ABSTRACT. Two experiments were carried out to evaluate the effects of protease addition to the diet of broilers at a higher level (1× or 2×) than the nutritional value proposed for the enzyme. The first experiment, 1280 day-old chicks (Cobb500®) were randomly allocated (randomized block design, 2×2+1 factorial arrangement), five treatments, eight replicates containing 32 birds/replicate. Treatments consisted: control diet without protease (CD); CD + 1× nutritional value of the enzyme (CDM1); CD + 2× nutritional value of the enzyme (CDM2); CDM1 + protease; and CDM2 + protease. The experimental period was 42 days. The mean weight (AFW), feed intake (FI), weight gain (WG), feed conversion, and carcass yield were evaluated. Significant differences were observed for AFW, WG, FI, abdominal fat yield, and feet percentage in the carcass. In the second experiment, 120 Cobb500® chicks at 14 days of age were allotted in a completely randomized design, 2×2+1 factorial arrangement, five treatments, six replicates with four birds/replicate. The treatments were consistent with the first experiment. Significant improvements in the nitrogen balance were observed for the broilers that received protease. The use of the enzyme tested is recommended with the recommended nutritional matrix, improving the zootechnical indices of broilers.

ABSTRACT. An experiment was conducted to evaluate the effect of diets with reduced energy level content, supplemented with carbohydrase, on broiler performance and the coefficient of metabolizability of nutrients. A total of 720 one-day-old male Cobb-500 chicks were distributed in a completely randomized design, with six treatments, eight repetitions of 15 birds each. The treatments were: (1) a positive control, basal diet to meet the requirements of broiler chickens (PC); (2) a negative control, basal diet with a reduction of 80 kcal kg-1 (NC); (3) NC + alphagalactosydase; (4) NC + xylanase; (5) NC + xylanase and alphagalactosydase, and (6) NC + enzymatic blend (alphagalactosydase, xylanase, pectinase and amylase). The nutrient digestibility was not improved by use of enzymes. At 7 days of age, the broilers which were fed diets supplemented with enzymes showed a lower feed intake (FI) and better feed conversion ratio (FCR) than the broilers fed on PC. Both the NC and enzymatic blend resulted in a worse performance of the broilers at 21, 35 and 42 days old. The use of alphagalactosydase and xylanase, isolated or in combination, in a corn-soybean meal-based diet is effective in improving the growth performance of broilers fed energy-reduced diets.

Abstract The aim of this study was to examine the influence of the specific gravity of maize kernels on physicochemical traits, energy values, and metabolizability coefficients. Pearson’s correlations were evaluated between specific gravity (kg/m3) and crude protein (%); ether extract (%); crude fiber (%); gross energy (%); presence of fumonisins (ppb) and aflatoxins (ppb); and kernel quality (good, rotten, weevil-damaged, broken, and shriveled kernels, %). A metabolism trial was conducted with diets containing maize fractions of different specific gravities for male broilers from 14 to 21 days of age. Apparent metabolizable energy (AME), nitrogen-corrected AME (AMEn), and the metabolizability coefficients of dry matter (MCDM), crude protein (MCCP), ether extract (MCEE), calcium (MCCa), and phosphorus (MCP) were evaluated. The experiment consisted of five treatments (reference diet and diets with 40% replaced with maize at five specific gravities (740, 740, 760, or 800 kg/m3). Eight replications were used, totaling 400 broilers chickens. The Scott-Knott test was applied and regression equations were fitted to compare the treatments. Specific gravity had moderate correlations with good and broken kernels and low-magnitude correlations with chemical parameters. Increasing specific gravities caused AME and AMEn to increase linearly when analyzed on an as-is basis; and to respond quadratically when expressed on a dry-matter basis. The specific gravity of 780 kg/m3 provided the lowest MCDM, MCCP, MCCa, and MCP values, whereas the lowest MCEE, was found at the lowest density. It was not possible to determine the best nutritional composition or the best metabolizability coefficients.

