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21.
Michael Goulding Eduardo Venticinque Mauro L. de B. Ribeiro Ronaldo B. Barthem Rosseval G. Leite Bruce Forsberg Paulo Petry Urbano Lopes da Silva‐Júnior Polliana Santos Ferraz Carlos Caas 《Fish and Fisheries》2019,20(1):138-158
Infrastructure development and overfishing in the Amazon make it imperative to define adequate scales for the ecosystem‐based management of commercial fisheries and the wetlands on which they depend. We mapped fisheries and fish ecology data from Brazil, Peru, Bolivia and Colombia to an explicit GIS framework of river basins and mainstems. Migratory species account for more than 80% of the known maximum catches of commercial fisheries across the Amazon. Of these migratory species, we nominated six long‐distance migratory fish taxa as flagship species to define the two main commercial fishery regions. The migrations of at least one goliath catfish species define a large‐scale longitudinal link joining the Andes, Amazon Lowlands and Amazon River estuary. Migratory Characiforms demonstrate interbasin wetland connectivity between nutrient‐rich and nutrient‐poor rivers over at least 2 million km2, or about one‐third of the Amazon Basin. We show that flooded forest area is the most important wetland variable explaining regional variations in migratory characiforme biomass as indicated by maximum annual fishery catches. The sustainable management of Amazon fisheries will require transnational cooperation and a paradigm shift from local community management alone to a more integrated approach that considers both rural and urban consumers and challenges, and the realistic life histories of migratory species. 相似文献
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M. A. Cardoso R. F. Cardoso R. D. C. Hirata M. H. Hirata C. Q. F. Leite A. C. B. Santos V. L. D. Siqueira W. Okano N. S. Rocha M. V. C. Lonardoni 《Zoonoses and public health》2009,56(8):465-470
Thirty‐five lymph node samples were taken from animals with macroscopic lesions consistent with Mycobacterium bovis infection. The animals were identified by postmortem examination in an abattoir in the northwestern region of state of Paraná, Brazil. Twenty‐two of the animals had previously been found to be tuberculin skin test positive. Tissue samples were decontaminated by Petroff’s method and processed for acid‐fast bacilli staining, culture in Stonebrink and Lowenstein‐Jensen media and DNA extraction. Lymph node DNA samples were amplified by PCR in the absence and presence (inhibitor controls) of DNA extracted from M. bovis culture. Mycobacterium bovis was identified in 14 (42.4%) lymph node samples by both PCR and by culture. The frequency of PCR‐positive results (54.5%) was similar to that of culture‐positive results (51.5%, P > 0.05). The percentage of PCR‐positive lymph nodes increased from 39.4% (13/33) to 54.5% (18/33) when samples that were initially PCR‐negative were reanalysed using 2.5 μl DNA (two samples) and 1 : 2 diluted DNA (three samples). PCR sensitivity was affected by inhibitors and by the amount of DNA in the clinical samples. Our results indicate that direct detection of M. bovis in lymph nodes by PCR may be a fast and useful tool for bovine tuberculosis epidemic management in the region. 相似文献
25.
Fabieli Pelissari Anderson Cleiton José Marco Aurélio Leite Fontes Antônio César Batista Matos Wilson Vicente Souza Pereira José Marcio Rocha Faria 《New Forests》2018,49(1):143-158
Knowledge of seed desiccation tolerance is fundamental for conservation and use of forest species. The protocol used for classification of seed desiccation tolerance and storage is time consuming and many times limited by the lack of information about optimum conditions for seed germination and treatments to overcome seed dormancy. This study evaluated 66 Brazilian tree species aiming to correlate seed characteristics with desiccation tolerance. For this purpose, a model was established to explain the relationship of tegument/seed mass ratio (SCR), seed mass, and water content of embryo + endosperm with desiccation tolerance. The principal component analysis showed the establishment of two groups, indicating the interaction between desiccation tolerance and seed characteristics. Recalcitrant seeds are more often associated with the water content of embryo + endosperm and water content of tegument + endocarp, while orthodox seeds are more associated with SCR and number of seeds per kilogram. The classification found using the model proposed was significantly correlated with desiccation tolerance and storage, with 92% confidence for the analyzed species. Seeds morphological characteristics can be used for prediction of desiccation tolerance and storage behavior; however, the use of a model that combines more variables increases the chance of accurate classification. 相似文献
26.
