Digestible Energy Research Articles

Development of Prediction Equations for Digestible and Metabolizable Energy in 15 Cereal Processing By-Products Fed to Growing Pigs

The study was conducted to determine the nutrient digestibility and digestible (DE) and metabolizable energy (ME) of 15 cereal processing by-products and to develop prediction equations for DE and ME based on the chemical composition in growing pigs. A total of 36 crossbred pigs were chosen and divided into three blocks according to a three 12 × 3 Youdin square experimental design. Twelve pigs in each block were allocated into six diets including a basal diet and five test diets. The feeding experiment included three periods, and each dietary treatment contained six replicates. Each period lasted 12 days, including 7 d of dietary adaption and 5 d of total feces and urine collection. The results showed that the coefficients of variation for EE, NDF, ADF, CP, and GE among 15 cereal processing by-products were 86.78%, 49.82%, 51.14%, 14.95%, and 6.26%, respectively. There were significant differences in DE, ME, and ME/DE (DM basis) among 15 cereal processing by-products (p < 0.05), ranging from 11.55 MJ/kg to 17.64 MJ/kg, from 10.90 MJ/kg to 17.40 MJ/kg, and from 89.41% to 98.63%, respectively. The digestibility of GE, DM, NDF, ADF, and CP showed a significant difference among 15 cereal processing by-products (p < 0.05). The DE and ME contents showed a negative correlation to NDF and ADF (p < 0.05), and the prediction equations for DE and ME (as-fed basis) were DE (MJ/kg) = −0.4597 × ADF (%) + 0.5988 × GE (MJ/kg) + 6.0138 (R2 = 0.74; p < 0.05) and ME (MJ/kg) = 1.0440 × DE (MJ/kg) − 1.1235 (R2 = 0.98; p < 0.05). On a DM basis, the optimal prediction equations for DE and ME were DE (MJ/kg DM) = −0.1451 × NDF (%) + 0.3026 × CP (%) + 13.8595 (R2 = 0.72; p < 0.05) and ME (MJ/kg DM) = 1.1155 × DE (MJ/kg DM) + 0.0363 × ADF (%) − 2.3412 (R2 = 0.99; p < 0.05). In conclusion, there were large variations in the chemical composition, nutrients digestibility, and available energy among the 15 different samples of cereal processing by-products. It is reasonable to develop prediction equations for DE and ME based on the chemical composition of cereal by-products for growing pigs.

Standardized Ileal Digestibility of Amino Acids in Hybrid Rye Ground to Two Particle Sizes and Fed With or Without Multienzyme Supplement to Young Growing Pigs.

A newly developed hybrid rye with enhanced ergot resistance has potential as an alternative energy source for pigs. An experiment was conducted to evaluate the effects of particle size (PS) and multienzyme supplement (MES) on the apparent total tract digestibility (ATTD) of energy and nutrients and the standardized ileal digestibility (SID) of amino acids (AA) in hybrid rye fed to growing pigs. Bono and Gatano, two hybrid rye varieties, were ground to either a coarse (1111 and 1210 μm) or a fine (594 and 717 μm) PS using a hammer mill. Eighteen ileal-cannulated barrows (initial BW = 18.2 ± 1.0 kg) were randomly assigned to 1 of 9 dietary treatments in a replicated 9 × 3 incomplete Latin square design to give six observations per treatment. Among the nine experimental diets, eight featured two hybrid rye varieties (Bono or Gatano), either coarsely or finely ground, as the only source of AA with or without MES, while an N-free diet was used to estimate the endogenous losses of AA at the distal ileum. All diets contained titanium dioxide as an indigestible marker. Each period lasted 9 days, with the first 5 days being for adaptation followed by 2 days each for faecal and ileal digesta collection. Data were analysed using the MIXED procedure of SAS, with the final model having variety, PS, MES, their two-way interactions, and a three-way interaction. No interactions were noted except that the apparent ileal digestibility and SID of crude protein (CP) and most AA in Gatano had greater effects of MES than Bono (Variety × MES; p < 0.05). The ATTD of dry matter (DM), gross energy (GE) and CP were greater (p < 0.05) in Bono diets than in Gatano diets. Finely ground hybrid rye diets had higher (p < 0.05) ATTD of neutral detergent fibre assayed with a heat stable amylase and expressed inclusive of residual ash (NDF) and ether extract compared to coarsely ground hybrid rye diets. Dietary MES supplementation increased (p < 0.05) the ATTD of DM, GE, CP, NDF, acid detergent fibre expressed inclusive of residual ash, and ash in hybrid rye diets. In conclusion, the nutrients digestibility of hybrid rye can be affected by its variety. PS reduction improved the nutrient digestibility in hybrid rye, and MES supplementation improved the energy and AA digestibility in hybrid rye fed to growing pigs.

