Apparent Metabolizable Energy Research Articles

Effects of Feeding Low Protein Diets with Different Energy-to-Protein Ratios on Performance, Carcass Characteristics, and Nitrogen Excretion of Broilers.

This study shows the effects of feeding low protein (LP) diets with different energy-to-protein ratios were evaluated on the production parameters, carcass composition, meat quality, nitrogen retention, and excreta composition of broilers. A total of 576-day-old Ross 308 broilers were fed a control diet (C) and three LP diets containing 1.5% less crude protein than diet C for 41 days. The LP1 treatment was isocaloric with diet C, while the dietary apparent metabolizable energy corrected by nitrogen (AMEn) levels in the case of the LP2 and LP3 treatments were reduced by 1.5% and 3%, respectively. The LP diets were supplemented with six crystalline essential amino acids (AA) to meet the standardized ileal digestible AA requirements of broilers. The LP1 treatment did not affect the performance parameters of broilers and increased the breast meat yield, the nitrogen retention and decreased drip loss of breast meat and the total-N and uric acid-N nitrogen excretion of birds in comparison with the C group. Although the energy-reduced LP2 and LP3 diets resulted in lower final body weight, they did not affect the carcass composition, breast meat quality, nitrogen retention, and excreta composition of birds compared with the control treatment.

Meta-analysis of the effect of black soldier fly larvae meal in diet on broiler performance and prediction of its metabolisable energy value

The aims of the present work were to determine by meta-analysis the responses of broiler performance to increasing dietary levels of black soldier fly larvae meal (BSFLM) and to develop prediction models of the apparent metabolisable energy corrected to zero nitrogen balance (AMEn) of BSFLM. Eighteen studies from 12 countries that sum up to 20 experiments and involved a total of 63 treatments with 468 replicates and 4229 birds fulfilled the requirements for the meta-analysis. Four papers from three countries that investigated eight different samples of BSFLM were selected for development of AMEn prediction by means of regression analysis or artificial neural network (ANN) modelling. Growth performance results were not affected (p > .05) by the presence of BSFLM at levels of 5.7 ± 2.3 and 15.5 ± 6.0% in the diet. Multiple linear regression and ANN models showed high precision and accuracy, were unbiased and performed almost identically in the evaluation dataset (R2 = 0.856 and 0.858 and root mean square error of prediction as percentage of the observed mean = 5.216 and 5.241%). Feeding broilers with diets containing 15% BSFLM is not expected to have negative effects on growth performance. The following regression model could be useful for the estimation of AMEn in BSFLM: AMEn = 4.08 (± 0.330) + 0.295 (± 0.0158) × GE + 0.186 (± 0.0021) × EE; where AMEn and gross energy (GE) are MJ/kg dry matter and crude fat (EE) is % dry matter.

The Effects of Using Clove Meal (Syzygium aromaticum L.) as Feed Additive on Nutrient Digestibility and Metabolizable Energy of Broiler Chicken

This study was aimed at determining the effect of clove meal addition in diets on nutrient digestibility and metabolizable energy in broilers and whether it could be an alternative to antibiotics or not. In this experiment, twenty-four 35-day-old broilers of the chicken strain Lohman were used. A total of twenty broiler chickens were selected as representatives for determining the digestibility. The treatment diets were: T0 (basal diet), T1 (basal diet + 0.25% clove meal), T2 (basal diet + 0.5% clove meal), T3 (basal diet + 0.75% clove meal), and T4 (basal diet + 1% clove meal). The variables measured were dry matter digestibility, organic matter digestibility, apparent protein digestibility, true digestible protein (TDP),Apparent Metabolizable Energy (AME), True Metabolizable Energy (TME), Nitrogen Corrected Apparent Metabolizable Energy (AMEn) and Nitrogen Corrected True Metabolizable Energy (TMEn). A completely random design was used, with five treatments and four replications. The data were analyzed using analysis of variance (ANOVA), and differences among treatments were examined using Duncan’s multiple range test. The results show that the treatment influences significantly (P<0.05) of dry matter, organic matter, apparent protein digestibility, and TDP. In contrast, there wereno significant effects (p>0,05) of dietary treatment on AME, TME, AMEn, and TMEn. However, the addition of 0.75% clove meal indicated the best result in AME, TME, AMEn, and TMEn. It can be concluded that the experiment indicated that the addition of clovemeal (Syzygium aromaticum L.) in 0.75% on the diet of broiler chickens was effective in increasing the digestibility of dry matter, organic matter,crude protein, TDP, and metabolizable energy.