Resumo Objetivou-se avaliar a influência da densidade do grão de milho sobre características físico-químicas, valores energéticos e de metabolizabilidade aparente. Avaliou-se a correlação entre a densidade específica (kg/m3) e os parâmetros: proteína bruta (%); extrato etéreo (%); fibra bruta (%); energia bruta (%); presença de fumonisinas (ppb) e aflatoxinas (ppb); umidade (%); grãos bons, quebrados, chochos, carunchados e ardidos, em Percentagem. Um ensaio de metabolismo com dietas contendo diferentes densidades específicas do grão de milho, para frango de corte, no período de 14 a 21 dias de idade, foi conduzido para avaliar a energia metabolizável aparente (EMA) e a corrigida pelo balanço de nitrogênio (EMAn), os coeficientes de metabolizabilidade: matéria seca (CM_MS), proteína bruta (CM_PB), extrato etéreo (CM_EE), cálcio (CM_Ca) e fósforo (CM_P). O experimento foi composto por cinco tratamentos (dieta referência e dietas substituindo 40% desta com milhos de densidades específicas: 740 kg/m3, 760 kg/m3, 780 kg/m3 e 800 kg/m3), com oito repetições, totalizando 400 frangos machos. As médias foram comparadas pelo teste de Scott-knott e estimada as equações de regressão nas diferentes densidades específicas das frações de milho. As correlações entre a densidade específica e grãos bons e quebrados foram de moderada magnitude e com os parâmetros químicos foram de baixa magnitude. Com o aumento da densidade específica para EMA e EMAn na matéria natural obteve-se resposta linear decrescente, enquanto na matéria seca, foi quadrático. Para CMMS, CMPB, CMCA e CMP a densidade de 780 kg/m3 apresentou os menores valores, enquanto para CMEE, o menor valor foi para a menor densidade específica. Não foi possível determinar a fração de milho com melhor composição nutricional e melhores coeficientes de metabolizabilidade.

Abstract This study aimed to evaluate the effect of including soy lecithin emulsifier (SL) in broiler diets with reduced metabolizable energy levels and to correlate it with nutrient metabolizability coefficients, as well as to determine apparent metabolizable energy (AME). Two metabolic trials were conducted in a completely randomized design with a 3x2 factorial arrangement (diet with three levels of metabolizable energy, with or without the inclusion of emulsifier), totaling six treatments. In the starter phase, chicks received diets with 2,950, 3,050, and 3,150 kcal/kg of metabolizable energy, with six replications of 10 birds each, totaling 360 birds. In the grower phase, the energy levels of 3,100, 3,150, and 3,200 kcal/kg of feed were tested in 210 birds were used in seven replications of five chicks each. An interaction effect was observed in the starter phase, with the nitrogen metabolizability coefficient increasing when the emulsifier was added to diets with reduced energy. Additionally, emulsifier inclusion increased nitrogen-corrected AME (AMEn). An interaction effect was also present in the grower phase, with AME and AMEn increasing when the emulsifier was added to diets with lower energy levels. In summary, emulsifier inclusion in broiler diets can reduce metabolizable energy while improving AMEn in both the starter and grower phases, as well as AME in growing broilers.

Resumo Objetivou-se avaliar a adição do emulsificante, lecitina de soja, nas rações de frangos com redução dos níveis de energia metabolizável e correlacioná-las com os coeficientes de metabolizabilidade de nutrientes, além da determinação da energia metabolizável aparente (EMA). Realizou-se dois ensaios metabólicos em delineamento inteiramente casualizados, esquema fatorial 3x2 (ração com três níveis de energia metabolizável, com ou sem a inclusão do emulsificante na dieta), totalizando seis tratamentos. Na fase inicial, os pintos receberam dieta com 2.950, 3.050 e 3.150 kcal/kg de energia metabolizável, com seis repetições com 10 aves, totalizando 360 aves. Na fase de crescimento foram utilizadas 210 aves, sendo sete repetições com cinco frangos e os níveis de energia testados foram: 3.100, 3.150 e 3.200 kcal/kg de ração. Na fase inicial, observou-se efeito de interação, apresentando aumento do coeficiente de metabolizabilidade do nitrogênio (CMN) ao adicionar o emulsificante em dietas com energia reduzida e também, efeito do emulsificante no aumento da energia metabolizável aparente corrigida pelo balanço do nitrogênio (EMAn). Na fase de crescimento, observou-se efeito de interação, apresentando aumento da EMA e EMAn ao adicionar o emulsificante em dietas com menores níveis de energia. Conclui-se que a inclusão do emulsificante é indicada para frangos de corte, pois permite reduzir a energia metabolizável da dieta, melhorando a EMAn nas fases inicial e de crescimento, bem como a da EMA com frangos em crescimento.

