Digestible Amino Acid Content Research Articles

A Three-Year Study on the Nutritional Composition and Occurrence of Mycotoxins of Corn Varieties with Different Transgenic Events Focusing on Poultry Nutrition.

Corn is one of the most produced cereals in the world and plays a major role in poultry nutrition. As there is limited scientific information regarding the impact of transgenic technology on the quality and nutrient composition of the grains, this study investigated the effect of three major transgenic corn varieties-VT PRO3®, PowerCore® ULTRA, and Agrisure® Viptera 3-on the field traits, nutrient composition, and mycotoxin contamination of corn grains cultivated in southern Brazil during three consecutive harvests. VT PRO3®, while demonstrating superior crop yield, showed susceptibility to mycotoxins, particularly fumonisins. In contrast, PowerCore® ULTRA, with the lowest yield, consistently exhibited lower levels of fumonisins. VT PRO3® had higher AMEn than the other varieties, while PowerCore® ULTRA had the highest total and digestible amino acid contents over the three years. The study's comprehensive analysis reveals the distinct impact of transgenic corn technologies on both productivity and nutritional levels. Balancing the crops yield, mycotoxin resistance, and nutritional content of corn is crucial to meet the demands of the poultry feed industry. Such insights are essential for decision-making, ensuring sustainability and efficiency in agricultural production as well as meeting the demands of the poultry industry.

PSIII-17 Evaluation of Cheese co-Products in Comparison with Specialty Proteins on Growth Performance of Weaned Pigs

Abstract Plant protein, animal protein, and milk protein are common protein sources in nursery diets. To ensure growth performance of pigs and profitability of feeding programs, specialty protein ingredients are strategically selected by nutritionists primarily based on energy value, digestible amino acid (AA) content, nutrient variability, and cost. Indeed, standardized ileal digestibility of AA and metabolizable energy are greater in cheese co-products than fishmeal or enzymatic-treated soybean meal (ESBM). Therefore, two experiments were conducted to determine if replacing specialty protein sources with a novel cheese co-product in nursery diets could improve growth variables and profitability. In experiment 1, a total of 540 pigs (PIC 800 x Camborough; 7.1 kg) were blocked by body weight and allotted to 3 treatments, 10 replicates per treatment, and 18 pigs per pen. The three dietary treatments were a control diet containing ESBM and microbial biomass (MB) or 5% of cheese co-product from manufacturer A or B added to the basal diet with replacement of ESBM and MB. In experiment 2, a total of 1,080 pigs (PIC 800 x Fast 276; 6.7 kg) were blocked by body weight and allotted to 4 treatments, 15 replicates per treatment, and 18 pigs per pen. The four treatments were a control diet with ESBM and MB, control with 5% of cheese co-product by replacing ESBM; control with 0.5% of functional protein; control with 4% of bovine plasma. All experimental diets were formulated on an equal SID Lys basis and a common diet was provided after approximately 3 weeks post-weaning. Data were analyzed using generalized linear mixed models with treatment as a fixed effect and block as a random effect. Results from experiment 1 showed that pigs fed cheese co-products regardless of the source had greater ADG (P < 0.05) by 4.4% than those fed control. Results from experiment 2 showed that pigs fed cheese co-product had greater (P < 0.05) intake in week 2 and week 3, which resulted in an overall increase in feed intake by 7.5% compared with those fed functional protein. However, there were no difference in overall gain, ADG, and feed efficiency during the entire 40-day study. Economic assessment showed that pigs fed cheese co-products had better income over feed cost than control in experiment 1 and had an equivalent income over feed cost compared with control in experiment 2. These results suggest that the novel cheese co-products can effectively substitute for ESBM and other specialty proteins in nursery diets and provide some flexibility to substitute expensive protein sources without jeopardizing growth and profitability.

Influence of partial replacement of ground barley with whole barley and exogenous enzyme supplementation in pelleted diets on growth performance, nutrient utilisation and foregut development in broiler starters

