Apparent Metabolizable Energy Content Research Articles

Effects of Feeding Prosopis juliflora Pods with and Without Exogenous Enzyme on Performance, Meat Quality and Health of Broiler Chickens

Two experiments were conducted to evaluate the use of Prosopis juliflora pods as a partial replacement of corn as a source of energy for growing broiler chicken. The main objective of Experiment 1, an ileal digestibility assay, was to assess the nutritional value of Prosopis juliflora pods compared with corn for feeding broiler chicken. The two test ingredients, Prosopis juliflora pods and corn were given alone to determine apparent metabolizable energy (AME) and apparent ileal digestibility of crude fibre. Prosopis juliflora pods had significantly lower AME content (10.64 vs 15.26 MJ/kg) and lower apparent ileal digestibility coefficient for crude fibre (0.24 vs 0.63) than corn (p<0.001). The objective of Experiment 2, a growth study, was to test the effect of exogenous enzymes on the nutritive value of Prosopis juliflora pods. Three Prosopis juliflora pods contents (5, 10 and 15%) with and without enzyme supplementation were evaluated. Daily feed intake, body weight gain and feed conversion ratio were measured. At the end of Experiment 2, 64 birds were randomly selected and slaughtered to evaluate carcase and meat quality characteristics. Substitution of corn by 10 and 15% Prosopis juliflora pods significantly depressed AME (p<0.001). Enzyme supplementation did not improve crude fibre digestibility. The inclusion of Prosopis juliflora pods in the diets, except at 5 % decreased average daily gains, feed intake and feed conversion ratio (p<0.001). Addition of Prosopis juliflora pods caused a significant increase in the weights of total digestive tract, pancreas and caecum (p<0.01). Addition of Prosopis juliflora pods or the exogenous enzyme had no significant effect on carcase or meat quality characteristics, haematology, serum biochemistry and sensory evaluation. This study indicated that Prosopis juliflora pods can be included at levels of 5% in broiler diets without affecting performance.

Nutrient analysis, apparent metabolisable energy and ileal amino acid digestibility of full fat soybean for broilers

Nutrient composition, ileal amino acid digestibility and apparent metabolisable energy (AME) of four full-fat soybean (FFSB) samples, collected from commercial feed mills in Southeast Asia, were evaluated using laboratory analyses and animal studies. The AME assay was conducted with broilers using the classical total excreta collection between days 21 and 29 posthatch. A maize-soy basal diet was formulated and test diets, each containing different FFSB samples, were developed by replacing (w/w) 300g/kg of the basal diet with FFSB. The AME of FFSB was calculated based on the difference between AME values of the basal and test diets. The ileal amino acid digestibility assay was conducted with 29-day-old broilers using assay diets containing FFSB as the only source of protein. Digesta from lower ileum was collected on day 34. The ratios between the titanium and amino acids in the diet and digesta were used to calculate the digestibility. The crude protein and fat contents of the four FFSB samples ranged from 351 to 399g/kg and from 177 to 192g/kg, respectively. The AME contents varied widely between the four samples, ranging from 12.62 to 15.46MJ/kg. The standardised ileal digestibility coefficient of protein ranged from 0.763 to 0.821. Variations in the digestibility of amino acids and digestible amino acid contents generally followed that observed for protein digestibility. In conclusion, FFSB contained more fat and AME than soybean meal, but less digestible contents of protein and amino acids due to the diluting effect of fat. Overall, these data show that properly processed FFSB is a valuable feedstuff and offers an attractive method of adding fat to poultry diets.

