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451.
J M Reynes J L Soares C Keo S Ong N Y Heng B Vanhoye 《The Onderstepoort journal of veterinary research》1999,66(2):129-133
In order to provide relevant therapeutic answers to human patients exposed to risk of rabies infection who visit the Institut Pasteur du Cambodge for post-exposure treatment and to improve control of rabies in Cambodia, a pilot study was carried out in Phnom Penh Province in November and December 1997 with three objectives: characterization of the population of animals responsible for the exposure to rabies, observation of the animals concerned, and confirmation of the presence of rabies virus in the province. Between 18 November 1997 and 19 December 1997, 409 of the 741 patients treated at the Institut Pasteur du Cambodge because of an exposure to a known rabies vector were included in the study. The animals concerned were: 401 dogs (98%), six monkeys (1.5%) and two cats (0.5%). Three-hundred-and-seventy of the animals (90.5%) were owned, 4 (1%) were unowned but were available for characterization and observation, and 35 (8.6%) had an unknown ownership status and were not available for further study. The exposures occurred on private property in 84% of the cases, and 80 of the 370 owned animals (22%) lived in the same home as had the patient. The 374 animals with known ownership status were examined. Five were already dead and two of these five dogs had presented clinical signs typical of those of rabies. The male:female sex ratio of the dogs was 2.1:1. The 369 live animals were placed under observation for 10 d immediately after exposure of the humans had taken place. At the end of the period none of the animals had developed clinical signs of rabies, three had died of diseases other than rabies, and one was lost. Tests for the rabies nucleocapsid antigen were positive in two cases (the two suspected rabid dogs), confirming the presence of rabies in Phnom Penh Province. Consequently, we recommend measures to improve the control of rabies in Cambodia. 相似文献
452.
Curcuma longa supplementation in the diet of Astyanax aff. bimaculatus in preparation for transport 下载免费PDF全文
Pollyanna de Moraes França Ferreira Juliana Silva Rocha Juliana Rodrigues Gomes Débora Werneck Caldas Maria Tatiana Soares Martins Jerusa Maria de Oliveira Ana Lucia Salaro Jener Alexandre Sampaio Zuanon 《Aquaculture Research》2017,48(8):4524-4532
The physiological state of fish before transportation is an important aspect to be observed when reduction in losses due to mortality is aimed. Various preparative procedures for transport are reported, but little is known about the use of additives in fish diet. In this study, we aimed to evaluate the effect of dietary turmeric (Curcuma longa) supplementation on the tolerance of juvenile Astyanax aff. bimaculatus to transportation stress. The experimental design consisted of six treatments: 0, 20, 40, 60, 80 and 100.0 g kg?1 turmeric. Fish weighing 0.83 ± 0.04 g were distributed in 24 80‐L aquaria at a density of 0.5 fish L?1 and were fed to satiation three times a day for 60 days. After this period, fish were transported for 24 h in plastic bags (15 fish per bag). Using a discontinuous linear response plateau (LRP) model, the lowest estimated concentration of turmeric that maximized the survival rate was 16.67 g kg?1. Quadratic effects of turmeric on blood lactate levels were observed, and the estimated concentration of turmeric required to minimize blood lactate levels was 64.7 g kg?1. We observed quadratic effects of turmeric on superoxide dismutase activity and the concentration of malondialdehyde in fish gills and the turmeric concentrations required to minimize the transport stress effects on these variables were 42.50 and 83.33 g kg?1, respectively. Thus, dietary supplementation with turmeric enhanced the tolerance of juvenile A. aff. bimaculatus to transportation stress. 相似文献
453.