A 3 × 2 factorial arrangement of treatments, evaluating three inclusion levels of whole barley (WB; 0, 141, 282 g/kg) in a barley-based diet and two levels of carbohydrase (Carb; 0 and 0.15 g/kg of feed), was used. The AMEn and standardised digestible amino acid contents of the test barley were used in formulating the basal diet. Whole barley was added to the diet at the expense of ground barley (GB; 3.0 mm sieve size). The diets contained 5.0 g/kg titanium dioxide as an inert marker. Each of the six experimental diets was pelleted and offered ad libitum to six replicate cages (eight birds/cage). Body weights and feed intake were recorded weekly throughout the 21-d trial. The AMEn was determined using the classical total excreta collection method (17–20 d). On d-21, ileal digesta were collected from the terminal ileum to determine the coefficient of apparent ileal digestibility of nutrients. Jejunal digesta were collected for the determination of intestinal digesta viscosity. There was no significant (P > 0.05) interaction between WB and Carb for any measured parameter. Compared to the birds fed GB diets, those fed WB at 141 g/kg had a higher (P < 0.05) weight gain by 36 g/bird, with no effect on the feed intake or feed efficiency. The inclusion of WB tended (P = 0.058) to enhance N digestibility from 0.741 in GB diets to 0.775 in diets with 282 g/kg WB. Irrespective of Carb supplementation, compared to the GB diet, WB inclusion at 141 and 282 g/kg improved (P < 0.001) starch digestibility (by 3.6 % and 5.7 %, respectively) and AMEn (by 1.85 % and 2.89 %, respectively). These improvements were not associated with any impact (P > 0.05) on gizzard development. Jejunal digesta viscosity was not influenced (P > 0.05) by WB inclusion. Adding Carb increased starch digestibility and energy utilisation by 2.24 % and 0.12 MJ/kg, respectively, possibly due to 0.35 cP reduction in jejunal digesta viscosity (P < 0.05) by the supplemental Carb. Overall, WB could be included in barley-based broiler starter diets up to 282 g/kg of diet with no adverse effects on performance.

Impacts of Age, Genotype and Feeding Low-Protein Diets on the N-Balance Parameters of Fattening Pigs

The effects of feeding low-protein (LP) diets and the age and genotype of fattening pigs were evaluated in an N-balance trial. Sixty weaned piglets of two genotypes were allotted to three different diets. Besides the control diets for the crossbred Topigs 20 × DanBred Duroc (TD) and Hungarian Large White (HLW) pigs, two LP diets were fed containing 1.5 (T1.5) and 3% (T3) less dietary protein than the control. The LP diets were supplemented with crystalline lysine, threonine, tryptophan, and methionine to equalize their digestible amino acid contents. Starter diets were fed between 20–30, grower I between 30–40, grower II between 40–80 and finisher between 80–110 kg live weights. Pigs were kept in floor pens, with 10 animals per pen. In all phases, six pigs with similar live weight were placed into individual balance cages and in the frame of a seven-day long balance trial, the daily N-intake, fecal and urinary N-excretion were measured. From the data N-digestibility, the total ammoniacal nitrogen (TAN) and N-retention were calculated. All the investigated main factors, the genotype and age of pigs and the protein content of the diets had significant effects on the N-balance of fattening pigs. The determinacy of the factors depended on the investigated parameter. Fecal N-excretion and N-digestibility were steadier compared with the urinary N-exertion and TAN percentage. N-digestibility increased and the urinary N-excretion decreased when LP diets were fed. The urinary N-decreasing effect of LP diets was not linear. Compared with the control (19.6 gN/day), T1.5 treatment resulted in 14.5, treatment T3 in 12.4 g daily urinary N-excretion. The TAN and the N-retention of HLW pigs were more favorable than those of TD pigs. Based on our results, it can be concluded that the accuracy of the nitrogen and TAN excretion values of pigs, used in the calculation of the national NH3 inventories, could be improved if the genotype, the more detailed age categories and the different protein levels of feeds are considered.

Nutritive evaluation, metabolisable energy and digestible amino acid contents of different indigenous feedstuff for Nile tilapia (Oreochromis niloticus).

Three trials were executed to examine the nutritive profile, metabolisable energy and digestible amino acid (AA) contents of four indigenous feed ingredients including wheat (W), wheat middling (WM), canola meal (CM) and rapeseed meal (RSM) in Nile tilapia. Three samples of each test ingredient were collected from three different locations of Multan (MUL) and Sukkar (SKR), of Pakistan. The collected three samples were pooled thereafter to make a homogenous/ representative sample of each test ingredient from a particular study site. Nutrients composition, AA and energy digestibility of these indigenous ingredients were evaluated by using laboratory analyses and fish studies. Proximate analysis indicated variations in some of the nutrients due to location (p < 0.05). Differences were also observed in some AA including arginine, lysine, serine, cysteine, glutamic and aspartic acids, histidine, valine and glycine contents of these ingredients (p < 0.05). Digestibility of leucine, glycine and glutamic acid was higher (p < 0.05) in RSM from MUL. Among W samples from MUL, AA digestibility for lysine, threonine, and aspartic acid was higher (p < 0.05). Crude protein, arginine, alanine, serine, and aspartic acid had higher digestibility (p < 0.05), whereas digestibility was lower (p < 0.05) for threonine, valine and tyrosine in RSM from MUL. Metaboliseable energy contents did not differ among W, WM, CM and RSM regarding their origin (p > 0.05). The results indicated that nutritional profiles and their digestibility indices vary with the location for Nile tilapia.

Reducing environmental impacts of feed using multiobjective formulation: What benefits at the farm gate for pig and broiler production?

