Produção de matéria seca e proteína bruta e relação folha/colmo de genótipos de capim-elefante aos 56 dias de rebrota

Doze genótipos de capim-elefante foram avaliados em um delineamento em blocos ao acaso com três repetições. A parcela experimental foi composta de quatro linhas com 3 m de comprimento, espaçadas a 1 m e adubadas com 100 kg de P2O5, 100 kg de N, 60 kg de K2O e 25 kg de micronutrientes/ha. Os genótipos diferiram significativamente quanto à altura da planta e à produção de MS, de PB e matéria seca digestível (MSD)/ha. Os genótipos CNPGL 92-94-01, CNPGL 92-79-02, CNPGL 91-06-02, CNPGL 94-07-02, CNPGL 94-09-01, BAG 66, CNPGL 93-32-02 e cv. Cameroon apresentaram os maiores rendimentos de MS, PB e MSD e não diferiram significativamente quanto à relação folha/colmo (F/C). A análise de Cluster sugeriu o agrupamento dos genótipos de maior produção de MS, PB e MSD e dos genótipos com menores produções de MS, PB e MSD.

Trânsito gastrintestinal e digestibilidade aparente de nutrientes em eqüinos alimentados com dietas contendo grãos secos ou silagem de grãos úmidos de triticale

Cinco éguas mestiças (idade e peso corporal médios de seis anos e 480 kg PV) foram distribuídas em delineamento experimental em quadrado latino para se e avaliar a utilização de dietas contendo grãos de triticale (secos ou ensilados) em substituição ao milho na alimentação de eqüinos, por meio do ensaio de avaliação do trânsito gastrintestinal e da digestibilidade. Os tratamentos consistiram de três níveis de grãos de triticale em substituição aos grãos de milho (0, 50 e 100%) e duas formas de conservação dos grãos de triticale (secos ou ensilados). As dietas foram isoprotéicas (12,5% PB), com ingestão diária de MS pelos animais de 2,0% PV (relação volumoso : concentrado de 50:50). Os coeficientes de digestibilidade aparente (CDa) da MS, MO, PB e FDN foram determinados indiretamente. Os parâmetros de trânsito gastrintestinal avaliados foram: k1 (taxa de passagem pelo intestino grosso), k2 (taxa de passagem pelo estômago), TT (tempo de trânsito), TMR (tempo médio de retenção) e TMRT (tempo médio de retenção total). Não houve diferença para os CDa da MS, MO, PB e FDN entre as dietas experimentais, observando-se valores médios de 64,31; 65,14; 74,13 e 57,25%, respectivamente. Considerando-se a cinética das fases sólida e líquida, notou-se efeito somente para k2 na fase sólida da digesta, cujo valor nas rações contendo 100% de triticale (seco ou ensilado) foi de 19,63%/h e na dieta controle (0% de triticale), de 23,72%/h. Observou-se efeito linear crescente para o TT na fase sólida da digesta, com a elevação dos níveis de substituição dos grãos de milho pelos grãos de triticale ensilados. Concluiu-se que os concentrados para eqüinos podem ser formulados com grãos de triticale secos ou ensilados em substituição total ao milho. A inclusão de grãos de triticale na alimentação desta espécie animal promoveu trânsito lento da fase sólida da digesta.

Valor nutritivo e estudo cinético do trato digestivo de dietas contendo grãos secos ou ensilados de sorgo de baixo e alto tanino para eqüinos

Quatro éguas sem raça definida (idade e peso corporal médios de seis anos e 400 kg) foram distribuídas em delineamento experimental em quadrado latino para se avaliar o valor nutritivo e o estudo cinético do trato digestivo de grãos secos ou ensilados de sorgo de baixo e alto conteúdos de tanino na alimentação de eqüinos. Os tratamentos consistiram de dietas contendo dois híbridos de grãos de sorgo (baixo e alto níveis de tanino) e dois métodos de conservação (secos e ensilados). As dietas foram isoprotéicas (12,4% PB), com ingestão diária de MS estabelecida em 1,5% PV (relação feno:concentrado de 50: 50). Os parâmetros de trânsito gastrintestinal avaliados foram: k1 (taxa de passagem pelo intestino grosso), k2 (taxa de passagem pelo estômago), TT (tempo de trânsito), TMR (tempo médio de retenção) e TMRT (tempo médio de retenção total). Os tratamentos não afetaram os coeficientes de digestibilidade aparente (CDa) da MS e do amido, cujos valores médios foram 54,04 e 98,91%, respectivamente. Verificou-se efeito benéfico da ensilagem dos grãos de sorgo de alto conteúdo de tanino sobre a digestibilidade da PB e FDN. A CDa da PB e FDN para a dieta contendo grãos secos de sorgo de alto teor de tanino foi de 49,76 e 32,20% e para as dietas com grãos de sorgo de baixo conteúdo de tanino (seco ou ensilado) e grãos ensilados de sorgo de alto teor de tanino foi de 65,63 e 43,32%, respectivamente. Obteve-se somente efeito do método de conservação dos grãos de sorgo (secos vs ensilados) sobre o TMR, em que o valor para as dietas com silagens de grãos ensilados e secos foi, respectivamente, de 40,08 e 37,9h. Concluiu-se que os grãos de sorgo secos de alto teor de tanino não devem ser usados como principal grão energético nos concentrados para eqüinos, por diminuírem a digestibilidade da proteína e fibra.

