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ABSTRACT Two experiments were conducted to assess the impact of an enzyme complex (EC) on the metabolizability coefficients of dry matter (MCDM), crude protein (MCCP), and ether extract (MCEE) and on the nitrogen-corrected apparent metabolizable energy (AMEn) of corn gluten meal, soybean protein concentrate, dried bovine plasma, and poultry offal meal. Additionally, the experiments aimed to evaluate how EC affected broiler performance. In experiment I, 720 day-old Cobb 500® broilers were assigned to a completely randomized design using a 4 × 2 factorial arrangement. The main factors considered were the feedstuff (corn gluten meal, soybean protein concentrate, dried bovine plasma, and poultry offal meal) and the presence or absence of EC. The broilers were housed in 45 pens, using five replicates, with ten birds in the pre-starter phase and six birds in the starter phase. This design resulted in eight treatment groups, including one reference diet group. In experiment II, 1140 day-old Cobb 500® chicks were allotted in a completely randomized design, employing a 4 × 2 factorial arrangement, with the same main factors as in experiment I. Birds were housed in 48 pens, using six replicates/30 birds, yielding eight treatments. The use of the EC did not lead to improvements in digestibility of the feedstuffs. However, the addition of EC resulted in enhanced body weight gain and improved feed conversion ratios across all phases of broiler growth. Enzyme complex inclusion did not affect feed intake. While the EC did not enhance the metabolizability of nutrients in feedstuffs individually, broilers fed diets containing these feedstuffs and supplemented with EC exhibited improved performance at 42 days of age. This suggests that the impact of the EC varies depending on whether it is observed at the feedstuff or diet level.

ABSTRACT This study aimed to evaluate the effect of including an emulsifier (soybean lecithin) and two lipid sources (soybean oil and chicken fat) on the performance and intestinal morphology of broiler chickens. A total of 576 one-day-old Cobb® 500 male chicks were housed in a completely randomized design, with treatments divided in a 2 × 2 factorial arrangement (with and without emulsifier and two lipid sources – soybean oil or chicken fat), totaling four treatments with eight replications and 18 chicks per plot. The experimental diets were formulated to be isoenergetic and isoproteic. The use of chicken fat improved the live weight at the starter rearing stage. However, the use of the emulsifier improved the live weight at the grower and finisher phases. No interaction effect was observed between treatments for performance. The intestinal morphology showed an increase in duodenal villus height with the use of chicken fat and emulsifier. The ileum had an increase in villus height in chickens fed the diet with soybean oil and emulsifier. Supplementation of the emulsifier resulted in positive results in the live weight of chickens at 35 and 42 days of age, in addition to increasing the villus height in the small intestine.

ABSTRACT The objective of this study was to evaluate the effects of prebiotics, alone and in combination with antibiotics, on broiler performance, carcass yield, intestinal permeability, and intestinal morphometry. A total of 1440 day-old male Cobb 500 chicks were distributed in a completely randomized design, with four treatments and 10 replications per treatment. The treatments used were a basal diet without prebiotics and antibiotics (BD), a basal diet with antibiotics (AB), a basal diet with prebiotics (PRE), and a basal diet with antibiotics and prebiotics (AB+PRE). To perform the treatment, the antibiotic zinc bacitracin and a prebiotic of S. cerevisiae-derived mannan-oligosaccharides and beta-glucans were used. The treatments did not affect the performance of birds from 1 to 7 and 1 to 21 days of age. From 1 to 35 and 1 to 42 days, birds fed the AB+PRE treatment had higher feed intake than those fed the AB treatment. From 1 to 35 days, birds fed the AB+PRE treatment showed a worse feed conversion ratio. However, there was no difference in carcass yield between treatments. A higher number of goblet cells was observed in the duodenum and ileum of birds fed AB+PRE, but lower counts were obtained in birds fed AB. Intestinal histomorphometry displayed similar responses between both ages regarding antibiotic and prebiotic treatments, except in the ileum at 42 days, in which the antibiotic elicited a better response. Intestinal permeability analysis showed no significant difference between diets. The use of prebiotics, alone or in combination with antibiotics, does not improve the performance of broilers.

Objective Two experiments were conducted to evaluate the effect of enzyme complex (EC) on the standardized ileal digestibility (SID) of amino acids (AA) in corn gluten meal (60%) (CGM), soy protein concentrate (SPC), dried bovine plasma (DBP), and poultry offal meal (POM). Experiments I and II were conducted with broilers in the pre-starter (1 to 7 days of age) and starter (1 to 21 days of age) phases, respectively. Methods The treatments consisted of a protein-free diet (PFD) containing feedstuffs either supplemented with EC (xylanase, amylase, and protease) or not. In Experiment I, a total of 360 one-day-old male Cobb-500 broiler chicks were randomly housed in 45 pens, resulting in five replicates with eight birds each, totalizing eight treatments and one PFD group. In Experiment II a total of 270 one-day-old male Cobb-500 broiler chicks were randomly housed in 45 pens, resulting in five replicates with six birds each, totalizing eight treatments and one PFD group. The PFD groups were used to assess the endogenous AA losses. The birds were slaughtered to collect the ileal content. Results In the pre-starter phase, the SID of arginine, branched chain-aminoacids, glycine, serine, aspartate, and glutamic acid increased with EC addition. The EC improved the SID of arginine and glutamic acid of CGM; the SID of valine and cystine of SPC; the SID of leucine, glycine, and aspartate of POM and the SID of isoleucine of DBP. In the starter phase, the SID of isoleucine, phenylalanine and glycine increased in EC-supplemented diets. The EC improved the SID of isoleucine of DBP; the SID of phenylalanine of CGM and POM. The SID of AA of SPC was not influenced by the EC. Conclusion The addition of an EC to broiler pre-starter and starter diets is efficient in increasing the SID of AA on SPC, POM, and DBP.

Objective An experiment was conducted to evaluate the effect of different levels of crude protein (CP) and two rearing systems (cage and floor), on blood parameters and digestive and reproductive organ development of brown laying hens. Methods 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 CP (140, 150, 160, and 180 g/kg), in a total of eight treatments and five replicates of 10 birds each with initial body weight of 1,877 g (laying hen in cage) and 1,866 g (laying hens in floor). The parameters evaluated were plasma total protein, albumin, uric acid, total cholesterol, relative weights of oviduct, abdominal fat, liver, gizzard, crest and dewlap, length of small intestine and oviduct. Results The blood parameters were similar in birds reared in cage and floor systems. The birds reared on the floor showed greater small intestine and oviduct weight (%) and lower liver and pancreas weight (%). A significant interaction was observed between factors for the relative gizzard, crest and dewlap weight, serum protein, uric acid, and total cholesterol (p

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 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.

