TMEn Content Research Articles

Impact of Extended Heat Treatment on the Amino Acid Digestibility and TMEn Content of a Formaldehyde-Treated Diet

SUMMARY Eliminating the contamination of broiler carcasses by pathogens such as Salmonella that can cause human illness continues to be a tremendous challenge and concern for the poultry industry and government regulatory agencies. One source for the introduction of these pathogens in poultry production can be the feed. Extended heat conditioning of diets prior to pelleting combined with the addition of preservatives such as formaldehyde has proven effective in reducing the risk of Salmonella in poultry diets. However, there has been a concern that the addition of some forms of formaldehyde to diets subjected to extended heat treatment could decrease the metabolizable energy and amino acid availability of the diet. To partially address this question, the TMEn and digestible amino acid coefficients of a broiler starter diet treated with 0 (control) or 0.3% formaldehyde solution prior to heat treatment at 82°C for 4.5 min were determined. Cecectomized and intact adult Single Comb White Leghorn roosters were used for determining amino acid digestibility and TMEn, respectively. The addition of the formaldehyde compound did not affect either the TMEn or the digestible amino acid content of the diet, except for a marginal (less than 1%) decrease in arginine digestibility. These results indicate that the supplementation of poultry diets with formaldehyde solution prior to extended heat treatment to eliminate Salmonella contamination did not impact the nutritional value of these diets for poultry.

Using complete diet and Sibbald methods to determine the metabolizable energy of 5 Iranian wheat varieties

SUMMARY To determine the ME contents of 5 Iranian wheat varieties (Alvand, Zarrin, Sabalan, Sardari, and Azar2), 2 experiments were conducted. In experiment 1, the AMEn content of 5 wheat varieties was determined by complete diet method containing 62.06% of a test cereal grain (with or without an appropriate commercial enzyme). Diets were consumed ad libitum by sixty 21-d-old Ross 308 male broiler chicks. The AMEn values (kilocalories per kilogram of cereal grain, DM basis) were determined from gross energy of diet and collected excreta during 56 h at the end of the experiment. In experiment 2, 36 adult roosters were used to determine the TMEn content of the varieties by the precision feeding method. The AMEn content was not significantly affected by varieties. The AMEn of wheat varieties without enzyme supplementation varied from 3,120 to 3,191 kcal/kg. The AMEn was significantly affected by enzyme supplementation. Enzyme addition produced an average increase of 11.45% AMEn content of wheat varieties. The TMEn of wheat varieties varied from 3,788 (Sabalan variety) to 3,947 kcal/kg (Zarrin variety), and TMEn content was affected significantly by wheat varieties. Strong correlation was seen between broiler chick performance and AMEn of wheat varieties that determinate with the complete diet method in wheat-based diets. It is suggested that the AMEn obtained from the complete diet method should be applied in young broiler diets formulation.

Estimation and modeling true metabolizable energy of sorghum grain for poultry

Sorghum grain is an important ingredient in poultry diets. The TMEn content of sorghum grain is a measure of its quality. As for the other feed ingredients, the biological procedure used to determine the TMEn value of sorghum grain is costly and time consuming. Therefore, it is necessary to find an alternative method to accurately estimate the TMEn content. In this study, 2 methods of regression and artificial neural network (ANN) were developed to describe the TMEn value of sorghum grain based on chemical composition of ash, crude fiber, CP, ether extract, and total phenols. A total of 144 sorghum samples were used to determine chemical composition and TMEn content using chemical analyses and bioassay technique, respectively. The values were consequently subjected to regression and ANN analysis. The fitness of the models was tested using R2 values, MS error, and bias. The developed regression and ANN models could accurately predict the TMEn of sorghum samples from their chemical composition. The goodness of fit in terms of R2 values corresponding to testing and training of the ANN model showed a higher accuracy of prediction than the equation established by regression method. In terms of MS error, the ANN model showed lower residuals distribution than the regression model. The results suggest that the ANN model may be used to accurately estimate the TMEn value of sorghum grain from its corresponding chemical composition.