Effects of Solid-State Fermentation on the Standardized Ileal Digestibility of Amino Acids and Apparent Metabolizable Energy in Peanut Meal Fed to Broiler Chickens

Peanut meal (PNM) is a byproduct of the peanut oil extraction process, but its application is seriously limited by the presence of anti-nutritional factors, imbalance in amino acid profiles, and susceptibility to mycotoxin contamination. This study was conducted to investigate the effects of solid-state fermentation on the nutritional quality of PNM, as well as the effects of PNM and fermented peanut meal (FPNM) on the ileal digestibility of amino acids and apparent metabolizable energy (AME) of broiler chickens. The results indicated that the fermentation improved the quality of PNM by increasing the crude protein, TCA-soluble protein, and L-lactic acid concentration (p < 0.05), and decreasing the crude fiber, phytic acid, and aflatoxin B1 concentration (p < 0.05). Solid-state fermentation also increased the free amino acids level and improved the balance of hydrolyzed amino acids of PNM. A nitrogen-free diet was used to determine the loss of endogenous amino acid in birds, and the PNM or FPNM as the only protein source to formulate semi-purified diets. The result showed that feeding on FPNM resulted in higher apparent ileal digestibility (AID) and standardized ileal digestibility (SID) values of the essential amino acids of methionine, lysine, leucine, and phenylalanine (p < 0.05). Moreover, the AID and SID values of the non-essential amino acids of FPNM were both higher than those of PNM, except for proline (p < 0.05). The AME was determined by the classic substitution method, and the results showed that fermentation had no effect on the AME value (p > 0.05). In conclusion, solid-state fermentation improved the nutritional value of PNM, and FPNM was a potential ingredient as an alternative protein source for broilers.

Effects of bee pollen inclusion on performance and carcass characteristics of broiler chickens

This study was conducted to determine the effect of bee pollen (BP) inclusion on performance and carcass characteristics in broiler chickens. A total of 240 Ross 308 broiler chicks were allocated to 4 treatments (BP inclusion levels of 0, 4, 8, or 12 g/kg DM feed) in a randomized complete block design with sex as a block having 3 replicates with 10 chickens per replicate. After 21 d, the chickens remained in their treatment groups and fed standard grower diet. The results of the current study revealed that BP inclusion had positively improved (P < 0.05) average weekly feed intake (FI), body weight (BW), body weight gain (BWG), and feed conversion ratio (FCR) in both sexes. However, the apparent nutrient digestibility, metabolizable energy (ME), and nutrient digestibility were not affected by the dietary BP. Furthermore, carcass yield in both sexes was improved (P < 0.05) by BP inclusion levels. In contrast, meat pH, shear force, and sensory evaluation in both sexes were not affected (P > 0.05). The results suggest that the broiler chicks can utilize bioactive compounds in BP when supplemented in the starter diets and subsequently improve their growth parameters throughout the growing period as well as carcass yield at slaughter age. These positive improvements could be due to high quality amino acids, essential oils, vitamins, and minerals of BP. Therefore, it is concluded that BP inclusion level of 12 g/kg or more in the starter diets could have positive effects on growth performance and carcass yield at slaughter age without causing adverse effects on meat physico-chemical properties and sensory evaluation in both male and female broiler chickens.

