Fibra, metabolismo ácido-básico e balanço de macroelementos em gatos
Carregando...
Data
2016-02-23
Autores
Loureiro, Bruna Agy [UNESP]
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
As fibras dietéticas são um grupo de carboidratos de interesse da nutrição de gatos. Estas são utilizadas em formulações específicas para gatos para reduzir a densidade energética de alimentos, previner e/ou auxilar o tratamento de doenças gastrintestinais e metabólicas e também para promover saúde intestinal devido ao estímulo de microorganismos produtores de ácidos graxos voláteis. Contudo, pouca informação existe a respeito das consequências metabólicas do consumo de fibras por gatos, seu efeito na excreção de água e eletrólitos, produção de urina ou mesmo o efeito da absorção de ácidos orgânicos derivados da fermentação microbiana intestinal. Este estudo verificou a influencia da fibra dietetica no balanço hidro-eletrolitico e de macroelementos, produção de oxalato e equilibrio ácido-basico de gatos. Foram utilizados 18 gatos adultos e três dietas: BP0, um dieta controle sem adição de fibra; PB8, com adição de 8% de polpa de beterrada e PB16, com adição de 16% de polpa de beterraba. Após 15 dias de adaptação, o consumo de alimento e água foram monitorados e as fezes e urina foram coletadas durante 8 dias. Neste período foram determinados o balanço hídrico dos animais, densidade, pH e volume de urina e coletadas amostras para determinação da concentração urinária de cálcio, fósforo, cloreto, sódio, potássio, magnésio, enxofre, ácido úrico, citrato e oxalato, para calculo da supersaturação relativa para oxalato de cálcio (SSR OxCa). Também foram determinados tempo de retenção da ingesta no trato digestório, produtos da fermentação nas fezes e excreção de bolas de pelo nas fezes. O equilíbrio ácido-básico dos animais em jejum e no pós-prandial foi acessado por hemogasometria do sangue venoso. Os resultados foram avaliados por meio de contrastes polinomiais (P<0,05). Em resposta a ingestão de fibra, os gatos apresentaram queda na digestibilidade dos nutrientes e aumento da excreção fecal de água (P<0,05), sem alterar a ingestão hídrica, com consequente redução da produção de urina (P<0,05). O pH urinário e a concentração de oxalato foram semelhantes entre tratamentos (P>0,05). O balanço de macroelementos foi influenciado pelo consumo de fibra, alterando a retenção de Ca, K, Mg e S (P<0,05). Estas alterações, no entanto, não se refletiram em aumento da SSR OxCa. Os gatos apresentaram aumento linear da excreção fecal de Na em resposta ao consumo de fibra e aumento na produção de ácidos graxos de cadeia curta e redução linear do pH das fezes (P<0,05). O tempo de retenção do alimento foi menor na dieta PB16 (P<0,05). A análise hemogasométrica dos gatos em jejum foi similar entre grupos, mas na avaliação pós-prandial foi verificada redução linear no pH sanguíneo, bicarbonato e excesso de bases sanguíneo após inclusão de fibra (P<0,05). Absorção de componentes fermentativos da degradação microbiana e a maior excreção fecal de Na e bicarbonato podem explicar as alterações no metabolismo intermediário dos gatos promovidas pela ingestão de fibra. A polpa de beterraba diminuiu o tempo de retenção da dieta no trato gastrointestinal, mas não alterou a excreção de bolas de pelo nas fezes.