Effect of dietary inclusion level of a multi-species probiotic on broiler performance and two biomarkers of their caecal ecology

The effect of the dietary inclusion level of a three-species probiotic on broiler performance, nutrient digestibility, caecal microbiota composition and volatile fatty acid (VFA) pattern was evaluated. Day-old Cobb broilers (n = 448) were allocated in four treatments for 6 weeks. Each treatment had four replicates (two per gender) of 28 broilers each. Depending on the type of addition per kg basal diet, treatments were C (no other addition), PL (108 colony forming units of probiotic), PH (109 colony forming units of probiotic) and A (2.5 mg avilamycin). Overall bodyweight gain was better (P = 0.002) in PL and PH than in the control (2082 g) by 8.7% and 7.5%, respectively, while treatment PL did not differ from A (2341 g), which showed the highest bodyweight gain. The ileal and total-tract apparent digestibility of DM and the apparent metabolisable energy content corrected for N improved linearly (P ≤ 0.05) with the probiotic level. Fluorescent in situ hybridisation analysis showed caecal Bifidobacterium levels to increase linearly (P = 0.006) with the probiotic level. Probiotic administration resulted in altered caecal VFA patterns compared with the control. Gender effects (P ≤ 0.05) were noted for caecal levels of C. histolyticum group, Bacteroides fragilis group and Streptococcus spp., while interactions (P ≤ 0.05) of treatment with gender were seen for Bifidobacterium and all VFA components, except for acetate. In conclusion, beneficial effects on bodyweight gain, DM digestibility, apparent metabolisable energy content corrected for N, caecal Bifidobacterium levels and VFA patterns were noted with both probiotic inclusion levels.

Low nutritive quality of own-mixed chicken rations in Kampala City, Uganda

Chicken production is popular in Kampala City, Uganda. Indeed about 70 % of all poultry products consumed in Kampala are produced locally. However, the high cost of feed is a major limiting factor. As a consequence, chicken farmers are formulating and mixing their own feeds. However, these own-mixed feeds may not meet recommended nutrient levels. We therefore studied five classes of own-mixed chicken feeds: broiler starter, broiler finisher, chick mash, grower mash, and layer mash. Samples of the chicken feeds were collected from farmers in and around Kampala City. We analyzed crude protein, ether extract, crude fiber, total starch, ash, calcium, phosphorus, and gross energy contents of the feeds. The apparent metabolizable energy content was calculated. We compared data with dietary requirements recommended for chickens in the tropics. Results show that own-mixed rations contained 21.9–36.3 % less protein than minimum recommendations. Broiler rations contained 16.2–20 % less metabolizable energy than minimum recommendations, and their crude fiber content was 37.5–50 % higher than the maximum recommendation. Layer mash contained 66.7 % less calcium and 17.5 % less metabolizable energy than minimum recommendations. All the five classes of own-mixed chicken rations were very high in ash content, ranging from 17.0 to 21.2 %. We conclude that own-mixed chicken rations do not conform to the dietary recommendations. There is therefore a need to give chicken farmers training on feed formulation and mixing.

Effect of inclusion of porcine mucosa hydrolysate in diets varying in lysine content on growth performance and ileal histomorphology of broilers

Porcine mucosa hydrolysate sprayed into a soybean meal carrier (PMH) is a co-product of heparin production from clean endothelial digestive tissues. An experiment was conducted to evaluate growth performance and ileal morphology of broilers fed diets with or without PMH inclusion. There were 8 dietary treatments arranged as a 2×4 factorial with two levels of PMH (0 vs. 25g/kg diet) and four levels of lysine (Lys; 11, 12, 13 and 14g/kg diet). Diets were formulated to have similar apparent metabolizable energy (AMEn) content and within each Lys level, the indispensable amino acid to AMEn ratio was maintained constant. Birds received the experimental diets from d 1 to 21 and then, a common commercial finisher diet without PMH inclusion from d 21 to 32. Each treatment was replicated five times and the experimental unit was the pen with 32 chicks. An interaction between PMH inclusion and Lys content of the diet was detected for body weight gain (BWG) from d 1 to 7; PMH inclusion improved BWG (P=0.013) in all cases but the effects were more noticeable in birds fed the low Lys diets (P<0.05 for the interaction). PMH inclusion did not affect BWG after this age but improved (P<0.01) feed to gain ratio (F:G) from d 1 to 21. From d 1 to 21, an increase in dietary Lys improved BWG (P<0.001) but F:G was not affected. From d 22 to 32, when all bird received a common finisher diet, growth performance was not affected by type of diet fed during the starter period. At d 14, villus height and crypt depth of the ileum were not affected by dietary treatment. The results indicate that the inclusion of 25g PMH/kg diet improved F:G from d 1 to 21 and BWG during the first 7 d of life. From d 1 to 21, broilers required at least 13g Lys/kg diet to optimize growth performance.

