True Ileal Digestibility Coefficients Research Articles

129 Effect of Ronozyme® WX supplementation on apparent and true ileal amino acid digestibility coefficients in broiler chicks fed varying levels of rice bran

Abstract An experiment was conducted to investigate the effect of rice bran (RB) and Ronozyme® WX on apparent and true ileal amino acid (AA) digestibility coefficients in broiler chicks using a regression approach. Two hundred and forty 21-day-old Abor Acre plus chicks were randomly allotted to six diets with varying levels of RB (100, 200 and 300 g/kg) without (0g/kg) or with Ronozyme® WX (25g/kg) supplementation in a 2x3 factorial arrangement using a randomized complete block design. Each treatment had 5 replicates with 8 birds each. The birds were fed for 5 days (d 22–26). On d 26, digesta was sampled from distal ileum. Data were analyzed using general linear model at α0.05. Lysine had the highest concentration among the essential amino acids (AAs) while the lowest concentration was observed for threonine. Rice bran at 10% for the essential amino acids with enzyme was significantly higher but compared with concentrations of RB at 10% and 20% without enzyme. There were no significant differences among the true ileal amino acid digestibility coefficients except lysine (10% RB) without enzyme (0.91) which was significantly higher than 20% RB with enzyme (0.84) but similar to other treatments. Rice bran with enzyme had a significant (P < 0.05) interactive effect on the apparent ileal digestibility coefficients of arginine, histidine, isoleucine methionine and phenylalanine. When RB was supplemented with enzyme, a significant (P < 0.05) interactive effect on true ileal digestibility coefficients of arginine and methionine was observed. Rice bran-enzyme interaction had no significant effect on the non-essential AAs. The slopes of the regression lines ranged from 0.77 (arginine) to 0.98 (phenylalanine). In conclusion, enzyme supplementation did not significantly influence the digestibility coefficients of AA in rice bran. However, the inclusion of 10% and 20% RB supplemented with Ronozyme® can help to improve the methionine content in rice bran.

Amino acid digestibility of larval meal (Musca domestica) for broiler chickens

Work was undertaken to investigate the potential use of housefly (Musca domestica) larvae reared on broiler manure as a source of nutrition for poultry production in the United Kingdom. Nutritional analysis showed that larvae have a high (>45% dry wt.) protein content and a favorable amino acid profile that is rich in key amino acids, such as lysine and methionine. A broiler digestibility trial was carried out to determine the apparent ileal digestibility coefficients (AIDC) and true ileal digestibility coefficients (TIDC) of amino acids (AA) from insect larval meal (ILM) from M. domestica and fishmeal (FM) in broiler chickens. This was calculated using multiple linear regression technique based upon 3 inclusions of each protein source in a semisynthetic diet. One-hundred-forty-four day-old male (Ross 308) broilers were fed from hatch on a commercial starter diet for 20 days. Experimental diets were fed from d 21 to 28, and feed intakes were measured daily. On d 28, the trial was terminated, ileal digesta were collected for the determination of AIDC and TIDC of AA, and inflammatory responses (gizzard erosion and eye discharge) were measured. No significant differences were observed in digestibilities between protein sources for any AA. Furthermore, ILM feeding did not induce gizzard erosion or eye discharge at any inclusion. These results provide strong evidence to suggest that ILM of the common housefly can provide a successful alternative protein source to FM in broiler diets.

Effect of the addition of β-mannanase on the performance, metabolizable energy, amino acid digestibility coefficients, and immune functions of broilers fed different nutritional levels

