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RESUMO.Com o aumento do número de criatórios e consequentemente, o incremento da procura e uso da água, os piscicultores podem ou até já estão se tornando alvos preferidos dos órgãos de controle ambiental, comprovadamente pela imposição de regras, leis e exigências, tanto no aspecto do uso do terreno, uso/reuso e despejo das águas, escolha, introdução e translocação de espécies exóticas ou nativas, quanto no aspecto sanitário do produto obtido. O desenvolvimento da atividade aquícola, juntamente com a tomada de consciência relativamente recente dos problemas ambientais, justifica plenamente a atenção que se deve oferecer ao item "qualidade da água", em especial àquela advinda de ação das criações intensivas e semiintensivas. Para a água utilizada na aquicultura, sugerese que os criadores devam estabelecer normas de conduta quanto a sua obtenção, uso e reuso a sua disposição e se preocupem em aplicar métodos de avaliação e recuperação simples e objetivos.Palavras chave: Aquicultura, piscicultura, qualidade da água Water quality and its use fish farms ABSTRACT. With the increase in the number of farms and consequently an increase in demand and use of water, fish farmers can or even are already becoming favorite targets of environmental organizations, proven by the imposition of rules, laws and requirements, both in the aspect of land use, use / reuse and disposal of water, choice, introduction and translocation of alien or native species, as the health aspects of the product. The development of aquaculture activity, along with the relatively recent awareness of environmental problems, fully justifies the attention it must offer the item "water quality", in particular to that arising from the action of intensive and semiintensivas creations. For water used in aquaculture, it is suggested that farmers should establish rules of conduct as their production, use and reuse your mood and worry in applying evaluation methods and simple recovery and objectives.Keywords: Aquaculture, fish farming, water quality Calidad del agua y su uso en pisciculturas RESUMEN. Con la ampliación del número de criaderos y consecuentemente, el aumento de la demanda y uso del agua, Los acuicultores pueden o hasta que ya se están volviendo albos preferidos de los órganos de control ambiental, comprobadamente por la imposición de reglas, leyes y exigencias, tanto desde el uso de la tierra, uso/reutilización e descarga de las aguas, selección, introducción e translocación de especies exóticas o nativas, cuanto al

The study was conducted in order to conduct a review of the importance of ecophysiology of forage plants, to address the impacts of biotic and abiotic factors on plants and their morphological and physiological responses. The physical stress caused by soil compaction affect the development of the root system, is this condition plant shown as response greater emission lateral roots as an alternative to explore larger volume of soil. The flooding condition affect forage species differently. In this environment, the most adapted plants present the formation of adventitious roots. In dry condition tolerant plants have the ability to deepen the root system, besides their anatomical and physiological modifications to survive. Grazing reduces the photosynthetic apparatus of plants and to recover from defoliation and maintain productive changes occur in the population of tillers and the relationship between source and sink of the remaining organs. In the shadow environment the most limitation is the low solar radiation. Forage under the influence of shadow prioritize assimilates partition to shoot at the expense of roots and also have anatomical and physiological adaptations in the leaf blade to intercept and absorb more light. The nutrient deficiency impairs the growth of the plant community, as an alternative the same stimulate the development of the root system in order to meet the demand for this resource. The plant adaptation to biotic and abiotic factors promote changes in its characteristics to ensure survival, but that does not necessarily imply maintaining production of the organs of interest. However, such changes must be known to respect the limits of use and ensure of forage production efficiency.