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

BackgroundThis 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.MethodsTwenty-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.ResultsResults 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).ConclusionsThis 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.

The effect of soy oligosaccharide extraction on diet digestibility, faecal characteristics, and intestinal gas production in dogs

This study aimed at evaluating the coefficients of total tract apparent digestibility (CTTAD) and metabolisable energy (ME) content of dog foods containing different soybean protein products, as well as the faecal characteristics and intestinal gas production of dogs consuming these diets. The following soybean products were added at 300g/kg of diet: soybean meal (SBM), soy protein concentrate (SPC) with 600g crude protein (CP)/kg (SPC600), SPC with 700gCP/kg (SPC700), hydrolysed SPC700 (HSPC), and soy protein isolate (SPI). The CTTAD and faecal characteristics were determined in six dogs according to a 6×6 Latin square design. Intestinal gas production was evaluated by radiography of 16 dogs fed the reference diet and diets containing 300g SBM, SPC700, or SPI/kg. Crude protein digestibility of SBM, SPC600, SPC700, HSPC, and SPI was 0.898, 0.839, 0.852, 0.906, and 0.988, respectively. Soy protein isolate presented the highest ME content (21.26MJ/kg, P<0.001) and SPC600, the lowest ME (14.15MJ/kg, P<0.001). Dogs fed the reference and the SPI diets presented harder faeces and higher faecal pH (P<0.001). Soybean meal produced the highest intestinal gas volume (P<0.05), while there was no difference among the other treatments (P>0.05). The removal of soybean oligosaccharides reduces intestinal gas production in dogs. However, soybean ethanol-insoluble fibres must be removed to increase protein digestibility and ME content, as well as to improve the faecal texture of dogs.

Prediction of energetic value of wheat and triticale in broiler chicks: A chick bioassay and an in vitro digestibility technique

Variation in apparent metabolizable energy (AME) of diets is a concern in poultry feeding. Thus, predicting variations in AME content of cereal grains is important, because this will allow a more accurate diet formulation. Eight samples, six wheat and two triticale, were collected from western Canada and a modified chick bioassay was used to determine their nitrogen-corrected AME (AMEn) content for broiler chicks. A total of 768 one-d-old male broiler chicks were randomly assigned to 8 dietary treatments (8 cages per treatment and 12 chicks per cage). Birds were fed a starter diet from 0 to 7d of age and experimental diets were fed from 7 to 13d of age. The experimental diets were composed of 80% of test sample and the remaining 20% was a combination of other ingredients held constant across diets. Digestibility of nutrients and energy differed significantly among birds fed the experimental diets. The AMEn values of the test samples determined in the bioassay ranged from 12.7MJ/kg of DM for Canada Western Soft White Spring sample to 14.6MJ/kg of DM for Canada Western Amber Durum sample. Energetic values of the 8 test samples were also evaluated using a two-step in vitro digestibility technique simulating digestive processes in broiler chicks. In vitro AME value of the test samples were calculated and related to in vivo AMEn by regression analysis. The equation for prediction of in vivo AMEn based on in vitro AME was: In vivo AMEn (MJ/kg of DM)=5.4108+0.7016×in vitro AME (R2=0.81, standard error of prediction (SEP)=0.22MJ/kg, P=0.002). Inclusion of other energy-related characteristics of test samples (e.g., starch, ether extract, and crude protein) into the regression equation increased the R2 and decreased the SEP. Specifically, inclusion of neutral detergent fiber, ether extract, starch, and crude protein of samples together with the in vitro AME resulted in the strongest prediction equation for in vivo AMEn (R2=0.99, SEP=0.05MJ/kg, P=0.014). The predicted in vivo AMEn of test samples ranged from 12.7 to 14.5MJ/kg of DM. In conclusion, this in vitro digestibility technique accurately predicted in vivo AMEn of wheat and triticale 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 (NIRS).

The effect of variety and growing conditions on the chemical composition and nutritive value of wheat for broilers.

