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Feed additives, such as prebiotics and essential oils, are used in pet foods and can affect digestibility, palatability, and intestinal functionality of dogs. The combined effects of yeast cell wall and oregano essential oil on apparent total tract digestibility (ATTD) and palatability of diet, intestinal fermentation products, and fecal microbiota in dogs were analyzed. Eighteen adult dogs were fed for 20 days with three dry extruded diets for adult dogs: control (without the additive), a diet containing 1.5 kg/ton of yeast cell wall and oregano essential oil (1.5YCO), and a diet containing 3.0 kg/ton of yeast cell wall and oregano essential oil (3.0YCO). The inclusion of both levels of YCO reduced the intake ratio. The addition of 3.0YCO reduced the ATTD of dry matter, compared to the control group (p < 0.05). There were greater putrescine and cadaverine concentrations and lower histamine and ammonia (p < 0.05) in the feces of dogs fed 3.0YCO. In addition, fecal odor of dogs fed YCO was less fetid than the control group (p < 0.05). There was greater fecal bacterial diversity in dogs fed with both dietary concentrations of YCO evaluated (p < 0.05). Dogs fed 1.5YCO and 3.0YCO showed higher relative abundance of Blautia and Faecalibacterium and lower abundance of Streptococcus (p < 0.05) in the feces, in comparison to the control group. Given the modulation of microorganisms considered beneficial and the lower fecal concentrations of histamine, phenols, and ammonia, the YCO blend resulted in indicators of improvement of intestinal functionality in dogs.
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This study aimed at evaluating the coefficients of total tract apparent digestibility (CTTAD) of nutrients, metabolisable energy (ME), diet palatability, faecal fermentative products and microbiota of dogs fed yeasts from different fermentation media and its fractions. Four diets were evaluated: control, without yeast (CO); diet with 10 g/kg brewer's yeast (BY); diet with 10 g/kg brewer's yeast + corn yeast (BCY); and diet with 10 g/kg BCY + cell wall fractions (BCYF). Twelve adult dogs were distributed in a randomized block design (periods). Each of the four diets was fed to a group of three dogs per period of 20 days, totalling two periods and six repetitions per treatment. Sixteen adult dogs were used for the palatability test, which compared the CO diet versus each one of the yeast diets. Data with normal distribution were subjected to analysis of variance (p < 0.05). Means were compared by orthogonal contrasts (p < 0.05): (A) CO diet versus BY, BCY and BCYF diets; (B) BY diet versus BCY and BCYF diets; (C) BCY diet versus BCYF diet. There was no difference in the CTTAD and ME of the diets (p > 0.05). Yeast diets reduced faecal odour and indole peak area (p < 0.05). Faecal short-chain fatty acids concentration was greater in dogs fed yeast diets compared to those fed the CO (p < 0.05). Yeast diets showed a higher intake ratio compared to the CO (p < 0.05). The BCY and BCYF diets resulted in a greater abundance of Bacteroides, Faecalibacterium, Coprococcus, and Phascolarctobacterium in relation to the CO (p < 0.05). Our results suggest that dietary yeast supplementation results in beneficial changes in intestinal functionality indicators, mainly with the combination of yeasts from brewers and corn fermentation media. In addition, yeast supplementation improves diet palatability without compromising nutrient digestibility.
