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1. This study investigated the effects of hydroxy trace minerals (HTM) compared to sulphate trace minerals (STM) supplementation on growth performance, carcase parameters and mineral retention in broilers.2. A total of 1792 male Cobb 500 d-old were allocated in a completely randomised trial design to one of eight dietary treatments with eight replicates per treatment. The HTM sources used were two levels of Cu hydroxychloride (CHC) (low and high), combined with three levels of Zn hydroxychloride (ZHC) (low, med and high) and two additional treatments STM; Cu sulphate monohydrate (CSM) (low and high) combined with high Zn sulphate monohydrate (ZSM). At 21 and 42 d-old growth performance was evaluated. Additionally, at 42 d-old the carcase traits, meat quality, apparent ileal absorption and activity of antioxidant enzymes were accessed.3. A data showed that broilers receiving high-CHC had higher body weight, weight gain and better feed conversion ratio as compared to low-CHC at 21 d-old. On day 42, the feed conversion ratio was improved for birds supplemented with high-CHC in diets containing med-ZHC, as compared to low-CHC.4. Dietary Cu increased the redness of breast colour at the level of high-CHC compared to low-CHC. Greater results were observed on carcase traits for the med-ZHC group as compared to low- or high-ZHC. The ceruloplasmin activity in serum increased in the high-CSM diets containing high-ZSM as compared to low-CSM. The AIA of Cu was higher in broilers supplemented with high-CHC containing med-ZHC as compared to low-CHC. Otherwise, the AIA of Zn increased in broilers fed low-CHC containing low- or med-ZHC as compared to high-CHC.5. The trial showed that mineral trace supplementation of broilers diets with high-CHC (150 mg/kg) and low-ZHC (80 mg/kg) was a good alternative to replace sulphate mineral sources in diets.

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ABSTRACT The present study was conducted to evaluate the effects of phytogenic additives (PA) and organic acids (OA), alone or in combination, on the performance, intestinal histomorphometry and lipid oxidation, and immune responses of broiler chickens. In this experiment, 820 one-day-old chicks were distributed according to a completely randomized design in a 2 × 2 + 1 factorial arrangement, with four replicates of 41 broilers each. The dietary treatments consisted of a control diet with no PA or OA (CD); CD with OA and no PA (CD+OA-PA); CD with PA and no OA (CD+PA-CD); CDwith both PA and OA (CD+PA+CD); and CD + avilamycin + monesin sodium. Broiler performance was not affected by the alternative feed additives, except from 1 to 21 days, when broilers fed the CD or CD+PA+OA diets showed higher body weight gain than those fed the CD with only OA. The broilers fed the diet containing avilamycin and monensin presented better performance. The supplementation of PA and OA increased bursalcortical area on21 and 42 days post-hatch. On 21 days post-hatch, broilers fed the AGP diet presented higher ileal villus height than those fed the control diet. The pH values of the jejunum content were reduced on the OA-fed chickens. Higher villus height and crypt depth were found in the alternative additive-fed chickens on 7 days post-hatch. On 42 days post-hatch, the percentage of the bursal cortex increased in PA-fed broilers; however, there was no increase in antibody production. The PA-fed chickens presented lower thiobarbituric acid reactive substances (TBARS) values in the small intestine. The dietary supplementation of phytogenic additives, individually or in combination associated with organic acids, does not affect broiler live performance or intestinal histomorphometry; however, it enhances immune responses and intestinal quality.