The aim of this study was to examine the effect of variety and growing conditions of wheat on broiler performance and nutrient digestibility. One hundred and sixty-four wheat samples, collected from a wide range of different sources, locations, varieties and years, were analyzed for a range of chemical and physical parameters. Chemical and physical parameters measured included specific weight, thousand grain weight (TG), in vitro viscosity, gross energy, N, NDF, starch, total and soluble non-starch polysaccharides (NSP), lysine, threonine, amylose, hardness, rate of starch digestion and protein profiles. Ninety-four of the wheat samples were selected for inclusion in four bird trials. Birds were housed in individual wire metabolizm cages from 7 to 28 d and offered water and feed ad libitum. Dry matter intake (DMI), live weight gain (LWG) and gain:feed were determined weekly. A balance collection was carried out from 14 to 21 d for determination of apparent metabolizable energy (AME), ME:gain, DM retention, oil and NDF digestibility. At 28 d the birds were sacrificed, the contents of the jejunum removed for determination of in vivo viscosity and the contents of the ileum removed for determination of ileal DM, starch and protein digestibility. The wheat samples used in the study had wide-ranging chemical and physical parameters, leading to bird DMI, LWG, gain:feed, ME:GE, AME content and ileal starch and protein digestibility being significantly (p<0.05) affected by wheat sample. A high level of N fertilizer application to the English and NI wheat samples tended to benefit bird performance, with increases of up to 3.4, 7.2 and 3.8% in DMI, LWG and gain:feed, respectively. Fungicide application also appeared to have a positive effect on bird performance, with fungicide treated (+F) wheat increasing bird DMI, LWG and gain:feed by 6.6, 9.3 and 2.7%, over the non-fungicide treated (-F) wheats. An increase (p<0.1) of 9.3% in gain:feed was also observed at the low seed rate of 40 compared to 640 seeds/m2. It was concluded that the type of wheat sample and environmental growing conditions significantly affects bird performance when fed wheat-based diets.

Influence of source of fat and supplementation of the diet with vitamin E and C on performance and egg quality of laying hens from forty four to fifty six weeks of age

Two experiments (Exp.) were conducted to determine the apparent metabolizable energy (AME) content of refined soybean oil (SO), recycled soybean oil (RSO) and acidulated soybean oil soapstock (ASO) and the effects of inclusion of vitamin E and C in diets containing 35g/kg of these oils on performance and egg quality of Hy-Line W-36 hens from 44 to 56 weeks of age. In Exp. 1, the AME of the three oils was estimated in adult cockerels (n=6) either by multiplying the digestibility of the oil by its gross energy value or by difference between the AME values of the basal diet and that of a diet that included 50g/kg of the oil. The estimated AME of the SO, RSO and ASO oils were 37.32, 37.13 and 32.85MJ/kg when measured directly from oil digestibility coefficients and 38.19, 37.44 and 33.33MJ/kg when calculated by difference, respectively. In Exp. 2, there were 12 dietary treatments arranged factorially with three oil sources, two levels of supplemental vitamin E (10 vs. 250IU/kg) and two levels of supplemental vitamin C (0 vs. 250mg/kg). Each diet was replicated five times and the experimental unit was a cage with five hens. Diet did not affect laying hen performance or egg quality traits in any of the periods considered. It is concluded that when well processed, recycled soy oil and acidulated soy oil soapstock are good alternatives to refined soybean oil in diets for laying hens. Under the conditions of this research, the supplementation of the diet with extra amounts of vitamin E and C to increase egg production or egg quality was not justified.