ABSTRACT The objective of this study was to evaluate the effects of replacing choline chloride with a plant source of choline on the locomotor system, liver health, and development of breast myopathies in broilers aged 1-42 days of age. We allocated 1,120 one-day-old Cobb broilers to four treatment groups and fed them commercial diets based on corn and soybean meal. The treatments included choline in the form of 1,800.00 mg/kg choline chloride; 1,350.00 mg/kg choline chloride + 450.00 mg/kg herbal choline; 900.00 mg/kg choline chloride + 900.00 mg/kg herbal choline; and 1,000.00 mg/kg herbal choline. Each treatment group had eight replications. Throughout the experiment, gait score, footpad dermatitis, hock burn, and leg deformities (valgus and varus) were evaluated in the birds at 28 and 35 days of age. After slaughter, parameters such as breast myopathies, tibial dyschondroplasia score, and histological slides of the pectoral muscle, liver, and proximal tibial epiphysis were assessed. The results demonstrated good hepatic and locomotor health in the broilers, as no classical signs of choline deficiency were observed. Statistical analyses indicated no significant differences between treatments in terms of liver and locomotor health, suggesting that broilers fed diets supplemented with the plant source did not experience choline deficiency. Additionally, no statistically significant differences were found between treatments regarding breast myopathies. Overall, the tested choline plant source can effectively replace choline chloride in broiler diets.

RESUMO: Objetivou-se avaliar o comportamento de pintainhas de postura na fase de cria, alimentadas com dietas formuladas com aumento de fibra bruta e dois alimentos com composições de fibra diferentes. O trabalho foi realizado na Universidade Federal de Goiás, Goiânia, GO, utilizando-se 300 pintainhas Bovans White, em delineamento inteiramente casualizado e arranjo fatorial 2x2+1, com dois níveis de fibra bruta na dieta (3,0% e 3,5 % de FB), duas fontes de fibra (farelo de trigo e bagaço de cana) e o tratamento testemunha (ração a base de milho e farelo de soja), totalizando cinco tratamentos e seis repetições de 10 aves cada. Foram avaliados padrões de comportamento de manutenção e bem-estar aos 21 e 42 dias de idade. Não houve diferença no comportamento e na classificação por ordem de importância das atividades realizadas pelas aves alimentadas com fibra e observadas aos 21 e 42 dias pelo teste de Kruskal Wallis (P>0,05). Obteve-se condições média e boa com farelo de trigo e 3,5 e 3,0% de fibra bruta, respectivamente, com 21 dias de idade. Aos 42 dias, o uso de bagaço de cana ao nível de 3,5% de fibra bruta e o farelo de trigo ao nível de 3,0%, mostraram boas condições de comportamento. A utilização de fibra bruta na alimentação de frangas não alterou o comportamento das aves.

ABSTRACT: This study evaluated the behavior and welfare conditions of laying chicks in the starter phase, fed with diets formulated with increasing levels of crude fiber (CF) and two feedstuffs with different fiber compositions. The experiment was developed at the Federal University of Goiás, in Goiânia - GO, Brazil. Three hundred Bovans White chicks were evaluated in a completely randomized design with a 2×2+1 factorial arrangement corresponding to two levels of CF in the diet (3.0 and 3.5%) and two fiber sources (wheat bran and sugarcane bagasse), plus a control treatment (maize- and soybean meal-based), totaling five treatments with six replicates of 10 birds each. Maintenance behavioral patterns and welfare were assessed at 21 and 42 days of age. There was no difference in behavior and classification by order of importance of the activities performed by the fiber-fed birds observed at 21 and 42 days, according to the Kruskal Wallis test (P>0.05). Medium and good welfare conditions were obtained with wheat bran at 3.5 and 3.0% CF, respectively, at 21 days of age. At 42 days, the use of sugarcane bagasse at the CF level of 3.5% and wheat bran at the level of 3.0%provided good behavior conditions. The use of crude fiber in the feeding of hens did not change their behavior.