Evaluation of Associative Effects on Degradability, Fermentation Parameters, and In Vitro Methane Production as a Result of Variation in the Ruminants Diets Constituents

This study aimed to investigate the effect of different forage sources and forage-to-concentrate ratios on digestibility, energy concentration, fermentation parameters, and in vitro estimate of methane. The experiment was carried out in a completely randomized design using a 3 × 6 factorial arrangement with three forages varying the chemical composition (pineapple crop waste silage [PS], corn silage [CS], and Tifton hay [TH]) associated with concentrate feed (C) in six combinations, using triplicates for each ratio. We evaluated in vitro digestibility, metabolizable and net energy, pH, redox potential, volatile fatty acids (VFA), and methane production. The in vitro neutral detergent fiber digestibility (IVNDFD) decreased (p = 0.0011) with the inclusion of concentrate. It was also affected by the forage source, but this fact was only observed in CS up to the 50:50 ratio. In TH, this fact occurred from the 80:20 ratio, and this behavior was not observed in the PS. Data on methane production, VFA, and fermentation parameters varied according to forage source and concentrate inclusion. In conclusion, the inclusion of concentrate reduces methane production, increasing the system’s energy contribution. Overall, the different forage sources and the inclusion of concentrate change digestion and fermentation parameters.

Energy Values and Standardized Ileal Digestibility of Amino Acids in Fermented Soybean Meal Fed to Growing Pigs.

This study aimed to evaluate the digestible energy (DE), metabolizable energy (ME), and standardized ileal digestibility (SID) of amino acids (AA) in fermented soybean meal (FSBM) fed to growing pigs. In experiment 1, twenty-two growing pigs (Duroc × Landrace × Yorkshire; 32.0 ± 4.2 kg BW) were fed one of 11 diets in a replicated 11 × 3 incomplete Latin square design to determine the DE and ME of FSBM. The diets included a corn-based diet and 10 experimental diets formulated by replacing the corn with 29.10% FSBM. In experiment 2, eleven growing pigs (Duroc × Landrace × Yorkshire; 24.3 ± 2.3 kg BW) were surgically equipped with a T-cannula and arranged in an 11 × 6 incomplete Latin square design with 11 diets and six periods. The diets included an N-free diet and 10 experimental diets containing 40% FSBM as the sole source of AA. The results showed that the contents of dry matter (DM), gross energy, crude protein, crude fiber, neutral detergent fiber, acid detergent fiber, calcium, and phosphorus averaged 91.83% (ranging from 89.24 to 94.55%), 18.44 MJ/kg (ranging from 18.00 to 18.95 MJ/kg), 50.63% (ranging from 50.00 to 51.81%), 4.51% (ranging from 3.41 to 5.40%), 9.17% (ranging from 7.02 to 10.30%), 6.38% (ranging from 4.97 to 7.45%), 0.32% (ranging from 0.29 to 0.34%), and 0.67% (ranging from 0.61 to 0.84%), respectively. The average DE and ME were 17.55 and 16.33 MJ/kg DM, respectively, with ranges of 15.72 to 18.80 MJ/kg DM and 14.30 to 17.72 MJ/kg DM, respectively. Significant differences were observed in the SID of essential AA (p < 0.05), except for Thr and Arg. The SID of Lys, Met, Trp, and Thr ranged from 68.13 to 83.27% (mean = 76.62%), 62.23 to 89.30% (mean = 75.25%), 72.30 to 90.29% (mean = 80.96%), and 74.17 to 84.41% (mean = 77.90%), respectively. These results indicate significant variability in chemical composition, energy content, and the SID of AA among the selected FSBM samples. The chemical composition of FSBM can be used to predict DE and ME values.

Effects of Alanyl-Glutamine Dipeptide Supplementation on Growth Performance, Nutrient Digestibility, Digestive Enzyme Activity, Immunity, and Antioxidant Status in Growing Laying Hens.

