Apparent Ileal Digestibility Of Nutrients Research Articles

Influence of different levels of black soldier fly larvae meal on growth performance and carcass quality of broiler chickens

A study was conducted to examine the impact of two inclusion levels of Black soldier fly larvae meal (BSFLM) replacing soybean meal on growth performance, nutrient utilization, carcass characteristics and meat quality of broilers. Three experimental diets based on corn-soybean meal were developed to contain 0 (control), 6 (BSF 6) and 12% (BSF 12) BSFLMfor both starter and grower phases. Each experimental diet was randomly allotted to six replicate pens (eight birds per pen). The birds were offered starter pellets from 0 to 14 day post-hatch and grower pellets from 15 to 28 day post-hatch. The experimental diets were tested for pellet durability index (PDI). There was an interaction between diet and growth phase (P < 0.001) for pellet durability index where starter diets had always a higher PDI than the grower diets, but the difference was greater for control diet than BSF 6 and BSF 12 diets. Apparent metabolizable energy (AME) of diets and coefficients of apparent ileal digestibility (CAID) of nutrients were measured on day 28 using titanium dioxide marker ratios in the diet and excreta/ileal digesta. On day 28, the weights of live body, carcass, fat pad, breast and gizzard were recorded, and then breast meat quality (meat pH, drip loss and cooking loss) was examined. Inclusion of BSFLM of up to 12 % did not reduce live weight gain or feed intake. Live weight and carcass weight were heavier in broilers fed 12 % BSFLM than controls (P < 0.02), but were not different than those fed 6 %, while controls were not different than those fed 6 %. Breast weight (percentage live weight) was lower in birds offered 12 % BSFL than in others (P < 0.04). No differences were observed between diets for the percentage weight as carcass, fat, pad and gizzard. The AME and AMEc of diets were the highest in broilers fed 6 % BSFLM diet (P < 0.005), but there were no differences between controls and those fed 12 % BSFLM. The CAID of DM, ash and N in birds fed 6 % BSFLM were greater than (P < 0.03) birds fed 12 %, but were not different than controls, which were also not different than those fed 12 %. Broiler breast meat quality was unaffected by dietary treatments. In conclusion, BSFLM at 12 % can be used effectively as a SBM replacement in starter and grower diets, without affecting the growth performance, nutrient utilization, carcass characteristics and meat quality of broiler chickens.

Response of YPM x Ross 708 male broilers to diets containing varying inclusions of phytase, calcium butyrate, and bacitracin methylene disalicylate from 1 to 42 d of age–part 1: performance, processing yields, and nutrient digestibility

This 42-d study evaluated the effects of phytase, calcium butyrate (CB), and bacitracin methylene disalicylate 50 (BMD) on broiler performance, processing yields, and nutrient digestibility. Ross YPM x 708 male broilers (2,880 total) were distributed in 72 floor pens and assigned to 1 of 9 treatments (8 replicates/treatment) on d of hatch. This experiment was a 2 × 4 + 1 factorial arrangement, including 2 phytase concentrations (500 or 1,500 FTU/kg), 4 microbiota modulating feed additive groups (MMFA; none, CB (0.5 g/kg of diet), BMD (55 mg/kg of diet), or both CB and BMD), and a negative control without feed additives. Broiler performance (d 14, 28, and 42), apparent ileal nutrient digestibility (d 28 and 42), and processing yields (d 43) were determined. Day 14 BW increased with BMD inclusion compared to CB and no MMFA in the 1,500 FTU/kg group but BW were similar between all MMFA combined with 500 FTU/kg (P ≤ 0.05). Supplementing BMD increased d 28 BW and reduced d 1 to 28 feed conversion ratio compared to CB and no MMFA (main effect, P ≤ 0.05). Day 42 BW varied depending on dietary phytase concentrations. When diets contained 500 FTU/kg, broilers fed both CB and BMD had a higher BW than broilers fed only CB. Whereas when the inclusion of phytase was increased to 1,500 FTU/kg, broilers fed diets with only BMD or both CB and BMD had higher BW than broilers fed diets with no MMFA (P ≤ 0.05). Phytase concentrations at 1,500 FTU/kg increased (P ≤ 0.05) digestibility of fat (main effect, d 42), phosphorus (d 28 and 42), and apparent ileal digestible energy (main effect, d 42) compared to 500 FTU/kg. In this study, dietary BMD improved broiler growth compared to CB and no MMFA. However, these observed differences between CB and BMD were dependent on dietary phytase concentrations.