ABSTRACT The objective of this study was to determine the effects that breeder age has on digestive and immune system development; the transfer of immunoglobulins to egg yolk, yolk sac, and neonate chicks; and the immune response of chicks up to 35 days old. Three ages (32, 42, and 52 weeks) of Hubbard breeders were studied with ages as treatments. A total of 425 eggs were weighed for each of the three treatments and incubated. After hatching, a total of 300 1-day-old chicks were used in each treatment. We studied the development of the gastrointestinal tract and immune system of progeny and IgY transfer from breeder to progeny. Chicks from 52-week-old breeders had greater gastrointestinal tract growth up to seven days of life and greater body weight at 14 days. Older breeders (52 weeks) had higher amounts of IgY in serum and egg yolk. Chicks from the youngest breeders (32-weeks-old) had a better immune response at two weeks post-vaccination. It can be concluded that the older breeders have a greater capacity to immunize progeny up to 14 days. Strategies can be developed to increase IgY in the serum of young breeders and, consequently, increase the innate immunity of the newly-hatched chicks.

Resumo Uma das pragas que mais afetam e comprometem a produção avícola no mundo é o inseto Alphitobius diaperinus, conhecido como cascudinho. Este inseto é vetor de doenças que comprometem não só a produção de frangos como também a saúde humana. Objetivou-se com esse trabalho avaliar a eficácia e determinar a dose adequada de Metilxantina (MTX), inseticida natural extraído da cafeína, para o controle da população adulta de cascudinhos em cama de frango. Foram utilizados 2.500 cascudinhos adultos distribuídos em delineamento inteiramente casualizado, cinco tratamentos, 10 repetições com 50 insetos por repetição. Os tratamentos consistiram de grupo controle e quatro concentrações 14 g/m2, 16 g/m2, 18 g/m2, 20 g/m2 de MTX espalhadas em recipientes plásticos contendo cama de frango reutilizada e ração, alocados em um galpão de frangos de corte a fm de simular a condição de granja. Período experimental foi de 18 dias e realizadas cinco leituras nos dias dois, quatro, seis, 10 e 18. A MTX afetou (P<0,05) a taxa de mortalidade acumulada de cascudinhos, grupos de insetos alojados em caixas tratadas com 16 g/m2 de MTX apresentaram maior mortalidade acumulada (86,6%) ao final do período experimental. Conclui-se que MTX tem ação inseticida sobre adultos de cascudinho, podendo ser utilizada sobre a cama de frango para o controle da população deste inseto em galpões de criação de frangos, a concentração 16 g/MTX/m2 demonstrou maior efetividade.

Abstract One of the pests that most affect and compromise poultry production worldwide is the insect Alphitobius diaperinus, known as the lesser mealworm. This insect is a vector of diseases that compromise not only chicken production but also human health. This study proposes to examine the efficacy and determine the appropriate rate of methylxanthine (MTX), a natural insecticide extracted from cafeine, for the control of an adult population of lesser mealworms in poultry litter. A total of 2,500 adult mealworms were distributed into five treatments in a completely randomized design using 10 replications with 50 insects per replication. The treatments consisted of a control group and four concentrations of MTX (14, 16, 18, and 20 g/m2) spread in plastic boxes containing reused poultry litter and feed, allocated in a broiler shed, to simulate the farm condition. The experimental period was 18 days, and five readings were performed on days 2, 4, 6, 10, and 18. Methylxanthine affected (P<0.05) the mealworms’ cumulative mortality rate, with the groups of insects housed in boxes treated with 16 g /m2 MTX showing the highest cumulative mortality (86.6%) at the end of the experimental period. In conclusion, MTX has insecticidal action on adults of lesser mealworm and can be used on chicken litter to control the population of this insect in poultry sheds. The MTX concentration of 16 g/m2 showed the greatest effectiveness.

