True Metabolizable Energy Values Research Articles

Metabolizable energy value and effect on amino acid availability of medium-chain triglycerides in diets fed to chickens of different ages

Three experiments were conducted to determine the energy value and digestibility of medium-chain triglycerides (MCT) in chickens. Triacylglycerol with capric acids (C10-TG) and triacylglycerol with capric and caprylic acids (C10C8-TG) were provided as the MCT sources. Sixty 3-day-old broiler chicks and 25 adult roosters were provided for the determination of nitrogen-corrected true metabolizable energy (TMEn) of MCT. Forty 3-week-old broiler chicks were provided for the determination of nitrogen-corrected apparent metabolizable energy (AMEn) of MCT. True amino acid availability of amino acids (TAAA) of a diet with MCT was determined using adult roosters. The TMEn of C10-TG (37.11–38.45 MJ kg −1) was not significantly different from that of yellow grease (YG, 39.29–40.54 MJ kg −1), a long-chain triglycerides (LCT), in 3-day-old chicks. In 3-week-old chickens, the AMEn of C10-TG (32.04 MJ kg −1) was comparable with that of YG (32.00 MJ kg −1). The TMEn (36.02–36.44 MJ kg −1) and AMEn (33.76 MJ kg −1) of C10C8-TG were higher to a certain extent than YG (AMEn: 32.00 MJ kg −1) and C10-TG (TMEn: 25.90–31.12 MJ kg −1; AMEn: 32.04 MJ kg −1). Digestibility of lipids in the basal diet (68.1%) and that of C10-TG (96.3–98.5%) was low in 3-day-old chicks as compared with those in roosters (78.8% and 100.0–107.9%). The digestibility of MCT (96.3–107.9%) was higher than YG (94.0–94.6%), irrespective of the age of chickens. TAAA was not influenced by the inclusion of MCT in the diet. It is suggested that the digestibility of C10-TG and C10C8-TG is higher than that of YG and the TMEn and AMEn values are comparable with that of YG. Therefore, MCT is a potential fat source for chickens, particularly for very young chicks.

Carob pod (Ceratonia siliqua) meal in geese diets.

1. The apparent and true metabolisable energy values of carob pods meal for geese were measured to be 6.1 MJ/kg and 6.6 MJ/kg respectively. 2. Performance from 5 to 12 weeks was examined in geese fed on four diets containing 0, 100, 200 and 300 g/kg of carob pods meal. 3. The inclusion of carob pods meal up to 200 g/kg in geese diets did not affect the performance. 4. At 300 g/kg performance was highly depressed. 5. The digestibility of protein in the diets decreased linearly with an increase in the level of inclusion of carob pods meal. 6. The length of small intestine, large intestine and caeca and the weight of gizzard expressed per kg of body weight increased with an increase in the level of carob pods meal, which is rich in fibre, in the diets.

True Metabolizable Energy Estimates for Wild and Game-Farm Mallards

Potential differences in metabolism of food energy by wild and game-farm mallards (Anas platyrhynchos) may confound assays for true metabolizable energy (TME) of foods fed to either strain of mallards. Consequently, we compared estimates of TME for a commercial diet between captive wild-strain and game-farm mallards. Mean values for body mass and TME were similar (P≥0.2) between mallard strains, but mean TME was slightly more variable for game-farm (CV=8.5%) than wild mallards (CV=5.9%). Our pooled mean estimate of TME (2.76±0.07 kcal/g) was similar to several other reported values for mallards fed a comparable diet, but intermediate among TME values of natural foods or cereal grains ( 3 kcal/g) consumed by Anas species