Increasing digesta viscosity altered nutrient transporter gene expression and decreased nutrient utilisation in Eimeria-challenged birds

ABSTRACT 1. Two experiments were conducted, the first was to investigate the effect of increasing digesta viscosity by dietary carboxymethyl cellulose (CMC) on the growth performance and intestinal morphology and characteristics of healthy birds. The second experiment evaluated the impact of increased digesta viscosity in birds during an Eimeria spp. challenge. 2. In experiment 1, a corn-soybean meal-based basal diet was supplemented with 0, 10 or 20 g/kg CMC at the expense of cornstarch and offered to seven birds in each of eight replicate cages per diet from d 8 to 22 post hatching. 3. Increasing digesta viscosity due to dietary CMC linearly reduced (p < 0.05) body weight (BW) gain and the apparent ileal digestibility of nutrients. The relative lengths of the duodenum, jejunum and ileum linearly increased (p < 0.01) with dietary CMC inclusion. 4. In experiment 2, on d 14, 256 broiler chickens were randomly assigned to eight replicate cages in a 2 × 2 factorial arrangement of treatments with two CMC concentrations (0 or 10 g CMC/kg of diet), with or without an Eimeria challenge. On d 15, birds in the challenge groups were orally gavaged with a 1 ml solution containing 25,000, 25,000 or 125,000 oocysts of E. maxima, E. tenella and E. acervulina; or 1% PBS, respectively. 5. Increasing digesta viscosity in Eimeria-challenged birds decreased the total tract digestibility of dry matter and gross energy (p < 0.05). The ileal gene expression of glucose transporters was upregulated (p < 0.05) in challenged birds that received the CMC-supplemented diet. 6. In summary, increased digesta viscosity induced changes in the expression of nutrient transporter genes and decreased nutrient utilisation in Eimeria-challenged birds.

Effects of Starter Diet Energy Concentration on Nutrient Digestibility and Subsequent Growth Performance and Meat Yields of Broilers under Two Coccidiosis Control Programs.

An experiment was conducted to evaluate the live performance, processing characteristics, and apparent ileal digestibility (AID) of nutrients and energy (IDE) in broilers under two coccidiosis control programs (CCP) and fed three starter diet energy levels. Treatments were a factorial arrangement of CCP [in-feed diclazuril (ACD) or vaccinated after hatch (VAC)] and three starter diet energy levels [3008 (standard), 3058 (moderate), and 3108 (high) kcal/kg apparent MEn] achieved with different soybean oil concentrations. Birds were reared in floor pens (12 per pen) and received experimental starter diets from 0 to 18 d and common grower and finisher diets to 43 d. At d 11, VAC birds had higher (p < 0.05) excreta oocyst counts and lower (p < 0.05) plasma carotenoids, nutrient AID, and IDE than ACD birds. From 0 to 18 and 0 to 31 d, VAC decreased (p < 0.05) body weight gain and increased (energy × CCP, p < 0.05) feed conversion ratio of birds fed the moderate and high-energy diets but not for those fed the standard energy diet. From 0 to 43 d, VAC only increased the feed conversion ratio of birds fed the moderate-energy starter diet (energy × CCP, p < 0.05). Carcass yields were lower (p < 0.05) for VAC birds than for ACD birds, and interactive effects (p < 0.05) were observed for wing yield. In summary, increasing dietary lipid concentration to account for Eimeria-induced reductions in lipid digestibility during the starter period of coccidiosis-vaccinated broilers may exacerbate, rather than ameliorate, these impacts on bird performance.

PSI-14 Effect of dietary xylanase supplementation on growth performance, nutrient digestibility, and digesta viscosity of weaned pigs fed wheat-soybean meal-based diets

Abstract Xylanase supplementation can improve nutrient digestibility in pig diets by degrading cell wall non-starch polysaccharides and reducing digesta viscosity as well as promoting intestinal health of pigs after weaning. This study determined the effects of dietary xylanase supplementation on growth performance, apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of nutrients, and digesta viscosity in different digestive sites of weaned pigs. A total of 312 weaned pigs [body weight (BW) = 5.1 ± 0.9 kg] were weaned into 48 pens and assigned to one of six dietary treatments, each treatment with 8 pens, 6 to 7 pigs per pen, and sex ratios maintained within BW blocks. Experimental diets were formulated in a 3-phase nursery feeding program: Phase 1 (d 0 - d 7), Phase 2 (d 8 - d 21), and Phase 3 (d 22 – d 42). Experimental diets consisted of a wheat/soybean meal-based diet formulated to meet pig requirements (positive control, PC), the PC diet with reduction of 100 kcal of ME (negative control, NC), and the NC diet supplemented with either 900, 1,800, 3,600, or 7,200 units of xylanase. Feed disappearance and body weight were measured at d 7, 14, 21, and 42. Pen fecal score was assessed daily during d 0 to 14 and three times a week during d 15 to 28. On d 21 to 24 of the experiment (12 pigs per day), one pig per pen was selected for sample collection: ileal, cecal, and mid-colon digesta for viscosity and ileal digesta and feces for nutrient digestibility. Orthogonal polynomial contrasts were used to determine the linear and quadratic effects of increasing levels of xylanase in NC diets. Contrast analysis was used to compare PC and NC groups with xylanase-supplemented groups. Fecal score data were analyzed using the PROC FREQ procedure. Supplementing xylanase to NC diets did not improve pig growth performance (P &amp;gt; 0.05) through the nursery period. In wk 2 and wk 3, pigs fed the PC and NC diets had a greater (χ2 &amp;lt; 0.05) incidence of fecal scores 3 &amp; 4 (diarrhea) than the xylanase-supplemented pigs. The AID of DM and ATTD of crude protein, gross energy, and NDF were greater (P &amp;lt; 0.05) in the PC and 900-xylanase supplemented diets than in the other dietary treatments. In addition, the ATTD of NDF and ADF increased linearly (P &amp;lt; 0.1) in response to xylanase supplementation. Xylanase supplementation (900 to 7,200 U) decreased digesta viscosity in colon when compared with PC and NC diets. Overall, xylanase supplementation can improve nutrient digestibility, particularly at total tract level, and reduce viscosity in the hindgut, which could be related with decreasing the occurrence of looseness. However, the effects on growth performance were not expressive when xylanase was supplemented to wheat-soybean meal-based diets with reduction of 100 kcal of ME.

