous and visceral leishmaniasis endemic area in the State of Minas Gerais, Brazil. The detection of Leishmania spp in naturally infected rodents is of fundamental importance for incriminating them as possible reservoir hosts of the diseases in Minas Gerais. A total of 62 specimens belonging to wild (Thrichomys apereoides, Oryzomys subflavus, Galea spixii, Bolomys lasiurus and Wiedomys pyrrhorhinos) and synanthropic (R. rattus) rodent species were captured in different ecotopes. Blood and skin samples were submitted for PCR analyses followed by molecular hybridization with specific probes for the three Leishmania-species complexes. Fifteen samples were found positive after PCR-hybridization and identified as follows: nine belonging to the L. mexicana complex, three to the L. braziliensis complex and three to the L. donovani complex. Positive PCR results were found in 11 out of the 61 (18%) blood samples and in four out of the 62 (6.4%) skin fragments screened. R. rattus and T. apereoides were the most abundant species in the area also presenting high prevalence of natural infection. The presence of parasite DNA belonging to L. braziliensis, L. mexicana and L. donovani complexes was confirmed in several individuals of a rodent species, R. rattus. This work is the first report of the detection of L. (L.) chagasi in a naturally infected T. apereoides. The utility of filter paper as a substrate for PCR analyses and the efficacy of the procedure associated to the hybridization is emphasized.     

Extradural spinal,bone marrow,and renal nephroblastoma

A 1-year-old, female intact Shetland sheepdog presented with acute onset of neurological signs. Physical examination revealed a large abdominal mass. Neurological examination revealed multifocal disease with neck pain, short-strided forelimbs, and hind-limb paresis with loss of tail and anal tone. Blood work, imaging techniques, cytopathology, and histopathology led to a diagnosis of renal, bone-marrow, and extradural spinal nephroblastoma. This report documents potential clinical and pathological manifestations of canine nephroblastoma that have not been previously reported.     

Systemic candidiasis in an apparently immunocompetent dog.

Members of the family Candida spp. are ubiquitous dimorphic fungi that normally inhabit the alimentary, upper respiratory, and genital mucosae of mammals. Cell-mediated immunity appears to be an important limitation to the pathologic spread of these fungi. Prolonged immunosuppression, cytotoxic chemotherapy causing neutropenia, diabetes mellitus, long-term glucocorticoid therapy, and prolonged antimicrobial therapy have resulted in an increased incidence of both localized and disseminated candidiasis. This report describes a systemic Candida spp. infection in a dog with no obvious underlying deficiency in host resistance. Cytopathology, histopathology, transmission electron microscopy, and immunohistochemical staining were used to determine the etiology of the causative agent.