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The objective was to evaluate the effect of in ovo feeding with glycerol on post-hatch development in broiler chicks. A total of 408 fertile eggs were divided into six experimental groups consisting of five 0.9% saline solutions containing various concentrations of glycerol (12.5, 25.0, 37.5 and 50.0 nmol/ml), and a placebo group (inoculation with saline only) and a control group (without inoculation). Inoculations were performed at 17 days of incubation for the evaluation of hatchability, embryo mortality, body and viscera weights, intestinal epithelium morphometry, blood glucose and liver glycerol kinase activity of chicks at hatching. Inoculation of solutions containing glycerol did not influence body weight at hatching and relative weights of liver, pancreas, intestine and breast. There was a quadratic effect of glycerol levels on the weights of yolk residue and gizzard and on blood glucose, and an increasing linear effect on spleen and heart weights. Higher duodenum and ileum villous height and deeper jejunum and ileum crypts were obtained with 50.0 nmol/ml of glycerol. A linear increasing effect was also observed in liver glycerol kinase activity; however, lower blood glucose was observed with 37.5 and 50 nmol/ml of glycerol. It is therefore concluded that glycerol may be used at doses of 25 nmol/ml as a substrate in in ovo feeding of broiler chickens. However, further studies must be conducted not only to establish an optimal dose but also to evaluate the combination of this substrate with other nutrients used in the in ovo feeding.

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RESUMO O controle de fitonematóides é uma tarefa difícil. A alta infestação de nematoides no solo obriga os produtores a usarem doses mais elevadas de nematicidas, ou ainda, a aumentarem a freqüência das aplicações, geralmente no solo, ocasionando maior potencial de dano ao homem e ao ambiente. Além disso, nematicidas convencionais vêm sofrendo grandes restrições de uso em muitos países. Desse modo, a busca de novas medidas de controle de fitonematóides é uma prioridade da agricultura sustentável. Desta forma, objetivou-se estudar o efeito de óleos essenciais de Lippia Alba, na mortalidade de juvenis pré-parasitas do segundo estádio de Meloidogyne incognita. O ensaio foi montado em delineamento inteiramente casualizado, com 4 repetições, em esquema fatorial 3×4 (3 quimiotipos x 4 concentrações) empregando-se três diferentes quimiotipos de L. Alba (I, II, III) nas concentrações de 0, 100, 500 e 1000 ppm, coletados em diferentes horas do dia (7, 9, 13, 16 e 19h). Os dados coletados (% de mortalidade) foram submetidos à análise de variância e os valores médios comparados por meio do teste de Tukey. Foi possível concluir que Lippia alba contém, em seu óleo essencial, compostos com efeitos significativos na mortalidade de juvenis de segundo estádio (J2) de M. incognita. Dessa forma, é importante destacar que o acentuado efeito nematicida do óleo essencial de L. alba sugere a possibilidade de seu uso no controle de M. incognita.

ABSTRACT The control of nematodes is difficult. The high infestation of nematodes in the soil requires the producers use higher doses of nematicides, increasing the frequency of applications, usually in soil, causing negative effects to humans and the environment. Furthermore, conventional nematicides have suffered great use restrictions in many countries. Thus, the search for new measures to control nematodes is a priority of sustainable agriculture. Thus, the objective of this study was available the effect of essential oils from Lippia Alba against Meloidogyne incognita. The experiment was conducted in a completely randomized design with four replications in a factorial 3x4 (3 chemotypes and 4 concentrations) using three different chemotypes of L. Alba (I, II, III) at concentrations of 0, 100, 500 and 1000 ppm, collected in different times of day (7 AM, 9 AM, 1 PM, 4 PM e 7 PM). The data collected (% mortality) were subjected to analysis of variance and mean values were compared using the Tukey test. It was able to conclude that L. alba contains in its essential oil, compounds with significant effects on mortality of M. incognita. Thus, it is important to note that the greatest nematicide effect of essential oil of L. alba suggests the possibility of its use to control M. incognita.