Evaluation of equations for predicting ileal nutrient digestibility and digestible nutrient content of broiler diets based on their gross chemical composition

The coefficient of apparent ileal digestibility (CAID) and ileal digestible contents (IDC) of nutrients of 56 diets using 10 feed ingredients were measured in broilers (21–24 d post-hatch). Diets contained varying inclusion levels of traditional and non-traditional ingredients and differed widely in chemical composition. The chemical composition and in vivo digestibility values were used to establish prediction equations for CAID and IDC of nutrients using stepwise multiple regression. The strength and accuracy of the developed equations were evaluated by root mean square error (RMSE), coefficient of determination (R2), adjusted R2 (adj. R2), and Akaikie’s Information Criteria (AIC). The bootstrap method was used to validate the choice of variables by stepwise selection method in the original equation based on their frequencies of selection. Selection of variables was validated if the variables that appear in the original stepwise model were selected in more than 30% of the 1000 bootstrap samples. A close agreement between the original equations and bootstrap resampling was observed for CAID of nitrogen (N) and energy and IDC of energy, starch, and calcium (Ca). Additionally, the original data was subjected to another run of stepwise regression analysis using the selected variables by bootstrapping. The initial regression showed that the CAID of N and energy was highly dependent on crude fibre (CF) and energy contents of the diets. The CAID of energy can be predicted (R2 = 0.89 and RMSE = 0.035) by CF, gross energy (GE), CF2, and starch-to-CF ratio (starch:CF). Calcium content had a positive influence, while phosphorus (P) content had a negative influence on the prediction of CAID of fat. The main variable to predict CAID and IDC of most nutrients was the dietary CF content. Based on the lowest RMSE and AIC, the best predictors for IDC of N were ash, N, fat, CF, CF2, and starch:CF, while the best predictors for IDC of energy were CF, GE, CF2, and starch:CF. The results of the original stepwise regression models and the stepwise regression with the selected variables from the bootstrap results for CAID of N, energy, fat, and DM, as well as IDC of energy, starch, and Ca, were the same with no differences in R2, Adj. R2, RMSE, and AIC. This method can be useful for developing stable and reproducible models using stepwise regression. However, an external validation is needed to confirm the use of these equations in commercial settings.

Applied Research Note: The impact of retention time during the conditioning process of a broiler starter diet on performance, apparent metabolizable energy, and apparent ileal digestibility of nutrients

Applied Research Note: The impact of retention time during the conditioning process of a broiler starter diet on performance, apparent metabolizable energy, and apparent ileal digestibility of nutrients

Novel sfericase protease improves amino acid digestibility of soybean meal and rapeseed meal in broiler chickens

ABSTRACT 1. Two experiments were conducted to explore the effects of an exogenous sfericase protease on the apparent ileal nutrient digestibility of soybean meal (SBM) and rapeseed meal (RSM) in broiler chickens. 2. In each experiment, a total of 256 sixteen-day-old male Cobb 500 broilers were fed one of four semi-purified experimental diets, comprising two different batches (A and B) of samples for either SBM (Exp. 1) or RSM (Exp. 2) without or with an exogenous sfericase (0 or 30,000 NFP/kg). Each experimental diet was fed to eight replicate pens of broiler chickens from 16 to 21 d of age (eight birds per cage), and ileal digesta were collected for measuring the digestibility coefficients. 3. In Exp. 1, the amino acid digestibility was greater (P < 0.05) in SBM B compared with SBM A for Arg and Val, and a similar trend (P < 0.1) was observed for Tyr, Leu and Thr. Exogenous sfericase increased (P < 0.10) digestibility of most of amino acids except Gly, His and Trp. There was an interaction between SBM source and sfericase, whereby digestibility of P, N and Asp was increased by sfericase for SBM B but not for SBM A. In Exp. 2, there was no interaction (P > 0.05) between RSM source and sfericase for ileal nutrient digestibility. Digestibility was greater in RSM A compared to RSM B for all non-essential AA and most essential AA (except for Trp), while the reverse was noted for Ca and P (P < 0.05). Exogenous sfericase increased (P < 0.1) digestibility for all amino acids except Cys and Met. 4. In conclusion, the current studies showed that both SBM and RSM batches influenced amino acid digestibility. Sfericase protease supplementation increased amino acid digestibility for both SBM and RSM. The digestibility effects were greater in the SBM batch with low digestibility for N and Asp which was in line with an increase in P digestibility.