Three experiments were conducted to evaluate the effect of β-mannanase (BM) supplementation on the performance, metabolizable energy, amino acid digestibility, and immune function of broilers. A total of 1,600 broilers were randomly distributed in a 4 × 2 factorial arrangement (4 nutritional levels × 0 or 500 g/ton BM), with 10 replicates and 20 broilers per pen. The same design was used in the energy and digestibility experiments with 8 and 6 replicates, respectively, and 6 broilers per pen. The nutritional levels (NL) were formulated to meet the nutritional requirements of broilers (NL1); reductions of 100 kcal metabolizable energy (NL2); 3% of the total amino acids (NL3); and 100 kcal metabolizable energy and 3% total amino acids (NL4) from NL1. The serum immunoglobulin (Ig) concentration was determined in two broilers per pen, and these broilers were slaughtered to determine the relative weight of spleen, thymus, and bursa of Fabricius. Throughout the experiment, the lower nutritional levels reduced (P < 0.05) body weight gain (BWG) and increased (P < 0.05) feed conversion (FCR) for the NL4 treatment. The BM increased (P < 0.05) the BWG values and improved (P < 0.05) the FCR of the broilers. The apparent metabolizable energy corrected for nitrogen balance (AMEn) values were reduced (P < 0.05) for NL2 and NL3. The BM increased (P < 0.05) the AMEn values and reduced (P < 0.05) the excreted nitrogen. NL3 and NL4 reduced (P < 0.05) the true ileal digestibility coefficients (TIDc) of the amino acids cystine and glycine, and BM increased (P < 0.05) the TIDc for all amino acids. The addition of BM reduced (P < 0.05) the relative weights of the spleen and bursa. NL2 increased (P < 0.05) the Ig values, whereas BM reduced (P < 0.05) the serum IgA, IgG, and IgM values of the broilers. This study indicates that using suboptimal nutrient levels leads to losses in production parameters, whereas BM-supplemented diets were effective in improving performance, energy values, and TIDc levels of amino acids and immune response of broilers.

Measurement of true ileal calcium digestibility in meat and bone meal for broiler chickens

The objective of the present experiment was to determine the true ileal calcium (Ca) digestibility in three samples of meat and bone meal (coded as MBM-1, MBM-2 and MBM-3) for broiler chickens. Four experimental diets, containing graded concentrations of Ca, were formulated from each MBM sample with inclusion levels of 20, 40, 60 and 80g/kg diet. Each experimental diet was randomly allotted to four replicate cages (six birds per cage) and fed for three days from day 28 post-hatch. Apparent ileal digestibility coefficient of Ca was measured by the indicator method and linear regression analysis was used to determine the true Ca digestibility coefficient. Apparent Ca digestibility was unaffected (P>0.05) by increasing Ca concentrations. The apparent digestibility coefficients in MBM-1, MBM-2 and MBM-3 were 0.50, 0.44 and 0.45, respectively. Significant linear (P<0.001) relationship was observed between dietary Ca intake and digesta Ca output for MBM-1, MBM-2 and MBM-3 with R2 values of 0.82, 0.93 and 0.95, respectively. The true ileal digestibility coefficients of Ca in MBM-1, MBM-2 and MBM-3 were determined to be 0.60, 0.46 and 0.50, respectively. The corresponding ileal endogenous Ca losses were 292, 123 and 174mg/kg dry matter intake, respectively.

Corns with Different Nutritional Profiles on Growing and Finishing Pigs Feeding (30 to 90 kg)

Three experiments were carried out to determine the nutritional value and to verify the pig performance in growing and finishing phases (30 to 90 kg) fed on diets containing common corn (CC), high-lysine corn (HLC) and high-oil corn (HOC). In the total digestibility trial (Exp. I) 12 barrows were used. Values of digestible energy (DE) and metabolizable energy (ME) as-fed basis for CC, HLC and HOC, were: 3,396 and 3,275 kcal/kg; 3,248 and 3,139 kcal/kg; 3,445 and 3,308 kcal/kg, respectively. In order to determine the apparent and true ileal digestibility coefficients of amino acids, as well as the values of true digestible amino acids of the CC, HLC and HOC, an ileal digestibility trial was done (Exp. II) with T-cannulated barrows (T simple). The treatments consisted of three diets, with one of them as the sole source of protein (CC, HLC and HOC). In the performance experiment (Exp. III), 36 crossbred pigs, allotted in a completely randomized design with three treatments and 12 replications were used. Treatments consisted of three diets: 1 - CC; 2 - HLC and 3 - HOC. It was observed no difference for performance and carcass variables among the corns with different nutritional profiles. Results of the three experiments highlighted the importance of segregating corns in their real chemical and energetic composition as well

Determinação das perdas endógenas e da digestibilidade ileal da proteína e dos aminoácidos em suínos utilizando-se duas técnicas

