Efeito de diferentes relações volumoso: concentrado no consumo, digestibilidade aparente e partição da digestão da dieta de bovinos

Three steers equipped with ruminal and duodenal cannulas were fed roughage:concentrate ratios 80:20, 60:40 and 40:60 in order to study intake and apparent, rumen and post-rumen digestibilities. The roughage was ''coast cross'' (Cynodon dactylon) hay (5.67% CP and 83.30% NDF). Undigestible neutral detergent fiber (NDF) was used as dry matter (DM) flow marker. DM intake means were 77.99, 91.03 and 91.81g DM/kg BW0.75, for the 20, 40 and 60% concentrate diets, respectively. DM intake for the 20% diet was statistically (P < 0.05) different from the other two diets. Apparent digestion coefficient (%) of DM (50.48, 57.32 and 61.33), organic matter (OM) (52.03, 58.91 and 62.76) and gross energy (GE) (48.95, 56.40 and 60.00) increased significantly with the increase in concentrate ratio of the diets. For the following components the apparent digestion coefficients were not statistically different: NDF (44.54, 45.28 and 42.53), ADF (40.69 44.39 and 43.60), cellulose (51.54, 54.34 and 52.03), hemicellulose (49.63, 46.78 and 39.18) and starch (86.59, 91.89 and 93.21). DM, OM, NDF, ATF, cellulose and starch ruminal and post-ruminal digestibilities were not statistically different. But the ruminal digestibilities of hemicellulose (94.81, 90.26 and 85.99) and EG (93.85, 83.30 and 78.77) decreased significantly as the concentrate ratio of the diets increased. The post-ruminal digestibility of hemicellulose (5.19, 9.74 and 14.03%) and GE (6.12, 16.20 and 21.23%) increased as the concentrate ratio of the diets increased.

Effect of tannin levels in sorghum silage and concentrate supplementation on apparent digestibility and methane emission in beef cattle

This study evaluated the effect of diets containing sorghum silages with higher (HT) and lower-tannin (LT) concentrations supplemented with concentrate or urea on intake, digestibility, ruminal digestibility, methane emission and rumen parameters in beef cattle. Four treatments were distributed according to a 2 x 2 factorial arrangement in a duplicate 4 x 4 Latin square: LT sorghum silage + urea, LT sorghum silage + concentrate, HT sorghum silage + urea, and HT sorghum silage + concentrate. Total digestibility of the organic matter was higher when concentrate was included in the diet (0.749 and 0.753 in the LT and HT treatments, respectively). It was observed lower ruminal apparent digested matter of neutral detergent fiber in HT diets. There was no effect of tannin levels on digestibility and methane emission. The supplementation with concentrate in the LT diet decreased gas losses as a function of gross energy intake in comparison to the supplementation of the diet with urea. These results suggest the potential of concentrate supplementation to minimize energy loss as methane emission by ruminants and increase the efficiency of energy utilization. (c) 2006 Elsevier B.V. All rights reserved.

Chemical Composition and fermentative characteristics of Elephant grass (Pennisetum purpureum Schum.) silages added of increasing levels of mango (Mangifera indica L.) byproducts

Aiming at evaluating the use of those byproducts on ruminant feeding an experiment has been carried out in the Forage Research department (www.npf.ufc.br), in order to evaluate the effects of addition of increasing levels of mango processing byproducts (MB) in Elephant grass silages. Twenty experimental silos made of PVC pipe (100 x 340 mm), in a completely randomized design with 5 levels of addition (0; 5; 10; 15; and 20%) of MB and 4 replications. Upon 32 days of ensilage, samples were collected for determination of levels of dry Matter (DM), crude protein (CP), ethereal extract (EE), neutral detergent fiber (NDF), acid detergent fiber (ADF), hemicelluloses (HC), ammonia nitrogen (N-NH3), and pH values. Data were evaluated by analyses of variance and regression analyses using the F test at the 5% level. The levels of DM and CP increased of 0.50 and 0.03 percentage units, respectively, for every 1% of MB added. The levels of NDF and ADF decreased of 0.51 and 0.24 percentage units, respectively, for every 1% of MB added. The levels of N-NH3 decreased from 4 to 23 percentage units while pH values remained constant (p>0.05), with average values of 3.29. Addition of 20% of MB improved silages chemical composition by promoting an increase in the levels of MS and reduction in the levels of fiber.