Feed production is the main contributor to several environmental impacts of livestock. To decrease environmental impacts of feed, those of feedstuffs should be considered during formulation. In particular, multiobjective feed formulation (MOF) can help reduce several environmental impacts simultaneously while keeping any increase in feed price moderate. The objective of this study was to assess environmental benefits of MOF at the farm gate for fattening pigs and broilers. For pigs, three feeding strategies were tested: classic 2-phase (2P), 2-phase with lower net energy content (2P−), and multiphase (MP). For broilers, two strategies were tested: classic 3-phase (3P) and 3-phase with higher digestible amino acid contents and lower metabolisable energy content (3P+). Diets were formulated using both least-cost formulation (LCF) and MOF, yielding six pig scenarios and four broiler scenarios. Environmental impacts at the farm gate were estimated using a modelling approach based on life cycle assessment. Indicators for six impact categories were then calculated: climate change (CC), cumulative non-renewable energy demand (CEDNR), acidification (AC), eutrophication (EU), land occupation (LO), and phosphorus demand (PD). As expected, MOF had lower farm-gate impacts than LCF (as much as −13%), but the degree of decrease varied by feeding strategy and impact. For pigs, MOF was equally effective in all strategies at reducing PD (−6 to −9%) and AC (−2%). In contrast, MOF was more effective in 2P and 2P− at decreasing CC (−5% to −7%), LO (−9% to −13%) and EU (−6% to −8%) than in MP (CC: −2%; LO: −4%; EU: −3%). The benefit of MOF was found greater in 2P (−7%) than in other pig strategies for CEDNR (−3 to +0%). For broilers, MOF was equally effective in both strategies tested at decreasing PD (−12%), AC (−2%), and EU (−4%). For CC and CEDNR, MOF was more effective in 3P (CC: −9%; CEDNR: −11%) than 3P+ (−6% for both impacts), but not for LO (+3% in 3P vs −1% in 3P+). These differences were due mainly to differences in animal performance (especially feed conversion ratio) among the strategies tested. Finally, in all scenarios, gross margin at the farm gate decreased with MOF comparatively to LCF (pigs: −3% to −11%); broilers: −7% to −11%). These results demonstrate the importance of comprehensive economic and environmental optimisation of feeding strategies by simultaneously considering feed impacts, animal performance, and manure management. To do so, further research is therefore required to develop new modelling tools.

Standardized ileal amino acid digestibility of protein sources for broiler chickens is influenced by the feed form

The aim of present study was to determine the influence of the feed form (FF) on standardized ileal digestibility (SID) of nitrogen (N) and amino acids (AA) in 3 protein sources (PS) for broiler chickens. Six diets were tested in a 3 × 2 factorial arrangement of treatments involving 3 PS (meat and bone meal [MBM], soybean meal [SBM], and canola meal [CM]) in mash and pelleted forms. The basal endogenous N and AA losses were determined by offering a N-free diet in the mash form. From day 1 to 18, the birds were offered a broiler starter diet. The diets and the N-free diet were randomly assigned to 6 replicate cages (8 birds per cage) and fed from day 19 to 23. The ileal digesta were collected on day 23. The SID of N was higher (P < 0.05) in SBM followed by MBM and CM. The average SID of AA in SBM and MBM were similar (P > 0.05), and greater (P < 0.05) than that in CM. The FF had no influence (P > 0.05) on the SID of indispensable AA, the only exception being His, which was reduced (P < 0.05) by pelleting. Pelleting, however, resulted in reduction (P < 0.001) in the SID of all dispensable AA and average of AA. The AA most affected by pelleting was Cys, with a 15.4% decrease in the SID. The standardized ileal digestible contents of protein and the average of indispensable AA and dispensable AA were higher in MBM than in SBM, with CM being the lowest. Pelleting decreased (P < 0.05) the digestible protein and total digestible AA contents. These findings reveal that the FF has a substantial impact on AA digestibility estimates of feed ingredients and it must be considered in AA digestibility assays of ingredients with high protein and AA contents.

Standardized ileal digestible amino acid contents in flaxseed and flaxseed meals fed to growing–finishing pigs

A total of 10 cannulated barrows with an average body weight of 55.99 ± 3.73 kg were assigned to test diets containing either full-fat flaxseed (FFS), expeller-pressed flaxseed meal (expeller-FM), or solvent-extracted flaxseed meal (solvent-FM). The standardized ileal digestibility (SID) of methionine and threonine was higher (P &lt; 0.05) in FFS than in expeller-FM. Similarly, the SID of crude protein (CP) and threonine was higher (P &lt; 0.05) in FFS than that in solvent-FM. However, expeller-FM and solvent-FM had greater (P &lt; 0.05) contents of SID CP, arginine, leucine, phenylalanine, aspartic acid, glutamic acid, and serine than FFS.

