Point-of-care blood analyzers measure the nutritional state of eighteen free-living bird species.

Point-of-care devices offer the potential to democratize a suite of physiological endpoints and assess the nutritional state of wild animals through plasma metabolite profiling. Measurements of plasma metabolites typically occur on frozen tissue in the laboratory, thus dissociating measurements from field observations. Point-of-care devices, widely used in veterinary and human medicine, provide rapid results (seconds or minutes) allowing in situ measurements of wild animals in remote areas without the need for access to freezers. Using point-of-care devices, we measured glucose, triglyceride, cholesterol and ß-hydroxybutyrate levels in plasma from 18 wild bird species spanning nine families and three orders. The values from six different point-of-care devices correlated strongly with one another, and with traditional laboratory measurements from stored plasma (R2 = 0.70-0.90). Although POC devices provided accurate relative values in wild birds, absolute values varied from laboratory measurements by up to 50% illustrating the need for calibration equations. Furthermore, three case studies showed the potential for point-of-care devices at research stations where participants do not have access to a lab and sample preservation is difficult: (i) at a remote seabird colony, birds that were provided with supplemental food had higher levels of glucose and lower ß-hydroxybutyrate and cholesterol levels than unfed birds, suggesting they were in a better nutritional state; (ii) at a migration monitoring station, levels of triglycerides of two migratory songbirds increased with time of day, implying that they were fattening during stopover; and (iii) for diving seabirds, individuals that worked harder (shorter surface intervals) had higher glucose and lower ß-hydroxybutyrate implying that nutritional state is an index of foraging effort and success. We demonstrate that point-of-care devices, once validated, can provide accurate measurements of the nutritional state of wild birds. Such real-time measurements can aid in ecological research and monitoring, care of wildlife at rehabilitation centres, and in veterinary medicine of exotics.

Multivariate analysis of sources of polyunsaturated fatty acids, selenium, and chromium on the productive performance of second-cycle laying hens

An experiment was conducted to evaluate the effect of the intake of a mixture of fish and sacha inchi oils (iOM), organic selenium (iSe), and organic chromium (iCr) on egg production (EP) and feed conversion ratio (FCR) of Isa Brown second-cycle laying hens (SCLH) for 16 weeks (91-106 weeks old). Egg production and FCR were evaluated using multivariate models that included conventional equations and artificial neural networks (ANN) to study multiple nutritional interactions as alternatives to univariate dose-response models. Based on the best models, iOM, iSe, and iCr levels were optimized, and a global sensitivity analysis was implemented to quantify their influence on EP and FCR. The modified logistic model was selected as the best strategy to represent EP. In the case of FCR, an ANN model with a feed-forward architecture and softmax transfer function was selected as the best alternative. One of the scenarios to simultaneously optimize EP (89.1%) and FCR (1.94 kg feed/kg egg) at 16 weeks of production was established with 3.3 g/hen·day of iOM, 0.132 mg/ hen·day of iSe, and 0.176 mg/hen·day of iCr. However, optimization considering only FCR results in much lower optimal iCr levels (between 0.083 and 0.105 mg/hen·day) with a slight decrease in EP (87.9%). The global sensitivity analysis showed that iSe is an essential factor associated with the increase in EP, and iCr is the most influential factor for the decrease in FCR. When both criteria were taken into account simultaneously from a desirability function, iSe was the most critical factor.(AU)

Superdosing Phytases in the Diets of Light Laying Hens: Productive Performance and Bone Quality