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ABSTRACT The present study was conducted to evaluate the effects of phytogenic additives (PA) and organic acids (OA), alone or in combination, on the performance, intestinal histomorphometry and lipid oxidation, and immune responses of broiler chickens. In this experiment, 820 one-day-old chicks were distributed according to a completely randomized design in a 2 × 2 + 1 factorial arrangement, with four replicates of 41 broilers each. The dietary treatments consisted of a control diet with no PA or OA (CD); CD with OA and no PA (CD+OA-PA); CD with PA and no OA (CD+PA-CD); CDwith both PA and OA (CD+PA+CD); and CD + avilamycin + monesin sodium. Broiler performance was not affected by the alternative feed additives, except from 1 to 21 days, when broilers fed the CD or CD+PA+OA diets showed higher body weight gain than those fed the CD with only OA. The broilers fed the diet containing avilamycin and monensin presented better performance. The supplementation of PA and OA increased bursalcortical area on21 and 42 days post-hatch. On 21 days post-hatch, broilers fed the AGP diet presented higher ileal villus height than those fed the control diet. The pH values of the jejunum content were reduced on the OA-fed chickens. Higher villus height and crypt depth were found in the alternative additive-fed chickens on 7 days post-hatch. On 42 days post-hatch, the percentage of the bursal cortex increased in PA-fed broilers; however, there was no increase in antibody production. The PA-fed chickens presented lower thiobarbituric acid reactive substances (TBARS) values in the small intestine. The dietary supplementation of phytogenic additives, individually or in combination associated with organic acids, does not affect broiler live performance or intestinal histomorphometry; however, it enhances immune responses and intestinal quality.(AU)

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We aimed to study the behaviour of tissue renewal in blood, pectoral muscle and keel of fattening quails during their growth and adulthood through carbon-13 turnover using the stable isotope technique. Three hundred male European quails were randomly subjected to six treatments. Diets fed to animals were initially based on corn and soybean meal and were replaced at 0, 7, 14, 21, 28 and 35 days of age with diets of rice grits and soybean meal. These diets have distinct isotopic signals and over time it changes; the tissue will incorporate dietary signal, and then, we can measure the return time for each tissue in each age. Treatments were T1 (0 to 21 days), T2 (7 to 35 days), T3 (14 to 42 days), T4 (21 to 56 days), T5 (28 to 63 days) and T6 (35 to 70 days). Carbon-13 turnover in tissues of the birds at the above-mentioned time periods was calculated using the first-order exponential function. The values of half-lives were 2.6, 3.6, 5.4, 6.3, 9.0 and 9.8 days for blood and 2.0, 1.7, 4.8, 6.7, 6.9 and 6.6 days for pectoral muscle in treatments T1, T2, T3, T4, T5 and T6 respectively. The half-lives for the keel in treatments T2, T3, T4, T5 and T6 were 2.0, 5.4, 7.7, 8.9 and 15 days respectively. Thus, half-life in sampled tissues generally increased with age of birds. Initially, the tissue half-lives are influenced by growth, and at the end of the growth cycle, the breast muscle tissue was the most metabolically active in either periods, followed by blood and the keel. All tissues showed a sigmoidal growth curve, which can be confirmed by half-life as a function of age.

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The objective of this study was to evaluate the process of L-methionine incorporation in the blood plasma, liver, breast muscle, and abdominal fat of 35- to 59-d-old broiler chickens using the carbon stable isotope (12C and 13C) technique for the estimation of methionine requirements. In this experiment, 51 male broiler chickens orally received a solution of L-[13C1] methionine (92 atm % 13C) at 29 µmol/kg live weight/h for 6 h. Three birds were sacrificed for tissue collection at times 0 h (control), 0.5, 1, 2, 3, 4, 5, 6, 12, 24, 48, 72, 96, 120, 144, 168, and 336 h after the administration of the first dose. Tissue L-[13C1] methionine incorporation mass and percentage results were analyzed using Minitab 16 statistical software. Except for abdominal fat, tissue methionine levels gradually increased after the administration of the methionine solution. The calculated half-lives of methionine in the blood plasma, liver, and breast muscle were 2.52, 1.36, and 3.57 h, respectively, suggesting a greater rate of methionine incorporation in the liver, followed by blood plasma and breast muscle. The isotopic dilution showed that 2.81, 4.79, and 23.64% of the administered L-methionine were retained in the blood plasma, liver, and breast muscle, respectively. The methionine requirements of finisher broilers may be estimated using the carbon isotope technique, and approximately 3, 5, and 24% methionine is used for the synthesis of blood plasma, liver, and breast muscle, respectively, at the evaluated dose.(AU)

