Amino acid and energy digestibility of conventional corn dried distillers grains with solubles, high protein distillers dried grains, and corn fermented protein, and impacts on turkey poult growth performance and intestinal characteristics

Amino acids (AA) are an expensive nutritional components of poultry diets. Distillers dried grains with solubles (DDGS) is the primary co-product produced by the dry grind bioethanol industry, although new technologies are being implemented to produce high protein distillers dried grains (HP-DDG) and corn fermented protein (CFP), but data on their nutritive value in poultry are lacking. Two experiments (EXP) were conducted to determine the energy and AA digestibility of DDGS, HP-DDG, and CFP in poults in addition to a feeding trial to evaluate increasing dietary levels of HP-DDG and CFP on growth performance and intestinal characteristics. In EXP 1, 6 different DDGS sources were evaluated using poults to determine their nitrogen-corrected apparent metabolizable energy (AMEn) concentrations, and cecectomized roosters were used to determine their standardized ileal (SID) AA digestibility (SID-AA). In EXP 2, AMEn and SID-AA for HP-DDG and CFP were determined in young poults, and a feeding trial was conducted to evaluate growth performance and intestinal morphology and permeability of poults fed diets containing 7.5 and 15% HP-DDG or CFP from 1 to 32 d of age. In EXP 1, the AMEn concentration among the DDGS samples ranged from 2,530 to 3,573 kcal/kg DM but was not different (P = 0.57) among the samples, with an average SID for LYS of 66.6%. In EXP 2, different (P = 0.001) AMEn concentrations for HP-DDG and CFP were observed (3,114 and 3,760 kcal/kg DM, respectively), with the SID for LYS being 66.55 and 77.00% for HP-DDG and CFP, respectively. Including HP-DDG or CFP into the diet at 7.5 and 15% had no effect (P > 0.05) on growth, feed intake, or feed conversion. Neither co-product nor its inclusion rate affected intestinal morphology and permeability (P > 0.05). Overall, DDGS, HP-DDG, and CFP are excellent sources of AMEn and digestible AA, with dietary inclusion rates of up to 15% of HP-DDG or CFP having no impact on growth or intestinal characteristics.

Prediction of net energy of feeds for broiler chickens

Net energy (NE) enables the prediction of more accurate feed energy values by taking into account the heat increment which is approximately 25% of apparent metabolizable energy (AME) in poultry. Nevertheless, application of NE in poultry industry has not been practiced widely. To predict the NE values of broiler diets, 23 diets were prepared by using 13 major ingredients (wheat, corn, paddy rice, broken rice, cassava pellets, full-fat soybean, soybean meal, canola meal, animal protein, rice bran, wheat bran, palm kernel meal and palm kernel oil). The diets were formulated in order to meet the birds' requirements and get a wide range of chemical compositions (on DM basis; 33.6% to 55.3% for starch; 20.8% to 28.4% for CP, 2.7% to 10.6% for ether extract [EE] and 7.0% to 17.2% for NDF), with low correlations between these nutrients and low correlations between the inclusion levels of ingredients allowing for the calculation of robust prediction equations of energy values of diets or ingredients. These diets were fed to Ross 308 broilers raised in 12 open-circuit respiratory chambers from 18 to 23 d of age (4 birds per cage) and growth performance, diet AME content and heat production were measured, and dietary NE values were calculated. The trial was conducted on a weekly basis with 12 diets measured each week (1 per chamber), 1 of the 23 diets (reference diet) being measured each week. Each diet was tested at least 8 times. In total, 235 energy balance data values were available for the final calculations. Growth performance, AME (15.3 MJ/kg DM on average) and AME/GE (79.4% on average) values were as expected. The NE/AME value averaged 76.6% and was negatively influenced by CP and NDF and positively by EE in connection with efficiencies of AME provided by CP, EE and starch for NE of 73%, 87% and 81%, respectively. The best prediction equation was: NE = (0.815 × AME) - (0.026 × CP) + (0.020 × EE) - (0.024 × NDF) with NE and AME as MJ/kg DM, and CP, EE and NDF as % of DM. The NE prediction equations from this study agree with other recently reported equations in poultry and are suitable for both ingredients and complete feeds.