Two experiments were carried out with the objective of evaluating the effect of superdosing of two phytases on performance, egg quality, digestive organ biometry and bone quality of light hens in the first (58 weeks) and second (87 weeks) productive cycle. In the first cycle, 270 light hens were used, in which a completely randomized design was adopted in a 2 x 2 + 1 factorial scheme (bacterial phytase or fungal phytase x 450 FTUs or 900 FTUs + control diet). In the second cycle, 270 hens were used, following the same design as the previous experiment. The performance and quality of the eggs were evaluated in both cycles, and the biometry of the digestive organs and bone characteristics were also evaluated in the first experiment. There was no effect in the comparison between the means for the performance and egg quality (in both experiments), or for the biometric variables and bone characteristics (first experiment). There was no significant interaction between the factors for any of the variables in the two experiments. In the first experiment, egg production was higher with bacterial phytase and egg weight with fungal phytase. The mineral matter showed greater value with 450 FTUs. It is recommended to use bacterial phytase produced from Escherichia coli as it improves the performance of light laying hens. The dosage of 450 FTUs improves the mineral content of light laying hens and the use of phytase in the laying hen diet implies a lower feed cost.(AU)

Multivariate modeling strategies to predict nutritional requirements of essential amino acids in semiheavy second-cycle hens

An experiment with 23 diets was performed to evaluate the effect of digestible lysine (Lys), digestible methionine + cysteine (Met+Cys), and digestible threonine (Thr) on egg production of H&N Brown second-cycle laying hens (SCLH) for 20 weeks (92-111 weeks of age) in cages under environmental conditions. Body weight (BW), feed intake (FI), feed conversion ratio (FCR), egg weight (EW), number of hen-housed eggs, and livability were also evaluated during the experiment. Diets were formulated from a central composite design that combined five levels of Lys, Met+Cys, and Thr ranging from 727 to 1159, 662 to 1055, and 552 to 882 mg/kg, respectively. Egg production (EP) data were evaluated through three different modeling strategies: egg production models, multivariate polynomial models, and artificial neural networks (ANN). A cascade-forward neural network with logsigmoid transfer function was selected as the best model according to goodness-offit statistics in both identification and validation data. One of the best scenarios for EP of H&N Brown SCLH under specific outdoor conditions was established at Lys, Met+Cys, and Thr levels of 1138, 1031, and 717 mg/hen·day, respectively. The ANN model may be an appropriate tool to study and predict EP of H&N Brown SCLH based on the combination of three different levels of essential digestible amino acids. The strategies included in this work may contribute to improving poultry performance based on modeling techniques to study other production parameters in terms of different nutritional requirements and productive conditions.

Superdosing Phytases in the Diets of Light Laying Hens: Productive Performance and Bone Quality

Two experiments were carried out with the objective of evaluating the effect of superdosing of two phytases on performance, egg quality, digestive organ biometry and bone quality of light hens in the first (58 weeks) and second (87 weeks) productive cycle. In the first cycle, 270 light hens were used, in which a completely randomized design was adopted in a 2 x 2 + 1 factorial scheme (bacterial phytase or fungal phytase x 450 FTUs or 900 FTUs + control diet). In the second cycle, 270 hens were used, following the same design as the previous experiment. The performance and quality of the eggs were evaluated in both cycles, and the biometry of the digestive organs and bone characteristics were also evaluated in the first experiment. There was no effect in the comparison between the means for the performance and egg quality (in both experiments), or for the biometric variables and bone characteristics (first experiment). There was no significant interaction between the factors for any of the variables in the two experiments. In the first experiment, egg production was higher with bacterial phytase and egg weight with fungal phytase. The mineral matter showed greater value with 450 FTUs. It is recommended to use bacterial phytase produced from Escherichia coli as it improves the performance of light laying hens. The dosage of 450 FTUs improves the mineral content of light laying hens and the use of phytase in the laying hen diet implies a lower feed cost.