Prediction of the total and standardized ileal digestible amino acid contents from the chemical composition of soybean meals of different origin in broilers

The objective of this experiment was to determine total amino acid (TAA) content, standardized ileal digestibility (SID) of crude protein, and standardized ileal amino acid digestibility in 9 sources of soybean meal (SBM) of different origin and to subsequently establish equations for predicting the TAA content and concentration of standardized ileal digestible amino acids (SIDAA) based on their protein content and other proximate components. Concentration of SIDAA of the samples was also predicted using TAA values. A total of 160 1-day-old male broiler chicks were randomly assigned to 10 dietary treatments consisted of 9 semipurified diets containing one SBM (200 g of crude protein/kg) as the only source of dietary amino acid (AA) and one N-free diet to determine endogenous ileal AA flow. The birds were fed with a standard diet from 0 to 18 D of age, and experimental diets were fed from 19 to 24 D of age. The fitness of the models of the study was tested using the adjusted coefficient of determination (R2) value, P-value regression and coefficients, and standard error of prediction (SEP). The coefficient of SID for Lys and Cys among SBM varied from 86.7 to 96.3 and 74.1 to 89.3, respectively, with significant difference (P < 0.05). In equations based on protein content, the adjusted R2 value ranged from 40.7 (Ile) to 99.6 (Met) and 37.2 (Met + Cys) to 99.6 (Met) for TAA content and concentration of SIDAA, respectively. Inclusion of other proximate components of test samples (e.g., crude fiber, neutral detergent fiber, acid detergent fiber, ash, gross energy, and so on) into the regression equation increased the adjusted R2 value and decreased the SEP. The results of linear regression revealed that it is possible to satisfactorily estimate the TAA content and concentration of SIDAA of SBM through its protein content and other proximate components, but the prediction equations based on other proximate components were more accurate in terms of reflecting the measured results; however, additional time and costs were associated with this approach. It is also possible to estimate the concentration of SIDAA through TAA values with reasonable accuracy and lower SEP.

Relationship between chemical composition and standardized ileal digestible amino acid contents of corn grain in broiler chickens

This experiment was conducted to evaluate the chemical composition and standardized ileal amino acid digestibility of corn grain and to use these data to develop prediction equations for estimating total amino acids (TAAs) and standardized ileal digestible amino acids (SIDAAs) for broiler chickens. Four types of corn grains were obtained from different origins (Brazil, Ukraine, Russia, and Iran). Eighty-day-old Ross 308 male broiler chicks were fed a standard diet until day 18, and experimental diets were fed from 19 to 24 D of age. Five dietary treatments consisted of 4 semi-purified diets containing corn from each origin as the only source of amino acid (AA) and a N-free diet for determination of basal endogenous AA losses. Assay diets contained 939 g of test corn/kg. The concentration of crude protein and gross energy ranged from 7.58 to 8.39% (coefficient of variation [CV] = 4.72%) and 4,121 to 4,621 kcal/kg (CV = 5.09%), respectively. There was significant variation among the 4 corn grains in standardized ileal digestibility (SID) for CP, Phe, Leu, Asp, Glu, Ser, Gly, Ala, and Tyr (P ≤ 0.05). The results of linear regression showed that linear prediction equations based on protein content can be used to predict the TAA and SIDAA contents (e.g., TLys = 0.041 × CP, adj R2 = 95.9, standard error of prediction [SEP] = 0.05; SIDLys = 0.0356 × CP, adj R2 = 96, SEP = 0.051). Inclusion of other proximate components of test samples into the regression equation increased the R2 value and decreased the SEP value (e.g., TLys = 0.329 × crude fiber [CF] ‒ 0.209 × Ash, adj R2 = 99.9, SEP = 0.005; SIDLys = ‒1.1591 + 0.836 × CF ‒ 0.055 × Ash, adj R2 = 99.9, SEP = 0.001). The concentration of TAA and SIDAA was highly correlated (adj R2 > 89%) for most AA and showed that the amount of SIDAA could be predicted from its total concentration with a high degree of accuracy (e.g., SIDLys = 0.0023 + 0.861 × TLys, adj R2 = 99.9, SEP = 0.0001). In conclusion, this in vitro assays and equations accurately predicted TAA and SIDAA corn grain samples for broiler chickens and can serve as a reference analysis to develop calibration equations for rapid feed quality evaluation methods such as near-infrared reflectance spectroscopy.

The effect of graded inclusions of waxy starch hull-less barley and a multi-component exogenous carbohydrase on the growth performance, nutrient digestibility and intestinal morphometry of broiler chickens