Alanyl-glutamine (Aln-Gln), a highly soluble and stable Glutamine-dipeptide, is known to improve the performance of poultry birds. This study aimed to investigate the effect of Aln-Gln during the rearing period on growth performance, nutrient digestibility, digestive enzyme activity, immunity, antioxidant status and relative gene expression of Hy-Line brown hens. A total of 480 healthy day-old Hy-line brown chicks with similar body weights were randomly divided into four dietary groups (8 replicates/group and 15 birds/replicate). Groups A, B, C and D were fed diets containing 0%, 0.1%, 0.2% and 0.3% Aln-Gln, respectively, for 6 weeks. The body weight (BW) and average daily gain (ADG) were higher in hens fed test diets compared with the control (p < 0.05). The feed conversion ratio (FCR) was better in test groups as compared to the control group (p < 0.05). The ADFI showed no significant difference between the groups. Dietary treatments had no effect on dry matter (DM), organic matter (OM) and crude fiber (CF) digestibility. The Aln-Gln also improved gross energy (GE) and crude protein (CP) digestibility (p < 0.05). It has also increased IgG levels in groups C and D. IgM levels were similar to the control in B, C and D. The Aln-Gln increased IL-1 in B and C, IL-2 in C and D, and IL-6 in all test groups (p < 0.05). The supplementation of Aln-Gln had no effect on serum antioxidant indices like CAT, MDA, GSH-PX, GSH, and SOD in 42-day-old growing hens. Aln-Gln supplementation had no significant effect (p > 0.05) on the activity of amylase and lipase, however, a significant improvement (p < 0.05) in the activities of trypsin and chymotrypsin was observed in the test groups. Supplemented Aln-Gln levels in the birds' diets led to an increase in the expression of genes related to growth factors (IGF-1, IGFBP-5), immune markers (IL-1, IL-2, IL-6) and antioxidant status (GSH-Px1), as compared to control group. Aln-Gln supplementation in Hy-Line brown hens during their growing period improved growth, nutrient digestibility, immunity and digestive enzymes activity. These findings suggest that Aln-Gln is a promising dietary additive for enhancing poultry performance.

The effect of increasing canola oil and soybean oil addition to beef cattle rations based on corn silage and barley grain on the in vitro ruminal gas production and rumen fermentation

AbstractThe purpose of the current experiment was to determine the effects of ruminal fermentation parameters of the additions of canola or soybean oils at different rates (4, 8 and 12%) to beef cattle total mix rations (TMR), based on corn silage and barley grain. The addition of 4% soybean oil to TMR positively affected in vitro gas production, net energy lactation (NEL), metabolic energy (ME), and organic matter digestion (OMd). The additions of 8% and 12% of soybean oil to TMR linearly decreased ME, NEL and OMd (p &lt; 0.05). The additions of 4, 8 and 12% canola oil to the TMR linearly decreased the in vitro gas production and estimated fermentation values (ME, NEL and OMd) (p &lt; 0.05). All doses of soybean or canola oils in TMR reduced the molarities of total short‐chain fatty acids (tSFCA), acetic (AA), butyric (BA), propionic (PA), valeric (VA), iso‐valeric (IVA) and iso‐butyric acids (IBA) for in vitro fermentation fluid (p &lt; 0.05). There was a negative correlation between the increasing dietary stearic, oleic and linoleic acid and the end‐products of in vitro rumen fermentation. However, increasing dietary α‐linolenic acids had no adverse effect on in vitro ruminal fermentation end‐products. As a result, 4% addition of the soybean oil, which included a higher rate of α‐linolenic acid and saturated fatty acids and a lower rate of oleic, linoleic acids according to those of canola oil, to the TMR positively affected in vitro ruminal fermentation. In addition, the ≥8% addition of canola or soybean oil adversely affected the in vitro fermentation values.

Effect on Growth Performance and Nutritive Value of Cultivated Azolla filiculoides As An Alternative Feedstuff for Ruminant.

Azolla filiculoides is a tiny, free-floating aquatic fern and has a potential alternative protein and fibre source for ruminants, was investigated for its cultivation optimisation and feedstuff suitability. Study 1 was conducted to investigate the influence of different fertiliser types (control, broiler manure, sheep manure, cow manure) and concentrations (0.25 g/L-1.25 g/L) on the growth performance (fresh weight, doubling time, relative growth rate) and nutrient composition (dry matter, ash, crude protein, crude fibre, crude fat) of A. filiculoides. The optimised type of fertiliser and concentration in Study 1 were further adopted in Study 2 to evaluate the effect of different fertiliser processing methods on the growth performance, nutritive value and in vitro rumen digestibility of A. filiculoides upon cultivation. The findings in Study 1 showed that cultivation of A. filiculoides using sheep manure at the concentration of 1.00 g/L is the best resulted in the shortest doubling time (3 to 5 days) and produced fresh weight (FW), relative growth rate (RGR), crude protein (CP) and crude fibre (CF) at 132.2 g/m2, 0.32 g/g/day, 21.2% DM-1 and 14.4% DM-1, respectively. Furthermore, unprocessed sheep manure (T3) exhibited superior (p < 0.05) fresh weight, relative growth rate, nutrient composition and fibre components compared to the burned manure treatment (T2). In vitro digestibility analysis discovered that T3 achieved a 24-hour accumulated gas production of 86.9 mL DM-1, with in vitro dry matter digestibility (IVDMD), in vitro organic matter digestibility (IVOMD) and metabolisable energy (ME) of 82.9%, 43.7% and 5.8 MJ/kg DM, respectively. These findings suggest that Azolla filiculoides cultivation can be economically optimised using 1.00 g/L unprocessed sheep manure (fresh manure), potentially serving as a self-produced, nutritious feedstuff for ruminants.