Endogenous Enzyme Activities, Digestibility of Nutrients and Digestive Physiology as Affected by High Inclusion of Cottonseed Meal in Broiler Chicken Diets

A 3 × 3 factorial study examined the performance, endogenous enzyme activities and apparent ileal digestibility of nutrients, including energy, protein, starch, dry matter, amino acids and minerals of birds fed diets containing graded levels of cottonseed meal (CSM) with or without microbial enzymes. Nine iso-caloric and iso-nitrogenous diets were formulated mainly from wheat/sorghum/soybean meal. Three levels of CSM none (0%), low (5%, 10%, and 15%) or high (6%, 12%, and 18%) in the starter, grower, and finisher diets, respectively, were included. The diets were supplemented with three levels of a composite xylanase and beta-glucanase product at 0, 100 or 150 mg/kg diet. Each of the nine dietary treatments was randomly assigned to 6 replicates, with 10 birds per replicate. Feed intake (FI) and weight gain (WG) were recorded on day 10, 24 and 35, and feed conversion ratio (FCR) was obtained from the data, while enzyme activities and nutrient digestibility were measured on samples collected on day 10 and 24, and day 24 only, respectively. Feed intake up to day 35 decreased (P &lt; 0.05) significantly with increasing enzyme supplementation. On the CSM-containing diets, enzyme supplementation at 100 or 150 mg/kg improved WG up to day 24, with the heaviest birds (1514 g/b) observed in the low CSM with 100 mg/kg enzyme group. Enzyme supplementation improved (P &lt; 0.01) FCR all through the growth phases and also improved (P &lt; 0.05) ileal crude protein and starch digestibility. High levels of CSM decreased the digestibility of starch, but this was improved (P &lt; 0.05) by enzyme supplementation, showing an interaction between CSM and microbial enzyme on starch digestibility. The digestibility of arginine, glutamic acid and threonine improved with increased CSM inclusion, and that of methionine improved with increased enzyme supplementation. There was an interaction effect (P &lt; 0.01) between CSM and enzyme on magnesium digestibility. Cottonseed meal inclusion improved the digestibility of copper and potassium and reduced the digestibility of phosphorus, while that of calcium and manganese was increased (P &lt; 0.01) with enzyme supplementation. At day 10, lipase activity was increased (P &lt; 0.05) by higher CSM levels, while on day 24, general proteolytic activity was highest (P &lt; 0.05) when 100 mg enzyme was supplemented in the diet. These results indicate that relatively high levels of CSM in diet have no negative effects on the growth and digestive physiology of broiler chickens when supplemented with xylanase and β–glucanase.

Effects of dietary xylanase supplementation on growth performance, intestinal health, and immune response of nursery pigs fed diets with reduced metabolizable energy.

This study aimed to investigate the effects of xylanase on growth performance and intestinal health of nursery pigs fed diets with reduced metabolizable energy (ME). One hundred ninety-two pigs at 8.7 kg ± 0.7 body weight (BW) after 7 d of weaning were allotted in a randomized complete block design with initial BW and sex as blocks. Eight dietary treatments consisted of 5 ME levels (3,400, 3,375, 3,350, 3,325, and 3,300 kcal ME/kg) below the NRC (2012) requirement and 4 levels of xylanase (0, 1,200, 2,400, and 3,600 XU/kg) to a diet with 3,300 kcal ME/kg. All pigs received their respective treatments for 35 d in 2 phases, pre-starter (14 d) and starter (21 d). On day 35, eight pigs in 3,400 kcal/kg (CON), 3,300 kcal/kg (LE), and 3,300 kcal/kg + 3,600 XU xylanase/kg (LEX) were euthanized to collect jejunal tissues and digesta for the evaluation of mucosa-associated microbiota, intestinal immune response, oxidative stress status, intestinal morphology, crypt cell proliferation, and digesta viscosity as well as ileal digesta to measure apparent ileal digestibility. Data were analyzed using the MIXED procedure on SAS 9.4. The LE increased (P < 0.05) jejunal digesta viscosity, tended to have decreased (P = 0.053) relative abundance of Prevotella, and tended to increase (P = 0.055) Lactobacillus. The LE also increased (P < 0.05) the concentration of protein carbonyl whereas malondialdehyde, villus height (VH), villus height to crypt depth ratio (VH:CD), apparent ileal digestibility (AID) of nutrients, and finally average daily feed intake were decreased (P < 0.05). The LE did not affect average daily gain (ADG). The LEX decreased (P < 0.05) digesta viscosity, increased (P < 0.05) the relative abundance of Prevotella, decreased (P < 0.05) Helicobacter, decreased (P < 0.05) the concentration of protein carbonyl, tended to increase (P = 0.065) VH, and decreased (P < 0.05) VH:CD and crypt cell proliferation. Moreover, LEX increased (P < 0.05) the AID of dry matter and gross energy and tended to increase (P = 0.099; P = 0.076) AID of crude protein, and ether extract. The LEX did not affect ADG but did tend to decrease (P = 0.070) fecal score during the starter phase. Overall, reducing ME negatively affected intestinal health parameters and nutrient digestibility without affecting growth. Supplementation of xylanase mitigated some of the negative effects observed by ME reduction on intestinal health and digestibility of nutrients without affecting growth.