ABSTRACT 1. A 21-d experiment was conducted to investigate the effect of graded inclusions of waxy starch hull-less (WSHL) barley and a multi-component exogenous carbohydrase on the growth performance, nutrient digestibility and intestinal morphometry of broiler chickens. Five levels of WSHL barley inclusion (0, 65, 130, 195 and 260 g/kg) in a wheat-based diet, and two levels of enzyme supplementation (0 and 150 g/tonne of feed) were evaluated in a 5 × 2 factorial arrangement of 10 dietary treatments. All diets were equivalent in metabolisable energy and digestible amino acid content. A total of 400, one-d-old male broilers (five cages/treatment; eight birds/cage) were used in the experiment. 2. Regardless of enzyme supplementation, feed intake declined (P < 0.001) with increasing inclusion of WSHL barley. Increasing levels of WSHL barley (P < 0.001) and supplemental enzyme (P < 0.01) increased gain to feed ratio. 3. Birds fed diets with 0 g/kg WSHL barley showed the lowest (P < 0.001 to 0.01) digestibility for all nutrients except starch. Only starch digestibility was improved (P < 0.05) by enzyme supplementation. The nitrogen-corrected apparent metabolisable energy improved with increasing inclusion of WSHL barley (P < 0.001) and supplemental enzyme (P < 0.001). Increasing inclusion of WSHL barley increased the relative weight of gizzard (P < 0.001) and reduced jejunal digesta viscosity (P < 0.01). Supplemental enzyme (P < 0.001) reduced digesta viscosity. 4. All levels of WSHL barley inclusion improved digestibility of dry matter, nitrogen and fat, whilst energy utilisation improved at inclusions of 130 g/kg WSHL and above, probably due to lowered digesta viscosity and better development of the gizzard. Gain to feed ratio, starch digestibility, energy utilisation and jejunal digesta viscosity can benefit from carbohydrase supplementation in wheat-based diets, regardless of barley inclusion level.

Evaluation of energy and amino acids of brown rice and its effects on laying performance and egg quality of layers.

Two experiments were conducted to determine apparent metabolizable energy (AME), nitrogen-corrected AME (AMEn), and ileal digestible amino acid (AA) content of brown rice (BR) and to investigate the effect of dietary supplementation of BR on laying performance and egg quality of laying hens. In Exp. 1, 72 Hy-line Brown layers (49-week-old) were allocated to two treatments using a completely randomized block design, and each treatment included six cages per treatment and six hens per cage. A semi-purified diet was formulated to include BR as the sole source of AA and energy and an N-free diet was used to determine basal endogenous loss of AA. The hens were fed a commercial layer diet for adaptation to the experimental environment and diet for 7 days from d 0, and then fed experimental diets for 5 days from d 7. Excreta were collected from d 10 to 11 and ileal digesta were collected on d 12. On a dry matter (DM) basis, the AME and AMEn of BR was determined at 3,773 and 3,729 kcal/kg, respectively. The apparent ileal digestibility (AID) of BR ranged from 32.7% for Thr to 73.7% for Arg. The range of the standardized ileal digestibility (SID) value was between 79.4% for Met and 96.6% for Lys. In Exp. 2, 252 Hy-line Brown layers (44-week-old) were divided into four groups, comprising seven replicates of nine birds each and assigned to four experimental diets containing 0 (Control), 5%, 10%, or 15% BR for 5 weeks. The BR-containing diets were formulated to be equal in the content of AMEn and digestible AA to those of the diet without BR. No significant differences were observed in laying performances. Egg quality and blood profiles were not linearly or quadratically affected by dietary treatments. These results suggest that up to 15% BR can be included into layer feed without any adverse effects on laying performance and egg quality, if its energy and digestible AA values are well evaluated.

Growth performance and nutrient digestibility of growing and finishing pigs fed multienzyme-supplemented low-energy and -amino acid diets.

A study was conducted to determine the effects of supplementing corn–soybean meal-based diets with a multienzyme on growth performance, bone mineralization, apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of nutrients of growing pigs. A total of 276 pigs (body weight [BW] = 33.99 ± 4.3 kg) were housed by sex in 45 pens of 6 or 7 pigs and fed 5 diets (9 pens/diet) in a randomized complete block design. Diets were positive control (PC); and negative control 1 (NC1) or negative control 2 (NC2) without or with multienzyme. The multienzyme used supplied at least 1,800, 1,244, 6,600, and 1,000 units of xylanase, β-glucanase, arabinofuranosidase, and phytase per kilogram of diet, respectively. The PC diet was adequate in all nutrients according to NRC recommendations and had greater digestible P content than NC1 or NC2 diet by 0.134 percentage points. The PC diet had greater net energy (NE) and standardized ileal digestible amino acids (AA) content than NC1 diet by 3%, and than NC2 diet by 5%. The diets were fed in 4 phases based on BW: Phase 1: 34–50 kg; Phase 2: 50–75 kg; Phase 3: 75–100 kg; and Phase 4: 100–120 kg. Nutrient digestibility and bone mineralization were determined at the end of Phase 1. Overall (34–120 kg BW), pigs fed the PC and NC1 diets did not differ in average daily gain (ADG) and average daily feed intake. Pigs fed NC2 diet had lower (P < 0.05) ADG and gain-to-feed ratio (G:F) than those fed PC diet. Pigs fed PC diet had greater (P < 0.05) bone ash content and ATTD of P than those fed NC1 diet. The ATTD of GE for PC diet was greater (P < 0.05) than that for NC2 diet, and tended to be greater (P < 0.10) than that for NC1 diet. Multienzyme interacted (P < 0.05) with negative control diet type on overall ADG and AID of GE such that multienzyme did not affect overall ADG and AID of GE for the NC1 diet, but increased (P < 0.05) overall ADG and AID of GE for NC2 diet by 5.09 and 8.74%, respectively. Multienzyme did not interact with negative control diet type on overall G:F, bone ash content, AID of AA, and ATTD of nutrients. Multienzyme increased (P < 0.05) overall G:F, AID of methionine, ATTD of GE and P, and tended to increase (P = 0.056) bone ash content. The ADG, bone ash content, and ATTD of GE and P for the multienzyme-supplemented diets were similar to (P > 0.10) PC diet. Thus, NE and digestible AA and P can be lowered by ≤5% in multienzyme-supplemented diets without effects on growth performance and bone ash of pigs.

