RESUMO

Alpacas are well adapted to consume the poor-quality forages present in the arid conditions of the Andean Altiplano. However, studies focusing on understanding the relationship between diet digestibility and intake are scarce. The aim of this study was to evaluate the effects of two levels of dry matter intake (DMI) on a metabolic body weight (BW0.75) basis. The effects of a maintenance level of intake and an ad libitum level of intake (40 and 50 g of dry matter (DM) per kg of BW0.75, respectively) on the apparent diet digestibility and partitioning of specific nutrients (energy, carbon (C), and nitrogen (N)) of alpacas that were fed a blend of oat hay and alfalfa pellets (70:30 ratio as a percentage on a fed basis) were evaluated. Five adult intact male alpacas (BW = 62.9 ± 8.09 kg at the beginning of the study) were fed with the experimental diet and trained to be allocated in metabolism crates for 30 days. After the completion of this phase, two separate experiments for each level of intake were carried out, each lasting for twenty-six days (with the final five days taken for samples and raw data collection). In both experiments, the animals responded differently in terms of nutrient supply and changes in BW (-140 and 100 g/d for the maintenance and ad libitum levels of intake, respectively). Oat hay consumption was rather similar in both experiments, which may be explained by a reduced ingredient selectivity at the ad libitum level of intake. Diet digestibility was similar in both experiments, despite the greater fecal output of nutrients with the increased level of diet intake. In line with this, diet metabolizability, calculated as the ratio between metabolizable energy (ME) and gross energy (GE) contents, indicated a similar energy utilization of the diet. The apparent digestibility of the organic matter (OMD) ranged from 655 to 669 g/kg DM. Water consumption at the ad libitum level of intake was 21% higher than the observed mean at the maintenance level of intake. Fecal outputs of dietary energy, C, and N accounted for the largest source of excreted nutrients, regardless of the level of intake. The N retention increased from 0.439 at the maintenance level of intake, to 0.473 g of DM/kg BW0.75 when the alpacas were fed ad libitum.

RESUMO

Abstract This research evaluated the monthly variation of plant mineral nutrition in six species of fruit trees over a year. Leaf samples were taken from the fruit trees and nutritional status (N, P, K, Ca, Mg, Fe, Zn, Cu, Mn, and Mo) was determined in the leaves in a month basis from April until November for apple, persimmon and peach. Mandarin mineral nutrition was monitored for one year, and grape and fig from May to November. Using this data, the Diagnosis Recommendation Integrated System (DRIS) was also calculated to evaluate the nutrient balance in the plants. The concentration of N and P had seasonal differences, especially in apple and peach, which reached the peak during the summer. Apple, fig, and grape trees had large ranging on their mineral contents over the year, especially with the P and K levels reaching the minimum during the harvesting season. However, the seasonal changes in leaf micronutrient concentrations were not uniform and not affected by phenological stage. The DRIS data demonstrated that mandarin had the best nutrient balance compared to others and that K was the most limiting element among the fruit trees. In summary, the current data suggest the occurrence of a significant seasonality in mineral nutrition in these six fruit trees, especially in temperate ones.

Assuntos

RESUMO

This study evaluated the functional effects of two chemotypes of oregano essential oil (OEO): Lippia Origanoides (LO) and a comercial product Synergy Essence (SE). Broilers were randomly assigned to one of eight dietary treatments: 1) Basal diet (BD); 2) BD+ antibiotic growth promoters (AGP) (bacitracin 50g/ton); 3) BD+LO125 (125g/ton); 4) BD+LO250 (250g/ton); 5) BD+LO500 (500g/ton); 6) BD+SE125 (125g/ton); 7) BD+SE250 (250g/ton); 8) BD+SE500 (500g/ton). At the time of slaughter (42 d), five birds per treatment were slaughtered. A portion of the breast was minced and stored at -4 ºC for 3, 6, and 9 days. Lipid peroxidation was determined by measuring of malondialdehyde (MDA), data were analyzed as a completely randomized design with a factorial arrangement of treatments (8x4). Broilers fed SE250 had greater average daily gain (ADG) compared to broilers fed BD (P<0.05). Broilers fed LO500 had greater (P<0.05) organic matter digestibility than the ones fed BD. As days of storage increased, MDA concentration increased (P<0.05). Broilers fed SE500 had lower (P<0.05) MDA concentration than those fed BD and AGP. These data indicate that birds fed OEO grow faster than those fed a BD, similar to birds fed AGP. Some of these responses are possibly explained by increased digestibility and energy utilization. In addition, providing OEO from SE at 500g/ton resulted in lower lipid peroxidation in ground breast meat throughout the tested storage time.(AU)

