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Objective The present study aimed to measure fecal and urinary phosphorus (P) excretion from pigs and to develop prediction models for P excretion of pigs. Methods A total of 96 values for P excretions were obtained from pigs of 15 to 93 kg body weight (BW) fed 12 diets in four experiments and were used to develop the prediction models. All experimental diets contained exogenous phytase at 500 phytase units per kg. Body weight of pigs and dietary P concentrations were used as independent variables in the prediction models. Results The BW, feed intake, and P intake were positively correlated with total (fecal plus urinary) P excretions (r = 0.80, 0.91, and 0.94, respectively; p

The present work aimed to assess the nutrient digestibility of soybean meal (SBM) products based on in vitro procedures. Two-step and three-step in vitro assays were performed to mimic the digestion and absorption of nutrients in the digestive tracts of growing swine. The two-step in vitro method was modified to reflect the digesta retention time and digestive enzymes of nursery piglets by decreasing incubation periods and digestive enzymes to half of those in the procedure for growing pigs and was used to determine the crude protein (CP) digestibility of nursery piglets. The seven ingredients included conventional SBM, thermo-mechanically processed SBM (TSBM), and five sources of fermented SBM (FSBM). The five sources of FSBM were produced using different microorganisms for fermentation, namely: (1) Pediococcus pentosaceus and Bacillus subtilis, (2) Enterococcus faecium (FSBM-EF), (3) Aspergillus oryzae and Bacillus subtilis, (4) Aspergillus oryzae, and (5) Bacillus licheniformis. Based on the conventional procedure, the in vitro ileal disappearance of CP in TSBM was greater (p < 0.05) compared with that in FSBM sources. Based on the in vitro assays for total tract digestibility, organic matter in TSBM was better digested (p < 0.05) compared with that in FSBM except for FSBM-EF. Based on the in vitro procedure for nursery piglets, the ileal disappearance of CP in TSBM was greater (p < 0.05) than that in the other SBM products. Taken together, thermo-mechanical processing rather than microbial fermentation of SBM improves the nutrient digestibility of SBM, particularly in nursery pigs.

The objectives were to determine the effects of graded inclusion rates of wheat bran (WB) on apparent ileal (AID), apparent total tract (ATTD), and hindgut digestibility of nutrients and tested the influence of ileal digesta collection on proceeding fecal nutrient digestibility in pigs. Six barrows with an initial mean body weight of 70.7 ± 5.7 kg fitted with an ileal T-cannula were used. The animals were assigned to a replicated 3 × 3 Latin square design with three diets and three periods. A basal diet was based mainly on wheat, soybean meal, and cornstarch. Two additional diets were formulated to contain 20 or 40% of WB at the expense of cornstarch. Each experimental period consisted of a seven-day adaptation period and a four-day collection period. After the adaptation period, fecal samples were collected on day 8, and ileal digesta were collected on days 9 and 10. Another set of fecal samples was collected on day 11 to determine the influence of ileal digesta collection on proceeding total tract nutrient digestibility. The AID of energy, dry matter (DM), organic matter (OM), crude protein, and phosphorus linearly decreased (p < 0.05) with an increasing inclusion rate of WB from 0 to 40%. The ATTD of energy, DM, OM, crude protein, ether extract, and phosphorus linearly decreased (p < 0.01) as the inclusion rate of WB increased. Hindgut digestibility of DM, OM, and ether extract linearly increased (p < 0.05) with an increasing inclusion rate of WB. The ATTD of GE and most nutrients did not differ between the two fecal collection periods of before and after ileal digesta collection. Taken together, the inclusion of a fiber-rich ingredient reduced ileal and fecal digestibility of nutrients but increased hindgut digestibility of some nutrients, and total tract digestibility of nutrients did not differ whether the fecal samples were collected before or after two days of ileal digesta collection in pigs.