Metabolizable energy and nutrient digestibility of detoxified castor meal and castor cake for poultry

This experiment aimed to determine the metabolizable energy and the digestibility of detoxified castor meal and castor cake nutrients for broilers. A total of 180 Cobb-500TM broilers from 21 to 32 days of age was randomly distributed in three treatments with six replicates of 10 broilers - 5 males and 5 females. The experimental treatments were a reference-diet and two test-diets composed of 80% of reference-diet and 20% of detoxified castor cake or castor meal. The adaptation period ranged from 21 to 27 days of age and the total excreta collection period ranged from 28 to 32 days of age. The detoxified castor meal presented apparent metabolizable energy of 2,032 kcal/kg of natural matter, apparent metabolizable energy corrected for nitrogen balance of 1,829 kcal/kg of natural matter and the digestibility coefficients of 57.8% dry matter, 68.4% crude protein, 10.5% crude fiber, 35.9% nitrogen free extract, 80.0% ether extract and 26.6% ash. In the detoxified castor cake, the apparent metabolizable energy content was 2,550 kcal/kg of natural matter, the nitrogen corrected apparent metabolizable energy balance was of 2,320 kcal/kg of natural matter and the digestibility coefficients of 60.6% for dry matter, 77.2% for crude protein, 14.0% for crude fiber, 45.7% for nitrogen free extract, 85.4% for ether extract and 28.2% for ash. The metabolizable energy and digestibility of nutrients in detoxified castor cake are higher than in the detoxified castor meal.

Nutritional evaluation and utilisation of quality protein maize, Nityashree hybrid maize, and normal maize in broiler chickens

1. Three experiments were conducted to determine the apparent metabolisable energy, apparent digestible amino acid values, and utilisation of three maize varities in chickens: quality protein maize (QPM), hybrid maize Nityashree (HMN) and normal maize (NM). 2. There was no significant difference in the apparent metabolisable energy (AME) content amongst the three varieties of maize. 3. Lysine and threonine digestibilities were significantly higher in QPM compared to either HMN or NM. No difference in the digestibilities of other amino acids occurred among the three different maize varieties. 4. There was no difference between diets containing NM or HMN for body weight gain (21 and 40 d of age) and overall feed conversion ratio (0–40 d), but values were significantly higher for QPM (and Lys-supplemented NM) diets. The relative weights of dressed meat yield and giblets were unaffected by dietary replacement of NM with QPM, HMN, or Lys supplementation of the NM diet. However, abdominal fat content decreased and breast meat yield increased with both dietary replacement of NM with QPM and Lys supplementation of the NM diet. 5. The concentration of protein in serum was significantly increased by dietary replacement of NM with QPM. Adding Lys to the NM based diet significantly increased the Ca concentration in serum compared with NM or HMN diets. However, the highest concentration of Ca in serum was found in the QPM diet. The concentration of total cholesterol in serum significantly decreased by either replacing NM with QPM or adding Lys to the NM based diet, compared with the NM diet. 6. These results suggested that the feeding value of quality protein maize was superior to normal maize, while the feeding value of hybrid maize Nityashree was similar to that of normal maize.

Apparent digestible and metabolizable energy content of glycerol in feed of growing pigs

Two experiments were conducted each with the same 12 pigs in the growing and finishing phase to determine the apparent digestible (DE) and metabolizable energy (ME) content of crude glycerol (86.76%) in feed compositions. Animals were randomly selected and placed into individual metabolism crates. Pigs fed basal diet supplemented with 0%, 5% or 10% of crude glycerol. A repeated 3×3 Latin square experimental design was applied. After an adaptation period of 10days, feces and urine samples were collected for 5days. Gross energy (GE) content of feed, feces and urine samples were measured in bomb calorimeter. The determined apparent DE and ME value of crude glycerol were 13.827 and 13.475MJ/kg, respectively. These values represent 90.3% and 88.0% of GE. The results agree with DE and ME content of glycerol published by other researchers. DE and ME are not dependent on weight of pigs in the range of 25–85kg and do not vary by the rate of crude glycerol in the diet (5% or 10%). According to our experiments diets different from usual corn-soybean meal feed did not influence utilization of glycerol.Feed grade glycerol can be considered a perspective feed component in diet of fattening pigs.

