Net Energy Value Research Articles

Effects of Dietary Protein Levels, Net Energy Levels, and Essential Amino Acid-to-True Protein Ratios on Broiler Performance.

Supplementing essential amino acids (EAAs) without considering non-EAA (NEAA) and energy contents in reduced-crude protein (CP) diets may alter EAA-to-true protein (E:T) and energy-to-protein ratios, potentially compromising growth. This study aimed to evaluate the effects of CP, E:T, and net energy (NE) on broiler performance. The treatments were as follows: T1-reduced CP (16%, RP), low NE (9.9 MJ/kg, LNE), low E:T (0.56, LE:T); T2-RP, LNE, high E:T (0.60, HE:T), with imbalanced EAA (excess Met and deficient Thr); T3-RP, high NE (10.4 MJ/kg, HNE), LE:T; T4-RP, HNE, HE:T; T5-normal CP (18%, NP), LNE, LE:T; T6-NP, LNE, HE:T; T7-NP, HNE, LE:T; and T8-NP, HNE, HE:T. The study employed as-hatched Cobb 500 broilers in two experiments. Exp.1 studied the broiler performance from d19 to 35, with eight replicates per treatment and 16 birds per replicate (n = 1024). Birds were randomly assigned to different treatments, and at the end of their lives, all were dissected to determine their sex and account for any gender-related effects. Exp.2 measured NE values in respiration chambers from d25 to 28, with six replicates per treatment, and two birds (a male and a female) per replicate (n = 96). The bird gender was determined through high-resolution melting curve analysis of feather DNA. The measured NE values were used to calculate NE intake (NEi) in Exp.1. The results showed that T4 improved (p < 0.001) weight gain (WG), feed conversion ratio (FCR), and NEi relative to T1, T2, and T3, and protein efficiency (WG/CP intake) relative to all treatments. The live performance (feed intake, WG, FCR) and NEi of birds fed T4 reached a level equal to those of birds fed NP diets (T5 to T8). These results suggest that a dietary E:T ratio of 0.60 is necessary to maximize nutrient utilization and to restore growth rate in broilers fed RP diets.

Environmental sustainability, energy efficiency and uncertainty analysis of agricultural residue-based bioethanol production: A comprehensive life cycle assessment study

Bioethanol produced from agro-residue provides a sustainable alternative to fossil fuels, mitigating pollution, reducing waste, and promoting a circular economy. However, challenges arise in sustainable sourcing, resource conflicts, water quality concerns, and managing environmental footprints to maximize agro-residue-based bioethanol benefits. The environmental impacts, net energy ratio (NER), net energy value, water footprint, and uncertainties associated with bioethanol production from agro-residues are analyzed in this study. The analysis followed a cradle-to-gate approach using 1 L of bioethanol produced as a functional unit (FU), allowing for a direct comparison of the environmental performance of the different feedstocks. The result shows that rice straw-based bioethanol exhibited higher environmental impacts, particularly in terms of ecotoxicity, ionizing radiation, human toxicity, and ozone layer depletion, except for greenhouse gas emission, which is lowest for corn stover (0.37 kg CO2 eq. per FU) and highest for cassava straw (1.1 kg CO2 eq. per FU). Furthermore, the Cumulative Energy Demand analysis highlighted a significant reliance on fossil fuels from agricultural biomass throughout the bioethanol production process. The energy balance analysis shows that the agricultural residues are feasible for bioethanol production with NER of 1.20, 3.10, and 3.28 for rice straw, corn stover, and cassava straw, respectively. To enhance the accuracy and reliability of the LCA results, Monte Carlo simulation was employed to account for uncertainty and variability in the data. This methodology provides a better understanding of the impacts of bioethanol production, with a focus on sustainability and advancements in reducing our reliance on fossil fuels.

Determination and prediction of the net energy content of wheat bran for pregnant sow

ABSTRACT Two experiments were conducted to determine net energy (NE) values of wheat bran ingredients and develop a prediction equation for NE of wheat bran. In each experiment, 12 multiparous pregnant sows were allocated to two 3 × 6 Youden squares with three consecutive periods and six diets in each square. The study consisted of six diets, including a corn-soybean meal basal diet and five diets formulated with 29.2% wheat bran. Each period lasted for 10 d, with 5 d allocated for adaptation and followed by 5 d for heat production measurement. Sows were provided feed at 604 kJ/kg BW0.75·d−1. On day 10, sows underwent fasting to measure fasting heat production. Results indicated that the inclusion of wheat bran in the diets significantly reduced digestibility of energy and nutrients in (p < 0.05). The average net energy (NE) content of wheat bran was determined to be 8.8 MJ/kg DM. A regress equation NE = 7.968 + 0.28 × CP + 0.607 × EE − 0.782 × ash − 0.05 × hemicellulose (R2 = 0.98, p < 0.01) was found to accurately predit the NE value when feeding pregnant sows with wheat bran-based diets. In conclusion, the net energy content of wheat bran fed to pregnant sows ranged from 7.24 to 10.67 MJ/kg DM and can be effectively estimated using proximate analysis methods.