Asunto(s)
Microbiota , Saccharomyces cerevisiae , Animales , Perros , Alimentación Animal/análisis , Dieta/veterinaria , Suplementos Dietéticos/análisis , Digestión , Heces/microbiología , FermentaciónRESUMEN
This study aimed to evaluate the effects of high-protein dried distillers grains (HPDDG) on palatability and metabolizable energy (ME) of the diet, apparent total tract digestibility (ATTD) of nutrients and energy, intestinal fermentation products, and fecal microbiota in dogs. Four diets containing 0, 70, 140, and 210 g/kg of HPDDG were manufactured. To evaluate the ME and the ATTD of macronutrients of HPDDG itself, an additional test diet was manufactured containing 70% of the control diet formula (0 g/kg) and 300 g/kg of HPDDG. Fifteen adult Beagle dogs were distributed in a randomized block design, with two periods of 15 d each (n = 6). The HPDDG digestibility was obtained using the Matterson substitution method. For the palatability test, 16 adult dogs were used, comparing the diets: 0 vs. 70 g/kg of HPDDG and 0 vs. 210 g/kg of HPDDG. The ATTD of HPDDG were: dry matter = 85.5%, crude protein = 91.2%, and acid-hydrolyzed ether extract = 84.6% and the ME content was 5,041.8 kcal/kg. The ATTD of macronutrients and ME of the diets and the fecal dry matter, score, pH, and ammonia of the dogs did not differ among treatments (P > 0.05). There was a linear increase in the fecal concentrations of valeric acid with the inclusion of HPDDG in the diet (P < 0.05). Streptococcus and Megamonas genera reduced linearly (P < 0.05), and Blautia, Lachnospira, Clostridiales, and Prevotella genera showed a quadratic response to the inclusion of HPDDG in the diet (P < 0.05). Alpha-diversity results showed an increase (P < 0.05) in the number of operational taxonomic units and Shannon index and a trend (P = 0.065) for a linear increase in the Chao-1 index with the dietary inclusion of HPDDG. Dogs preferred the 210 g/kg diet over the 0 g/kg HPDDG diet (P < 0.05). These results demonstrate that the HPDDG evaluated does not affect the utilization of nutrients in the diet, but it may modulate the fecal microbiome of dogs. In addition, HPDDG may contribute to diet palatability for dogs.
Considering the constant search for novel ingredients in animal nutrition and the increasing use of corn to produce ethanol, dried distillers grains with (DDGS) or without (DDG) solubles can potentially be used in dog food. Previous studies show that DDGS and DDG can contribute mainly with protein and fiber to the diets and that their fibrous fraction can potentially be fermented by the gut microbiota. However, DDGS and DDG may present variable digestibility in dogs. Besides, we did not find studies evaluating the nutritional effects of high-protein DDG (HPDDG) in dogs. This study evaluated the effects of HPDDG on diet digestibility and palatability and on variables related to the intestinal functionality of adult dogs. Our results demonstrated that HPDDG can be used in extruded diets for dogs due to its high digestibility and palatability. Besides, the HPDDG evaluated may result in a modulation of the gut microbiota, favoring bacteria considered beneficial for gut health.
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Dieta , Digestión , Perros , Animales , Fermentación , Heces , Dieta/veterinaria , Nutrientes , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Zea mays/químicaRESUMEN
The aim was to evaluate the effects of yeast probiotic on diet digestibility, fermentative metabolites, and fecal microbiota of dogs submitted to dietary change. Sixteen dogs were divided into two groups of eight dogs each: control, without, and with probiotic, receiving 0.12 g/dog/day of live Saccharomyces cerevisiae yeast. The dogs were fed a lower protein and fiber diet for 21 days and then changed to a higher protein and fiber diet until day 49. Yeast supplementation did not statistically influence diet digestibility. The probiotic group had a lower fecal concentration of total biogenic amines (days 21 and 49), ammonia (day 23), and aromatic compounds and a higher fecal concentration of butyrate (p < 0.05). The probiotic group showed a lower dysbiosis index, a higher abundance (p < 0.05) of Bifidobacterium (days 35 and 49) and Turicibacter, and a lower abundance of Lactobacillus and E. coli (p < 0.05). Beta diversity demonstrated a clear differentiation in the gut microbiota between the control and probiotic groups on day 49. The control group showed upregulation in genes related to virulence factors, antibiotic resistance, and osmotic stress. The results indicated that the live yeast evaluated can have beneficial effects on intestinal functionality of dogs.
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We aimed to evaluate the effects of an herbal source of choline on the coefficients of total tract apparent digestibility (CTTAD), diet palatability, fecal characteristics, blood variables, liver morphology, and cardiac function of dogs. Sixteen adult dogs were randomly assigned to two groups (n = 8) which were fed two different diets for 45 days: control, containing 0.28% choline chloride 60, and test, containing 0.14% of an herbal source of choline. Feces were collected between days 39 and 44 to determine nutrient CTTAD and fecal characteristics. On days 0 and 45, blood samples were collected and the liver morphology was evaluated. Cardiac function, in turn, was evaluated only on day 45, and the palatability test was performed on two consecutive days (n = 32). There were no changes in nutrient CTTAD, diet palatability, or fecal characteristics of dogs fed the test diet (p > 0.05). However, on day 45, dogs fed the test diet showed lower (p < 0.05) serum total cholesterol, triglycerides, alkaline phosphatase, and alanine aminotransferase when compared to the control group. We concluded that the herbal source of choline can be a possible substitute for choline chloride in dog nutrition.