Janaina Kelli Gomes Arandas Ângelo Giuseppe Chaves Alves Olivardo Facó Ernandes Barboza Belchior Luciana Shiotsuki Paulo Márcio Barbosa de Arruda Leite Maria Norma Ribeiro 《Tropical animal health and production》2017,49(7):1479-1487
The implementation of sustainable breeding programs requires genetic breeding strategies that are appropriate for the reality production systems. It is also essential that the choice of animal selection criteria be based on breeders’ knowledge and objectives. This work is an ethno-zootechnical study of the Morada Nova sheep breed and its crossbreeds. The goals of this study were to register and analyze indigenous breeders’ knowledge and practices regarding animal selection criteria and to generate technical information to support a participatory breeding program of the breed. This study was conducted in the Morada Nova municipality in the state of Ceará, Brazil. Semi-structured interviews were evaluated using two groups of individuals, purebred Morada Nova sheep breeders (RMN, n = 13) and breeders of Morada Nova crossbreeds (MMN, n = 48). Interview questions were used to identify local selection criteria adopted by each group in the choice of animals for breeding. Data from the interviews were submitted to frequency distribution analysis and the Shapiro-Wilk test to verify their distribution. Later, the Kruskal-Wallis test was used to compare the two groups of farmers based on that information, in addition to multivariate statistical analysis and evaluation of Smith salience index. Breeders in the RMN group used selection criteria related to breed standards, such as pelage color. In contrast, breeders of the MMN group used criteria related to productivity, such as body conformation and milk production. Breeders should be engaged in the development of breeding programs, and it is important to consider their preferences and objectives when evaluating breeding animals. 相似文献
27.
Beatriz King-Díaz Flávio José Leite dos Santos Dalton Luiz Ferreira-Alves Blas Lotina-Hennsen 《Pesticide biochemistry and physiology》2010,96(3):119-126
6α,7β-Dihydroxyvouacapan-17β-oic acid (1) and methyl 6α,7β-dihydroxyvouacapan-17β-oate (8) were isolated from Pterodon polygalaeflorus Benth. 1 was modified to obtain 6α-hydroxyvouacapan-7-β,17β lactone (2). Then, 6-oxovouacapan-7β,17β lactone (3) was obtained from 2. The furanoditerpene ester derivatives: propyl 7β-hydroxy-6-oxovouacapan-17β-oate (4), butyl 7β-hydroxy-6-oxovouacapan-17β-oate (5), 2-methoxyethyl 7β-hydroxy-6-oxovouacapan-17β-oate (6) and 3-methylbut-2-enyl 7β-hydroxy-6-oxovouacapan-17β-oate (7) were synthesized from (3) and methyl 6α,7β-thiocarbonyldioxyvouacapan-17β-oate (9) was obtained from (8). In this work, the lactone ester derivatives 4-7 and 9 were tested on photosynthetic activities in an attempt to search for new compounds as potential herbicide agents that affect photosynthesis. All compounds inhibited ATP synthesis and electron flow from water to MV, therefore, they act as Hill reaction inhibitors, being 4- to 9-fold more potent than 2 and 3 as inhibitors of ATP synthesis. Their interaction site was located at PSII in a similar way to diuron. Furthermore, furanoditerpene esters 6 and 7 act as uncouplers, and were corroborated by enhancement of the light-activated Mg2+-ATPase, while 5 act as an energy transfer inhibitor. Finally 5-7 behave as herbicides, since they inhibit the biomass production of weeds assay. 相似文献
28.