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

The main purpose of this study was to evaluate the characteristics of eggs produced by Japanese quails fed with guava extract. A total of 400 eggs collected from the quails fed with experimental diets, were distributed in a completely randomized design in factorial arrangement 4 x 4 with main effects including four dietary levels of guava extract (0, 3, 6 and 9 g kg-1) and four storage periods (0, 9, 18 and 27 days) totalizing 16 treatments with five replicates of five eggs. The eggs were produced by Japanese quails, fed with experimental diets. The diets were isonutritive formulated by corn-soybean basis. The eggs were stored for different periods, at the same conditions, to constitute the treatments. The parameters evaluated were egg weight loss (g and %), yolk color, Haugh unit, specific gravity, eggshell thickness and pH of the yolk and albumen. Data were submitted to ANOVA, and means were compared using Scott-Knott test, using α = 0.05. The specific gravity of fresh eggs was better with the use of 6 g kg-1 of guava extract in the diet. The use of 3 g kg-1 of guava extract resulted in smaller eggshell thickness of fresh eggs. The Haugh unit was affected just by the storage periods. The dietary guava extract (3, 6 or 9 g kg-1) increased the pH of albumen in eggs stored for 27 days. The use of 6 g kg-1 of guava extract in quails diet increase the specific gravity in fresh eggs and increase the yolk color when the eggs are stored.

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.

Ninety barrow piglets weaned at 21 days old were used to evaluate the effects of guanidinoacetic acid (GAA) supplementation on their performance and blood creatinine and creatine kinase (CK) levels during the nursery phase (21 to 63 days old). The piglets were distributed in a randomized block design with five treatments (0, 0.05, 0.10, 0.15, and 0.20% GAA inclusion), six repetitions, and three animals per repetition. The experimental rations were formulated to meet the nutritional requirements for the phases of 21 to 32, 33 to 42 and 43 to 63 days of age. The experimental diets and water were offered ad libitum throughout the experimental period. At 42 and 63 days old, blood was collected from one animal in each experimental unit for creatinine and creatine kinase analysis. The analysed variables were daily weight gain (DFG), daily feed intake (DFI), and feed conversion (FC) in the 21 to 42 days old and 21 to 63 days old of the nursery phase. All variables were subjected to analysis of variance and regression analysis. We adopted ? = 0.05, and considered a trend to be present when ? was between 0.05 and 0.10. In the pre-initial period (21 to 42 days old), there was an increasing trend in daily weight (P = 0.069), which increased to the level of 0.97% of GAA inclusion. The DFI and FC were not significantly affected by the addition of different GAA levels in the diet. Creatinine levels in the blood at 42 and 63 days old were not significantly influenced by the treatments. The level of CK at 42 days old showed an increasing trend (P = 0.077) that occurred quadratically to the level of 0.085% of GAA inclusion, with no significant difference for this variable at 63 days old. The use of GAA did not promote improvements in performance or blood creatinine and CK levels in piglets in the nursery phase.

ABSTRACT Seventy-two barrows were used to evaluate the effects of the use of soy protein concentrate (SPC) in diets of post-weaning piglets on their performance, intestinal histomorphometry, and blood parameters. Piglets were weaned at 21 days of age and distributed in a randomized-block experimental design with four treatments (0, 3, 6, and 9% SPC), six replications, and three piglets per replication. Diets were formulated to meet the requirement of the piglets according to phases of 21 to 32, 33 to 42, and 43 to 66 days of age. Both feed and water were provided ad libitum during the entire experiment. The feed of the phase of 43 to 66 days was based on corn and soybean meal. In the period between 21 and 32 days of age, the use of SPC in the diet did not impact the daily weight gain (DWG) or the daily feed intake (DFI) of the piglets, whereas there was a linear effect on feed conversion (FC), which decreased as the levels of SPC in the feed were increased. In the period between 33 and 42 days of age, a linear effect was observed on FC, which increased as the level of SPC in the feed was increased. In this period, no effects of SPC were observed on DWG or DFI. Inclusion of SPC in the diets does not influence performance, intestinal histomorphometry, or blood parameters of piglets in the period between 21 and 66 days of age.

Abstract The objective of this study was to determine the nutritional requirement for calcium and the best calcium:phosphorus ratio in the diet for laying hens from 24 to 40 weeks of age. 324 Hy-Line W-36 birds were distributed in a completely randomized design in 3x3 factorial scheme, consisting of three levels of calcium (3.9, 4.2, and 4.5%) and three calcium:phosphorus ratios (9.3, 10.53, and 12.12:1) totaling nine treatments, six replicates and six birds each. We evaluated performance, egg quality, bone characteristics, balance of calcium and phosphorus, and mortality. There was no interaction (P> 0.05) between calcium levels and calcium:phosphorus ratio for the variables, but levels of calcium affected (P

ABSTRACT This work aimed to investigate the antioxidant capacity of the guava agroindustrial waste as a functional additive in broiler feed to improve the performance and meat quality of boilers. The experiment was conducted in a completely randomized design, consisting of four treatments and six replicates with 12 birds. Treatments included different levels of guava byproduct in the feed: 0, 0.5, 1.0, and 1.5%. We evaluated the performance of broilers at 7 and 21 days old. At 21 days old, two birds from each experimental unit were euthanized for intestine histologic evaluation (duodenum, jejunum, and ileum) and breast and deboned thigh samples were collected for analyzes of pH, colorimetry (L*, a*, and b*), and thiobarbituric reactive substances (TBARS). The use of guava byproduct in the diet at 7 days old did not affect feed intake and feed conversion of the birds. However, the body weight and weight gain increased linearly with the inclusion of the byproduct. At 21 days old, the guava byproduct did not depress the performance of birds. There was no effect of treatments on villus height, crypt depth, and villus:crypt ratio of the duodenum and jejunum of the birds. The inclusion of guava byproduct resulted in lower crypt depth and linear increase in villus:crypt ratio of the ileum. There was no significant difference in pH and colorimetry of the breast and thigh. With increasing inclusion of byproduct, TBARS value was reduced to 0.72%, indicating greater lipid stability in thigh meat in this inclusion amount. Guava byproduct can be used as an alternative antioxidant additive in broiler feed because it does not depress the productive performance and improves thigh meat quality of boilers.