Resumo Os ovos são usados como ingredientes da indústria alimentícia devido às suas propriedades funcionais. Ovos de diferentes espécies de aves podem ser usados no processamento industrial. Foram realizados experimentos reológicos em estado estacionário para obtenção das curvas de fluxo e também em estado dinâmico para estudar as propriedades reológicas dos ovos de emas Rhea americana. O comportamento viscoelástico dos fluidos em função das temperaturas de coagulação para albúmen e gema e da frequência oscilatória foi estudado. Foram analisados 15 ovos de rhea armazenados por até 28 dias a 10 °C em 1, 7, 14, 21 e 28 dias. As frações de albumina e gema mostraram comportamento reológico pseudoplástico com pequeno cisalhamento de fluxo inicial e dependência do tempo de cisalhamento, com albúmen demonstrando tixotropia e a gema mostrando reopexia. Em testes reológicos de cisalhamento baixo, observou-se gelificação térmica de albúmen, apresentando uma primeira mudança no módulo elástico em torno de 56 °C, e um segundo de 78 °C. Na gema, observou-se uma mudança a partir de 66 °C, com variações mais estruturais no desenvolvimento do gel a temperaturas mais elevadas. Para os ovos de rhea, a temperatura estruturante de gel (gelificação) de albumen (80 °C) e gema de ovo (69 °C) não sofreu variações durante os períodos de armazenamento. Em comparação com os ovos comerciais, as maiores temperaturas de viscosidade e gelificação apresentadas pelos ovos rhea podem ajudar a determinar o tamanho do sistema de processamento industrial, pois podem ser submetidos a temperaturas mais altas sem modificar estruturas proteicas e dificultar o processo.

Abstract Eggs are used as food industry ingredients due to their functional properties. Eggs from different bird species are used in industrial processing; therefore, rheological experiments were carried out at steady state to obtain the flow curves and also at a dynamic state to study the rheological properties of greater rhea eggs. The viscoelastic behavior of the fluids as a function of the coagulation temperatures for albumen and yolk and of the oscillatory shear frequency was studied. Fifteen rhea eggs stored for up to 28 days at 10 °C were analyzed at 1, 7, 14, 21, and 28 days. The albumen and yolk fractions showed pseudoplastic rheological behavior with small initial flow shear and dependence on shear time, with albumen demonstrating thixotropy and the yolk showing rheopexy. In low shear rheological tests, thermal gelation of albumen was observed, presenting a first change in the elastic modulus around 56 °C, and a second from 78 °C. In the yolk, a change was observed from 66 °C, with more structural variations in the development of the gel at higher temperatures. For rhea eggs, the gel structuring (gelation) temperature of albumen (80 °C) and egg yolk (69 °C) did not undergo variations during the storage periods. Compared to commercial eggs, the higher viscosity and gelation temperatures presented by the rhea eggs can help determine the size of the industrial processing system as they can be submitted to higher temperatures without modifying protein structures and hindering the process.

ABSTRACT The objective of this study was to evaluate the effects of guava extract standardized in phenolic compounds (SGE) on broiler performance, nutrient digestibility, and intestinal histomorphometry. A total of 300 one-day-old male Cobb-500® broiler chicks were distributed in a completely randomized design with five treatments (basal diet supplemented with 120 mg vitamin E/kg and basal diet supplemented with 0, 600, 800, or 1,000 mg SGE/kg) and six replicates of ten birds each. Performance was evaluated at seven and 21 days of age; digestibility of nutrients was determined by total excreta collection from 18 to 21 days of age; and histomorphometry of the small intestine was assessed at 21 days of age. Broilers fed diets supplemented with SGE or vitamin E had higher body weight and weight gain and better feed conversion than those fed unsupplemented diet at seven days of age. At the same age, there was a quadratic effect of SGE levels on body weight and weight gain, with better weights for 715 and 716 mg SGE/kg, respectively; and a decreasing linear effect for feed conversion. At 21 days of age, body weight and weight gain increased linearly with the inclusion of SGE in diet. Digestibility of feed nutrients was not influenced by treatments. Broilers fed diet supplemented with 800 or 1,000 mg SGE/kg had greater villus height and villus:crypt ratio of the duodenum than those fed unsupplemented diet. Villus height in the jejunum of broilers fed diet supplemented with 600 mg SGE/kg was lower than that of broilers that received vitamin E. Guava extract standardized in phenolic compounds can be used in diets for broilers in the starter phase, considering that the extract increases weight gain, reduces feed conversion, and helps in the development of the intestinal mucosa.

