Effects of ammonia on gill (Na+, K+)-ATPase kinetics in a hololimnetic population of the Amazon River shrimp Macrobrachium amazonicum.

Water quality is essential for successful aquaculture. For freshwater shrimp farming, ammonia concentrations can increase considerably, even when culture water is renewed frequently, consequently increasing the risk of ammonia intoxication. We investigated ammonia lethality (LC50-96 h) in a hololimnetic population of the Amazon River shrimp Macrobrachium amazonicum from the Paraná/Paraguay River basin, including the effects of exposure to 4.93 mg L-1 total ammonia concentration on gill (Na+, K+)-ATPase activity. The mean LC50-96 h was 49.27 mg L-1 total ammonia, corresponding to 1.8 mg L-1 un-ionized ammonia. Except for NH4+ affinity that increased 2.5-fold, that of the gill (Na+, K+)-ATPase for ATP, Mg2+, Na+, K+ and ouabain was unchanged after ammonia exposure. Western blotting of gill microsomal preparations from fresh caught shrimps showed a single immunoreactive band of ≈110 kDa, corresponding to the gill (Na+, K+)-ATPase α-subunit. Ammonia exposure increased (Na+, K+)-ATPase activity by ≈25%, coincident with an additional 130 kDa α-subunit immunoreactive band, and increased K+-stimulated and V(H+)-ATPase activities by ≈2.5-fold. Macrobrachium amazonicum from the Paraná/Paraguay River basin is as tolerant to ammonia as are other Amazon River basins populations, showing toxicity comparable to that of marine crustaceans.

A Heuristic and Data Mining Model for Predicting Broiler House Environment Suitability.

The proper combination of environment and flock-based variables plays a critical role in broiler production. However, the housing environment control is mainly focused on temperature monitoring during the broiler growth process. The present study developed a novel predictive model to predict the broiler (Gallus gallus domesticus) rearing conditions' suitability using a data-mining process centered on flock-based and environmental variables. Data were recorded inside four commercial controlled environment broiler houses. The data analysis was conducted in three steps. First, we performed an exploratory and descriptive analysis of the environmental data. In the second step, we labeled the target variable that led to a specific broiler-rearing scenario depending on the age of the birds, the environmental dry-bulb temperature and relative humidity, the ammonia concentration, and the ventilation rate. The output (final rearing condition) was discretized into four categories ('Excellent', 'Good', 'Moderate', and 'Inappropriate'). In the third step, we used the dataset to develop tree models using the data-mining process. The random-tree model only presented accuracy for predicting the 'Excellent' and 'Moderate' rearing conditions. The decision-tree model had high accuracy and indicated that broiler age, relative humidity, and ammonia concentration play a critical role in proper rearing conditions. Using a large amount of data allows the data-mining approach to building up 'if-then' rules that indicate suitable environmental control decision-making by broiler farmers.

Influência de subprodutos de oleaginosas sobre parâmetros ruminais e a degradação da matéria seca e da proteína bruta / Influence byproducts of oleaginous on ruminal parameters and degradation of dry matter and crude protein

Avaliou-se o efeito da adição de subprodutos de oleaginosas na dieta de ovinos em substituição ao farelo de soja. Foram distribuídos quatro ovinos Santa Inês, com peso corporal de, aproximadamente, 40kg, canulados no rúmen, em quadrado latino (4x4), com quatro dietas e quatro períodos, analisados por regressão para a avaliação da degradação ruminal, dos valores de pH e das concentrações de nitrogênio amoniacal in vivo. Os subprodutos foram as tortas de amendoim, girassol e soja, em dietas isonitrogenadas, com 70% de concentrado e 30% de volumoso (feno de tifton). Não foi observado efeito da interação tempo x dieta para os valores de pH e concentração ruminal de nitrogênio amoniacal (P>0,05). O pH apresentou valor médio de 6,2. As concentrações ruminais de nitrogênio amoniacal não foram afetadas, com valor médio de 29,9mg/dL. Não foram observadas diferenças (P>0,05) nas taxas de degradação da matéria seca e na degradabilidade potencial.

The aim of this work was to evaluate the introduction of oleaginous byproducts in sheep feeding as a replacement for soybean meal. Four sheep weighing 40kg, with cannulated rumen were selected in a Latin Square (4x4) design, with for diets and four periods analyzed by regression for ruminal degradability evaluate, pH values and ammonia nitrogen concentration in vivo. Byproducts were the following cakes: peanut, sunflower and soybean, in isonitrogenous diets with 70% concentrate and 30% roughage (tifton hay). There was no effect of diet x time interaction for pH and ruminal concentrations of ammonia nitrogen (P>0.05). The average pH value was 6.2. Ruminal concentrations of ammonia nitrogen were not affected, and had an average value of 29.9mg/dL. There were no differences (P>0.05) in DM degradation and degradability rates. The use of high degradability protein sources, such as soybean cake and peanut cake, proved to be an interesting alternative to replace soybean meal.

Influência de subprodutos de oleaginosas sobre parâmetros ruminais e a degradação da matéria seca e da proteína bruta / Influence byproducts of oleaginous on ruminal parameters and degradation of dry matter and crude protein

Avaliou-se o efeito da adição de subprodutos de oleaginosas na dieta de ovinos em substituição ao farelo de soja. Foram distribuídos quatro ovinos Santa Inês, com peso corporal de, aproximadamente, 40kg, canulados no rúmen, em quadrado latino (4x4), com quatro dietas e quatro períodos, analisados por regressão para a avaliação da degradação ruminal, dos valores de pH e das concentrações de nitrogênio amoniacal in vivo. Os subprodutos foram as tortas de amendoim, girassol e soja, em dietas isonitrogenadas, com 70% de concentrado e 30% de volumoso (feno de tifton). Não foi observado efeito da interação tempo x dieta para os valores de pH e concentração ruminal de nitrogênio amoniacal (P>0,05). O pH apresentou valor médio de 6,2. As concentrações ruminais de nitrogênio amoniacal não foram afetadas, com valor médio de 29,9mg/dL. Não foram observadas diferenças (P>0,05) nas taxas de degradação da matéria seca e na degradabilidade potencial.(AU)

The aim of this work was to evaluate the introduction of oleaginous byproducts in sheep feeding as a replacement for soybean meal. Four sheep weighing 40kg, with cannulated rumen were selected in a Latin Square (4x4) design, with for diets and four periods analyzed by regression for ruminal degradability evaluate, pH values and ammonia nitrogen concentration in vivo. Byproducts were the following cakes: peanut, sunflower and soybean, in isonitrogenous diets with 70% concentrate and 30% roughage (tifton hay). There was no effect of diet x time interaction for pH and ruminal concentrations of ammonia nitrogen (P>0.05). The average pH value was 6.2. Ruminal concentrations of ammonia nitrogen were not affected, and had an average value of 29.9mg/dL. There were no differences (P>0.05) in DM degradation and degradability rates. The use of high degradability protein sources, such as soybean cake and peanut cake, proved to be an interesting alternative to replace soybean meal.(AU)