Effects of a Bentonite Clay Product and a Preservative Blend on Ileal and Fecal Nutrient Digestibility in Pigs Fed Wheat Naturally Contaminated with Deoxynivalenol.

The objectives were to determine the effects of dietary deoxynivalenol (DON) on apparent ileal digestibility (AID) of nutrients and to evaluate the efficacy of a bentonite (BEN) and a preservative blend (PB) product for alleviating DON effects on the nutrient digestibility of pigs. Twelve crossbred barrows with an initial body weight of 69.4 kg (standard deviation = 3.5) equipped with a T-cannula in the distal ileum were allotted a triplicated 4 × 2 incomplete Latin square design with four dietary treatments and two periods. Dietary treatments were (1) an uncontaminated diet, (2) a contaminated diet (CD) mainly based on contaminated wheat with 1.6 mg/kg DON, (3) CD + 0.25% PB consisting of preservation components as major sources, antioxidants, microorganisms, and amino acids (AA), and (4) CD + 0.25% BEN. The AID and ATTD of dry matter, organic matter, crude protein, most minerals, and most AA were not affected by DON contamination. Dietary DON decreased the AID and ATTD of sodium (p < 0.05) but were restored by supplementing the PB product (p < 0.05). The AID of zinc was increased (p < 0.05) by dietary DON, but supplementing BEN decreased zinc digestibility (p < 0.05). The AID of Arg, Ile, Thr, and Asp was decreased (p < 0.05) by BEN addition. In conclusion, dietary DON affected the digestibility of some minerals but not AA in pigs. Supplemental BEN can negatively affect the nutrient digestibility of some minerals and AA in pigs. The addition of a PB product in pig diets can restore digestibility of sodium but not of other nutrients. Based on these observations, feed additives for alleviating DON effects on nutrient digestibility of pigs can be carefully selected by swine diet formulators.

273 Effects of Xylanase Supplementation in Diets with Reduced Metabolizable Energy and Supplemental Fat on Intestinal Health, Mucosa Associated Microbiota and Growth Performance of Nursery Pigs

Abstract This study aimed to investigate the effects of reducing metabolizable energy (ME) below the requirement by reducing supplemental fat on intestinal health and growth performance of nursery pigs. One hundred and ninety-two newly weaned pigs at 7.3 ± 0.6 kg BW were allotted in a RCBD with sex and initial BW as blocks. Pigs were assigned to one of 8 dietary treatments with varying ME levels (3,400, 3,375, 3,350, 3,325, and 3,300 kcal/kg ME) by reducing supplemental fat and increasing xylanase (X0: 0, X40: 1,200, X80: 2,400 and X120: 3,600 XU/kg of feed) in ME deficient diets by 100 kcals/kg. Pigs were fed diets for 35 d in 2 phases (14 d and 21 d, respectively) and growth performance was measured at the end of each phase. Phase 2 diet had titanium dioxide (0.4%) as indigestible external marker to measure ileal digestibility of nutrients. At d 35, a pig representing the median BW within each pen from 3 dietary treatments (ME at 3,400 and 3,300 kcal/kg ME with or without xylanase) were euthanized for sampling jejunal mucosa, jejunal tissue, and ileal digesta to analyze intestinal health parameters, mucosa associated microbiota, and apparent ileal digestibility (AID) of nutrients. Data were analyzed using Mixed procedure of SAS 9.4. Overall, reducing ME level had no effect on growth performance of nursery pigs. However, reducing ME by 100 kcal/kg ME below the requirement increased (P &amp;lt; 0.05) digesta viscosity (1.7 to 2.2 cP) and protein carbonyl (0.18 to 0.40 nmol/mg), tended to change the relative abundance of Prevotellaceae (P = 0.062, 49 to 23%) and Lactobacillaceae (P = 0.086, 7 to 19%), reduced (P &amp;lt; 0.05) villus height (467 to 433 µm) and villus height to crypt depth ratio (1.80 to 1.64) in the jejunum, and reduced (P &amp;lt; 0.05) AID of DM (59.5 to 47.3%), gross energy (59.1 to 43.0%), crude protein (63.4 to 44.6%), and ether extract (67.7 to 55.2%). Xylanase supplementation decreased (P &amp;lt; 0.05) digesta viscosity (2.2 to 1.82 cP) and protein carbonyl (0.40 to 0.17 nmol/mg), increased the relative abundance of Prevotellaceae (20.22 to 61.56%), increased villus height (433 to 462 µm) and villus height to crypt depth ratio (1.64 to 1.99) in the jejunum, and increased (P &amp;lt; 0.05) AID of DM (47.3 to 58.7%), and gross energy (42.9 to 56.0%). In conclusion, reducing ME (100 kcal/kg below the requirement) by reducing supplemental fat (by 2% unit) impaired intestinal health, reducing ability of the pigs to digest feeds whereas xylanase supplementation appeared to mediate some of the negative effects seen by energy reduction by improving intestinal morphology, reducing oxidative damage products, and diversity of the mucosa-associated microbiota.