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This research aimed to evaluate the apparent total tract digestibility (ATTD) of nutrients, metabolisable energy (ME) and palatability of the diet, as well as products of intestinal fermentation and faecal microbiota of dogs fed with dried apple. For this purpose, three experiments were performed. In Experiment I, digestibility and ME of four diets containing 0%, 3%, 6% and 9% dried apple were evaluated, in addition to the faecal characteristics of the dogs. The diets were offered to eight adult dogs, distributed in double Latin square (4 × 4), totalling eight repetitions per treatment. In Experiment II, products of intestinal fermentation and faecal microbiota from 16 adult dogs fed diets containing 0% and 9% dried apple for 30 d (n = 8) were evaluated. Finally, Experiment III compared the dietary preference of 0 vs. 9% dried apple using 15 adult dogs. The inclusion of dried apple in the diet (p < 0.05) showed a linear reduction in the ATTD of dry matter (DM), crude protein (CP), and acid hydrolysed ether extract (EEA), and a linear increase in the ATTD of total dietary fibre (TDF). Consumption of 9% of dried apple increased faecal butyrate and reduced propionate and ammonia (p < 0.05). With this diet, there was also an increase (p < 0.05) in the faecal concentration of Faecalibacterium, Erysipelatoclostridium, Blautia, and Bacteroides. No differences were found in the palatability of the diets. The inclusion of up to 9% of dried apple in the diet reduces the digestibility of nutrients and does not influence the dogs' food preference; however, it improves some indicators of dogs' intestinal functionality.
Asunto(s)
Butiratos/metabolismo , Heces/química , Microbioma Gastrointestinal , Malus/química , Alimentación Animal/análisis , Animales , Dieta/veterinaria , Perros , Relación Dosis-Respuesta a Droga , Femenino , Alimentos en Conserva/análisis , Microbioma Gastrointestinal/efectos de los fármacos , Masculino , Distribución AleatoriaRESUMEN
BACKGROUND: Direct-fed microbials (DFM), such as Bacillus subtilis and Bacillus licheniformis, may improve gut functionality of the host by favouring non-pathogenic bacteria and reducing the formation of putrefactive compounds. The aim of this study was to assess the nutrient digestibility, faecal characteristics and intestinal-fermentation products in dogs fed diets with Bacillus subtilis and Bacillus licheniformis. Sixteen dogs were randomly divided into two groups. Every eight dogs were fed with the control diet or the diet with the addition of 62.5 g of DFM (B. subtilis and B. licheniformis)/ton. Diets were provided throughout a 20-day adaptation period, followed by 5 days of total faecal collection. Nutrient digestibility and the metabolisable energy of the diets, plus the dogs' faecal characteristics and intestinal fermentation products were assessed. RESULTS: There were no differences in nutrient digestibility (P > 0.05). However, DFM supplementation improved faecal score and resulted in less fetid faeces (P < 0.001). DFM inclusion reduced (P < 0.05) the biogenic amines concentration: putrescine, spermidine and cadaverine, besides the concentration of phenols and quinoline. CONCLUSIONS: The use of B. subtillis and B. licheniformis as DFM reduce the concentration of nitrogen fermentation products in faeces and faecal odour, but the digestibility of nutrients is not altered in dogs.
