Analysis of performance, bone characteristics, and expression of genes involved in the balance of ionic concentrations in broilers subjected to dietary electrolyte balance levels.

1. Sodium bicarbonate (NaHCO3), potassium carbonate (K2CO3), and ammonium chloride (NH4Cl) are commonly used to correct dietary electrolyte balance (DEB) in birds. However, there are many gaps in the knowledge of their effects when used simultaneously. This study investigated the effect of DEB levels on performance, femur bone characteristics and the expression of genes related to the balance of ionic concentrations in broilers at 21 days of age.2. Male Cobb broiler chickens (n = 245), aged 1-21 d, were divided into groups based on a completely randomised design with five DEB levels (110 mEq/kg, 175 mEq/kg, 240 mEq/kg, 305 mEq/kg, and 370 mEq/kg).3. The performance characteristics measured included body weight (BW), body weight gain (BWG), feed intake (FI), feed conversion (FCR) and body weight birds slaughtered (BWS).4. The bone variables assessed in the femur were weight (WE), relative bone weight (RBWE), length (L), width (WI), maximum load supported (MLS), bone-breaking resistance (BR), and Seedor index (SI). In addition, the expression of CHP1, SLC9A1, and SLC24A3 in the livers, intestines and kidneys of birds was evaluated.5. The DEB level of 370 mEq/kg, at Na+ content of 0.48%, resulted in the highest averages for L, MLS, and BR of the femur. This DEB level increased the expression of SLC9A1 in the liver and SLC24A3 in the intestine. A 240 mEq/kg DEB level decreased the expression of CHP1 in the liver, while supplementation with 110 mEq/kg increased the expression of SLC24A3 in the kidney.6. In conclusion, 370 mEq/kg DEB improved FCR and increased the mean bone characteristics of the femur (L, MLS, and BR) and the expression of SLC9A1 and SLC24A3 in the liver and intestine, respectively. These findings should be considered in future assessments of the effects of DEB levels on broilers.

Protease em dietas com baixa proteína contendo farinha de Penas para codornas de corte / [Protease in low-protein diets for meat-type quails containing feather meal]

Objetivou-se avaliar a suplementação de protease em dietas com baixa proteína contendo farinha de penas (FP) sobre o desempenho e o rendimento de carcaça de codornas de corte. Foram utilizadas 240 codornas, machos, distribuídas em delineamento inteiramente ao acaso, em esquema fatorial 2x 3 (com e sem protease x 3 níveis de FP (0%, 5% e 10%)), totalizando seis tratamentos (dieta reduzida (DR) em 8% da exigência de proteína bruta e aminoácidos + 0% FP; DR + 5% FP; DR + 10% FP; DR + 0% FP + protease; DR + 5% FP + protease e DR + 10% FP + protease), quatro repetições de 10 codornas por parcela, nas fases de oito-21 dias e oito-35 dias de idade. Observou-se interação (P≤0,05) entre os níveis de FP e protease no ganho de peso de oito-21 dias. Os níveis de FP influenciaram (P≤0,05) o consumo de ração e o ganho de peso de oito-21 e oito-35 e a conversão alimentar de oito-21 dias. Verificou-se interação (P≤0,05) entre aprotease e a inclusão de FPpara o peso corporalaos 35 dias. Conclui-se que aFP pode ser utilizada em até 5% em dietas para codornas de corte semsuplementação comprotease.(AU)

The objective of this study was to evaluate protease supplementation in low-protein diets containing feather meal (FP) on the performance and carcass yield of meat-type quails. Twenty male quails were used in a completely randomized design, in a 2 x 3 factorial scheme (with and without protease x 3 FP levels (0, 5 and 10%)), totaling six treatments (Reduced diet (RD) in 8 % of the requirement of crude protein and amino acids + 0% FP; RD + 5% FP; RD + 10% FP; RD + 0% FP + protease; RD + 5% FP + protease and RD + 10% FP + protease), four replicates of 10 quails per plot, in the phases of 8-21 days and 8-35 days of age. Interaction (P≤0.05) was observed between FP and protease levels on weight gain over the period of 8-21 days. The levels of FP influenced (P≤0.05) the feed intake and the weight gain of 8-21 and 8-35 and the feed conversion ratio of 8-21 days. There was interaction (P≤0.05) between protease supplementation and FP inclusion for body weight at 35 days. It is concluded that FP can be used up to 5% in diets for meat-type quails without protease supplementation.(AU)