Short communication: Estimation of ileal digestibility in chickens using single- and dual-tracer methods

Fractionation of digesta, as occurs during gastrointestinal transit in chickens, complicates accurate measurements of ileal digestibility using tracers. Dual-tracer methods using separate tracers for solid and fluid digesta phases may improve the accuracy of digestibility measurements when assumptions of the single tracer method are violated. The aim of the present study was to compare the apparent ileal digestibility (AID) of nutrients calculated with single- and dual-tracer methods in chickens fed diets varying in particle size, anticipating digesta phase separation in the proximal gastrointestinal tract. A total of 112 Dekalb White (BW: 1.53 ± 0.107 kg) and 112 Bovans Black (BW: 1.79 ± 0.127 kg) 29-week-old laying hens were distributed over 32 pens (seven birds/pen). Within breed, pens were randomly assigned to one of two experimental diets (coarse vs fine oat hulls; n = 8 replicate pens per diet/breed combination). Diets were supplemented with TiO2 (3 g/kg) and Co-EDTA (2 g/kg). On days 34, 35, or 36, birds were euthanised and digesta from the ileum was collected for tracer and nutrient analyses. Apparent ileal digestibility was subsequently calculated by single- and dual-tracer methods. Although coarse oat hulls were hypothesised to increase the fractionation of solid and fluid digesta phases, no breed or diet × method interactions were found. Using a single tracer method based on TiO2, AID of nitrogen (N) was overestimated by 3%-units (P < 0.01) compared with the dual-tracer method, whereas AID estimates of DM, starch, fat, and non-starch polysaccharides did not differ (P > 0.09) and precision of all AID estimates was improved. In conclusion, these results show that although from a conceptual perspective, dual-tracer methods are presumed to better account for the variation in flow behaviour of different digesta phases, AID estimates obtained by the commonly used single tracer method using solid-phase tracer TiO2 were more precise and only marginally differed from estimates obtained by a dual-tracer method using distinct tracers for solid (TiO2) and liquid (Co-EDTA) digesta phases. Considering technical and economical constraints, the single tracer method may thus be the method of choice in many situations. Only when digestibility of proteins or amino acids is of specific interest, single tracer methods using a solid-phase tracer may not suffice. Nevertheless, for both single- and dual-tracer methods, tracer selection is critical, and the choice of tracers should depend on the nutrient(s) of interest.

The Chemical Composition of Soyhulls and Their Effect on Amino Acid and Nutrient Digestibility in Laying Hens during the Peak of Production.

This study investigates the chemical composition of soyhulls (SHs) as an alternative feed ingredient and their effect on nutrient and amino acid (AA) digestibility in laying hens during peak production. A total of 200 golden brown hens (28 weeks old) were subjected to random allocation across 5 dietary treatments: a corn-soybean meal (SBM) reference diet and 4 test diets with 25% SHs from different mills (SH1, SH2, SH3, and SH4). Each treatment was replicated four times with ten birds per replicate. Digesta samples were collected during three phases (28-32, 32-36, and 36-40 weeks of age) to measure apparent metabolizable energy (AME), the apparent ileal digestibility (AID) of nutrients, and the standard ileal digestibility (SID) of AAs. The SBM diet had 30.0% crude protein (CP) and 3.78% crude fiber (CF), while the SH diets had 21.0 to 21.5% CP and 11.6% CF. The findings revealed that the AME was lower (p < 0.05) with SH diets (2404 kcal/kg) compared to the SBM diet (2627 kcal/kg) in all three phases. The SH diets had a lower AID of dry matter (DM), crude protein (CP), ash, ether extract (EE), and crude fiber (CF) than the SBM diet by an average of 2.88, 2.25, 4.93, 4.99, and 3.36%, respectively. The AID of nitrogen-free extract (NFE) was higher in the SH diets than the SBM diet by 3.42% in all three phases (p < 0.05). The SH diets had lower uric acid excretion (about 66.93 mg/100 mL) than the SBM diet (about 76.43 mg/100 mL) on average in all three phases. The SH diets had a lower SID of arginine, histidine, isoleucine, lysine, cysteine, valine, and tyrosine than the SBM diet by 2 to 10%, while the SID of methionine was higher in the SH diets than the SBM diet by 2.2% on average in all three phases (p < 0.05). The SH from Sadiq Brother Feed (SH1) had the highest AME and AID of DM, ash, CP, EE, CF, and the SID of AA among the SH diets. These results indicate that SH can partially replace SBM in laying hen diets, but the source and quality of SH should be considered.

Efficacy of soy protein concentrate replacing animal protein supplements in mucosa-associated microbiota, intestinal health, and growth performance of nursery pigs.