An experiment was carried out to evaluate the requirement of methionine +cystine for growing pullets at starter phase (1 to 6 weeks old) and its effect on the laying phase. In the first experiment, 720 birds (50% Lohmann LSL and 50% Lohmann Brown) at one week of age were distributed on a completely randomized design, 5 x 2 factorial arrangement (levels of met + cys and strain), with four replications and 18 birds each. The levels of total methionine + cystine studied were 0.536; 0.616; 0.696; 0.776; and 0.856 %. At 22 weeks of age, 240 birds were used for the second experimental phase. The diets given to birds at this phase was the same for all the treatments. In the production phase, the residual effects of the experimental diets provided during the initial phase on the production parameters were evaluated. The level of methionine + cystine recommended for white-egg and brown-egg pullets in the period from 1 to 6 weeks of age are 0.778 % of total methionine + cystine (0.700% met + cis digestible) and 0.739% of total methionine + cystine (0.665% of digestible methionine + cystine), respectively. Keywords: amino acids; egg; hens; requeriments; sexual maturity.

Two-hundred sixteen white laying hens were used to assess the ideal ratio of digestible threonine:lysine in diets for laying hens at 24 to 40 weeks of age. Birds were assigned to a randomized block design, with six treatments, six replicates per treatment and six birds per experimental unit. The cage was used as the blocking criterion. Experimental diets contained different digestible threonine:digestible lysine ratios (65, 70, 75, 80, 85 and 90%) with 142 g/kg of crude protein. Experimental diets were formulated to be isonitrogenous and isocaloric with different contents of L-glutamic acid. Feed intake (g/hen/d), egg production (%), egg weight (g), egg mass (g/hen/d), feed conversion ratio (kg/dozen and kg/kg egg), eggshell weight (g), albumen weight (g), yolk weight (g) and body weight gain (g) were assessed. The maximum egg production was observed at 78% digestible threonine:digestible lysine ratio, while the best values of feed conversion ratio (kg/dozen egg) and feed conversion ratio (kg/kg of egg) were observed at 77.6% and 75%, respectively. Feed intake, egg mass and egg contents (yolk, albumen and eggshell) were not affected by treatments. The estimated digestible threonine:digestible lysine ratio of Hy-Line W36 laying hens at 24 to 40 weeks of age is 78%, corresponding to 5.70 g/kg of dietary digestible threonine.

Two hundred fifty-two Hy-Line W36 laying hens were allotted in a randomized block design with 6 treatments, 7 replicates and 6 hens per experimental unit in order to determine the ideal digestible isoleucine: digestible lysine (Ile:Lys) ratio for laying hens aged 24-40 weeks. Experimental diets contained 5.92, 6.33, 6.73, 7.14, 7.54 and 7.95 g/kg of digestible isoleucine, resulting in different Ile:Lys ratios (0.73:1, 0.78:1, 0.83:1, 0.88:1, 0.93:1 and 0.98:1). Experimental diets were isonitrogenous, with different dietary contents of glutamic acid, and made isocaloric by adjusting the levels of cornstarch. All essential amino acids were provided proportionally to digestible lysine. Feed intake, egg production, egg weight, egg mass, feed conversion ratio per egg mass, feed conversion ratio per dozen eggs, albumen, yolk and eggshell content were assessed. Feed intake, egg production, egg mass and feed conversion ratio were influenced by Ile: Lys ratios quadratically. The egg weight was not affected by Ile: Lys ratio. No differences were observed in the egg quality according to Ile: Lys ratios. The data indicates that the optimum digestible isoleucine: digestible lysine ratio for laying hens aged 24-40 week is 0.84:1, corresponding to the consumption of 681 mg of isoleucine and 811 mg of lysine/hen day-1.

Resumo Objetivou-se determinar a exigência nutricional de cálcio e a melhor relação cálcio:fósforo em rações para poedeiras leves de 24 a 40 semanas de idade. Foram utilizadas 324 aves Hy-Line W-36, distribuídas em delineamento inteiramente casualizado, esquema fatorial 3x3, sendo três níveis de cálcio (3,9; 4,2 e 4,5 %) e três relações cálcio/fósforo (9,3; 10,53 e 12,12/1), totalizando nove tratamentos, seis repetições e seis aves por unidade experimental. Avaliou-se o desempenho produtivo, a qualidade do ovo, as características ósseas, o balanço de cálcio e fósforo e a mortalidade. Não houve interação (P>0,05) entre os níveis de cálcio e as relações cálcio/fósforo para nenhuma das variáveis, porém os níveis de cálcio promoveram efeito (P

Four experiments were conducted to study the requirements of available phosphorus (aP) for commercial male broilers of 1-10 day of age (exp.1), 11-21 days of age (exp. 2), 22-33 day of age (exp. 3) and 34-46 days of age (exp. 4), at a constant calcium:aP ratio. A complete randomized design was used in each experiment. The experimental diets were fed ad libitum to 8 replicate groups of ten broilers in each. The increments in the levels of aP ranged from 2.0 to 5.5 g/kg (exp. 1), 1.9 to 5.4 g/kg (exp. 2), 1.8 to 5.3 g/kg (exp. 3) and 1.7 to 5.2 g/kg (exp. 4), in 0.7 g/kg. The parameters evaluated were body weight gain, feed intake, feed conversion ratio and bone parameters. The level of aP in the diet influenced the performance of broilers of 1-10 and 11-21 days of age, but did not affect the performance of broilers at 22-33 and 34-46 days of age. Feed intake was not affected. The requirements of aP and Ca for male broilers from 1-10, 11-21, 22-33 and 34-46 days of age are 4.82 and 9.64 g/kg, 4.10 and 8.20 g/kg, 3.95 and 7.90 g/kg and 3.19 g.kg and 6.38 g/kg, respectively. The results indicate that low levels aP were required because the requirements of the mineral reduced as birds aged. Provided there is no excess of dietary levels of Ca, using a Ca:aP ratio of 2:1 may reduce the dietary levels of aP.