Este estudo avaliou os efeitos funcionais de dois quimiótipos de óleo esencial de orégano (OEO): Lippia Origanoides (LO) e um produto comercial Synergy Essence (SE). Os frangos de corte foram distribuídos aleatoriamente para um dos oito tratamentos dietéticos: 1) Dieta basal (BD); 2) BD + antibiótico promotor de crescimento (AGP) (bacitracina 50 g/tonelada); 3) BD + LO125 (125 g/tonelada); 4) BD + LO250 (250 g/tonelada); 5) BD + LO500 (500 g/tonelada); 6) BD + SE125 (125 g/tonelada); 7) BD + SE250 (250 g/tonelada); 8) BD + SE500 (500g/tonelada). No momento do abate (42 d), cinco aves por tratamento foram abatidas. Uma porção do peito foi picada e armazenada a -4 ºC durante 3, 6 e 9 dias. A peroxidação lipídica foi determinada pela medição de malondialdeído (MDA), os dados foram analisados ​​como um delineamento inteiramente casualizado com um arranjo fatorial de tratamentos (8x4). Os frangos alimentados com SE250 apresentaram maior ganho diário médio (ADG) em comparação com o BD (P <0,05). Os frangos alimentados com LO500 apresentaram maior digestibilidade da matéria orgânica (P <0,05) do que BD. À medida que o dia do armazenamento aumentou, a concentração de MDA aumentou (P <0,05) Os frangos de corte alimentados com SE500 apresentaram menor concentração de MDA (BD <0,05) do que BD e AGP. Esses dados indicam que as aves alimentadas com OEO crescem mais rápido do que aquelas alimentadas com BD e semelhantes às aves alimentadas com AGP, com algumas dessas respostas sendo possivelmente explicadas pelo aumento da digestibilidade e da utilização de energia, além de fornecer OEO do SE a 500g/ton, frangos de corte resulta em menor Peroxidação lipídica na carne de peito moída ao longo do tempo de armazenamento testado.(AU)

Assuntos

RESUMO

This study evaluated the functional effects of two chemotypes of oregano essential oil (OEO): Lippia Origanoides (LO) and a comercial product Synergy Essence (SE). Broilers were randomly assigned to one of eight dietary treatments: 1) Basal diet (BD); 2) BD+ antibiotic growth promoters (AGP) (bacitracin 50g/ton); 3) BD+LO125 (125g/ton); 4) BD+LO250 (250g/ton); 5) BD+LO500 (500g/ton); 6) BD+SE125 (125g/ton); 7) BD+SE250 (250g/ton); 8) BD+SE500 (500g/ton). At the time of slaughter (42 d), five birds per treatment were slaughtered. A portion of the breast was minced and stored at -4 ºC for 3, 6, and 9 days. Lipid peroxidation was determined by measuring of malondialdehyde (MDA), data were analyzed as a completely randomized design with a factorial arrangement of treatments (8x4). Broilers fed SE250 had greater average daily gain (ADG) compared to broilers fed BD (P<0.05). Broilers fed LO500 had greater (P<0.05) organic matter digestibility than the ones fed BD. As days of storage increased, MDA concentration increased (P<0.05). Broilers fed SE500 had lower (P<0.05) MDA concentration than those fed BD and AGP. These data indicate that birds fed OEO grow faster than those fed a BD, similar to birds fed AGP. Some of these responses are possibly explained by increased digestibility and energy utilization. In addition, providing OEO from SE at 500g/ton resulted in lower lipid peroxidation in ground breast meat throughout the tested storage time.