Non-Starch Polysaccharide-Degrading Enzymes Increase the Performance of Broiler Chickens Fed Wheat of Low Apparent Metabolizable Energy

The effect of a commercial glycanase product (Avizyme TX) on the performance of 4-wk-old broiler chickens fed wheats with low and normal apparent metabolizable energy values was studied. Controls were fed a corn-based diet. Supplementation with the enzyme product significantly (P < 0.01) increased the apparent metabolizable energy of the low metabolizable energy wheat from 12.02 to 14.94 MJ/kg dry matter. The apparent metabolizable energy value of the normal wheat was increased from 14.52 to 14.83 MJ/kg dry matter; this was, however, not significant. Birds fed the low metabolizable energy wheat diet had significantly (P < 0.01) higher digesta viscosity and lower small intestinal starch and protein digestibilities than birds fed the normal wheat diet. Chickens fed the low metabolizable energy wheat tended to grow less than those fed the normal wheat diet. When the low metabolizable energy wheat + enzyme diet was fed, digesta viscosity was significantly (P < 0.01) lower (20.28 vs. 10.36 mPa·s), and small intestinal digestibility coefficient of starch was significantly (P < 0.01) greater (0.584 vs. 0.861) relative to values in birds fed the low metabolizable energy wheat diet alone. Although the protein digestibility coefficient also increased from 0.689 to 0.745, the difference was not significant. Weight gain and feed efficiency of birds fed the low metabolizable energy wheat + enzyme equaled those of controls. The enzyme product significantly (P < 0.01) increased the solubilization of non-starch polysaccharides within the gastrointestinal tract of birds fed both types of wheat diets. This experiment demonstrated that non-starch polysaccharide-degrading enzymes markedly increase the nutritive value of low metabolizable energy wheat broiler chicken diets, suggesting that increased level of viscous non-starch polysaccharides may cause the low apparent metabolizable energy contents of some wheats.

Comparative study of apparent metabolizable energy and net energy values of dephenolized cottonseed proteins for laying hens

Optimizing the energy utilization of nutrients and ensuring maximum benefits are continuous goals for livestock producers. The net energy (NE) value of feed reflects its nutritional value in the precision feeding system. An experiment was conducted to determine the apparent metabolizable energy (AME) and NE values of 3 types of dephenolized cottonseed protein (DCP) for Hy Line Brown hens aged 42 to 45 weeks using the reference diet substitution method. A reference diet based on corn soybean meal was used to meet the nutritional needs of Hy Line Brown laying hens. To render the crude protein and energy values of the 3 test diets similar, 10.5%, 12%, and 16% of the gross energy yielding ingredients from the reference diet were replaced with DCP 1, DCP 2, and DCP 3, respectively. The birds were fed 4 diets during a 7-d adaptation period. After the dietary adaptation period, 2 birds per replicate from each treatment group were placed in an individual open circuit respiratory calorimetry chamber for a 3-d experimental period. Daily O2 consumption and CO2 production were recorded, and excreta samples were collected. The AME values of DCP 1, DCP 2, and DCP 3 were 3,049.05, 2,820.13, and 2,982.31kcal/kg of dry matter (DM), respectively. The NE values of DCP 1, DCP 2, DCP 3 were 1,475.77, 1,910.31, and 1,905.37kcal/kg of DM, respectively, and the NE:AME ratios were 48.40%, 67.74%, and 63.89%, respectively. Our data show that the AME value of DCP does not reflect the nutritional value of the feed. The NE value of DCP with a high ME value was not necessarily high.

Diferentes níveis de fitase e de densidades energéticas em dietas de frangos de corte sobre desempenho, digestibilidade de nutrientes e integridade óssea de 28 a 35 dias de idade

ABSTRACT The study was carried out with the objective of evaluating the effects of using phytase levels at different energy densities in the diet of broilers, from 28 to 35 days of age. The experimental diets contained increasing levels of apparent metabolizable energy corrected for nitrogen balance and different levels of phytase. Growth performance variables, nutrient digestibility, as well as variables related to bone integrity were examined. Diets containing 500 FTU/kg in combination with 3150kcal.kg-1 of AMEn resulted in better growth performance. Supplementation with 500 and 1000 FTU/kg in the diets provide better coefficients of apparent and ileal digestibility of calcium and phosphorus, but negatively influence the deposition of calcium, phosphorus, dry matter, and ash in the tibia, in addition to adversely affecting the breakage and area of these bones in broilers. Bone length and the levels of magnesium and zinc present in the tibias were not influenced by the energy and phytase levels of the diets. There is no interaction between the different energetic densities and the phytase doses in the variables analyzed in the studied period. Increasing the energy density of diets resulted in improved apparent and ileal digestibility for most nutrients.

