Nutritive value and physical characteristics of Xaraes palisadegrass as affected by grazing strategy

The aim of this study was to ascertain whether the defoliation frequency based on a fixed rest period would generate variable sward structural and physiological conditions at each subsequent grazing event. The relative importance of the physiological age was established in comparison with the chronological age in the determination of the forage nutritive value of Xaraes palisadegrass [Brachiaria brizantha (Hochst ex A. RICH.) STAPF. cv. Xaraes]. Two grazing frequencies were defined by light interception (LI) at initiation of grazing (95% LI - ""target grazing"" [TG] or 100% LI - ""delayed grazing"" [DG]) and one based on chronological time, grazing every 28 days (28-d). Forage produced under the TG schedule was mostly leaves (93%) with a higher concentration of crude protein (CP; 138 g/kg in the whole forage), a lower concentrations of neutral detergent fibre (NDF) in the stems (740 g/kg), and higher in vitro dry matter digestibility (IVDMD) of the leaves (690 g/kg), compared to the other treatments. Lower grazing frequency strategies (DG and 28-d) resulted in forage with higher proportions of stems (10 and 9%, respectively). Strategies based on light interception did not produce pre-graze forage with a uniform nutritive value, as the indicators varied across grazing cycles. The treatment based on fixed days of rest did not result in uniformity.

Influence of thermoplastic extrusion on the nutritive value of bovine rumen protein

This Study investigated the impact of thermoplastic extrusion on the nutritive quality of bovine rumen protein. Proximal composition, amino acid profile and in vivo true protein digestibility among rats were determined in raw (RBR) and extruded (EBR) rumen. Raw and extruded bovine rumen presented high percentages of protein (more than 95% on dry basis). Neither raw nor extruded proteins had any limiting amino acid, and the RBR and EBR amino acid scores were, respectively, 1.28 (leucine) and 1.25 (methionine plus cystine). Extrusion reduced significantly true protein digestibility from 97.7% to 93.1% (p < 0.001), but protein digestibility-corrected amino acid scores for both proteins (RBR and EBR) were 100%. Animal growth presented comparable profiles using raw and extruded rumen. In conclusion, thermoplastic extrusion did not affect the protein quality of bovine rumen, and this does not hinder the use of this material as a food ingredient. (C) 2009 Elsevier Ltd. Ail rights reserved.

Nutritional characteristics and in vitro digestibility of silages from different corn cultivars harvested at two cutting heights

The objective of this study was to evaluate the nutritional traits and in vitro digestibility of silages from different corn cultivars harvested at two cutting heights. It was evaluated 11 cultivars (Dina 766, Dina 657, Dina 1000, P 3021, P 3041, C 805, C 333, AG 5011, FO 01, Dina co 9621 and BR 205) harvest 5 cm above ground (low) and 5 cm below the intersection of the first ear (high). It was used a random block design (three blocks), arranged in a 11 × 2 factorial scheme. Silages from plants harvested at high cutting height presented average content of dry matter significantly superior to silages from plants harvested at low height. Cultivars FO 01, AG 5011, Dina co 9621 and Dina 766 presented greater content of crude protein than cultivars C 805, P 3041 and P 3021, which presented the lowest contents of this nutrient. The raise in the cut height increased in vitro dry matter true digestibility coefficients and in vitro dry matter digestibility of silage evaluated. The increase in cut height improved nutritive value of silages by decreasing concentrations of fibrous fractions and increasing in vitro dry matter digestibility.

