Influence of the diet on in situ disappearance of dry matter, organic matter, and neutral detergent fiber of hydrolysed sugar cane bagasse

The effects of two diets based on hydrolysed sugarcane bagasse (HSB) and whole cottonseed (WCS), with or without oat hay, were analyzed for the in situ disappearance of dry matter (DM), organic matter (OM) and neutral detergent fiber (NDF) of HSB. Six mature castrated rams with a permanent T ruminai cannula were used in a complete randomized split plot design. The incubation times were 3, 6, 9, 12, 24, 48 and 72h. The diet with oat hay showed higher disappearance indexes for the NDF fraction. Furthermore, the maximum degradation of HSB constituents was reached around 48h of incubation. The diets were T1=64% hydrolyzed sugarcane + 36% whole cottonseed and T2=14% hydrolyzed sugarcane bagasse + 36% cottonseed + 50% oat hay.

Ruminal degradability of neutral detergent fiber of Cynodon spp. grasses at four regrowth ages

The aim of this work was to determine ruminal degradation of neutral detergent fiber of grasses of the genus Cynodon, harvested at four cutting ages. It was used a randomized block design, with five treatments arranged in a split plot, the five evaluated genotypes: Tifton 85, Jiggs, Russel, Tifton 68 and Vaquero; were the plots and ages of cutting were the subplots: 28, 48, 63 and 79 days. By adding one day in the cutting age, there was a linear reduction in the effective degradability of neutral detergent fiber of blade and stem of 0.16 and 0.18%, respectively. The increase in the cutting age had a linear and positive influence on the undegradable neutral detergent fiber with daily increments for leaf and stem of 0.12 and 0.18%, respectively. At the 28 regrowth day, all genotypes showed higher content of potentially degradable insoluble fraction, effective degradability and lower undegradable fraction of the neutral detergent fiber of blade and stem in relation to other ages, in this way this interval is recommended for cutting management.

Reutilization of chemical waste in methodologies for analyses of neutral detergent fiber and acid detergent fiber

The disposal of chemical waste and the precision of analyses of the neutral (NDF) and acid (ADF) detergent fiber contents were evaluated utilizing conventional (Van Soest) and alternative methods of analyses. The recovery of acetone promoted both economic and environmental gains, with a recovery rate of 84.12%. The precision of the analyses was not observed in most of the determinations with reutilization of chemical waste in all the analytical methods tested, in spite of promoting decrease in cost, time invested in the preparation of solutions and the disposal of chemical waste.

Evaluation of lignin contents in tropical forages using different analytical methods and their correlations with degradation of insoluble fiber

We compared the lignin contents of tropical forages by different analytical methods and evaluated their correlations with parameters related to the degradation of neutral detergent fiber (NDF). The lignin content was evaluated by five methods: cellulose solubilization in sulfuric acid [Lignin (sa)], oxidation with potassium permanganate [Lignin (pm)], the Klason lignin method (KL), solubilization in acetyl bromide from acid detergent fiber (ABLadf) and solubilization in acetyl bromide from the cell wall (ABLcw). Samples from ten grasses and ten legumes were used. The lignin content values obtained by gravimetric methods were also corrected for protein contamination, and the corrected values were referred to as Lignin (sa)p, Lignin (pm)p and KLp. The indigestible fraction of NDF (iNDF), the discrete lag (LAG) and the fractional rate of degradation (kd) of NDF were estimated using an in vitro assay. Correcting for protein resulted in reductions (P < 0.05) in the lignin contents as measured by the Lignin (sa), Lignin (pm) and, especially, the KL methods. There was an interaction (P < 0.05) of analytical method and forage group for lignin content. In general, LKp method provided the higher (P < 0.05) lignin contents. The estimates of lignin content obtained by the Lignin (sa)p, Lignin (pm)p and LKp methods were associated (P > 0.05) with all of the NDF degradation parameters. However, the strongest correlation coefficients for all methods evaluated were obtained with Lignin (pm)p and KLp. The lignin content estimated by the ABLcw method did not correlate (P > 0.05) with any parameters of NDF degradation. There was a correlation (P < 0.05) between the lignin content estimated by the ABLadf method and iNDF content. Nonetheless, this correlation was weaker than those found with gravimetric methods. From these results, we concluded that the gravimetric methods produce residues that are contaminated by nitrogenous compounds. Adjustment for these contaminants is suggested, particularly for the KL method, to express lignin content with greater accuracy. The relationships between lignin content measurements and NDF degradation parameters can be better determined using KLp and Lignin (pm)p methods. (C) 2011 Elsevier B.V. All rights reserved.