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Alimentación Animal/microbiología , Bacillus licheniformis/fisiología , Bacillus subtilis/fisiología , Perros/fisiología , Heces/química , Animales , Aminas Biogénicas/análisis , Dieta/veterinaria , Proteínas en la Dieta/metabolismo , Digestión/fisiología , Perros/microbiología , Fermentación , Odorantes , Probióticos , Distribución AleatoriaRESUMEN
The objective of this study was to evaluate the effects of the microalgae Schizochytrium sp., as a dietary source of docosahexaenoic acid (DHA), on diet palatability, coefficients of total tract apparent digestibility (CTTAD) of nutrients and metabolizable energy (ME), blood variables and indicators of immunity in dogs. We also evaluated oxidative stability. Two diets containing 0 and 0.4% of microalgae Schizochytrium sp. were evaluated in three experiments. On Experiment I the palatability of diets containing 0% versus 0.4% microalgae was compared. In Experiment II test diets were offered for 30 days to determine digestibility, fecal characteristics, and blood parameters. In Experiment III, the oxidative stability of diets containing microalgae versus anchovy oil was evaluated. There was a higher intake ratio of the diet containing microalgae (p < .05). The ME and CTTAD of nutrients increased (p < .05), except for ether extract after acid hydrolysis, with the inclusion of the microalgae in diet. The amount of monocytes and phagocytic granulocytes was higher (p < .05) in dogs fed 0.4% microalgae. There was greater oxidative stability for the sample containing microalgae. The addition of 0.4% microalgae presented high palatability, increased phagocytic cell numbers, and demonstrated oxidative stability superior to anchovy oil.
Asunto(s)
Dieta , Ácidos Docosahexaenoicos/farmacología , Microalgas , Animales , Antioxidantes , Células Sanguíneas/efectos de los fármacos , Análisis Químico de la Sangre , Dieta/veterinaria , Digestión/efectos de los fármacos , Perros , Metabolismo Energético/efectos de los fármacos , Heces , Inmunidad/efectos de los fármacos , Inflamación/tratamiento farmacológico , Inflamación/veterinaria , Microalgas/químicaRESUMEN
ABSTRACT: The objective of the present study was to evaluate the digestibility and the immunomodulatory effects of diets supplemented with lutein in dogs. Sixteen adult dogs were distributed in two groups (control and test) in a completely randomized design. Dogs were fed for 120 days with iso-nutritive diets, which only difference was the inclusion of 45g lutein/kg in the diet fed to the test group. Blood samples were collected in the beginning and at the end of the experimental period to evaluate total lymphocyte, lymphocyte proliferation index, and CD4+ and CD8+ lymphocyte counts. In order to evaluate apparent diet digestibility, dogs were housed in metabolic cages for ten days (five days of adaptation and five for faeces total collection). Coefficients of total tract apparent digestibility were not different between dogs in the control and the lutein-fed groups. Lutein dietary supplementation did not influence total lymphocyte or lymphocyte proliferation index, but resulted in higher CD4+ and CD8+ lymphocyte numbers. Lutein supplementation did not affect diet digestibility or lymphocyte proliferation index in dogs. However, it increases the concentrations of CD4+ and CD8+ T-lymphocyte subtypes.
RESUMO: O objetivo do presente estudo foi avaliar a digestibilidade e os efeitos imunomoduladores de dietas suplementadas com luteína em cães. Dezesseis cães adultos foram distribuídos em dois grupos (controle e teste), em delineamento inteiramente casualizado. Os cães foram alimentados durante 120 dias com dietas iso-nutritivas, diferindo apenasna inclusão de 45g de luteína/kg na dieta do grupo teste. As amostras de sangue foram colhidas no início e no final do período experimental para avaliar o total de linfócitos, o índice de proliferação de linfócitos e a contagem de linfócitos CD4 + e CD8 +. Para avaliar a digestibilidade aparente da dieta, os cães foram alojados em gaiolas metabólicas por dez dias (cinco dias de adaptação e cinco para coleta total de fezes). Os coeficientes de digestibilidade aparente não foram diferentes entre cães do grupo controle e os alimentados com luteína. A suplementação dietética com luteína não influenciou a contagem de linfócitos totais ou o índice de proliferação de linfócitos, mas resultou em número de linfócitos CD4 + e CD8 + mais elevadas. A suplementação de luteína não afeta a digestibilidade da dieta ou o índice de proliferação de linfócitos em cães. No entanto, aumenta as concentrações dos subtipos CD4 + e CD8 + de linfócitos T.
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A glicerina é um coproduto originado da produção de biodiesel, que apresenta possibilidade de uso como fonte energética na nutrição animal. Objetivou-se avaliar os coeficientes de digestibilidade aparente (CDA) e a energia metabolizável (EM) de dietas contendo glicerina, bem como a EM da glicerina em cães. Foram avaliadas quatro dietas contendo crescentes níveis de glicerina: 0%, 3%, 6% e 9%. As dietas foram fornecidas a oito cães adultos, os quais foram distribuídos em delineamento Quadrado Latino duplo (4x4). A adição de glicerina aumentou os CDA da matéria seca, energia bruta e a EM, sem afetar os CDA da proteína bruta e dos extrativos não nitrogenados da dieta. Entretanto, resultou em redução no CDA do extrato etéreo da dieta. Embora a adição de glicerina tenha reduzido o teor de matéria seca fecal, não houve efeito sobre o escore das fezes. Dentro dos níveis avaliados, a glicerina pode ser utilizada na dieta como fonte energética altamente disponível para cães.