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A adaptabilidade de caprinos de dois grupos genéticos, Saanen e Azul, às condições climáticas do Meio-Norte do Brasil foi avaliada por meio dos testes de Ibéria, Benezra e Rainsby. Nos dois primeiros, foram utilizadas sete fêmeas de cada grupo racial e, no terceiro, quatro fêmeas de cada grupo. Foram realizadas quatro coletas de dados em cada período (chuvoso e seco) de 2005. Foi utilizado delineamento inteiramente ao acaso, em fatorial 2x2 (duas raças e dois períodos). Os valores do coeficiente de tolerância ao calor do teste de Ibéria no período seco diferiram entre os grupos (P<0,05) (Saanen = 97,65 e Azul = 94,31). Houve diferença entre grupos (P<0,05) quanto ao coeficiente de adaptabilidade 1 do teste de Benezra, nos dois períodos (chuvoso: Saanen = 5,13 e Azul = 3,26; seco: Saanen = 5,86 e Azul = 2,87). No teste de Rainsby, no grupo Azul, houve o retorno à temperatura de repouso nos dois períodos. Na Saanen, no período no seco, 100 minutos não foram suficientes para o retorno à temperatura de repouso. O grupo racial Azul mostrou-se mais adaptado às condições do Meio-Norte.(AU)

This study was undertaken to evaluate Saanen and Azul goats' adaptability to the Brazilian Middle-North region, based on adaptation indexes (Iberia, Benezra and Rainsby tests). A totall of seven and four females, respectively, of each group were used in two tests and four collections were performed during the rainy and dry periods of 2005 year. A completely randomized experimental design in a 2 x 2 (2 groups x 2 period) factorial treatment combination was used. Significant difference between groups (Saanen = 97.65 and Azul = 94.31) was observed for heat-tolerance coefficient (Iberia) during the dry period (P<.05). Significant differences between groups (P<0.05) were also observed for adaptability, coefficient 1 (Benezra) for both rainy (Saanen = 5.13 and Azul = 3.26) and dry periods (Saanen = 5.86 and Azul = 2.87). Based on Rainsby test, Azul goats returned to rest temperature in both periods. During the dry period 100 minutes were not enough for Saanen goats return to rest temperature. Azul goats showed higher adaptability to environment conditions of the Brazilian Middle-North region.(AU)

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A adaptabilidade de caprinos de dois grupos genéticos, Saanen e Azul, às condições climáticas do Meio-Norte do Brasil foi avaliada por meio dos testes de Ibéria, Benezra e Rainsby. Nos dois primeiros, foram utilizadas sete fêmeas de cada grupo racial e, no terceiro, quatro fêmeas de cada grupo. Foram realizadas quatro coletas de dados em cada período (chuvoso e seco) de 2005. Foi utilizado delineamento inteiramente ao acaso, em fatorial 2x2 (duas raças e dois períodos). Os valores do coeficiente de tolerância ao calor do teste de Ibéria no período seco diferiram entre os grupos (P<0,05) (Saanen = 97,65 e Azul = 94,31). Houve diferença entre grupos (P<0,05) quanto ao coeficiente de adaptabilidade 1 do teste de Benezra, nos dois períodos (chuvoso: Saanen = 5,13 e Azul = 3,26; seco: Saanen = 5,86 e Azul = 2,87). No teste de Rainsby, no grupo Azul, houve o retorno à temperatura de repouso nos dois períodos. Na Saanen, no período no seco, 100 minutos não foram suficientes para o retorno à temperatura de repouso. O grupo racial Azul mostrou-se mais adaptado às condições do Meio-Norte.

This study was undertaken to evaluate Saanen and Azul goats' adaptability to the Brazilian Middle-North region, based on adaptation indexes (Iberia, Benezra and Rainsby tests). A totall of seven and four females, respectively, of each group were used in two tests and four collections were performed during the rainy and dry periods of 2005 year. A completely randomized experimental design in a 2 x 2 (2 groups x 2 period) factorial treatment combination was used. Significant difference between groups (Saanen = 97.65 and Azul = 94.31) was observed for heat-tolerance coefficient (Iberia) during the dry period (P<.05). Significant differences between groups (P<0.05) were also observed for adaptability, coefficient 1 (Benezra) for both rainy (Saanen = 5.13 and Azul = 3.26) and dry periods (Saanen = 5.86 and Azul = 2.87). Based on Rainsby test, Azul goats returned to rest temperature in both periods. During the dry period 100 minutes were not enough for Saanen goats return to rest temperature. Azul goats showed higher adaptability to environment conditions of the Brazilian Middle-North region.