The objective was to determine the effects of drying and blanching methods on the nutrient utilization of black soldier fly larva (BSFL; Hermetia illucens) meal by pigs using in vitro assays. Two-step and three-step in vitro assays were employed to simulate the gastrointestinal tract of pigs. Four BSFL meals were prepared using the following pretreatment methods: (1) microwave drying at 80 °C for 32 min, (2) hot-air drying at 60 °C for 17 h, (3) blanching for 5 min in boiling water and hot-air drying at 60 °C for 17 h, and (4) 2% citric acid solution blanching for 5 min in boiling solution and hot-air drying at 60 °C for 17 h. After the drying process, each BSFL was defatted and ground to obtain BSFL meals. The nitrogen (N) concentration in the test ingredients ranged from 8.5 to 9.4%, and the ether extract ranged from 6.9 to 11.5% on an as-is basis. The amino acid (AA) concentration in the BSFL meals ranged from 2.80 to 3.24% for Lys and 0.71 to 0.89% for Met on an as-is basis. Hot-air-dried BSFL meal had a greater in vitro ileal disappearance (IVID) of N compared with microwave-dried BSFL meal (p < 0.05). However, blanched BSFL meals in water or 2% citric acid solution before hot-air drying had a lower (p < 0.05) IVID of N compared with microwave-dried or hot-air-dried BSFL meal. Blanched BSFL meals in water or 2% citric acid solution before hot-air drying showed a lower (p < 0.05) in vitro total tract disappearance of dry matter and organic matter compared with microwave-dried or hot-air-dried BSFL meal. Microwave-dried BSFL meal had a lower (p < 0.05) IVID of indispensable AA, except for His, Lys, Met, and Phe, compared with hot-air-dried BSFL meals. However, blanched BSFL meals in water or 2% citric acid solution before hot-air drying showed a lower (p < 0.05) IVID of indispensable AA compared with microwave-dried or hot-air-dried BSFL meal. In conclusion, hot-air-dried BSFL meal presented greater nutrient utilization compared with microwave-dried BSFL meal for pigs. However, blanching in water or citric acid solution negatively affected the nutrient digestibility of BSFL meal based on in vitro assays.

Abstract This study investigates the potential of a multi-TeV Muon Collider (MuC) for probing the Inert Triplet Model (ITM), which introduces a triplet scalar field with hypercharge Y = 0 to the Standard Model. The ITM stands out as a compelling Beyond the Standard Model scenario, featuring a neutral triplet T 0 and charged triplets T ± . Notably, T 0 is posited as a dark matter (DM) candidate, being odd under a Z 2 symmetry. Rigorous evaluations against theoretical, collider, and DM experimental constraints corner the triplet scalar mass to a narrow TeV-scale region, within which three benchmark points are identified, with T ± masses of 1.21 TeV, 1.68 TeV, and 3.86 TeV, for the collider study. The ITM’s unique TTVV four-point vertex, differing from fermionic DM models, facilitates efficient pair production through Vector Boson Fusion (VBF). This characteristic positions the MuC as an ideal platform for exploring the ITM, particularly due to the enhanced VBF cross-sections at high collision energies. To address the challenge of the soft decay products of T ± resulting from the narrow mass gap between T ± and T 0, we propose using Disappearing Charged Tracks (DCTs) from T ± and Forward muons as key signatures. We provide event counts for these signatures at MuC energies of 6 TeV and 10 TeV, with respective luminosities of 4 ab−1 and 10 ab−1. Despite the challenge of beam-induced backgrounds contaminating the signal, we demonstrate that our proposed final states enable the MuC to achieve a 5σ discovery for the identified benchmark points, particularly highlighting the effectiveness of the final state with one DCT and one Forward muon.