Efeitos do teor de carboidratos solúveis sobre as características da silagem de cana-de-açúcar

Objetivou-se quantificar na cana-de-açúcar o teor de carboidratos solúveis (CHOs) que anula a produção de etanol e avaliar os efeitos desses carboidratos sobre o valor nutritivo e outras características fermentativas da silagem de cana-de-açúcar. Utilizou-se o delineamento inteiramente casualizado com três tratamentos, cada um com quatro repetições. Os tratamentos consistiram da retirada total do caldo da cana-de-açúcar, por meio de prensagem, e de sua reconstituição (0, 50 ou 100%) à cana. No nível de 50% de reconstituição, o caldo foi adicionado à cana juntamente com 50% de água e, no nível 0%, adicionou-se 100% de água à cana. A restituição resultou em concentrações de 41,6; 34,0 e 23,0% de carboidratos solúveis na matéria seca (MS). O material foi ensilado em 12 silos experimentais confeccionados a partir de baldes plásticos. A abertura dos silos foi realizada 85 dias após a ensilagem, quando foram determinados os teores dos ácidos orgânicos e a composição química das silagens. A retirada de carboidratos solúveis da cana-de-açúcar teve efeito linear decrescente sobre os teores de matéria seca, o teor de carboidratos solúveis e a digestibilidade in vitro da matéria seca (DIVMS) das silagens, no entanto, ocasionou aumento dos teores de fibra detergente ácido (FDA), fibra detergente neutro (FDN) e lignina. Observou-se efeito linear decrescente da retirada dos carboidratos solúveis sobre os teores de etanol e ácidos lático e butírico e as perdas de matéria seca das silagens. Não se observaram efeitos de tratamentos sobre os dados de estabilidade aeróbia. A produção de etanol seria nula se a cana-de-açúcar contivesse apenas 12,4% de CHOs com base na matéria seca (MS).

Production of Cellulolytic Enzymes by Anaerobic Fungi Cultivated in Different Conditions

The present paper studies the influence of different nutrients for the production of two cellulolytic enzymes: endo beta-1.4 glucanase and exo beta-1.4 glucanase by anaerobic fungi taken from cow rumen, that were fed a diet of corn silage and Brachiaria decumbens grass hay. During the enzymatic degradation assays, it was observed that the addition of some essential nutrients in the formulation of the culture medium contributed positively in the cellulolytic enzyme production, with exception of riboflavin. Such results contributed in the establishment of an effective method for the evaluation of enzymatic activities in anaerobic fibrolytic fungi. In this work, nutrients added to enrich the culture medium have successfully proven that they can be used as inoculating agents (inductors) in diets rich in ensilage with law nutritive value.

Chemical characterization and oxidative stability of the oils from three morphotypes of Mauritia flexuosa L.f, from the Peruvian Amazon

Three morphotypes of aguaje Mauritia flexuosa were tested, classified by the color of their mesocarpium: ""color"", ""shambo"" and ""amarillo"", collected from different areas near the city of Iquitos, Peru. Also, physical-chemical analyses of the mesocarpium were performed, such as the characterization of fatty acids by gas chromatography, determination of beta- carotene y alpha tocopherol by high efficiency liquid chromatography system in normal and reverse phase and the determination of oxidation induction time in the Rancimat apparatus. Proximate, mineral and fatty acid analyses were done on the seeds. The aguaje mesocarpium is rich in oleic oil (""amarillo"": 75.63% +/- 0.31), (beta-carotene (""amarillo"": 342.42ug/g 0.71) and alpha- tocopherol (""color"": 685.81mg/L +/- 1.04), plus the morphotype ""color"" has a superior oxidation induction time compared to other morphotypes with 6.91 +/- 0.01. The aguaje seed contains significant amounts of (06 (linoleic oil) in ""shambo"" with 36.04 +/- 0.09%. The results indicate that these oils, regardless their classification, contain important chemical compounds that give them a special nutritive value.