Acurácia, precisão e robustez das estimativas da digestibilidade aparente da matéria seca determinada com o uso de indicadores em ovinos

O objetivo foi avaliar a acurácia, precisão e robustez das estimativas da digestibilidade aparente da matéria seca obtidas utilizando-se como indicadores fibra em detergente ácido indigestível (FDAi), fibra em detergente neutro (FDNi) indigestível, lignina em detergente ácido (LDA), LDA indigestível (LDAi) e óxido crômico em comparação ao método de coleta total de fezes. Dezoito ovinos (56,5 ± 4,6 kg PV) foram designados aleatoriamente a dietas compostas de 25, 50 ou 75% de concentrado e feno de Coast cross por 25 dias. As fezes foram coletadas por cinco dias para determinação da digestibilidade aparente da MS. As amostras de alimentos e fezes foram incubadas no rúmen de três bovinos por 144 horas, para obtenção das frações indigestíveis. Óxido crômico foi administrado a 4,0 g/animal/dia. A acurácia foi avaliada pela comparação do viés médio (DAMS predito - DAMS observado) entre os indicadores; a precisão, por meio da raiz quadrada do erro de predição e do erro residual; e a robustez, pelo estudo da regressão entre o viés e o consumo de matéria seca, o nível de concentrado e o peso vivo. A recuperação fecal e a acurácia das estimativas da digestibilidade aparente da MS foram maiores para FDAi, seguida pela FDNi, LDAi, pelo óxido crômico e depois pela lignina em detergente ácido. O viés linear foi significativo apenas para FDAi, FDNi e LDAi. O uso de óxido crômico permitiu estimativas mais precisas da digestibilidade aparente da MS. Todos os indicadores foram robustos quanto à variação no consumo de matéria seca e apenas LDAi e óxido crômico foram robustos quanto aos níveis de concentrado na dieta. O óxido crômico não foi robusto quando houve variação no peso vivo animal. Assim, a FDAi é o indicador mais recomendado na estimativa da digestibilidade aparente da MS em ovinos quando o objetivo é comparar aos dados da literatura, enquanto o óxido crômico é mais recomendado quando o objetivo é comparar tratamentos dentro de um mesmo experimento.

Comparação de marcadores de fase sólida para medir fluxo de matéria seca e matéria orgânica no duodeno

Two external markers (chromic oxide and ytterbium chloride) and two internal markers (indigestible neutral detergent fiber-NDF and indigestible acid detergent fiber-ADF) were compared in order to determine the flow of dry and organic matter in the duodenum. Three steers with ruminal and duodenal cannulas were fed with roughage: concentrate ratios of 80:20 60:40 and 40:60. As these ratios as well as animals and experimental periods did not show significant effects, only markers will be discussed the flow of the duodenal dry matter were 3816.8, 3269.3, 2739.2 and 2713.2g/day and of the organic matter were 3305.1, 2841.6, 2392.2 and 2351.3g/day estimated by chromic oxide, ytterbium chloride, indigestible NDF and indigestible ADF, respectively. The coefficients of ruminal digestion of the dry matter expressed as a percentage of the total digested were 38.8, 57.8, 80.2 and 81.9% and organic matter were 48.4, 65.3 84.8 and 85.7, when estimated by chromic oxide, ytterbium chloride, indigestible NDF and indigestible ADF, respectively. Ir was concluded that different markers lead to different estimation of duodenal flow and indigestible NDF and indigestible ADF are equivalent markers.