An MINLP-based decision-making tool to help microbreweries improve energy efficiency and reduce carbon footprint through retrofits

Microbreweries have greater production costs per litre of beer compared to large breweries, as well as higher carbon footprints. Due to the range of different retrofit technologies available and the different capacities and configurations of microbreweries, it is not always clear what retrofits will improve operations. Therefore, this work proposes a novel mixed-integer nonlinear programming decision-making tool to be used by any microbrewery, that determines the technoeconomic feasibility and sizing of energy efficiency-improving retrofits, including solar and wind power, battery storage, anaerobic digestion, boiler type selection, heat integration by heat storage, and carbon capture via dual-function materials. The model was demonstrated on a real UK microbrewery case study. The model gave an optimal configuration of a 10 m3 anaerobic digester, 30 solar panels outputting 380 W each, an 800 W wind turbine and a 2.3 m3 heat storage tank, reducing annual operating costs by 62.9 % and carbon dioxide emissions by 77.1 % with a payback period of 8 years. The tool is designed to be flexible for use by any microbrewery in any location with any brewing recipe and allow the owner(s) to develop more profitable and sustainable microbreweries.Tweetable abstractMicrobreweries can implement mathematically optimised renewable energy, heat integration and anaerobic digestion to reduce operating costs by 62.9 % and carbon emissions by 77.1 %.

Comparison of the characteristics of small intestinal fluid from white-feathered and yellow-feathered broilers

The objective of this study was to compare the properties of small intestinal fluid (SIF) from white- and yellow-feathered broilers fed variable dietary CP to test the hypothesis that digestive enzymes sourced from the SIF of yellow-feathered broilers could serve as a viable alternative for preparing in vitro SIF specifically for white-feathered broilers. Ten Arbor Acres Plus broilers (32 days of age) and 20 Chinese yellow chickens (51 days of age) were fitted with jejunal cannulas and assigned to dietary treatments as follows: 1) white-feathered broilers (BW of 4.08 ± 0.39 kg) fed diet 1 with CP of 19.88 %, 2) yellow-feathered broilers (BW of 2.89 ± 0.27 kg) fed diet 1, and 3) yellow-feathered broilers (BW of 2.84 ± 0.20 kg) fed diet 2 with CP of 16.32 %. Each treatment contained 10 replicates with 1 broiler in each replicate. Digestive enzyme activities, ion concentrations, pH, 16 amino acid (AA, excluding Tyr and Trp) contents, molecular weight distribution (MWD) of protein, hydrolysis rates on wheat starch, corn starch, casein, and soybean protein concentrate, and in vitro digestible energy of corn, soybean meal, and corn gluten meal were evaluated for SIF. Activities of chymotrypsin and amylase, pH, concentrations (mg/mL) of total amino acid (TAA) and 13 AA (excluding Pro, Cys, and Glu), and hydrolysis rates in casein or soybean protein concentrate were greater (P < 0.05), whereas MWD of protein from 19 to 23 kDa was lower (P < 0.05) in the SIF of yellow compared to white-feathered broilers fed diet 1. Furthermore, activities of chymotrypsin and amylase, concentrations of Na+, and Cl−, MWD of protein from 15 to 18 kDa were greater, while concentrations of K+ were lower in the SIF of yellow-feathered broilers fed diet 2 compared to white feathered broilers fed diet 1. Activities of chymotrypsin and amylase, K+ concentration, pH, TAA and 13 AA (excluding Pro, Cys, and Glu), hydrolysis rates in casein or soybean protein concentrate increased (P < 0.05), while concentrations of Na+ and Cl− (P < 0.05) decreased with dietary CP in SIF from yellow-feathered broilers. This experiment demonstrated diet composition and breed modulate digestive enzyme activities, ions (Na+, K+, Cl−), pH, and AA concentrations in the SIF. Our findings revealed no substantial difference in the hydrolytic characteristics of SIF from white-feathered broilers fed diet 1 and yellow-feathered broilers fed diet 2. Consequently, it is feasible to use digestive enzymes extracted from the SIF of yellow-feathered broilers to prepare simulated SIF for in vitro digestion of white-feathered broilers.