Nutrient composition of different varieties of full-fat canola seed and nitrogen-corrected true metabolizable energy of full-fat canola seed with or without enzyme addition and thermal processing

SUMMARY Samples of 3 varieties of full-fat canola seed (FFCS), Okapi, Opera, and SLM046, were obtained from a local oilseed company, and chemical composition and mineral content of the 3 varieties were determined. Crude protein content of the canola seed ranged from 19.5 to 21.4%, with an average of 20.36 ± 0.85%. Ether extract of the canola seed ranged from 47.3 to 50.4%, with an average of 48.77 ± 0.92%. Composition of the main fatty acids in the oil was determined by gas chromatography. The saturated fatty acid content of Okapi and SLM046 (including palmitic and stearic acids) was very low compared with the unsaturated fatty acid content, and oleic acid (C18:1n-9 cis) constituted the highest proportion of fatty acids (52.56%) in SLM046 (with an average content of 35.84%). Canola seed is rich in C18:3n-3 fatty acids, and the oil of canola seed is an excellent source of α-linolenic acid (8 to 12%). The calcium content of Okapi, Opera, and SLM046 was 1.05, 0.97, and 0.7%, respectively. The average Mg content of canola seed was 0.14 ± 0.007%. Iron content ranged from 45.2 to 51.7 mg/kg in the 3 varieties of FFCS. Zinc content of Okapi, Opera, and SLM046 was 11.1, 17.6, and 13.7 mg/ kg, respectively. Mean content of Mn was 35.57 ± 0.57 mg/kg, and that of Cu was 11.97 ± 0.42 mg/kg in the FFCS samples. The effects of variety, enzyme addition, and thermal processing on the ME of ground FFCS were investigated in a TMEn assay with adult roosters. Ground FFCS samples were heated at 120°C for approximately 3 h in an electric oven. A currently available commercial multienzyme was added to the 3 raw varieties of FFCS at an inclusion level of 0.5%. The average TMEn content of ground FFCS was 5,495 kcal/kg, and a significant difference was found between the 3 varieties of canola seed (P < 0.05). The TMEn content of ground FFCS was not affected by thermal processing or multienzyme supplementation.

Evaluation of Illinois Bundleflower (Desmanthus illinoensis) for Broiler Chicks

Illinois bundleflower (IBF; Desmanthus illinoensis) is a warm-season perennial legume native to the central plains of the United States and has potential as both a forage and grain crop. The objective of this research was to evaluate the potential of IBF seeds as a feed ingredient in broiler starter diets. One-day-old broiler chicks were fed 1 of 4 isocaloric and isonitrogenous experimental diets containing 0, 5, 10, or 15% IBF seed. Illinois Bundleflower seed is a high-protein (31.5% CP) feed ingredient with a Lys:Met similar to that of soybean meal. The TME content of IBF seed depends on the form in which it is fed. When fed ground, the TMEn content was determined to be 1,974 kcal/kg. When fed whole, with supplemental grit, the TMEn content was 1,067 kcal/kg. Inclusion of IBF seed in broiler starter diets had adverse affects on both feed consumption and BW gain, even at a 5% inclusion level. Further studies are required to determine whether IBF seed could be included in diets for older broiler chicks or laying hens.

Effect of Soaking in Water and Rumen Digeta Solutions on Metabolizable Energy Content and Chemical Composition of Barley Seeds for Use in Poultry Diet

An experiment was carried out to evaluate the effect of soaking in water and different rumen digesta solutions on nutritional value of dry barley seeds. Treatments were included distilled water as control and rumen digesta that diluted with distilled water to obtain 20, 40 and 60% digesta solutions. Solutions have added to 10 kg of barley seed samples to achieve final 30% moisture content. After 21 days the chemical composition and energy content of barley seed were determined. Gross energy of barley seeds did not affected by different experimental treatments. Use of 20% rumen digesta solution resulted to a significant (p<0.01) increase in AME and AMEn content of barley seeds. Barley seed that treated with 40% of rumen digesta solution had highest TME and TMEn content and its different from seeds that treated with 60 and 100% rumen digesta solutions was significant (p<0.05). The chemical composition such as dry matter, crud protein, crude fat, crud fiber, ash and NFE were found to be similar and there was no significant difference. However, soaking in rumen digesta solutions increased crud protein, ether extract, crude fiber and ash content of barley seeds numerically.