Estimation of fecal production, digesta flow and digestibility in dairy heifers with different indicator

Objetivou-se com este trabalho avaliar a produção fecal por meio do indicador interno, fibra em detergente neutro indigestível (FDNi), e externos, cromo complexado com ácido etilenodiaminotetracético (Cr-EDTA ) e o cloreto de itérbio (YbCl3), além de estimar o fluxo duodenal da matéria seca e os coeficientes de digestibilidades aparentes total, ruminal e pós-ruminal, de diferentes nutrientes. Foram utilizadas oito novilhas mestiças Holandês/Zebu, distribuídas em duplo quadrado latino 4 x 4. Os indicadores Cr-EDTA, YbCl3 e o FDNi não estimaram produção fecal de forma eficiente (p < 0,05), obtendo resultado de 1,64; 1,71 e 2,71 kg dia-1, respectivamente, quando comparado à coleta total de fezes, que obteve resultado de 1,39 kg dia-1. Os valores estimados de fluxo de matéria seca, tanto para a metodologia de único, quanto para de duplo indicador, podem ser considerados biologicamente aceitáveis. Contudo, o valor obtido pela associação Cr-EDTA/YbCl3, utilizada na forma de duplo indicador, foi o mais confiável, pela melhor recuperação dos indicadores externos (Cr-EDTA e YbCl3), que obtiveram médias de 89 e 85%, respectivamente, em comparação ao interno (FDNi), que obteve média 67%. Os coeficientes de digestibilidade ruminal e pós ruminal, estimados pela associação Cr-EDTA/YbCl3, foram considerados melhores, em consequência do valor de fluxo de matéria seca estimado por esta associação.

Digestibilidade e degradabilidade de rações à base de milho desintegrado com palha e sabugo em diferentes graus de moagem

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Produção Fecal e Fluxo Duodenal de Matéria Seca e Matéria Orgânica Estimados por Meio de Indicadores

O objetivo deste trabalho foi comparar os indicadores internos, fibra em detergente neutro e fibra em detergente ácido indigestíveis, obtidos após 144h de incubação in vitro e in situ (FDNiv; FDNis; FDAiv; FDAis) com o indicador externo, o óxido crômico (Cr2O3), para estimativas da produção fecal, do fluxo duodenal de matéria seca e matéria orgânica em novilhos mestiços (HxZ) confinados. Foram utilizadas dietas à base de silagens de milho, de raspa e de casca de mandioca, e também de cana-de-açúcar ensilada com polpa cítrica peletizada. Os novilhos foram castrados e canulados no rúmen e no duodeno. O período experimental teve 11 dias de adaptação às dietas e 8 dias de coleta. O delineamento experimental foi o quadrado latino (4x4), com quatro tratamentos, num arranjo em parcela subdividida, sendo as dietas estudadas nas parcelas, e os indicadores nas subparcelas. Os resultados obtidos em percentagem do peso vivo para a estimativa da produção fecal, utilizando-se os diferentes indicadores, mostraram que a FDAiv (0,88 %), a FDAis (0,85 %) e o Cr2O3 (0,99 %), embora com diferenças significativas, podem ser utilizados pelos resultados biologicamente consistentes. Para estimar o fluxo duodenal de matéria seca e matéria orgânica, foram utilizados os valores de produção fecal obtidos com a FDAiv. Os indicadores internos não apresentaram diferenças entre si para o fluxo duodenal de matéria seca, com média de 3,29 kg/dia, porém o óxido crômico superestimou o fluxo (4,95 kg/dia). Para o fluxo duodenal de matéria orgânica não houve diferença entre os indicadores com média de 2,73 kg/dia.