ABSTRACT Two experiments were carried out to evaluate the effects of digestible valine supplementation in pre-starter and starter diets on the productivity, nutrient metabolizability coefficient (NMC), and immune response of broilers from breeders of different ages. Experiments I and II were conducted with broilers in the pre-starter (1 to 7 days of age) and starter (8 to 21 days of age) phases, respectively. Broilers were fed diets that differed in their digestible valine content. In each trial, 400 male Cobb 500® chicks were randomly housed in a 2 × 4 factorial arrangement with eight treatments and five replicates of 10 birds each. The main effects were breeder age (37 vs. 52 weeks) and the digestible valine level in pre-starter (9.2, 10.2, 11.2, and 12.2 g/kg) and starter (8.3, 9.3, 10.3, and 11.3 g/kg) diets. Productive performance, intestinal histology, and immune response of broilers were evaluated. Supplementation with 11.2 g/kg valine in pre-starter diets improved NMC and increased villus height and villus:crypt ratio in the duodenum, jejunum development, and lymphocyte proliferation in the spleen of broilers at seven days of age, without improving performance (body weight gain, feed intake, and feed conversion ratio). In the starter phase, valine supplementation reduced feed intake but did not affect NMC, intestinal development, or immune response. The present results suggest that the same level of digestible valine should be used in the diet of broilers born to breeders of different ages, and the use of 9.2 and 8.3 g/kg digestible valine in pre-starter and starter diets, respectively, is sufficient to ensure satisfactory broiler performance. However, to improve the duodenum and jejunum development and immune response of broilers in the pre-starter phase, higher digestible valine levels are required.

ABSTRACT An experiment was conducted aiming to evaluate the effect of different levels of crude protein, based on the ideal protein concept and two rearing systems, on productive performance of brown laying hens. A total of 400 Hisex Brown laying hens between 30 and 45 weeks of age were distributed in a completely randomized design and a 2×4 factorial arrangement, with main effects including two rearing systems (cage and floor) and levels of crude protein (140, 150, 160, and 180 g kg−1), totalizing eight treatments. Five replicates with 10 birds each were used per experimental unit. The following parameters were evaluated: egg production, feed intake, body weight gain, feed conversion ratio, and quality traits such as dirty, cracked, or broken eggs. No interaction effect was observed between dietary protein levels and rearing systems for body weight gain, feed intake, egg production, egg weight, and feed conversion ratio. Feed intake and egg production were higher in the floor rearing system. Feed conversion ratio (kg/dz) was improved in birds reared in the cage system. The rate of cracked and broken eggs was higher in the cage system. The layers reared in the floor system produced a higher percentage of dirty eggs. The dietary protein level did not affect the evaluated parameters. Thus, we conclude that a floor rearing system is an option for layers, and the dietary protein level can be reduced up to 140 g kg−1 for Hisex Brown hens from 30 to 45 weeks of age.

ABSTRACT The objective of this study was to evaluate the inclusion of feather and blood meal (FBM) in broiler pre-starter and starter diets according to the processing method used. Performance, digestibility, and intestinal morphometry of broilers fed diets containing FBM were evaluated in two experiments, in the pre-starter (1-7 d) and starter (8-21 d) phases in a randomized block design with four treatments and five replicates of 12 birds, totaling 20 experimental units per trial. The criteria used for block formation was the battery floor. The meal was processed under different degrees of hydrolysis pressure (2.0 kgf/cm2 for 40 min; 2.5 kgf/cm2 for 30 min; and 3.0 kgf/cm2 for 20 min) and added at 9% to the pre-starter (Experiment I) and starter (Experiment II) diets. In each experiment, 480 male Cobb 500® chicks were allocated to batteries. The following variables were measured: live weight, weight gain, feed intake, feed conversion ratio, and digestibility and retention of dry matter, nitrogen, and ether extract. Performance was not influenced by the dietary inclusion of the ingredient. However, FBM subjected to the highest hydrolysis pressure resulted in the worst overall nutritional balances. The chickens were more susceptible to FBM processing in the pre-starter phase, when the hydrolysis pressure of 2.5 kgf/m2 for 30 min provided the best results. In the starter diet, FBM processed at a hydrolysis pressure of 2.0 kgf/m2 for 40 min provided the best performance results up to 14 days of age, without changing nutrient metabolism. Up to 9% feather and blood meal can be included in broiler pre-starter and starter diets as long as the ingredient processing method is well-known.