Amino acid availability and true metabolizable energy content of corn distillers dried grains with solubles in adult cecectomized roosters

Five sources of corn distillers dried grains with solubles (DDGS), which varied in darkness of color, were collected from several processing plants in the Midwestern United States. Sources of DDGS were analyzed for their amino acid and energy contents, measured for color score, and evaluated for TMEn, apparent amino acid digestibility, and true amino acid digestibility. A precision-fed rooster assay was used, in which each DDGS sample was tube fed (25 g) to adult cecectomized roosters, and the excreta were collected for 48 h. The experiment was conducted as a randomized complete block design with 8 replicates. Seven adult roosters (averaging 75 wk of age) were used in each period, with 5 fed the DDGS sources and 2 fasted to estimate basal endogenous amino acid losses. One source (no. 5) was the darkest, 2 sources (no. 2 and 4) were light, whereas 2 other sources (no. 1 and 3) were intermediate in color as measured by a colorimeter. Total lysine content of the DDGS sources ranged from 0.48 to 0.76%, with the lowest lysine content in the darkest DDGS source. Apparent and true lysine digestibility was approximately 30 and 15 percentage units lower (P < 0.05), respectively, in the dark-colored source (no. 5) than in the other 4 sources. Average apparent and true digestibility of the essential amino acids were 10 and 8 percentage units lower (P < 0.05), respectively, in source 5 than the other 4 sources. The TMEn content of the 5 DDGS sources was also lower (P < 0.05) in the darkest DDGS (no. 5). Our results suggest that when the color score of a DDGS source, as measured by a colorimeter, reached a certain threshold (lightness between 28 and 34), amino acid availability and true metabolizable energy content may be reduced. This reduction was particularly evident for lysine, which had the lowest digestibility in the darkest DDGS source. These results suggest that dark-colored DDGS may have been overheated during drying, causing Maillard reactions to be more extensive and resulting in a lowered total lysine content, lysine digestibility, and TMEn content.

The Use of Enzyme Technology for Improved Energy Utilization from Full-Fat Oilseeds. Part II: Flaxseed

An in vitro incubation study was carried out to determine whether various carbohydrase preparations contained appropriate activities to target nonstarch polysaccharides (NSP) of full-fat flaxseed. Enzyme preparations C (cellulase, 340 U/g), XG (xylanase, 63,600 U/g and glucanase, 48,300 U/g), P (pectinase, 10,000 U/g), and MC (mannanase, 10,900 U/g and cellulase, 600 U/ g), alone and in combination (C + P, C + XG, P + XG, C + P + XG, C + P + MC, and C + P + XG + MC), were evaluated. Triplicate samples of defatted flaxseed meal (0.1 g) were incubated with 1% single enzymes or combinations at 45 ° C and pH 5.2. A more pronounced degradation of NSP was achieved when the enzyme preparations were used in concert. Compared with the control (no enzyme) treatment, the degree of NSP degradation averaged 34.7% when the sample was incubated with the 3 most effective enzyme combinations (C + P + XG, C + P + MC, and C + P + XG + MC). The effect of carbohydrase enzyme supplementation on energy utilization from full-fat flaxseed was investigated in a TMEn assay with adult roosters. When compared with the nonsupplemented sample, an increase (P < 0.05) in TMEn content from 2,717 to 3,751 kcal/kg (on average) was observed for the flaxseed supplemented with enzymes C + P + XG, C + P + MC, and C + P + XG + MC. A similar pattern of increase (P < 0.05) in fat and NSP digestibilities was noted. Enzyme combination C + P + XG was further evaluated in a 2-wk (5- to 18-d) trial with broiler chickens fed a corn and soybean meal-based flaxseed (15%) diet or the flaxseed diet supplemented with the enzyme at 3 different levels: 0.002, 0.01, and 0.05%. When supplemented at the highest level, the enzyme blend improved (P < 0.05) feed:gain, total tract DM, fat and NSP digestibilities, AMEn content, and ileal fat digestibility. No effect of enzyme supplementation, regardless of the level used, on ileal protein digestibility and digesta viscosity was observed. The results of the current study suggest that multiactivity carbohydrase enzyme supplements may be used as a means to improve energy utilization from full-fat flaxseed and, thus, enhance its feeding value for poultry.