Re-evaluation of recent research on metabolic utilization of energy in poultry: Recommendations for a net energy system for broilers

Different energy systems have been proposed for energy evaluation of feeds for domestic animals. The oldest and most commonly used systems take into account the fecal energy loss to obtain digestible energy (DE), and fecal, urinary and fermentation gases energy losses to calculate metabolizable energy (ME). In the case of ruminants and pigs, the net energy (NE) system, which takes into account the heat increment associated with the metabolic utilization of ME, has progressively replaced the DE and ME systems over the last 50 years. For poultry, apparent ME (AME) is used exclusively and NE is not yet used widely. The present paper considers some important methodological points for measuring NE in poultry feeds and summarizes the available knowledge on NE systems for poultry. NE prediction equations based on a common analysis of three recent studies representing a total of 50 complete and balanced diets fed to broilers are proposed; these equations including the AME content and easily available chemical indicators have been validated on another set of 30 diets. The equations are applicable to both ingredients and complete diets. They rely primarily on an accurate and reliable AME value which then represents the first limiting predictor of NE value. Our analysis indicates that NE would be a better predictor of broiler performance than AME and that the hierarchy between feeds is dependent on the energy system with a higher energy value for fat and a lower energy value for protein in an NE system. Practical considerations for implementing such an NE system from the commonly used AME or AMEn (AME adjusted for zero nitrogen balance) systems are presented. In conclusion, there is sufficient information to allow the implementation of the NE concept in order to improve the accuracy of feed formulation in poultry.

Review: Nutrient and energy supply in monogastric food producing animals with reduced environmental and climatic footprint and improved gut health

With more efficient utilisation of dietary nutrients and energy, diversified production systems, modifications of diet composition with respect to feedstuffs included and the use of free amino acids, the negative impact of animal food production on the environment and climate can be reduced. Accurate requirements for nutrients and energy for animals with differing physiological needs, and the use of robust and accurate feed evaluation systems are key for more efficient feed utilisation. Data on CP and amino acid requirements in pigs and poultry indicate that it should be possible to implement indispensable amino acid-balanced diets with low- or reduced-protein content without any reduction in animal performance. Potential feed resources, not competing with human food security, can be derived from the traditional food- and agroindustry, such as various waste streams and co-products of different origins. In addition, novel feedstuffs emerging from aquaculture, biotechnology and innovative new technologies may have potential to provide the lack of indispensable amino acids in organic animal food production. High fibre content is a nutritional limitation of using waste streams and co-products as feed for monogastric animals as it is associated with decreased nutrient digestibility and reduced dietary energy values. However, minimum levels of dietary fibre are needed to maintain the normal physiological function of the gastro-intestinal tract. Moreover, there may be positive effects of fibre in the diet such as improved gut health, increased satiety, and an overall improvement of behaviour and well-being.

Validation of a 3-point model for the determination of energy values using the regression method in broiler chickens

Two experiments (Exp.) were conducted to validate a 3-point model for the regression method of determining ME, using canola meal (CM) and wheat as test ingredients (TI). Corn-soybean meal-based test diets (TD) contained 0, 100, 200, or 300 g/kg CM, added at the proportional expense of all energy contributing ingredients for Exp. 1, and 0, 150, 300, or 450 g/kg wheat for Exp. 2. For each Exp., 192 Cobb 500 male broiler chickens were weighed and allotted by BW to 1 of 4 treatments at d 21 post hatching in a randomized complete block design. Growth performance and metabolizability responses were evaluated for linear and quadratic effects using orthogonal contrasts, and ileal digestible energy (IDE), ME, and MEn of TI were determined by regressing the TI-associated energy against the dry matter intake of TI using a generalized linear model. Four data sets were used to determine ME, using all possible 3 and 4-point combinations of TD in each Exp. Increasing TI inclusion elicited linear decreases (P < 0.01) in the digestibility and metabolizability of DM and GE in the 2 studies. The ME of CM obtained from the 4 data sets ranged from 1,731 to 1,992 kcal/kg DM, however, excluding the highest concentration of CM produced the highest estimate of ME, whereas the other 3 sets ranged from 1,731 to 1,793 kcal/kg DM. The ME of wheat from the 4 data sets had a smaller range of 3,041 to 3,106 kcal/kg DM. Excluding the highest concentration of either TI produced higher standard errors for the estimate of ME compared to the other 3 sets (42 and 36% greater SE, respectively). Results for IDE and MEn were similar. These data indicate that there is no difference in the variation of estimates between the 3 and 4-point models, provided that the inclusion of the TI is adequate and both models represent the linearity and variability of responses.