The nutritive value of industrial by-products for poultry

The metabolizable energy (ME) and partly also the digestibility of several industrial by-products, mainly originating from grain, were determined in trials with adult cockerels. Five experiments were performed using a conventional total collection procedure, and test ingredients were substituted for 25-40 % of the basal diet. The nitrogen-corrected apparent (AMEn) and true (TMEn) metabolizable energy values of distillers’ dried grains (DDG) and distillers’ dried grains with solubles (DDGS) derived from barley, wheat and rye varied from 7.85 to 11.8 and from 7.98 to 12.0 MJ/ kg DM, respectively. The highest MEn values were observed in the dehulled barley-derived products. The digestibility of crude protein (CP) was 62-83 and that of carbohydrates 25-50 %, the latter being lowest for feeds originating from whole barley grain. The results indicated that distillers’ feeds derived from dehulled grain, especially barley, are satisfactory energy sources for poultry diets. Dried barley protein (BP 1, CP 38 %), oats protein (CP 44 %) and distillers’ solids (CP 58 %) from the integrated ethanol starch process, as well as dehulled barley and oats proved to be excellent energy feeds containing AMEn 14.9, 18.6, 15.0, 14.2 and 14.6 MJ/kg DM, respectively. The TMEn values for BPI and dehulled grains were 15.3, 14.4 and 14.8 MJ/kg DM. Supplementation with enzymes did not significantly improve the ME value of dehulled barley. The AMEn values for barley protein (BP2, CP 27 %), barley bran and barley molasses obtained from the starch process, and wheat feed meal from the milling industry, were 13.3, 8.52, 13.5 and 10.6 MJ/kg DM, respectively. The lowest ME values were obtained for samples of wheat bran, dried potato pulp and malt sprouts: AMEn 6.09, 6.23 and 6.01; TMEn 6.15, 6.07 and 6.01 MJ/kg DM, respectively.

Nutritional value of cassava meal in diets for geese

Three trials were conducted with geese of the Rhine breed (strain of Artiguéres). In the first trial, the apparent and true metabolizable energy values adjusted to zero nitrogen balance (AMEn and TMEn, respectively) of cassava meal for growing geese at the age of 9 weeks were measured. The AMEn and TMEn were determined to be 12.48 MJ kg −1 and 12.59 MJ kg −1, respectively. In the second trial, the metabolizable energy value and protein digestibility of diets containing 0, 150, 300 and 450 g kg −1 cassava were measured. There was no difference between the determined and calculated energy values for diets, but protein digestibility was found to decrease with an increase in the level of cassava meal in the diets. In trial 3, diets containing the same levels of cassava meal as those of trial 2 were used to study effects on performance of geese from 5 to 12 weeks of age. The inclusion of up to 450 g kg −1 cassava meal in geese diets had no significant effect on animal performance and carcass quality.

Effect of Kernel Density on the Apparent and True Metabolizable Energy Value of Corn for Chickens

Five samples of corn selected to vary widely in kernel density (test weight per unit volume) were assayed for AMEn with male broiler chickens at 4 wk of age by regression analysis of a multilevel assay and for TMEn with adult White Leghorn roosters. The kernel densities (kilograms per hectoliter), AMEn, and TMEn (kilocalories per gram of DM) values of the corn were, respectively, 72, 3.68, and 3.96; 71, 3.72, and 3.95; 68, 3.66, and 3.90; 62, 3.64, and 3.88; 60, 3.54, and 3.68. Positive relationships were established between AMEn and TMEn (r = .974, P<.01) or kernel density (r = .875, P<.05). The assay for TMEn provided a simple, rapid and sensitive method for estimating the AMEn content of corn for chickens. The small (4%) variation in AMEn relative to a large (20%) variation in kernel density precludes the use of kernel density for estimating the AMEn content of corn.

The antinutritive effect of proanthocyanidin-rich and proanthocyanidin-free hulls from field beans on digestion of nutrients and metabolisable energy in intact and caecectomised cockerels

Three white flowered (proanthocyanidin-free) and three coloured flowered (proanthocyanidinrich) varieties of field beans were dehulled to give pure cotyledons and pure hulls. Cockerels that had been starved for 48 h received directly into the crop the following three diets with cotyledon to hull ratios of 100:0, 80:20 or 50:50 in amounts of 30, 37.5 and 60 g, respectively. A control group of birds received 50 g glucose only. Excreta voided over 72 h were quantitatively collected and freeze dried. True metabolisable energy values for the diets were calculated from the gross energy of diets and excreta. True digestibility of protein, starch and lipid was calculated from the quantitative measurement of amino acids, starch and lipid in diets and excreta. Proanthocyanidin-free hulls were mainly composed of non-starch polysaccharides and their ingestion caused a small reduction in the digestibility of protein and starch, the highest level of hulls causing the largest reductions, 3.1 and 3.5%, respectively. Proanthocyanidin-rich hulls greatly reduced the digestibility of protein, starch and lipid, the highest level of hulls causing the largest reductions, 22.0, 23.5 and 9.3%, respectively. The true metabolisable energy values of diets were greatly reduced by the inclusion of both types of hulls, although proanthocyanidin-rich hulls caused the greatest reductions in metabolisable energy values. Caecectomy did not appear to affect the true metabolisable energy of diets nor the digestion of protein, starch or lipid.