Improving Heat Efficiency of Aniline Production Process by Modifying Heat Transfer Fluid Looping System in Heating and Cooling Process

The nitrobenzene hydrogenation process is a highly exothermic reaction which causes the product temperature will increase and then needs to be cooled down with a heat exchanger. The modification process is needed to improve the heat efficiency of the nitrobenzene hydrogenation process by utilizing the heat from reactor product. Heat transfer fluid is used as a medium of heat transfer for both heating and cooling, so that will create a looping heat transfer process. The looping system of heat transfer fluid receives heat from reactor product and then reuses the heat to reheat the recycled hydrogen and for other utilities, so additional energy for these processes is not required. The process modification was simulated using Aspen HYSYS and the comparison of heat efficiency between the basic and the modified process is calculated using the net-energy formula. The results obtained that the net-energy (NE) value for both basic and modified process is 96,714,359.832 kJ/h and 9.869 kJ/h. This shows that the modified process has better energy efficiency compared to the basic process as the net-energy value is closer to zero. Therefore, this modification increases the heat efficiency of the aniline production through nitrobenzene hydrogenation process. Copyright © 2024 by Authors, Published by Universitas Diponegoro and BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

EVALUATION OF SILAGE OF SORGHUM AND SUDAN GRASS HYBRID PULP FOR BIOENERGY PURPOSES

This research was carried out to determine the potential for using the pulp of 10 different sorghum x sudan grass hybrid varieties (Aneto, Greengo, Jumbo, Master BMR, Nutri Honey, Nutrima, Sugar Graze II, Supergraze 1000, Süper Su 22, Tonka) used to obtain ethanol in Bingöl, Eastern Anatolian ecological conditions as silage. Field trials were carried out in 3 replications in 2020 according to the randomized block design. The plants were harvested during the pulping period of the grains. The stems from which the sap was extracted were silaged and left for fermentation at room temperature for 45 days. Feed quality characteristics and organic acid contents were determined in silage materials. Depending on the varieties; silages have a physical score of 7-19, dry matter rate 37.58-50.94%, pH value 3.36-4.30, ADF rate 39.33-50.76%, NDF rate 53.40-66.86%, ADL rate 10.90-13.96%, CP rate 2.76-4.46%, DDM ratio 49.33-50.26%, DMI ratio 1.80-2.36%, RFV ratio 68.66-107.00, net energy value 1.176-1.337, AA ratio 0.11-0.66%, BA ratio 0.76-1.16%, LA ratio 0.07-1.05% and PA ratio was found to vary between 0.0013-0.0026%. As a result, it was concluded that silages made with pulp in cultivars of sorghum x sudan grass hybrid plant can be used more appropriately in cellulosic ethanol production than forage.

Energy Balance and Greenhouse Gas (GHG) Emissions of Sesame (Sesamum indicum L.) Production in Türkiye

The objective of this study was to determine the energy use and greenhouse gas emissions associated with sesame production. Energy use efficiency indicators and greenhouse gas emission rates were calculated for the 2022-2023 production season. The energy input and output for sesame production were found to be 12079.15 MJ ha-1 and 30052.44 MJ ha-1, respectively. The study found an energy use efficiency of 2.49, with a specific energy of 12.20 MJ kg-1, an energy productivity of 0.08 kg MJ-1, and a net energy value of 17973.29 MJ ha-1. The direct and indirect energy inputs were calculated to be 4584.41 MJ ha-1 (37.95%) and 7494.74 MJ ha-1 (62.05%), while the renewable and non-renewable energy inputs were calculated to be 469.12 MJ ha-1 (3.88%) and 11610.03 MJ ha-1 (98.65%), respectively. The calculation shows that the total greenhouse gas emissions are 380.52 kgCO2-eq ha-1 and the greenhouse gas emission rate is 0.38 kgCO2-eq ha-1. Sesame production is highly profitable for the 2022-2023 production season in terms of energy use efficiency.

Feeding a Multi-Enzyme Blend to Enhance the Nutrient Digestibility of Wheat-Canola Expeller Diets in Ileal-Cannulated Weaned Pigs.

Canola expeller (CE) contains ~200 g/kg residual oil, but also fiber that impairs nutrient digestibility in weaned pigs. To study if feed enzymes increase digestibility, six diets containing either the basal or two CE samples mixed in at 250 g/kg (CE-A or CE-B) were formulated with or without a multi-enzyme blend containing cellulase, xylanase, glucanase, amylase, protease, invertase, and pectinase. The basal diet containing 620 g/kg wheat and 150 g/kg barley served as control. Twelve ileal-cannulated barrows (9-15 kg) were fed the six diets in a replicated 6 (pigs) × 3 (periods) Youden square. Ileal digestibility of gross energy and amino acids was 5% greater for basal than CE diets without differences between CE samples. Diet energy values were 4% greater for CE than basal diets due to residual oil in CE. Inclusion of the multi-enzyme blend increased total tract digestibility of energy of the basal but not CE diets by 2%. Net energy value was greater for CE-A than CE-B because CE-A contained more residual oil. In conclusion, feeding 250 g/kg CE increased diet energy values; thus, CE can substitute added fat in weaned pig diets. Feeding the multi-enzyme blend increased the energy digestibility of wheat and barley-based diets fed to weaned pigs. However, research is needed to identify enzyme combinations that increase the nutrient digestibility of CE.