Effect of probiotic Lactobacillus reuteri XC1 coexpressing endoglucanase and phytase on intestinal pH and morphology, carcass characteristics, meat quality, and serum biochemical indexes of broiler chickens

This study investigated the effect of transformed Lactobacillys reuteri on intestinal pH and morphology, carcass characteristics, meat quality, and serum biochemical indexes of broiler chickens. A total of 480 broilers were assigned to six treatment groups and fed a phosphorus-adequate diet, a phosphorus-deficient diet, or a phosphorus-deficient diet containing different L. reuteri recombinants. The results showed that transformed L. reuteri decreased the pH in the duodenum and jejunum of chickens at day 21, decreased drip loss and cooking loss of muscles, and improved muscle tenderness of chickens at days 21 and 42, but did not affect carcass characteristics and only slightly decreased abdominal fat. Transformed L. reuteri also significantly increased calcium, phosphorus, and glucose levels, decreased the uric acid level of serum at day 21, and significantly increased the glucose level and decreased the triglycerides of serum on day 42. L. reuteri pLEM4159-cel/phy increased the villi height in the duodenum of chickens at days 21 and 42. The transformed L. reuteri decreased the crypt depth in the duodenum and jejunum of chickens at day 21 and also decreased the crypt depth in the ileum and increased the villi height in the duodenum at day 42. L. reuteri pLEM4158 (phy) and L. reuteri pLEM4159-cel/phy improved the villi height in the ileum at day 42. Taken together, transformed L. reuteri can improve blood calcium, phosphorus, and glucose metabolism and intestinal development in broilers, but does not affect carcass characteristics.(AU)

Blood parameters and hepatic histopathology of broilers fed rations supplemented with essential oils

This study aimed to evaluate the hematological profile, hepatic function, and histopathology of mixed-sex broilers fed rations supplemented with microencapsulated essential oils from Cymbopogon flexuosus (lemon grass) and Lippia rotundifolia (chá-de-pedestre). One hundred and fifty Cobb chicks were housed in cages from 1 to 42 days of age in a completely randomized design, with six replicates with five chickens in each of five treatments (150 total chicks): basal diet without antibiotic growth promoter (negative control), diet with enramicina and salinomycin (positive control), diet with lemon grass essential oil, diet with L. rotundifolia essential oil, and diet with a mixture of lemon grass and L. rotundifolia essential oils. Mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) were significantly lower in untreated broilers (negative control group). Gender was not associated with erythrogram values, but aspartate aminotransferase activity (AST) was higher in females. Gamma-glutamyl transferase (GGT) was higher in chicks in the group that received rations with lemon grass oil. Broilers that received L. rotundifolia oil developed more hepatic lesions, although no effect of sex was observed related to the lesion score. Biliary hyperplasia and fibroplasias were observed in all groups, with higher histopathology scores in broilers that received diets containing L. rotundifolia oil. Mixed-sex broilers fed rations supplemented with lemon grass and L. rotundifolia essential oils have normal complete blood counts and unspecific hepatic lesions and are characterized by lipidosis, hyperplasia of the bile ducts, and fibroplasia.(AU)

Use of neem (Azadirachta indica) as a substitute for antimicrobial drugs in broiler chickens’ feed / Utilização de neem (Azadirachta indica) em substituição ao antimicrobiano em rações de frangos de corte

In the present work, we carried out an experiment aiming at evaluating the use of Neem as an antimicrobial substance in the feeds of broiler chickens. We used 240 one-day-old Cobb broiler chicks distributed in an entirely casual design, with 4 treatments, 6 repetitions and 10 birds per experimental unit, during a 21-day experimental period. Treatments consisted of a basal diet with no antimicrobial inclusion, a diet with 0.05% of tylosin, and a diet with 0.05% and 0.1% of Neem. Parameters evaluated were zootechnical performance, feed digestibility, intestinal count of Salmonella sp. and Escherichia coli, and the development of lymphoid organs. Data on the performance and metabolization of nutrients were subjected to an ANOVA and averages were compared with a post-hoc Tukey test considering α=0.05. Data on E. coli counts were analyzed with a Kruskal-Wallis test. Neem did not influence performance variables. The metabolization coefficient of dry matter and feed ethereal extract was better with tylosin (P<0.05). No growth of Salmonella was observed during the experiment. The use of Neem did not reduce E. coli population and had no influence on lymphoid organs' weight. Therefore, Neem had no effect on the performance, digestibility and intestinal microbiota of birds up to 21 days old.