Valor nutritivo do feno de Brachiaria decumbens Stapf cv. Basilisk submetido a tratamento com amônia anidra ou uréia

The effects of the ammoniation of Brachiaria decumbens hay was evaluated. The hay bales were distributed into a complete randomized block design, with four replications and they were submitted to the treatments: untreated or treated with anhydrous ammonia (NH3)(2,0 and 3,0% of the DM) or with urea (3,6 and 5,4% of the DM). All the hays bales remained under plastic cover for 45 days. After three days of aeration, samples were collected for the determination of the chemical composition, nitrogenous compounds fraction and the in vitro dry matter (IVDDM) and organic matter (IVDOM) digestibility. In the metabolic study, Saanen goats breed was used in a 5x5 Latin squares design, where the apparent digestibility, the voluntary intake and the nutritive value index were evaluated. The ammoniation increased the contents of the total N, N ammonia (N-NH3) and non-protein N, with high effect on the levels of 3,0% of NH3 and 5,4% of urea. There were no differences between the level of 3,0% of NH3 and 5,4% of urea for the total N, N-NH3 and NPN. However, the treatment with 3,0% of NH3 allowed a larger fixation of N in ADIN and NDIN forms. The ammoniation increased the IVDMD and IVDMO and reduced the contents of neutral detergent fiber (NDF), hemicellulose, acid detergent fiber (ADF) and lignin, but it did not alter the cellulose and gross energy contents. The ammoniation increased the DM, OM, CP, NDF, ADF, hemicellulose, cellulose and gross energy apparent digestibility and as well as the voluntary intake of DM, digestible DM, digestible OM, digestible protein, digestible energy and the nutritive value index. The ammoniation increased the hay nutritive value index, but there were no differences between the levels of NH3 and urea.

Estimativas do Consumo e da Taxa de Passagem do Capim-Elefante (Pennisetum purpureum Schum.) sob Pastejo de Vacas em Lactação

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Food intake and digestive efficiency in temperate wool and tropic semi-arid hair lambs fed different concentrate: forage ratio diets

This work was conducted to evaluate food intake and digestive efficiency of temperate wool and tropic semi-arid hair lambs, according to different concentrate: forage ratios in diet. Twenty-four lambs, averaging 90 +/- 1.8 days old and a mean body weight of 20 +/- 0.69 kg, 12 of them wool lambs, F, from Ideal x Ile de France crossing, and 12 others pure Santa Ines hair lambs, were distributed into a four replication 3 x 2 factorial arrangement consisting of three diets and two genotypes. Experimental diets consisted of: D1 = 60% concentrate mix (C) and 40% Cynodon sp. cv. Tifton-85 hay (F), D2 = 40% C and 60% F, and D3 = 20% C and 80% F. D1 was formulated for a daily gain of 300g per animal. Increasing forage levels in diets resulted in linear reductions (P < 0.01) in DM, OM, CP, TCH and metabolizable energy (ME) intake, and a linear increase (P < 0.01) in NDF ingestion. Tropic semi-arid hair lambs had higher DM, OM, NDF, CP, and TCH intake than temperate wool lambs. Although there were no genotype effects in OM and GE coefficient of digestibility, hair lambs showed more efficient (P < 0.05) digestibility of DM, CP, NDF and TCH. Increases in forage levels of diets corresponded to a negative linear effect (P < 0.01) in the apparent digestibility of DM, OM, CP, TCH and GE, while apparent digestibility of NDF increased linearly (P < 0.01). Total endogenous nitrogen (fecal plus urinary N) for F(1) Ideal x Ilede France wool and Santa Ines hair lambs were, respectively, 182 and 312 mg/kg(0.75) per day. Thus, Santa Ines tropic semi-arid hair lambs showed to be more responsive than F(1) Ideal x Ile de France temperate wool lambs to low quality fibrous diets. (C) 2004 Elsevier B.V. All rights reserved.

Evaluation of in vitro gas production of roughages and their mixtures using the curves subtraction method