Four trials were conducted to determine the requirements of available phosphorus (aP) of female broiler chicks from 1 to 10 (exp.1), 11 to 21 (exp.2), 22 to 33 (exp.3), and from 34 to 46 (exp.4) days of age, keeping the calcium:available phosphorus ratio equal to 2:1. In each trial, 480 Cobb broilers were randomly allotted in a completely randomized design with 6 treatments, 8 replicates and 10 birds per pen. The levels of aP ranged from 2.0 to 5.5 g/kg (Exp. 1), 1.9 to 5.4g/kg (exp. 2), 1.8 to 5.3 g/kg (exp. 3) and 1.7 to 5.2 g/kg of diet (exp. 4), in increments of 0.7 g/kg. The experimental diets were formulated using corn and soybean meal and the available phosphorus was considered 33% of total phosphorus. The characteristics evaluated were body weight gain, feed intake, feed conversion ratio and bone parameters. For female broiler chicks from 1 to 10; 11 to 21; 22 to 33; and from 34 to 46 days of age, the levels of available phosphorus and calcium recommended are 4.59 and 9.18; 3.88 and 7.76; 3.58 and 7.16; and 2.56 and 5.12 g/kg of diet, respectively.

The objective of this study was to determine the ideal digestible tryptophan:digestible lysine ratio in diets for laying hens from 24 to 40 weeks of age. Two hundred and forty Hy-Line W-36 laying hens at 24 weeks of age were distributed in a completely randomized design, with five treatments, eight replicates and six birds per experimental unit. The digestible tryptophan levels in the experimental diets were 1.57; 1.68; 1.79; 1.90 and 2.01 g/kg, providing ratios of digestible tryptophan:digestible lysine of 0.215; 0.230; 0.245; 0.260 and 0.275. The increase in the levels of digestible tryptophan in the diet linearly improved the feed intake, digestible tryptophan intake, digestible lysine intake, egg production, egg mass, feed conversion per egg mass and utilization efficiency of digestible lysine for eggs mass. There were quadratic effects from the digestible tryptophan levels on egg weight. For the efficiency of utilization of digestible lysine for egg mass, there was better adjustment of the data to the LRP model. The level of digestible tryptophan in the diet from which the plateau occurred was 0.184%. This level corresponded to the intake of 142 mg/bird/day of digestible tryptophan and digestible tryptophan:digestible lysine ratio of 0.252. The ideal digestible tryptophan:digestible lysine ratio recommended in diets for laying hens from 24 to 40 weeks of age is 0.252 (25.2%).

Two hundred and fifty-two Hy-Line W36 laying hens were allotted in a completely randomized design with 6 treatments, 7 replicates and 6 hens per experimental unit in order to determine the ideal ratio of isoleucine (Ile) in relation to lysine (Lys) to laying hens aged 42-58 weeks. Experimental diets contained digestible Ile at different levels, resulting in different Ile:Lys ratios (0.73:1; 0.78:1; 0.83:1; 0.88:1; 0.93:1 and 0.98:1). A basal diet was formulated to provide Isoleucine in levels below recommendations. This diet was supplemented with L-isoleucine to make up the 6 diets. Each diet was made isonitrogenous by varying the dietary contents of glutamic acid and isocaloric by adjusting the contents of cornstarch. All essential amino acids were provided proportionally to lysine. Egg production, egg weight, egg mass, feed conversion ratio, albumen, yolk and eggshell contents were recorded and compiled at every 28-day period. No differences were observed in the performance over a wide range of dietary isoleucine concentrations from 5.76 to 7.73 g/kg corresponding to 0.73:1 to 0.98:1 Ile:Lys ratios. The lowest Ile:Lys ratio (0.73:1) was sufficient to ensure satisfactory performance of birds, corresponding to the consumption of 534 mg of isoleucine and 731 mg of lysine/day.

Foi conduzido um experimento com o objetivo de estabelecer a exigência nutricional de metionina+cistina para poedeiras leves no segundo ciclo de produção. Foram utilizadas 180 poedeiras leves no período de 79 a 95 semanas de idade, submetidas a uma ração basal deficiente em metionina+cistina e suplementada com 0,00; 0,053; 0,108; 0,161; ou 0,214% de DL-metionina (98%), de forma a proporcionar 0,490; 0,542; 0,594; 0,648; e 0,698% de metionina+cistina digestíveis nas rações. Os níveis de suplementação obedeceram às relações de metionina+cistina:lisina de 75, 83, 91, 99 e 107 com a lisina fixada em 0,653%. O delineamento experimental foi inteiramente casualizado, com cinco níveis de metionina+cistina, seis repetições e seis aves por unidade experimental. Os níveis de metionina+cistina na ração tiveram efeito linear sobre a conversão alimentar por dúzia e por massa de ovos, a taxa de postura, a massa de ovos e o índice de albúmen e efeito quadrático sobre o peso dos ovos e a unidade Haugh. A porcentagem dos componentes dos ovos não foram influenciada pelos níveis de metionina+cistina na ração. A exigência de metionina+cistina para poedeiras leves é superior a 0,698%, valor que corresponde a consumo de pelo menos de 796 mg/ave/dia.It was conducted an experiment with the objective of setting the nutritional requirement of methionine+cystine for white-egg laying hens in the second production cycle. It was used 180 white-egg laying hens from 79 to 95 weeks of age submitted to a basal diet deficient in methionine+cystine, supplemented with 0.00; 0.053; 0.108; 0.161 or 0.214% of DL-methionine (98%) to provide 0.490; 0.542; 0.594; 0.648 and 0.698% of digestible methionine+cystine in the rations. Levels of supplementation followed ratios of methionine+cystine:lysine of 75, 83, 91, 99 and 107 with lysine fixed at 0.653%. A complete randomized design with five levels of methionine + cystine was used, with six replicates and six birds per experimental unit. Levels of methionine+cystine in the ration linearly affected feed conversion per dozen of eggs and mass of eggs, laying rate, egg mass and albumen index and they quadratically affected weight of eggs and Haugh unity. Percentage of components of the eggs was not affected by levels of methionine+cystine in the ration. Requirement of methionine+cystine for white-egg laying hens is higher than 0.698%, which corresponds to a consumption of at least 796 mg/bird/day.