Abstract The light fermiophobic Higgs boson h f in the type-I two-Higgs-doublet model can evade the current search programs at the LHC since its production through the quark-antiquark annihilation and gluon fusion is not feasible. The particle can be more elusive if the model retains stability up to the Planck scale because the efficient discovery channels are missing from the existing search chart. Through the comprehensive scanning, we show that all the viable parameter points with the Planck cutoff scale require m h f ∈ $$ {m}_{h_f}\in $$ [80, 120] GeV and M A / H ± ∈ $$ {M}_{A/{H}^{\pm }}\in $$ [90, 150] GeV. Since h f h f → γγW + W − and H ± → τ ± ν/h f W ± are dominant in this case, two final states are more efficient to probe h f than the conventional search mode of 4γ + W ± /Z. One is τ ± νγγ from pp → H ± (→ τ ± ν)h f(→ γγ) and the other is (ℓ ± = e ± , μ ± ) from pp → H ± (→ h f W ± )h f → γγW + W − W ± , pp → H ± (→ h f W ± )A(→ h f Z) → γγW + W − W ± Z, and pp → H +(→ h f W +)H − (→ h f W − ) → γγW + W − W + W − . The inclusive consists of a same-sign dilepton, two prompt photons, and missing transverse energy. We perform the signal-background analysis at the detector level. With the total integrated luminosity of 300 fb −1 and the 5% background uncertainty, two proposed channels at the 14 TeV LHC yield signal significances above five in the entire viable parameter space of the fermiophobic type-I with a high cutoff scale.

The objective of the present work was to determine effects of reducing dietary crude protein (CP) concentrations with indispensable amino acid (AA) supplementation on nitrogen balance and urinary pH in growing pigs. Three experiments were conducted using 12 barrows with an initial body weight of 29.9, 50.2, and 78.2 kg (standard deviation = 1.8, 2.2, and 3.7, respectively) individually housed in metabolism crates. In each experiment, a quadruplicated 3 × 2 incomplete Latin square design with 3 diets varying CP concentrations in each experiment and 2 periods per square was employed. In experiments 1 and 2, experimental diets based on corn, soybean meal, corn distillers dried grain with solubles, and rapeseed meal were formulated to contain 16.8, 15.0, and 13.2% CP as-fed basis and 16.8, 14.9, and 13.1% CP as-fed basis, respectively. In experiment 3, experimental diets based on corn and soybean meal were formulated to contain 15.1, 13.2, and 11.4% CP as-fed basis. All diets were supplemented with indispensable AA to meet all indispensable AA requirements. Each period consisted of a 5-day adaptation period followed by a 4-day collection period. On days 6 and 10, chromic oxide was added at 0.5% in morning meals as a marker and the marker-to-marker procedure was used for the quantitative collection of feces. Urine collection was initiated at 10:00 on day 6 and terminated at 10:00 on day 10. Polynomial contrasts were performed to test linear and quadratic effects of dietary CP concentrations on the response variables in each experiment. In all experiments, daily N intake was linearly decreased (P < 0.05) with decreasing dietary CP concentrations. Decreasing dietary CP concentrations resulted in linear reduction in daily fecal N excretion (P < 0.05) in experiment 2 and linear reductions in daily urinary N excretion (P < 0.05) in all experiments. Total N excretion linearly decreased (P < 0.05) with decreasing dietary CP concentration in all experiments. The urinary pH obtained from 30- and 50-kg pigs was linearly decreased (P < 0.05) with decreasing dietary CP concentrations. In conclusion, lowering dietary CP concentrations decreased N excretion and urinary pH in 30-, 50-, and 78-kg pigs. [ABSTRACT FROM AUTHOR]