Glycerin is a by-product originated from biodiesel production and it is an energetic ingredient of increasing possibility of use in diets of different species. This study aimed to evaluate the digestibility in dogs fed diets containing increasing levels of glycerol (0%, 3%, 6% and 9%). Diets were fed to eight adult dogs, which were distributed in Latin square design (4x4). The glycerol addition in the diet increased the digestibility of dry matter, gross energy and metabolizable energy, without affecting the digestibility of crude protein and nitrogen free extract. However, resulted in lower digestibility of ether extract. Although the addition of glycerin has reduced the amount of fecal dry matter, had no effect on fecal score. Within the levels evaluated, the glycerin can be used as dietary energy source highly available for dogs.
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Objetivou-se avaliar diferentes metodologias de determinação da digestibilidade em cães, alimentados com duas dietas contendo fontes proteicas animal (farinha de vísceras de aves - FVA) e vegetal (farelo de soja - FS). As metodologias avaliadas foram: colheita total de fezes (CTF) e os indicadores cinza insolúvel em ácido (CIA), fibra em detergente ácido (FDA) e fibra bruta (FB). Foram utilizados 8 cães adultos, em delineamento Cross over, em parcela subdividida no tempo (parcela: fontes proteicas; e subparcela: metodologias de digestibilidade). O período experimental foi constituído por cinco dias de adaptação, com cinco dias de colheita total de fezes. A dieta contendo FS apresentou maior CDA da PB, enquanto a dieta contendo FVA apresentou maior CDA dos demais nutrientes e energia metabolizável (EM). Os CDA e EM determinados pela CTF e pelos indicadores não diferiram entre si, podendo ser determinados pelos indicadores FB, FDA e CIA, independentemente da fonte proteica da dieta.
The objective was to evaluate different methods of measuring digestibility in dogs fed two diets containing animal (poultry by products - PBP) and vegetable (soybean meal - SBM) protein sources. The methods evaluated were: total fecal collection (TFC) and indicators: acid insoluble ash (AIA), acid detergent fiber (ADF) and crude fiber (CF). Eight dogs were distributed in Cross Over in split plots (plot: sources of protein; subplot: methods for digestibility), fed by five days of adaptation and five days of total fecal collection. The diet containing SBM had a higher ADC of CP, while the diet containing POM showed higher ADC of all nutrients and metabolizable energy (ME). The ADC and ME determined by the TFC and the indicators did not differ. Thus, the ADC of diets in dogs can be determined by TFC and CF, ADF and AIA indicators, regardless of source of dietary protein.
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A soja é um grão rico em proteínas e lipídeos, a partir do qual se obtém diversos derivados proteicos de alto valor nutricional. Em virtude disso, realizou-se este estudo com o objetivo de analisar a composição bromatológica de derivados proteicos de soja, bem como as características físico-químicas dos extrusados formados a partir destes. Foram formuladas seis dietas para cães, uma referência e cinco contendo 30 por cento de derivados de soja (farinha desengordurada - FDS, micronizada, farelo, grão integral e grão tostado), as quais foram extrusadas. Os derivados de soja e as dietas foram submetidos a análises bromatológicas e de qualidade do processamento. A FDS e o farelo de soja apresentaram os maiores teores de proteína bruta, enquanto os grãos de soja integral e tostado e a soja micronizada apresentaram os maiores teores de extrato etéreo em hidrólise ácida e energia bruta. A soja grão integral apresentou a maior atividade ureásica e inibitória de tripsina, mesmo após a extrusão da dieta. Os extrusados contendo as sojas grão e micronizada apresentaram as maiores densidades e as menores durezas, índice de absorção de água e grau de gelatinização do amido. Derivados proteicos de soja apresentam alto valor nutricional, entretanto, devem ser termicamente processados antes da extrusão para completa inativação do inibidor de tripsina. Além do mais, derivados contendo alto teor de lipídeos, como soja grão e micronizada, quando adicionados em 30 por cento da fórmula, comprometem a qualidade do extrusado.