Um experimento foi conduzido com o objetivo de estimar o nível ótimo de treonina digestível para poedeiras leves e semipesadas no segundo ciclo de postura. Foram utilizadas 360 aves, sendo 180 poedeiras leves e 180 poedeiras semipesadas, distribuídas em delineamento inteiramente casualizado, num arranjo fatorial 5 x 2 (5 níveis de treonina x 2 linhagens de poedeiras). Os níveis de treonina digestível utilizados foram de 0,380; 0,413; 0,445; 0,478 e 0,511%. Foram avaliados os dados de desempenho (produção, peso e massa de ovo), componentes dos ovos (albúmen, gema e casca), a qualidade interna dos ovos (unidades Haugh, índice de albúmen e de gema), percentual de ovos não comerciais e parâmetros de peso corporal. Pelos resultados obtidos, estimou-se para poedeiras leves nível de 0,446% de treonina digestível, correspondendo a um consumo diário de 487 mg/ave e relação treonina/lisina igual a 68, enquanto que para poedeiras semipesadas o nível estimado foi de 0,465% de treonina digestível, com consumo diário de 505 mg/ave e relação treonina/lisina igual a 71. Comparando a relação mg de treonina digestível por grama de ovo produzido, foram estimados valores de 9,5 e 10,0 mg de treonina/grama de ovo produzida.An experiment was carried out to estimate the optimum level of digestible threonine for white-egg and brown-egg laying hens in the second laying cycle. It was used 360 laying hens, 180 were white-egg and 180 were brown-egg laying hens which were distributed in a complete randomized design in 5 x 2 factorial arrangement (5 levels threonine x 2 lines of laying hens). The levels of digestible threonine used were the following: 0.380, 0.413, 0.445, 0.478 and 0.511%. It was evaluated performance data (production, egg weight and mass), egg components (albumen, yolk and shell), egg internal quality (Haugh units, albumen and yolk indexes) and percentage of non-commercial eggs and body weight parameters. Through the obtained results, it was estimated for white-egg laying hens, levels of digestible threonine of 0.446%, which matches a daily intake of 487 mg/hens and a lysine: threonine relationship equal to 68; for brown-egg laying hens, the estimate level of digestible threonine was 0.465% with a daily intake of 505 mg/hens and a lysine: threonine relationship of 71. By comparing the relationship mg digestible threonine per gram of produced eggs, values of 9.5 and 10.0 mg threonine/gram egg are estimate; gram of produced egg.

Com o objetivo de determinar os níveis de aminoácidos sulfurosos digestíveis para estabelecer a relação ideal metionina + cistina/lisina em rações para poedeiras leves no período de 42 a 58 semanas de idade, 216 aves da marca comercial Hy-Line W36 foram distribuídas em delineamento de blocos casualizados com seis dietas, seis repetições e seis aves por unidade experimental. O nível de lisina utilizado na dieta experimental foi de 0,770% para consumo médio esperado de 731 mg/ave/dia de lisina e de 95 g/ave/dia de ração. Os níveis de aminoácidos sulfurosos digestíveis foram obtidos a partir de uma dieta basal deficiente em metionina + cistina digestível (0,65%), suplementada com 0,00; 0,05; 0,10; 0,15; 0,20 e 0,25% de DL-metionina (99,2%), de forma a proporcionar relações metionina + cistina/lisina de 84, 91, 97, 104, 110 e 117%. O período experimental teve duração de 16 semanas e foi subdividido em quatro ciclos de coleta dos ovos, cada um de 28 dias. Houve efeito quadrático dos níveis de 0,826% e 0,775% de metionina + cistina digestível sobre a produção de ovos e a eficiência de utilização de lisina por produção total de ovos, respectivamente. O nível de metionina + cistina digestível considerado exigência para poedeiras leves no período de 42 a 58 semanas de idade foi de 0,775%, que corresponde a consumo de 708 mg/ave/dia de metionina + cistina digestível e relação metionina + cistina/lisina de 101%.Aiming at determining levels of digestible sulfurous amino acids to establish the ideal methionine + cystine/lysine relationship in rations for light-weight laying hens in the period from 42 to 58 weeks of age, 216 birds of the commercial brand Hy- Line W36 were distributed in a randomized block design with 6 diets, 6 repetitions and 6 birds per experimental unit. The level of digestible lysine used in the experimental diet was 0.770% for an expected average consumption of 731 mg/hen/day of lysine and 95 g/hen/day of ration. Levels of digestible sulfurous amino acids were obtained from a basal diet deficient in digestible methionine + cystine (0.65%), supplemented with 0.00; 0.05, 0.10, 0.15, 0.20 and 0.25% of DL-methionine (99.2%), so to provide a methionine + cystine/lysine relationship of 84, 91, 97, 104, 110 and 117%. The experimental period lasted for 16 weeks and it was subdivided in 4 cycles of egg collection, each one corresponding to 28 days. There was a quadratic effect of the digestible methionine + cistine levels of 0.826% and 0.775% on the egg production and lysine utilization efficiency for total egg production, respectively. The digestible methionine + cystine level considered as a requirement for light-weight laying hens in the period from 42 to 58 weeks of age were 0.775%, corresponding to digestible methionine + cystine consumption of 708 mg/hen/day, and a methionine + cystine/lysine relationship of 101%.

O experimento foi conduzido para determinar os coeficientes de digestibilidade verdadeira dos aminoácidos utilizando-se o método de alimentação forçada com galos adultos cecectomizados. Os alimentos estudados foram: quirera de arroz; farelo de arroz integral; milho; sorgo; farelo de trigo; farelo de soja; farelo de algodão 28% e farelo de algodão 38%; levedura 43%; levedura 40%. Os valores médios dos coeficientes de digestibilidade verdadeira dos aminoácidos essenciais e não-essenciais foram, respectivamente: 77,53 e 67,21% para a quirera de arroz; 73,33 e 52,54% para o farelo de arroz integral; 73,33 e 52,54% para o milho; 84,48 e 67,21% para o sorgo; 70,75 e 48,55% para o farelo de trigo; 89,37 e 85,22% para o farelo de soja; 74,85 e 74,13 para o farelo de algodão 28%; 77,50 e 72,46% para o farelo de algodão 38%; 49,16 e 48,63% para a levedura 43%; e 46,03 e 38,88% para a levedura 40%. Os valores obtidos dos coeficientes de digestibilidade verdadeira de aminoácidos essenciais e não-essenciais dos alimentos estudados permitem elaborar rações mais eficientes para aves.This experiment was carried out to determine the values of the real digestibility coefficients of amino acids by using the method of "forced feed" with cecectomized roosters. The studied food were the following: rice bran, whole rice meal, corn, sorghum, wheat bran, soybean meal, cotton meal 28%, cotton meal 38%, yeast sugar cane 43% and yeast sugar cane 40%. The mean values of real digestibility coefficients of essential and non-essential amino acids were, in percentage, the following: for rice bran, 77.53 and 67.21; for rice meal, 73.33 and 52.54; for corn, 84.65 and 74.42; for sorghum, 84.48 and 67.29; for wheat bran, 70.75 and 48.55; for soybean meal, 89.37 and 85.22; for cotton meal 28%, 74.85 and 74.13; for cotton meal 38%, 77.50 and 72.46; for yeast sugar cane 43%, 49.16 and 48.63; and yeast sugar cane 40%, 46.03 and 38.88. The values of the coefficients of real digestibility of essential and nonessential amino acids of feedstuffs studied allow to formulate more efficient rations for birds.