A new approach for in vitro bioassay to measure tannin biological effects based on a gas production technique

The aim of this paper was to study a method based on gas production technique to measure the biological effects of tannins on rumen fermentation. Six feeds were used as fermentation substrates in a semi-automated gas method: feed A - aroeira (Astronium urundeuva); feed B - jurema preta (Mimosa hostilis), feed C - sorghum grains (Sorghum bicolor); feed D - Tifton-85 (Cynodon sp.); and two others prepared mixing 450 g sorghum leaves, 450 g concentrate (maize and soybean meal) and 100 g either of acacia (Acacia mearnsii) tannin extract (feed E) or quebracho (Schinopsis lorentzii) tannin extract (feed F) per kg (w:w). Three assays were carried out to standardize the bioassay for tannins. The first assay compared two binding agents (polyethylene glycol - PEG - and polyvinyl polypirrolidone - PVPP) to attenuate the tannin effects. The complex formed by PEG and tannins showed to be more stable than PVPP and tannins. Then, in the second assay, PEG was used as binding agent, and this assay was done to evaluate levels of PEG (0, 500, 750, 1000 and 1250 mg/g DM) to minimize the tannin effect. All the tested levels of PEG produced a response to evaluate tannin effects but the best response was for dose of 1000 mg/g DM. Using this dose of PEG, the final assay was carried out to test three compounds (tannic acid, quebracho extract and acacia extract) to establish a curve of biological equivalent effect of tannins. For this, five levels of each compound were added to I g of a standard feed (Lucerne hay). The equivalent effect showed not to be directly related to the chemical analysis for tannins. It was shown that different sources of tannins had different activities or reactivities. The curves of biological equivalence can provide information about tannin reactivity and its use seems to be important as an additional factor for chemical analysis. (C) 2007 Elsevier B.V. All rights reserved.

Effects of aeration on characteristics of sugarcane silage.

Effects of aeration on characteristics of sugarcane silage. This trial aimed at evaluating, the deleterious effects of aeration time on nutritive value and other fermentative characteristics of sugarcane silage. A completely randomized design was used with three treatments and four repetitions per treatment. Fresh chopped sugarcane was exposed to aeration for 0, 4 or 8 hours, and ensiled soon After exposure, the material was ensiled in 12 laboratory silos (plastic buckets). Silos were opened 85 after ensiling, when organic acids contents and chemical composition of silages were determined. Deviation of linearity (p < 0.05) was observed for aeration time on dry matter. A positive linear effect was observed (p < 0.05) on ADF, NDF and soluble carbohydrates content, but negative for ammoniacal nitrogen content and in vitro digestibility of dry matter. For organic acids content, deviation of linearity was observed on acetic acid, with the lowest content (1.5% of DM) observed after 8 hours of aeration, and a negative linear effect was observed for lactic and butyric acids, as well as for pH values. There were no effects on ethanol concentration, which remained very high (22% of DM), regardless of aeration time. Aerobic stability of silage worsened with the increase in aeration time.

Breastfeeding and non-nutritive sucking patterns related to the prevalence of anterior open bite in primary dentition

OBJECTIVE: Nutritional, immunological and psychological benefts of exclusive breastfeeding for the frst 6 months of life are unequivocally recognized. However, mothers should also be aware of the importance of breastfeeding for promoting adequate oral development. This study evaluated the association between breastfeeding and non-nutritive sucking patterns and the prevalence of anterior open bite in primary dentition. MATERIAL AND METHODS: Infant feeding and non-nutritive sucking were investigated in a 3-6 year-old sample of 1,377 children, from São Paulo city, Brazil. Children were grouped according to breastfeeding duration: G1 - non-breastfed, G2 - shorter than 6 months, G3 - interruption between 6 and 12 months, and G4 - longer than 12 months. Three calibrated dentists performed clinical examinations and classifed overbite into 3 categories: normal, anterior open bite and deep bite. Chi-square tests (p<0.05) with odds ratio (OR) calculation were used for intergroup comparisons. The impact of breastfeeding and non-nutritive sucking on the prevalence of anterior open bite was analyzed using binary logistic regression. RESULTS: The prevalence estimates of anterior open bite were: 31.9% (G1), 26.1% (G2), 22.1% (G3), and 6.2% (G4). G1 would have signifcantly more chances of having anterior open bite compared with G4; in the total sample (OR=7.1) and in the subgroup without history of non-nutritive sucking (OR=9.3). Prolonging breastfeeding for 12 months was associated with a 3.7 times lower chance of having anterior open bite. In each year of persistence with non-nutritive sucking habits, the chance of developing this malocclusion increased in 2.38 times. CONCLUSIONS: Breastfeeding and non-nutritive sucking durations demonstrated opposite effects on the prediction of anterior open bite. Non-breastfed children presented signifcantly greater chances of having anterior open bite compared with those who were breastfed for periods longer than 12 months, demonstrating the benefcial infuence of breastfeeding on dental occlusion.