Pollyanna de Moraes França Ferreira Suellen Silva Condessa Juliana Silva Rocha Débora Werneck Caldas Juliana Rodrigues Gomes Maria Tatiana Soares Alex Junio Silva Cardoso Jener Alexandre Sampaio Zuanon 《Aquaculture Research》2017,48(9):4623-4631
With this study, we aimed to assess the safety of using Curcuma longa in fish feed. Juvenile Astyanax aff. bimaculatus (0.83 ± 0.04 g) were kept in 24 80‐L aquaria, at a density of 0.5 fish L?1 for 60 days. Six diets supplemented with 0.0, 20.0, 40.0, 60.0, 80.0 and 100.0 g kg?1 were evaluated. Histopathological analysis of the gills showed that there was an increasing linear effect of turmeric on the frequency of lamellar aneurysm, hypertrophy of mucous cells, oedema and necrosis. There was a quadratic effect of turmeric supplementation on the frequency of fusion and disruption of secondary lamellae, vacuolation and hypertrophy of the epithelial cells, and the estimated values to minimize these variables were 4.63, 25.93 and 24.46 g kg?1 respectively. There was a quadratic effect of turmeric on the gills index (IBRA), and the estimated value to minimize this index was 30.23 g kg?1. No effect of turmeric on the frequency of histopathological changes and organ index in fish liver was observed. Thus, we conclude that turmeric is not hepatotoxic for A. aff. bimaculatus; however, its use is safe at concentrations up to 30.23 g kg?1 diet as a function of its gill toxic effect at higher doses. 相似文献
454.
A method for collecting eggs of Pseudocapillaria tomentosa (Nematoda: Capillariidae) from zebrafish Danio rerio and efficacy of heat and chlorine for killing the nematode's eggs 下载免费PDF全文
Pseudocapillaria tomentosa is a common pathogen of zebrafish (Danio rerio) in research facilities. We developed a method to collect and concentrate the nematode eggs using a modified sugar centrifugation method and documented their normal development. Embryonating stages with blastomere formation followed by elongation of the embryo prior to larva formation cumulated in developed larvae inside the eggs and hatching after 5–10 day. We then evaluated the efficacy of heat and chlorine to kill them based on a larva development assay. Eggs were exposed to 40, 50, 60 °C for 30 min and 1 h. Chlorine treatment was performed at 100, 250, 500, 1000, 3000 and 6000 ppm for 10 min. Samples exposed to 40 °C for 30 min or 1 h showed incidences of larvated eggs similar to controls. In contrast, no larvation occurred with eggs exposed to either 50 or 60 °C for 30 min or 1 h. Remarkably, in repeated assays, samples exposed to low doses of chlorine (100, 250, 500 and 1000 ppm for 10 min) showed significantly higher incidence of larvation than controls. Eggs treated with 3000 ppm for 10 min did not develop larvae, and no eggs were found after 6000 ppm treatment. 相似文献
455.
Physiological responses of reared sea bream (Sparus aurata Linnaeus, 1758) to an Amyloodinium ocellatum outbreak 下载免费PDF全文
M Moreira D Schrama F Soares T Wulff P Pousão‐Ferreira P Rodrigues 《Journal of fish diseases》2017,40(11):1545-1560
Amyloodiniosis represents a major bottleneck for semi‐intensive aquaculture production in Southern Europe, causing extremely high mortalities. Amyloodinium ocellatum is a parasitic dinoflagellate that can infest almost all fish, crustacean and bivalves that live within its ecological range. Fish mortalities are usually attributed to anoxia, associated with serious gill hyperplasia, inflammation, haemorrhage and necrosis in heavy infestations; or with osmoregulatory impairment and secondary microbial infections due to severe epithelial damage in mild infestation. However, physiological information about the host responses to A. ocellatum infestation is scarce. In this work, we analysed the proteome of gilthead sea bream (Sparus aurata) plasma and relate it with haematological and immunological indicators, in order to enlighten the different physiological responses when exposed to an A. ocellatum outbreak. Using 2D‐DIGE, immunological and haematological analysis and in response to the A. ocellatum contamination we have identified several proteins associated with acute‐phase response, inflammation, lipid transport, homoeostasis, and osmoregulation, wound healing, neoplasia and iron transport. Overall, this preliminary study revealed that amyloodiniosis affects some fish functional pathways as revealed by the changes in the plasma proteome of S. aurata, and that the innate immunological system is not activated in the presence of the parasite. 相似文献
456.