Foram realizados quatro ensaios para determinar a energia metabolizável aparente (EMA) e a energia metabolizável aparente corrigida pelo balanço de nitrogênio (EMAn) de dez alimentos de origem vegetal para aves em diversas idades. Os alimentos estudados foram: farelo de soja 45%, farelo de soja 48%, soja integral extrusada, soja integral desativada, soja integral micronizada, farinha de soja desativada, concentrado proteico de soja, farelo de glúten de milho 21%, gérmen de milho e quirera de arroz. Utilizou-se o método de coleta total de excretas, em delineamento experimental inteiramente casualizado, com 11 tratamentos e 6 repetições nos quatro ensaios. No primeiro, segundo e terceiro ensaios, foram utilizados frangos de corte com 10 a 17; 26 a 33; e 40 a 47 dias de idade, respectivamente, e no quarto ensaio galos com 25 semanas de idade. Os valores de EMAn (kcal/kg), na matéria natural, determinados no primeiro, segundo, terceiro e quarto ensaios foram, respectivamente: 2.069, 2.148, 2.272 e 2.231 para o farelo de soja 45%; 2.214, 2.225, 2319 e 2.247 para o farelo de soja 48%; 3.322, 3.331, 3.405 e 3.493 para a soja integral extrusada; 3.016, 3.067, 3.139 e 3.388 para a soja integral desativada; 3.557, 3.638, 3.828 e 3.869 para a soja integral micronizada; 2.292, 2.348, 2.518 e 2.502 para a farinha de soja desativada; 2.356, 2.399, 2.509 e 2.486 para o concentrado proteico de soja; 1.826, 1.882, 2.110 e 1.942 para o farelo de glúten de milho 21%; 2.605, 2.764, 2.925 e 2.832 para o gérmen de milho; e 2.967, 3.029, 3.096 e 3.026 para a quirera de arroz.Four assays were carried out to determine the apparent metabolizable energy (AME) and nitrogen corrected apparent metabolizable energy (AMEn) of ten feedstuffs of vegetable origin for poultry at different ages. The chemical composition of the ten feedstuffs was also determined: 45% soybean meal, 48% soybean meal, extruded full-fat soybean, deactivated full-fat soybean, micronized full-fat soybean, deactivated soybean meal, soybean protein concentrate, corn gluten meal 21%, corn germ and broken rice. The method of total excreta collection was used and a randomized complete experimental design was used with 11 treatments and six replications, in the four assays. In the 1st, 2nd and 3rd assays broiler chicks were used aged 10 to 17, 26 to 33 and 40 to 47 days, respectively, and in the 4th assay roosters were used with 25 weeks of age. The AMEn values (as-fed basis) determined in the 1st, 2nd, 3rd and 4th assay were, respectively: 2069, 2148, 2272 and 2231 for 45% soybean meal; 2214, 2225, 2319 and 2247 for 48% soybean meal; 3322, 3331, 3405 and 3493 for extruded full-fat soybean; 3016, 3067, 3139 and 3388 for deactivated full-fat soybean; 3557, 3638, 3828 and 3869 for micronized full-fat soybean; 2292, 2348, 2518 and 2502 for deactivated soybean meal; 2356, 2399, 2509 and 2486 for soybean protein concentrate; 1826, 1882, 2110 and 1942 for corn gluten meal 21%; 2605, 2764, 2925 and 2832 for corn germ; and 2967, 3029, 3096 and 3026 for broken rice.

Um experimento foi conduzido com o objetivo de determinar a exigência de lisina digestível para poedeiras leves no período de 24 a 40 semanas de idade. Foram utilizadas 216 poedeiras Hy-Line W36 em delineamento em blocos casualizados com seis tratamentos, seis blocos e seis aves por unidade experimental. Os tratamentos consistiram de uma ração basal, com 14,54% de proteína bruta, deficiente em lisina digestível (0,545%), e suplementada com seis níveis de L-lisina HCl (78%): 0,00; 0,059; 0,118; 0,177; 0,237 e 0,295%. Considerando a digestibilidade da lisina de 97,6%, a quantidade de L-lisina.HCl adicionada em cada ração forneceu 0,00; 0,045; 0,090; 0,135; 0,180 e 0,225% de lisina digestível respectivamente, resultando em rações com 0,545; 0,590; 0,635; 0,680; 0,725 e 0,770% de lisina digestível. Os consumos de ração e de lisina, a produção de ovos, o peso médio dos ovos, a massa de ovos, a conversão alimentar/dúzia de ovos, o índice de albúmen e o peso final das aves apresentaram resposta linear ao aumento dos níveis lisina digestível. Os níveis de lisina digestível tiveram efeito quadrático sobre a conversão alimentar/massa de ovos, mas não tiveram efeito significativo sobre a unidade Haugh, o índice de gema e os componentes dos ovos. A exigência de lisina digestível foi estimada em, no mínimo, 0,770% na ração, que corresponde a consumo de 759 mg de lisina digestível/ave/dia.The objective of this study wast to determine the requirement of digestible lysine for light-weight laying hens 24 to 40 weeks of age. Two hundred and sixteen Hy-Line W36 light-weight laying hens were allotted to a randomized complete blocks with six treatments, six blocks and six hens per experimental unit. The treatments consisted of a basal diet, with 14.54% crude protein, deficient in digestible lysine (0.545%), supplemented with six levels of L-lysine HCl (78%) 0.00; 0.059; 0.118; 0.177; 0.237 and 0.295%. Considering the digestibility of the lysine to be 97.6%, the amount of L-lysine. HCl added in each diet supplied 0.00; 0.045; 0.090; 0.135; 0.180 and 0.225 digestible lysine, respectively, resulting in diets with 0.545; 0.590; 0.635; 0.680; 0.725 and 0.770% digestible lysine. Feed intake, lysine intake, egg production, average egg weight, egg mass, feed conversion (kg feed/egg dozen), albumen index and final weight gain of the chickens showed a linear response with increase in the digestible lysine levels. There was a quadratic effect for the levels of digestible lysine on feed conversion/egg mass but no significant effect on Haugh Units, yolk index and egg components was detected. The digestible lysine requirement was estimated to be at least 0.770% of the diet, corresponding to the intake of 759 mg of lysine digestible/hen/day.