The objective of the present study was to develop prediction equations for daily phosphorus excretion based on body weight (BW) and dietary phosphorus concentration of pigs. Four experiments were conducted using pigs with an initial body weight of 15 kg, 30 kg, 50 kg, and 78 kg. In the experiment 1, the experimental diets were mainly based on corn, soybean meal, whey powder, fish meal, and blood plasma. In the experiments 2, 3, and 4, the diets based on corn, soybean meal, and fibrous ingredients were formulated. All experimental diets were supplemented with commercial phytase at 500 FTU/kg. In all experiments, a total collection method and the marker-to-marker procedure were used for fecal and urinary collection. Fecal and urinary phosphorus excretions were determined. Correlation coefficients among BW, daily phosphorus intake, and daily phosphorus excretion of pigs were determined. Prediction equations for phosphorus excretion were developed using BW and dietary phosphorus concentration as independent variables. The BW had positive correlations with fecal and total phosphorus excretion (r = 0.78 and P < 0.001 for fecal phosphorus excretion and r = 0.78 and P < 0.001 for total phosphorus excretion). The prediction equations for predicting fecal phosphorus excretion and total phosphorus excretion were: fecal phosphorus excretion (g·pig-1·d-1) = -0.647 - 0.00065 × BW² + 0.270 × BW × dietary phosphorus concentration (R² = 0.81; P < 0.001); total phosphorus excretion (g·pig-1·d-1) = -0.619 - 0.00064 × BW² + 0.277 × BW × dietary phosphorus concentration (R² = 0.85; P < 0.001) where BW in kg and phosphorus concentration in %. The BW of pigs corresponding to the age was predicted using the NRC model. The mean phosphorus excretion of pigs weighing from 7 kg to 120 kg at day 22 to 180 was calculated using a developed estimation equation, with BW and total phosphorus requirement used as independent variables. Daily fecal and total phosphorus excretions were 3.77 g·pig-1·d-1 and 4.01 g·pig-1·d-1, respectively. [ABSTRACT FROM AUTHOR]

Prediction models for estimating feed intake (FI) or metabolizable energy intake (MEI) of pigs are available in the literature. During the recent two decades, several reports have addressed the influence of heat stress on FI. The objectives of the present work were to validate the accuracy of prediction equations for estimating FI or MEI of pigs in the literature using data from heat stress experiments and to develop novel equations for estimating FI and MEI of pigs under thermoneutral or heat stress environment. A total of 123 data from 25 research papers measuring the effects of heat stress on FI of pigs published between 2001 and 2021 were used for the validation of previous equations and the development of novel equations. In the 25 papers, the thermoneutral temperature (T) ranged from 17 to 24℃ and the heat stress T ranged from 21 to 35℃. The body weight (BW) of pigs ranged from 19 to 119 kg. In the first validation study, the equation for estimating FI was evaluated: FI, g/day = -1,264 + 73.6×BW - 0.26×BW² + 117×T - 2.40×T² - 0.95×T×BW. The slope representing a linear bias did not differ from 0 but the intercept representing a mean bias was greater than 0 (109 ± 36; P < 0.01), meaning that the predicted mean underestimated the FI. In the second validation study, the equation for estimating MEI using equations for lower critical temperature (LCT) and fraction of MEI: LCT, ℃ = 17.9 - 0.0375×BW and fraction of MEI = 1 - 0.012914 × [T - (LCT + 3)] - 0.001179 × [T - (LCT + 3)]2. The slope representing a linear bias did not differ from 0 but the intercept representing a mean bias was greater than 0 (731 ± 68; P < 0.001), meaning that the predicted mean underestimated the MEI. A novel equation for estimating MEI under thermoneutral or heat stress environment was developed: MEI, kcal/day = 2,603 + 137×BW - 0.189×BW² - 38.4×T - 0.556×T² - 1.165×T×BW (P < 0.001; R² = 0.83). An equation for estimating fraction of MEI under thermoneutral or heat stress environment was also developed: fraction of MEI = 1 - 0.00677 × [T - (LCT + 3)] - 0.000668 × [T - (LCT + 3)]² (P < 0.001; R² = 0.98). In conclusion, previously published equations underestimate FI and MEI and novel equations for estimating MEI under thermoneutral or heat stress environment have been developed in the present work. However, the novel equations have not been validated under cold stress. [ABSTRACT FROM AUTHOR]