Este estudo avaliou os efeitos funcionais de dois quimiótipos de óleo esencial de orégano (OEO): Lippia Origanoides (LO) e um produto comercial Synergy Essence (SE). Os frangos de corte foram distribuídos aleatoriamente para um dos oito tratamentos dietéticos: 1) Dieta basal (BD); 2) BD + antibiótico promotor de crescimento (AGP) (bacitracina 50 g/tonelada); 3) BD + LO125 (125 g/tonelada); 4) BD + LO250 (250 g/tonelada); 5) BD + LO500 (500 g/tonelada); 6) BD + SE125 (125 g/tonelada); 7) BD + SE250 (250 g/tonelada); 8) BD + SE500 (500g/tonelada). No momento do abate (42 d), cinco aves por tratamento foram abatidas. Uma porção do peito foi picada e armazenada a -4 ºC durante 3, 6 e 9 dias. A peroxidação lipídica foi determinada pela medição de malondialdeído (MDA), os dados foram analisados ​​como um delineamento inteiramente casualizado com um arranjo fatorial de tratamentos (8x4). Os frangos alimentados com SE250 apresentaram maior ganho diário médio (ADG) em comparação com o BD (P <0,05). Os frangos alimentados com LO500 apresentaram maior digestibilidade da matéria orgânica (P <0,05) do que BD. À medida que o dia do armazenamento aumentou, a concentração de MDA aumentou (P <0,05) Os frangos de corte alimentados com SE500 apresentaram menor concentração de MDA (BD <0,05) do que BD e AGP. Esses dados indicam que as aves alimentadas com OEO crescem mais rápido do que aquelas alimentadas com BD e semelhantes às aves alimentadas com AGP, com algumas dessas respostas sendo possivelmente explicadas pelo aumento da digestibilidade e da utilização de energia, além de fornecer OEO do SE a 500g/ton, frangos de corte resulta em menor Peroxidação lipídica na carne de peito moída ao longo do tempo de armazenamento testado.

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RESUMO

Over the past 20 years, the use of center-pivot irrigation has increased tomato (Solanum lycopersicum L.) yields in Brazil from 42 Mg ha-1 to more than 80 Mg ha-1. In the absence of field trials to support fertilizer recommendations, substantial amounts of phosphorus (P) have been applied to crops. Additional P dosing has been based on an equilibrated nutrient P budget adjusted for low-P fertilizer-use efficiency in high-P fixing tropical soils. To document nutrient requirements and prevent over-fertilization, tissue samples and crop yield data can be acquired through crop surveys and fertilizer trials. Nevertheless, most tissue diagnostic methods pose numerical difficulties that can be avoided by using the nutrient balance concept. The objectives of this study were to model the response of irrigated tomato crops to P fertilization in low- and high-P soils and to provide tissue diagnostic models for high crop yield. Three P trials, arranged in a randomized block design with six P treatments (0-437 kg P ha-1) and three or four replications, were established on a low-P soil in 2013 and high-P soils in 2013 and 2014, totaling 66 plots in all. Together with crop yield data, 65 tissue samples were collected from tomato farms. We found no significant yield response to P fertilization, despite large differences in soil-test P (coefficient of variation, 24%). High- and low-yield classes (cutoff: 91 Mg fruits ha-1) were classified by balance models with 78-81% accuracy using logit and Cate-Nelson partitioning models. The critical Mahalanobis distance for the partition was 5.31. Tomato yields were apparently not limited by P but were limited by calcium. There was no evidence that P fertilization should differ between center-pivot-irrigated and rain-fed crops. Use of the P budget method to arrive at the P requirement for tomato crops proved to be fallacious, as several nutrients should be rebalanced in Brazilian tomato cropping systems.