Realizou-se um experimento objetivando avaliar a utilização de Neem como antimicrobiano em rações de frangos de corte. Foram utilizados 240 pintos de corte, Cobb, com 1 dia de idade, distribuídos em delineamento inteiramente casualizado, 4 tratamentos, 6 repetições, 10 aves por unidade experimental, o período experimental foi de 21 dias. Os tratamentos consistiram: dieta basal sem inclusão de antimicrobiano; dieta com 0,05% de tilosina; dieta com 0,05% e 0,1% de Neem. Avaliou-se: o desempenho zootécnico, a digestibilidade da ração, contagem intestinal de Salmonella sp. e Escherichia coli, e o desenvolvimento dos órgãos linfoides. Dados de desempenho e metabolização dos nutrientes da ração foram submetidos à ANOVA, médias comparadas pelo teste Tukey, adotou-se α=0,05. Dados de contagem de E. coli foram analisados pelo teste de Kruskal-Wallis. O Neem não influenciou as variáveis de desempenho. O coeficiente de metabolizabilidade da matéria seca e extrato etéreo da ração foi melhor com utilização de tilosina (P<0,05). Não se observou crescimento de Salmonella durante o período experimental. A utilização de Neem não reduziu a população de E. coli, e não influenciou no peso dos órgãos linfoides. A utilização do Neem não afetou o desempenho, digestibilidade e microbiota intestinal das aves até 21 dias.

Use of neem (Azadirachta indica) as a substitute for antimicrobial drugs in broiler chickens feed / Utilização de neem (Azadirachta indica) em substituição ao antimicrobiano em rações de frangos de corte

In the present work, we carried out an experiment aiming at evaluating the use of Neem as an antimicrobial substance in the feeds of broiler chickens. We used 240 one-day-old Cobb broiler chicks distributed in an entirely casual design, with 4 treatments, 6 repetitions and 10 birds per experimental unit, during a 21-day experimental period. Treatments consisted of a basal diet with no antimicrobial inclusion, a diet with 0.05% of tylosin, and a diet with 0.05% and 0.1% of Neem. Parameters evaluated were zootechnical performance, feed digestibility, intestinal count of Salmonella sp. and Escherichia coli, and the development of lymphoid organs. Data on the performance and metabolization of nutrients were subjected to an ANOVA and averages were compared with a post-hoc Tukey test considering α=0.05. Data on E. coli counts were analyzed with a Kruskal-Wallis test. Neem did not influence performance variables. The metabolization coefficient of dry matter and feed ethereal extract was better with tylosin (P<0.05). No growth of Salmonella was observed during the experiment. The use of Neem did not reduce E. coli population and had no influence on lymphoid organs' weight. Therefore, Neem had no effect on the performance, digestibility and intestinal microbiota of birds up to 21 days old.(AU)

Realizou-se um experimento objetivando avaliar a utilização de Neem como antimicrobiano em rações de frangos de corte. Foram utilizados 240 pintos de corte, Cobb, com 1 dia de idade, distribuídos em delineamento inteiramente casualizado, 4 tratamentos, 6 repetições, 10 aves por unidade experimental, o período experimental foi de 21 dias. Os tratamentos consistiram: dieta basal sem inclusão de antimicrobiano; dieta com 0,05% de tilosina; dieta com 0,05% e 0,1% de Neem. Avaliou-se: o desempenho zootécnico, a digestibilidade da ração, contagem intestinal de Salmonella sp. e Escherichia coli, e o desenvolvimento dos órgãos linfoides. Dados de desempenho e metabolização dos nutrientes da ração foram submetidos à ANOVA, médias comparadas pelo teste Tukey, adotou-se α=0,05. Dados de contagem de E. coli foram analisados pelo teste de Kruskal-Wallis. O Neem não influenciou as variáveis de desempenho. O coeficiente de metabolizabilidade da matéria seca e extrato etéreo da ração foi melhor com utilização de tilosina (P<0,05). Não se observou crescimento de Salmonella durante o período experimental. A utilização de Neem não reduziu a população de E. coli, e não influenciou no peso dos órgãos linfoides. A utilização do Neem não afetou o desempenho, digestibilidade e microbiota intestinal das aves até 21 dias.(AU)