The apparent metabolisable energy and ileal amino digestibility of black soldier fly (Hermetia illucens) larvae meal for broiler chickens

ABSTRACT 1. Two experiments were conducted to determine the apparent metabolisable energy (AME) and standardised amino acid digestibility coefficients (SIDC) of black soldier fly larvae (BSFL) for broiler chickens. 2. The BSFL contained, on a g/kg dry matter basis: crude protein, 486; crude fat, 320; ash, 58.5; neutral detergent fibre, 181; calcium, 6.8 and phosphorus, 9.1. 3. In Experiment 1, an AME assay was performed wherein broilers were fed two experimental diets (a maize-soy basal diet and a test diet containing 250 g/kg BSFL) for 4 d from d 18 posthatch. The AME of BSFL was calculated based on the difference between the AME values of basal and test diets. The AME and nitrogen-corrected AME were determined to be 19.1and 18.0 MJ/kg of dry matter, respectively. 4. In Experiment 2, the ileal amino acid (AA) digestibility of BSFL was determined using 22-d-old broilers by the direct method and the digesta was collected on d 25. The ratios between the AA and titanium in the diet and digesta were used to calculate the apparent digestibility and then standardised using previously published endogenous losses to estimate the SIDC of AA. The SIDC of Lys, Met, Thr, Val and average SIDC of AA in our BSFL sample were 0.85, 0.90, 0.91, 0.87 and 0.84, respectively. 5. The findings showed that the BSFL meal is a good source of available energy and digestible AA, and could be a potential substitute for soybean meal in broiler diets.

Determination of prediction equations for apparent metabolizable energy corrected for nitrogen of corn gluten meal and canola meal in broilers

The objectives of this experiment were to determine the AMEn content of different samples of corn gluten meal (CGM) and canola meal (CM) by a reference diet method and to develop prediction equations based on the chemical composition to estimate the AMEn value of CGM and CM in broilers. A total of 300 one-day-old male broiler chicks were randomly assigned to fifteen treatments (14 experimental diet and 1 reference diet) with 4 replicates of each with 5 birds per replicate. At first, birds were fed a starter diet from 0 to 10 d of age, and then, a grower diet from 11 to 23 d of age. To determine the AMEn content, the test diet consisted of 60% reference diet, 38% each test CGM or CM, and 2% minor ingredients. To adaptation, the broilers were fed experimental diets for 4 d, and then feces were collected on 28 d. The gross energy values and chemical compositions among the CGM and CM from different origins were significantly different. The AMEn values of the CGM samples varied from 3,123 to 3,918 kcal/kg, and for the CM, the range was from 1,578 to 2,109 kcal/kg. At the end of the experiment, data were analyzed with SPSS software, and a regression equation was obtained based on the chemical composition. The best equations were selected based on the standard of prediction and regression adjusted R2. The equation, AMEn=49.196×CP+80.87×EE (SEP 180.99; adjusted R2 0.97), was selected to predict the AMEn value of CGM, and the equation, AMEn=631.55×EE+16.716×CP (SEP 55.3; adjusted R2 0.94), was selected to predict the AMEn value of CM.

The effect of amylase supplementation on individual variation, growth performance, and starch digestibility in broiler chickens