Complexos enzimáticos sobre a energia metabolizável e digestibilidade dos nutrientes do milheto para frangos de corte / Enzyme complexes on metabolizable energy and nutrient digestibility of millet for broiler chickens

Objetivou-se avaliar o efeito de complexos enzimáticos sobre a energia metabolizável e o coeficiente de digestibilidade de nutrientes do milheto para frangos de corte. Quinhentos e setenta e seis frangos machos foram distribuídos em 36 gaiolas, com três tratamentos: T1 - composição de milheto sem complexo enzimático; T2 - composição de milheto com complexo enzimático (CES) e T3 - composição de milheto com complexo enzimático (CEV). Os tratamentos foram definidos com base em seis dietas (três dietas referências e três dietas testes). As dietas testes foram obtidas pela substituição de 40% da dieta referência por milheto inteiro, e a adição de enzimas consistiu de dois complexos enzimáticos: CES, constituído pelas enzimas fitase, protease, xilanase, ß-glucanase, celulase, amilase e pectinase; e CEV. constituído pelas enzimas protease, celulase e amilase. Na fase de 11 a 20 dias, a suplementação com o CEV reduziu os valores de EMA, EMAn e CDPB. A suplementação com CES melhorou o CDPB, e não houve efeito significativo para CDMS e CDEB. Na fase de 21 a 30 dias, houve menor aproveitamento da energia e dos nutrientes com as suplementações CES e CEV. Na fase de 31 a 40 dias, as suplementações reduziram os valores de EMA, EMAn, e o complexo CEV foi efetivo em aumentar o valor de CDPB. A inclusão dos complexos enzimáticos CES (fitase, protease, xilanase, ß-glucanase, celulase, amilase e pectinase) e CEV (protease, celulase e amilase) não favoreceu a utilização da energia do milheto, no entanto melhorou o coeficiente de digestibilidade da proteína do milheto nos períodos de 11 a 20 e de 31 a 40 dias de idade.(AU)

The objective of this study was to evaluate the effect of enzymatic complexes on metabolizable energy and nutrient digestibility coefficient of millet for broilers chickens. 576 male chickens, were distributed in 36 cages with three treatments: T1 - millet composition without enzymatic complex; T2 - millet composition with enzymatic complex (ECS); and T3 - millet composition with enzymatic complex (ECV). The treatments were defined from six diets (3 reference diets and 3 test diets). The test diets were obtained from the substitution of 40% for reference diet by whole millet, and the enzyme addition consisted of two enzymatic complex, ECS constituted by phytase, protease, xylanase, ß-glucanase, cellulase, amylase and pectinase enzymes, and ECV constituted by protease, cellulase and amylase enzymes. In the 11 to 20 days phase, a supplementation with the ECV reduced the AME, AMEn and CDPB values, a ECS supplementation improved the CDPB, and there was no significant effect for CDMS and CDEB. In the 21 to 30 days phase, there were less profit of the energy and nutrients with ECS and ECV supplements. In the 31 to 40 days phase as supplements reduced the values of AME, AMEn, and the ECV complex was effective in increasing the value of CDPB. The inclusion of ECS enzymatic complexes, (phytase, protease, xylanase, ß-glucanase, cellulase, amylase and pectinase) and ECV (protease, cellulase and amylase), did not favor millet's energy utilization, however, favored the millet's protein digestibility coefficient on 11 to 20 and 31 to 40 periods.(AU)

Effects of cottonseed oil and ferrous sulfate on the performance and expression of antioxidant enzymes in broilers.

Aiming to reduce feed costs, cottonseed oil (CSO) has been used as an alternative component in diets for broilers. However, this oil contains gossypol, an antinutritional agent that impacts the use of mineral elements, inhibits glucose uptake, and has a direct inhibitory action on intestinal enzymes. Nevertheless, toxic effects of gossypol can be prevented by the addition of iron salts, such as ferrous sulfate (FS), to the diet. This work was conducted to evaluate performance and gene expression of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) in the intestines of 21- and 42-day-old broilers fed 0, 2, 4, or 6% concentrations of CSO, with or without FS. All CSO diets led to weight gain (WG) at 21 D. At 42 D, an increase in WG and a decrease in feed conversion (FCR) in the diets containing FS were observed. In 21-day-old birds supplemented with 4% CSO and FS, an increase in GPx gene expression was observed when compared to the 6% level. Animals (42 day old) supplemented with 6% CSO and FS presented greater expression of SOD gene when compared to 2% CSO and FS. In addition, a higher GPx expression in broilers supplemented with 6% CSO and FS compared to 6% CSO without FS was achieved. In conclusion, including CSO in the diets of broiler favors WG in animals at 21 D of age, independent of the presence or absence of FS; and including 4% CSO and FS in the diet of these animals alters the expression of the GPx gene in the intestine, so it is not necessary to add FS at 21 D. On the other hand, in 42-day-old broilers, the addition of FS is indicated, due to increases WG, decreased FCR and at the 6% CSO level without FS increase in the expression of the SOD and GPx genes.

