Increase In Energy Concentration Research Articles

Evaluation of the Energy Use of Pruning Dipteryx alata Trees

Pruning is equivalent to the removal of whole branches or parts, living or dead, of a plant, to promote balance in the development of the species, therefore, the generation of waste portrays an indispensable and ever-present consequence. The residues derived from pruning come from silvicultural treatments and evidently have great potential to be used in energy generation. Briquetting, in addition to its energy advantage and practicality, collaborates with the mitigation of environmental impacts from encouraging the use of renewable energies to reducing the emission of greenhouse gases, as they are strongly recommended for replacing fossil coal. The main objective of this work was to evaluate the possibility, related to quality and productivity, of the energy use of residual biomass from urban pruning of Dipteryx alata, focusing on the production of briquettes, thus encouraging further studies related to native species of the Cerrado and the use of renewable energy. The contents of volatile materials, ash and fixed carbon, higher calorific value, basic and energetic density were determined, and briquettes were produced in a laboratory briquetting machine. The quality of the briquettes was determined through physical-mechanical analyses: apparent density, durability, tensile strength by diametral compression and expansion. The energy density of the biomass had a considerable increase after briquetting, confirming the increase in energy concentration per unit volume in densified materials. Therefore, it was concluded that the use of urban pruning residues of Dipteryx alata proved to be suitable for making briquettes to produce renewable and sustainable energy.

Effect of frying fat substitution by vegetable oil and energy concentration on diets for productive performance of broilers

En la dieta de pollos de engorde se adicionan lípidos para mejorar su eficiencia productiva, generalmente grasa de fritura (GF), reciclada de restaurantes, por tener menor costo que el aceite vegetal (AV). El objetivo de este trabajo fue evaluar el efecto de la sustitución de GF por AV en dietas estándar (DEE) y dietas altas en energía (DAE) sobre el comportamiento productivo de pollos de engorde. Se alimentó durante 42 d a 200 pollos mixtos ROSS, de un día de edad y peso promedio de 37.2 g ± 0.89 g. El estudio se realizó en dos fases de 21 d: inicio y acabado. Se usó un diseño experimental al azar con arreglo factorial 2 x 2 con la fuente de lípidos (GF y AV), laconcentración de energía (DEE y DAE) y su interacción como efectos principales. La energía metabolizable en la fase de inicio fue 2 994 kcal/kg y 3 013 kcal/kg, y en la fase de acabado fue 3 081 kcal/kg y 3 111 kcal/kg en DEE y DAE, respectivamente. La fuente de lípidos no influyó (P > 0.05) sobre las variables de estudio. En la fase de inicio, los pollos alimentados con la DAE ganaron más peso y mostraron mejor conversión alimenticia (P < 0.05) que los pollos en la DEE, aunque el consumo de alimento fue similar (P > 0.05). En la fase de acabado, los pollos alimentados con la DAE ganaron más peso (P < 0.05) y consumieron más alimento (P < 0.05) que los pollos alimentados con la DEE. No se observó efecto de la concentración de energía sobre la conversión alimenticia (P > 0.05). Se concluyó que la fuente de lípidos no influyó en los parámetros productivos, pero el incremento en concentración energética mejoró significativamente el comportamiento productivo de los pollos de engorde. Archivo XML (SciELO)

Effects of energy concentration of the diet on productive performance and egg quality of brown egg-laying hens differing in initial body weight