Assessing genotypes of buffel grass (Cenchrus ciliaris) as an alternative to maize silage for sheep nutrition.

Nutritive value of five Cenchrus ciliaris (buffel grass) genotypes (IG96-50, IG96-96, IG96-358, IG96-401 and IG96-403) weredetermined. Their sugar contents (>70 mg/g of dry matter) and ensiling potential were evaluated using in vitro batch culture and in vivo studies. Research indicated significant differences (P < 0.05) in the dry matter, organic matter, ether extract, neutral detergent fiber, acid detergent fiber, cellulose and lignin contents of the C. ciliaris genotypes tested. Genotypes also differed (P < 0.05) in total carbohydrates, structural carbohydrates, non-structural carbohydrates and protein fractions. Genotype IG96-96 had the lowest total digestible nutrients, digestible energy and metabolizable energy contents (377.2 g/kg, 6.95 and 5.71 MJ/kg of dry matter, respectively), and net energy values for lactation, maintenance and growth. After 45 days of ensiling, C. ciliaris silages differed (P < 0.05) in dry matter, pH, and lactic acid contents, and their values ranged between 255-339, 4.06-5.17 g/kg of dry matter and 10.8-28.0 g/kg of dry matter, respectively. Maize silage had higher (P < 0.05) Organic Matter (919.5g/kg of dry matter), ether extract (20.4g/kg of dry matter) and hemi-cellulose (272.3 g/kg of dry matter) than IG96-401 and IG96-96 silages. The total carbohydrates and non-structural carbohydrates of maize silage were higher (P < 0.05), while structural carbohydrates were comparable (P < 0.05) with C. ciliaris silages. Sheep on maize silage had (P < 0.05) higher metabolizable energy, lower crude protein, and digestible crude protein intake (g/kg of dry matter) than those on C. ciliaris silage diets. Nitrogen intake and urinary-N excretion were higher (P < 0.05) on genotype IG96-96 silage diet. Overall, this study suggested that certain C. ciliaris genotypes, notably IG96-401 and IG96-96, exhibited nutritive values comparable to maize silage in sheep studies, offering a promising avenue for future exploration as potential alternatives in diversified and sustainable livestock nutrition programs.

172 Effects of post-MSC DDGS inclusion in gestation diets on total tract nutrient and energy digestibility compared with other fiber sources

Abstract The high fiber content of corn dried distiller grains with solubles (DDGS) make it an ideal candidate for inclusion in gestation sow diets. Gestating sows, however, have greater utilization of fibrous ingredients, and nutrient values attained in grower pigs are not representative of nutrient metrics for gestating sows. The objective of this study was to evaluate apparent total tract digestibility (ATTD) of energy and nutrients from post-protein separation (post-MSC) DDGS provided to gestating sows in comparison with soyhulls and sugar beet pulp; two commonly used fiber sources in gestation diets. Pregnant sows [n = 22; parity 0 to 1; initial body weight (BW) = 190 ± 10 kg] were allocated to 1 of 6 dietary treatments in a crossover design with two collection periods (period 1 from d 40-59 of gestation and period 2 from d 60-79 of gestation) to attain at least 7 observations per treatment. Two of the six diets were practical corn-soybean meal-based gestation diets with either soyhulls (17.5% inclusion) or post-MSC DDGS (15% inclusion) to determine ATTD of energy and nutrients in complete diets. The remaining four diets included a corn-basal diet and the basal diet plus 30% inclusion of post-MSC DDGS, soyhulls, or sugar beet pulp. Titanium dioxide was included as an indigestible marker to calculate ATTD. Sows were fed experimental diets (2.2 kg/d in a single feeding) in two 20-d collection periods where the initial 14 d considered a diet adaptation period followed by 5 d for total collection of urine (collected using urine catheters inserted on d 14) and grab fecal samples. Energy values for the post-MSC DDGS, soyhulls, and sugar beet pulp in the corn-basal diets were calculated using differential procedure. Data were analyzed with ANOVA and fixed to a mixed linear model using treatment as the main effect and collection period as a random variable. The ATTD of the post-MSC DDGS practical diet was 8% greater in ATTD of crude protein and 13% greater in ATTD of ether extract than the practical soyhull diet (P &amp;lt; 0.01). The ATTD of gross energy of post-MSC DDGS was 16% greater than soyhulls (P &amp;lt; 0.01). This resulted in an 800 and 750 kcal/kg greater digestible energy and metabolizable energy content, respectively on an as-fed basis in post-MSC DDGS compared with soyhulls and sugar beet pulp (P &amp;lt; 0.01). The post-MSC DDGS also had a net energy value (as-fed basis) 700 kcal/kg greater than soyhulls and sugar beet pulp. In conclusion, post-MSC DDGS is suitable for inclusion in gestating sow diets as a fiber source while meeting the energy needs of the gestating sow.