Dietary fibers are a group of carbohydrate of interest to the nutrition of cats. These are used in specific formulations for cats to reduce food energy density, avoid or assist the treatment of gastrointestinal and metabolic diseases and also to promote intestinal health due to stimulus of microorganisms to produce volatile fatty acids. However, there is little information about the metabolic consequences of fiber intake for cats, their effect on water and electrolytes excretion, urine production, or even the effect of absorption of organic acids derived from intestinal microbial fermentation. The present study verified the influence of dietary fiber in water and macroelements balance, oxalate production and acid-base balance of cats. It were used 18 adult cats and three diets: BP0, a control diet without adding fiber; BP8 with 8% beet pulp added and BP16, with 16% beet pulp added. After 15 days of adaptation, food and water consumption were monitored, and feces and urine were collected 8 consecutive days. During this period were determined water balance of the animals, urine density, pH and volume and samples were collected to determine the urinary concentration of calcium, phosphorus, chloride, sodium, potassium, magnesium, sulfur, uric acid, citrate and oxalate, for calculation of relative supersaturation for calcium oxalate (RSS CaOx). Also were determined food retention time in the digestive tract, fecal fermentation end-products, hairball excretion and acid-base status of fasted animals and in post-prandial by blood gas analysis. The results were evaluated by polynomial contrasts (P <0.05). In response to fiber intake, cats presented decreased nutrient digestibility and increased fecal excretion of water (P <0.05) without altering water intake, with consequent reduction in urine production (P <0.05). The mineral balance was influenced by fiber consumption, altering Ca, K, Mg and S retention (P<0.05). These alterations did not reflected in increased RSS CaOx. Cats showed a linear increase in fecal excretion of Na in response to fiber consumption and increase in production of volatile fatty acids and linear reduction of fecal pH (p <0.05). The food retention time was lower in PB16 diet (P <0.05). The hemogasometric analysis in fasted cats was similar between groups, but postprandial evaluation was checked linear decrease in blood pH, bicarbonate and base excess blood after inclusion of fiber (P <0.05). Absorption of fermentation components of microbial degradation and increased fecal excretion of Na and bicarbonate can explain the changes in intermediary metabolism of cats promoted by fiber intake. Beet pulp decreases the retention time of the diet in the gastrointestinal tract, but did not affect the excretion of fecal hairballs.
Dietary fibers are a group of carbohydrate of interest to the nutrition of cats. These are used in specific formulations for cats to reduce food energy density, avoid or assist the treatment of gastrointestinal and metabolic diseases and also to promote intestinal health due to stimulus of microorganisms to produce volatile fatty acids. However, there is little information about the metabolic consequences of fiber intake for cats, their effect on water and electrolytes excretion, urine production, or even the effect of absorption of organic acids derived from intestinal microbial fermentation. The present study verified the influence of dietary fiber in water and macroelements balance, oxalate production and acid-base balance of cats. It were used 18 adult cats and three diets: BP0, a control diet without adding fiber; BP8 with 8% beet pulp added and BP16, with 16% beet pulp added. After 15 days of adaptation, food and water consumption were monitored, and feces and urine were collected 8 consecutive days. During this period were determined water balance of the animals, urine density, pH and volume and samples were collected to determine the urinary concentration of calcium, phosphorus, chloride, sodium, potassium, magnesium, sulfur, uric acid, citrate and oxalate, for calculation of relative supersaturation for calcium oxalate (RSS CaOx). Also were determined food retention time in the digestive tract, fecal fermentation end-products, hairball excretion and acid-base status of fasted animals and in post-prandial by blood gas analysis. The results were evaluated by polynomial contrasts (P <0.05). In response to fiber intake, cats presented decreased nutrient digestibility and increased fecal excretion of water (P <0.05) without altering water intake, with consequent reduction in urine production (P <0.05). The mineral balance was influenced by fiber consumption, altering Ca, K, Mg and S retention (P<0.05). These alterations did not reflected in increased RSS CaOx. Cats showed a linear increase in fecal excretion of Na in response to fiber consumption and increase in production of volatile fatty acids and linear reduction of fecal pH (p <0.05). The food retention time was lower in PB16 diet (P <0.05). The hemogasometric analysis in fasted cats was similar between groups, but postprandial evaluation was checked linear decrease in blood pH, bicarbonate and base excess blood after inclusion of fiber (P <0.05). Absorption of fermentation components of microbial degradation and increased fecal excretion of Na and bicarbonate can explain the changes in intermediary metabolism of cats promoted by fiber intake. Beet pulp decreases the retention time of the diet in the gastrointestinal tract, but did not affect the excretion of fecal hairballs.
Descrição
Palavras-chave
Água, Oxalato, Polpa de beterraba, Supersaturação relativa, Urina, Beet pulp, Water, Oxalate, Relative supersaturation, Urine