Soy is a grain rich in protein and lipids, from which its obtained different protein products of high nutritional value. This study aimed to analyze the chemical composition of different soy-protein products, as well as the characteristics of the extruded produced. Six diets were formulated, a reference and five with 30 percent soy product (defatted soy flour - DSF, micronized, soybean meal, crude grain or toasted grain), which were extruded. Soy products and diets were submitted to chemical analyses and process quality. The DSF and soybean meal presented the highest crude protein content, while the toasted and crude soybeans and micronized soy presented the highest acid hydrolyses ether extract and crude energy content. The crude soybean presented the highest ureatic activity and trypsin inhibitor activity, even after the diet extrusion. The soy beans and micronized soy extruded presented the highest density and the lowest hardness, water absorption index and starch gelatinization degree. Soy-protein products present high nutritional value, however they should be heated before extrusion to complete inhibition of trypsin inhibitor. Besides, soy products with high fat content, such as soybean and micronized soybean, when added to 30 percent reduced the extruded quality.
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Considering the benefice demonstrated by the modulating action of probiotics on the host intestinal microbiota, this study aimed to evaluate diet digestibility and fecal characteristics of dogs fed with diets supplemented with Bacillus subtilis (C-3102). Twelve young Beagle dogs were distributed in a completely randomized experimental design consisting of two treatments: diet with no addition or with the addition of 0.01 percent Bacillus subtilis (C-3102). Dogs passed through 25 days of adaptation to the diets, and five days of total feces collection. The following fecal characteristics were evaluated: pH, fecal score (1 - watery feces; 5: dry and hard feces), and ammonia content. Diet mean digestibility was compared by the Tukey test, and fecal characteristics by the Tukey-Kramer test. Diet digestibility was not different between treatments, but dogs supplemented with the tested probiotic presented dryer feces (39.1 percent vs. 36.5 percent dry matter), higher fecal score (3.4 vs. 3.0) and lower fecal ammonia content (0.45 percent vs. 0.56 percent), than dogs fed with the control diet. The dietary supplementation with Bacillus subtilis (C-3102) improves fecal texture and odor in dogs.
Em virtude da capacidade moduladora dos probióticos sobre a microbiota intestinal a favor da saúde do hospedeiro, objetivou-se, com este estudo, avaliar a digestibilidade e as características das fezes de cães suplementados com Bacillus subtilis (C-3102) na dieta. Foram utilizados 12 cães adultos da raça Beagle, os quais foram distribuídos inteiramente ao acaso, em dois tratamentos: dieta controle e dieta com adição de 0,01 por cento de Bacillus subtilis (C-3102). Os animais passaram por 25 dias de adaptação às dietas e por cinco dias para colheita total de fezes. As características das fezes foram avaliadas por meio da matéria seca, do escore (1: fezes moles, malformadas a 5: fezes secas e duras), do pH, da amônia e da produção de fezes. Não houve diferença na digestibilidade; entretanto, os cães suplementados com probiótico apresentaram fezes mais secas (39,1 por cento vs. 36,5 por cento de matéria seca), com maior escore (3,4 vs. 3,0) e menor teor de amônia (0,45 por cento vs. 0,56 por cento), quando comparados com os alimentados com a dieta controle. A suplementação com Bacillus subtilis (C-3102) melhora a consistência e diminui o odor das fezes dos cães.