RESUMO

The Brazilian guava processing industry generates 5.5 M Mg guava waste year(-1) that could be recycled sustainably in guava agro-ecosystems as slow-release fertilizer. Our objectives were to elaborate nutrient budgets and to diagnose soil, foliar, and fruit nutrient balances in guava orchards fertilized with guava waste. We hypothesized that (1) guava waste are balanced fertilizer sources that can sustain crop yield and soil nutrient stocks, and (2) guava agroecosystems remain productive within narrow ranges of nutrient balances. A 6-year experiment was conducted in 8-year old guava orchard applying 0-9-18-27-36 Mg ha(-1) guava waste (dry mass basis) and the locally recommended mineral fertilization. Nutrient budgets were compiled as balance sheets. Foliar and fruit nutrient balances were computed as isometric log ratios to avoid data redundancy or resonance due to nutrient interactions and the closure to measurement unit. The N, P, and several other nutrients were applied in excess of crop removal while K was in deficit whatever the guava waste treatment. The foliar diagnostic accuracy reached 93% using isometric log ratios and knn classification, generating reliable foliar nutrient and concentration ranges at high yield level. The plant mined the soil K reserves without any significant effect on fruit yield and foliar nutrient balances involving K. High guava productivity can be reached at lower soil test K and P values than thought before. Parsimonious dosage of fresh guava waste should be supplemented with mineral K fertilizers to recycle guava waste sustainably in guava agroecosystems. Brazilian growers can benefit from this research by lowering soil test P and K threshold values to avoid over-fertilization and using fresh guava waste supplemented with mineral fertilizers, especially K. Because yield was negatively correlated with fruit acidity and Brix index, balanced plant nutrition and fertilization diagnosis will have to consider not only fruit yield targets but also fruit quality to meet requirements for guava processing.

RESUMO

The aim of this study was to determine the net requirements of calcium (Ca), phosphorus (P), magnesium (Mg), and sulphur (S) for weight gain of non-descript breed hair lambs (NDBL) of different sex classes reared under Brazilian semiarid conditions. Sixty NDBL (20 intact males, 20 castrated males, and 20 females), with an average initial body weight of 18.1 ± 0.4 kg and average age of 5 months were used. The macromineral requirements were determined by the differences in body composition through comparative slaughter direct method. The animals were confined for 58 days, and the average fasting body weight (FBW) and average daily gain (ADG) of lambs fed ad libitum were 29.2 ± 0.6 and 0.19 ± 0.01 kg, respectively. The net requirements of macrominerals for gain of NDBL did not differ between sex classes (P > 0.05), and ranged from 1.83 to 1.46 g/day of Ca, 1.21 to 1.01 g/day of P, 37 to 30 mg/day of Mg, and 0.31 to 0.28 g/day of S, for lambs with an ADG of 0.200 kg and 15 or 30 kg of FBW, respectively (P < 0.05). The N to S net ratio reduced and increased, respectively, as the body weight and ADG increase. The net requirements of Ca, P, Mg, and S for gain of NDBL slaughtered young and at the same age did not differ between sex classes and decreased as the body weight increased. The net requirements for gain of Ca and P were similar to those recommended by NRC (2007).

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RESUMO

Most of amino acid (AA) digestibility values for feed ingredients are obtained using pigs cannulated in the distal ileum. The ileal-cannulated pig model uses pigs older than six weeks due to difficulties related to implanting the T-cannula in distal ileum of younger pigs and complications during the post-surgical recovery. However, to properly formulate the diet of weaned pigs, the nutritive value of feed ingredients should be determined with younger pigs. Thus, 25 weaned pigs were used to determine the apparent total tract digestibility (ATTD) of nutrients, energy, and apparent ileal digestibility (AID) and standardized ileal digestibility (SID) ileal AA digestibility of broken rice (BR), with or without multicarbohydrase (MC) and phytase (Phy) supplementation. Piglets were weaned at 23 d of age and individually housed in digestibility cages until 45 d of age. The trial consisted of 7 d of adaptation to the experimental diets and 3 d of excreta (feces and urine) collection. Ileal digesta was collected at slaughter (about 6 weeks of age). A completely randomized experimental design was used to determine the effects of MC and Phy. Reference diets (RD, 5% casein) was replaced by 30% of BR with or without MC, Phy, or MC+Phy. The RD was used to quantify endogenous AA losses. BR with Phy supplied had increased the ATTD of dry matter (p<0.05) and SID of histidine (p = 0.05), arginine, leucine, lysine, valine, alanine, and proline (p<0.05). BR with MC had been increased digestible energy and protein and SID for histidine (p<0.05). There was no interaction between Phy and MC on the BR nutrient digestibilities. Standardized amino acid digestibilities of BR, without enzymes, were lower than those values reported in the literature. The MC and Phy improved the digestibility of some nutrients and energy of BR in post-weaned piglet diets.