Effect of Level of Feed Input on True Metabolizable Energy Values and Their Additivity

Four experiments were carried out to study the effect on the TMEn value of the amount intubed of corn (25, 50, and 75 g) field beans (Vicia faba, 25, 50, and 75 g) soybean meal (25 and 50 g), sugar (25, 50, 75, and 100 g), common vetch (Vicia sativa, 30 and 75 g), and chickling vetch (Lathyrus cicera, 30 and 75 g). The TMEn value of feedstuffs was not modified when the amount intubed was 50 g or more; however, data were inconsistent when intake was only 25 g. The TMEn value of field beans was the same among experiments (P>.05) when the amount intubed was 50g or more. The addition of corn to field beans or soybean meal did not modify their TMEn value but did reduce the precision. The additivity of TMEn values of several mixtures of corn with field beans or soybean meal was also studied. In general, the predicted values of the mixtures were not different (P>.05) from the values determined by direct intubation.The TMEn value of feedstuffs estimated from a regression model on feed intake was not different (P>.05) from the TMEn value obtained when 50 g or more were intubed. It is suggested that amounts of 50 g or more are preferable to intube Cornish roosters in TMEn assays. According to the results of the present study, the TMEn (MJ/kg DM, 1 MJ = .239 Mcal) value of the feedstuffs was soybean meal 12.7, sugar 16.0, common vetch 12.8, chickling vetch 11.5, corn (6.9% crude protein) 14.8, corn (9.3 g CP/100 g DM) 16.0, and field beans (34.9 or 27.1% CP) 12.5.

THE NUTRITIVE VALUE OF NAKED OATS FOR BROILER CHICKS AS AFFECTED BY DIETARY ADDITIONS OF OAT GUM, ENZYME, ANTIBIOTIC, BILE SALT AND FAT-SOLUBLE VITAMINS

Five experiments were conducted with broiler chicks to evaluate naked oat (NO) as a major dietary ingredient and to identify means of ameliorating its growth-depressing effects. Substituting naked oats at concentrations of 0–600 g kg−1 for corn in a broiler starter diet gave a dose-dependent decrease in weight gain and feed efficiency. Incorporation of β-D-glucanase into a NO diet increased growth of chicks presumed by decreasing β-glucan viscosity whereas increasing the β-glucan content of the diet by addition of oat gum or oat brans decreased rate of growth and feed efficiency. Autoclaving NO or supplementing a 600 g kg−1 NO diet with neomycin or penicillin increased weight gains, but feed efficiency effects were inconsistent. True metabolizable energy values for naked oats and oat bran as determined with chicks were 16.2 and 11.5 MJ g−1 dry matter, respectively. True availabilities of energy, ether extract and amino acids were reduced by, respectively, 10, 5 and up to 8% by addition of oat gum to naked oats and, 2.4, 24 and up to 8% by ethanol deactivation of oat bran enzymes. Supplementation of a NO diet with antibiotic, bile salt and water-miscible, fat-soluble vitamins in factorial combination demonstrated that reduced absorption of lipids, including fat-soluble vitamins may decrease energy values and growth in chicks fed naked oats. The β-glucan content of naked oats appears to be the factor responsible for poor utilization of the feedstuff by chicks. The effect of this factor was overcome by treatment with enzyme or to a lesser degree by dietary supplementation with antibiotics, bile salt or fat-soluble vitamins. Key words: Oat (naked), β-glucan, enzyme, autoclaving, bile salt, fat-soluble vitamin phytase, chick

Estimation of endogenous energy and nitrogen losses in the cockerel during fasting and postprandial