Forced convection to laminar flow of liquid egg yolk in circular and annular ducts

The steady-state heat transfer in laminar flow of liquid egg yolk - an important pseudoplastic fluid food - in circular and concentric annular ducts was experimentally investigated. The average convection heat transfer coefficients, determined by measuring temperatures before and after heating sections with constant temperatures at the tube wall, were used to obtain simple new empirical expressions to estimate the Nusselt numbers for fully established flows at the thermal entrance of the considered geometries. The comparisons with existing correlations for Newtonian and non-Newtonian fluids resulted in excellent agreement. The main contribution of this work is to supply practical and easily applicable correlations, which are, especially for the case of annulus, rather scarce and extensively required in the design of heat transfer operations dealing with similar shear-thinning products. In addition, the experimental results may support existing theoretical analyses.

Repetibilidade da mensuração de imagens das características de carcaça obtidas por ultrassonografia em fêmeas Nelore

Avaliou-se a repetibilidade da mensuração de imagens de ultrassom da área do músculo longissimus dorsi (AOL) e das espessuras de gordura subcutânea do lombo (EGL) e da garupa (EGG). Imagens de ultrassom tomadas no lombo (entre a 12ª e a 13ª costela) e na garupa (entre os músculos gluteus medium e biceps femoris) de novilhas Nelore de 14 a 22 meses de idade foram classificadas em aceitáveis, marginais e rejeitáveis. As imagens aceitáveis e marginais foram mensuradas duas vezes por três técnicos em diferentes níveis de treinamento. Foram estimadas as repetibilidades entre e dentro de técnicos por classe de qualidade da imagem, para determinação do efeito da qualidade da imagem e do técnico no valor absoluto da diferença entre a primeira e a segunda mensuração dessas características. A repetibilidade para as imagens aceitáveis foi maior que para imagens marginais, tanto entre como dentro de técnicos. Na análise da diferença absoluta entre a primeira e a segunda interpretação, foram significativos os efeitos de técnico para AOL e EGL e de classe de qualidade da imagem para AOL. Em geral, o técnico com maior experiência apresentou maiores valores de repetibilidade. É recomendável que a mensuração de imagens de animais de mesmo grupo contemporâneo seja feita por um único técnico.

Adding value to the meat of spent laying hens manufacturing sausages with a healthy appeal

The aim of this study was to evaluate the viability of the use of spent laying hens' meat in the manufacturing of mortadella-type sausages with healthy appeal by using vegetable oil instead of animal fat. 120 Hy-line® layer hens were distributed in a completely randomized design into two treatments of six replicates with ten birds each. The treatments were birds from light Hy-line® W36 and semi-heavy Hy-line® Brown lines. Cold carcass, wing, breast and leg fillets yields were determined. Dry matter, protein, and lipid contents were determined in breast and leg fillets. The breast and legg fillets of three replicates per treatment were used to manufacture mortadella. After processing, sausages were evaluated for proximal composition, objective color, microbiological parameters, fatty acid profile and sensory acceptance. The meat of light and semi-heavy spent hens presented good yield and composition, allowing it to be used as raw material for the manufacture of processed products. Mortadellas were safe from microbiological point of view, and those made with semi-heavy hens fillets were redder and better accepted by consumers. Values for all sensory attributes were evaluated over score 5 (neither liked nor disliked). Both products presented high polyunsaturated fatty acid contents and good polyunsaturated to saturated fatty acid ratio. The excellent potential for the use of meat from spent layer hens of both varieties in the manufacturing of healthier mortadella-type sausage was demonstrated.