The influence of AMEn concentration of the diet on productive performance and egg quality traits was studied in Hy-Line brown egg-laying hens differing in initial BW from 24 to 59 wk of age. Eight treatments were arranged factorially with 4 diets varying in energy content (2,650, 2,750, 2,850, and 2,950 kcal of AMEn/kg) and 2 initial BW of the hens (1,733 vs. 1,606 g). Each treatment was replicated 5 times (13 hens per replicate), and all diets had similar nutrient content per unit of energy. No interactions between energy content of the diet and initial BW of the hens were detected for any trait. An increase in energy concentration of the diet increased (linear, P < 0.05; quadratic P < 0.05) egg production, egg mass, energy efficiency (kcal of AMEn/g of egg), and BW gain (P < 0.05) but decreased ADFI (linear, P < 0.001) and feed conversion ratio per kilogram of eggs (linear, P < 0.01; quadratic P < 0.01). An increase in energy content of the diet reduced Haugh units and the proportion of shell in the egg (P < 0.01). Feed intake (114.6 vs. 111.1 g/hen per day), AMEn intake (321 vs. 311 kcal/hen per day), egg weight (64.2 vs. 63.0 g), and egg mass (58.5 vs. 57.0 g) were higher for the heavier than for the lighter hens (P < 0.01), but feed conversion ratio per kilogram of eggs and energy efficiency were not affected. Eggs from the heavier hens had a higher proportion of yolk and lower proportion of albumen (P < 0.01) and shell (P < 0.05) than eggs from the lighter hens. Consequently, the yolk-to-albumen ratio was higher (P < 0.001) for the heavier hens. It is concluded that brown egg-laying hens respond with increases in egg production and egg mass to increases in AMEn concentration of the diet up to 2,850 kcal/kg. Heavy hens had higher feed intake and produced heavier eggs and more egg mass than light hens. However, feed and energy efficiency were better for the lighter hens.

Growth and metabolism of pacu (Piaractus mesopotamicus Holmberg 1887) juveniles fed diets containing different protein, lipid and carbohydrate levels

To verify the potential of lipids and carbohydrates to spare dietary protein and to understand the intermediary metabolism of interaction of these nutrients in pacu juveniles, an experiment was carried out to evaluate pacu physiological and performance parameters. The experimental design was completely randomized with 12 treatments in a 2 × 2 × 3 factorial arrangement, consisting of diets containing two digestible protein levels (200 and 230 g kg−1 PD), two lipid levels (40 and 80 g kg−1) and three carbohydrate levels (410, 460 and 500 g kg−1). Fish-fed 230 g kg−1 digestable protein (DP) showed increased glycaemia, decreased hepatic glycogen, as well as a smaller intake index and better feed conversion ratio. The higher dietary lipid level (80 g kg−1) reduced protein intake and serum protein concentration, increased liver and body fat content, but did not affect growth. At a lipid level of 80 g kg−1, the increase in dietary carbohydrate levels promoted greater weight gain (WG), crude protein intake (CPI) and better feed conversion ratio (FCR). For fish fed diets containing 40 g kg−1 lipid, the best energy-productive values (EPV) were obtained at 460 g kg−1 carbohydrate. Increased levels of the main nutrients in the diets reduced the levels of serum triglycerides, while the increase in energy concentration increased the hepatosomatic (HSI) and glycaemia index values. Pacu used lipids as effectively as carbohydrates in the maximization of protein usage, as long as dietary protein was at a level of 230 g kg−1 DP. The physiological parameters indicated that the best balance between the DP, dietary lipid and carbohydrate levels within the ranged this trial was obtained at 230, 40 and 460 g kg−1, respectively, without lower growth.

Corn Silage Management: Effects of Hybrid, Chop Length, and Mechanical Processing on Digestion and Energy Content