Objetivou-se neste estudo determinar os coeficientes de digestibilidade ileal verdadeira da proteína e dos aminoácidos digestíveis de um extrato protéico de levedura utilizando-se duas técnicas - dieta isenta de proteína (DIP) e dieta com caseína hidrolisada enzimaticamente (CHE) - para determinação das perdas endógenas de proteína, aminoácidos e nitrogênio. Foram utilizados 12 suínos mestiços, machos castrados, com peso médio de 35 kg, submetidos previamente a cirurgia para implantação da cânula T simples. O delineamento experimental foi o inteiramente casualizado com três tratamentos (dieta com CHE; dieta isenta de proteína (DIP); e dieta com 23% do extrato protéico de levedura - ingrediente teste), quatro repetições e um animal por unidade experimental. As perdas endógenas de ácido glutâmico, ácido aspártico, lisina, arginina e serina diferiram entre as dietas; os maiores valores foram obtidos nos animais que receberam a dieta com CHE. O maior valor de perda endógena do aminoácido glicina foi determinado nos animais alimentados com a dieta DIP. Os coeficientes de digestibilidade ileal verdadeira de metionina, treonina, triptofano e serina determinados pelas perdas endógenas utilizando-se a dieta CHE foram superiores àqueles determinados utilizando a dieta DIP. As quantidades das secreções protéicas e de aminoácidos obtidas pela técnica da CHE foram maiores que as determinadas pela técnica da DIP. Os coeficientes de digestibilidade verdadeira da proteína foram menores e os dos aminoácidos, maiores, quando determinados pela técnica CHE.

Digestibilidade ileal e perdas endógenas de aminoácidos de dietas com óleo de soja para suínos em crescimento

Este trabalho foi conduzido para avaliar o efeito de diferentes níveis de óleo de soja sobre as perdas endógenas e a digestibilidade ileal aparente e verdadeira dos aminoácidos em dietas para suínos em crescimento. Foram testadas quatro dietas isoprotéicas, à base de milho e farelo de soja, formuladas segundo as exigências para essa fase e suplementadas com níveis crescentes de óleo de soja (0,0; 1,5; 3,0; 4,5%) e 0,25% de óxido crômico como indicador de indigestibilidade. Dezesseis suínos canulados (cânula T simples), com 48,0 ± 6,0 kg, foram distribuídos em um delineamento em blocos casualizados, com base no peso dos animais. Não houve efeito dos níveis óleo de soja sobre os coeficientes de digestibilidade ileal aparente de glutamato, glicina, arginina, alanina, prolina, tirosina, histidina e lisina. Observaram-se efeito linear da suplementação com níveis de óleo de soja nos coeficientes de digestibilidade ileal aparente e verdadeira de serina e treonina e efeito quadrático da suplementação de óleo de soja sobre os coeficientes de digestibilidade ileal aparente e verdadeira de valina, fenilalanina, total de aminoácidos não-essenciais e total de aminoácidos essenciais. Os coeficientes de digestibilidade ileal verdadeira de arginina e tirosina também apresentaram efeito quadrático da suplementação de óleo de soja. Melhores valores de digestibilidade ileal aparente e verdadeira dos aminoácidos não-essenciais e essenciais são obtidos com adição de 2,8 a 3,0% de óleo de soja à dieta de suínos em crescimento.

Amino acid digestibility and nitrogen utilization of high oil, high lysine, and waxy maize fed to growing pigs

Two experiments were conducted to determine the amino acid (AA) digestibility and nitrogen (N) utilization of three maize hybrids, i.e. high oil (HO), waxy (WX), and high lysine (HL) as compared to isogenic high oil (IHO), isogenic waxy (IWX), and a yellow dent (YD1) maize variety near-isogenic to HL. One yellow dent maize of unrelated genetics (YD2) was included as an additional control and to serve as a common treatment for cross-square comparison. In exp. 1, four castrates (initial BW: 52.8±1.7 kg) were equipped with T-cannulas in the distal ileum and used in two consecutive 4×4 Latin squares to determine AA digestibility. In exp. 2, eight castrates (initial BW: 19.11±0.49 kg) were arranged in two 4×4 Latin squares and used in a N balance experiment. Diets consisted of 966.2 g test maize/kg and 33.8 g vitamins, minerals, and salt/kg. In exp.1, apparent ileal digestibility coefficients (CAID) for HO and WX were not different ( P>0.05) compared to their respective isogenic maize or YD2. High lysine maize had lower ( P<0.05) CAID for isoleucine, leucine, methionine, phenylalanine, threonine, and valine when compared to YD1, its near-isogenic maize, and lower ( P<0.05) CAID for isoleucine, leucine, and phenylalanine when compared to YD2. Mean CAID for HO, WX, HL, and YD2 were 0.65±0.05, 0.70±0.05, 0.53±0.05, and 0.60±0.03, respectively. True ileal digestibility coefficients (CTID) for the indispensable AA did not differ when HO and WX maize were compared to their respective isogenic maize, but HL maize had lower ( P<0.05) CTID for the majority of indispensable AA except for arginine and histidine than YD1. Mean CTID for HO, WX, HL, and YD2 were 0.78±0.04, 0.84±0.04, 0.67±0.04, and 0.77±0.03, respectively. Nitrogen retained, urinary N, fecal N, N digestibility, and N utilization for HO, WX, and HL were not different ( P>0.05) compared to their genetically similar maize. Nitrogen absorbed and DM digestibility were higher ( P<0.05) for HO than for IHO. Nitrogen digestibility was similar ( P>0.05) for WX compared to YD 2 and greater ( P>0.05) for HO and HL compared to YD 2. In conclusion, AA CAID and CTID, were similar for HO and WX maize compared to their isogenic maize, however, AA CAID and CTID for HL maize was lower than its near-isogenic maize. Nitrogen utilization for HO, WX, and HL were similar to that of their respective genetically similar maize.