106 Net energy of soybean meal

Abstract Our current net energy (NE) systems were developed based on work conducted around 40 yr ago. At that time, it was normal that pigs deposited no more than 40% of the protein they were fed. However, modern genetic lines are much leaner than older genetics and they deposit more protein than earlier. It is, therefore, not uncommon that protein deposition in modern genotypes exceeds 60% of dietary protein intake. This means that more of the amino acids in the protein-rich ingredients are used for protein deposition and less are being deaminated with a subsequent reduced energetic cost of deamination associated with feeding protein-rich ingredients. As a consequence, the theoretical energy value of protein rich ingredients such as soybean meal (SBM) is greater when fed to modern pigs than to older genotypes that were used when our current NE systems were developed. Indeed, in several recent experiments it was demonstrated that the ME and NE of SBM is greater than indicated in current feed ingredient tables. A greater NE than predicted has also been demonstrated for field peas, whereas corn does not seem to have increased energy value compared with previous estimates, which is consistent with the hypothesis that it is the increased protein efficiency of modern pigs that is the reason for the greater NE value in SBM. As a consequence of the greater NE value of SBM, less added fat need to be used to reach a certain NE level in the diet, which will reduce overall diet costs. However, because of the greater genetic capacity for protein deposition in modern pigs, there is a need to upgrade the NE system and to develop new equations to predict NE in diets and ingredients based on the protein deposition capacity of modern pigs. It can also be argued that because commercially fed pigs always are group housed and allowed ad libitum intake of feed, pigs fed to generate prediction equations for NE also need to be group housed and allowed ad libitum intake of feed because both animal behavior and level of feed intake may affect the NE value of diets. In conclusion, because of the increased ability of modern genotypes of pigs to retain dietary protein in the body, there is reduced deamination of amino acids and therefore reduced energy loss in modern pigs than in older genotypes, which results in greater NE of protein rich ingredients including SBM. There is, therefore, a need for developing a new NE system that preferably uses group-housed pigs that are allowed ad libitum access to feed.

60 Effects of phase feeding rolled hybrid rye on feedlot performance in backgrounded beef steers

Abstract The objective of this study was to evaluate the effects of phase-fed rolled hybrid rye on feedlot performance and carcass characteristics of finishing steers. Backgrounded steers [n = 110; initial shrunk (4% of body weight; BW) = 391 ± 1.3 kg] were assigned to 1 of 14 pens at the Southeast Research Farm, Beresford, SD in a randomized complete block design. Pens were blocked by location with four blocks of dirt-surfaced, outside pens (8 pens; 10 steers/pen) and three blocks of concrete-surfaced, partially covered pens (6 pens; 5 steers/pen). Pens were randomly assigned to one of two dietary treatments (7 pens/treatment): dry rolled corn (DRC) included at 66% diet dry matter (DM) or rolled hybrid rye (RRYE) included at 66% diet DM for the initial 46 d of the experiment followed by the DRC diet from d 47 to trial completion on d 144. One steer was removed from the study because of lameness. During the rye feeding period (d1 to d 46), RRYE decreased average daily gain (ADG) by 13% (P = 0.01; 1.59 and 1.83 kg, respectively) and DMI by 18% (P = 0.01; 8.45 and 10.30 kg, respectively) with no effect (P = 0.15) on gain to feed ratio (G:F) compared with DRC. Negative effects of RRYE were more pronounced during the first 20 d of the experiment with ADG reduced by 29% (P = 0.01; 1.13 and 1.60 kg, respectively), DMI by 15% (P = 0.01; 8.20 and 9.61 kg, respectively), and G:F by 17% (P = 0.01; 0.139 and 0.167, respectively). Dietary net energy values for RRYE were increased (P ≤ 0.03) from d 1 to 46. Feeding rye reduced BW on d 46 by 10 kg compared with DRC (P = 0.01; 474 and 464 kg, respectively). From d 47 to 144 when all steers were fed a common diet there were no differences (P ≥ 0.38) in any growth performance responses or measures of dietary net energy utilization. When measured over the entire experiment, DMI tended to be less (P = 0.08) for RRYE compared with DRC with no effect on ADG or G:F (P ≥ 0.19). Final BW was numerically reduced in the RRYE treatment compared with DRC (P = 0.21; 614 and 623 kg, respectively). Cumulative observed-to-expected ratios for NEm and NEg were increased (P = 0.05) for RRYE compared with DRC. Dietary treatments did not affect (P ≥ 0.29) carcass characteristics, distribution of USDA yield or quality grades, or liver abscess incidence or severity. Feeding rolled rye decreased ADG, DMI, and G:F during the first 46 DOF with similar growth performance when fed a DRC-based diet for the final 98 d.