RESUMO: Teve-se como objetivos neste estudo avaliar o efeito dos níveis de metionina + cistina (Met+Cis) digestível na dieta sobre os parâmetros hematológicos e bioquímicos séricos de frangos de corte na fase inicial e de crescimento. Para isso, utilizou-se 1.800 pintos, machos, da linhagem Coob 500, sendo 900 pintos para a fase inicial (1 a 21 dias de idade) e mais 900 pintos para a fase de crescimento (22 a 42 dias de idade), distribuídos em delineamento inteiramente casualizado composto de cinco tratamentos, com seis repetições de 30 aves. Os tratamentos consistiram em 0,545; 0,616; 0,711; 0,782 e 0,853% e 0,514; 0,571; 0,647; 0,704 e 0,761% de Met+Cis digestíveis para a fase inicial e de crescimento, respectivamente. Os resultados demonstraram que níveis de Met+Cis digestível na alimentação de frango de corte, acarretam alterações em parâmetros hematológicos como: hemácia, hematócrito, hemoglobina, leucócitos totais, relação heterófilo: linfócito; e bioquímico sérico como: ácido úrico, albumina, colesterol total, proteínas séricas totais (PST), lipoproteína de baixa densidade (LDL) e triglicerídeos (TG). Os níveis digestíveis de Met + Cys na dieta de frangos de corte afetam os parâmetros hematológicos e a bioquímica sérica, principalmente em níveis mais elevados. A partir do nível de inclusão 0.761 de Met + Cist na dieta de frangos de corte, começam a aparecer alterações nos glóbulos vermelhos, hemoglobina e hematócrito.

ABSTRACT: The objective of this study was to evaluate the effect of digestible methionine and cystine (Met + Cys) levels on the hematological and serum biochemical parameters of broiler chickens during the initial and growth stages. For this, 1,800 male chicks of the Coob 500 strain were used, with 900 chicks in the initial phase (1 to 21 days old) and 900 chicks in the growth phase (22 to 42 days old), distributed in a completely randomized design of five treatments with six replicates of 30 birds. The treatments consisted of 0.545, 0.616, 0.711, 0.782, and 0.853%; and 0.514, 0.571, 0.647, 0.704, and 0.761% digestible Met + Cys for “1 to 21” and “22 to 42” days of breeding, respectively. Results showed that digestible Met + Cys levels in broiler feed altered some hematological parameters (erythrocyte, hematocrit hemoglobin, total leukocytes, heterophile: lymphocyte) and serum biochemistry (uric acid, PST, total LDL, and TG). The digestible Met + Cys levels in the diet of broilers affected the hematological parameters and serum biochemistry, especially at higher levels. From the inclusion level 0.761 of Met + Cist in the broiler diet, red blood cells, hemoglobin and hematocrit changes begin to appear.

ABSTRACT We aimed to evaluate the performance, nutrient digestibility, and intestinal histomorphometry of broilers fed diet supplemented with chondroitin sulfate and glucosamine sulfate. The experiment was carried out with 320 male broiler chicks distributed in a completely randomized design in a 2×2 factorial scheme (0 and 0.1% chondroitin sulfate and 0 and 0.3% glucosamine sulfate), with eight replications of 10 birds. Performance was evaluated at 7 and 21 days of age, nutrient digestibility of the diet was performed from 18 to 21 days of age, and small intestine histomorphometry was evaluated at 21 days of age. Broilers fed diet supplemented with 0.3% glucosamine sulfate showed high final weight and weight gain. A significant interaction was observed between sulfates for digestibility coefficients of nitrogen, mineral matter, and calcium. The use of 0.1% chondroitin sulfate without glucosamine sulfate resulted in a reduced digestibility of nitrogen but increased digestibility of total minerals and calcium. Diets without chondroitin sulfate with 0.3% glucosamine sulfate increased the digestibility coefficients of mineral matter and calcium. A significant interaction was found for jejunum villus height, which was higher in broilers fed diet supplemented with 0.3% glucosamine sulfate, regardless of the inclusion of chondroitin sulfate. Thus, supplementation with glucosamine sulfate in broiler diets contributes to high weight gain and villus height. Sulfates used in isolation promote high digestibility of minerals.