Effect of cottonseed oil and ferrous sulfate in broiler diets on intestinal morphometry at 42 days of age / Efeito de óleo de semente de algodão e sulfato ferroso em dietas de aves na morfometria intestinal aos 42 dias de idade

The aim of the study was to evaluate the intestinal morphometry of broilers at 42 days of age fed diets containing different levels of cottonseed oil, with and without addition of ferrous sulfate. A total of 560 male Ross chickens were used in a completely randomized design with a 4×2 factorial arrangement and five replications with 14 birds. The cottonseed oil levels tested were 0%, 2%, 4%, and 6%. At 42 days of age, one bird per replicate was collected for morphometric. Analyzed variables were villus height, crypt length and muscle wall thickness. The statistical analysis was performed using SAS, P=0.05. In the duodenum and ileum, there was no significant effect of interaction between the treatments. In the jejunum, only the length of the crypt, the treatment with cottonseed oil 2%, more ferrous sulfate resulted in lower values; however, the same oil content without ferrous sulfate led to a greater length, which was also observed in the treatment with 4% oil plus ferrous sulfate. Inclusion of cottonseed oil in broiler diets at 42 days of age does not impair their intestinal morphology. Supplementation with ferrous sulfate at these levels is unnecessary, since no improvement was observed in the intestinal morphometric.(AU)

O objetivo de estudo foi avaliar a morfometria intestinal de aves aos 42 dias de vida alimentadas com dietas contendo níveis variados de óleo de semente de algodão com e sem adição de sulfato ferroso. Um total de 560 machos de aves Ross foram usadas em estudo randomizado com amostras 4x2 e 5 replicações com 14 aves. Os níveis de óleo de semente de algodão testados foram 0%, 2%, 4%, e 6%. Aos 42 dias de idade, um pássaro por replica foi coletado para morfometria. As variáveis analisadas foram altura de villus, comprimento de cripta, e espessura de parede muscular. A análise estatística foi realizada com SAS, P=0,05. Não houve efeito significativo de interação entre tratamentos no duodeno ou íleo. No jejuno, apenas o comprimento da cripta, no tratamento com óleo de semente de algodão a 2% com mais sulfato ferroso, apresentou valor mais baixo. No entanto, o mesmo valor de óleo sem sulfato ferroso resultou em maior comprimento, resultado percebido também com 4% de óleo. Inclusão de óleo de semente de algodão em dietas de aves aos 42 dias de idade não causa danos à morfologia intestinal. Suplementação com sulfato ferroso não é necessário, já que não houve melhora em morfometria intestinal.

The response to dietary threonine in laying-type pullets during growth.

1. This study aimed to provide information on the response of laying-type pullets to dietary threonine (THR) during three periods of growth prior to the onset of lay. Different batches of Dekalb White pullets were used in three separate trial periods (from 4 to 6, 8 to 11 and 13 to 16 weeks of age) using 8 dietary THR concentrations in each period, using a completely randomised design, and with each treatment being replicated 6 times, using 15 birds per replication in period 1 and 8 birds in periods 2 and 3. In period 1 the THR content (THRc) ranged from 2.3 to 7.6 mg/g, in period 2 from 1.7 to 5.5 mg/g, and in period 3 from 1.4 to 4.7 mg THR/g feed. 2. Body weight gain, food intake and the deposition of protein and lipid in the feather-free body and in the feathers were measured in each period. Linear regressions were fitted to all data falling below the break point defined by the broken stick regression, to estimate the efficiency of utilisation of THR. The maximum protein growth rate was 4.0 ± 0.2, 5.3 ± 0.4 and 3.5 ± 0.5 g/d in periods 1, 2 and 3, respectively. 3. The efficiency of utilisation of dietary THR for THR deposition in each period was the same, at 0.85 ± 0.1 mg/mg. As dietary THRc decreased, the amount of body lipid deposition increased. 4. With this information, it is possible to determine the daily requirement for THR for the potential growth of body and feather protein in growing pullets.