The objective of this study was to evaluate the variance of starch digestibility in broilers individually fed diets without or with supplemental exogenous amylase. A total of 120 d-of-hatch male chicks were individually reared from 5 to 42 d in metallic cages and fed maize-based basal diets or diets containing 80 kilo-novo-α-amylase units/kg (60 birds or replicates per treatment). Beginning on d 7, feed intake, body weight gain, and feed conversion ratio were recorded; partial excreta collection was conducted every Monday, Wednesday, and Friday until 42 d, when all birds were sacrificed for individual collection of duodenal and ileal digesta. Lower feed intake (4,675 vs. 4,815 g) and feed conversion ratio (1.470 vs. 1.508) were observed in amylase-fed broilers during the overall period (7-43 d; P < 0.01), whereas body weight gain was not affected. Amylase supplementation improved total tract starch (TTS) digestibility (P < 0.05) on each day of excreta collection (except for d 28, where no difference was found), averaging 0.982 vs. 0.973 compared to basal-fed broilers from d 7 to 42. Both apparent ileal starch (AIS) digestibility and apparent metabolizable energy (AMEN) were increased (P <0.05) from 0.968 to 0.976 and from 3,119 to 3,198 kcal/kg, respectively, with enzyme supplementation. Activity of amylase in the duodenum was higher (18.6 vs. 50.1 IU/g of digesta) in supplemented birds. Amylase supplementation led to a reduced coefficient of variation for both TTS (averaged 2.41 vs. 0.92% from 7 to 42 d) and AIS digestibilities (1.96 vs. 1.03%), as well as AMEN (0.49 vs. 0.35%), when compared to the nonsupplemented group, indicating lower individual heterogenity. An age effect was detected for TTS digestibility, as both groups saw an increase during the first weeks (slightly more pronounced in the supplemented group); older birds (d 30 onwards) presented a lower TTS digestibility compared to ages between 7 and 25 d. In conclusion, amylase supplementation in maize diets for broilers can attenuate individual bird variation for starch and energy utilization by increasing amylase activity and enhancing starch digestibility.

Effect of Irrigation, Nitrogen Fertilization and Amino Acid Biostimulant on Proximate Composition and Energy Value of Pisum sativum L. Seeds

The study investigated the impact of biological and agricultural conditions on the chemical composition and energy value of pea seeds for poultry feed. In the experiment, the species assessed was pea (Pisum sativum L.), a determinate form, cultivar (cv.) Cysterski. During the field experiment, the response of peas to the following experimental factors was assessed: first factor—irrigation (yes, no), second factor—nitrogen fertilization (0, 20 and 40 kg N·ha−1), third factor—amino acid biostimulant (yes, no). In both years of experiments, representative seed samples were collected, in which the chemical composition was assessed for the content of dry matter, crude protein, crude fat, crude fiber, and nitrogen free extract. Additionally, in order to assess the suitability of the evaluated pea seeds as poultry feed, the energy value expressed in the form of apparent metabolizable energy (AMEn) was estimated. The protein content in pea seeds increased after the application of the biostimulant, both with and without irrigation. Statistically significant differences in the crude fiber content in pea seeds were found under the influence of the interaction of irrigation and nitrogen fertilization. The use of the biostimulant significantly increased the energy value of pea seeds.

Supplementation of amylase or amylase + xylanase improves performance and metabolism of broilers fed with diets containing newly harvested maize

How supplementation with amylase or amylase + xylanase in newly harvested maize-based diets affects broiler nutrient metabolism and performance is unclear. Thus, this study evaluated whether the supplementation of amylase (CN) or amylase + xylanase (CAX) improves performance and metabolism of broilers fed with newly harvested maize-based diets during a 6-week production. The results showed that the body weight gain of broilers fed with CA or CAX diet was higher than that with the control (CN) diet at 1–21 d of age; however, an opposite trend was observed for feed/gain (p < 0.05). Furthermore, 150, 64 and 35 different metabolites were found between CA/CN, CAX/CN and CAX/CA, respectively. Overall, amylase supplementation improved broiler growth performance at 1–21 d of age, and the positive effects of amylase on nutrient utilization were mostly related to nicotinate, retinol and glutathione metabolism improvement. Moreover, CAX diet increased apparent metabolizable energy and growth performance of broilers at 22–42 d of age, and the difference might be related to sphingolipid, porphyrin and chlorophyll metabolism regulation. The findings prove amylase + xylanase supplementation is an effective method to improve the nutritional value of newly harvested maize for broilers.

Broiler Age Influences the Apparent Metabolizable Energy of Soybean Meal and Canola Meal.