Pollyanna de Moraes França Ferreira Maria Tatiana Soares Martins Débora Werneck Caldas Juliana Rodrigues Gomes Jerusa Maria de Oliveira Ana Lucia Salaro Juliana Silva Rocha Jener Alexandre Sampaio Zuanon 《Fish physiology and biochemistry》2017,43(3):691-702
The aim of the present study was to evaluate the effect of turmeric (Curcuma longa) as additive in the diet for Astyanax aff. bimaculatus. Fish (0.83 ± 0.04 g) were fed, for 60 days, with six diets containing 0.0, 20.0, 40.0, 60.0, 80.0, and 100.0 g turmeric kg?1 feed. There was an increasing linear effect of turmeric on the thickness of the muscular layer, and height and width of the folds of the intestine. In the liver, a quadratic effect was observed of turmeric on the percentage of hepatocyte cytoplasm and a decreasing linear effect on the percentage of sinusoid capillaries. A quadratic effect was also observed of turmeric on the liver glycogen. There was no effect of turmeric on the antioxidant activity in the liver, carcass composition or productive performance of the fish. Thus, we concluded that Curcuma longa has trophic effects on the epithelium and the muscular layer of the intestine of A. aff. bimaculatus. Additionally, low levels of Curcuma longa cause increased deposition of liver glycogen and high levels cause reduction. 相似文献
457.
Francisco Gerson Araújo Mrcia Cristina Costa de Azevedo Gustavo Henrique Soares Guedes Wagner Uehara 《Ecology of Freshwater Fish》2022,31(1):45-59
Increases in temperatures over the last century, more intensively after the eighties, were recorded in several databases for the south-eastern Brazil. These increases are likely to change fish communities in aquatic systems by decreasing abundances, biomass and sizes of some species more sensitive to climate change. Reservoirs may be particularly susceptible to the effects of climate change, as they isolate previously connected areas limiting fish dispersal and migration, as well as increasing water temperature and thermal stratification. We assessed temporal changes in the abundance and biomass of the ichthyofauna in an isolate reservoir (inflowing waters from small tributaries in a highland region) aiming to associate changes with climate effects over three decades (1990, 2000, 2010). Two abundant native species, a loricariid Loricariichthys castaneus (Castelnau, 1855) and a cichlid Geophagus brasiliensis (Quoy & Gaimard, 1824), were selected to assess eventual response to climate changes in their geographical distribution in the Southeast Atlantic Hydrographic Region, considering different carbon emission scenarios using ecological niche models. A decrease in the densities and biomass of the ichthyofauna and of the two selected species were observed in both summer and winter over the three decades, coinciding with increases in temperatures. These decreases were correlated with increases in positive anomalies of temperature, which may be an indicator of climatic changes, although with low explanation of the data variation. The mean size of L. castaneus decreased between the nineties and 2010, whereas no significant trend was found for the size of G. brasiliensis. Our predictions of new area for future adequacy indicated a loss in the distribution area for both species (mainly for G. brasiliensis), considering the most pessimistic scenario for 2050 and 2070, possibly due to climatic changes. Both hydroelectric dams and global warming pose threats to freshwater fish diversity, and both will interact. Changes observed in the fish assemblage over the last decades were essential for an assessment of the consequences of global warming in this type of reservoir combining larger scale studies with future projections. 相似文献
458.
Sebastião Soares de Oliveira Neto Francisca Franciana Sousa Pereira Tiago Zoz Carlos Eduardo da Silva Oliveira Vânia Moda Cirino 《Journal of Agronomy and Crop Science》2023,209(1):83-93
Brazil is the world's largest producer of common beans (Phaseolus vulgaris L.). Drought stress harms the morphological and agronomic traits of beans. This study evaluates the reaction to water deficit in five genotypes of black beans. The experiment was conducted in the IDR-IAPAR-EMATER in Londrina-PR, Brazil. A split-plot design was used, with three replications. The genotypes were included in the subplots and the treatments with or without water deficit in the plots. Water deficit was induced on the pre-flowering stage and maintained for 20 days in the plots submitted to drought stress. For the growth analysis, plants were collected at 35, 54 and 70 days after emergence. At the stage of physiological ripeness, several morphological and yield traits were evaluated. The genotypes IPR Uirapuru and BRS Esplendor can be considered tolerant and used as a tolerant source to water deficit in common bean germplasm banks. The line LP 08-90 has morphological and agronomic adaptations efficient to overcome water deficit's effects, presenting a higher grain yield in both crop conditions, which indicates the success of black beans breeding to deal with water deficit. 相似文献