Effects of feeding high-protein corn distillers dried grains and a mycotoxin mitigation additive on growth performance, carcass characteristics, and pork fat quality of growing-finishing pigs.

Two experiments investigated the effects of feeding diets containing 30% of novel high-protein distillers dried grains (HP-DDG) sources to growing–finishing pigs on growth performance, carcass characteristics, and pork fat quality. A four-phase feeding program was used in both experiments, and diets within phases were formulated based on National Research Council (NRC; 2012) recommendations for metabolizable energy and standardized ileal digestible amino acid content of HP-DDG. In Exp. 1, a total of 144 pigs (body weight [BW] = 20.3 ± 1.6 kg) were fed either corn-soybean meal control diets (CON) or 30% HP-DDG diets (HP-DDG) containing 0.7 mg/kg deoxynivalenol (DON), 0.1 mg/kg fumonisins (FUM), and 56 μg/kg zearalenone (ZEA) for 8 wk. On week 9, a mycotoxin mitigation additive (MA) was added to CON and HP-DDG diets, resulting in a 2 × 2 factorial arrangement of treatments consisting of: CON, CON + MA, HP-DDG, and HP-DDG + MA. Pigs fed HP-DDG had lower (P < 0.01) average daily gain (ADG) and average daily feed intake (ADFI) compared with those fed CON during the first 8 wk. After MA was added to diets, pigs fed HP-DDG diets without MA had lower (P < 0.05) overall ADG than those fed HP-DDG + MA and less (P < 0.05) final BW than pigs fed CON or CON + MA. Adding MA to HP-DDG diets containing relatively low concentrations of mycotoxins was effective in restoring growth performance comparable to feeding CON. In Exp. 2, a different source of HP-DDG was used, and mycotoxin MAs were added to all diets at the beginning of the trial. A total of 144 pigs (BW = 22.7 ± 2.3 kg) were fed either a corn-soybean meal control diet or a 30% HP-DDG diet containing 0.5 mg/kg DON and 0.8 mg/kg FUM for 16 wk. Pigs fed HP-DDG diets had less (P < 0.01) final BW and ADG than pigs fed CON, but there were no differences in ADFI. Feeding the HP-DDG diets reduced (P < 0.01) hot carcass weight, carcass yield, longissimus muscle area (LMA), and percentage of carcass fat-free lean compared with pigs fed CON but did not affect backfat (BF) depth. Pigs fed HP-DDG had less (P < 0.01) saturated fatty acid (SFA) and monounsaturated fatty acid (MUFA) content and greater (P < 0.01) polyunsaturated fatty acid (PUFA) and iodine value in BF than pigs fed CON. These results suggest that feeding diets containing relatively low concentrations of co-occurring mycotoxins can be detrimental to growth performance, and the addition of MA alleviated the growth reduction. Feeding 30% HP-DDG reduced BW, ADG, carcass yield, LMA, and percentage of fat-free lean of growing–finishing pigs but yielded acceptable pork fat quality.

Standardized ileal digestible amino acid and metabolizable energy content of wheat from different origins and the effect of exogenous xylanase on their determination in broilers

This study was conducted to determine the standardized ileal digestible amino acids (SID AA) and nitrogen-corrected apparent metabolizable energy (AMEn) contents of 6 wheats from different origins in China and incidentally to investigate the effects of exogenous xylanase addition on SID AA and AMEn determination in broiler chicks. A total of 480 chicks were divided into 48 cages of 10 birds each balanced for body weight and fed 8 types of diets in a completely randomized design (6 replicated cages per diet) from 21 to 26 d of age. The individual wheat constituted the only source of crude protein in a semi-purified experimental diet. A nitrogen-free diet was designed to estimate basal endogenous AA loss and determine the SID AA. Titanium oxide (0.3%) was used as an indigestibility marker, and nutrient digestibility and retention were determined by the substitution method. From day 24 to 26, excreta samples were collected for AMEn determination. On day 26, the birds were euthanized, and ileum contents were obtained for AA digestibility determination. Wheat from Gansu had greater (P < 0.05) SID AA contents except Lys, Thr, Phe, and Cys, with a higher (P < 0.001) AMEn (11.83 MJ/kg) than the other wheats. The SID content of mean indispensable amino acids and dispensable amino acids were 87.35% and 88.17%, respectively, and the average AMEn value of 6 wheats was 11.14 MJ/kg. Compared with the diet without xylanase, the added xylanase resulted in higher (P < 0.05) SID contents of Met, Lys, Trp, Arg, Ile, Leu, Val, Gly, Asp, Glu, Pro, and Ala; the SID AA values were raised by 1.96% (mean of all AA); and the AMEn content was significantly increased (+0.87 MJ/kg) (P < 0.05). In conclusion, origins of wheats have significant effects on SID AA and AMEn values which were positively correlated with crude protein content of wheat; exogenous xylanase addition to a wheat-based poultry diet could significantly improve SID AA and AMEn contents for broilers.