EXPRESSÃO E POSITIVIDADE DOS TRANSPORTADORES DE CÁLCIO CALBINDIN-D28K E TRPV6 E MORFOMETRIA DO SISTEMA DIGESTÓRIO E REPRODUTOR DE CODORNAS DE POSTURA SUBMETIDAS A ESTRESSE TÉRMICO E SUPLEMENTAÇÃO COM METIONINA

Objetivou-se através deste estudo verificar se a suplementação por metionina em situações de estresse térmico por altas temperaturas pode minimizar os efeitos deletérios na produção de ovos em codornas japonesas. Para tanto, foram utilizadas 504 codornas japonesas em fase de produção (segundo ciclo), distribuídas em um delineamento inteiramente casualizado em esquema fatorial 3x4, sendo três níveis de metionina (100%, 110% e 120%) e quatro faixas de temperatura (20, 24, 28 e 32 °C). Foi avaliado pela primeira vez, através da positividade por imuno-histoquímica, e através da expressão gênica, por PCR real time, se os transportadores de cálcio, calbindin-D28k e TRPV6 que atuam na absorção, reabsorção e deposição no útero do cálcio, respectivamente em duodeno e jejuno, rim e útero seriam alterados diante tais condições (estresse térmico e suplementação com metionina). Foi visto que a suplementação com metionina em geral não aumenta a positividade ou expressão gênica de ambos os genes nos tecidos supracitados, não revertendo assim, os efeitos deletérios nos casos de estresse térmico. Exceção às glândulas uterínicas, as quais apresentaram na imunoistoquímica, uma maior positividade em animais suplementados nas temperaturas de 20 e 32ºC, evidenciando o efeito positivo da suplementação para produção de tais aves, principalmente em temperatura já considerada de estresse térmico por calor, como a de 32ºC anteriormente citada. Foi realizado, também pela primeira vez em codornas de postura sob estresse térmico e suplementadas com metionina, estudos morfométricos do sistema digestório (altura e largura de vilosidade, profundidade de cripta, relação vilo:cripta, área vilosidade, quantidade de células caliciformes, estoque de glicogênio hepático e de esteatose) e reprodutor (altura de dobras primárias uterínicas e quantidade de secundárias), os quais não apresentaram resultados significativos mediante a suplementação com metionina, uma vez que os resultados com significância foram obtidos em temperaturas termoneutras para as aves. Conclui-se que é justificácel o uso da suplementação com metionina, com o objetivo de reversão dos efeitos deletérios sobre a produção de codornas de postura submetidas a estresse térmico, uma vez que houve alterações de calbindin e TRPV6 no magno e rim, locais de produção de casca de ovo e reabsorção de cálcio respectivamente, revertendo parte dos efeitos deletérios ocasionados pelo calor e assim propondo melhorias na qualidade e produção dessas aves.