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The need for prediction is widely recognized in limnology. In this study, data from 25 lakes of the Upper Paraná River floodplain were used to build models to predict chlorophyll-a and dissolved oxygen concentrations. Akaike's information criterion (AIC) was used as a criterion for model selection. Models were validated with independent data obtained in the same lakes in 2001. Predictor variables that significantly explained chlorophyll-a concentration were pH, electrical conductivity, total seston (positive correlation) and nitrate (negative correlation). This model explained 52% of chlorophyll variability. Variables that significantly explained dissolved oxygen concentration were pH, lake area and nitrate (all positive correlations); water temperature and electrical conductivity were negatively correlated with oxygen. This model explained 54% of oxygen variability. Validation with independent data showed that both models had the potential to predict algal biomass and dissolved oxygen concentration in these lakes. These findings suggest that multiple regression models are valuable and practical tools for understanding the dynamics of ecosystems and that predictive limnology may still be considered a powerful approach in aquatic ecology.

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The need for prediction is widely recognized in limnology. In this study, data from 25 lakes of the Upper Paraná River floodplain were used to build models to predict chlorophyll-a and dissolved oxygen concentrations. Akaike's information criterion (AIC) was used as a criterion for model selection. Models were validated with independent data obtained in the same lakes in 2001. Predictor variables that significantly explained chlorophyll-a concentration were pH, electrical conductivity, total seston (positive correlation) and nitrate (negative correlation). This model explained 52 percent of chlorophyll variability. Variables that significantly explained dissolved oxygen concentration were pH, lake area and nitrate (all positive correlations); water temperature and electrical conductivity were negatively correlated with oxygen. This model explained 54 percent of oxygen variability. Validation with independent data showed that both models had the potential to predict algal biomass and dissolved oxygen concentration in these lakes. These findings suggest that multiple regression models are valuable and practical tools for understanding the dynamics of ecosystems and that predictive limnology may still be considered a powerful approach in aquatic ecology.

O objetivo desse estudo foi o de construir modelos para predizer as concentrações de clorofila-a e oxigênio dissolvido em lagoas da planície de inundação do Alto Rio Paraná. Para tanto, foram selecionadas 25 lagoas na planície de inundação. O critério de Akaike (AIC) foi utilizado para a seleção dos modelos. Posteriormente, os modelos foram validados utilizando dados independentes obtidos nas mesmas lagoas. As variáveis que explicaram significativamente as concentrações de clorofila-a (52 por cento) foram pH, condutividade elétrica, material em suspensão (relação positiva) e nitrato (relação negativa). As variáveis que melhor explicaram as concentrações de oxigênio dissolvido (54 por cento) foram pH, área das lagoas, nitrato (relação positiva), temperatura da água e condutividade elétrica (relação negativa). A elevada capacidade preditiva desses modelos foi demonstrada através da utilização de dados independentes. Esses resultados demonstraram que a limnologia preditiva continua sendo uma importante área de pesquisa na ecologia aquática.

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Nitrification process performance was evaluated using a three-phase fluidized-bed bioreactor. A synthetic effluent was used for this experiment containing 180-230 mg/L of chemical oxygen demand (COD), 25-30 mg/L of N-NH4+, 12 to 13 mg/L of total phosphorous, and micronutrients. The bioreactor used for denitrification behaved as completely mixed. The results indicate that the nitrification process was efficient, reaching efficiencies of about 98%. The best results related to the efficiency of the denitrification process were obtained when the processes were supplemented with the carbon source. The results indicated an efficiency of 86-98% COD removal.

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Resultado de 129 punçöes da vilosidade coriônica para diagnóstico pré-natal no primeiro trimestre de gestaçäo. Os métodos de rotina par preparaçäo direta, preparaçäo de 24 horas e cultura de longa duraçäo, bem como as indicaçöes säo descritos detalhadamente. Tendo em vista a precocidade desse exame e alto sucesso de técnica (97,4%), pode-se concluir pela sua aceitabilidade como método complementar de diagnóstico genético pré-natal

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