Influence of inclusion level of barley in wheat-based diets and supplementation of carbohydrase on growth performance, nutrient utilisation and gut morphometry in broiler starters

ABSTRACT1. The influence of barley inclusion level and supplementation of a multi-component non-starch polysaccharide degrading enzyme on performance and nutrient utilisation in broilers was investigated. Normal-starch hulled barley was evaluated with five levels of inclusion (0, 141, 283, 424 and 565 g/kg) in a wheat-based diet and two levels of enzyme supplementation (0 and 150 g/tonne of feed; a 5 × 2 factorial arrangement of 10 dietary treatments). All diets were equivalent in metabolisable energy and digestible amino acid contents. A total of 400, one-d old male broilers (five cages/treatment; eight birds/cage) were used in the experiment.2. Regardless of enzyme supplementation, weight gain (WG) increased up to 283 g/kg of barley and was reduced afterwards (P < 0.01). Increasing levels of barley resulted in greater (P < 0.001) gain per feed (G/F). Enzyme addition increased WG (P < 0.05) and G/F (P < 0.001) at each barley inclusion level.3. Birds fed diets with 0 and 565 g/kg barley showed the lowest and highest (P < 0.001to 0.05) digestibility for all nutrients measured, respectively. Digestibility of all nutrients was improved by enzyme supplementation at each barley inclusion level (P < 0.05). The nitrogen-corrected apparent metabolisable energy improved with increasing inclusion of barley (P < 0.001) and supplemental enzyme (P < 0.01). Increasing inclusion of barley increased the relative weight of gizzard (P < 0.001) and reduced jejunal digesta viscosity (P < 0.001). Supplemental enzyme (P < 0.001) reduced digesta viscosity.4. The optimum inclusion level of barley, with respect to growth performance, was 283 g/kg of diet. Increasing barley inclusion improved nutrient and energy utilisation, possibly through lowered digesta viscosity and better function of the gizzard. Feed efficiency and nutrient and energy utilisation can benefit from carbohydrase supplementation in barley-based diets, regardless of barley inclusion level.

Amino acid composition and digestible amino acid content in animal protein by-product meals fed to growing pigs1.

An industry survey and animal experiment were conducted to evaluate the amino acid (AA) compositional variability and standardized ileal digestibility (SID) of AA in animal protein by-products fed to growing pigs. Animal protein by-product meals (212) were categorized into 8 groupings (blood meal, chicken by-product meal, chicken meal, feather meal, meat and bone meal, meat meal, poultry by-product meal, and poultry meal) and analyzed for total AA. Amino acid analysis among (e.g., Lys in blood meal averaged 9.20% compared with 2.31% for feather meal, DM basis) and within (e.g., Lys range of 1.54% in blood meal and 1.44% in feather meal, DM basis) the by-product classifications varied as expected, but on average the total AA values were similar to that reported in the literature. For the determination of the SID of AA, 15 barrows (average initial and final BW of 31.6 and 78.7 kg, respectively) were fitted with a T-cannula in the distal ileum and allotted to 15 diets over nine 7-d periods, resulting in 9 replications per diet. Pigs were fed a basal diet based on soybean meal and dehulled-degermed corn, 13 diets containing 17.5% animal protein by-product meal to partially replace a portion of the soybean meal and dehulled-degermed corn in the basal diet, or a N-free diet. Pigs were re-allotted to diets based on minimizing the number to times that the N-free diet would precede or follow feeding either of the blood or feather meal diets because of concern with inadequate diet consumption, as well as to prevent diets from being re-fed to the same pig during the next or subsequent periods. Values for the apparent ileal AA digestibility of each diet were determined, adjusted to SID based upon the endogenous AA losses determined by feeding the N-free diet, and the SID of AA in each animal protein by-product meal calculated using the difference procedure. The SID of AA varied among (e.g., SID of Lys averaged 91% in chicken meal but 47% in feather meal) and within (e.g., SID of Lys in three meat and bone meals was 80%, 71%, and 54%) the animal protein by-product meals, as would be expected and are consistent with variation reported in the literature. Overall, the data provide total AA composition for 212 samples and SID of AA for 13 samples of animal protein by-product meals, including data on their variability, which is critical for their use in feed formulation programs.

