Composição químico-bromatológica, produção de gás, digestibilidade in vitro da matéria seca e NDT estimado da silagem de sorgo com diferentes proporções de panículas

Abstract

RESUMO -Foram objetivos do presente trabalho avaliar as alterações na composição bromatológica, nas frações nitrogenadas e de carboidratos, estimar a taxa de digestão dos carboidratos fibrosos (CF) e não-fibrosos (CNF), determinar a digestibilidade in vitro da matéria seca (DIVMS) e estimar o NDT da silagem de sorgo com as seguintes proporções de panículas: 0, 20, 40, 60, 80 e 100%. Foram determinados os teores de matéria seca (MS), proteína bruta (PB), extrato etéreo (EE), matéria mineral (MM), fibra em detergente neutro (FDN), as frações protéicas: NNP, B 1 +B 2 , B 3 e C, e os carboidratos não fibrosos (CNF) e as frações B 2 e C dos carboidratos totais. As taxas de digestão das frações dos carboidratos totais foram estimadas por meio da técnica de produção de gás, a digestibilidade in vitro da matéria seca (DIVMS) pela técnica de dois estágios e o NDT estimado pela composição bromatológica. O acréscimo de panículas à silagem de sorgo aumentou linearmente os teores de MS, PB, CNF, EE e lignina na FDN e, reduziu os teores de MM e FDN. O NNP e as frações B1+B2, B 3 e C variaram de 9,19 a 21,24, de 67,63 a 75,98, de 3,85 a 6,09 e de 5,09 a 10,98% do N total. Os teores dos CNF aumentaram linearmente e da fração B 2 dos carboidratos totais foram reduzidos, os quais variaram de 208,18 a 564,07 e de 381,29 a zero g/kg de MS, respectivamente. As taxas de digestão dos CNF e da fração B 2 variaram de 0,1358 a 0,1563h -1 e de 0,0247 a 0,0294 h -1 . O volume final de gás não foi influenciado pela adição de panículas e a DIVMS máxima de 69,52% foi obtida com 60,10% de panículas. Embora o NDT estimado tenha aumentado linearmente, considerando a não alteração da produção de gás e o comportamento quadrático da DIVMS, pode-se inferir que a utilização destas estimativas não parece adequada.Palavras-chave: cinética, digestão, frações protéicas e carboidratos Chemical Composition, Gas Production, In Vitro Dry Matter Digestibility and TDN Estimate of Sorghum Silage with Different Panicle ProportionsABSTRACT -This work had as objective to evaluate the chemical composition alteration in the nitrogen and carbohydrate fractions, to estimate the digestion rate of fiber carbohydrates (FC) and non-fiber carbohydrates (NFC), to determine the in vitro dry matter digestibility (IVDMD) and to estimate the TDN of sorghum silage with different panicle proportions (0, 20 , 40, 60, 80 and 100%). The contents of dry matter (DM), crude protein (CP), ether extract (EE), ash, neutral detergent fiber (NDF), nitrogen fractions: NPN, B1+B2, B 3 and C, non-fiber carbohydrate (NFC) and B 2 and C fractions of total carbohydrates were determined. The digestion rates of the NFC and B 2 fractions of total carbohydrates were estimated by in vitro gas production technique, the IVDMD was determined by two-stage technique and TDN, by chemical composition. The increase in the panicle in sorghum silage increased linearly the amounst of DM, CP, NFC, EE and lignin in NDF and reduced the ash and NDF amount. The NPN and the B1+B2, B3 and C fractions ranged from 9.19 ...

Divergence of the fermentative and bromatological characteristics of 25 sorghum hybrid silages

“…The values observed in this study corroborated with the literature data (Rocha Jr. et al, 2000;Cândido et al, 2002;Molina et al, 2002;Rodrigues et al, 2002;Neumann et al, 2005;Skonieski et al, 2010).…”

“…The average concentration of CP was 6.47 dag/kg DM in the silage hybrids, higher than those observed by Skonieski et al (2010) and Cabral et al (2003), of 6.10 and 5.53 dag/kg DM, respectively. For Neumann et al (2002b), variations in the proportion of stems, leaves, and panicles of sorghum plants are the main responsible for variations in the protein content between different hybrids, since the appropriate fermentation profile minimizes losses of nutrients during the fermentation process.…”

“…Ribeiro et al (2007), evaluating sorghum hybrids, observed proper fermentation profile of the silage in terms of DM content, crude protein, ammonia nitrogen in relation to total nitrogen and pH, with values of 32.65, 6.82, 1.92 and 4.02, respectively. The nutritional value of sorghum silage depends on the characteristics of the hybrid used, such as height, percentage of panicles, stem and leaf, and the stage of maturity at harvest (Cândido et al, 2002). Therefore, the objective was to evaluate the divergences of bromatological and fermentation characteristics of the silages of 25 sorghum hybrids.…”

Fermentation characteristics of different purpose sorghum silage

“…Cabral et al (2003), evaluated the nutritive value of sorghum silages and observed a linear increase in DM content with an increment in panicle ratio, which helps to explain the results obtained.…”

Nutritional divergence in genotypes of forage peanut

“…These high values for VF1 are due to the higher NFC content presented by these genotypes (Table 2), conferring greater availability of fermentable substrate and providing greater gas production for this fraction. Degradation rates for the rapidly degradable fraction (C1) were low, averaging 0.068/h, since reports of values from 0.1 to 0.2/h, are frequent (Cabral et al, 2003;Senger et al, 2007;Detmann et al, 2009). The highest gas productions from the fermentation of the slowly degradable fraction (VF2) were found for accessions 31828 and 31534.…”