The objective of this study was to verify if methionine supplementation in high temperature heat stress situations can minimize the deleterious effects on egg production in Japanese quails. For this purpose, 504 Japanese quails in production phase (second cycle) were used, distributed in a completely randomized design in a 3x4 factorial scheme, with three levels of methionine (100%, 110% and 120%) and four temperature ranges (20, 24, 28 and 32°C). It was first evaluated by immunohistochemical positivity and gene expression by real time PCR whether the calcium transporters, calbindinD28k and TRPV6 acting on calcium uterus absorption, resorption and deposition, respectively. in duodenum and jejunum, kidney and uterus would be changed under such conditions (heat stress and methionine supplementation). It has been seen that methionine supplementation generally does not increase the positivity or gene expression of both genes in the aforementioned tissues, thus not reversing the deleterious effects in cases of heat stress. Exception to the uterine glands, which presented in immunohistochemistry, a higher positivity in animals supplemented at temperatures of 20 and 32ºC, evidencing the positive effect of supplementation for production of such birds, especially at temperature already considered heat thermal stress, such as that of 32ºC previously mentioned. Morphometric studies of the digestive system (height and width of the villus, crypt depth, villus: crypt ratio, villus area, number of goblet cells, stock) were also performed for the first time in heat stress quail and methionine supplemented. hepatic glycogen and steatosis) and breeding (height of uterine primary folds and number of secondary folds), which did not present significant results upon methionine supplementation, since the significant results were obtained at thermoneutral temperatures for the birds. It is concluded that the use of methionine supplementation is justifiable, with the objective of reversing the deleterious effects on the production of laying quails subjected to thermal stress, as there were alterations of calbindin and TRPV6 in the magnesium and kidney, production sites. eggshell and calcium resorption respectively, reversing part of the deleterious effects caused by heat and thus proposing improvements in the quality and production of these birds.

TORTA DE GIRASSOL ASSOCIADA A ENZIMAS NA ALIMENTAÇÃO DE FRANGAS DE REPOSIÇÃO DE DIFERENTES LINHAGENS

Objetivou-se avaliar a inclusão de torta de girassol (TG) e a sua metabolização com ou sem adição de enzimas nas rações de frangas de reposição leves e semipesadas nos períodos de crescimento e seus efeitos sobre desempenho, viabilidade econômica, maturidade sexual e qualidade dos ovos no início da fase de postura. No experimento I, com frangas leves, foram realizados avaliação de desempenho e dois ensaios de metabolismo. Para o desempenho, 540 frangas foram utilizadas (7 a 17 semanas de idade) em delineamento inteiramente casualizado em esquema fatorial 2 x 2 + 1 (dois níveis de inclusão de TG, 10% e 20%). Foram utilizadas, duas formas do complexo enzimático, (presença e ausência), mais um tratamento controle, com 6 repetições de 18 aves. Entre a 9ª e a 10ª semana de idade das aves, foi realizado o primeiro ensaio de metabolismo e o segundo entre a 14ª e 15ª semana, utilizando os mesmos tratamentos com 6 repetições de 5 aves. Para o desempenho no período de crescimento, não foi observada interação significativa (P>0,05) entre os níveis de TG e enzimas. Isoladamente as rações e as enzimas influenciaram significativamente (P<0,05) o consumo de ração e a conversão alimentar. Foi observada redução dos coeficientes de metabolização da matéria seca (CMMS), do nitrogênio (CMN), da energia bruta (CMEB), da energia metabolizável aparente (EMA) e energia metabolizável aparente corrigida para o balanço de nitrogênio (EMAn) das rações à medida que foi aumentando o nível de TG, mesmo com a presença de enzimas e interação significativa (P<0,05) entre os níveis de TG e enzimas para o CMMS. No final do período de crescimento, 360 aves foram transferidas para o galpão de postura permanecendo até a 35ª semana de idade mantendo o mesmo delineamento experimental. As rações não afetaram o desempenho produtivo, maturidade sexual e qualidade dos ovos, ocorrendo diminuição apenas dos valores de densidade específica em relação ao tratamento controle e interação significativa (P<0,05) para a mesma variável. No experimento II as mesmas avaliações foram realizadas com 480 frangas semipesadas no período de crescimento, com o mesmo esquema fatorial das aves leves (2 x 2 +1), porém as inclusões de TG foram de 12% e 24% com 6 repetições de 16 aves para o desempenho. Os dois ensaios de metabolismo foram realizados no mesmo período do experimento I. As repetições foram de 4 aves e ao final da 35ª semana de idade, 330 aves foram transferidas para o galpão de postura. Na fase de crescimento, não foi observada interação significativa (P>0,05) entre os níveis de TG e enzimas, em que as rações e enzimas influenciaram isoladamente (P<0,05) o consumo de ração e a conversão alimentar. Contudo, as rações não afetaram o desempenho produtivo, maturidade sexual e qualidade dos ovos, ocorrendo redução apenas dos valores de densidade específica em relação ao tratamento controle. Nos metabolismos, observou-se redução dos Coeficientes de Metabolização (CM) à medida que foi aumentando o nível de TG, mesmo com a presença de enzimas. Até 20% de inclusão de TG pode ser utilizada em rações de frangas leves e até 24% para as semipesadas sem que ocorra prejuízo do desempenho. A quantidade enzimática adicionada foi suficiente para manter o desempenho. Entretanto, não garantiu maior metabolização dos nutrientes contidos nas rações. Quanto à análise de viabilidade econômica com as aves leves, as rações que continham 20% de TG com enzimas apresentaram menores custos/Kg de ganho de peso corporal e melhores índices de eficiência e de custo. Com as semipesadas os melhores resultados para essas variáveis foram obtidos com a inclusão de 24% de TG sem enzimas.