Bioavailability of Supplemented Free Oleanolic Acid and Cyclodextrin-Oleanolic Acid in Growing Pigs, and Effects on Growth Performance, Nutrient Digestibility and Plasma Metabolites.

Oleanolic acid (OLA) has beneficial health effects in animals, but in vivo efficacy in monogastric animals is questioned due to its low bioavailability. To gain further insight on the nutritional effects of OLA it was administered as part of a diet. We investigated digestibility and plasma OLA in pigs and the associated influence on growth, organs, digestibility of nutrients and plasma biochemical profile. Twenty-four crossbred barrows (23.7 ± 1.0 kg BW) were assigned one of three treatments: Control (basal diet without OLA), OLA-1 (basal diet with 260 mg/free OLA) and OLA-2 (basal diet with 260 mg/kg cyclodextrin-OLA). Diets included chromium oxide to estimate digestibility. Blood samples were collected on day 14 for OLA analysis and feces on days 22-24 for determining digestibility. Pigs were slaughtered on day 31 (39.9 ± 2.43 kg BW) and their blood collected for analysis. Growth and organ weights were not affected (p > 0.05). OLA-1 decreased apparent total tract digestibility (ATTD) of energy (p < 0.05). OLA-2 increased ATTD of dry and organic matter compared with Control pigs (p < 0.05). OLA-1 increased plasma calcium and alkaline phosphatase (p < 0.05). Ileal digestibility of OLA was not affected (0.88), although OLA ATTD increased in OLA-1 compared to Control pigs (0.75 vs. 0.82; p < 0.05). OLA-1 and OLA-2 increased plasma OLA compared to Control pigs (p < 0.05 and p = 0.083). In conclusion, although the OLA was digested and absorbed, plasma concentration was low (4.29 µg/L), and pig growth, organs and plasma parameters were not affected.

Digestible energy and nutrient digestibility of full-fat soybean meal in adult and growing guinea pigs

Digestible energy and nutrient digestibility of full-fat soybean meal in adult and growing guinea pigs

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.

Dehydrated Brewery Residue (DBR) can reduce the cost of rabbit production in Brazil, but affects performance, blood nutrients, and carcass characteristics

The study aimed to determine the chemical composition, apparent digestibility of dry matter, energy, and nutrients of Dehydrated Brewery Residue (DBR) for New Zealand White rabbits, as well as evaluate performance, biochemical and immunological blood parameters, carcass characteristics, and meat quality. Two experiments were carried out: digestibility and performance, both in a completely randomized design. In the digestibility experiment, 20 animals of mixed sexes were used, from 45 to 60 days of age, which consumed reference feed (RF) or test feed (TF - 70% RF + 30% DBR). In the performance experiment, 50 mixed-sex animals were used from 31 to 70 days of age. For digestibility, bromatological analyses were made of total dry matter (DM), crude protein (CP), crude fiber (CF), neutral detergent fiber (NDF), acid detergent fiber (ADF), ether extract (EE), mineral matter (MM), organic matter (OM), calcium (Ca), phosphorus (P), gross energy (GE), hemicellulose, cellulose and lignin from samples of feces, feed (RF and TF) and experimental feed (DBR). In terms of performance, the treatments were the basal feed (BF) + four TF, made up of increasing levels of DBR inclusion (10, 20, 30, and 40%). Overall, the apparent digestibility coefficient (ADC) of DM was 64.68 ±7.91%, while the ADC of GE and CP were 67.39 ±7.79% and 80.64 ±8.99%, respectively, resulting in digestible energy and digestible protein contents of 3,081 ±356 kcal/kg and 17.97 ±2.00%. There was a linear reduction (P&lt;0.05) in the final weight, daily weight gain, and daily feed intake, but there was a linear reduction in production costs (P&lt;0.05) for both the 31- to 50-day phase and the 31- to 70-day phase. Circulating levels of calcium (P=0.013) and phosphorus (P=0.019) responded in a linear decreasing pattern to the experimental feeds. The same response was observed for slaughter weight, hot and cold carcass weight, yield of skin, head, commercial cuts, and relative weight of edible organs, as well as meat quality, in which the loss of water on thawing (P=0.004) and shear force (P=0.005) indicated less juiciness and less tenderness in the meat. Levels of 10 to 40% DBR in feed for rabbits from 31 to 70 days of age mitigate production costs, but result in a worsening of performance and reduce circulating levels of calcium and phosphorus, reduce carcass weight, commercial cuts, and edible organs, as well as increasing water loss on thawing, and reducing meat tenderness.

