Digestibilidade do fósforo em fosfato em pó e microgranular em dietas para suínos / Digestibility of phosphorus in powder and microgranular phosphate in diets for pigs

Este estudo foi realizado com o objetivo de determinar as digestibilidades aparente e estandardizada de fosfatos para suínos em fase de crescimento, empregando duas metodologias. Foram usados 42 machos castrados, mestiços, com peso inicial de 37 ± 1,1kg em delineamento de blocos casualizados, em esquema fatorial 2 x 7, com dois métodos de coleta: coleta total de fezes e uso de indicador (cinza insolúvel em ácido [AIA ]) × sete tratamentos, que consistiram de uma dieta controle (CTR); três dietas contendo fosfato na forma de pó (PP): PPA = CTR + fosfato pó A, PPB = CTR + fosfato pó B, e PPC = CTR + fosfato pó C; e mais três dietas contendo o fosfato microgranular (MP): MP15 = CTR + fosfato microgranular 15%, MP45 = CTR + fosfato microgranular 45% e MP75 = CTR + fosfato microgranular 75%). Os valores de 15, 45, e 75% correspondem à solubilidade em água dos fosfatos. Foram seis repetições, e o animal foi considerado como unidade experimental. Os coeficientes de digestibilidade estandardizada dos fosfatos avaliadas pelo método de coleta total, em valores percentuais, foram: PPA = 86,9, PPB = 84,9, PPC = 81,9, MP15 = 89,4, MP45 = 88,8, e MP75 = 92,6. Os coeficientes de digestibilidade total estandardizada dos fosfatos avaliados pelo método do indicador, em valores percentuais foram: PPA = 75,9, PPB = 75,4, PPC = 75,6, MP15 = 84,9, MP45 = 78,0, e MP75 = 79,4. Considerando as duas metodologias avaliadas no presente trabalho, os fosfatos microgranulares constituem a melhor alternativa para a alimentação de suínos em fase de crescimento.(AU)

This study was realized with the objective to determine the apparent and standardized digestibilities of phosphates to pigs in growing phase, employing two methodologies. Forty-two crossbred barrows with an initial weight of 37 ± 1.1kg were used in a randomized-block design in a 2 × 7 factorial arrangement, with two collection methods: total fecal collection and the use of a indicator (acid insoluble ash [AIA]) × seven treatments, which consisted of a control diet (CTR); three diets containing phosphate in powder form (PP): PPA= CTR + powder phosphate A, PPB = CTR + powder phosphate B, and PPC= CTR + powder phosphate C; and another three diets containing the microgranular phosphate (MP): MP15 = CTR + microgranular phosphate 15%, MP45 = CTR + microgranular phosphate 45% and MP75 = CTR + microgranular phosphate 75%). The values of 15, 45, and 75% correspond to the water-solubility of the phosphates. There were six replicates, and the pig was considered as experimental unit. The standardized digestibility coefficients of the phosphates assessed by the total collection method, in percent values, were: PPA = 86.9, PPB = 84.9, PPC = 81.9, MP15 = 89.4, MP45 = 88.8, and MP75 = 92.6. The standardized-digestibility coefficients of the phosphates evaluated by the indicator method (AIA) in percent values were: PPA = 75.9, PPB = 75.4, PPC = 75.6, MP15 = 84.9, MP45 = 78.0, and MP75 = 79.4. Considering the two methodologies evaluated in the present work, the microgranular phosphates constitute the best alternative for feeding pigs in the growth phase.(AU)

Diets with phytase for broilers housed in environments with differenta air-conditioning systems / Dietas com fitase para frangos de corte alojados em ambientes com diferentes sistemas de climatização