Lysine and zinc chelate in diets for brown laying hens: effects on egg production and composition

It was evaluated the effects of levels of digestible lysine and chelate zinc combined in the diet for laying on the egg quality. It was used 720 birds, from 48 to 60 weeks of age, distributed in a completely randomized design in a 3 × 5 factorial scheme with three levels of zinc and five levels of lysine, applied into six replicates in the experimental units of eight birds per plot. The levels were: 137, 309 and 655 ppm zinc and 0.482, 0.527, 0.582, 0.644 and 0.732% digestible lysine. It was not observed any interaction among digestible lysine and zinc for the primary variables of fractions and egg composition. Levels of zinc reduced egg weight, suggesting the lowest efficiency in nutrient intake. At the highest dietary concentration of zinc, the addition of digestible lysine coincided with a linear increase in shell weight. However, zinc addition, regardless of lysine level in the diet, resulted in the reduction of egg weight and of the percentage of mineral matter in the yolk, limiting the efficiency of mineral deposition in this fraction of the egg. Concentration of zinc that produced the best results was 137 ppm inasmuch as higher quantities limit the use of digestible lysine, with effects harming composition and egg quality. The study indicates the following requirement for digestible lysine: 0.639% from the 48th to the 52nd week, 0.679% from the 52nd to 56th week, and 0.635% from the 56th to the 60th week. Considering the total period from 48th to the 60th week, the level 0.638% of lysine or the daily intake of 707 mg of the amino acid met the requirement for egg quality of semi-heavy layers used in this study.

Níveis de lisina digestível e zinco quelato sobre os parâmetros produtivos de poedeiras marrons

Objetivou-se avaliar a produção de ovos em galinhas Isa Brown alimentadas com dietas com diferentes níveis de lisina digestível e zinco quelato. Utilizaram-se 720 poedeiras marrons, em dois períodos de avaliação, de 24 a 36 e de 48 a 60 semanas de idade. As dietas foram avaliadas em delineamento inteiramente casualizado, em esquema fatorial 5 × 3, composto de 5 níveis de lisina digestível (0,482; 0,527; 0,582; 0,644 e 0,732%) e 3 de zinco quelato (20, 40 e 80 ppm), de modo que cada combinação foi testada em 6 repetições de 8 aves por unidade experimental. Na fase de 24 a 36 semanas de idade, houve influência da interação de lisina digestível e zinco no consumo médio diário de ração e na porcentagem de postura. Na fase de 48 a 60 semanas, a interação foi evidenciada somente no consumo médio diário de ração. O aumento da concentração de lisina digestível favoreceu o consumo de ração em todos os níveis de zinco. Em ambas as fases, a menor concentração de zinco atende às necessidades de produção das aves. O valor médio estimado de lisina digestível ideal foi de 0,732% para a fase de 24 a 36 semanas e de 0,578% para a fase de 48 a 60 semanas de idade.

Combining Legendre's Polynomials and Genetic Algorithm in the Solution of Nonlinear Initial-Value Problems

This work develops a method for solving ordinary differential equations, that is, initial-value problems, with solutions approximated by using Legendre's polynomials. An iterative procedure for the adjustment of the polynomial coefficients is developed, based on the genetic algorithm. This procedure is applied to several examples providing comparisons between its results and the best polynomial fitting when numerical solutions by the traditional Runge-Kutta or Adams methods are available. The resulting algorithm provides reliable solutions even if the numerical solutions are not available, that is, when the mass matrix is singular or the equation produces unstable running processes.