103 Effects of partial or total replacement of dried distiller’s grain with soybean meal on growth performance, carcass characteristics, sera urea nitrogen, and net energy utilization in finishing beef steers

Abstract The objective of this study was to determine if partial or complete replacement of dried distiller’s grains plus solubles (DDGS) with solvent-extracted soybean meal (SBM) influences growth performance, efficiency of dietary net energy utilization, sera urea-N (SUN) concentrations, or carcass traits in finishing beef steers. Continental × British steers [initial shrunk body weight (BW) = 382 ± 37 kg] were used in a 139-d experiment. Treatments included: DDGS fed at 20% DM (13.4% CP; DDGS), SBM replacing 50% of DDGS (14.4% CP; SBM50), and SBM replacing 100% of DDGS (15.4% CP; SBM100). Steers (n = 189) were weighed and allotted to 1 of 24 pens (n = 8 steers per pen; 8 pens per treatment) at the Ruminant Nutrition Center near Brookings, SD. Whole blood was collected and harvested as sera on d 77, 105, and 139 to determine SUN concentration. Growth and carcass data were analyzed as a randomized complete block design using the GLIMMIX procedure of SAS 9.4 with treatment and block (initial BW grouping) as fixed effects; SUN data were analyzed using repeated measures, pen was the experimental unit. Inclusion level was evaluated for linear and quadratic components by the method of orthogonal polynomials. Final BW was calculated by dividing hot carcass weight (HCW) by 0.625. No differences were noted (P ≥ 0.18) for final BW, average daily gain, dry matter intake, or feed efficiency. Dietary treatment tended to affect gain to feed ratio (G:F; quadratic; P = 0.10) and SBM increased the apparent efficiency of energy capture. Treatment had no effect (P ≥ 0.22) on HCW, rib fat, marbling score, USDA yield grade, or final BW adjusted to 28% empty body fat. Complete replacement of DDGS with SBM increased rib eye area by 1% (linear; P = 0.02), but decreased dressing percentage (linear, P = 0.03). Distribution of USDA quality or yield grades were unaffected by treatment (P ≥ 0.36). No treatment × day interaction was observed for SUN (P = 0.20). However, day (P &amp;lt; 0.01) and treatment (P &amp;lt; 0.01) effects were observed. Initial samples (d 77) differed between DDGS and SBM treatments, with the latter having greater SUN values (P &amp;lt; 0.01). On d 105, the SBM100 treatment had greater SUN than DDGS, and SBM50 was intermediate (P &amp;lt; 0.01). On d 139, steers from SBM100 had elevated increased SUN compared with SBM50 and DDGS treatments (P &amp;lt; 0.01). Net energy values calculated from animal performance for DDGS agreed closely with tabular estimates. In this experiment, replacement of DDGS with SBM increased the observed to expected ratio of dietary NE, increased muscularity and tended to decrease DP with no other observed effects on growth performance or carcass traits.

26 Effects of increasing net energy or standardized ileal digestible lysine in soybean meal-based diets on early and late finishing pig performance

Abstract A total of 2,265 finishing pigs [337×1050, PIC; initial body weight (BW) = 50.2 kg) were used in two 28-d trials to determine the effect of increasing net energy (NE) or standardized ileal digestible Lys in soybean meal (SBM) based diets on early and late finishing pig performance. There were 27 pigs/pen and 21 pens/treatment. Soybean meal NE value used in diet formulation was either 78% (2,087 kcal/kg) or 100% (2,672 kcal/kg) of corn NE. Four treatment diets were assigned to pens in a completely randomized design and consisted of: 1) high level of SBM estimated at 100% NE of corn (High SBM); 2) low level of SBM estimated at 100% NE of corn with added feed-grade AA (Low SBM); 3) low level of SBM estimated at 78% NE of corn with added fat (Low SBM w/fat) to equal the NE in diets 1 and 2; and 4) low level of SBM estimated at 100% NE of corn with increased feed-grade AA and increased Lys:NE (Low SBM w/AA). Following the early finishing 28-d growth trial (initial BW = 50.2 kg), pigs were fed a common diet for 30-d and pens were randomly reallotted to 1 of the same 4 treatments for the late finishing trial (initial BW 114.1 kg). In early finishing, there were no differences (P &amp;gt; 0.10) in average daily gain (ADG), but pigs fed Low SBM w/AA had increased (P &amp;lt; 0.05) average daily feed intake (ADFI) compared with pigs fed High SBM (Table). The increased ADFI without increased ADG resulted in decreased (P &amp;lt; 0.05) gain to feed ratio (G:F) in pigs fed Low SBM w/AA compared with pigs fed Low SBM w/fat. Pigs fed Low SBM w/fat had improved (P &amp;lt; 0.05) caloric efficiency (CE) compared with pigs fed Low SBM w/AA. In late finishing, there was a tendency (P = 0.099) for a treatment effect on G:F where pigs fed High SBM had the greatest G:F, but there was not a significant difference (P &amp;gt; 0.05) between any two treatments when using a Tukey multiple comparison adjustment. There was no evidence (P &amp;gt; 0.10) for a difference between treatments on ADG, ADFI, or CE. Based on the performance of pigs fed the Low SBM w/AA diet, the decreased growth performance of low SBM diets is not due to a low Lys:Calorie ratio that results when NE is underestimated. Using caloric efficiency, an estimate of the NE of SBM was calculated by adjusting NE of SBM used in formulation until CE for the High SBM and Low SBM treatments were equal. These results showed SBM was estimated to contain 94% the NE of corn in the early finishing period and 125% the NE of corn in the late finishing period.