The effects of broiler age on the apparent metabolizable energy (AME) and nitrogen-corrected AME (AMEn) of soybean meal (SBM) and canola meal (CM) were examined. A corn-SBM basal diet was developed, and two test diets were formulated by substituting (w/w) 300 g/kg of the basal diet with SBM or CM. Six groups of broiler chickens, aged 1-7, 8-14, 15-21, 22-28, 29-35 or 36-42 d post-hatch, were utilized. Each diet, in pellet form, was randomly allocated to six replicate cages in each age group. Except for the 1-7 d age group, the birds were fed a starter (d 1-21) and/or a finisher (d 22-35) diet prior to the introduction of the experimental diets. The number of birds per cage was 10 (d 1-7), 8 (d 8-14) and 6 (d 15-42). The AME and AMEn of SBM and CM were determined by total excreta collection. The data for each protein source were subjected to orthogonal polynomial contrasts using the General Linear Models procedure. Bird age decreased the retention of dry matter quadratically (p &lt; 0.001) for both SBM and CM. The retention of nitrogen decreased linearly (p &lt; 0.001) with the advancing age of broilers for SBM and CM. The AMEn of SBM and CM decreased quadratically (p &lt; 0.001) as the birds grew older. The highest AMEn was observed during week 1 for both SBM and CM, then declined until week 3, followed by increases thereafter. The current results showed that the age of broiler chickens influenced the AMEn of SBM and CM and supported the use of age-dependent AMEn of feed ingredients in diet formulations.

Effect of exogenous emulsifier and different fat sources on the performance, carcass characteristics, nutrient digestibility, and serum lipid profile of broiler chickens

A study was conducted to evaluate the effect of an emulsifier on reduced-energy diets using two fat sources for broilers. The study was designed as a 2 x 3 factorial arrangement of treatments. The first factor was 2 fat sources (poultry fat or beef tallow). The second factor was a basal diet with the recommended energy levels, a diet with a 0.83 MJ/kg of energy reduction, and a diet with an energy reduction and inclusion of 1 g emulsifier/kg of diet. The emulsifier used in this study was composed of soy lecithin and polyethylene glycol ricinoleate. The emulsifier increased apparent metabolizable energy (AME) and apparent metabolizable energy corrected for nitrogen balance (AMEn) in beef tallow diets compared to energy-reduced diets (P&lt;0.001). Broilers fed poultry fat had higher weights and weight gains at 35 and 42 d of age (p=0.001), and they had higher daily deposition of fat in the carcass (P = 0.025) when compared to diets with beef tallow. The inclusion of emulsifiers in broiler diets improves AME and AMEn but did not affect the energy reduction diets, whichresulted in reduced performance, decreasing daily fat deposition, but without effects on serum lipid profile in broilers.

Nutrient digestibility in broiler chickens fed diets containing high levels of soybean oil is affected by the source of fiber

This study evaluated the effects of including soluble and insoluble dietary fiber sources in soybean oil-containing diet for broiler chickens on coefficient of apparent ileal digestibility (AID) of amino acids, coefficient of apparent retention (AR) of nutrients, and nitrogen-corrected apparent metabolizable energy (AMEn). A total of 180 broilers were divided into 30 groups and fed 3 diets from day 14 to 21 of age. The diets were corn–soybean meal containing 6.8% soybean oil without or with soybean hulls (SBH) or sugar beet pulp (SBP) at 8.0% as sources of insoluble and soluble fiber, respectively. The SBH and SBP contained 6.0% and 14.7% of soluble dietary fiber and 60.5% and 37.0% of insoluble dietary fiber, respectively. The AID of indispensable amino acids was decreased ( P &lt; 0.05) due to dietary inclusion of SBH, but not of SBP. Dietary SBH and SBP reduced the AR of gross energy (by 14% and 8%, respectively) and AMEn (by 20% and 14%, respectively). Overall, inclusion of SBH or SBP at 8.0% in a corn–soybean meal-based diet for broilers that contains high level of soybean oil might not improve nutrient digestibility. However, SBP has less detrimental effects on nutrient digestibility than SBH.

Predicting the metabolizable energy and metabolizability of gross energy of conventional feedstuffs for Muscovy duck using in vitro digestion method.