1. The endogenous energy (EEL) and nitrogen losses of adult cockerels were studied during both when the animals were starved and when they were fed on a highly digestible nitrogen-free diet. The birds were fed three intakes by intubation and the effects of these intakes were compared. 2. During the 48-h study, the excretion of energy (EEL) was found to be 49.4 kJ, when the birds were given food. When starved this estimate was considerably higher, 70.3 kJ. 3. When endogenous energy per 48 h was corrected to zero nitrogen balance (EEL0), the value of starved animals of 30.1 kJ was still considerably higher than the 13.4 kJ for fed birds. 4. It was concluded that feeding a nitrogen free, highly digestible diet reduces the excretion of endogenous energy. Thus determinations from starved birds appear to give biased estimates of EEL and EEL0. Hence, true metabolisable energy values would also be overestimated where endogenous energy values from starved birds were used.

Ileal and faecal energy digestibility coefficients of full-fat canola seed for swine

Experiments were conducted to determine the ileal and faecal apparent digestible energy (ADE) value of canola seed (CS) for pigs. In the first experiment, five barrows were cannulated at the ileum and given purified diets containing CS with dysprosium chloride as an inert marker. Digestibility of crude protein and lysine were also determined. In Experiment 2, ADE values for CS were determined using the mobile nylon bag technique (MNBT). The true metabolizable energy (TME) of CS was determined using adult cockerels to determine its value as a predictor of ADE for swine. The faecal ADE value for CS was 19.7 MJ kg −1 DM. The ileal ADE value for CS was 17.6 MJ kg −1 DM. The MNBT ADE value for CS was 17.1 MJ kg −1 DM. The TME value for CS was 19.93 MJ kg −1 DM. The ADE value of CS predicted from the TME value for CS was 16.85 MJ kg −1 DM, which was 4.2 and 14.5% lower than the ADE values derived by ileal and faecal collection methods. The linear equation determined from regression analysis that was used to predict ADE from TME was: Y=3.895-0.65X (r=0.91; d.f.=4; SEM=0.38, < 0.01) where X is TME and Y is the ADE value. Faecal digestibility coefficients for dry matter, energy, protein and lysine of CS were 71.7, 82.3, 62.6 and 75.9%, respectively, and those values determined by the ileal method were 59.7, 75.7, 69.5 and 72.1%, respectively.

Modified assay for true and apparent metabolisable energy based on tube feeding.

1. To improve the accuracy with which true metabolisable energy (TME) values of feedingstuffs are determined, a modification to the assay based on tube-feeding is proposed. 2. To ensure that the gastrointestinal tracts of the experimental birds are as empty as possible at the start of the assay it is recommended that the normal food is withdrawn 48 h before tube-feeding. 3. In order to partly alleviate the effects of starvation, all birds are given two doses of 25 g glucose (as an aqueous solution) about 40 and 16 h before tube-feeding. Birds, from which endogenous energy losses are to be derived, are fed 50 g glucose rather than given no food. 4. All birds are given 50 ml water by tube about 32 h after feeding to overcome any effects induced by low water intake. 5. A comparison of the two procedures with 8 feedingstuffs showed that the mean coefficient of variation was reduced from 5.5% to 1.5% for TME and from 4.7% to 1.8% for TME.

Chemical, nutritive, deoxynivalenol and zearalenone content of corn relative to the site of inoculation with different isolates of Fusarium graminearum