ABSTRACT. The study was carried out with the objective of verifying which measures and morphometric ratios are more directly related to the body yield of Nile tilapia, Oreochromis niloticus, in two weight classes. Data were analyzed from 257 specimens of tilapia divided into two weight classes: p1 = 400 to 599 g and p2 = 600 to 900 g. The morphometric measurements standard length (SL), head length (HL), body height (BH) and body width (BW), and the ratios of these measures (HL / SL, BH / SL, BW / SL, HL / BH, BW / BH, BW / HL) were evaluated. The following body yields were calculated: carcass (RCAR), fillet (RFILE) and head (RCAB). The data were initially submitted to the "stepwise" procedure to eliminate problems of multicollinearity among the morphometric variables, then the correlations between the dependent variables (body yield) and the independent variables (measured and morphometric relationships) were calculated. Later, these correlations were divided into direct and indirect effects through path analysis, and the direct and indirect contributions of each variable measured in percentage terms. The morphometric ratio BW/HL, for both weight classes, was the variable most highly correlated and with the highest direct effect on RFILE and RCAB, showing to be the most important morphometric variable studied for tilapia carcass trait determination.Keywords: path analysis, evaluation of carcass, animal breeding, morphometry, Oreochromis niloticus.Efeitos diretos e indiretos de medidas morfométricas e razões sobre o rendimento do corpo de tilápia do Nilo, Oreochromis niloticus RESUMO. O estudo foi realizado com o objetivo de verificar quais medidas e razões morfométricas estão mais diretamente relacionadas com os rendimentos corporais da tilápia do Nilo, Oreochromis niloticus, em duas classes de peso. Foram analisados os dados de 257 exemplares de tilápia divididos em duas categorias de peso: p1 = 400 a 599 g e p2 = 600 a 900 g. As medidas morfométricas comprimento padrão (CP), comprimento da cabeça (CC), altura do corpo (AC) e largura do corpo (LC), e as razões entre estas medidas (CC / CP, AC / CP, LC / CP, LC / CC, LC / AC, CC / AC) foram avaliadas. Os rendimentos corporais calculados foram: carcaça (RCAR), filé (RFILE) e cabeça (RCAB). Os dados foram inicialmente submetidos ao procedimento 'stepwise' para eliminar os problemas de multicolinearidade entre as variáveis morfométricas, em seguida, as correlações entre as variáveis dependentes (rendimentos corporais) e as variáveis independentes (medidas e razões morfométrica) foram calculados. Posteriormente estas correlações foram desdobradas em efeitos diretos e indiretos por meio de análise de trilha e as contribuições diretas e indiretas de cada variável foram quantificadas percentualmente. A razão morfométrica LC / CC, para ambas as classes de peso, foi a variável mais altamente correlacionada e com o maior efeito direto sobre RFILE e RCAB, mostrando ser a variável morfométrica estudada mais importante para determinação das características de carcaça da tilá...

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Traditional methods of typing Vibrio cholerae define virulent strains according to their recognition by sera directed against the known epidemic serogroups O1 and O139, overlooking potentially virulent non-O1/non-O139 strains. Here, we have undertaken the characterization of eight clinical isolates of non-O1/non-O139 V. cholerae, collected during cholera outbreaks in Brazil. Seven of these were typed as O26 and one, 17155, was defined as non-typable. A PCR-based approach has previously detected in these strains several virulence genes derived from the CTXvarphi prophage and generally associated with pathogenic strains. Here, the presence of the O1-specific wbeN gene was investigated through PCR and found to be restricted to strain 17155, as well as one of the O26 strains, 4756, although neither strain was recognized by O1-specific antisera. The same two isolates were the only strains able to express the cholera toxin in culture, assayed by western blotting. They also possessed four repeats of the heptanucleotide TTTTGAT upstream of the ctxAB genes encoding the cholera toxin. The remaining strains possessed only two intact repeats, whereas pathogenic O1 possessed four to six repeats. To define their evolutionary relationships, selected 16S-23S intergenic rRNA spacer regions were sequenced from the various strains and the resulting sequences used to build phylogenetic trees. Strains 4756 and 17155 always clustered with control O1 strains, whereas the remaining O26 strains clustered separately. These results confirm that, despite their serological phenotype, these two strains are genotypically related to O1 strains and potentially able to produce epidemic cholera.

Com o aumento da produção de tilápias em sistemas superintensivos, o número de casos de doenças bacterianas nesses peixes vem aumentando significativamente. O produtor acaba não encontrando meios de detecção e diagnósticos precisos para as doenças que acarretam na mortalidade de praticamente toda a produção. O uso indiscriminado de antibióticos e outras drogas têm selecionado espécies mais resistentes de microorganismos e o número de pesquisas sobre vacinas tem apresentado um crescimento significativo nos últimos anos, porém sem grandes sucessos.  O manejo e a seleção de espécies de peixes mais resistentes vêm sendo usada como uma boa forma de prevenção de doenças bacterianas. Esta revisão objetivou-se em descrever sobre as principais bactérias encontradas peixes de agua doce no Brasil, mostrando suas principais características e estudos realizados.

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