RESUMO

Arsenic (As) hyperaccumulation trait has been described in a limited number of fern species. The physiological basis of hyperaccumulation remains unclear, especially in non-Pteris species such as Pityrogramma calomelanos. Aiming at a better understanding of As-induced responses, P. calomelanos plants were exposed to 1 mM As for 21 days and compared with control plants. Chemical analyses revealed that As accumulation was ten times higher in pinnae then in roots and stipes. In pinnae, As was present mainly as arsenite, whereas arsenate was the dominant form in stipes and roots. Arsenic promoted an increase in antioxidant enzyme activities in both fern parts and several alterations in mineral nutrition, especially with regard to P and K. A higher content of non-protein thiols was observed in pinnae of plants exposed to As, whereas As induced the increase in lipid peroxidation in roots. The results showed that Pityrogramma calomelanos shares with Pteris vittata several aspects of As metabolism. High root-shoot As translocation showed to be essential to avoid toxic effects in roots, since the root is more sensitive to the metalloid. The higher capacity of P. calomelanos to sequester arsenite in the pinna and its efficient antioxidant system maintain the reactive oxygen species at a low level, thus enhancing the continuous accumulation of As. Molecular investigations are needed to elucidate the evolution of As-tolerance mechanisms in Pteridaceae species, especially with regard to membrane transporters and ROS signaling.

Assuntos

RESUMO

The objective of this research was to evaluate the growth performance, the apparent ileal digestibility of nitrogen and energy, the retention of nutrients and the apparent metabolizable energy corrected to zero nitrogen retention (AMEn) in broiler chickens supplemented with increasing doses of a worm leachate (WL) as a source of humic substances (HS) in the drinking water. In Exp. 1, 140 male broilers were penned individually and assigned to four WL levels (0%, 10%, 20%, and 30%) mixed in the drinking water from 21 to 49 days of age. Water was offered in plastic bottles tied to the cage. In Exp. 2, 600 male broilers from 21 to 49 days of age housed in floor pens were assigned to three levels of WL (0%, 10%, and 20%) mixed in the drinking water. The WL was mixed with tap water in plastic containers connected by plastic tubing to bell drinkers. The results of both experiments were subjected to analysis of variance and polynomial contrasts. In Exp. 1, the daily water consumption was similar among treatments but the consumption of humic, fulvic, and total humic acids increased linearly (p<0.01) as the WL increased in the drinking water. The feed conversion (p<0.01) and the ileal digestibility of energy, the excretion of dry matter and energy, the retention of dry matter, ash and nitrogen and the AMEn showed quadratic responses (p<0.05) relative to the WL levels in drinking water. In Exp. 2, the increasing level of WL in the drinking water had quadratic effects on the final body weight, daily weight gain and feed conversion ratio (p<0.05). The addition of WL as a source of HS in the drinking water had beneficial effects on the growth performance, ileal digestibility of energy, the retention of nutrients as well on the AMEn in broiler chickens; the best results were observed when the WL was mixed at levels of 20% to 30% in the drinking water.

RESUMO

Foram conduzidos dois experimentos com o objetivo de avaliar os efeitos da suplementação enzimática das rações à base de milho e farelo de soja sobre o desempenho e metabolizabilidade dos nutrientes em codornas de corte. Os tratamentos foram: controle positivo para atendimento das exigências; controle positivo suplementado com complexo enzimático e controles negativos suplementados reduzidos em 2 e 4% nos teores de energia metabolizável e aminoácidos. Na fase inicial, observou-se aumento no consumo de ração (p < 0,05) no tratamento controle negativo reduzido em 4% na energia metabolizável e aminoácidos em comparação aos tratamentos controle positivos. Na fase de crescimento o consumo de ração, conversão alimentar e rendimento de carcaça não diferiram (p > 0,05). Conclui-se que o complexo enzimático pode ser utilizado em dietas reduzidas em energia metabolizável e aminoácidos sem prejudicar o desempenho de codornas de corte. No ensaio de metabolismo, não foram observadas diferenças (p > 0,05) entre os tratamentos para os coeficientes de metabolização das matérias seca e orgânica, proteína bruta e energia bruta. O coeficiente de metabolização da FDN melhorou (p < 0,05) com a adição de enzimas.