The in vitro gas production of four single roughages and their paired combinations (1:1 on dry matter basis) were evaluated. Two roughage samples (100 mg) per treatment were fermented with ruminal fluid during a 48 h incubation period. Total 48 h gas volumes of fermentation dry matter (DM), neutral detergent fiber (NDF) and soluble compounds in neutral detergent (NDS) were for sugarcane = 16.8, 11.2, 6.9 mL; sugarcane + corn silage = 20.1, 12.6, 9.1 mL; sugarcane + 60-day elephantgrass = 16.5, 17.6 mL; sugarcane + 180-day elephantgrass = 13.8, 8.2, 5.9 mL; corn silage = 18.8, 16.8, 4.7 mL; corn silage + 60-day elephantgrass = 16.3, 15.4, 2.4 mL; corn silage + 180-day elephantgrass = 16.1, 11.8, 4.2 mL; 60-day elephantgrass = 16.9, 19.0 mL and 180-day elephantgrass = fermented 10.7, 12.2 mL, respectively. The NDS gas production was not possible to estimate for sugarcane + 60-day elephantgrass, 60-day elephantgrass and 180-day elephantgrass. The present data shows that the curves subtraction method can be an option to evaluate the contribution of the soluble fractions in roughages to digestion kinetics. However, this method underestimates the NDS gas contribution when roughages are low in crude protein and soluble carbohydrates. It is advisable to directly apply the two-compartmental mathematical model to the digestion curves for roughage DM, when determining the NDS gas volume and the digestion rate. This method is more straightforward and accurate when compared to the curve subtraction method. Non-structural carbohydrates combined with fiber and protein promoted a positive associative effect in sugarcane + corn silage (50:50) mixture. Therefore, it can be concluded that the soluble fraction of roughages greatly contributes to gas production. (C) 2004 Elsevier B.V. All rights reserved.

Degradação ruminal de silagem de capim-elefante com adição de vagem de algaroba triturada

This research was carried out to evaluate the ruminal degradation of dry matter (DM), crude protein (CP) and neutral detergent fiber (NDF) of silages of elephant grass (Pennisetum purpureum) cutting in 70; 90 and 110 days after regrowth with inclusion of 0; 5; 10 and 15% of mesquite (Prosopis juliflora) meal, based on natural matter in a completely randomized design, in split plot arrangement. Samples of silages were incubated in the rumen of two Jersey cows for 3; 6; 12; 24; 48; 72 and 96 h, and the bags at time "zero" were only washed with water to determine the soluble fraction. There was not interaction (P> 0.05) incubation time x inclusion of mesquite pods x cutting age of the grass for DM degradability, there was only interaction (P <0.05) between these factors for CP and NDF degradability. The most effective DM degradability (42.54%) was observed for 15% inclusion of mesquite pods. The effective CP degradability was higher (69.04%) for elephant grass silage with 70 days after regrowth with 15% of mesquite pods. The inclusion of mesquite pods in elephant grass silages improve DM, CP and NDF degradability, while increment of the age after regrowth result in reduction of this parameters.

Determinação bromatológica de Pleurotus ostreatus cultivado em resíduos de diferentes cultivares de bananeira

The objective of this work was to evaluate the nutritional composition (raw protein, ether extract, raw fiber, FDA, FDN and ash) of the POS 09/100 strain of Pleurotus ostreatus grown in three combinations of residues (pseudo-stem, leave and pseudo-stem + leaf) and four banana tree cultivars (Thap maeo, Prata ana, Pelipita and Caipira). The basidiomata harvested were submitted to dehydration in a forced ventilation stove with temperature adjusted to 40 degrees C until reaching constant weight, being then grinded in a knife mill. The method proposed by Kjeldahl (1883) was used to determine total nitrogen. The Weende method (AOAC, 1997) was employed to determine crude fiber, acid-detergent fiber (ADF) and neutral detergent fiber (NDF). According to the results obtained, crude protein, ash, ADF and NDF contents varied with the kind of residue and banana tree cultivar; the substrate prepared with leaves of banana tree (Prata Ana cultivar) yielded the highest crude protein (35.4%) and ash (6.7%) contents in the basidiomata of P. streams; the substrate prepared with pseudo-stein of banana tree (Prata Ana cultivar) provided the highest ADF (31.6%) and NDF (41.9%) contents in the basidiomata of P. ostreatus. Ether extract and crude fiber contents of P. ostreatus didn't vary in function of the treatments, with averages of 2.45 and 11.27%, respectively.

