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81.
Jos Diomedes Barbosa Carlos Magno C. de Oliveira Marcos Dutra Duarte Gabriela Riet-Correa Paulo Vargas Peixoto Carlos Hubinger Tokarnia 《Journal of Equine Veterinary Science》2006,26(9):393-398
The clinical and pathological aspects of a neurological disease observed in 16 horses in Pará, Amazonia, Brazil, are presented. The symptoms were mainly motor incoordination, paresis of the tongue, somnolence, difficulties in apprehension, chewing and swallowing of food, as well as instability and standing with abducted members. The clinical course was subacute or chronic and in most cases was not fatal. Postmortem examination performed in one already very sick, euthanized animal, did not show significant macroscopic lesions; histopathological examination revealed slight edema and degenerative alterations of a few axons, mainly in the medulla oblongata. In all pastures where horses were affected, plenty of bamboo had been eaten, probably because of scarcity of pasture. By feeding large amounts of fresh bamboo leaves of this region, in different growing stages, to three horses (horse 1, 47 g/kg/d for 30 days; horse 2, 10 g/kg/d for 60 days; horse 3, 18 g/kg on the first day, and 31 g/kg/d for 6 more days)—the animals ate the leaves unassisted—it was possible to reproduce nervous symptoms essentially identical to those observed in the natural disease 24 to 72 hours after the first feeding of the plant. In spite of continuous administration of the plant, intensity of the clinical signs did not increase. Based on field observations and comparison of the clinical and pathological pictures seen in the natural and experimental disease, the described illness can be concluded to be caused by the ingestion of large amounts of the leaves of Bambusa vulgaris f. vulgaris. 相似文献
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The value of molecular expression of KIT and KIT ligand analysed using real‐time polymerase chain reaction and immunohistochemistry as a prognostic indicator for canine cutaneous mast cell tumours 下载免费PDF全文
T. A. Costa Casagrande L. M. de Oliveira Barros H. Fukumasu B. Cogliati L. M. Chaible M. L. Z. Dagli J. M. Matera 《Veterinary and comparative oncology》2015,13(1):1-10
This study investigated the correlation between KIT gene expression determined by immunohistochemistry and real‐time polymerase chain reaction (RT‐PCR) and the rate of tumour recurrence and tumour‐related deaths in dogs affected with mast cell tumour (MCT). Kaplan–Meier curves were constructed to compare tumour recurrence and tumour‐related death between patients. The log‐rank test was used to check for significant differences between curves. KIT‐I, KIT‐II and KIT‐III staining patterns were observed in 9 (11.11%), 50 (61.73%) and 22 (27.16%) tumours, respectively. Tumour recurrence rates and tumour‐related deaths were not associated with KIT staining patterns (P = 0278, P > 0.05), KIT (P = 0.289, P > 0.05) or KIT ligand (P = 0.106, P > 0.05) gene expression. Despite the lack of association between KIT staining pattern and patient survival time, the results suggest a correlation between aberrant KIT localization and increased proliferative activity of MCTs. RT‐PCR seems to be a sensible method for quantitative detection of KIT gene expression in canine MCT, although expressions levels are not correlated with prognosis. 相似文献
85.
Galiza GJ Garcia HA Assis AC Oliveira DM Pimentel LA Dantas AF Simões SV Teixeira MM Riet-Correa F 《Veterinary parasitology》2011,182(2-4):359-363
Here, we report an outbreak of Trypanosoma vivax-induced trypanosomosis in Brazilian hair sheep on a farm in Paraíba state, a non-endemic region in northeastern Brazilian. Of 306 total sheep, 240 showed clinical signs and 216 died. Clinical signs included anorexia, lethargy, anemia, rough hair coat, weight loss, submandibular edema, abortion, and in some cases, neurological signs such as head pressing, lateral recumbence, paddling movements and muscle tremors. T. vivax was identified by blood smear analysis and polymerase chain reaction (PCR). At necropsy, animals exhibited watery blood, pale tissue coloring, and the presence of liquid in the peritoneal cavity and pericardial sac. Histologically, nonsuppurative myocarditis and meningoencephalitis with areas of malacia were observed. After treatment, no parasites were detected by blood smear analysis or PCR. Cattle and buffalo that remained in the same pasture were also infected but presented with asymptomatic infections. Epidemiological data suggest that T. vivax was introduced to the farm and the susceptible flock by buffalos that were asymptomatic carriers of the infection; T. vivax was most likely transmitted by Tabanus spp. bites and also iatrogenically. 相似文献
86.