Desempenho ponderal de novilhas mestiças Holandês x Zebu submetidas a duas estratégias de suplementação mineral

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Indicadores na estimativa do fluxo de digesta em bovinos de corte

single and double marker methods were compared in seven Nellore steers with average body weight 250 kg, and previously canullated in the rumen and duodenum. The animals were fitted with continuous-infusion pump that administered CoEDTA solutions intraruminally. In addition, a capsule containing Cr 2O 3, and other, containing external n-alkanes C 32, C 36 were inserted into the rumen of each steer. Internal markers indigestible neutral-detergent fiber and acid-detergent fiber (iNDF and iADF after 144 h in situ incubation) and internal n-alkanes C 31, C 33, C 35 were components of the diet. Steers were fed with palisade grass (Brachiaria brizantha cv. marandu) in two age of regrowth, 30 and 60 days. The duodenal flow experimental design was a factorial 2×2×12 while omasal experimental design was a factorial 2×2×4. Markers iNDF, CoEDTA and the combination Co+iNDF were efficacious to estimate duodenal dry matter flow whereas iNDF, iADF and the Co+iADF combination were all efficacious to predict omasal dry matter flow. In conclusion, the double marker method for estimation of omasal and duodenal dry matter flow was the most appropriate considering the ruminal fiber digestibility.

Estimativa do fluxo de nutrientes pelo trato digestivo de bovinos de corte alimentados com Brachiaria brizantha (Hochst A. Rich) Stapf. cv. Marandu em duas idades de rebrota

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Isótopos estáveis de carbono em estudo com bovinos de corte em pastejo, suplementados no período da seca

Pós-graduação em Zootecnia - FMVZ

Qualidade dos fenos de capim-tifton 85 e alfafa sobre a biometria corporal e o desempenho esportivo de cavalos atletas na modalidade de três tambores

Pós-graduação em Zootecnia - FMVZ

Effects of Chemical Composition on Forage Intake of Heifers Fed Hays of Different Species

Alfalfa, smooth bromegrass, and big bluestem hays harvested at two maturities differing by four weeks were fed at mature-to-immature hay ratios of 1:0, 2:1, 1:2, and 0:1 to yearling heifers in an experiment with a three 4 x 4 Latin square design with 14 day periods. Concentrations of in vitro digestible dry matter and crude protein were greater and concentrations of neutral detergent fiber, acid detergent fiber, and indigestible neutral detergent fiber (determined by either a manual method with a 96 hour incubation or an automated method with a 48 hour incubation) were less in alfalfa hay than in the two grass hays and in smooth bromegrass hay than in big bluestem hay. Concentrations of in vitro digestible dry matter and crude protein decreased whereas those of neutral detergent fiber, acid detergent fiber and indigestible neutral detergent fiber increased with increasing forage maturity. Consumptions of dry matter, digestible dry matter, in vitro digestible dry matter, and crude protein were greater for heifers fed alfalfa hay diets than those fed the two grasses. Consumptions of total neutral detergent fiber and indigestible neutral detergent fiber, determined by the automated method with a 48 hour incubation, were greater by heifers fed diets containing big bluestem than those fed alfalfa or smooth bromegrass diets. Consumptions of acid detergent fiber and indigestible neutral detergent fiber, determined by a manual method with a 96 hour incubation, were greater for heifers fed alfalfa or big bluestem hay diets than those of heifers fed smooth bromegrass diets. Consumption of dry matter, in vivo or in vitro digestible dry matter, crude protein, neutral detergent fiber, acid detergent fiber and automated indigestible neutral detergent fiber decreased as the mature-to-immature hay ratio decreased. Diet digestibility was not affected by forage species, but increased as the mature-toimmature hay ratio decreased. Fecal excretion of dry matter and neutral detergent fiber did not differ between forage species or mature-to-immature hay ratios. Forage dry matter intake expressed as a percentage of body weight was significantly related to the concentrations of in vitro digestible dry matter (r2=.14), crude protein (r2=.17), neutral detergent fiber (r2=.20), and manual indigestible neutral detergent fiber (r2=.18) of the hays and the concentration of digestible dry matter of the diets (r2=.43).