Productive and reproductive performance of heifers fed different levels of urea in the diet

The objective of the present study was to evaluate the nutrient intake, blood parameters, follicular diameter and performance of pre-puberty crossbred heifers fed isoproteic diets (14.1%CP) containing 0.0; 0.44; 0.88 and 1.32% urea on the total dry matter (DM) of the diet, with a 77:23 roughage:concentrate ratio. Twenty-four 18- month old heifers (Holstein x Zebu), 277.9 kg mean live weight (LW) were used, distributed in four treatments and six replications in a randomized complete design. The following were evaluated: dry matter intake (DM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), ether extract (EE), hemicellulose (HEM), plasmatic ureic nitrogen (PUN), plasmatic glucose, plasmatic total cholesterol, follicular diameter and daily weight gain (DWG). No influence of the urea levels in the diet was observed on NDF and HEM intake. A maximum intake was obtained of DM (8.75 kg day(-1)), CP (0.88 kg day(-1)), ADF (2.5 kg day(-1)) and EE (0.17 kg day(-1)) respectively for the levels 0.7, 0.8, 0.7 and 0.7% urea in total DM. The 0.6%; 0.77% and 0.6% urea levels in diet were the critical points for obtaining maximum response for the PUN (10.96 mg dL(-1)) and plasmatic glucose (84.97 mg dL(-1)) concentrations and, for follicular diameter (11.08 mm) on the 40(th); 24(th) and 31(st) day, respectively. The plasmatic total cholesterol concentration and DWG were not influenced by the urea added to the diet, with averages of 119.39 mg dL(-1) and 1.66 kg day(-1), respectively. It was concluded that urea can be added up to 1.32% on the total DM of the diet for pre-puberty crossbred heifers.

Degradabilidade ruminai da fibra em detergente neutro e do nitrogênio insolúvel em detergente neutro da silagem de milho e do farelo de soja, em bovinos da raça nelore

The nylon bag in situ degradation thecnique was employed to study the ruminai degradability of the neutral detergent fiber and neutral detergent insoluble nitrogen of the corn silage and soybean meal in four rumen fistulated Nellore steers, averaging 36 months of age and 520 kg of liveweight. A randomized completelcs block experimental design was used, where the animals constituted the blocks. It was used diets with two levels of concentrate: 20 and 40%.The forage used in the diets was corn silage, and the concentrate ingredients were: soybean meal, cottonseed meal, corn grain and sorghum grain. The NIDN degradation rate of the corn silage and the soybean meal showed a decrease of 32,1% and of 46,0 % as a function of the higher concentrate level of the diet, but the effective and potential degradability of this fraction were not affected. Concerning to the NDF, the soluble fraction, potentially degradable and undegrable , were not affected by the increase on the diet concentrate level, but for the corn silage, there were 21,8% of reduction on the effective degradability of NDF. The use of lag time promoted higher degradability values for the studied fraction. The obtained values for some evaluated parameters, different from that assumed by CNCPS, showed the necessity of more data about brazilian used feeds, for model adjustments.

Efeito do Tratamento com Hidróxido de Sódio sobre a Fração Fibrosa, Digestibilidade e Tanino do Feno de Jurema-Preta (Mimosa tenuiflora. Wild)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Disponibilidade, composição bromatológica e consumo de matéria seca em pastagem consorciada de Brachiaria decumbens com Stylosanthes guianensis

The objective of this work was to evaluate the herbage availability, nutritive value, dry matter intake and grass and legume percentage in diet of crossbred Holstein-Zebu cows, in pasture with Brachiaria decumbens cv. Basilisk, Stylosanthes guianensis var. vulgaris cv. Mineirão and tree legumes. To estimate the fecal output, it was used 10 g cow -1 day -1 of chromium oxide during ten consecutive days. Extrusa samples were used to determine the chemical composition and in vitro dry matter digestibility. B. decumbens availability varied with climatic conditions, while S. guianensis availability decreased linearly along the experimental period. Dry matter intake was higher in May/2001 (1.9% body weight) and did not differ among other months (1.5% body weight). Low dry matter intake values were related to low in vitro dry matter digestibility coefficients (42.1 % to 48.0%) and high neutral detergent fiber content (70.2% to 79.4%). Dry matter intake was directly related to legume percentage in the pasture. This observation could indicate the potential of mixed pasture for improving nutritive value in dairy cattle diet.

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

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Composição e digestibilidade in vitro de genótipos de capim-elefante, aos 56 dias de rebrota

Twelve elephant grass genotypes were evaluated in a randomized blocks design with three repetitions. The experimental parcel was of 4 lines with 3m of length, spaced of 1 m and fertilized with 100 kg of P2O5, 100 kg of N, 60 kg of K2O and 25 kg of micronutrients/ha. Significant differences were observed among the genotypes for neutral detergent fiber (FND), acid detergent fiber (FAD) and lignin. The genotypes CNPGL 92-70-02, CNPGL 91-25-01 and CNPGL 93-32-02 showed low values for FND, FAD and lignin, simultaneously, outstanding between the others. There were no significant differences in the levels of dry matter and crude protein contents and in in vitro dry matter digestibility between the genotypes.