107 Soybean meal energy value under field conditions: Where are we at and where are we going?

Abstract Soybean meal (SBM) is the main protein source for swine diets globally. Considering its wide utilization and relevance to the swine industry, it is critical to accurately characterize its nutritional profile. The net energy (NE) of SBM has been particularly scrutinized as an increasing amount of evidence suggests it may be underestimated. For instance, the NRC (2012) reports the NE of SBM as 2,087 kcal/kg. Recent indirect calorimetry trials suggest, however, that this value could be at least 8% greater. Furthermore, large scale growth assays conducted under the rigors and challenges of field conditions indicate that the energy of SBM may be even greater. The foundation of such growth assays is to relate the energy value of a test ingredient, in this case SBM, to the energy value of a known ingredient it replaces in diet formulation, such as corn. Changes in feed and caloric efficiencies are measured and can then be used to estimate the energy content of SBM relative to corn. Multiple field trials established that when fed increasing levels of SBM, late nursery, growing, and finishing pigs respond with linear improvements in feed and caloric efficiencies, suggesting an underestimation of the energy value of SBM. In those cases, while the NRC value for SBM NE is 78% of corn NE, this value ranges from 100 to 125% under field conditions. It is hypothesized that the discrepancy between NE values derived from academic and commercial facilities could be driven by differences in health and environmental conditions and the functional molecules within SBM. These functional molecules, such as isoflavones and saponins, have been reported to exert anti-inflammatory, anti-viral, and antioxidant properties. In a challenging field environment, such molecules could bolster the immune response, consequently conserving and redirecting energy from the immune system to growth. Although the evidence is robust, it is critical to understand the particularities of such trials. The methodology utilized is clearly not the same as classic NE measurements. Thus, the term productive energy has been proposed to describe the energy value observed in growth assays. Although all studies agree that the energy of SBM should be greater than traditional publications, there is significant variability across studies which should be further investigated. Nevertheless, these findings provide important insight regarding the value of SBM, particularly for practical swine nutritionists.

Broiler Age Differently Affects Apparent Metabolizable Energy and Net Energy of Expanded Soybean Meal.

Accurately determining the energy values of ingredients is crucial for meeting energy requirements and achieving maximum production performance of animals. This study was conducted to measure the available energy values of three expanded soybean meals (ESBMs) for Arbor Acres male broilers from 14 to 16 day and 28 to 30 day using the difference method. A corn-soybean basal diet was formulated, and test diets were developed with 25% ESBMs as substitutes for energy-yielding ingredients. A completely randomized design was used for determining heat production and energy balance of broilers in 12 open-circuit respiration chambers, with six replicates per group. Prior to measurement, four (14 to 16 day) or two (28 to 30 day) birds per chamber were given a 4-day adaption to diets and chambers. The period lasted for 3 days to determine the apparent metabolizable energy (AME), nitrogen balance, gas exchanges, and heat production. Broilers fed test diets with 25% ESBM exhibited higher nitrogen intake (p < 0.05), nitrogen excreta (p < 0.05), and increased energy deposition as protein irrespective of age (p < 0.05). Furthermore, results showed that AME, nitrogen corrected AME (AMEn), and net energy (NE) values of 3 ESBMs averaged 10.48, 8.93, and 6.88 MJ/kg for broilers from 14 to 16 day, while averaged 11.91, 10.42, and 6.43 MJ/kg for broilers from 28 to 30 day. Broilers from 28 to 30 day showed significantly higher AMEn values but lower NE/AME values of ESBMs compared with those from 14 to 16 day (p < 0.05). Therefore, age-dependent energy values of a single ingredient should be considered in feed formulations to optimize economic returns.

Exploring odontocete depredation rates in a pelagic longline fishery.