Methodologies for energy evaluation of pig and poultry feeds: A review

The cost of feed represents an important part of the total cost in swine and poultry production (>60%) with energy accounting for at least 70% of feed cost. The energy value of ingredients or compound feeds can be estimated as digestible (DE), metabolisable (ME) and net energy (NE) in pigs and ME and NE in poultry. The current paper reviews the different methods for evaluating DE, ME and NE of feeds for monogastric animals and their difficulties and limits, with a focus on NE. In pigs and poultry, energy digestibility depends on the chemical characteristics of the feed, but also on technology (pelleting, for instance) and animal factors such as their health and body weight. The ME value includes the energy losses in urine that are directly dependent on the proportion of dietary N excreted in urine resulting in the concept of ME adjusted for a zero N balance (MEn) in poultry. For poultry, the concept of true ME (TME, TMEn), which excludes the endogenous fecal and urinary energy losses from the excreta energy, was also developed. The measurement of dietary NE is more complex, and NE values of a given feed depend on the animal and environmental factors and also measurement and calculation methods. The combination of NE values of diets obtained under standardised conditions allows calculating NE prediction equations that are applicable to both ingredients and compound feeds. The abundance of energy concepts, especially for poultry, and the numerous feed and animal factors of variation related to energy digestibility or ME utilisation for NE suggest that attention must be paid to the experimental conditions for evaluating DE, ME or NE content. This also suggests the necessity of standardisations, one of them being, as implemented in pigs, an adjustment of ME values in poultry for an N retention representative of modern production conditions (MEs). In conclusion, this review illustrates that, in addition to numerous technical difficulties for evaluating energy in pigs and poultry, the absolute energy values depend on feed and animal factors, the environment, and the methods and concepts. Finally, as implemented in pigs, the use of NE values should be the objective of a more reliable energy system for poultry feeds.

Trends in feed evaluation for poultry with emphasis on in vitro techniques

Accurate knowledge of the actual nutritional value of individual feed ingredients and complete diets is critical for efficient and sustainable animal production. For this reason, feed evaluation has always been in the forefront of nutritional research. Feed evaluation for poultry involves several approaches that include chemical analysis, table values, prediction equations, near-infrared reflectance spectroscopy, in vivo data and in vitro digestion techniques. Among these, the use of animals (in vivo) is the most valuable to gain information on nutrient utilization and is more predictive of bird performance. However, in vivo methods are expensive, laborious and time-consuming. It is therefore important to establish in vitro methods that are reliable, rapid and practical to assess the nutritional quality of feed ingredients or complete diets. Accuracy of the technique is crucial, as poor prediction will have a negative impact on bird performance and, increase feed cost and environmental issues. In this review, the relevance and importance of feed evaluation in poultry nutrition will be highlighted and the various approaches to evaluate the feed value of feed ingredients or complete diets will be discussed. Trends in and practical limitations encountered in feed evaluation science, with emphasis on in vitro digestion techniques, will be discussed.

Metabolizable and net energy values of corn stored for 3 years for laying hens

The apparent metabolizable energy (AME), AME corrected to zero-nitrogen retention (AMEn), and net energy (NE) values of 2 corn samples both stored for 3 yr were determined in laying hens with reference diet substitution method. Reference diet was formulated according to standard layer requirement, and test diets contained 50% of corn samples and 50% of the reference diet. Fifty-four Hy-Line Brown hens at the age of 36 wk were used. The heat production and energy metabolism of birds were measured in open-circuit respiratory chambers with 6 replicates (3 birds per replicate) per diet in a randomized design. Birds were fed experimental diets for 7 D in the chamber as adaptation. During the following 3 D, feed intake, metabolizable energy value, nitrogen balance, energy balance, egg production, O₂ consumption, CO₂ production, and energy efficiency were determined. The AME values of corn 1 and corn 2 were 3,485 and 3,675 kcal/kg DM, respectively. The corresponding AMEn values were 3,452 and 3,596 kcal/kg DM, and the NE values were 2,575 and 2,693 kcal/kg DM, respectively. The NE:AME ratios of corn 1 and corn 2 were 74.4 and 73.3%, respectively. The NE:AMEn ratios of corn 1 and corn 2 were 75.0 and 74.9%, respectively. The AME, AMEn, and NE values of the 2 corn samples both stored for 3 yr were lower than the literature values for fresh corn.

Implementation of net energy evaluating system in laying hens: Validation by performance and egg quality

Three experiments were conducted to determine the effect of different dietary net energy (NE) and AMEn ratios (NE:AMEn) on performance, egg quality, and heat production (HP) in laying hens. In experiment 1, 62 Hy-Line Brown hens were fed 2 treatments with 31 replicates from 44 to 54 wk of age. In experiment 2, 600 hens of the same strain were fed 3 treatments from 22 to 42 wk of age with 10 replicates. Both used a completely randomized design. Diets were based on corn, wheat, wheat bran, barley, soybean meal, canola meal, meat and bone meal, and canola oil. In both experiments, the NE:AMEn ratio of diets was increased with higher oil inclusion compared with T1 controls. The AMEn (kcal/kg), NE (kcal/kg), ether extract (g/kg), and CP (g/kg), respectively, on a DM basis in experiment 1 was T1: 3,011, 2,288, 42, 202 and T2: 3,023, 2,374, 81, 203; and in experiment 2, T1: 3,026, 2,324, 25, 187; T2: 2,949, 2,315, 61, 185; and T3: 3,026, 2,397, 73, 181. Increasing the ratio of NE:AMEn decreased feed intake (P < 0.001) and increased egg mass (P < 0.05) in experiment 2 and increased egg weight (P < 0.01), decreased feed conversion ratio (P < 0.01), increased egg albumen % (P < 0.001), and decreased yolk % (P < 0.05) and shell % (P < 0.05) compared with T1 controls in both experiments. Haugh units and yolk color scores were increased with high NE:AMEn in both experiments (P < 0.001; P < 0.01). Experiment 3 was conducted in calorimetry chambers to measure HP in birds fed experiment 2 diets. Increasing the NE:AMEn increased total retained energy (RE), RE as fat, and RE in the body (kcal/kg BW^0.75/D) and NE:AME. The results indicate that using oil to increase the NE:AMEn results in improved performance and egg quality and more efficient energy utilization.

