ABSTRACT The effects of diets containing oilseeds were measured to evaluate the productive and economic parameters in the finishing of young, feedlot Nellore bulls. Twenty-four young Nellore bulls were used, with an initial body weight (BW) of 311.46±0.37 kg and 24 months of age, distributed into individual stalls ( 4 × 20 m) in a completely randomized design, totaling four treatments with six repetitions per treatment. Four diets (control, based on corn and soybean meal, and three diets containing cottonseed, soybean, and sunflower) were evaluated. Feed and orts were measured daily to calculate intake and costs. The dry matter intake of the control group was higher than soybean (10.64 kg/day), cotton (9.88 kg/day), and sunflower (9.30 kg/day) treatments, respectively. The cottonseed treatment showed the highest average neutral detergent fiber intake. There was a dietary effect of diets on average daily gain, total weight gain, and final weight. The soybean treatment showed the highest performance, total gain (232.55 kg), and final weight (544.38 kg). Oilseed intake can modify the fatty acids profile in the meat, decreasing its saturated fatty acid content. Whole soybean seed favors performance, improves feed efficiency, fatty acid profile, and fat distribution in the carcass, and can reduce production costs.

RESUMO: Realizou-se este estudo com o objetivo de avaliar níveis de energia líquida (EL), mantendo a relação caloria: nutriente, no desempenho e características de carcaça de suínos dos 30 aos 70 kg. Foram utilizados 60 suínos machos castrados, com pesos iniciais de 31,94 ± 3,54 kg e finais de 71,98 ± 5,99 kg. Os animais foram distribuídos em delineamento experimental de blocos casualizados, em cinco níveis de EL (2,40; 2,45; 2,50; 2,55; 2,60 Mcal de EL kg-1 de dieta), com seis repetições e dois animais por unidade experimental. O período experimental foi dividido em fase I: 30 aos 50 kg e fase II: 50 aos 70 kg. As variáveis analisadas foram os consumos de ração diária (CRD), energia líquida (CEL) e lisina digestível (CLdig), ganho de peso diário (GPD), conversão alimentar (CA), peso final (PF), conversão de lisina digestível: ganho (CLdig:G), custo: ganho (C:G), área de olho de lombo (AOL), profundidade de músculo (PM), espessura de toucinho da primeira camada (ET1), espessura de toucinho da segunda camada (ET2), espessura de toucinho total (ETt), percentual de carne magra (CM) e o índice de bonificação de carcaça (IB). Dos 30 aos 50 kg, verificou-se aumento linear (P < 0,05) do PF, GPD e dos CEL e CLdig com o aumento dos níveis de EL na dieta. Dos 50 aos 70 kg, o aumento dos níveis de EL na dieta promoveu melhora linear (P < 0,05) do PF, GPD, CEL, CLdig e da CA dos suínos. No período total, verificou-se aumento linear (P < 0,05) do GPD, CEL, CLdig e melhora linear (P < 0,05) da CA de acordo com o aumento do nível de EL na dieta. As demais variáveis de desempenho não foram afetadas (P > 0,05) pelos níveis de EL. Verificou-se aumento (P < 0,05) da ET2 de acordo com o aumento do nível de EL, porém sem alterar (P > 0,05) as demais características de carcaça. Recomenda-se o nível 2,60 Mcal de EL kg-1 de dieta para suínos machos castrados dos 30 aos 70 kg.

ABSTRACT: This study evaluated the effect of dietary net energy (NE) levels on growth performance and carcass characteristics of barrows from 30 to 70 kg of body weight (BW). Sixty barrows with initial body weight (IBW) of 31.94 ± 3.54 kg and final body weight (FBW) of 71.98 ± 5.99 kg were allotted to one of five dietary NE levels (2.40, 2.45, 2.50, 2.55, and 2.60 Mcal kg-1), using a completely randomized block design with six replicates and two barrows per replicate. The experimental period was divided into phase I: 30 to 50 kg and phase II: 50 to 70 kg. The variables analyzed were average daily feed intake (ADFI), net energy intake (NEI), digestible lysine intake (LysI), average daily gain (ADG), feed conversion (FC), FBW, digestible lysine conversion:gain (LysI:G), Cost:Gain (C:G), loin eye area (LEA), muscle depth (MD), first backfat layer (BF1), second backfat layer (BF2), total backfat (BFt), lean meat percentage, and carcass bonus index (BI). In phase I, there was a linear increase (P < 0.05) in FBW, ADG, NEI, and LysI with increasing NE levels in the diet. In phase II, increasing dietary NE levels also increased (P < 0.05) FBW, ADG, NEI, LysI, and FC linearly. Overall, there was a linear increase (P < 0.05) in ADG, NEI, LysI, and FC with increasing NE levels in the diet. The other performance variables were not affected (P > 0.05) by the NE levels. There was an increase (P < 0.05) in BF2 with increasing NE levels, but the other carcass characteristics were not altered (P > 0.05). We recommended 2.60 Mcal of NE kg-1 in the diet for growing barrows from 30 to 70 kg.