AbstractKernels from two samples of 18 ears of corn were hand‐shelled into three fractions (Fl, F2 and F3) relative to the site (F3) where the ears had previously been inoculated with one of four isolates of Fusarium graminearum (Schwabe). F3 and Fl were from the nearest and remotest parts of the ear, respectively, to the inoculation site. Ears of uninoculated control corn were processed in the same manner. The resulting 30 samples were analysed, after grinding (20 mesh), for deoxynivalenol (DON), zearalenone (ZEA), ergosterol (EGS), dry matter (DM), 200 kernel weight, Kjeldahl nitrogen (N), ether extract, ash, sugar, starch, acid and neutral detergent fibre (ADF, NDF, respectively), cellulose, hemicellulose and lignin. The true metabolisable energy (TME), TME corrected to zero N balance (TMEn), true available amino acid (TAAA) and true DM digestibility (TDMD) contents of these samples and corn to which 4, 16 or 64 mg purified DON kg−1 were added, were determined using adult White Leghorn chickens.The DON, ZEA, EGS, N and ash contents were higher (P&lt;0.001), and ether extract, TME and TMEn values were lower (p&lt;0.01) in F3 than in Fl. Higer avilabilites accured for aspartic and glutamic acids, isoleucine, leucine and histidine in F2 and F3 than F1 (P&lt;0.05). Carbohydrate and fibre values varied little (p&gt;0.05) among fractions either within or among incoulation treatments. Sources of Fusarium inoculate influenced (P&lt;0.05) the DON, ZEA, N, fat and TDMD of the corn. The TMEn and total TAAA of corn decreased (P&lt;0.001) when purified DON was added. Moderate relationships (r=0.57−0.73) occurred between DON and ZEA, EGS and N. In general, these results are similar to those for wheat, and indicate that chemical and nutritive content of feedingstuffs may be increased when they are infected by toxigenic fungi.

Digestion of starch and fibre carbohydrates in peas by adult cockerels.

The digestion of starch and fibre by adult cockerels fed peas which were whole, ground, autoclaved, heated, dehulled, cooked or supplemented with a cellulose degrading enzyme was studied. The starch in ground peas that had been autoclaved, heated or dehulled was slightly, though not significantly, better digested than the starch in peas that had been ground only. Feeding peas whole greatly reduced starch digestibility. Cooking failed to improve starch digestibility as retrograded starch produced in the cooking process was not digested. The more finely ground the foodstuff, the better the in vitro enzymatic hydrolysis of starch. Starch digestibility correlated well (r2 = 0.80) with the true metabolisable energy values obtained for the different pea treatments. In experiment 1 cockerels digested on average 0.22 of the pea fibre from the different forms of peas. A significant decrease in xylose digestion was observed when birds were fed dehulled peas, birds excreting more xylose than they ingested. In experiment 2, cockerels digested on average 0.38 of the pea fibre from different forms of peas. A reduction in fibre digestion was observed when birds were fed cooked peas as a consequence of a decreased digestibility of all monosaccharide residues. A slight increase in fibre digestion was observed when peas were augmented with 'cellulase', entirely because of an increase in xylose digestion.

Nutritive Value of High Oil Corn for Poultry

Several experiments were conducted to evaluate the nutritional value of high oil corn for poultry relative to that of conventional (CONV) corn. The variety of high oil corn (HO1) evaluated in most trials contained 6.0% oil and 9.6% protein on a 10% moisture basis. The protein quality of HO1 and CONV corn was assessed with female crossbred chicks fed corn as the sole source of dietary protein. There was no difference in either protein efficiency ratio or in net protein ratio between the two types of corn. True metabolizable energy (TME) and nitrogen-corrected TME (TMEn) values of HO1 corn were determined using adult roosters. The TME and TMEn values of HO1 corn were approximately 4.5% higher than those of CONV corn.Two experiments were conducted to evaluate the use of high oil corn varieties, containing from 6 to 13% oil, in practical diets of commercial broiler chicks from 8 to 22 days posthatching. Weight gain, gain-to-feed ratio, and skin and plasma pigmentation were improved in chicks fed 24% protein diets containing high oil corns compared with those fed the same diet containing CONV corn; magnitude of response was highly correlated to oil content of the corn.The relative value of HO1 corn in practical laying hen diets was examined in a 15-wk experiment. Hens fed a 17% protein diet containing HO1 corn from 23 to 38 weeks of age had a better feed-to-egg ratio than those fed the same diet containing CONV corn when the corn sources were substituted on an isonitrogenous basis. There were no significant differences between corn types for other production parameters, although egg production and egg yield tended to be improved (P<.10) for hens fed the 17% protein diet containing HO1 corn.