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The objective of this study was to evaluate the process of L-methionine incorporation in the blood plasma, liver, breast muscle, and abdominal fat of 35- to 59-d-old broiler chickens using the carbon stable isotope (12C and 13C) technique for the estimation of methionine requirements. In this experiment, 51 male broiler chickens orally received a solution of L-[13C1] methionine (92 atm % 13C) at 29 µmol/kg live weight/h for 6 h. Three birds were sacrificed for tissue collection at times 0 h (control), 0.5, 1, 2, 3, 4, 5, 6, 12, 24, 48, 72, 96, 120, 144, 168, and 336 h after the administration of the first dose. Tissue L-[13C1] methionine incorporation mass and percentage results were analyzed using Minitab 16 statistical software. Except for abdominal fat, tissue methionine levels gradually increased after the administration of the methionine solution. The calculated half-lives of methionine in the blood plasma, liver, and breast muscle were 2.52, 1.36, and 3.57 h, respectively, suggesting a greater rate of methionine incorporation in the liver, followed by blood plasma and breast muscle. The isotopic dilution showed that 2.81, 4.79, and 23.64% of the administered L-methionine were retained in the blood plasma, liver, and breast muscle, respectively. The methionine requirements of finisher broilers may be estimated using the carbon isotope technique, and approximately 3, 5, and 24% methionine is used for the synthesis of blood plasma, liver, and breast muscle, respectively, at the evaluated dose.

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The objective of this study was to determine if a diet supplemented simultaneously with vitamins C and E would alleviate the negative effects of heat stress, applied between 28 and 42 days of age, on performance, carcass and meat quality traits of broiler chickens. A total of 384 male broiler chickens were assigned to a completely randomized design, with a 2×3 factorial arrangement (diet with or without vitamin supplementation and two ambient temperatures plus a pair-feeding group) and 16 replicates. Chickens were kept in thermoneutral conditions up to 28 days of age. They were then housed in groups of four per cage, in three environmentally controlled chambers: two thermoneutral (22.5 and 22.6°C) and one for heat stress (32°C). Half the chickens were fed a diet supplemented with vitamins C (257 to 288 mg/kg) and E (93 to 109 mg/kg). In the thermoneutral chambers, half of the chickens were pair-fed to heat stressed chickens, receiving each day the average feed intake recorded in the heat stress chamber in the previous day. Meat physical quality analyses were performed on the pectoralis major muscle. No ambient temperature×diet supplementation interaction effects were detected on performance, carcass, or meat quality traits. The supplemented diet resulted in lower growth performance, attributed either to a carry-over effect of the lower initial BW, or to a possible catabolic effect of vitamins C and E when supplemented simultaneously at high levels. Heat stress reduced slaughter and carcass weights, average daily gain and feed intake, and increased feed conversion. Growth performance of pair-fed chickens was similar to that of heat stressed chickens. Exposure to heat stress increased carcass and abdominal fat percentages, but reduced breast, liver and heart percentages. Pair-fed chickens showed the lowest fat percentage and their breast percentage was similar to controls. Heat stress increased meat pH and negatively affected meat color and cooking loss. In pair-fed chickens, meat color was similar to the heat stressed group. Shear force was not influenced by heat stress, but pair-fed chickens showed the tenderest meat. In conclusion, reduction in growth performance and negative changes in meat color in heat stressed chickens were attributed to depression in feed intake, whereas negative changes in body composition, higher meat pH and cooking loss were credited to high ambient temperature per se. Diet supplementation with vitamins C and E as antioxidants did not mitigate any of these negative effects.

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The effects of the dietary substitution of dry corn by high-moisture corn grain silage (HMCGS) were evaluated on the performance, nutrient digestibility and serum biochemical parameters of broilers reared in an alternative production system and submitted to different environmental temperatures. A total of 288 one-day-old male Cobb chicks were distributed according to a randomized block design in a 3x4 factorial arrangement: three environmental temperatures (hot, thermoneutral or cold) and four levels of HMCGS in substitution of dry corn (0%, 20%, 40% or 60%). The acid analysis showed that the evaluated HMCGS contained average percentage values of ethanol, lactic acid, and acetic acid (expressed in 100% of dry matter) of 0.7690, 2.7320 and 0.0249%, respectively. Propionic and butyric acids were not detected. Dry corn and HMCGS presented pH values of 5.8 and 3.3, respectively. The inclusion of HMCGS reduced dietary pH, as shown by the values of 5.7, 5.4, 5.1 and 4.8 recorded for the diets containing 0%, 20%, 40% and 60% of HMCGS, respectively. There was no significant interaction between diets and environmental temperature. HMCGS may replace up to 40% dry corn in broiler diets when performance, triglyceride levels, and HDL-cholesterol ratio is considered, and up to 60% when nutrient digestibility is evaluated. High environmental temperature impairs broiler performance, nutrient digestibility, and serum biochemistry, demonstrating the influence of environmental temperature on broiler metabolism and performance.