Short Communication: Near infrared reflectance spectroscopy accurately predicts the digestible energy content of barley for pigs

Zijlstra, R. T., Swift, M. L., Wang, L. F., Scott, T. A. and Edney, M. J. 2011. Short Communication:Near infrared reflectance spectroscopy accurately predicts the digestible energy content of barley for pigs. Can. J. Anim. Sci. 91: 301–304. Density, chicken apparent metabolizable energy (AME), and near infrared reflectance spectroscopy (NIRS) were tested to predict the widely varying swine digestible energy (DE) content of barley. The DE content of 39 barley samples ranged from 2686 to 3163 kcal kg−1 (90% DM) in grower pigs. The R2 between DE content and density (0.14) and broiler chicken AME content (0.18 and 0.56, without and with enzyme, respectively) was low. In contrast, the coefficient of determination to predict swine DE content for ground barley samples using NIRS was respectable for external validation (R2=0.74) and internal cross validation (1-VR=0.79), but more robust calibrations should be developed for commercial application.

Influence of feed form and conditioning temperature on performance, apparent metabolisable energy and ileal digestibility of starch and nitrogen in broiler starters fed wheat-based diet

The influence of feed form and conditioning temperature on performance, apparent metabolisable energy (AME) and ileal digestibility of starch and nitrogen in broilers fed wheat-based starter diet were examined in this study. Two feed forms (mash and pellet) and four conditioning temperatures: 20 °C (dry-conditioning), 60, 75 and 90 °C (steam-conditioning) were evaluated in a 2 × 4 factorial arrangement of treatments. In mash diets, weight gain of birds fed the diet conditioned at 60 °C was higher (P<0.05) than those fed diets conditioned at 75 and 90 °C and similar (P>0.05) to those fed diet conditioned at 20 °C. In pelleted diets, while steam-conditioning increased (P<0.05) the weight gain compared to dry-conditioning, birds fed diets conditioned at 60, 75 and 90 °C had similar (P>0.05) weight gains. Pelleting increased (P<0.001) the feed intake. Birds fed diets conditioned at 20 °C had lower (P<0.01) feed intake than those fed diets conditioned at 60 and 90 °C and similar (P>0.05) to those fed diets conditioned at 75 °C. In mash diets, birds fed the diet conditioned at 90 °C had higher (P<0.05) feed per unit gain than those fed diets conditioned at 20 and 60 °C, but similar (P>0.05) to those fed the diet conditioned at 75 °C. In pelleted diets, while steam-conditioning decreased (P<0.05) the feed per unit gain, birds fed steam-conditioned diets (at 60, 75 and 90 °C) had similar (P>0.05) feed per unit gain. Pellet durability and hardness increased (P<0.001) with increasing conditioning temperatures. Pelleting reduced (P<0.001) the coefficient of ileal apparent digestibility (CIAD) of nitrogen of the diets. Coefficient of ileal apparent nitrogen digestibility of the diets conditioned at 60 and 75 °C was similar and higher (P<0.01) than those conditioned at 20 and 90 °C. In mash diets, the CIAD of starch in the diet conditioned at 60 °C was higher (P<0.05) than diet conditioned at 90 °C, but similar to those conditioned at 20 and 75 °C. In pelleted diets, those conditioned at 60 and 90 °C had higher (P<0.05) CIAD of starch than the diet conditioned at 20 °C, but similar to the diet conditioned at 75 °C. Higher (P<0.001) apparent metabolisable energy values were determined for mash diets. The AME content of diets conditioned at 60 °C was similar to those conditioned at 75 °C and higher (P<0.05) than diets conditioned at 20 and 90 °C. In both feed forms, the diet conditioned at 90 °C had the highest (P<0.05) gelatinised starch content. In mash diets, while the diets conditioned at 20, 60 and 75 °C had similar resistant starch content, the diet conditioned at 90 °C had the highest (P<0.05) resistant starch content. In pelleted diets, the diets conditioned at 20 and 90 °C had higher (P<0.05) resistant starch content than the diet conditioned at 60 °C, but similar to the diet conditioned at 75 °C. Overall, the current results suggest that while in mash diets steam-conditioning at 60 °C improved weight gain and feed intake, increasing conditioning temperatures per se had negative effects on nutrient utilisation and, weight gain and feed per unit gain of broiler starters. But the deterioration in performance parameters caused by conditioning at higher temperatures was restored when steam-conditioned mash diets were pelleted.