Two experiments were carried out to evaluate the effects of enzyme supplementation (xylanase + ß-glucanase) of diets based on corn and soybean meal on: performance in initial (1-14 days) and growing (15-35 days) phases, and nutrient metabolization of meat-type quails. The treatments were: positive control to meet the nutritional requirements of the specie; positive control supplemented with enzyme complex; and negative controls with two reduced supplementation levels of metabolizable energy and amino acids (by 2% and 4%). In the initial phase, the negative control treatment reduced by 4% of metabolizable energy and amino acids increased feed intake (p < 0.05), compared to positive controls. In the growing phase, there were no differences (p > 0.05) in feed intake, feed conversion ratio and carcass traits. In conclusion, this supplementation can be used successfully in diets with reduced metabolizable energy and amino acid contents for meat-type quails. In the metabolism trial, there were no differences (p > 0.05) in metabolizable coefficients of dry matter, organic matter, crude protein and gross energy among treatments. The metabolization coefficient of NDF improved (p < 0.05) with enzyme supplementation.

Assuntos

RESUMO

Two experiments were carried out to evaluate the effects of enzyme supplementation (xylanase + -glucanase) of diets based on corn and soybean meal on: performance in initial (1-14 days) and growing (15-35 days) phases, and nutrient metabolization of meat-type quails. The treatments were: positive control to meet the nutritional requirements of the specie; positive control supplemented with enzyme complex; and negative controls with two reduced supplementation levels of metabolizable energy and amino acids (by 2% and 4%). In the initial phase, the negative control treatment reduced by 4% of metabolizable energy and amino acids increased feed intake (p 0.05), compared to positive controls. In the growing phase, there were no differences (p > 0.05) in feed intake, feed conversion ratio and carcass traits. In conclusion, this supplementation can be used successfully in diets with reduced metabolizable energy and amino acid contents for meat-type quails. In the metabolism trial, there were no differences (p > 0.05) in metabolizable coefficients of dry matter, organic matter, crude protein and gross energy among treatments. The metabolization coefficient of NDF improved (p 0.05) with enzyme supplementation.

Foram conduzidos dois experimentos com o objetivo de avaliar os efeitos da suplementação enzimática das rações à base de milho e farelo de soja sobre o desempenho e metabolizabilidade dos nutrientes em codornas de corte. Os tratamentos foram: controle positivo para atendimento das exigências; controle positivo suplementado com complexo enzimático e controles negativos suplementados reduzidos em 2 e 4% nos teores de energia metabolizável e aminoácidos. Na fase inicial, observou-se aumento no consumo de ração (p 0,05) no tratamento controle negativo reduzido em 4% na energia metabolizável e aminoácidos em comparação aos tratamentos controle positivos. Na fase de crescimento o consumo de ração, conversão alimentar e rendimento de carcaça não diferiram (p > 0,05). Conclui-se que o complexo enzimático pode ser utilizado em dietas reduzidas em energia metabolizável e aminoácidos sem prejudicar o desempenho de codornas de corte. No ensaio de metabolismo, não foram observadas diferenças (p > 0,05) entre os tratamentos para os coeficientes de metabolização das matérias seca e orgânica, proteína bruta e energia bruta. O coeficiente de metabolização da FDN melhorou (p 0,05) com a adição de enzimas.

RESUMO

Two experiments were carried out to evaluate the effects of enzyme supplementation (xylanase + -glucanase) of diets based on corn and soybean meal on: performance in initial (1-14 days) and growing (15-35 days) phases, and nutrient metabolization of meat-type quails. The treatments were: positive control to meet the nutritional requirements of the specie; positive control supplemented with enzyme complex; and negative controls with two reduced supplementation levels of metabolizable energy and amino acids (by 2% and 4%). In the initial phase, the negative control treatment reduced by 4% of metabolizable energy and amino acids increased feed intake (p 0.05), compared to positive controls. In the growing phase, there were no differences (p > 0.05) in feed intake, feed conversion ratio and carcass traits. In conclusion, this supplementation can be used successfully in diets with reduced metabolizable energy and amino acid contents for meat-type quails. In the metabolism trial, there were no differences (p > 0.05) in metabolizable coefficients of dry matter, organic matter, crude protein and gross energy among treatments. The metabolization coefficient of NDF improved (p 0.05) with enzyme supplementation.

