RESUMEN
Public discourse around "greenhouse gases" (GHG) has led to the application of life-cycle assessments to ascertain the "global warming potential" of human activities. Life-cycle assessments applied to agricultural systems typically do not consider positive contributions (i.e., fixation of atmospheric carbon dioxide [CO2]) or consider complex interrelationships among commodities within the larger agricultural sector. The purpose of this article is to present an argument for a paradigm shift and that poultry production should be considered as a value-adding activity within modern crop production systems for GHG foot-printing purposes. To this end, a case study based on 2018 production data is presented where poultry production (chicken and eggs) was contextualized as a sub-component of wheat and corn production in the Canadian provinces of Alberta and Ontario, respectively. Total GHG footprint was calculated to be 3.05 and 3.29 million tonnes (MT) of CO2 equivalent (eq) for Alberta wheat and Ontario corn production, respectively. The GHG footprint of chicken production was calculated to be 0.39 and 1.38 MT CO2 eq in Alberta and Ontario, respectively. The GHG footprint of egg production calculated to be 0.12 and 0.47 MT of CO2 eq in Alberta and Ontario, respectively. When carbon (C) fixation as crop biomass is included in the scenario, the combined crop-poultry system C balance in 2018 favored net fixation of 40.70 and 35.15 MT of CO2 eq in Alberta and Ontario, respectively. The calculated total GHG footprint of poultry production in Alberta and Ontario corresponded to only 1.2 and 5.5% of the calculated total net CO2 fixation of their respective cropping systems. This case study demonstrates that by failing to acknowledge real world estimates of C fixation by crop biomass, GHG foot-printing exercises largely misrepresent reality and can thus perpetuate faulty assumptions about the environmental footprint of animal agriculture. The authors propose that the calculations presented herein provide grounds to postulate the hypothesis that modern, integrated crop-livestock agricultural systems in Canada (and elsewhere) act as net sinks for atmospheric CO2.
Asunto(s)
Agricultura , Producción de Cultivos , Gases de Efecto Invernadero , Aves de Corral , Agricultura/estadística & datos numéricos , Alberta , Animales , Producción de Cultivos/estadística & datos numéricos , Huevos , Ontario , Aves de Corral/fisiologíaRESUMEN
Two experiments evaluated feeding Brassica (B.) napus (canola) or B. juncea co-products to brown-shelled egg laying hens. In Exp. 1, diets including 20% B. napus or B. juncea extruded-expelled cakes (NC, JC) or solvent-extracted meals (NM, JM) compared to a control diet with no Brassica co-products, were fed to 120 hens (4 hens/cage, n = 6) for 36 wk. In Exp. 2, DM, gross energy, CP and amino acid (AA) retention/digestibility was determined by feeding diets containing 30% B. napus or B. juncea cakes or meals and basal diet to 240 hens (8 hens/pair of cages, n = 6) for 7 d. Cakes averaged 40 g/kg lower moisture, 28 g/kg lower CP, and 84 g/kg greater fat content compared with meals. In Exp. 1, there was no effect of diet on lay percentage or BW throughout the experiment. Feed consumption was 3.5 g/d lower in layers fed JM compared with controls and egg: feed was reduced by 14 mg egg/g feed in layers fed JC (P < 0.01). Although eggs from layers fed NM were 0.7 g heavier than controls, eggs from layers fed NC, JM or JC were 1.4 g lighter than controls (P < 0.01). Eggs from layers fed Brassica diets contained a greater proportion (1.6%-points) of monounsaturated fatty acids compared with controls (P < 0.01). Eggs from layers fed B. juncea had a relatively greater proportion (0.2%-points) of C18:3 (n3) compared with those of layers fed B. napus diets (P < 0.01). Feeding Brassica diets reduced digestibility of DM (5%-points), gross energy (7%-points) and CP (4%-points) vs. basal (P < 0.01). The digestibility of indispensable AA except tryptophan, was reduced feeding Brassica diets vs. basal (P < 0.01). We concluded that feeding B. napus and B. juncea extruded-expelled cakes and solvent-extracted meal at 20% of diets to hens supported acceptable lay performance and egg quality over a 36 wk production cycle. Digestibility data indicated that indispensable AA in Brassica co-products had moderately high (75 to 85%) apparent ileal digestibility.