The Use of Enzyme Technology for Improved Energy Utilization from Full-Fat Oilseeds. Part I: Canola Seed

The effect of carbohydrase enzyme supplementation on energy utilization from full-fat canola seed was investigated in a TMEn assay with adult roosters and in a nutrient digestibility and growth performance study with broiler chickens. In the TMEn assay, enzyme preparations C (cellulase, 340 U/g), XG (xylanase, 63,600 U/g and glucanase, 48,300 U/g), P (pectinase, 10,000 U/g), and MC (mannanase, 10,900 U/g and cellulase, 600 U/ g), alone and in combination (C + P, C + XG, C + MC, P + XG, P + MC, XG + MC, C + P + XG, C + P + MC, and C + P + XG + MC), were evaluated at an inclusion level of 0.1%. On average, hammer-milled canola seed with a TMEn content of 3,642 kcal/kg showed an increase (P < 0.05) to 4,783 kcal/kg following supplementation with the enzyme blends C + P + XG, C + P + MC, and C + P + XG + MC. A similar pattern of increase (P < 0.05) in fat (80.4 vs. 63.5%) and nonstarch polysaccharide (NSP; 20.4 vs. 4.4%) digestibilities was observed. Enzyme combination C + P + XG was further evaluated in a 2-wk (5- to 18-d) trial with broiler chickens fed isonitrogenous and isoenergetic corn and soybean meal-based diets containing canola seed (15%), the corresponding canola meal (8.85%) plus canola oil (6.15%) mixture, or canola seed (15%) supplemented with 3 different levels (0.002, 0.01, or 0.05%) of the enzyme. Poorer (P < 0.05) feed:gain (1.412 vs. 1.344), lower (P < 0.05) total tract DM (65.9 vs. 70.7%) and fat (69.6 vs. 88.0%) digestibilities, lower AMEn content (2,963 vs. 3,200 kcal/kg), and lower ileal fat (65.6 vs. 85.6%) and protein (75.6 vs. 81.2%) digestibilities were observed for the canola seed diet compared with the canola meal plus canola oil diet. Enzyme supplementation of the canola seed diet resulted in an improvement (P < 0.05) in feed:gain; total tract DM, fat, and NSP digestibilities; AMEn content; and ileal fat digestibility. Although the enzyme effect on ileal and total tract fat digestibilities was significant at both high and medium inclusion levels, other parameters showed the significant improvement only when the highest inclusion rate of enzyme was used. These data support the need for carbohydrase enzyme supplements in poultry diets containing full-fat canola seed.

Utilization of spent hen meal in diets for broiler chickens

Studies were conducted to evaluate spent hen meal (SHM) produced in commercial rendering plants as a nutrient source in diets for broiler chickens. Utilizing previously determined nutrient composition values, including digestible amino acid and TMEn content, diets were formulated to include 0, 5, 10, and 15% of SHM from three different locations. In the first experiment, conducted in battery pens from 1 to 21 d posthatch, diets were formulated with digestible amino acid requirements set at 90, 95, or 100% of NRC (1994) total amino acid requirements. In the second experiment, conducted in floor pens from 1 to 49 d posthatch, diets were formulated with digestible amino acid requirements set at 95% of NRC (1994) total amino acid requirements. Samples of birds from the second experiment were processed to determine the possible influence of SHM inclusion on carcass yield. Results of the present studies indicate that SHM from commercial rendering facilities can be utilized in diets for growing broiler chickens provided adjustments are made in nutrient content and digestibility. When formulated on the basis of digestible amino acid content, levels of SHM up to 10% appear acceptable based upon body weight, feed conversion, bone ash, and carcass yield. Higher inclusion rates generally reduced performance. It is apparent that differences in nutritional quality may exist among products produced by different rendering facilities; however, evaluation of products to assess nutrient quality may be difficult under commercial conditions. As more information is generated regarding typical amino acid content and digestibility of rendered SHM, the product may be used with greater confidence in commercial diets.

The Effect of Enzyme Predigestion on the Quality of Poultry By-Product Meal from Whole Turkey Mortality

Enzyme predigested poultry by-product meal made from on-farm, whole turkey mortality (E-TBM) was compared with soybean meal (SBM) and commercial poultry by-product meal (CPBM) in each of three experiments. In Experiment 1, young poults were fed diets containing 16, 20, or 24% CP with either SBM or E-TBM as protein sources. A separate group of poults was fed a nitrogen-free diet. The E-TBM was higher than SBM in protein, fat, lysine, methionine, and total sulfur amino acids. Diets containing E-TBM resulted in increased BW, feed consumption, and a higher protein efficiency ratio (PER) and net protein ratio (NPR) compared with diets containing SBM. In Experiment 2, feeding nonenzyme-treated turkey by-product (TBM) or E-TBM resulted in significantly improved BW and feed efficiency compared with CPBM but this may have been due to decreased protein in diets containing CPBM. Protein source did not affect feed intake, PER, NPR, or net protein utilization (NPU). In Experiment 3, the TMEn content of CPBM was lower than both TBM and E-TBM but lysine and methionine digestibilities were greater.