Energy values of triticale or sorghum distillers' dried grains with solubles and rye fed to broiler chickens

The current experiments were conducted to determine ileal digestible energy (IDE), metabolizable energy (ME), and nitrogen-corrected ME (MEn) of triticale distillers' dried grains with solubles (TDDGS), sorghum distillers' dried grains with solubles (SDDGS), or rye for broiler chickens using the regression method. Five diets including a corn-soybean meal reference diet and four assay diets, prepared by adding TDDGS or SDDGS at 10% or 20% of the diet to partly replace energy-yielding ingredients in the reference diet, were used. Each of the five diets was fed to eight replicate cages of six birds per replicate cage from day 14 to 21 post-hatching. Similarly in experiment 2, corn-soybean reference diet and two assay diets in which rye at 20% or 40% replaced energy-yielding sources in the reference diet and each of the three diets was fed to eight replicate cages of eight birds per replicate cage from day 18 to 23 post-hatching. Excreta samples were collected twice daily from day 18 to 20 in experiment 1 or day 20 to 22 in experiment 2, and ileal digesta were collected on day 21 (experiment 1) or day 23 (experiment 2). The IDE, ME, and MEn (kcal/kg DM) of TDDGS or SDDGS were derived from the regressions of TDDGS-, SDDGS-, or rye-associated, IDE, apparent ME, and apparent MEn intake in kilocalories against the intake of TDDGS, SDDGS, or rye (X, kg DM), respectively. For diets with TDDGS substitution, regression equations were IDE = 12.3 + 3,288X, ME = -3.0 + 2,800X, and MEn = -0.4 + 2,647X. The equations for the SDDGS diets were IDE = -4.8 + 3,247X, ME = -7.6 + 3,210X, and MEn = -7.0 + 3,072X; and those for the rye diets were IDE = 9.5 + 3,002X, ME = 6.3 + 3,053X, and MEn = 4.8 + 2,928X. The IDE contents did not differ between TDDGS and SDDGS whereas the ME and MEn contents were greater (P < 0.05) in the SDDGS than in the TDDGS. In conclusion, the current study provided energy values of the DDGS sources and rye using the regression method. The regression-derived IDE for TDDGS, SDDGS, or rye were 3,288, 3,247, or 3,002 kcal/kg DM, respectively; corresponding ME were 2,800, 3,210, or 3,053 kcal/kg DM. The respective regression-derived MEn for TDDGS, SDDGS, or rye were 2,647, 3,072, or 2,928 kcal/kg DM for broiler chickens.

Energy efficiency and net energy prediction of feed in laying hens

Using accurate nutrient values for ingredients is of vital importance for efficient diet formulation. The net energy (NE) system accounts for the real available amount of feedstuff energy for body maintenance and production as it considers energy dissipated as heat increment. The NE content of diets for pigs and broilers has been estimated from their nutrient contents. However, such estimates have not been made specifically for laying hens. This study reports the development of equations to predict NE for laying hens based on the chemical composition of 16 different diets meeting minimum nutrient specifications but varying in nutrient composition. Heat production and energy metabolism were measured in layers ranging from 32 to 62 weeks of age in closed-circuit calorimetry chambers with 8 replicates per diet in a randomized design. Each replicate consisted of a chamber with 3 layers that were adapted for 4 D to diets and chambers prior to measurement. The measurements included feed intake, metabolizable energy (ME) content, nitrogen balance, egg production, gas exchange, heat production, energy efficiency, and energy partition for a 3-D period. The average AME/GE and NE/AME ratios of the 16 diets were 77 and 74%, respectively. The latter ratio increased with energy efficiency (EE) content and decreased with CP content of diets. The results indicate that diet NE content can be predicted from AME, CP, and EE contents and the NE/AME ratio varied positively with EE and negatively with CP. A validation experiment with 2 diets fed to layers in calorimetry chambers confirmed the estimation from NE prediction equations. In conclusion, NE of diets can be predicted in laying hens from equations based on AME and CP and EE contents in laying hens being similar to those reported in broilers.