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O estudo objetivou avaliar o turnover do 13C no sangue e plasma de codornas japonesas utilizando a técnica de isótopos estáveis, para a obtenção do patamar de equilíbrio isotópico que servirá de fundamento para estudos de rastreabilidade. Foram utilizadas 300 aves durante o período experimental de 1-42 e 49-97 dias de idade. Os tratamentos da primeira fase foram constituídos de dietas à base de arroz (C3), contendo ou não farinha de carne e ossos bovinos e um com dieta à base de milho (C4). Nessa primeira fase foi analisado o turnover do sinal isotópico do matrizeiro à base de dietas C4 para dietas à base de C3, como também as diferenças isotópicas das dietas contendo ou não farinha de origem animal. Na segunda fase houve uma substituição de dietas, ou seja, as aves no tratamento C4 da primeira fase passaram a consumir dieta C3, e o tratamento que antes consumia dieta C3 passou para dieta C4. Para determinar a taxa de turnover e o percentual estimado de participação da farinha na composição do material coletado, foi empregado o modelo de diluição isotópica utilizando valores do δ13C. A comparação entre as meias-vidas do sangue e plasma da primeira fase revelou o enriquecimento do δ13C na dieta; já na segunda fase foi possível observar as velocidades de incorporação após a troca das dietas.(AU)

The study aimed to evaluate the turnover of 13C in the blood and plasma of Japanese quail using the technique of stable isotopes to obtain the level of isotopic equilibrium that will be the foundation for studies of traceability. A total of 300 birds during the experimental period of 1-42 and 49-97 days of age. The first phase of the treatments consisted of diets based on rice (C3), with or without meat and beef bones and a diet based on corn (C4). This was first examined the turnover signal farm matrix isotope-based diets based diets C4 to C3, as well as isotopic differences of diets with or without animal meal In the second stage there was a substitution of diets, or C4 treatment of the first stage passes to consume C3-based diet than before treatment and diet consumed C3 to C4 diet. To determine the turnover rate and the estimated percentage of participation of flour in the composition of the collected material was used isotope dilution model using δ13C values. A comparison of the half-lives of blood and plasma from the first phase discloses the enrichment of dietary δ 13C, in the second phase was observed after incorporation speeds exchange diets.(AU)

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The effects of the dietary substitution of dry corn by high-moisture corn grain silage (HMCGS) were evaluated on the performance, nutrient digestibility and serum biochemical parameters of broilers reared in an alternative production system and submitted to different environmental temperatures. A total of 288 one-day-old male Cobb chicks were distributed according to a randomized block design in a 3x4 factorial arrangement: three environmental temperatures (hot, thermoneutral or cold) and four levels of HMCGS in substitution of dry corn (0%, 20%, 40% or 60%). The acid analysis showed that the evaluated HMCGS contained average percentage values of ethanol, lactic acid, and acetic acid (expressed in 100% of dry matter) of 0.7690, 2.7320 and 0.0249%, respectively. Propionic and butyric acids were not detected. Dry corn and HMCGS presented pH values of 5.8 and 3.3, respectively. The inclusion of HMCGS reduced dietary pH, as shown by the values of 5.7, 5.4, 5.1 and 4.8 recorded for the diets containing 0%, 20%, 40% and 60% of HMCGS, respectively. There was no significant interaction between diets and environmental temperature. HMCGS may replace up to 40% dry corn in broiler diets when performance, triglyceride levels, and HDL-cholesterol ratio is considered, and up to 60% when nutrient digestibility is evaluated. High environmental temperature impairs broiler performance, nutrient digestibility, and serum biochemistry, demonstrating the influence of environmental temperature on broiler metabolism and performance.(AU)

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