Effect of fat type and lysophosphatidylcholine addition to broiler diets on performance, apparent digestibility of fatty acids, and apparent metabolizable energy content

A completely randomized design study with a 3×2 factorial arrangement was conducted to evaluate the effects of three different fat sources (soybean oil, tallow, and poultry fat) with or without emulsifier supplementation on performance, coefficient of total tract apparent digestibility (CTTAD) of fatty acids, and apparent metabolizable energy (AME) content in broiler chickens. Two hundred and fifty-two one-day-old male Arbor Acres broiler chickens were randomly divided into 6 different treatments: (T1) basal diet containing soybean oil without lysophosphatidylcholine (LPC) supplementation, (T2) basal diet containing soybean oil with LPC supplementation, (T3) basal diet containing tallow without LPC supplementation, (T4) basal diet containing tallow with LPC supplementation, (T5) basal diet containing poultry fat without LPC supplementation, and (T6) basal diet containing poultry fat with LPC supplementation. Body weight gains from broiler chicks fed diets containing tallow were lower (P<0.05) than the body weight gains from chicks that were fed diets containing soybean oil or poultry fat in both the starter and grower periods. Birds fed diets containing tallow had the highest FCR (P<0.05), followed by the birds that were fed diets containing poultry fat, and soybean oil. The CTTAD of C16:0, C18:2, and C18:3n3 was greater (P<0.05) for broilers fed diets containing soybean oil than for those fed diets containing tallow or poultry fat in the starter period. The addition of LPC increased (P<0.05) body weight gain of broiler chickens in the starter period and the AME of the diets in the grower period, and tended to reduce FCR (P=0.072) in the starter period. LPC supplementation increased (P<0.05) the CTTAD of C16:0, C18:1n7 and C18:1n9 in the starter period, and of C18:2, and C18:3n3 in the grower period (P<0.05). There were no significant interactions between fat sources and the addition of LPC. These data indicated that LPC supplementation can improve body weight gain of broiler chickens in the starter period. This effect may be associated with an increase of CTTAD of FA due to LPC activity.

The prediction of apparent metabolisable energy content of oil seeds and oil seed by-products for poultry from its chemical components, in vitro analysis or near-infrared reflectance spectroscopy

Regression models including chemical composition, in vitro digestibility and near-infrared reflectance spectroscopy (NIRS) were compared to predict the energy content of several feed ingredients for poultry. The nitrogen-corrected apparent metabolisable energy content (AMEn) and its proportion on total gross energy (AMEn/GE) were determined in 52 batches of six protein concentrates; samples were randomly obtained from a poultry feed manufacturing plant throughout a 3-year period. A preliminary trial was also designed to adapt in vitro methods for prediction of in vivo energy values for poultry. Mean concentrations of AMEn of the ingredients studied ranged from 5.29 to 14.7 MJ/kg DM and those of AMEn/GE from 0.260 to 0.609. The most precise model for prediction of AMEn and AMEn/GE values for the whole data analysed was that based on NIRS equations ( R cv 2 = 0.952 and 0.926 , respectively). The best single chemical predictor was the concentration of neutral detergent fibre (NDF) in each ingredient ( R 2 = 0.721 and 0.736, respectively). Further inclusion of ether extract content increased R 2 to 0.945 and 0.902 for AMEn and AMEn/GE, respectively. A model including linear and quadratic effects of in vitro organic matter digestibility (ivOMd) provided a slightly inferior prediction of AMEn/GE values ( R 2 = 0.865). However, the prediction of AMEn from ivOMd was clearly lower ( R 2 = 0.756), as variations among batches of GE concentration (from 19.0 to 24.9 kcal/kg DM) were poorly related to in vitro digestibility values. All the indirect methods used were useful to explain part of the variability of the energy value of the ingredients studied, although the best results were generally obtained from the NIRS equations. Otherwise, the significance of the prediction depended directly on the variability of the different data set studied.