The experiment was conducted to evaluate effect of different levels of phytase in broiler diets on performance variables, carcass yield and cuts, incorporation of crude protein, calcium and phosphorus in housing and levels of nitrogen, calcium and phosphorus in bed birds at 41 days of age. Six hundred and forty day-old chicks were distributed in boxes in a randomized design, factorial scheme 5 x 2, with five levels of phytase: 0, 1000, 2000, 3000 and 4000 FTU per kg diet, with four replications and 16 birds in experimental unit associated with two rooms (shed with ventilation and fogging and shed with ventilation without fogging). Birds were fed diets isonutrient maize and soybean meal, formulated to meet nutritional requirements, except for available phosphorus, which was reduced in 20% of requirement. The room with ventilation and fogging reduced skin temperature, improved feasibility and performance variables of broilers. It also increased incorporation of crude protein and phosphorus in poultry housing and elevated levels of nitrogen, calcium and phosphorus in bed, in relation to environment with only ventilation. Phytase supplementation to 4000 FTU per kg diet increased breast meat yield.(AU)

O experimento foi conduzido para avaliar o efeito de diferentes níveis de fitase nas dietas de frangos de corte sobre as variáveis de desempenho, rendimento de carcaça e cortes, incorporação de proteína bruta, cálcio e fósforo na carcaça e teores de nitrogênio, cálcio e fósforo na cama das aves aos 41 dias de idade. Seiscentos e quarenta pintos de um dia foram distribuídos em boxes em delineamento inteiramente casualizado, esquema fatorial 5 x 2, com cinco níveis de fitase: 0, 1000, 2000, 3000 e 4000 FTU por kg de ração, com quatro repetições e 16 aves na unidade experimental, associados a dois ambientes (galpão com ventilação e nebulização e galpão com ventilação sem nebulização). As aves receberam dietas isonutritivas à base de milho e farelo de soja, formuladas para atender as exigências nutricionais, exceto para fósforo disponível, que foi reduzido em 20% da exigência. O ambiente com ventilação e nebulização reduziu a temperatura média da pele, melhorou a viabilidade da criação e as variáveis de desempenho de frangos de corte. Além disso, aumentou a incorporação de proteína bruta e fósforo na carcaça das aves, bem como elevou os teores de nitrogênio, cálcio e fósforo na cama, em relação ao ambiente com apenas ventilação. A suplementação com fitase até 4000 FTU por kg da dieta aumentou o rendimento de peito.(AU)

Digestibilidade do fósforo em fosfato em pó e microgranular em dietas para suínos / Digestibility of phosphorus in powder and microgranular phosphate in diets for pigs

Este estudo foi realizado com o objetivo de determinar as digestibilidades aparente e estandardizada de fosfatos para suínos em fase de crescimento, empregando duas metodologias. Foram usados 42 machos castrados, mestiços, com peso inicial de 37 ± 1,1kg em delineamento de blocos casualizados, em esquema fatorial 2 x 7, com dois métodos de coleta: coleta total de fezes e uso de indicador (cinza insolúvel em ácido [AIA ]) × sete tratamentos, que consistiram de uma dieta controle (CTR); três dietas contendo fosfato na forma de pó (PP): PPA = CTR + fosfato pó A, PPB = CTR + fosfato pó B, e PPC = CTR + fosfato pó C; e mais três dietas contendo o fosfato microgranular (MP): MP15 = CTR + fosfato microgranular 15%, MP45 = CTR + fosfato microgranular 45% e MP75 = CTR + fosfato microgranular 75%). Os valores de 15, 45, e 75% correspondem à solubilidade em água dos fosfatos. Foram seis repetições, e o animal foi considerado como unidade experimental. Os coeficientes de digestibilidade estandardizada dos fosfatos avaliadas pelo método de coleta total, em valores percentuais, foram: PPA = 86,9, PPB = 84,9, PPC = 81,9, MP15 = 89,4, MP45 = 88,8, e MP75 = 92,6. Os coeficientes de digestibilidade total estandardizada dos fosfatos avaliados pelo método do indicador, em valores percentuais foram: PPA = 75,9, PPB = 75,4, PPC = 75,6, MP15 = 84,9, MP45 = 78,0, e MP75 = 79,4. Considerando as duas metodologias avaliadas no presente trabalho, os fosfatos microgranulares constituem a melhor alternativa para a alimentação de suínos em fase de crescimento.