ABSTRACT This experiment was conducted to evaluate growth performance and carcass characteristics of barrows from 25 to 100 kg fed diets with different dietary net energy (NE) levels. Seventy-two barrows with initial body weight (BW) of 25.19±2.13 kg were allotted using a completely randomized block design to one of six dietary NE treatments (2300, 2380, 2460, 2540, 2620, and 2700 kcal kg−1), which had two pigs per replicate and six replicates per treatment. Diets were formulated to be fed in three phases (25 to 60, 60 to 70, and 70 to 100 kg BW). The six different dietary NE densities were met by adding soybean oil in place of the inert ingredient (kaolin) to a corn-soybean meal-based diet. Increasing dietary NE decreased average daily feed intake and average daily standardized ileal digestible (SID) lysine intake in all of the three phases evaluated and improved the feed:gain ratio and SID lysine:gain ratio in the first and third phases. In the first and second phases, average daily NE intake and NE:gain ratio were similar among treatments, but NE increased and NE:gain worsened during the last phase as dietary NE increased. Average daily gain was not affected by dietary NE in the first and second phases; however, it improved in the last phase. Backfat was thicker, and lean percentage was reduced by increasing the dietary NE in all three phases of this study. Thus, barrows consume less feed, but carcass fat increases if dietary NE is increased from 2300 to 2700 kcal kg−1.

ABSTRACT This study was carried out to evaluate the levels of digestible phosphorus in diets for barrows with a high potential for lean meat deposition from 50 to 80 kg. Eighty barrows, with an initial weight of 47.93±3.43 kg, were distributed in completely randomized blocks, with each group given five levels of digestible phosphorus (1.86, 2.23, 2.61, 2.99, and 3.36 g kg−1). There were eight replicates, and two animals per experimental unit. Phosphorus levels did not significantly influence feed intake, weight gain, or feed conversion ratio. Daily digestible phosphorus intake increased linearly as levels of phosphorus in the diet were increased. Phosphorus levels did not significantly influence muscle depth, loin eye area, backfat thickness, or the percentage and quantity of lean meat in the carcass. A linear increase was observed for feeding cost as the levels of digestible phosphorus in the diet were increased, and the level of 1.86 g kg−1 cost 29.4% less when compared with the level of 2.61 g kg−1. The dry matter, natural matter, the coefficient of the residue, and volatile solids of the waste were not significantly influenced by phosphorus levels. Conversely, it was possible to observe an increasing linear effect for total solids, total phosphorus, and total nitrogen in the waste of animals receiving diets with increased levels of digestible phosphorus. The level of 1.86 g kg−1, which corresponded to a daily intake of 4.77 g−1 of digestible phosphorus, meets the requirements of barrows weighing 50 to 80 kg.

Carbon fiber reinforced composites (CFRC) have been used in aeronautical industry in the manufacture of different aircraft components that must attend tight mechanical requirements. This paper shows a study involving mechanical (flexural, shear, tensile and compressive tests) and morphological characterizations of four different laminates based on 2 epoxy resin systems (8552TM and F584TM) and 2 carbon fiber fabric reinforcements (Plain Weave (PW) and Eight Harness Satin (8HS)). All laminates were obtained by handing lay-up of prepregs plies (0º/90º) and consolidation in an autoclave following an appropriate curing cycle with vacuum and pressure. The results show that the F584-epoxy matrix laminates present better mechanical properties in the tensile and compressive tests than 8552 composites. It is also observed that PW laminates for both matrices show better flexural and interlaminar shear properties.