Historical flaws in bioassays used to generate metabolizable energy values for poultry feed formulation: a critical review

Dietary energy available to animals is key for formulating feed as it is required for all aspects of the animal's life. In poultry, apparent (AME) and true (TME) metabolizable energy (ME) values have been used for feed formulation with (AMEn or TMEn) or without correction for nitrogen balance. For the past 50 yr, the accuracy of ME has been an ongoing debate, and the comparability of data produced using different bioassay systems is often questionable. Overall, the ingredient matric ME values used in feed formulation are not consistent, and to some extent, confusing. This review was to examine ME data published in the past century to elucidate the accuracy of different bioassay systems and examine the values for accuracy and useability. A variety of flaws are identified in the literature, suggesting a thorough re-thinking of feedstuff ME values currently used in feed formulation and in developing prediction equations. Two protocols, namely multiple linear regression and basal diet substitution methods, are proposed as more accurate bioassays for feedstuff ME values. AME aligns more closely with the actual energy levels of feed ingredients likely available to growing birds, which should be used for poultry feed formulations instead of AMEn. It is suggested that nutritionists need to carefully apply any reported AME values and only use those in formulation practice after careful scrutinizing. Any in vitro, NIR or table values must be calibrated or computed based on the values produced from flawless bioassays so as to apply the derived values accurately. Flaws identified in this literature review can be avoided with care to achieve more accurate AME. However, the assumption that the energy of individual ingredients is additive in a complete diet is still untrue at least under some circumstances. This may require efforts from industry and researchers to investigate relations among the main ingredients in a complete diet so that more accurate formulation can be performed based on the outcomes that may fine-tune the additivity assumption.

Factors affecting energy metabolism and evaluating net energy of poultry feed

Different energy evaluating systems have been used to formulate poultry diets including digestible energy, total digestible nutrients, true metabolizable energy, apparent metabolizable energy (AME), and effective energy. The AME values of raw materials are most commonly used to formulate poultry diets. The net energy (NE) system is currently used for pig and cattle diet formulation and there is interest for its application in poultry formulation. Each energy evaluating system has some limitations. The AME system, for example, is dependent on age, species, and feed intake level. The NE system takes AME a step further and incorporates the energy lost as heat when calculating the available energy for the production of meat and eggs. The NE system is, therefore, the most accurate representation of energy available for productive purposes. The NE prediction requires the accurate measurement of the AME value of feed and also an accurate measurement of total and fasting heat production using nutritionally balanced diets. At present, there is limited information on NE values of various ingredients for poultry feed formulation. The aim of this review is to examine poultry feed energy systems with the focus on the NE system and its development for chickens.

Metabolizable energy of corn, soybean meal and wheat for laying hens

Feed formulation using apparent metabolizable energy (AME) corrected to zero nitrogen retention (AMEn) is widely used by poultry nutritionists. Most available tabulated data are from experiments using adult cockerels or growing broilers. Specific values are rarely available for laying hens. A study was conducted to evaluate AME, AMEn, and AMEs (AME adjusted to 50% nitrogen retention) of corn, soybean meal (SBM) and wheat in laying hens using the reference diet substitution and regression methods. Forty eight 42-wk-old Hy-Line Brown hens were used, 2 birds per cage with six replicates per diet. Test diets contained 30% test ingredient (as is basis) and 65.7% reference diet (as is basis) with limestone, other minerals, vitamins, and amino acids held constant across the reference and test diets. Using the reference diet substitution method, AME values obtained for corn, SBM, and wheat were 3,791, 2,621, and 3,565 kcal/kg (DM), respectively. The corresponding AMEn values were 3,722, 2,496, and 3,479 kcal/kg (DM), and AMEs were 3,784, 2,835, and 3,562 kcal/kg (DM), respectively. Calculation of AME, AMEn, and AMEs of ingredients using regression based on the inclusion rate (DM) of dietary ingredients and reference diet gave identical values to those obtained by the reference diet substitution method. In addition, the measured AMEn values of ingredients using laying hens in this study were close to those calculated from proximate composition using the European Union prediction equation based on adult cockerels.