Paulo Oliveira Dilia Menezes Martin Jones Manuel Nogales 《Biological conservation》2006,130(4):538-548
This study was conducted over a two year period in the north west of Madeira Island (Macaronesian Atlantic Islands, Portugal). It investigates the relationship between fruiting patterns in the indigenous forest and the use by the Madeira laurel pigeon of forest habitats and cultivated areas. Habitat use observations were carried out using line-transects in forest sites where the availability of fruit (the most important element of the diet) was assessed. The use of agricultural fields was measured indirectly by the assessment of the damage caused to crops. The findings provided strong evidence that bird movements and shifts in abundance are related to fruit usage and availability. The use of fruits is mostly opportunistic but when many species are available, selection was observed. From an ecological perspective, our findings indirectly confirm a high concordance between pigeon diet, studied by microhistological techniques, and habitat use. The use of crops also seems to be mostly opportunistic and is governed by the birds’ movements within the adjacent forest. It is hypothesised that fruit phenology will influence the use of agricultural areas only to the extent that it governs such movements; there is no strong evidence that crops are attacked only when the availability of natural foods is low. Our results suggest that the current management strategy for the forest is adequate for the conservation of this pigeon but that the conservation value of forest edges should be redefined. It is also proposed that crop damage may be reduced by identifying the proximate factors, which lead to the use of specific fields. 相似文献
87.
Is risk consistent across tier‐based harvest control rule management systems? A comparison of four case‐studies 下载免费PDF全文
Catherine M Dichmont André E Punt Natalie Dowling José A A De Oliveira Lorne R Little Miriana Sporcic Elizabeth Fulton Rebecca Gorton Neil Klaer Malcolm Haddon David C Smith 《Fish and Fisheries》2016,17(3):731-747
There can be substantial differences in data quality and quantity among fished species. Consequently, the quality and type of assessments can also vary substantially. However, all species, especially those that are targeted, need to be managed. Several jurisdictions have developed hierarchical tier systems that categorize stocks based on, for example, the data available for assessment purposes and/or the extent to which quantities on which management advice is based can be estimated. Four case‐studies (Australia's Southern and Eastern Scalefish and Shark Fishery, the USA west coast groundfishery, the USA Alaskan crab fishery and EU fisheries) are used to contrast the types of hierarchical tier systems available, and to assess the extent to which each system constrains risk to be equivalent among the tiers (termed risk equivalency). Only the Australian system explicitly aims to achieve risk equivalency. However, this intent has not been fully operationalized. Our review reveals that best practice is not to define tiers simply on data availability, but also on what the assessments based on those data are capable of estimating. In addition, clearly differentiating the quantification of uncertainty from how decision‐makers wish to address that uncertainty would simplify justification of buffers (the gap between the assessment‐produced target catch or effort and the final management decision that accounts for uncertainty and risk). Risk equivalency can be achieved using management strategy evaluation to select the values for control variables, which determine the buffer given the uncertainty associated with the assessment. 相似文献
88.
Gisele J. dos Santos Jeana P. da Silva Alícia G. Hippólito Bárbara S. Ferro Elton Luís R. Oliveira Priscylla Tatiana C. G. Okamoto Maria Lucia G. Lourenço Vania Maria de Vasconcelos Machado Sheila C. Rahal Carlos R. Teixeira Alessandra Melchert 《Anatomia, histologia, embryologia》2020,49(2):299-306
This study aimed to assess radiographic and tomographic cardiac parameters, including width and length of the heart, and the ratio of heart width to coelom width of blue-fronted Amazon parrots (Amazona aestiva) with varying body condition scores. Thirty-five captive birds were included in the study and were allocated into one of three groups according to their respective body condition score: lean, ideal and obese. No differences were observed among the groups with regard to radiographic and tomographic measurements. Computed tomography enabled better identification of the structures of the cardiovascular system without interference from the overlying structures of the celomatic cavity observed in radiographic images. However, radiographic examinations should still be considered the standard screening method to identify cardiac alterations, such as increased or reduced organ dimensions. Standardizing the techniques and measurements performed in this study may serve as a basis for further research in the field. 相似文献
89.
Oliveira HM Segundo MA Lima JL Grassi V Zagatto EA 《Journal of agricultural and food chemistry》2006,54(12):4136-4140
A sequential injection system for the automatic determination of glycerol in wine and beer was developed. The method is based on the rate of formation of NADH from the reaction of glycerol and NAD+ catalyzed by the enzyme glycerol dehydrogenase in solution. The determination of glycerol was performed between 0.3 and 3.0 mmol L(-1) (0.028 and 0.276 g L(-1)), and good repeatability was attained (rsd < 3.6%, n = 5) for all samples tested. The determination rate was 54 h(-1), the reagent consumption was only 0.75 micromol of NAD+ and 5.4 ng of enzyme per assay, and the waste production was 2.12 mL per assay. Results obtained for samples were in agreement with those obtained with the batch enzymatic method. 相似文献
90.
da Silva Isadora Gonçalves Castoldi Renata de Oliveira Charlo Hamilton César de Souza Miranda Mateus Nunes Thaíssa Dias Cardoso Costa Luciene Lacerda Lemes Ernane Miranda 《Journal of Crop Science and Biotechnology》2020,23(2):191-196
Journal of Crop Science and Biotechnology - The cultivation of sweet corn is expanding in Brazil, but there are serious constraints about the availability of commercial cultivars. The selection of... 相似文献