This study was realized with the objective to determine the apparent and standardized digestibilities of phosphates to pigs in growing phase, employing two methodologies. Forty-two crossbred barrows with an initial weight of 37 ± 1.1kg were used in a randomized-block design in a 2 × 7 factorial arrangement, with two collection methods: total fecal collection and the use of a indicator (acid insoluble ash [AIA]) × seven treatments, which consisted of a control diet (CTR); three diets containing phosphate in powder form (PP): PPA= CTR + powder phosphate A, PPB = CTR + powder phosphate B, and PPC= CTR + powder phosphate C; and another three diets containing the microgranular phosphate (MP): MP15 = CTR + microgranular phosphate 15%, MP45 = CTR + microgranular phosphate 45% and MP75 = CTR + microgranular phosphate 75%). The values of 15, 45, and 75% correspond to the water-solubility of the phosphates. There were six replicates, and the pig was considered as experimental unit. The standardized digestibility coefficients of the phosphates assessed by the total collection method, in percent values, were: PPA = 86.9, PPB = 84.9, PPC = 81.9, MP15 = 89.4, MP45 = 88.8, and MP75 = 92.6. The standardized-digestibility coefficients of the phosphates evaluated by the indicator method (AIA) in percent values were: PPA = 75.9, PPB = 75.4, PPC = 75.6, MP15 = 84.9, MP45 = 78.0, and MP75 = 79.4. Considering the two methodologies evaluated in the present work, the microgranular phosphates constitute the best alternative for feeding pigs in the growth phase.

Initial pH of medium affects organic acids production but do not affect phosphate solubilization

The pH of the culture medium directly influences the growth of microorganisms and the chemical processes that they perform. The aim of this study was to assess the influence of the initial pH of the culture medium on the production of 11 low-molecular-weight organic acids and on the solubilization of calcium phosphate by bacteria in growth medium (NBRIP). The following strains isolated from cowpea nodules were studied: UFLA03-08 (Rhizobium tropici), UFLA03-09 (Acinetobacter sp.), UFLA03-10 (Paenibacillus kribbensis), UFLA03-106 (Paenibacillus kribbensis) and UFLA03-116 (Paenibacillus sp.). The strains UFLA03-08, UFLA03-09, UFLA03-10 and UFLA03-106 solubilized Ca3(PO4)2 in liquid medium regardless of the initial pH, although without a significant difference between the treatments. The production of organic acids by these strains was assessed for all of the initial pH values investigated, and differences between the treatments were observed. Strains UFLA03-09 and UFLA03-10 produced the same acids at different initial pH values in the culture medium. There was no correlation between phosphorus solubilized from Ca3(PO4)2 in NBRIP liquid medium and the concentration of total organic acids at the different initial pH values. Therefore, the initial pH of the culture medium influences the production of organic acids by the strains UFLA03-08, UFLA03-09, UFLA03-10 and UFLA03-106 but it does not affect calcium phosphate solubilization.(AU)

Bioavailability of pollutants in bacterial communities of Rodrigo de Freitas Lagoon, Rio de Janeiro, Brazil

Processes involving heavy metals and other contaminants continue to present unsolved environmental questions. To advance the understanding of geochemical processes that involve the bioavailability of contaminants, cores where collected in the Rodrigo de Freitas lagoon, and analyzed for bacterial activity and metal concentrations. Results would suggest an extremely reducing environment where organic substances seem to be the predominant agents responsible for this geochemical process. Analytical data showed sulphate reduction to be the main agent driving this process, since this kind of bacteria was found to be active in all of the samples analyzed. Esterase enzyme production did not signal the influence of heavy metals and hydrocarbon concentrations and heavy metals were found to be unavailable for biota. However, correlation between results for bacterial biomass and the potentially mobile percentage of the total Ni concentrations would suggest a negative impact.