Nutrient content and digestibility of different batches of wheat distillers dried grains with solubles for laying hens

1. Four batches of wheat distillers dried grains with solubles (DDGS) produced by a single production plant were used to investigate variation in digestible energy (DE) and nutrient digestibility for laying hens. 2. A total of 144 Hy-Line Brown laying hens were allocated to eight treatment groups in replicates of six. Experimental diets were prepared by replacing the basal feed with either 150 g/kg or 300 g/kg of each batch of DDGS. 3. Chemical analysis of the DDGS showed variation between the different batches. Largest coefficients of variation were observed for starch (0.546) and total soluble non-starch polysaccharides (NSP; 0.276). 4. Digestible energy and the nutrient digestibility of each diet was measured using the ileal collection technique. Data were statistically analysed as a blocked 2 × 4 factorial design analysis of variance (ANOVA). 5. Variability between the different diets were observed for digestible energy and the digestibility of certain nutrients (P < 0.05). 6. The observed differences in energy utilisation and nutrient digestibility in laying hens suggested that the feeding quality of diets containing different wheat DDGS batches produced by a single production plant may still have large variation.

Net energy prediction and energy efficiency of feed for broiler chickens

Global consumption of chicken meat has increased at a faster rate than any other animal protein source, and thus refinements in energy formulation techniques for feed have continued to gain importance. Formulation of animal feed based on net energy (NE) has been implemented in ruminants and pigs but not in poultry. A closed-circuit respiratory calorimetry system was employed on 25- to 28-day-old broilers fed 19 diets formulated with varying nutrient composition to produce equations to predict NE and apparent metabolizable energy (AME) efficiency of feed for broiler chickens. Performance, energy and N balance, respiratory quotient, and energy utilization were measured in the birds. Linear regression analysis was performed to generate prediction equations for dietary energy content and AME efficiency. The NE content was positively related to AME and ether extract, but negatively to crude protein. The study generated equations that can accurately predict NE, and NE/AME using AME value and chemical composition of feeds. The NE prediction equations were further validated on a separate set of diets with high correlation (r = 0.99) and accuracy. The outcomes are an important step for the broiler industry to adapt to an NE system in place of AME systems for the formulation of broiler chicken feeds following robust validation experiments.

ECOALIM: A Dataset of Environmental Impacts of Feed Ingredients Used in French Animal Production

Feeds contribute highly to environmental impacts of livestock products. Therefore, formulating low-impact feeds requires data on environmental impacts of feed ingredients with consistent perimeters and methodology for life cycle assessment (LCA). We created the ECOALIM dataset of life cycle inventories (LCIs) and associated impacts of feed ingredients used in animal production in France. It provides several perimeters for LCIs (field gate, storage agency gate, plant gate and harbour gate) with homogeneously collected data from French R&D institutes covering the 2005-2012 period. The dataset of environmental impacts is available as a Microsoft® Excel spreadsheet on the ECOALIM website and provides climate change, acidification, eutrophication, non-renewable and total cumulative energy demand, phosphorus demand, and land occupation. LCIs in the ECOALIM dataset are available in the AGRIBALYSE® database in SimaPro® software. The typology performed on the dataset classified the 149 average feed ingredients into categories of low impact (co-products of plant origin and minerals), high impact (feed-use amino acids, fats and vitamins) and intermediate impact (cereals, oilseeds, oil meals and protein crops). Therefore, the ECOALIM dataset can be used by feed manufacturers and LCA practitioners to investigate formulation of low-impact feeds. It also provides data for environmental evaluation of feeds and animal production systems. Included in AGRIBALYSE® database and SimaPro®, the ECOALIM dataset will benefit from their procedures for maintenance and regular updating. Future use can also include environmental labelling of commercial products from livestock production.

Assessment of caecal parameters in layer hens fed on diets containing wheat distillers dried grains with solubles

There is much interest in quantifying the nutritional value of UK wheat distillers dried grains with solubles (W-DDGS) for livestock species. A study was designed to evaluate caecal parameters (pH, short chain fatty acids (SCFAs) and bacterial diversity) in layer hens fed on balanced diets containing graded concentrations of W-DDGS. A total of 32 layer hens (Bovans Brown strain at 27 weeks of age) were randomly allocated to one of 4 dietary treatments containing W-DDGS at 0, 60, 120 or 180 g/kg. Each treatment was fed to 8 replicate individually housed layer hens over a 5-d acclimatisation period, followed by a 4-week trial. Individual feed intakes were monitored and all eggs were collected daily for weeks 2, 3 and 4 of the trial, weighed and an assessment of eggshell "dirtiness" made. All hens were culled on d 29 and caecal pH and SCFAs measured. Polymerase chain reaction denaturing gradient gel electrophoresis of the bacterial 16 S rDNA gene was used to assess total bacterial diversity of luminal caecal content from hens fed the 0 and 180 g W-DDGS/kg diets. Unweighted pair group method with arithmetic mean (UPGMA) dendrograms were generated from DGGE banding patterns. Increasing W-DDGS dietary concentrations resulted in a more acidic caecal environment. Caecal SCFAs were unaffected by diet aside from a quadratic effect for molar proportions of isobutyric acid. Diversity profiles of the bacterial 16S rRNA gene from luminal caecal contents were unaffected by W-DDGS inclusion. The results of the current study suggest that W-DDGS can be successfully formulated into nutritionally balanced layer diets (supplemented with xylanase and phytase) at up to 180 g/kg with no detrimental effects to the caecal environment.