Objetivou-se determinar a exigência de metionina+cistina digestíveis no período de 54 a 70 semanas de idade. Utilizaram-se 360 aves (180 Lohmann LSL e 180 Lohmann Brown) em esquema fatorial 5 × 2 (5 níveis de metionina+cistina digestíveis e 2 variedades) no delineamento inteiramente casualizado com 6 repetições e 6 aves por unidade experimental. Os tratamentos consistiram de dietas suplementadas com cinco níveis de DL-metionina (98%), de forma a proporcionar 0,492; 0,544; 0,596; 0,648 e 0,700% de metionina+cistina digestíveis. Os parâmetros avaliados foram: produção de ovos, peso dos ovos, massa de ovos, consumo de ração, consumo de metionina+cistina digestível, conversão alimentar, componentes dos ovos (albúmen, gema e casca), qualidade interna do ovo (unidades Haugh, índice de albúmen e de gema), percentual de ovos não-comerciais e variação de peso corporal. Os níveis de metionina+cistina digestíveis estudados influenciaram a produção de ovos, o peso dos ovos, a massa de ovos, o consumo de ração, o consumo de metionina+cistina digestíveis, a conversão alimentar, o peso da gema e da casca e a variação de peso corporal. As exigências de metionina+cistina digestíveis foram estimadas pelos modelos de regressão polinomial. O valor estimado para a exigência de poedeiras leves foi de 0,645% de metionina+cistina digestíveis, correspondente a um consumo de 712 mg/ave.dia de metionina+cistina e 12,5 g de metionina+cistina digestível/g de massa de ovo produzida. Para as poedeiras semipesadas, a exigência foi de 0,655% de metionina+cistina digestíveis na dieta, correspondente a um consumo de 723 mg/ave.dia de metionina+cistina e 13,2 g de metionina+cistina digestível/g de massa de ovo produzida.This research was carried out using 360 laying hens (180 Lohmann LSL and 180 Lohmann Brown), to establish the nutritional requirement of digestible methionine+cystine in the period from 54 to 70 weeks of age. A completely randomized experimental design, in a 5 × 2 factorial arrangement (5 levels of digestible methionine+cystine and 2 laying hen strain), with 6 replications and 6 hens per experimental unit, was used. The treatments consisted of diets supplemented with 5 levels of DL-methionine (98%), resulting in 0.492, 0.544, 0.596, 0.648 and 0.700% of digestible methionine+cystine in diets. The parameters analyzed were: egg production, egg weight, egg mass, feed intake, digestible methionine+cystine intake, feed conversion, egg components (albumen, yolk and shell), internal quality (Haugh unit, albumen index and yolk index), the percentage of eggs does not trade and the body weight gain. The levels of methionine+cystine digestibles studied influenced the egg production, egg weight, egg mass, feed intake, digestible methionine+cystine intake, feed conversion, weight yolk and shell, and the body weight gain. The requirements of digestible methionine+cistine were estimated by polynomial regression models. The digestible methionine+cystine requirement, estimated for the laying hens light-weight was of 0.645% in the ration, corresponding to daily intake per hen of 712 mg and 12.5 g of methionine+cystine digestibles/g egg mass produced. For the laying hens semi-heavy was of 0.655% in the ration, corresponding to daily intake per hen of 723 mg and 13.2 g of methionine+cystine digestibles/g egg mass produced.

Foram realizados quatro ensaios de metabolismo com a finalidade de determinar a energia metabolizável aparente (EMA) e a energia metabolizável aparente corrigida (EMAn) de dez alimentos em aves em diversas idades. Os alimentos testados foram: milho, farelo de soja, sorgo, farelo de trigo, farelo de arroz integral, duas farinhas de penas, duas farinhas de vísceras e plasma sangüíneo. Utilizou-se o método de coleta total de excretas, em delineamento experimental inteiramente casualizado, com 11 tratamentos (dez alimentos e uma ração-referência) e seis repetições. No primeiro ensaio, foram utilizados 528 pintos de corte machos de 10 a 17 dias de idade, totalizando oito aves por repetição; no segundo ensaio, 396 frangos de corte machos de 26 a 33 dias de idade, com seis aves por repetição; no terceiro ensaio, 264 frangos de corte machos de 40 a 47 dias de idade, com quatro aves por repetição; e, no quarto ensaio, 132 galos, com duas aves por repetição. A idade das aves influenciou os valores de EMA e EMAn do farelo de soja, do sorgo, do farelo de arroz integral, das farinhas de penas e do plasma sangüíneo, enquanto, para o farelo de trigo, teve efeito apenas sobre a EMAn.Four assays were carried out to determine the apparent metabolizable energy (AME) and the corrected apparent nitrogen metabolizable energy (AMEn) of ten feeds for poultry at different poultry ages. The feeds studied were: corn grain, soybean meal, ground sorghum, wheat bran, integral rice bran, two kinds of feather meal, two kinds of poultry viscera meal and spray-dried plasma. The method of total excreta collection was used to determine the AME and AMEn values. The broiler chicks were distributed on a completely randomized experimental design, with 11 treatments, six replications, with different number of animals by replication according to the assay. In the first assay, 528 male broiler chicks in the period from 10 to 17 days of age were used, with eight animals per replication. In the second assay, 396 male broiler chicks in the period from 26 to 33 days of age were used, with six animals per replication. In the third assay, 264 male broiler chicks in the period from 40 to 47 days of age were used, with four animals per replication. In the fourth assay, 132 roosters were used, with two animals per replicate. There was an effect of age on the AME and AMEn values of the following feeds: soybean meal, ground sorghum, integral rice bran, two kinds of feather meal and spray-dried plasma, where the oldest broilers provided the highest AME and AMEn values. Wheat bran was affected by age only for the AMEn values.