Effect of coated-benzoic acid on growth performance, immunity, and intestinal functions in weaned pigs challenged by enterotoxigenic Escherichia coli.

Benzoic acid (BA) could be added to the diets of weaned pigs to prevent diarrhea due to its antibacterial function. However, BA may be absorbed or decomposed before it can reach the hindgut. This study was conducted to explore the effect of a novel coated benzoic acid (CBA) on growth performance, immunity, and intestinal barrier functions in weaned pigs upon enterotoxigenic Escherichia coli (ETEC) challenge. In a 21d experiment, 32 piglets were randomly assigned to 4 treatments: (1) a basal diet (CON), (2) CON added with CBA at 3 g/kg (CBA); (3) CON and challenged by ETEC (ECON); (4) CON added with CBA at 3 g/kg and challenged by ETEC (ECON). On d 22, all piglets were euthanised to obtain samples. Dietary CBA supplementation elevated the average daily gain (ADG) of the ETEC-challenged pigs (p < 0.05). CBA also improved the digestibility of dry matter, gross energy, and ash (p < 0.05). Moreover, CBA elevated the ratio of blood basophil and the serum concentration of total cholesterol of the ETEC challenged pigs (p < 0.05). Importantly, CBA increased the serum concentrations of immunoglobulin A (IgA), IgG, and IgM (p < 0.05). CBA not only decreased the crypt depth but also increased the ratio of villus height to crypt depth (V:C) in the jejunum and ileum (p < 0.05). Moreover, CBA increased the activities of jejunal and ileal sucrase, and the activities of duodenal and ileal maltase (p < 0.05). Importantly, CBA elevated the expression levels of critical functional genes such as the claudin-1, occluding, glucose transporter-2 (GLUT2), and sodium/glucose cotransporter-1 (SGLT-1) in the jejunal epithelium upon ETEC challenge (p < 0.05). Additionally, CBA increased the abundances of total bacteria and Bacillus, and increased the concentrations of volatile fatty acids (acetic acid, propanoic acid, and butyric acid) in cecum (p < 0.05). These results suggested a beneficial role for CBA in alleviating intestinal injury in weaned pigs following ETEC challenge. Such effects may be tightly associated with elevated immunity and improved intestinal epithelium functions and microbiota.

Socially Acceptable Feed Formulations May Impact the Voluntary Feed Intake and Growth, but Not Robustness of Nile Tilapia (Oreochromis niloticus)

Society is becoming more demanding with aquaculture’s environmental footprint and animal wellbeing. In order to potentially mitigate these concerns, feed formulations could be based on eco-efficient (circular economy-driven) or organic ingredients. This study aimed to investigate the growth performance, feed utilization, and health status of juvenile Nile tilapia (Oreochromis niloticus) when fed with such feeds. The growth trial lasted for 8 weeks, and fish had an initial weight of 31.0 ± 0.5 g (mean ± SD). Fish were fed until visual satiation, in quadruplicate, with one of three isonitrogenous and isoenergetic experimental feeds: a commercial-like feed without fishmeal (PD), a diet based on ingredients compatible with organic certification (ORG), or a feed formulated using circular economy-driven subproducts and emergent ingredients (ECO). Fish fed ECO showed a tendency for decreased feed intake, while ORG fish significantly reduced their intake compared to those fed PD. Consequently, fish fed ECO (62.7 ± 5.4 g) exhibited almost half the growth than those fed PD (107.8 ± 6.1 g), while ORG fish almost did not increase their weight (32.7 ± 1.3 g). ECO and ORG diets had a lower digestibility for protein, lipid, and energy when compared to PD. Feed utilization of fish fed ECO or ORG was also lower than those fed PD. From the health-related genes analyzed, only glutathione reductase (gsr) showed statistically significant differences, being more expressed in fish-fed ECO than those fed PD. Thus, even when such novel formulations induced extreme effects on voluntary feed intake, their impact was noted only in fish growth, but not in robustness.

Interaction of Wheat Bran Particle Size and Stimbiotic Supplementation on Growth Performance and Gut Health Parameters in Broilers.