In total, two experiments were conducted to evaluate the effectiveness of an in vitro digestion method for predicting the metabolizable energy (ME) and metabolizability of gross energy (ME/GE) values using in vitro digestible energy (IVDE) and the digestibility of gross energy (IVDE/GE) content, respectively, of conventional feedstuffs for Muscovy ducks. In experiment 1, the apparent metabolizable energy (AME), true metabolizable energy (TME), AME/GE, and TME/GE of eight-grain feedstuff samples (two corn samples, three sorghum samples, and three barley samples) and eight protein feedstuff samples (two soybean meal samples, three cottonseed meal samples, and three rapeseed meal samples) were determined by the tube-feeding method with six different ducks for each sample. In experiment 2, a computer-controlled simulated digestion system (CCSDS) contain simulated digestive fluid was used to determine the enzymatic hydrolysis energy value of feedstuffs, which was defined as IVDE in our study. The simulated gastric fluid containing pepsin and simulated small intestinal fluid containing amylase, trypsin, and chymotrypsin for the in vitro gastric and intestinal digestion, respectively. The IVDE and in vitro digestibility of GE (IVDE/GE) of 16 feedstuff samples were determined using the CCSDS with five replicates per sample. The results showed that the IVDE and IVDE/GE were positively correlated with ME and ME/GE of feedstuffs, respectively. The coefficient of determination of eight regression models in predicting ME (grain feedstuffs: AME = 1.050 × IVDE- 0.9293, TME = 1.032 × IVDE + 0.6478; protein feedstuffs: AME = 1.331 × IVDE- 6.685, TME = 1.269 × IVDE-3.490) and ME/GE (grain feedstuffs: AME/GE = 1.069 × IVDE/GE- 6.516, TME/GE = 1.068 × IVDE/GE + 0.7764; protein feedstuffs: AME/GE = 1.093 × IVDE/GE -19.21, TME/GE = 1.196 × IVDE/GE - 13.25) of feedstuffs for Muscovy ducks ranged from 0.8610 to 0.9921. The accuracy of the regression model was acceptable as the difference between measured and predicted ME and ME/GE values was less than 0.45 MJ/kg (100 kcal/kg) and 2.62% for 14 of the 16 feed samples, respectively. In conclusion, the in vitro digestion method can be used to predict the ME and ME/GE of conventional feedstuffs for Muscovy ducks with acceptable accuracy.

Enhancing the nutritive value of canola meal for broiler chickens through enzymatic modifications.

Enzymatic modification of canola meal (CM) is a potential method to enhance its nutritional value as it can depolymerize nonstarch polysaccharides (NSP) and mitigate its potential antinutritive properties. Based on the previous studies, pectinase A (PA), pectinase B (PB), xylanase B (XB), and invertase (Inv) were used for the enzymatic modifications. The highest NSP depolymerization ratio was obtained when 4 g/kg of each PA, PB, and XB, and 0.2 g/kg of Inv were used during 48 h incubation at 40 °C. In the current study, changes in pH, simple sugars, sucrose, oligosaccharides, and NSP contents during the enzymatic modification (CM+E) of CM were measured and compared to Control (CM) without enzymes addition or with the addition of bacteriostat sodium azide (CM+E+NaN3). The results showed that spontaneous fermentation occurred during incubation. After incubation, the pH of the slurry decreased, lactic acid was produced, phytate disappeared, and the concentration of simple sugars decreased substantially. The NSP of the slurry was progressively depolymerized by the enzyme blend. The chemical composition and nutritive value of enzymatically-modified CM (ECM) were evaluated. Ross 308 broilers were randomly assigned to 18 cages of six birds each for the standardized ileal amino acid digestibility (SIAAD) and nitrogen-corrected apparent metabolizable energy (AMEn) assay. A corn/soybean meal-based basal diet formulated to meet Ross 308 breeder recommendations and two test diets contained 70% of the basal diet and 30% of CM or ECM, respectively, were fed to Ross 308 from 13 to 17 d of age. No difference was observed between SIAAD of CM and ECM. The AMEn value of ECM was 2118.0 kcal/kg on a dry matter basis which was 30.9% greater (P < 0.05) than the CM.