The objective of this study was to evaluate the inclusion of sunflower cake (SC) and its metabolization with or without the addition of enzymes in the rations of light and medium weight replacement pullets during growth periods and their effects on performance, economic viability, sexual maturity and quality of eggs at the beginning of the laying phase. In the experiment I, with light pullets, performance evaluation and two metabolism tests were performed. For the performance, 540 pullets were used (7 to 17 weeks of age) in a completely randomized design in a 2 x 2 + 1 factorial scheme (two inclusion levels of SC, 10% and 20%), two forms of the enzyme complex, absence), plus a control treatment, with 6 replicates of 18 birds. Between the 9th and 10th week of the birds, the first metabolism test was performed and the second between the 14th and 15th week, using the same treatments with 6 replicates of 5 birds. As for the performance in the growth period, no significant interaction (P> 0.05) was observed between SC and enzyme levels. Rations and enzymes alone significantly influenced (P <0.05) feed intake and conversion to feed. It was observed a reduction of the coefficients of metabolization of dry matter (CMDM), nitrogen (CMN), crude energy (CMCE), apparent metabolizable energy (AME) and corrected apparent metabolizable energy for the nitrogen balance (AMEn) as SC levels were increased, even with the presence of enzymes and significant interaction (P <0.05) between the levels of SC and enzymes for CMDM. At the end of the growth period, 360 birds were transferred to the laying shed and remained there until the 35th week of age, maintaining the same experimental design. The rations did not affect the productive performance, sexual maturity and egg quality, only the values of specific density decreased in relation to the control and significant interaction (P <0.05) for the same variable. In the experiment II the same evaluations were performed with 480 medium weight pullets in the growth period, with the same factorial scheme of the light birds (2 x 2 +1), but the inclusions of SC were 12% and 24% with 6 replicates of 16 birds for performance. The two metabolism essays were performed in the same period of experiment I. The replicates were of 4 birds and at the end of the 35th week of age, 330 birds were transferred to the laying shed. In the growth phase, no significant interaction (P> 0.05) was observed between the levels of SC and enzymes, in which rations and enzymes influenced dietary intake and feed conversion alone (P <0.05). However, the rations did not affect the productive performance, sexual maturity and quality of the eggs, occurring only reduction of the values of specific density in relation to the control treatment. In the metabolisms, a reduction of Coefficients of Metabolization (CM) was observed as the level of SC was increased, even with the presence of enzymes. Up to 20% inclusion of SC can be used in light-weight rations and up to 24% for light-weight rations without performance impairment. The added enzymatic amount was sufficient to maintain performance. However, it did not guarantee greater metabolization of the nutrients contained in the rations. Regarding the economic viability analysis with the light birds, the rations that contained 20% SC with enzymes presented lower costs / Kg of body weight gain and better indices of efficiency and cost. With the medium weight pullets, the best results for these variables were obtained with the inclusion of 24% SC without enzymes.