A 42-day study was conducted with 720-day-old Cobb male broiler chicks allocated to treatments in a 3 × 2 factorial, with the factors as wheat bran (WB) inclusion (no WB, 50 g/kg coarse WB, or 50 g/kg fine WB) and stimbiotic (STB) supplementation in corn-based diets. The inclusion of WB (p < 0.05) or STB supplementation (p < 0.05) increased the FCR and feed intake in the day 0-10 phase. During the day 0-28 phase, coarse-WB inclusion increased (p < 0.05) the FCR, compared to fine WB or diets without WB. In the day 0-42 phase, WB marginally decreased weight gain in diets without STB supplementation, but the STB-supplemented diet, weight gain was greater (p < 0.05) the diet with fine WB compared with diets with coarse WB. Fine-WB inclusion increased the ileal nitrogen and energy digestibility determined at day 18 compared to coarse WB or diets without WB. Supplementation with STB (p < 0.05) or fine WB (p < 0.05) inclusion increased the villi height compared to diets without STB supplementation or coarse WB, or the diet without WB. Coarse or fine WB decreased (p < 0.05) cecal branched-chain fatty acids compared to diets without WB. In conclusion, stimbiotic supplementation to fine WB improved the performance and nutrient digestibility of broilers compared to coarse WB with no effects on the caeca total SCFA concentration.

PSI-26 Effects of particle size and enzyme supplementation on the energy value of field peas fed to growing pigs

Abstract An experiment was conducted to determine if particle size and enzyme supplementation affects the digestible energy (DE), metabolizable energy (ME), and net energy (NE) contents in field peas fed to growing pigs. Male weaned pigs [n = 30; TN70 × TN Tempo; body weight (BW) = 16.5 ± 0.4 kg] were assigned to 1 of 5 dietary treatments: 4 consisting of 50% peas and a corn-soybean meal basal diet. The experiment was carried out as a completely randomized design with treatments arranged in a 2 × 2 factorial design, based on two particle sizes (500μm, 700μm) and two levels of carbohydrase supplementation (0 g/mt, 1,000 g/mt) to give 6 replicates per treatment. Diets were formulated to meet or exceed NRC (2012) requirements. The study was carried out in 3 consecutive periods, each consisting of 15 d; the first 10 d were for adaptation, followed by 5 d of total fecal and urine collection (marker to marker procedure) to calculate DE and ME of diets. The energy content of peas was determined using the difference method. Data were analyzed using the MIXED procedure of SAS. The model included the particle size, enzyme supplementation, and their interaction as a fixed effect. The period was included as a random effect. Least squares means for each treatment were adjusted using Tukey post-hoc test. Dry matter (DM), acid detergent fiber, neutral detergent fiber, gross energy, starch, ash, crude protein, and ether extract contents were analyzed to allow for the prediction of NE content of peas. There were no interactions between particle size and enzyme supplementation on dietary energy values. Also, no main effects of particle size and enzyme supplementation were observed. The average DE, ME, and predicted NE contents for peas were determined to be 3,848, 3,735, and 2,691 kcal/kg DM, respectively. In conclusion, enzyme supplementation and particle size did not influence the DE, ME, and NE contents of the peas.

PSIX-5 Performance of black soldier fly larvae meal as secondary protein sources in extruded dog diets

Abstract Black soldier fly larvae meal (BSFL) has gained market exposure with ties to sustainability and novelty. Graded inclusions of BSFL were assessed for nutrient digestibility, stool quality, and palatability in adult dogs. The BSFL was included at 0%, 5% and 10% in chicken-based extruded dog diets (formulated to 22% crude protein, 13% crude fat, 3% crude fiber). The study was approved by the facility’s Institutional Animal Care and Use Committee. A standard 2-bowl palatability test over a 2-d period was executed (n = 30 dogs each) to determine intake ratios between diets (0% vs. 5%, 0% vs. 10%, and 5% vs. 10%). Total tract nutrient digestibility was evaluated (n = 6 dogs per diet) with 5 d acclimation followed by 5 d total fecal collection. Stool quality was evaluated on a 1 to 5 scale. Palatability data were analyzed using paired t-test. To test for mean differences in digestibility and stool quality outcomes between 0%, 5%, and 10% BSFL dogs, we applied the Kruskal-Wallis test. Statistical significance was set at 5% type 1 error rate. Dry matter, protein, fat, and energy digestibility, and stool quality were similar between all diets (P &amp;gt; 0.05). Palatability was improved (P &amp;lt; 0.05) with inclusion of BSFL (i.e., preference for 5% and 10% vs. 0% inclusion) and improved (P &amp;lt; 0.05) at 10% vs. 5% inclusion. The BSFL tested showed merit as a palatable ingredient source that maintains stool quality and digestibility in adult dogs.