Gustavo Henrique Batista Lara Clarice Queico Fujimura Leite Alessandro Guazzelli Adolfo Carlos Barreto Santos 《Research in veterinary science》2011,90(2):185-188
Mycobacterium spp. and other pathogens were investigated in 258 swine lymph nodes (129 with and 129 without apparent lesions), and 120 lymph nodes (60 with and 60 without lesions) from wild boars (Sus scrofa). A total of lymph nodes from swine and wild boars were collected of different animals. Submaxillar and mesenteric lymph nodes were submitted to microbiological examination and colonies suggestive of Mycobacterium spp. (alcohol-acid bacilli) were submitted to PCR Restriction Assay (PRA). In swine with lymphadenitis, Mycobacterium spp. (24.1%) and Rhodococcus equi (13.2%) were the most prevalent microorganisms, while in lymph nodes without lesions were identified a complex of microorganisms, including of environmental mycobacteria. In wild boars with lymphadenitis, ß-haemolytic Streptococcus (10.0%), Mycobacterium spp (8.4%) and R. equi (6.6%) were the most frequent. Among mycobacterias were identified predominantly Mycobacterium avium subspecies type 1 (48.3%) and M. avium subspecies type 2 (16.1%), followed by Mycobacterium intracellulare, Mycobacterium szulgai,Mycobacterium fortuitum, Mycobacterium gordonae, Mycobacterium simiae, Mycobacterium nonchromogenicum and Mycobacterium intracellulare type 2. 相似文献
29.
Development of an indirect ELISA-NcSRS2 for detection of Neospora caninum antibodies in cattle 总被引:1,自引:0,他引:1
Borsuk S Andreotti R Leite FP Pinto Lda S Simionatto S Hartleben CP Goetze M Oshiro LM Matos Mde F Berne ME 《Veterinary parasitology》2011,177(1-2):33-38
Neosporosis is of alarming economic concern in the cattle industry. The effectiveness of diagnostic tests for detecting specific antibodies against Neospora caninum is hampered by potential cross-reaction with other coccidia. Use of a single specific antigen might improve test specificity. An indirect enzyme-linked immunosorbent assay (ELISA) was developed using the truncated protein NcSRS2 expressed in Escherichia coli. The ELISA results were compared with those of the indirect fluorescence antibody test (IFAT). Receiver Operating Characteristic (ROC) and Tests in the Absence of a Gold Standard (TAGS) analysis revealed an assay having 96% specificity and 95% sensitivity when applied to 145 positive and 352 negative sera from two distinct cattle populations. Using OD ≤ 0.095 as the cut-off point, the assay's negative and positive predictive values ranged from 98.8% to 50.8% and from 58.8% to 99.1%, respectively, depending on neosporosis prevalence in a given area. The novel ELISA-NcSRS2 format described in the present report constitutes a specific and sensitive method for detecting N. caninum in cattle. 相似文献
30.
Lais S. B. Dias Dayane de S. Silva Gleidson Giordano P. de Carvalho Maria Leonor G. M. L. de Araújo Fabiano F. da Silva Mara Lúcia A. Pereira Jefferson R. Gandra Victor G. O. Lima Antnio C. S. dos Santos Lucas F. de A. Bulco Vagner M. Leite Jos Esler de Freitas Júnior 《Animal Science Journal》2020,91(1)
This study aimed to investigate the effects of chitosan and whole raw soybean on nutrient intake, apparent digestibility, nitrogen utilization, microbial protein synthesis, blood metabolites, feeding behavior, ruminal fermentation, digesta kinetics, and reticular flow of nutrients of buffaloes. Four ruminally‐cannulated Murrah buffaloes (351 ± 15 kg of initial BW) were randomly assigned according to a 4 × 4 Latin square design. Treatments were arranged as 2 × 2 factorial arrangement: the first factor was whole raw soybean (WRS), and the second factor was chitosan (CHI) with or without their inclusion in diets. Intake and apparent digestibility of ether extract (p < .01; p = .04, respectively), non‐fiber carbohydrates intake (p = .03) and apparent ruminal digestibility of dry matter (p = .01) were affected by diets. An interaction effect or tendency was observed for microbial nitrogen (p = .09), concentrations, ruminal ammonia nitrogen (p = .05), total volatile fatty acid (p = .03). Association of chitosan with whole raw soybean has potential effects as a modulator of rumen fermentation; therefore, chitosan can be applied as an alternative non‐ionophore for Murrah buffaloes. 相似文献