Foram conduzidos dois experimentos com o objetivo de avaliar os efeitos da suplementação enzimática das rações à base de milho e farelo de soja sobre o desempenho e metabolizabilidade dos nutrientes em codornas de corte. Os tratamentos foram: controle positivo para atendimento das exigências; controle positivo suplementado com complexo enzimático e controles negativos suplementados reduzidos em 2 e 4% nos teores de energia metabolizável e aminoácidos. Na fase inicial, observou-se aumento no consumo de ração (p 0,05) no tratamento controle negativo reduzido em 4% na energia metabolizável e aminoácidos em comparação aos tratamentos controle positivos. Na fase de crescimento o consumo de ração, conversão alimentar e rendimento de carcaça não diferiram (p > 0,05). Conclui-se que o complexo enzimático pode ser utilizado em dietas reduzidas em energia metabolizável e aminoácidos sem prejudicar o desempenho de codornas de corte. No ensaio de metabolismo, não foram observadas diferenças (p > 0,05) entre os tratamentos para os coeficientes de metabolização das matérias seca e orgânica, proteína bruta e energia bruta. O coeficiente de metabolização da FDN melhorou (p 0,05) com a adição de enzimas.

RESUMO

The nitrogen and energy utilization of finishing pigs allocated individually or in groups of two was evaluated. Thirty two castrated males were used with an initial weight of 68.6 ± 1.0 kg that were assigned in a randomized complete block design with a split-plot arrangement in three treatments: a pig allocated individually with free access to feed and 0.81 m² of floor space (D1AL); two pigs allocated in group with free access to feed and 0.405 m² of floor space/pig (D2AL); a pig allocated individually paired-fed to the average consumption of pigs in D2AL and floor space similar to D1AL (D1P). The experiment was divided in two periods of excreta collection: days 1-4 and 18-21, respectively. There were eight repetitions per treatment. The nutrient consumption in period 1 was higher in D1AL compared to D2AL and D1P (density x period, P < 0.01); in period 2, the nutrient consumption was higher in D1AL, intermediate in D1P and lower in D2AL. The nitrogen (P < 0.05) and energy (P < 0.10) retained in period 1 was similar among densities (density x period interaction); in period 2 it was higher in D1AL compared to D2AL. The pigs housed in groups of two with free access to feed had lower nutrient consumption and retention at the end of the trial, probably as a consequence of chronic stress due to the competition for the feed, complicated by the restriction of available floor space.

Se evaluó la utilización de nitrógeno y energía en cerdos en finalización, alojados individualmente y en grupos de dos. Se usaron 32 machos castrados con un peso inicial de 68.6 ± 1.0 kg que fueron asignados al azar, en un diseño de bloques completos con arreglo en parcelas divididas en tres tratamientos: un cerdo alojado individualmente con libre acceso al alimento y 0.81 m² de espacio de piso (D1AL); dos cerdos alojados en grupo con libre acceso al alimento y 0.405 m² de espacio de piso/cerdo (D2AL); un cerdo alojado individualmente con consumo pareado con base en el consumo de los cerdos en D2AL y espacio de piso similar a D1AL (D1P). El experimento se dividió en dos periodos de recolección de excretas: días 1-4 (periodo 1) y 18-21 (periodo 2). Se tuvieron ocho repeticiones por tratamiento. El consumo de nutrimentos en el periodo 1 fue mayor en D1AL con respecto a D2AL y D1P (densidad x periodo, P < 0.01); en el periodo 2, el consumo de nutrimentos fue mayor en D1AL, intermedio en D1P y menor en D2AL. La retención de nitrógeno (P < 0.05) y de energía (P < 0.10) en el periodo 1 fue similar entre densidades (interacción densidad x periodo); en el periodo 2 fue mayor en D1AL comparado con D2AL. Los cerdos alojados en grupos de dos con alimentación a libertad tuvieron menor consumo y retención de nutrimentos en la fase final de la prueba, probablemente como consecuencia del estrés crónico debido a la competencia por el alimento, complicado por la restricción de espacio disponible de piso.