Several odontocete species depredate catch and bait from fishing gear, resulting in their bycatch and causing substantial economic costs. There are no known mitigation methods for odontocete depredation in pelagic longline fisheries that are effective, do not harm odontocetes and are commercially viable. Understanding odontocetes' depredation strategies can contribute to mitigating this human-wildlife conflict. Using observer data from the Hawaii-based tuna longline fishery, this study summarized teleost and elasmobranch species-specific mean posterior odontocete depredation rates using a simple Bayesian binomial likelihood estimator with a Bayes-Laplace prior. Depredation rates of species with sufficient sample sizes ranged from a high of 1.2% (1.1 to 1.3 95% highest posterior density interval or HDI) for shortbill spearfish to a low of 0.002% (0.001 to 0.003 95% HDI) for blue shark. Depredation of catch is a rare event in this fishery, occurring in about 6% of sets. When depredation did occur, most frequently odontocetes depredated a small proportion of the catch, however, there was large variability in depredation rates between teleost species. For example, bigeye tuna was two times more likely to be depredated than yellowfin tuna (odds ratio = 2.03, 95% CI: 1.8-2.3, P<0.0001). For sets with depredation, 10% and 2% of sets had depredation of over half of the captured bigeye tuna and combined teleosts, respectively. All elasmobranch species had relatively low depredation rates, where only 7 of almost 0.5M captured elasmobranchs were depredated. Odontocetes selectively depredate a subset of the teleost species captured within sets, possibly based on net energy value, chemical, visual, acoustic and textural characteristics and body size, but not median length, which was found to be unrelated to depredation rate (Pearson's r = 0.14, 95% CI: -0.26 to 0.50, p = 0.49). Study findings provide evidence to support the identification and innovation of effective and commercially viable methods to mitigate odontocete depredation and bycatch.

In silico and in vitro prediction of new synthesized N-heterocyclic compounds as anti-SARS-CoV-2

Computer-aided drug design has been employed to get the medicinal effects against Corona virus from different pyridine derivatives after synthesizing the new compounds. Additionally, various computational studies are also employed between the newly prepared pyridine derivatives and three controls against three proteins (6Y2E, 6M71 and 6M3M). Different methods were employed to synthesize new pyridine derivatives according to the literature using different reaction mediums. MTT was performed for cytotoxicity study and IC50 for inhibitory concentration. Additionally, in-silico studies including DFT, molecular docking, molecular dynamics, MMPBSA, ADME, pharmacokinetics and Lipinski rules were evaluated. The chemical structures of all new compounds were elucidated based on spectroscopic investigation. A molecular docking study demonstrated that compounds 5, 11, and 12 have the best binders of the SARS-CoV-2 main protease enzyme, with energy scores of − 7.5 kcal/mol, − 7.2 kcal/mol, and − 7.9 kcal/mol, respectively. The net binding energy values of the 11-Mpro, 12-Mpro, and 5-Mpro complexes revealed their highly stable nature in terms of both intermolecular interactions and docked conformation across the simulation time. ADME properties, besides the pharmacokinetics and Lipinski rules, showed that all seven newly synthesized compounds follow Lipinski rules with high GI absorption. The In Vitro antiviral study against SARS-CoV-2 using MTT methods confirms that compound 5 has more potential and is safer than other tested compounds. The study shows that the newly synthesized pyridine derivatives have medicinal properties against SARS-CoV-2 without violating Lipinski rules. Compounds 5, 11, and 12, particularly compound 5, may serve as promising potential candidate for COVID-19.

Influence of metabolizable protein and methionine supplementation on growth-performance of Holstein steer calves during the initial 112-d feedlot growing phase.

The objective was to examine the effects of metabolizable protein (MP) and ruminal-protected methionine supplementation on growth performance of Holstein steer calves during the initial feedlot growing phase (112 d). One hundred eighty Holstein steer calves (122 ± 7kg) were blocked by weight and assigned to 30 pens (6 steers per pen). Five treatments were applied: 1) control, a diet based on steam-flaked corn containing urea and dry distillers grains plus solubles as supplemental N sources with no amino acid addition; 2) control diet plus blood meal supplementation; 3) diet from treatment 2, with 0.064% Smartamine M (70% methionine; Adisseo, Alpharetta, GA) supplementation; 4) diet from treatment 2 with 0.096% Smartamine M supplementation; 5) diet from treatment 2 with 0.128% Smartamine M supplementation. All diets were formulated to exceed the estimated MP requirements. The estimated metabolizable lysine, as well as methionine, was deficient in the control diet. Blood meal was added to the control diet to meet estimated lysine requirements (diet 2), the other diets had increasing concentrations of supplemental methionine. Supplemental MP enhanced (10%, P < 0.02) interim and overall 112-d average daily gain (ADG). Additional effects of supplemental methionine on ADG were not appreciable (P > 0.10). Supplemental MP did not affect (P > 0.10) dry matter intake (DMI) during the first 56-d period; however, it tended to increase (P = 0.08) DMI during the subsequent 56-d period. Overall, supplemental MP or methionine had no appreciable effect (P > 0.10) on DMI. Supplemental MP improved (P < 0.01) gain efficiency and estimated dietary net energy (NE) values during the initial 56-d period (11 and 7%, respectively) and overall (7 and 4%, respectively). Supplemental MP did not affect (P > 0.10) gain efficiency during the second 56-d period, although it tended to enhance (P = 0.08) estimated dietary NE. Supplemental methionine did not appreciably affect (P > 0.10) gain efficiency or estimated dietary NE. Therefore, adding MP to cover the estimated limiting amino acid supply in diets may enhance the gain efficiency and dietary energetics of growing Holstein calves. However, amino acid addition supplementation beyond the requirements may not produce extra productive performance of steer calves.