Oligosaccharides in Canola Meal and Their Effect on Nonstarch Polysaccharide Digestibility and True Metabolizable Energy in Poultry

Balance studies utilizing laying hens and adult cockerels were conducted to determine the influence of oligosaccharides (raffinose and stachyose) present in canola meal (CM) on the digestibility of nonstarch polysaccharides (NSP) and on the TMEn of the meal. Ethanol extraction was used to produce oligosaccharide-free meal, and exogenous dietary enzymes (α-galactosidase and invertase) were employed to bring about oligosaccharide hydrolysis in the intestinal tract of the birds. In each of two balance trials, six hens individually housed were randomly allotted to each of the experimental diets in completely randomized design. Experiment 1 consisted of a factorial arrangement of treatments (two sources of protein with or without enzyme supplementation), whereas Experiment 2 consisted of five diets: semipurified CM control, semipurified ethanol-extracted CM; semipurified ethanol-extracted CM plus raffinose; conventional CM; and conventional ethanol-extracted CM. Elimination of oligosaccharides by the use of exogenous dietary enzymes had no effect on NSP digestion. Removal of oligosaccharides by ethanol extraction increased NSP digestibility from 4 to 8%. A more pronounced effect (17% NSP digestion) was noted in hens fed a wheat-based diet containing 30% oligosaccharide-free CM. This latter effect may have been due to the relatively high content of water-soluble polysaccharides contributed by the wheat portion of the diet. The TMEn content of ethanol-extracted CM was 2,302 kcal/kg as compared with 2,426 kcal/kg for untreated CM. The data indicate no advantage of oligosaccharide removal with regard to the nutritive worth of canola meal.

Research Note: An Evaluation of Soft and Hard Red Winter Wheat for Nitrogen-Corrected True Metabolizable Energy, Crude Protein, and Amino Acid Content

One study utilizing 8-wk-old Vantress × Arbor Acres male broilers was conducted to determine the TMEn, crude protein, and amino acid content of five soft and five hard composite red winter wheat cultivars from four farms. Soft cultivars evaluated included Caldwell, Pike, Arthur, Hart, and Delange, and the hard cultivars included Payne, Triumph, Tam 101, Chisholm, and Mustang. Energy availability as judged by TMEn, averaged over cultivar within the soft and hard classification, was similar (P > .10) at 3.30 and 3.32 kcal/g, respectively. Considerable variation existed among cultivars within classification, with Payne exhibiting the highest (3.6 kcal/g) and Delange the lowest (2.9 kcal/g) energy content. Average crude protein concentration was higher (P < .05) for the hard red winter wheat (16.0 versus 13.1%). Expressing amino acids as a percentage of crude protein yielded similar values for all amino acids except glutamic acid, methionine, and valine. Based on the data reported, it was confirmed that the hard red winter wheats contain more crude protein and proportionately more amino acids than the soft red winter wheat cultivars. Further, the data indicated that greater variability exists within rather than between the hard and soft red winter wheat categories for TMEn.

True Metabolizable Energy of Dried Bakery Product

Twenty-six samples of dried bakery product (DBP) were obtained from commercial sources and were evaluated for their proximate composition and TMEn content. Among the samples, marked variations were noted in ash, fiber, ether extract, and TMEn content. An equation to predict the TMEn content from the proximate composition was developed: TMEn (kcal/kg) = 3.9 + .02 × ether extract – .09 × crude fiber .03 × ash (R2 = .80).Ten additional samples of DBP were evaluated for proximate composition and TMEn in order to test the prediction equation. The error obtained when estimating the TMEn content from the prediction equation (4.1%) was substantially less than that obtained when assuming an average value based on Samples 1 to 36 (6.8%). The final prediction equation, derived from Samples 1 to 36, was: TMEn (kcal/g) = 4.34 –.10 × crude fiber – .04 × ash – .03 × protein + .01 × ether extract (R2 = .78).The mean errors based on the initial and final equations were 2.91 and 2.65%, respectively. Both compare favorably with the residual error of 5.78% obtained when using the average value of 3.63 kcal/g. All values given are expressed on the basis of 90% dry matter.

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.