Metabolizable energy content of wheat distillers' dried grains with solubles supplemented with or without a mixture of carbohydrases and protease for broilers and turkeys

In this study, 2 experiments were conducted to determine the AME and AMEn of wheat distillers' dried grains with solubles (DDGS) without or with supplementation of an enzyme mixture containing xylanase, amylase, and protease (XAP) in broilers and turkeys. One hundred twenty-six male Ross 308 broilers (Experiment 1) or 126 male BUT 10 turkeys (Experiment 2) were offered a nutrient-adequate diet from d 1 to 14. On d 14, birds in each experiment were allocated to 6 treatments consisting of 3 levels of wheat-DDGS (0, 300, or 600 g/kg) and 2 levels of XAP (0 or 250 mg/kg diet) in a randomized complete block design. The AME or AMEn content of wheat-DDGS was determined from the slope of regression of wheat-DDGS-associated energy intake (kilocalories) against wheat-DDGS intake (kilograms). In Experiment 1, wheat-DDGS inclusion in the diets linearly decreased (P<0.05) DM retention, AME, and AMEn, irrespective of XAP supplementation. The AME of wheat-DDGS without or with XAP for broilers was 3,587 or 3,700 kcal/kg DM, respectively, and AMEn was 3,356 and 3,459 kcal/kg DM for wheat-DDGS without and with XAP, respectively. In Experiment 2, wheat-DDGS inclusion in the diet linearly decreased (P<0.05) DM retention irrespective of XAP supplementation. Diet AME and AMEn linearly decreased (P<0.05) as the level of wheat-DDGS increased in the diets without added XAP, whereas there was no effect of increasing wheat-DDGS level on dietary AME or AMEn in the XAP-supplemented diets. The AME of wheat-DDGS without and with supplemental XAP for turkeys were 3,355 and 3,558 kcal/kg DM, respectively, and AMEn was 3,109 and 3,294 kcal/kg DM, respectively, for wheat-DDGS without and with XAP. Supplemental XAP increased (P>0.05) the AME and AMEn of wheat-DDGS for broilers and turkeys by up to 6%. It was concluded that wheat-DDGS is a valuable source of AME for broilers and turkeys.

Nitrogen-corrected True Metabolizable Energy and Amino Acid Digestibility of Chinese Corn Distillers Dried Grains with Solubles in Adult Cecectomized Roosters

This study was conducted to evaluate chemical composition, nitrogen-corrected true metabolizable energy (TMEn) and true amino acids digestibility of corn distillers dried grains with solubles (DDGS) produced in China. Twenty five sources of corn DDGS was collected from 8 provinces of China. A precision-fed rooster assay was used to determine TMEn and amino acids digestibility with 35 adult cecectomized roosters, in which each DDGS sample was tube fed (30 g). The average content of ash, crude protein, total amino acid, ether extract, crude fiber and neutral detergent fiber were 4.81, 27.91, 22.51, 15.22, 6.35 and 37.58%, respectively. TMEn of DDGS ranged from 1,779 to 3,071 kcal/kg and averaged 2,517 kcal/kg. Coefficient of variation for non-amino acid crude protein, ether extract, crude fiber and TMEn were 55.0, 15.7, 15.9 and 17.1%, respectively. The average true amino acid digestibility was 77.32%. Stepwise regression analysis obtained the following equation: TMEn, kcal/kg = -2,995.6+0.88×gross energy+49.63×a* (BIC = 248.8; RMSE = 190.8; p<0.01). Removing gross energy from the model obtained the following equation: TMEn, kcal/kg = 57.88×ether extracts+87.62×a* (BIC = 254.3, RMSE = 223.5; p<0.01). No correlation was found between color scores and lysine true digestibility (p>0.05). These results suggest that corn DDGS produced in China has a large variation in chemical composition, and gross energy and a* value can be used to generate TMEn predict equation.

