Digestible Threonine Levels in the Starter Diet of Broilers Derived from Breeders of Different Ages Laboissiere M III Racanicci AMC I Café MB II,IV

ABStRACt The aim of this study was to evaluate the effect of digestible threonine supplementation in the starter diet on the performance, intestinal parameters, and nutrient metabolism of broilers derived from breeders of different ages. In total, 480 one-day-old Cobb chicks, derived from 38-or 49-week-oldbreeders, were housed in experimental battery cages until 21 days of age and fed four different threonine levels (800, 900, 1,000, or 1,100 mg/kg) in the starter feed. A completely randomized experimental design in a 2x4 factorial arrangement (breeder age x threonine levels) was applied, totaling eight treatments with five replicates of 12 birds each. Broilers from older breeders fed 800 mg digestible threonine/kg of diet presented higher weight gain, with a positive linear effect. There was also an interaction between breeder age and threonine levels for the weight gain of 21-d-old broilers supplemented at maximum level of 1,003 mg Thr/kg diet during the starter phase. There was no effect of breeder age or threonine levels on nutrient metabolism during the period of 17-21 days. There was no influence of breeder age or threonine levels in the starter diet on intestinal morphometric measurements, absorption area, or percentage of goblet cells

PERFORMANCE AND NUTRIENT METABOLIZABILITY IN BROILERS FED DIETS CONTAINING CORN CONTAMINATED WITH FUMONISIN B1 AND ESTERIFIED GLUCOMANNAN

ABSTRACTAn experiment was conducted to evaluate the performance and nutrient metabolizability of broilers fed diets containing fumonisin B1 (FB1) and an esterified glucomannan (EGM). In total, 420 male broilers were distributed according to a 3 x 2 + 1 factorial arrangement, corresponding to three FB1 exposure times (seven, 21, or 35 days), two dietary glucomannan addition levels (0 or 0.1% EGM), and control diet, totaling seven treatments. The following diets were fed: 1) Control diet, 2) pre-starter diet containing FB1, 3) pre-starter diet containing FB1 and 0.1% EGM, 4) starter diet containing FB1, 5) starter diet containing FB1 and 0.1% EGM, 6) grower diet containing FB1, and 7) grower diet containing FB1 and 0.1% EGM. On d 7, broilers fed FB1 presented lower body weight gain and feed intake (p<0.05) compared with control treatment. On d 21, no significant performance differences were detected among treatment groups (p>0.05). At 35 days of exposure to FB1 body weight gain was reduced (p<0.05) compared with broilers fed fumonisin B1 for seven days. From 4 to 7 days and 18 to 21 days of age, FB1 reduced nutrient metabolizability (p<0.05). From 36 to 39 days of age, the EGM allowed maintaining apparent metabolizability for ether extract. It was concluded that the EGM did not reduce FB1 effects on performance or nutrient metabolizability in broilers, except for apparent metabolizability of ether extract

Digestible Threonine Levels in the Starter Diet of Broilers Derived from Breeders of Different Ages

ABSTRACT The aim of this study was to evaluate the effect of digestible threonine supplementation in the starter diet on the performance, intestinal parameters, and nutrient metabolism of broilers derived from breeders of different ages. In total, 480 one-day-old Cobb chicks, derived from 38-or 49-week-oldbreeders, were housed in experimental battery cages until 21 days of age and fed four different threonine levels (800, 900, 1,000, or 1,100 mg/kg) in the starter feed. A completely randomized experimental design in a 2x4 factorial arrangement (breeder age x threonine levels) was applied, totaling eight treatments with five replicates of 12 birds each. Broilers from older breeders fed 800 mg digestible threonine/kg of diet presented higher weight gain, with a positive linear effect. There was also an interaction between breeder age and threonine levels for the weight gain of 21-d-old broilers supplemented at maximum level of 1,003 mg Thr/kg diet during the starter phase. There was no effect of breeder age or threonine levels on nutrient metabolism during the period of 17-21 days. There was no influence of breeder age or threonine levels in the starter diet on intestinal morphometric measurements, absorption area, or percentage of goblet cells

Effects of the Dietary Supplementation of Sucupira (Pterodon Emarginatus Vog.) and Copaiba (Copaifera Langsdorffii) Resinoils on Chicken Breast and Thigh Meat Quality and Oxidative Stability

ABSTRACT An experiment was conducted to evaluate the addition of the oil resins ofsucupira (Pterodon emarginatus Vog.) and copaiba (Copaifera langsdorffii) to broiler diets on chicken meat composition, quality, and lipid peroxidation. 350 one-d-old broiler chicks were submitted to seven treatments, consisting of the diets supplemented with copaiba (COP) or sucupira (SUC) resin oils at three different concentrations (500, 900, and 1300 ppm) plus a negative control diet (CONT). At 37 days of age, 10 birds per treatment were selected according to the average weight of the experimental unit and slaughtered to collect breast and thigh meat, which was stored at 4°C for 24 hours to evaluate pH, color (L*, a*, b*), cooking weight loss (CWL), and shear force (SF). Raw meat was vacuum packed and stored frozen until lipid peroxidation analysis. Meat samples were pooled to prepare pre-cooked meatballs (30 ± 0.5g), stored under refrigeration (eight days), and analyzed every two days for TBARS concentration. Results were analyzed using the PROC GLM and MIXED procedures (SAS statistical software). Plant oils increased (p<0.05) breast meat humidity (HU) and crude protein (CP) levels and reduced (p<0.05) total lipid (TLC) and ash (AS) levels when compared with the CONT treatment. Plant oils increased (p<0.05) thigh meat HU when compared with the CONT. High COP dietary levels reduced (p<0.05) breast meat CWL, and increased (p<0.05) thigh meat L* values when compared to CONT, except for SUC500 and SUC900. The dietary inclusion of plant oil resins showed a pro-oxidant effect (p<0.01) on breast meat when compared with the CONT. Low SUC dietary supplementation levels significantly reduced (p<0.01) the concentration of secondary oxidation products in thigh meat

Dietary Supplementation of Barbatimão (Stryphnodendron Adstringens) and Pacari (Lafoensia Pacari) Extracts on the Oxidative Stability and Quality of Chicken Meat

ABSTRACT In order to evaluate the antioxidant effects of barbatimão (BAR) or pacari (PAC) on chicken meat oxidative stability and quality, seven dietary treatments containing in three different BAR and PAC concentrations (200, 400 and 600ppm) plus a negative control (CONT) were fed to 350 broilers from 1 to 41 days of age. Ten birds per treatment were slaughtered to collect breast and thigh meat to evaluate pH, color (L*, a*, b*), cooking weight loss (CWL), and shear force (SF) 24 hours postmortem, and TBARS levels in precooked meatballs stored chilled for 8days. The dietary supplementation with BAR and PAC extracts did not affect pH and color, but reduced (p<0.05) SF in breast meat compared with CONT suggesting improved tenderness. PAC200 increased (p<0.05) L* and protected (p<0.05) yellow pigments (b* values) of thigh meat from degradation compared with the CONT diet. At the end of the chilled storage period, BAR600 and PAC600 significantly reduced (p<0.06) MDA concentrations in breast meatballs compared to the CONT. The dietary supplementation of BAR and PAC improved (p<0.03) oxidative stability of thigh meatballs, except for BAR200. In conclusion, the dietary addition of BAR and PAC extracts may improve meat quality and prevent lipid oxidation in white and dark precooked and chilled chicken meatballs