Efeitos da frequência de fornecimento do volumoso e concentrado no comportamento ingestivo de vacas e novilhas em confinamento

Este estudo foi conduzido com o objetivo de avaliar a influência da frequência no fornecimento de volumoso e concentrado e/ou da categoria animal sobre o comportamento ingestivo de bovinos. Foram utilizadas 16 novilhas e 16 vacas com idade média inicial de 20 e 66 meses e peso médio inicial de 338 e 432 kg, respectivamente. Os tratamentos foram representados pelas frequências de fornecimento do volumoso e do concentrado: 2 V/C - volumoso e concentrado duas vezes ao dia; 1 V/C - volumoso e concentrado uma vez ao dia; 1 V/2 C - volumoso uma vez ao dia e concentrado duas vezes ao dia; 1 V/3 C - volumoso uma vez ao dia e concentrado três vezes ao dia, ofertadas às categorias vacas e novilhas. A dieta foi composta de 60% de silagem de milho e 40% de concentrado com base na matéria seca (MS). O delineamento experimental foi inteiramente casualizado em arranjo fatorial 4 × 2 (frequências × categorias). Os dados foram submetidos à análise de variância e as médias, comparadas pelo teste t. A interação frequência de fornecimento e categoria animal foi significativa para as características tempo de ruminação e ócio, eficiência de ruminação da matéria seca e da fibra detergente neutro, número de bolos diário e tempo diário de mastigação. em relação às vacas, as novilhas apresentaram maiores tempos de ócio e mastigação quando receberam a alimentação uma vez ao dia. A frequência de fornecimento da dieta não influenciou o tempo de consumo. As vacas apresentaram maior tempo consumindo alimento e taxa de ingestão em comparação às novilhas (4,38 vs 4,09 horas e 2,91 vs 2,35 kg de MS/hora de consumo, respectivamente). O aumento na frequência da alimentação estimula os animais a maior ingestão de alimento no momento do fornecimento.

Hydroxymethylnitrofurazone:Dimethyl-beta-cyclodextrin Inclusion Complex: A Physical-Chemistry Characterization

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

Digestão total e pré-cecal dos nutrientes em potros fistulados no íleo

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Efeitos da amonização sobre a ocorrência de fungos, composição química e digestibilidade in vitro de fenos de grama Seda (Cynodon dactylon (L.) Pers.)

The experiment was conducted with grama seda (Cynodon dactylon (L.) Pers.) hays stored with a low moisture content (12-15%) and without chemical treatment, and hays stored with a high moisture content (20-25%) and treated with anhydrous ammonia (NH3) al 0.5 and 1.0% of DM, and urea at 0.9 and 1.8% of DM. At 65 days after treatment (AT) under a plastic cover, the bales were opened and samples were taken at 3, 15 and 30 days to determine the chemical composition and in vitro digestibility (IVDMD) of the hays. For the identification of fungi, samples were taken at 0, 15 and 30 days AT. The data were analyzed according to a split-plot design with the effects of the chemical treatments studied in the main plot and the effects of the periods of post-treatment studied in the sub-plots, Fourteen genera of fungi were observed in the hays, not treated and treated with NH3 and urea, with a higher occurrence of Cladosporium, Curvularia, Aspergillus, and Penicillium. Treatment with anhydrous ammonia and 1.8% urea controlled the occurrence of Aspergillus; however, Penicillium decreased in hays treated with ammonia 30 days AT. Ammoniation did not influence the contents of ADF, cellulose and lignin in the hays, but NDF and hemicellulose decreased with the use of ammonia 30 days AT. The CP contents and the IVDMD increased with ammoniation. The CP contents decreased in hays treated with NH3 as days AT increase, while hays treated with urea did not change.

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.

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.

Avaliação das Sub-Frações dos Carboidratos e das Proteínas, Usando as Metodologias do Cncps e In situ com Bovinos da Raça Nelore. 2. Milho e Farelo de Algodão

The chemical composition of corn and cottonseed meal was determined in accordance with the Cornell Net Carbohydrate and Protein System (CNCPS) in diets with forage:concentrate ratios of 80:20 (D1) and 60:40(D2) using Nellore cattle. The potential and effective degradabilities of the carbohydrate and protein subfractions were also determined. For corn. diet 2 resulted in an increase for potentially degradable dry matter (DM). An increase was observed in the effective degradation of DM (EDDM) when lag time was not considered, however, the use of Eng time increased the EDDM for both diets, 23 and 18% for DI and D2. respectively. For cottonseed meal, diet 2 determined a reduction in the potentially degradable DM: therefore, the use of lag time increased the EDDM for bath diets, 14% for D1 and 15% for D2. The availability of corn starch (fraction B1) was lower than that determined by CNCPS. The higher values for the degradability of corn and cottonseed meal protein subfractions may indicate an underestimation by the model, and, or, could be attributed to the Zebu animals used in this study.