Exploring nutritive profile, metabolizable energy, protein, and digestible amino acids contents of indigenous protein sources of different locations for male broilers

2 experiments were conducted to explore nutrient composition, AME, AMEn, standardized ileal digestibility (SID) of CP, and amino acids (AA) of 4 indigenous protein sources including canola meal (CM), rapeseed meal (RSM), guar meal (GM), and sunflower meal (SFM) collected from 2 different locations, Multan (MUL; n=3) and Sukkur (SKR; n=3), of Pakistan. Higher (P< 0.05) dry matter (DM), CP, and gross energy (GE), whereas lower (P< 0.05) ash contents were found in SKR, CM, and RSM compared with those from MUL. The MUL GM had higher (P< 0.05) crude fiber (CF) and CP, whereas lower (P<0.05) GE compared with those from SKR. The SFM from MUL had higher DM, whereas lower CF and CP contents than SKR. In the first experiment, 216 21-d-old male broilers (Ross 308) were distributed over 8 test diets (4 ingredients×2 locations) and 1 basal diet, with 4 replicates containing 6 birds each (9×4×6), in a complete randomized design to determine AME and AMEn. The results indicated higher (P< 0.05) AME and AMEn in MUL CM than SKR. In the second experiment, 216 21-d-old male broilers (Ross 308) were raised in 36 cages (6 birds each) to determine SID of CP and AA in a complete randomized design. 8 test diets (4 ingredients×2 locations) and a protein-free diet, with 4 replicates each, were tested. The SID of CP and some AA were higher (P< 0.05) in MUL CM and RSM than SKR. The SKR GM had a higher (P< 0.05) SID of CP, arginine, methionine, threonine, valine, and cysteine compared with that from MUL. The SFM from MUL had higher (P< 0.05) SID of CP, arginine, histidine, methionine, valine, alanine, aspartate, cysteine, and serine than SKR. In conclusion, major differences do exist between CM, GM, RSM, and SFM from different locations in terms of nutrients, AME, digestible CP, and AA contents for male broilers.

Energy values and standardized ileal digestibility of amino acids in some feedstuffs for broilers

The objective of this study was to determine the energy values, standardized ileal digestibility coefficients and digestible amino acid contents of parboiled brown rice bran (PBRB), protein sorghum meal (PSM) and bread waste meal (BWM) in broiler diets. In the first trial, 144 broiler chicks at 14 days of age were evaluated in a completely randomized design involving three feedstuffs + a control diet, with six replicates and six birds per experimental unit. The total excreta collection method was adopted to determine the energy values of the feedstuffs. In the second trial, 144 broilers at 24 days of age were used in a completely randomized design involving three feedstuffs + a protein-free diet, with six replicates and six birds per experimental unit. Ileal digesta was harvested to determine the standardized ileal digestibility coefficients and digestible amino acid contents of the feedstuffs. The nitrogen-corrected apparent metabolizable energy (AMEn) values of PBRB, PSM and BWM were 2638, 2799 and 3399 kcal.kg-1, respectively. The metabolizability coefficients of AMEn (CAMEn) of PBRB, PSM and BWM were 54.13, 57.35 and 86.66%, respectively. Bread waste meal had the highest CAMEn (p &lt; 0.05) and standardized ileal digestibility of amino acids (p &lt; 0.01), followed by PBRB and PSM. The main limiting digestible amino acids in PBRB, PSM and BWM were found at the following respective levels: methionine - 0.19, 0.33 and 0.24%; lysine - 0.40, 0.46 and 0.40%; threonine - 0.25, 0.50 and 0.45%; and valine - 0.44, 0.73 and 0.48%.

Accurate prediction of nutritional value of sorghum grain using image analysis

ABSTRACT1. This study evaluated the application of L (lightness)*a (redness) and *b (blueness) colour analysis and chemical compositions to predict the nutritional value of sorghum grain.2. A total of 12 varieties of sorghum grain were analysed for L*a*b colours, chemical composition, energy and total and digestible amino acid content. Regression models based on the linear, non-linear and the interaction effects of inputs were applied to predict the nutritional value of sorghum grains either using L*a*b colour or chemical composition, as the model inputs.3. The results illustrated a significant relationship between a*b and/or chemical compositions with energy content in the samples of sorghum grain. The provided estimation equations presented high goodness of fit in terms of R2adj ranging from 0.744 to 0.999.4. Total and digestible amino acids of sorghum grain were estimated based on a*b and chemical compositions data with the goodness of fit ranging from 0.641 to 0.999 (R2adj).5. In conclusion, the L*a*b colour analysis may be used for developing equations to predict nutritional value of sorghum grain as an alternative approach to the conventional time-consuming and costly chemical and bioassay methods.