Um experimento foi realizado com o objetivo de determinar a exigência de lisina digestível no período de 54 a 70 semanas de idade. Utilizaram-se 360 aves com 54 semanas de idade, 180 (Lohmann LSL e 180 Lohmann Brown) em um delineamento inteiramente casualizado em esquema fatorial 5 × 2, composto de cinco níveis de lisina digestível e duas linhagens (leves e semipesadas), com seis repetições e seis aves por unidade experimental. Utilizou-se uma dieta basal deficiente em lisina digestível suplementada com cinco níveis de L-lisina HCl (78%), de forma a resultar em dietas com 0,555; 0,605; 0,655; 0,705 e 0,755% de lisina digestível. Avaliaram-se a produção de ovos, o peso e a massa de ovos, o consumo de ração, a conversão alimentar, os pesos de albúmen, gema e casca, unidades Haugh, os índices de albúmen e de gema, o percentual de ovos não-comerciais e a variação de peso corporal. Nas poedeiras leves, houve efeito linear dos níveis de lisina sobre os consumo de ração e de lisina, o índice de gema e os pesos de albúmen e de gema e efeito quadrático sobre a produção de ovos, o peso e a massa de ovos, a conversão alimentar e o peso da casca. Nas poedeiras semipesadas, houve efeito linear dos níveis de lisina sobre o consumo de lisina e o peso dos ovos e efeito quadrático sobre a produção de ovos, a massa de ovos, a conversão alimentar e o peso da casca. As exigências de lisina digestível para as poedeiras leves e semipesadas no período de 54 a 70 semanas de idade são de 0,724 e 0,692% da dieta, que correspondem a 784 e 748 mg de lisina digestível/ave/dia e 14,9 e 14,5 g de lisina digestível/g de massa de ovo produzida.An experiment was performed to determine the dietary digestible lysine requirement of hens (Lohman LSL and Lohman Brown) from 54 to 70 weeks of age. Three hundred and sixty hens were randomly assigned to 5 × 2 factorial arrangement (Lys levels by hen strain), according to the dietary treatments withj six replicates (groups) of 6 birds. An experimental diet was formulated to contain deficient digestible lysine levels in order to be supplemented with lysine (L-Lys-HCL,78%) originating the five dietary treatments (0.555; 0.605; 0.655; 0.705 and 0.755% of digestible lysine). The parameters analyzed were egg production, egg weight, egg mass, feed intake, lysine intake, feed conversion, albumen weight, yolk weight and shell weight, Haugh unit, albumen index and yolk index, percentage of non-commercial eggs and body weight gain. There was linear effect of lysine levels to light laying hens on feed intake, lysine intake, yolk index, albumen weight, yolk weight and quadratic effect on egg production, egg weight, egg mass, feed conversion and shell weight. For brown-type laying hens, there was linear effect of lysine levels on lysine intake and egg weight and quadratic effect on egg production, egg mass, feed conversion and shell weight. The digestible lysine requirements were estimated through polynomial regression models. Estimates of digestible lysine requirements were calculated as 0.724 and 0.692% for light laying hens and brown-type laying hens, respectively, which corresponds to 784 and 748 mg/hen/day and 14.9 and 14.5 g of digestible lysine/g egg mass produced, in the period from 54 to 70 weeks of age.

Este trabalho foi realizado para determinar o valor nutricional do milheto e avaliar sua utilização como alimento energético em rações para frangos de corte de 1 a 21 dias de idade. Foram realizados dois experimentos: no primeiro, foram determinados os teores de matéria seca (88,53%), energia bruta (3.604 kcal/kg), energia metabolizável aparente corrigida (2.656 kcal/kg), proteína bruta (12,71%), fibra bruta (5,40%), extrato etéreo (3,10%), cálcio (0,029%) e fósforo (0,31%) e, no segundo experimento, foi determinado o desempenho produtivo dos frangos no período de 1 a 21 dias de idade alimentados com rações contendo 0; 10; 20; 30 ou 40% de milheto. Utilizou-se delineamento experimental inteiramente casualizado em esquema fatorial 5 × 2, composto de cinco níveis de milheto e dois sexos, com quatro repetições de 20 aves por unidade experimental. Os parâmetros analisados foram o consumo de ração, o ganho de peso e a conversão alimentar. O desempenho dos frangos alimentados com as rações com maiores níveis de milheto foi significativamente melhor, o que pode estar relacionado ao aumento do nível de óleo na dieta. A inclusão de milheto é recomendável em níveis de até 20% em rações para frangos de corte de 1 a 21 dias de idade.This research was carried out to determine the nutritional value of pearl millet, and to evaluate their utilization as energetic source in broiler diets from 1 to 21 days old. Two experiment were conducted: in the first, the chemical composition (dry matter, crude protein, ether extract, calcium and phosphorus) and gross energy, apparent metabolizable energy corrected by nitrogen balance were determined. In the second experiment, the performance of broilers from 1 to 21 days old fed diets with 0, 10, 20, 30 and 40% of pearl millet were determined. A completely randomized design, in a 5 × 2 factorial arrangement (level of millet and sex), with four replicates and 20 birds per experimental unit, was used. The determined values of chemical composition were: dry matter (88.53%), gross energy (3,604 kcal/kg), crude protein (12.71%), crude fiber (5.40%), ether extract (3.10%), calcium (0.029%) and phosphorus (0.31%) and, in the second experiment, apparent metabolizable energy corrected by nitrogen balance (2,656 kcal/kg). The analyzed traits were: feed intake, weight gain and feed/gain ratio. The performance of broilers fed rations with higher levels pearl millet was better, which could be related to the increase of oil level in diet. The inclusion of pearl millet up to 20% is recommended in the rations for broilers from 1 to 21 days old.

ABSTRACT In this study, we evaluated the effects of substitution of partial and total spray-dried blood plasma (BP) with soy protein concentrate (SPC) in the diet of post-weaning piglets on their performance, intestinal histomorphometry, and blood parameters. Fifty-four castrated male piglets, weaned at an average age of 21 days and an initial average weight of 7.01±0.294 kg, were distributed in a completely randomized block design, with three diets (0%SPC-5%BP, 2.5%SPC-2.5%BP, and 5%SPC-0%BP), six replicates, and three piglets per experimental unit. The experimental feeds were formulated to meet the requirements of the piglets at 21-32 and 33-42 days of age (pre-starter diet) and 43-66 days of age (starter diet). From 21 to 32 and 21 to 42 days of age, daily feed intake, daily weight gain, and final weight of the animals were higher in the group fed 2.5%SPC-2.5%BP and 0%SPC-5%BP. From 21 to 66 days of age, daily weight gain and daily feed intake were higher in the animals fed 2.5%SPC-2.5%BP. No effect was observed on the histomorphometry variables. The total leukocyte count was higher in animals fed 2.5%SPC-2.5%BP and 5%SPC-0%BP and the lymphocyte count was lower in the piglets that received 0%SPC-5%BP. The combined use of soy protein concentrate and spray-dried blood plasma in the feeds of piglets between 21 and 42 days of age improves their productive performance.