Comparison of methods to determine the endogenous amino acid flow at the terminal ileum of the growing rat

AbstractThe aim was to compare a recently developed peptide alimentation method and the protein‐free and regression methods for determining endogenous ileal nitrogen (N) and amino acid excretion in the rat, and to apply the endogenous loss estimates to determine the true ileal digestibility of a meat and bone meal (MBM). Preliminary investigations determined the effect of the time of sampling of digesta after a meal (slaughter method) for rats given a protein‐free or an enzymically hydrolysed casein (EHC) based diet, on ileal digesta and endogenous N excretion. There was a significant (P &lt; 0.05) effect of the time of sampling on the amount of digesta collected and the endogenous N excretion for both the EHC and protein‐free fed rats. The amount of digesta collected from the terminal 20 cm of ileum and the endogenous N excretion for both the EHC and protein‐free fed rats were greatest and least variable at 3 h post‐feeding. In the main study, endogenous ileal amino acid excretions were determined in the growing rat fed an EHC‐based diet (n = 6) and with subsequent treatment of the digesta using ultrafiltration or in six rats given a protein‐free diet or by extrapolation from data for 30 animals given five diets which contained graded levels of MBM as the sole protein source. For the EHC treatment, the ileal digesta precipitate plus retentate was used to determine the endogenous flows. The ultrafiltration step excludes unabsorbed dietary amino acids from the measure of endogenous loss. Chromic oxide was the reference marker in all diets. The endogenous N flows determined by the protein‐free and regression methods were similar but both significantly (P &lt; 0.01) lower than those for rats fed the EHC‐based diet. The mean endogenous ileal N flows determined by the peptide alimentation method, the protein‐free and regression approaches were 1866, 1103 and 1019 μg g−1 freeze dry matter intake, respectively. The endogenous amino acid flows at the terminal ileum were lower when determined using the traditional protein‐free or regression methods. The true ileal digestibility coefficients for MBM were considerably higher based on the EHC versus protein‐free endogenous flows.

Endogenous lysine flow at the distal ileum of the protein‐fed rat: Investigation of the effect of protein source using radioactively labelled acetylated lysine or lysine transformed to homoarginine

AbstractThe study aimed to determine if the source of purified dietary protein influenced endogenous lysine flow at the terminal ileum of the growing rat. Partially guanidinated gelatin and isolated soya bean protein based diets, containing chromic oxide as an indigestible marker, were given to 225‐g liveweight rats. The endogenous flow of lysine at the terminal ileum was then determined indirectly, based on the absorption of homoarginine, after sampling of ileal contents at slaughter. Endogenous lysine flow was also determined by reference to chromium levels in sampled ileal digesta, after feeding rats either gelatin or isolated soya bean protein or casein based diets in which some of the lysine had been acetylated with [14C]‐acetic anhydride. The [14C] acetylated lysine was used to distinguish between lysine of dietary and endogenous origin. Mean endogenous ileal lysine flows were 426 and 442 μ g−1 dietary freeze dry matter intake for the guanidinated gelatin (n=6) and soya bean (n = 6) treatments, respectively, and there was no significant (P&gt;0.05) effect of protein source on endogenous flow. Nor did there appear to be any effect of dietary protein source on endogenous ileal lysine flow when measurement was based on the radio‐actively labelled acetylated lysine. The data, considered together, indicate no effect of the source of dietary protein per se on endogenous ileal lysine flow in the rat when purified proteins were given over a short (8‐h) time period. The mean true ileal digestibility coefficients for dietary lysine (0.897, 0.904, 0.926, 0.971, 0.916; acetylated gelatin, guanidinated gelatin, guanidinated soya bean, acetylated soya bean, acetylated casein, respectively) indicated a high degree of absorption of lysine before the end of the ileum in the growing rat.