Apparent metabolizable energy and prediction equations for reduced-oil corn distillers dried grains with solubles in broiler chicks from 10 to 18 days of age

An experiment consisting of 2 identically designed trials was conducted to determine the nutrient composition and AMEn content of distillers dried grains with solubles (DDGS) to develop prediction equations for AMEn in broilers. Fifteen samples of DDGS ranging in ether extract (EE) from 3.15 to 13.23% (DM basis) were collected from various dry-grind ethanol plants and were subsequently fed to broiler chicks to determine AMEn content. A corn-soybean meal control diet was formulated to contain 15% dextrose, and test diets were created by mixing the control diet with 15% DDGS at the expense of dextrose. In each trial, 672 male Ross × Ross 708 chicks were housed in grower battery cages with 7 birds per cage (0.06 m(2)/bird) and received a common starter diet until 10 d of age. Each cage was randomly assigned to 1 of 16 dietary treatments, with 6 replicate pens per treatment. Experimental diets were fed over a 6-d acclimation period from 10 to 16 d of age, followed by a 48-h total excreta collection period. Gross energy (GE) and CP of the experimental diets and excreta were determined to calculate AMEn for each DDGS sample. On a DM basis, AMEn of the 15 DDGS samples ranged from 1,869 to 2,824 kcal/kg. Analyses were conducted to determine the GE, CP, EE, DM, starch, total dietary fiber (TDF), neutral detergent fiber (NDF), acid detergent fiber (ADF), and ash content of the DDGS samples. Stepwise regression resulted in the following best-fit equation for AMEn (DM basis) based on the adjusted coefficient of determination (R(2)adj), SE, and prediction error sum of squares (PRESS): AMEn, kcal/kg = -12,282 + (2.60 × GE) + (89.75 × CP) + (125.80 × starch) - (40.67 × TDF; R(2)adj = 0.86; SE = 98.76; PRESS = 199,819; P ≤ 0.001). These results indicated that the composition of DDGS with variable EE content may be used to predict AMEn in broiler chicks.

The correlationship between the metabolizable energy content, chemical composition and color score in different sources of corn DDGS

Background

This study was conducted to evaluate the apparent metabolizable energy (AME) and true metabolizable energy (TME) contents in 30 sources of corn distillers dried grains with solubles (DDGS) in adult roosters, and establish the prediction equations to estimate the AME and TME value based on its chemical composition and color score.

Methods

Twenty-eight sources of corn DDGS made from several processing plants in 11 provinces of China and others imported from the United States. DDGS were analyzed for their metabolizable energy (ME) contents, measured for color score and chemical composition (crude protein, crude fat, ash, neutral detergent fiber, acid detergent fiber), to predict the equation of ME in DDGS. A precision-fed rooster assay was used, each DDGS sample was tube fed (50 g) to adult roosters. The experiment was conducted as a randomized incomplete block design with 3 periods. Ninety-five adult roosters were used in each period, with 90 being fed the DDGS samples and 5 being fasted to estimate basal endogenous energy losses.

Results

Results showed that the AME ranged from 5.93 to 12.19 MJ/kg, TME ranged from 7.28 to 13.54 MJ/kg. Correlations were found between ME and ash content (-0.64, P < 0.01) and between ME and yellowness score (0.39, P < 0.05) of the DDGS samples. Furthermore, the best-fit regression equation for AME content of DDGS based on chemical composition and color score was AME = 6.57111 + 0.51475 GE - 0.10003 NDF + 0.13380 ADF + 0.07057 fat - 0.57029 ash - 0.02437 L (R² = 0.70). The best-fit regression equation for TME content of DDGS was TME = 7.92283 + 0.51475 GE - 0.10003 NDF + 0.13380 ADF + 0.07057 fat - 0.57029 ash - 0.02437 L (R² = 0.70).

Conclusions

This experiment suggested that measuring the chemical composition and color score of a corn DDGS sample may provide a quality parameter for identifying corn DDGS sources energy digestibility and metabolizable energy content.

Feeding Wheat Distillers Dried Grains with Solubles (DDGS) to Laying Hens and its Effect on Performance and Egg Quality

The purpose of this experiment was to determine the effect of wheat DDGS as a feed ingredient on the performance of laying hens and their egg quality. ISA Brown laying hens were administered a feed mixture containing 15% (E1) or 20% (E2) wheat DDGS for 12 weeks. The hens from the control group (C) received a standard diet based on soybean meal as the main protein source only. Laying performance (laying %), average egg weight (g), average daily feed intake (g/hen), and feed conversion ratio (kg/kg eggs) were recorded over the study period. Egg quality traits (egg weight, thick albumen quality, yolk colour, yolk percentage, shell percentage and shell thickness) were evaluated twice: before the start and at the end of the experiment. There was no effect of dietary DDGS on laying performance or on feed intake. The average egg weight was significantly lower in both experimental groups and the feed conversion ratio was lower compared to the control group. Dietary wheat DDGS did not affect the main egg quality parameters except for thick albumen quality. Eggs from hens fed the diet with DDGS had higher values of Haugh unit than those from the control hens. These results suggest that wheat DDGS can be used in amounts of up to 20% as a component of feed mixtures for flocks of laying hens.