Animal Fat Effects on Nutrient Utilization

Laying hens were employed to study the effects of carrier on the true metabolizable energy (TME) of tallow using corn, milo, soybean meal, wheat bran, and dehydrated alfalfa meal with tallow at 0, 2, 4, or 6%. In addition to bomb calorimetry measurements on feed and excreta samples, tallow TME values were calculated from absorbability data.Estimates of TME for tallow varied with carrier feedstuff from 7.19 kcal/g in soybean meal to 13.62 kcal/g when wheat bran was fed. For the corn, milo, and soybean meal series only fat retentions were significantly affected by tallow supplementation. Calculated tallow absorbabilities were 101.8% with corn, 95.8% with milo, and 107.3% with soybean meal. Highest tallow TME values were obtained with wheat bran and dehydrated alfalfa meal, apparently due to increased protein retention from wheat bran and to both improved protein retention and starch absorption with dehydrated alfalfa meal.

Influence of site and variety on starch, hemicellulose and cellulose composition of wheats and their digestibilities by adult cockerels

Abstract 1. It has been shown that both the variety of wheat and the environment under which growth took place influenced the quantities of starch and cell wall carbohydrate contents of wheat. 2. The different varieties of wheat investigated contained different proportions of water‐soluble to water‐insoluble hemicelluloses. 3. By comparison of the arabinose to xylose ratios it was concluded that water‐soluble and insoluble arabinoxylans of wheat were branched to the same degree. 4. Starch from six wheat varieties grown in the U.K. was very well digested by adult cockerels and true metabolisable energy values of the wheats were high. 5. Small amounts of cell wall carbohydrates were digested by adult cockerels.

Repeatability of True Metabolizable Energy Versus Nitrogen Corrected True Metabolizable Energy Values

Abstract Comparisons were made between the repeatability of true metabolizable energy (TME) and nitrogen corrected TME (TMEn) values for yellow corn and dehulled soybean meal (SBM). Seven samples of each ingredient were evaluated twice for TME and TMEn content. The mean differences between the two determined TME and TMEn values (i.e., repeatability) were 1.2 and .5%, respectively, for corn and 2.6 and 2.7% for SBM. It is concluded that both TME and TMEn values are highly reproducible.

Methane Digester Effluent as a Feedstuff for Layers

Abstract Methane digester effluent (MDE) from a full-scale digester (FD) was studied as a potential wet feedstuff for caged layers. Hens fed corn-soybean meal diets meeting National Research Council (NRC, 1977) nutrient requirements and containing up to .5% MDE, dry matter (DM) basis, showed no significant difference in hen-day egg production when compared with controls. Higher MDE levels (1.0 to 2.6%) produced a significant reduction in egg production. Egg weight and specific gravity were not affected by level of MDE. Haugh unit was adversely affected only in eggs laid by hens fed the highest level of MDE. True metabolizable energy (TME) and nitrogen corrected true metabolizable energy (TMEn) values of MDE samples from two types of digesters, pilot (PD) and full-scale were determined. Dry matter content was 2.92 and 1.58% for PD and FD, respectively. Mean gross energy values were 3502 and 3792 kcal/kg, and mean TME values were 1076 and 692 kcal/kg for PD and FD, respectively (dry matter basis). Both MDE samples had high gross energy values but comparatively low TME values, indicating that a large part of the nutrients in MDE were not digestible. The TMEn values were 936 and 531 kcal/kg for PD and FD, respectively. Based on this study, .5% full-scale MDE (DM basis) is suggested as the maximum level that should be used in a caged layer diet.

A Methodological Study of the Relationship Between the Metabolizable Energy-Values of Two Meat Meals and Their Level of Inclusion in the Diet

The nitrogen-corrected apparent (AMEn) and true (TMEn) metabolizable energy values of a low-fat and a high-fat meat meal (MM) were studied. Adult roosters were fed ad libitum on a basal diet or a mixture of the basal diet and one of the two MM. At up to 60% incorporation, MM were introduced at the expense of corn in the basal diet. Dietary inclusion was at 5, 10, 20, 40, and 60%; birds were also force-fed pure MM. The ME of MM decreased as MM content in the diet increased. Highest AMEn were observed when the MM was 5% of the diet (3356 and 1715 kcal/kg for the high- and low-fat MM, respectively); this may have been attributable to synergism of MM and basal diet fatty acids. The lower ME observed with higher MM could result from interactions between calcium and one or both fatty acids and proteins. It is concluded that ME of MM should be measured in diets containing low practical MM. Artificially high experimental levels of 50 or 100% may lead to underestimation of the energy of MM.