Prediction of net energy of feeds for broiler chickens

Net energy (NE) enables the prediction of more accurate feed energy values by taking into account the heat increment which is approximately 25% of apparent metabolizable energy (AME) in poultry. Nevertheless, application of NE in poultry industry has not been practiced widely. To predict the NE values of broiler diets, 23 diets were prepared by using 13 major ingredients (wheat, corn, paddy rice, broken rice, cassava pellets, full-fat soybean, soybean meal, canola meal, animal protein, rice bran, wheat bran, palm kernel meal and palm kernel oil). The diets were formulated in order to meet the birds' requirements and get a wide range of chemical compositions (on DM basis; 33.6% to 55.3% for starch; 20.8% to 28.4% for CP, 2.7% to 10.6% for ether extract [EE] and 7.0% to 17.2% for NDF), with low correlations between these nutrients and low correlations between the inclusion levels of ingredients allowing for the calculation of robust prediction equations of energy values of diets or ingredients. These diets were fed to Ross 308 broilers raised in 12 open-circuit respiratory chambers from 18 to 23 d of age (4 birds per cage) and growth performance, diet AME content and heat production were measured, and dietary NE values were calculated. The trial was conducted on a weekly basis with 12 diets measured each week (1 per chamber), 1 of the 23 diets (reference diet) being measured each week. Each diet was tested at least 8 times. In total, 235 energy balance data values were available for the final calculations. Growth performance, AME (15.3 MJ/kg DM on average) and AME/GE (79.4% on average) values were as expected. The NE/AME value averaged 76.6% and was negatively influenced by CP and NDF and positively by EE in connection with efficiencies of AME provided by CP, EE and starch for NE of 73%, 87% and 81%, respectively. The best prediction equation was: NE = (0.815 × AME) – (0.026 × CP) + (0.020 × EE) – (0.024 × NDF) with NE and AME as MJ/kg DM, and CP, EE and NDF as % of DM. The NE prediction equations from this study agree with other recently reported equations in poultry and are suitable for both ingredients and complete feeds.

Effect of Supplementing a Bacillus Multi-Strain Probiotic to a Post-Weaning Diet on Nutrient Utilisation and Nitrogen Retention of Piglets

Probiotics are suggested to improve pig health, nutrient utilisation, performance, and they may reduce nitrogen (N) pollution. However, the effectivity of a single strain might be different from that of a multi-strain. The study was conducted to investigate the effect of a novel Bacillus multi-strain on nutrient digestibility, energy utilisation, and N retention in weaned piglets using an European diet. The experiment consisted of a control diet (CD) and a supplemented diet (SD). The probiotic used for SD consisted of B. amyloliquefaciens—516 and B. subtilis—541. A total of eight boars/treatment were weaned (day 0; 8.5 kg body weight). Only boars were used to ease the collection of urine. Until day 10, piglets were fed ad libitum and were housed in pairs; from day 11, piglets were fed semi ad libitum (feeding level 3.2× metabolic body weight) and were housed individually. From day 14, faecal and urine were collected twice daily. Piglets were humanely euthanised at day 19 (15.0 kg bodyweight) after which the jejunum, ileum, and colon content were collected. In faeces, the apparent total tract digestibility (ATTD) of, amongst others, DM, organic matter (OM), crude protein (CP), non-starch polysaccharides (NSP), and subsequently net energy (NE) were calculated using titanium dioxide as an indigestible marker. In the jejunum and ileum, the apparent digestibility of CP was estimated, and in the ileum, the apparent AA digestibility was measured. In urine, the N content was measured to determine N retention. The volatile fatty acid (VFA), branched-chain fatty acid (BCFA), and lactic acid content were analysed in the colon and faeces. The apparent CP digestibility in the jejunum and ileum was not affected by treatment (p &gt; 0.05), and no effect was observed on the apparent ileal digestibility of AA (p &gt; 0.05). Supplementation with the multi-strain probiotic improved the ATTD of DM (p = 0.01; +1.3%) and OM (p = 0.02; +1.2%) and tended to improve the ATTD of CP (p = 0.10; +2.2%) and NSP (p = 0.07; +1.9%). The multi-strain probiotic also improved the NE value (p = 0.02; +0.2 MJ/kg DM) and improved N retention (p = 0.05; +1.6%). Supplementation did not influence the VFA, BCFA, and lactic acid content in the faeces (p &gt; 0.05). However, in the colon, supplementation did influence the lactic acid content (lower; p = 0.01) and tended to influence the valeric acid content (higher; p = 0.09). In conclusion, results from the current study suggest that the multi-strain probiotic has the potential to contribute to improve nutrient efficiency in weaned piglets. More research needs to be conducted to identify the impact of the improved nutrient utilisation on gut health in post-weaned pigs as well as environmental pollution.