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As características físicas da dieta, dentre elas a granulometria, exercem importante papel no aproveitamento da dieta pelos animais. Desse modo, o presente estudo teve como objetivo avaliar os efeitos da granulometria da dieta sobre a digestibilidade e a metabolizabilidade da energia de rações secas extrusadas para cães. Oito cães adultos da raça Beagle foram distribuídos em delineamento quadrado latino duplo (4 x 4), totalizando oito repetições no tempo. Os ingredientes foram moídos em peneiras de 0,8; 1,0; 1,2 e 1,5mm, resultando em rações com diâmetro geométrico médio (DGM) de 468, 476, 499 e 588µm, respectivamente. Cada período experimental foi composto por cinco dias para adaptação às dietas e cinco dias de coleta total de fezes. As análises de correlação e regressão linear demonstraram relação negativa entre o DGM e os coeficientes de digestibilidade aparente (CDA) da proteína bruta (y=94,82-42,05x), o extrato etéreo em hidrólise ácida (y=86,57-35,02x), os extrativos não nitrogenados (y=102,48-48,42x) e a energia metabolizável (y=3597,56-1697,00x). Não foi observado efeito do DGM sobre o consumo de matéria seca e o CDA da matéria seca. Houve piora na qualidade das fezes à medida que o DGM das dietas aumentou. Portanto, a menor granulometria da ração está relacionada ao melhor aproveitamento dos nutrientes e à energia da dieta e à produção de fezes de melhor qualidade pelos cães.
The physical characteristics of the diet, including particle size, exert important role in animals diet usage. So, the current study aimed to evaluate the effect of diet granulometry on nutrients digestibility and metabolizability of energy in dogs. Eight adult Beagle dogs were distributed in a double latin square design (4 x 4), totaling eight replicates in time. The ingredients of diets were ground in sieves of: 0.8, 1.0, 1.2 and 1.5mm, and the diets particle size were expressed as geometric mean diameter (GMD): 468, 476, 499 and 588µm, respectively. Each experimental period was composed by five days for diet adaptation and five days of total feces collection. The correlation and regression analyses showed a negative relationship between GMD and coefficient of apparent digestibility (CAD) of crude protein (y=94.82-42.05x), acid ether extract (y=86.57-35.02x), nitrogen free-extract (y=102.48-48.42x) and metabolizable energy (y=3597.56-1697.00x). It was not observed effect of GMD on dry matter intake and dry matter CAD. There was lower fecal score with increasing GMD of foods. Therefore, the lowest particle size of food resulted in better use of nutrients and diet energy and production of drier feces by dogs.
RESUMEN
As vitaminas são micronutrientes que participam de inúmeros processos metabólicos do organismo, sendo, portanto, essenciais para ótima saúde e desempenho do animal. Poucos trabalhos foram realizados nos últimos anos para estimar os melhores níveis de vitaminas para frangos, havendo grande variação entre os níveis empregados comercialmente. Sendo assim, o objetivo deste trabalho é apresentar os conceitos atuais na avaliação das exigências de vitaminas para frangos e os níveis sugeridos pela indústria e pelo meio científico. A maioria dos níveis recomendados pelo NRC (1994) foi baseada em trabalhos antigos, realizados em condições controladas e considerando os níveis mínimos para evitar sinais de deficiência, não avaliando o melhor desempenho nas condições de desafio encontradas a campo. Além disso, as linhagens atuais apresentam maior taxa de crescimento e produção, resultando em maior necessidade nutricional para expressar seu potencial genético. Atualmente, além dos índices zootécnicos, têm se avaliado outros parâmetros na determinação das exigências de vitaminas, tais como imunidade, bem-estar e características da carcaça. Os níveis vitamínicos empregados comercialmente são geralmente superiores aos preconizados pelo NRC (1994), sendo que os níveis das lipossolúveis podem superar até 25 vezes as recomendações e os das hidrossolúveis até cinco vezes. O uso de maiores níveis de vitaminas na dieta de frangos resulta em maior desempenho produtivo e qualidade da carne.
Vitamins are micronutrients that participe in many metabolic processes of the organism, being essential to animal health and performance. There has been little research conducted over the last years on estimating the best vitamin levels for broilers, having great variation on comercial levels. The objective of this study was to present the actual concepts of the evaluation of vitamin requirements for broiler and the levels recomendated by industry and research centers. The major levels recomendated by NRC (1994) were based on former studies, with controled conditions and considering minimal levels to avoid deficiency signs, not evaluating the best performance on the challenge conditions found in field. Furthermore, modern strains presents greater growth rate and production, resulting in higher nutritional requirements to express their genetical potential. Nowadays, besides zootecnical parameters, it had been evaluating other parameters to determine vitamin requirements, as imunity, well being and carcass characteristics. Comercial vitamin levels used are generally superior than the suggested by NRC (1994), and the liposolubles levels may be higher than 25 times the recomendations and hydrosolubles five times higher. The use of higher vitamin levels in brolier diet results in greater productive performance and meat quality.