Níveis nutricionais de cálcio para aves de corte ISA label criadas sob semiconfinamento / Dietary calcium levels for ISA label broilers raised in semi-confined system

Determinaram-se os níveis nutricionais de cálcio (Ca) para aves, machos e fêmeas, da linhagem ISA Label, nas fases inicial (um a 28 dias), crescimento (28 a 56 dias) e final (56 a 84 dias). Foram realizados três ensaios, um para cada fase, e, em cada ensaio, 480 aves com idade correspondente à fase de criação foram alojadas em 24 unidades experimentais com áreas de abrigo e de pastejo. Foi utilizado delineamento inteiramente ao acaso, em esquema fatorial 4x2 (Ca e sexo), totalizando oito tratamentos com três repetiç ões de 20 aves. Avaliaram-se: ganho de peso (GP); consumo de dieta (CD); conversão alimentar (CA); teores de fósforo (PT), de cálcio (CaT) e de cinzas na tíbia (CT) e resistência à quebra óssea (RQO). Na fase inicial, recomenda-se 1,16 por cento de Ca na dieta, para aves de ambos os sexos, na fase de crescimento, 0,78 e 0,88 por cento de Ca para machos e fêmeas, respectivamente, e, na fase final, 0,69 por cento de Ca na dieta para ambos os sexos.

The nutritional calcium (Ca) levels were determined for ISA Label broilers in the starter (1 to 28 days), growing (28 to 56 days), and finishing (56 to 84 days) phases. Three trials were conducted, one for each phase and in each trial, 480 birds with age corresponding to the phase were housed in 24 experimental units with shelter and pasture areas. The experimental design was completely randomized in a factorial arrangement of 4x2 (Ca levels and sex), totaling eight treatments with three replicates of 20 birds. Body weight gain (BWG); feed intake (FI); feed per gain (FG); contents of phosphorus (TP), calcium (TCa) and ash (TA) in tibia; and bone breaking strength (BSB) were evaluated. At the starter phase, 1.16 percent of Ca is recommended in the diet for birds of both sexes. At the growing phase, 0.78 and 0.88 percent of Ca for males and females, respectively, are recommended and at the finishing phase, the level of 0.69 percent of Ca is recommended in diet for both sexes.

Exigências de lisina digestível para aves de corte da linhagem ISA Label criadas em semiconfinamento / Digestible lysine requirements for ISA Label broilers reared in free-range system

Foram realizados três experimentos para determinar as exigências de lisina digestível para aves da linhagem ISA Label, de ambos os sexos, criadas em semiconfinamento durante as fases: inicial (1 a 28 dias), de crescimento (28 a 56 dias) e final (56 a 84 dias). Em cada experimento, foram utilizadas 480 aves, alojadas em 24 piquetes, cada um contendo abrigo coberto de 3,13m² e área de pastejo de 72,87m². O delineamento experimental utilizado foi o inteiramente ao acaso, em esquema fatorial 4x2 (níveis de lisina e sexo) com três repetições de 20 aves cada. Os níveis de lisina digestível avaliados foram: 0,850; 0,970; 1,090 e 1,210 por cento na fase inicial; 0,750; 0,870; 0,990 e 1,110 por cento na fase de crescimento e 0,640; 0,760; 0,880 e 1,000 por cento na fase final. Foram mensuradas as variáveis de desempenho, característica de carcaça, deposição de proteína e gordura corporal, peso e teor de proteína das penas. Com base nos resultados de desempenho, recomendam-se 1, 041; 1,006 e 0,760 por cento de lisina digestível em rações para aves ISA Label nas fases inicial, de crescimento e final, respectivamente.

Three assays were carried out to determine digestible lysine requirement for ISA Label, both genders, in free-range system on starter (1 to 28 days), growing (28 to 56 days) e finishing phases (56 to 84 days). A total of 480 birds were distributed into 24 pens, each one composed by shelter (3.13m²) and pasture (72.87m²). The experimental design was a completely randomized in factorial arrangement (four levels of lysine and two genders) with three replicates of 20 birds. The digestible lysine levels were 0.85, 0.97, 1.09, and 1.21 percent for starter; 0.75, 0.87, 0.99, and 1.11 percent for growing; and 0.64, 0.76, 0.88, and 1.00 percent for finishing phases. The analyzed parameters were performance, carcass yield, protein and fat deposition, weight, and protein in the feathers. Based on bird performance the estimated digestible lysine level, was 1.041, 1.006, and 0.760 percent for the starter, growing and finishing phases, respectively.