The objective of the present work was to determine digestible energy (DE) and metabolizable energy (ME) concentrations of corn, oilseed meals, and fibrous ingredients fed to growing pig. Twelve barrows with an initial body weight of 34.3 kg (SD = 2.9) were individually housed in metabolism crates. A 12 × 8 incomplete Latin square design with 12 animals, 12 experimental diets, and 8 periods was employed. A basal diet contained 76.7% corn, 19.0% soybean meal (SBM), and 2% soybean oil as the sole source of energy. Ten experimental diets were prepared by replacing 30% of the basal diet with SBM, rapeseed meal, rice bran, corn gluten feed, corn distillers dried grain with solubles (DDGS), wheat bran, sugar beet pulp, copra meal, soybean hulls, or palm kernel expellers. Additionally, a corn diet contained 97.7% of corn as a sole energy source. Each period consisted of a 5-day adaptation period and a 5-day collection period, and the marker-to-marker procedure was used for the quantitative collection of feces and urine. The gross energy concentrations in the experimental diets were close to the calculated values based on the ingredient gross energy values. The DE and ME concentrations in corn (3,911 and 3,866 kcal/kg DM) and SBM (4,004 and 3,780 kcal/kg DM) were greatest (P < 0.05) among the 11 test ingredients followed by DDGS (3,531 and 3,336 kcal/kg DM), rice bran (3,242 and 3,172 kcal/kg DM), soybean hulls (3,081 and 3,103 kcal/kg DM), palm kernel expellers (3,112 and 3,058 kcal/kg DM). The DE and ME concentrations in corn gluten feed (2,624 and 2,460 kcal/kg DM) were less (P < 0.05) than those in all other test ingredients. In conclusion, corn and SBM had the greatest energy values among the corn, oilseed meals, and fibrous ingredients, whereas corn gluten feed had the lowest energy values. [ABSTRACT FROM AUTHOR]

In vitro procedures using flasks have been used for simulating nutrient utilization by pigs. However, these procedures are time-consuming and laborious and require a number of flasks and filter crucibles. The objective of this study was to develop an in vitro procedure using DaisyII incubator for simultaneous analysis of multiple samples. In a conventional in vitro procedure, 10 mg of pepsin in step 1 and 50 mg of pancreatin in step 2 are used for each flask containing 1 g of feed sample. In a preliminary experiment, 24 samples each in R55 bags were digested in a jar of DaisyII incubator with 24 times the quantity of buffer solution and enzymes of the conventional flask procedure. In the preliminary experiment, greater crude protein (CP) digestibility values were observed in the DaisyII incubator procedure compared with the conventional flask procedure. To determine optimum enzyme doses in the in vitro ileal disappearance (IVIDDaisy) procedure using the DaisyII incubator, 3 doses of pepsin (10, 7.5, and 5 mg/sample in step 1) and 3 doses of pancreatin (50, 37.5, and 25 mg/sample in step 2) were tested in a 3 × 3 factorial arrangement for 11 test ingredients. The quantity of buffer solution and enzymes in a jar was increased proportionally with the number of samples. The 11 test ingredients were barley, copra meal, corn, corn distillers dried grains with solubles, corn gluten feed, corn gluten meal, palm kernel meal, rice bran, soybean hulls, soybean meal, and wheat bran. The in vitro ileal disappearance (IVIDflask) of CP in the 11 ingredients was determined using the conventional flask procedure. The sum of square of deviation between IVIDflask of CP and IVIDDaisy of CP was the least when 5 mg pepsin/sample in step 1 and 37.5 mg/sample in step 2 were used (IVIDflask of CP, % = 14.4 + 0.81 × IVIDDaisy of CP, %; r2 = 0.748). On the other hand, the determination coefficient was the greatest when 10 mg pepsin/sample in step 1 and 50 mg/sample in step 2 were used (IVIDflask of CP, % = 2.5 + 0.93 × IVIDDaisy of CP, %; r2 = 0.878). In conclusion, the in vitro procedure using a DaisyII incubator can be used for estimating ileal digestibility of protein in multiple samples simultaneously for pigs. [ABSTRACT FROM AUTHOR]