This study investigated the effects of using soy protein concentrate (SPC) to replace animal protein supplements on mucosa-associated microbiota, intestinal health, and growth performance of nursery pigs. Fifty-six newly weaned pigs (BW= 6.4±0.6kg) were allotted to 5 treatments in a randomized complete block design. Pigs were fed for 35d in 3 phases (P; 1, 2, 3) for 10, 12, 13d, respectively. Dietary treatments were: (1) basal diet with fish meal (P1: 4%, P2: 2%, and P3: 1%), poultry meal (P1: 10%, P2: 8%, and P3: 4%), and blood plasma (P1: 4%, P2: 2%, and P3: 1%), where SPC replacing none (NC); (2) basal diet with SPC replacing fish meal (RFM); (3) basal diet with SPC replacing poultry meal (RPM); (4) basal diet with SPC replacing blood plasma (RBP); and (5) basal diet with SPC replacing all animal protein supplements (PC). Growth performance was recorded for each phase. Pigs were euthanized on d 35 to collect jejunal mucosa and tissue to evaluate intestinal health and microbiota, and ileal digesta to measure apparent ileal digestibility (AID) of nutrients. Data were analyzed using the MIXED procedure of SAS. Overall, RFM, RPM, and RBP did not affect growth performance, whereas PC decreased (P<0.05) ADG and ADFI. The RPM increased (P<0.05) Prevotella stercorea and decreased (P<0.05) Helicobacter rappini. The PC decreased (P<0.05) H.rappini, whilst increasing (P<0.05) Prevotella copri, Propionibacterium acnes, and Pelomonas aquatica. The RFM tended to increase (P=0.096) immunoglobulin A in the jejunum. The PC tended to decrease (P=0.078) jejunal crypt cell proliferation. There were no differences in the villus height, AID of nutrients, intestinal inflammation, and intestinal oxidative stress among treatments. In conclusion, SPC can replace fish meal, poultry meal, or blood plasma individually without affecting growth performance and intestinal health, and AID of nutrients of nursery pigs. Particularly SPC replacing poultry meal benefitted intestinal health by reducing H.rappini and increasing P.stercorea. However, SPC replacing all three animal protein supplements reduced growth of nursery pigs mainly by reducing feed intake.

The ileal and total tract digestibility fibre and nutrients in pigs fed high-fibre cereal-based diets provided without and with a carbohydrase complex.

The effect of carbohydrase can be variable according to the complexity of cereal grains and co-products. Studies on the effect of carbohydrase on cereal diets varying in complexity are scarce. This study was conducted to investigate the apparent ileal (AID) and total tract digestibility (ATTD) of energy, fibre and nutrients in pigs fed diets based on cereal grains and co-products without and with supplementation with a carbohydrase complex in the form of xylanase, arabinofuranosidase and β-glucanase. The experiment was carried out as an 8×4 Youden Square design (eight diets and four periods by two blocks) using 16 growing pigs (33.3±0.8kg) surgically fitted with a T-cannula in the terminal ileum. The pigs were fed eight experimental diets based on either - maize, wheat, rye, or a wheat and rye mix that were provided with or without enzyme supplementation. The AID and ATTD of DM, organic matter, energy, CP, fat, starch, and soluble and insoluble non-starch polysaccharides (NSPs) were studied using titanium dioxide as an indigestible marker. There was a cereal type effect (P<0.05) of the AID of most of the nutrients investigated but ash and NSP and some of its constituents but with no interactions between cereal types and carbohydrase supplementation (P>0.05). The ATTD of nutrients in the large intestine was mainly influenced by the fibre composition and was significantly lower (P<0.001) for NSP, protein and energy for the Maize than the other diets. Supplementation of the cereal diets with the carbohydrase complex partially degrades arabinoxylan (AX) and β-glucan giving rise to a generally higher AID of high-molecular weight arabinoxylan (P=0.044), starch (P=0.042), a tendency (P<0.10) of higher AID of non-cellulosic polysaccharide glucose residue (β-glucan) and soluble arabinoxylan (AX) whereas none of the other components were affected (P>0.05). Collectively, the results indicate that the carbohydrase complex degrades AX in the stomach and small intestine, leading to a higher AID but with no influence on the ATTD of fibres, nutrients, and energy.

Influence of partial replacement of ground barley with whole barley and exogenous enzyme supplementation in pelleted diets on growth performance, nutrient utilisation and foregut development in broiler starters

A 3 × 2 factorial arrangement of treatments, evaluating three inclusion levels of whole barley (WB; 0, 141, 282 g/kg) in a barley-based diet and two levels of carbohydrase (Carb; 0 and 0.15 g/kg of feed), was used. The AMEn and standardised digestible amino acid contents of the test barley were used in formulating the basal diet. Whole barley was added to the diet at the expense of ground barley (GB; 3.0 mm sieve size). The diets contained 5.0 g/kg titanium dioxide as an inert marker. Each of the six experimental diets was pelleted and offered ad libitum to six replicate cages (eight birds/cage). Body weights and feed intake were recorded weekly throughout the 21-d trial. The AMEn was determined using the classical total excreta collection method (17–20 d). On d-21, ileal digesta were collected from the terminal ileum to determine the coefficient of apparent ileal digestibility of nutrients. Jejunal digesta were collected for the determination of intestinal digesta viscosity. There was no significant (P > 0.05) interaction between WB and Carb for any measured parameter. Compared to the birds fed GB diets, those fed WB at 141 g/kg had a higher (P < 0.05) weight gain by 36 g/bird, with no effect on the feed intake or feed efficiency. The inclusion of WB tended (P = 0.058) to enhance N digestibility from 0.741 in GB diets to 0.775 in diets with 282 g/kg WB. Irrespective of Carb supplementation, compared to the GB diet, WB inclusion at 141 and 282 g/kg improved (P < 0.001) starch digestibility (by 3.6 % and 5.7 %, respectively) and AMEn (by 1.85 % and 2.89 %, respectively). These improvements were not associated with any impact (P > 0.05) on gizzard development. Jejunal digesta viscosity was not influenced (P > 0.05) by WB inclusion. Adding Carb increased starch digestibility and energy utilisation by 2.24 % and 0.12 MJ/kg, respectively, possibly due to 0.35 cP reduction in jejunal digesta viscosity (P < 0.05) by the supplemental Carb. Overall, WB could be included in barley-based broiler starter diets up to 282 g/kg of diet with no adverse effects on performance.