The effect of a β-mannanase-based enzyme on growth performance and humoral immune response of broiler chickens fed diets containing graded levels of whole dates

The use of low-quality whole dates in broilers' diets was evaluated. The apparent metabolizable energy (AMEn) of whole dates and date pits was determined with or without a beta-mannanase-based enzyme (Hemicell--a registered trademark of ChemGen Corp., Gaithersburg, MD. Dried Bacillus lentus fermentation solubles with 158 million units/kg minimum enzyme activity. Recommended usage rate is 0.4 g kg(-1) of feed. ChemGen Corp., Gaithersburg, MD, USA). A 3 x 2 factorial arrangement consisting of whole dates (0, 175, and 350 g kg(-1)) and enzyme (0 or 0.4 g kg(-1)) was performed to assess the effect of the enzyme on the nutritive value of whole dates (experiment 2) in broilers' diet. Enzyme improved AMEn contents of the whole dates and date pits. The diets containing 175 or 350 g kg(-1) whole dates produced body weight gain (BWG) similar to those obtained without dates. Enzyme improved BWG and feed conversion ratio throughout the experimental period. In conclusion, whole dates can be included in broiler diets at levels up to 350 g kg(-1). In addition, beta-mannanase supplementation would have beneficial effects on performance and immunity in birds fed on corn-soy or corn-soy-whole dates diets.

Metabolizable Energy Content of Meat and Bone Meal in Corn-Soybean Meal or Corn, Wheat and Soybean Meal Diets for Broilers

The experiment was conducted to determine the apparent metabolizable energy (AME) or nitrogen-corrected metabolizable energy (AMEn) content of a high protein meat and bone meal (MBM) in broiler diets contain graded levels of wheat. Two hundred eighty-eight 14-d old broilers were allocated to six dietary treatments in a randomized complete block design and a2×3 factorial arrangement of treatments namely two levels of MBM (0 and 80g/kg) and three levels of wheat (0, 100 and 200g/kg). Wheat replaced part of corn and soybean meal and MBM was added at 0 or 80g/kg at each level of wheat. The birds received the diets for 7 d, and excreta were collected on d 19 to 21. The substitution of corn and SBM by wheat (200g/kg) increased the total NSP content in the diet by 11g/kg. There was a 5% decrease in both AME and AMEn when the level of wheat in the corn-SBM was increased to 200g/kg but this decrease was not significant. On the average, irrespective of wheat levels, AME and AMEn of the MBM were 2,734 and 2,586kcal/kg, respectively. Dietary AME and AMEn were greater in the diets with 200g/kg wheat compared to corn-SBM diet (P<0.05), and N excretion was greater (P<0.01) in the diets with MBM. Our results suggest that replacing part of corn and soybean meal with up to 200g/kg of wheat similar to what was used in the current study would have no effect on metabolizable energy of MBM.

A comparison of the prediction of apparent metabolisable energy content of starchy grains and cereal by-products for poultry from its chemical components, in vitro analysis or near-infrared reflectance spectroscopy

Regression models including chemical composition, in vitro digestibility and near infrared reflectance spectroscopy (NIRS) were compared in order to predict the energy value of several feed ingredients for poultry. The nitrogen-corrected apparent metabolisable energy content (AMEn) in cockerels and its proportion on total gross energy (AMEn/GE) were determined in 94 batches from six starchy grains and six cereal byproducts. Two preliminary trials were also designed to adapt in vitro methods for prediction of in vivo energy values for poultry. Mean concentrations of AMEn of the ingredient studied ranged from 2,464 to 3,595 kcal/kg DM, and those of AMEn/GE from 53.7 to 80.0%. The most precise model of prediction of AMEn and AMEn/GE values was that based on NIRS equations (R2cv = 0.823 and 0.861, respectively). The best single chemical predictor of these energy values was the neutral detergent fibre concentration (R2 = 0.616 and 0.736, respectively). Further inclusion of ether extract and ash contents in the AMEn model and those of starch and ether extract in the AMEn/GE model allowed increasing coefficients of determination up to 0.791 and 0.839, respectively. A model including linear and quadratic effects of in vitro organic matter digestibility (IVOMd) provided a similar prediction of AMEn/GE values (R2 = 0.833). However the prediction of AMEn from IVOMd was worse (R2 = 0.62), as variations among batches of GE concentration (from 4,225 to 5,896 kcal/kg DM) were little related to in vitro digestibility values.