The objective of the present work was to determine the effects of reucing dietary crude protein (CP) concentrations with essential amino acid (EAA) supplementation on nitrogen balance, urinary pH, and slurry pH in nursery pigs. Twelve barrows with an initial body weight of 15.2 kg (standard deviation = 0.7) were individually housed in metabolism crates. A quadruplicated 3 × 2 incomplete Latin square design with 3 experimental diets and 2 periods per square was employed. Experimental diets based on corn, soybean meal, whey powder, fish meal, and blood plasma were formulated to contain 19.4% CP, 17.5% CP, and 15.7% CP by reducing inclusion rates of soybean meal. All experimental diets were supplemented with EAA to meet all EAA requirements. Each period consisted of a 4-day adaptation period and a 24-hour collection period followed by a 4-day collection period. On day 5, feces and urine were collected for 24 h and the feces and urine were mixed in a ratio of fecal weight and urine weight at the end of collection to obtain slurry samples. Then, pH of urine and slurry samples was measured immediately. On days 6 and 10, chromic oxide was added at 0.5% in morning meals as a marker and the marker-to-marker procedure was used for the quantitative collection of feces. Urine collection was initiated at 1000 h on day 6 and terminated at 1000 h on day 10. Orthogonal polynomial contrasts were performed to test linear and quadratic effects of dietary CP concentrations on the response variables. Daily N intake was linearly decreased with decreasing dietary CP concentrations (P < 0.05). Daily fecal and urinary N excretions linearly decreased with decreasing dietary CP concentrations (P < 0.05), whereas N retention rate as % of intake was linearly increased with decreasing dietary CP concentrations (P < 0.05). The urine pH and slurry pH were linearly decreased with decreasing dietary CP concentrations (P < 0.05). In conclusion, lowering dietary CP concentrations decreased N excretion and pH of urine and slurry. [ABSTRACT FROM AUTHOR]

The null results in the new physics searches at the LHC do not exclude a light new particle if the particle is fermiophobic. A good example is the fermiophobic Higgs boson hf in the type-I two-Higgs-doublet model, which occurs if we adopt α=π/2 and the inverted scenario where the heavier CP-even Higgs boson is the observed one at a mass of 125 GeV. We first obtain the still-valid parameter space satisfying the theoretical requirements, flavor-changing neutral currents in B physics, the cutoff scale above 1 TeV, Higgs precision data, and the direct search bounds at high energy colliders. We also study the high energy scale behavior of the allowed parameter points via the renormalization group equation analysis. An important result is that the fermiophobic type-I can maintain the stability of the scalar potential all the way up to the Planck scale if mhf is larger than half the observed Higgs boson mass. Since the decay modes of hf→γγ, H±→hfW±, and A→hfZ are dominant, the productions of pp→Ahf/H±hf/H±A/H+H− yield the four-photon final states at the LHC. We suggest the processes of 4γ+VV′ (V(′)=Z,W±) as the discovery channels that supplement 4γ+V, since they have compatible cross sections and enjoy the background-free environment.

The measurement of the Higgs quartic coupling modifier between a Higgs boson pair and a vector boson pair, κ2V, is expected to be achieved from vector-boson fusion (VBF) production of a Higgs boson pair. However, this process involves another unmeasured parameter, the trilinear Higgs self-coupling modifier κλ. A sensitivity analysis should target both parameters. Since the LHC cannot avoid the gluon fusion pollution, which becomes severe for non-SM κλ, an electron-proton collider is more appropriate for the comprehensive measurement. In this regard, we study the VBF production of a Higgs boson pair in the bb¯bb¯ final state at the LHeC and FCC-he. Performing detailed analysis using simulated dataset, we devise the search strategy specialized at the LHeC and FCC-he and give a prediction for the sensitivity to both κ2V and κλ. We find that the two electron-proton colliders have high potential: the LHeC has similar exclusion prospects as the HL-LHC; the FCC-he is extremely efficient, excluding the parameter space outside κ2V∈[0.8,1.2] and κλ∈[1,2.5] at 95% C.L. for the total luminosity of 10 ab−1 and 10% uncertainty on the background yields.