Effect of Particle Size of Wheat and Barley Grain on the Digestibility and Fermentation of Carbohydrates in the Small and Large Intestines of Growing Pigs

The objective of this investigation was to study the effects of different cereal types, barley and wheat, with different particle sizes (PS) on the recovery of ileal digesta and fecal excretion, digestion of nutrients and fiber components, mean transit time (MTT), and short-chain fatty acid content and composition in growing pigs studied in two experiments. Five barrows with ileal cannulas (initial BW 35.9 ± 1.5 kg) in Experiment 1 and thirty-two castrated pigs (30.8 ± 1.3 kg) in Experiment 2 were fed four different diets: barley fine, barley coarse, wheat fine and wheat coarse diets. The cereal type and PS did not influence the relative weight of the small and large intestines and pH of digesta, whereas MTT in the large intestine of pigs fed the coarse barley diet was lower compared to pigs fed other diets (p &lt; 0.05). Pigs fed the coarse barley diet had lower apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of nutrients and fiber (p &lt; 0.05), whereas pigs fed the fine barley diet had similar AID and ATTD to pigs fed wheat fine and coarse diets (p &lt; 0.05). In conclusion, the barley diet was more influenced by PS in comparison to wheat, thereby inducing lower AID and ATTD of nutrient.

English

A research study was executed to evaluate the dietary influence insoluble fiber obtained from different sources on various production parameters in the broilers. A total of 180 1d old mixed sex Ross 308 broiler chicks were procured and placed randomly to 5 treatment groups of 6 replicates each. There were 36 broilers in each treatment group. The broilers in first treatment group were fed basal diet whereas broilers in all other groups were fed ration containing insoluble fiber (oat and rice hulls wood shavings and sugarcane bagasse) each of which was included at level of 3%. All the diets were offered to the broilers in mesh form during the entire experimental duration of 7 weeks. The broilers fed oat hull based diet has significantly improved growth performance compared to those fed other experimental diets and control. Carcass traits including dressed weight with and without giblet breast and leg quarter yields were significantly higher by the addition of oat hulls compared to other dietary treatment groups. The broiler fed oat hulls and sugarcane bagasse based rations has significantly improved relative weight of the gizzard compared to other treatment groups. Gut health parameters including villus height and villus height to crypt depth ratio were increased by 15 and 34% whereas crypt depth was decreased by 34% by the addition of oat hulls in comparison with other dietary treatments. Apparent ileal digestibility of various nutrients including dry matter crude protein and amino acids was increased significantly by feeding oat hulls based ration to the broilers. In short dietary supplementation of sugarcane bagasse and oat hulls has resulted in an improved production and carcass parameters better intestinal histo-morphology and increased digestibility of various nutrients in the broilers.

Effect of Bacterial Phytase on Growth Performance, Nutrient Utilization, and Bone Mineralization in Broilers Fed Pelleted Diets.

The influence of a bacterial 6-phytase on growth performance, coefficient of apparent ileal digestibility (CAID) of nutrients, blood parameters, and bone mineralization in broilers was evaluated. A total of 630 one-day-old male broilers were allocated to 7 dietary treatments, including positive control (PC) diet containing dicalcium phosphate, the PC marginally reduced in available P (avP) by 0.1% and calcium (Ca) by 0.2% vs. PC (NC1) or moderately reduced by 0.15 and 0.3% vs. PC (NC2), respectively, and four further diets comprising the NC1 and NC2 supplemented with 500 or 1000 FTU/kg of phytase in starter and finisher phases. A constant Ca to avP ratio was maintained across all diets. The body weight gain (BWG) and feed per unit gain (FCR) of birds fed NC1 and NC2 diets supplemented with phytase (500 and 1000 U/kg) was equivalent to that of birds fed the PC diet at 35 days. Phytase supplementation in the NC1 diet linearly increased the CAID of nitrogen (N) (p < 0.01), phosphorus (P) (p < 0.01), and Ca (p < 0.05). Additionally, phytase reduced (p < 0.01) excreta P concentration by approximately 27%, improved (p < 0.001) toe ash, and tended to increase tibia ash (p = 0.08), comparable with the PC. In conclusion, the addition of bacterial 6-phytase dosed in the range of 500-1000 FTU/kg was effective in replacing 1.5 g/kg avP and 3 g/kg Ca in broilers fed pelleted diets, using bone quality, BWG, and FCR as outcome measures.