Screening and optimization of low-cost medium for Pseudomonas putida Rs-198 culture using RSM

The plant growth-promoting rhizobacterial strain Pseudomonas putida Rs-198 was isolated from salinized soils from Xinjiang Province. We optimized the composition of the low-cost medium of P. putida Rs-198 based on its bacterial concentration, as well as its phosphate-dissolving and indole acetic acid (IAA)-producing capabilities using the response surface methodology (RSM), and a mathematical model was developed to show the effect of each medium component and its interactions on phosphate dissolution and IAA production. The model predicted a maximum phosphate concentration in medium containing 63.23 mg/L inorganic phosphate with 49.22 g/L corn flour, 14.63 g/L soybean meal, 2.03 g/L K2HPO4, 0.19 g/L MnSO4 and 5.00 g/L NaCl. The maximum IAA concentration (18.73 mg/L) was predicted in medium containing 52.41 g/L corn flour, 15.82 g/L soybean meal, 2.40 g/L K2HPO4, 0.17 g/L MnSO4 and 5.00 g/L NaCl. These predicted values were also verified through experiments, with a cell density of 10(13) cfu/mL, phosphate dissolution of 64.33 mg/L, and IAA concentration of 18.08 mg/L. The excellent correlation between predicted and measured values of each model justifies the validity of both the response models. The study aims to provide a basis for industrialized fermentation using P. putida Rs-198.

Tripolifosfato de sódio e hexametafosfato de sódio na prevenção do cálculo dentário em cães / Sodium tripolyphosphate and sodium hexametaphosphate in preventing dental calculus accumulation in dogs

Avaliou-se o efeito de dois fosfatos, tripolifosfato de sódio (TPF) e hexametafosfato de sódio (HMF), incorporados à ração seca sob diferentes formas, como cobertura do grânulo da ração e no interior da massa da ração, na prevenção do desenvolvimento de cálculo dentário em 25 cães. O delineamento experimental utilizado foi inteiramente ao acaso, com cinco tratamentos e cinco repetições. Os tratamentos experimentais foram: 1) ração seca; 2) ração seca com TPF incorporado na cobertura do grânulo da ração; 3) ração seca com TPF incorporado na massa da ração; 4) ração seca com HMF incorporado na cobertura do grânulo da ração; 5) ração seca com HMF incorporado na massa da ração. Os animais receberam as dietas por um período experimental de 90 dias e, após esse período, foram submetidos à avaliação da área de cálculo dentário formado. A inclusão do HMF na ração seca, tanto na cobertura dos grânulos como no interior da massa, e do TPF, como cobertura dos grânulos, reduziu o acúmulo de cálculo dentário em cães, comparada à dieta sem adição de fosfatos. O HMF foi o fosfato mais eficiente, ao reduzir o acúmulo de cálculo dentário em até 47 por cento. As formas de inclusão do HMF na ração não influenciaram o acúmulo de cálculo dentário. Houve redução do desenvolvimento de cálculo dentário pela incorporação do TPF como cobertura do grânulo da ração, comparada à inclusão deste fosfato no interior da massa da ração. Conclui-se que os fosfatos incorporados na ração seca reduzem o acúmulo de cálculo dentário em cães.(AU)

The effect of dry food treated with sodium tripolyphosphate (TPP) or sodium hexametaphosphate (HMP), as kibble coated or added into the interior of the kibble on the accumulation of dental calculus in 25 dogs was evaluated. The study used a completely randomized design with five treatments and five repetitions. The experimental treatments were: 1) dry food; 2) dry food coated with TPP; 3) dry food with TPP incorporated into the interior of the kibble; 4) dry food coated with HMP; 5) dry food with HMP incorporated into the interior of the kibble. The animals received the diets for a 90-day experimental period, and then, the teeth were clinically examined for the presence of calculus. The inclusion of HMP in the dry food, as kibble coated or added into the interior of the kibble, and the inclusion of TPP as kibble coated reduced the accumulation of dental calculus compared to the control group without anti-calculus agents. HMP was the most efficient phosphate, reducing the accumulation of dental calculus in 47 percent. The forms of HMP inclusion in the dry food exerted no significant effect upon calculus formation. However, there was a reduction of calculus accumulation when TPF was incorporated as coating of the kibble, compared to the inclusion of this phosphate into the interior of the kibble. It was concluded that phosphates incorporated in the dry food reduce the accumulation of dental calculus in dogs.(AU)