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.

Degradabilidade in situ do Capim Panicum maximum cv. Tanzânia Incubado Cortado ou na Forma de Extrusa

The aim of this study was to compare the chemical composition, in vitro dry matter disappearance (IVDMD) and ruminal degradation of Panicum maximum, J. cv. Tanzania samples obtained by clipping (square method) or extrusa collection (animal selection). In the in situ trial, three ruminal fistulated dry crossbred cows, with 499 kg LW, were used in a completely randomized block design with split-plot arrangement design. Five grams of clipped (+/- 2 cm) grass or extrusa samples were placed in nylon bags (7 x 14 cm) and rumen incubated during 3, 6, 12, 24, 48, 96 and 120 hours. The IVDMD and the CP, NDF and ADF content were, respectively, 55.8, 7.6, 81.9 e 43.6%, for the clipped grass and .66.5, 12.1, 78.8 e 39.5%, for the extrusa samples. The potential degradability of DM, C P, NDF and ADF were 62.59, 80.88, 50.73 and 46.65%, for clipped grass; and 79.53, 90.97, 71.21 and 65.68%, for extrusa samples. The quality of the selected animal diet (extrusa) was better than the available forage in terms of IVDMD and chemical composition (high protein and low fiber content). In situ degradability trials carried out with clipped samples, and non selected by animal, could not supply reliable results closed to the animal diet.

Alterações na produtividade e composição nutricional de uma pastagem após segundo ano de aplicação de diferentes doses de cama de frango

The objective was to evaluate the potential use of poultry litter, compared to mineral fertilization, productivity, features bromatologic and absorption of nutrients from a pasture of Brachiaria decumbens. The experimental area was installed in oxisoil in Uberlandia-MG. The design was randomized blocks with four replicates and the treatments used: control (without application of organic or mineral source), mineral fertilizer (60, 75 and 100 kg ha(-1), P K, respectively); organic fertilization with poultry litter at rates of 3,125, 6,250, 9,375 and 12,500 kg ha(-1). There were two cuts of the aerial part of Brachiaria decumbens, both at 60 days after treatment. We evaluated the yield of DM and the levels of CP, NDF, ADF, lignin, macro and micronutrients in shoots of grass. The results showed that application of poultry litter increased the productivity of DM and the levels of CP, N, P, K and Zn in Brachiaria decumbens. The poultry litter can be used as supplementary source of nutrients, the mineral fertilizer. The use of poultry litter not increased over the levels of S, Ca and Mg in Brachiaria decumbens.

Biodisponibilidade de fontes orgânicas e inorgânicas de zinco em ovinos

This research was done to compare the effects of different zinc sources and doses in the Santa Ines sheep diet. Forty lambs at weaning, with 18,4kg BW were randomly allotted and fed 10 treatments: 1- base diet without zinc supplementation; 2- base diet + 200mg Zn/kg of DM as zinc oxide; 3- base diet + 400mg Zn/kg of DM as zinc oxide; 4- base diet + 600mg Zn/kg of DM as zinc oxide; 5- base diet + 200mg Zn/kg of DM as amino acid zinc; 6- base diet + 400mg Zn/kg of DM as amino acid zinc; 7- base diet + 600mg Zn/kg of DM as amino acid zinc; 8- base diet + 200mg Zn/kg of DM as proteinato zinc; 9- base diet + 400mg Zn/kg of DM as proteinato zinc; 10- base diet + 600mg Zn/kg of DM as proteinato zinc. The animals were weighed and sampled for blood zinc analysis, phosphatase alkaline analysis and immunoglobulins G and M analysis. At the end of the experiment liver samples were collected to study the zinc hepatic levels. There was no difference in phosphatase alkaline levels, hepatic zinc levels and weight gain (P>0,05) but differences (P<0,05) in plasmatic zinc levels and in IgG and IgM levels were observed. Based on liver tissue uptake, estimates of the zinc bioavailability, through the regression equations showed that the organic and inorganic sources of zinc did not differ.

Avaliação da silagem de grãos úmidos de milho

This work had the objective of evaluating the effects of different percentages of corn (Zea mays L.) cob on the quality of the silage of high-moisture corn grains. The following treatments were studied: percentages of corn cob in the silage (0, 5, 10, 15 and 20%); period of sampling after opening the silos (zero, two, four and six days). The factorial arrangement 5 × 4 was studied according to a completely randomized block design with three replications. The variables studied were not affected by the sampling period. The buffering capacity and the pH were not affected by the cob, while the percent soluble carbohydrates and amoniacal nitrogen increasing until 1.2 and 1.89 unit percent, respectively. Increasing the amount of corn cobs reduced the contents of DM (from 63.9% to 58.6%), CP (from 10.0% to 7.3%), EE (from 4.87% to 3.92%) and the values of DMIVD (from 90.5% to 79.1%) in the silages and increasing the contents of acid detergente fiber (ADF) (from 3.3% to 12.9%) and neutral detergente fiber (NDF) (from 15.16% to 26.1%). The values of brute energy (BE) were not affected (P>0.01) by the cob corn in the silage.