Two experiments were conducted to evaluate the effects of chop length and mechanical processing of two hybrids of whole plant corn on digestion and energy content of the total mixed ration (TMR). The experimental designs in experiments 1 and 2 were 6×6 and 4×4 Latin squares, respectively. In the first experiment, Pioneer hybrid 3845 was harvested at three theoretical lengths of cut: 11.1, 27.8, and 39.7mm. At each chop length, corn was harvested with and without mechanical processing using a John Deere 5830 harvester with an onboard kernel processor. In the second experiment, Pioneer hybrid Quanta was harvested at two theoretical lengths of cut: 27.8 and 39.7mm, with and without mechanical processing. In both experiments, the increase in the theoretical length of cut of corn silage increased the average length of cut and tended to increase the percentage of particles greater than 19mm and lower the percentage of particles between 8 and 19mm. In experiment 1, apparent total tract dry matter, organic matter, and neutral detergent fiber (NDF) digestibilities were lower for cows fed diets containing corn silage harvested at a short chop length (11.1mm) than for corn silage harvested at a long chop length (39.7mm). The lower total tract digestibility of nutrients may have contributed to the lower TDN, metabolizable energy (percentage of digestible energy), and NEL concentration of diets containing the short chop length corn silage (experiment 1). In experiment 2, total tract starch digestibility was greater for cows fed medium chop (27.8mm) corn silage diets, and total tract NDF digestibility was greater for cows fed long chop (39.7mm) corn silage diets. The opposing effect of total tract starch and fiber digestibilities between chop lengths may have contributed to the lack of difference in energy content of the diets in experiment 2. The TDN and NEL concentrations of the processed corn silage diets were greater than the unprocessed corn silage diets in experiment 1. The increase in energy concentration for the processed corn silage diet was due to greater total tract digestibility of organic matter and ether extract. Total tract starch digestibility was greater, and total tract NDF digestibility was lower for cows fed processed corn silage diets than unprocessed corn silage diets in experiment 2. The opposing effect of total tract starch and fiber digestibilities between processed and unprocessed corn silage may have contributed to the lack of difference in energy content of the diets.

The effects of dietary fibre, source of fat and dietary energy concentration on the voluntary food intake and performance of growing pigs

ABSTRACTNinety entire male pigs were used in two experiments to investigate the effects of energy concentration on the performance of growing pigs given diets containing relatively high or low levels of fibre. A blended fat product was also compared with tallow as a source of dietary energy for pigs in the first experiment.In experiment 1, 60 pigs growing between 20 and 45 kg live weight were given 10 diets containing approximately 120 g acid-detergent fibre per kg (80 g crude fibre per kg), and 10, 30, 50, 75 or 100 g/kg of either tallow or the blended fat product.Although the source of fat had no significant effect on food intake or growth performance, voluntary energy intake and growth rate increased with increase in the level of fat added to the diet and with concomitant increase in dietary digestible energy (DE) concentration up to 50 g/kg and 13·2 MJ/kg respectively. Further increase in the level of fat added to the diet and in DE concentration resulted in a decline in voluntary food intake, whilst energy intake and growth rate remained relatively constant at 27 MJ/day and 720 g/day respectively.In experiment 2, 30 pigs were used to investigate the animals' response to five levels of dietary DE concentration (11·8 to 15·1 MJ DE per kg) between 20 and 50 kg live weight. The highest level of acid-detergent fibre in the diets was 62 g/kg (50 g crude fibre per kg) and this declined with increase in energy concentration to 30 g/kg (25 g crude fibre per kg) in the diet of highest energy concentration.Voluntary food intake was not significantly affected by dietary energy concentration, and voluntary energy intake and growth rate increased linearly with increase in dietary energy concentration up to 14·5 MJ DE per kg. Maximum energy intake (31 MJ DE per day) and growth rate (905 g/day) in experiment 2 was proportionately 0·15 and 0·26 higher than that achieved by pigs given the higher fibre diets in experiment 1.The results for voluntary food intake and growth rate suggested that the pig's demand for energy and consequently its response to dietary energy concentration was affected by dietary fibre concentration.

Energy changes during ensilage.

AbstractThe energy changes occurring during ensilage have been examined using a theoretical model with data calculated from known biochemical pathways. Results of a laboratory experiment in which five grasses were ensiled in triplicate confirm that energy is recoverable in an anaerobic system in spite of gaseous losses in the form of CO2. These changes have a concentrating effect upon the gross energy value of silage. The importance of this increase in energy concentration is discussed.