Effects of pretreating wheat middlings and sunflower meal with fiber degrading enzymes on components solubilization and utilization in broiler chickens.

Pretreating fibrous feedstuffs with exogenous enzymes may improve their utilization in broiler chickens. Pretreatment of wheat middlings (WM) and sunflower meal (SM) with fiber degrading enzymes (FDE) was investigated for 1) in vitro solubilization of crude protein (CP) and fiber-degrading (experiment 1), and 2) apparent retention (AR) of CP, neutral detergent fiber (NDF), nitrogen corrected apparent metabolizable energy (AMEn), as well as the concentration of ceca digesta metabolites in broiler chickens (experiment 2). In experiment 1, WM was pretreated with FDE and SM with FDE ± protease and incubated in a shaker for 24 or 48 h at 40°C and 200 rpm. Samples were centrifuged, and the supernatant used for assay of sugars and organic acids and pellet processed for determination of apparent disappearance (AD) of dry matter (DM), fiber, and CP solubilization. In experiment 2, WM and SM were pretreated with FDE for 24 h, oven-dried, and incorporated in iso-caloric and iso-nitrogenous experimental diets. Diets were: 1) a corn-soybean meal positive control (PC); 2) PC plus untreated WM and SM (negative control, NC), and diets 3, 4, 5, and 6 test diets, in which the untreated WM and SM in NC were replaced with pretreated WM and SM at 25% (N25), 50% (N50), 75% (N75), and 100% (N100), respectively. Diets were prepared in mash form in two phases (starter, days 0 to 21 and finisher, days 22 to 42) and had TiO2 (0.3%) as an indigestible marker. A total of 288 Ross708 d-old male broiler chicks were placed in cages based on body weights (6 birds/cage) and allocated diets (n = 8). Birds had free access to feed and water. Samples of excreta for AR and AMEn, and of ceca digesta for the concentration of short-chain fatty acids (SCFA) were collected at the end of each phase. Pretreatment with FDE increased (P < 0.001) solubilization of CP, AD of NDF, and release of sugars and organic acids in the supernatant. The mixture of FDE and protease further increased (P < 0.001) CP solubilization in SM. Feeding pretreated WM and SM had a linear response (P ≤ 0.038) on AMEn, and gross energy (GE) (day 21) and a quadratic response (P < 0.05) on AR of components and AMEn (day 42) and concentration of total SCFA on day 42. On day 42, N25 and N50 had higher AR of DM, CP, NDF, and GE than N75 and N100. In conclusion, pretreatment of WM and SM with enzymes increased CP and fiber degradation. Incorporating moderate amounts (N25 and N50) of pretreated WM and SM in a corn-soybean meal diet fed to broiler chickens improved nutrient and energy utilization.

Adição de emulsificante nas rações de frangos de corte com redução dos níveis de energia metabolizável

Abstract This study aimed to evaluate the effect of including soy lecithin emulsifier (SL) in broiler diets with reduced metabolizable energy levels and to correlate it with nutrient metabolizability coefficients, as well as to determine apparent metabolizable energy (AME). Two metabolic trials were conducted in a completely randomized design with a 3x2 factorial arrangement (diet with three levels of metabolizable energy, with or without the inclusion of emulsifier), totaling six treatments. In the starter phase, chicks received diets with 2,950, 3,050, and 3,150 kcal/kg of metabolizable energy, with six replications of 10 birds each, totaling 360 birds. In the grower phase, the energy levels of 3,100, 3,150, and 3,200 kcal/kg of feed were tested in 210 birds were used in seven replications of five chicks each. An interaction effect was observed in the starter phase, with the nitrogen metabolizability coefficient increasing when the emulsifier was added to diets with reduced energy. Additionally, emulsifier inclusion increased nitrogen-corrected AME (AMEn). An interaction effect was also present in the grower phase, with AME and AMEn increasing when the emulsifier was added to diets with lower energy levels. In summary, emulsifier inclusion in broiler diets can reduce metabolizable energy while improving AMEn in both the starter and grower phases, as well as AME in growing broilers.