The objective was to determine the effects of different drying methods on nutrient utilization of black soldier fly (BSF; Hermetia illucens) larva meals using in vitro assays. Two-step and 3-step in vitro assays were employed to simulate the gastrointestinal tract of pigs. Four methods were used to obtain BSF larva meal sources: 1) microwave-drying for 32 min, 2) hot-air drying at 60°C for 17 h, 3) water blanching for 5 min and hot-air drying for 17 h, and 4) 2% citric acid solution blanching for 5 min and hot-air drying for 17 h. After the drying process, each BSF larva was defatted and ground to obtain BSF larva meals. The crude protein (CP) concentration in the test ingredients ranged from 54.7 to 60.4% on dry matter (DM) basis and ether extract ranged from 7.1 to 11.8% DM. Hot-air-dried BSF larva meal had greater in vitro ileal disappearance (IVID) of CP compared with microwave-dried BSF larva meal (86.7% vs. 84.4%; P < 0.05). However, blanching BSF larva in water or 2% citric acid solution before hot-air drying resulted in less IVID of CP (81.3 or 82.5%; P < 0.05) compared with microwave-dried or hot-air-dried BSF larva meal. Blanching BSF larva in water or 2% citric acid solution before hot-air drying resulted in less in vitro total tract disappearance of DM (85.0% or 84.5% vs. 90.4% or 89.6%; SEM = 0.3, P < 0.05) and OM (80.6% or 81.5% vs. 85.7% or 86.6%; SEM = 0.1, P < 0.05) compared with microwave-dried or hot-air-dried BSF larva meal. In conclusion, hot-air-dried BSF larva meal had greater nutrient utilization compared with microwavedried BSF larva meal. However, blanching BSF larva in water or citric acid solution negatively affected nutrient digestibility based on in vitro assays. [ABSTRACT FROM AUTHOR]

The objective of the present study was to develop prediction equations for digestible energy (DE) and metabolizable energy (ME) in swine diets based on chemical compositions of feces with no dietary information. A total of 262 fecal samples obtained from growing pigs fed 27 diets from 4 experiments were used. The diets were based mainly on corn, soybean meal, and other plant-originated feed ingredients. In the digestibility experiments, feces and urine were quantitatively collected using the marker-to-marker procedure. The diet and fecal samples were analyzed for dry matter (DM), crude protein, ash, and neutral detergent fiber (NDF). Digestible energy in the 27 diets ranged from 2,907 to 4,374 kcal/kg DM and ME ranged from 2,774 to 3,983 kcal/kg DM. Fecal ash was positively correlated with DE (r = 0.81, P < 0.001) and ME (r = 0.66, P < 0.001) whereas fecal NDF was negatively correlated with DE (r = -0.66, P < 0.001) and ME (r = -0.74, P < 0.001). The energy prediction equations developed using fecal chemical components were: energy digestibility = 88.1 + 0.37 × ash - 0.28 × NDF (R2 = 0.57, P < 0.001); DE (kcal/kg DM) = 3,604 + 32.8 × ash - 11.1 × NDF (R2 = 0.71, P < 0.001); and ME (kcal/kg DM) = 4,077 + 15.7 × ash - 18.1 × NDF (R2 = 0.63, P < 0.001) where chemical components are expressed as % DM. In conclusion, energy digestibility, DE values, and ME values in swine diets are correlated with fecal ash and NDF concentrations and the energy values can be predicted using fecal ash and NDF concentrations without dietary information. [ABSTRACT FROM AUTHOR]