PSII-17 Effect of dietary β-mannanase supplementation on energy and nutrient utilization in diets fed to broiler chickens: A meta-analysis

Abstract Beta-mannan (β-mannan) is a polysaccharide composed of repeating units of mannose, galactose, and glucose. The increased amount of β-mannan is present in various plant protein sources such as soybean meal, palm kernel meal, copra meal, and guar meal. β-mannan is considered an antinutritional factor for non-ruminant animals. Endo-β-mannanase enzymes are endo-hydrolases that can cleave the internal glycosidic bonds of the mannan backbone. As a result, β-mannanase is used to break down β-mannan in animal feeds, thereby aiming to reduce its potential anti-nutritional effects. Previous research has demonstrated that dietary β-mannanase supplementation improves energy and nutrient utilization in broiler diets possibly by decreasing digesta viscosity in the gastrointestinal tract. However, results from previous studies have been inconsistent, mainly due to variable experimental conditions including animals, experimental design, and environment. Meta-analysis is a useful method to comprehensively evaluate and integrate various results from previous studies, thereby providing reliable and practical insights. Therefore, the objective of this study was to conduct the meta-analysis to evaluate the effect of dietary β-mannanase supplementation on digesta viscosity, and energy and nutrient utilization in diets for broiler chickens. Through an extensive literature search conducted on Scopus, PubMed, Web of Science, and Google Scholar between January 2003 and December 2023, we identified 10 eligible studies. The meta-analysis was performed using the “metafor” package in R software version 4.1.3. (R Core Team, 2023), and the standardized mean difference (SMD) and its 95% confidence interval (CI) were calculated using the random effect model. The results revealed that dietary β-mannanase supplementation increased apparent total tract retention (ATTR) of dry matter (SMD = 1.84; 95% CI: 0.46 to 3.21; P = 0.016), gross energy (SMD = 2.16; 95% CI: 1.19 to 3.12; P = 0.001), and nitrogen-corrected apparent metabolizable energy (AMEn) in broiler diets (SMD = 3.38; 95% CI: 1.63 to 5.14; P = 0.002; Table 1). Moreover, dietary β-mannanase supplementation increased apparent ileal digestibility (AID) of gross energy (SMD = 6.65; 95% CI: 3.78 to 9.53; P = 0.002) and nitrogen (SMD = 1.41; 95% CI: 0.55 to 2.27; P = 0.006) in broiler diets (Figures 1 and 2). Finally, digesta viscosity (SMD = -3.35; 95% CI: -4.69 to -2.02; P &amp;lt; 0.001) in broiler chickens was decreased by dietary β-mannanase supplementation. In conclusion, the current meta-analysis indicates that dietary β-mannanase supplementation improves the overall utilization of energy and nutrients in diets with decreasing digesta viscosity in broiler chickens.

PSLBII-30 The effect of different soybean meal batches and protease supplementation on nutrient utilization by broiler chickens

Abstract Soybean meal (SBM) is the major protein source in broiler chicken diets. However, the thermal processing of SBM may have an impact on its protein quality, reducing its solubility when over-processed. In this context, the use of exogenous protease may reduce the negative effects that the over-processing of SBM may have on protein digestibility in broiler chickens. The present study investigated two batches of SBM in broiler chicken diets supplemented or not with protease. One-d-old male Cobb 500 (n = 360) were randomly distributed in a 2 x 2 factorial arrangement (SBM batches: A and B; Protease inclusion: 0 and 50 g/t of diet). SBM protein quality was evaluated through crude protein (CP), KOH solubility, and urease activity test (UA) in batches A and B. Scanning electron microscopy was used to visualize the structural organization of particles from SBM A and B. On d 26, ileal digesta content was collected from 6 broiler chickens that were euthanized to determine the apparent ileal digestibility (AID) of dry matter (DM), crude protein (CP), and ileal digestible energy (IDE). Data obtained were submitted to ANOVA and means were compared by Tukey test with a significance declared of 5% using the GLM procedure on R Software. Protein quality assessment demonstrated KOH solubility of 85% and 75% for SBM from batches A and B, respectively. For UA analysis, SBM batch A presented 0.09 and batch B of 0.01 mg N/g (Table 1). Microscopy images emphasized visual differences in particles from batches A and B. In SBM particles from batch A, disorganized cluster structures and asymmetric pores were observed, whereas in the SBM particles from batch B, insignificant pores and large cluster aggregates were visualized in a denser structure (Figure 1). The SBM batch B presented decreased AID of DM, CP, and IDE (P &amp;lt; 0.05). Protease supplementation improved the AID of CP (P &amp;lt; 0.05) in broilers at 26 d of age, regardless of SBM batches, but no effect was observed for DM and IDE (P &amp;gt; 0.05; Table 2). In conclusion, SBM from batch A had greater values of KOH solubility and UA, suggesting an appropriate thermal process, and ensuring protein quality, which is demonstrated through improvement in nutrient utilization by broiler chickens. The use of 50 g of exogenous protease per t of diet improved the ileal digestibility of CP, regardless of SBM batches.