Asunto(s)
Alimentación Animal/análisis , Brassica napus , Pollos/fisiología , Planta de la Mostaza , Aminoácidos , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/veterinaria , Digestión , Huevos/análisis , Ácidos Grasos Monoinsaturados/análisis , Femenino , Oviposición/fisiología , SemillasRESUMEN
Digestibility of remaining oil in canola press-cake (CPC) may be lower than that of extracted, liquid canola oil (CO) because oil may be partly entrapped in the CPC matrix. To determine true digestibility of fat in ingredients, endogenous fat losses should be estimated. Dietary fat may interact with digestion of other dietary components. To test these hypotheses, 10 ileal-cannulated pigs (initial BW, 25.4 kg) were fed 10 diets for 8 periods in a 10 × 8 Youden square. A basal diet was formulated based on wheat, barley, and canola meal. The 4 CPC and 4 CO test diets were prepared by replacing identical portion of basal diet with 10%, 20%, 30%, or 40% CPC, or 1.5%, 3.0%, 4.5%, or 6.0% CO, respectively, to match the fat content of CPC diet with CO diet at each fat level. An N-free diet based on corn starch was prepared to measure basal endogenous losses of AA. Apparent total tract digestibility (ATTD) and apparent ileal digestibility (AID) of acid-hydrolyzed ether extract (AEE) were calculated for each diet. True ileal digestibility (TID) and true total tract (TTTD) digestibility of AEE in CPC and CO, and total endogenous losses of AEE were estimated by regressing apparent digestible AEE (g/kg of DMI) against dietary AEE intake (g/kg of DM) at the total tract and distal ileum, respectively. The mean AID and ATTD of AEE in CPC diets were 78.9% and 61.5%, which were lower ( < 0.01) than 81.9% and 63.4% in CO diets. Apparent ileal and total tract digestible AEE content in CPC and CO diets increased linearly ( < 0.01) with increasing AEE intake. Endogenous losses of AEE were greater ( < 0.05) for the total tract than for the ileum (23.4 vs. 9.4 g/kg of DMI). Dietary fat source did not affect ( > 0.05) total tract or ileal endogenous losses of AEE. The TID and TTTD of AEE in CPC were 92.3% and 94.5%, respectively, lower ( < 0.01) than 96.5% and 100% in CO. Increasing dietary inclusion of CO linearly increased ( < 0.001) standardized ileal digestibility (SID) of CP, Lys, Met, Thr, and Trp, and quadratically increased ( < 0.001) the AID and ATTD of energy in the basal part of the test diets. In conclusion, CPC had lower TID and TTTD of AEE than CO. Dietary fat source did not affect endogenous losses of AEE. The lower digestibility of AEE in CPC than in CO indicates that fat digestibility of CPC should be considered to predict its nutritional value accurately. Dietary inclusion of CO may increase digestibility of CP and energy originating from the balance of the diet.
Asunto(s)
Alimentación Animal/análisis , Brassica napus , Dieta/veterinaria , Grasas de la Dieta/administración & dosificación , Digestión/efectos de los fármacos , Aceite de Brassica napus , Aminoácidos/metabolismo , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Brassica napus/metabolismo , Grasas de la Dieta/farmacología , Íleon/metabolismo , Masculino , Valor Nutritivo , PorcinosRESUMEN
Feeding cake with remaining oil contributes dietary energy (fat) in addition to protein (AA) and may provide an opportunity to enrich the n-3 fatty acid content of pork. Information regarding safety, growth performance, and efficacy of feeding camelina cake to pigs is limited. We therefore evaluated the effects of camelina cake inclusion in pig nursery diets. In total, 192 pigs (9.4 kg BW) were randomly allocated by sex to 48 pens, 2 heavy and 2 light pigs per pen. Pigs were fed 1 of 4 wheat-based diets including camelina cake (0%, 6%, 12%, or 18%; variety Celine) replacing soybean meal for 4 wk. Individual pigs, pen feed added, and orts were weighed weekly. Feces were collected on d 26 and 27. A blood sample was taken on d 29 from 24 pigs with the lowest BW/pen, which were then euthanized and necropsied. Gross pathological examination was conducted, and organ weights were measured. Samples of liver, back fat, belly fat, and jowl fat were collected for fatty acid analysis. Increasing dietary camelina cake inclusion linearly decreased ( 0.001) apparent total tract digestibility (ATTD) of DM, OM, GE and ash but did not affect ATTD of CP and P. For the entire trial (d 0 to 28), increasing camelina cake inclusion by 6% linearly decreased ( 0.001) ADFI by 74 g/d, ADG by 51 g/d, and BW by 0.8 kg but did not affect feed efficiency (G:F). Increasing camelina cake inclusion linearly increased ( 0.001) liver weight relative to BW, linearly decreased ( 0.050) kidney weight, but did not affect spleen, heart, and thyroid weights. Increasing camelina cake inclusion did not result in serological (large-animal standard panel, T3, and T4) or gross clinical (morphology) findings that might suggest toxicity. In liver, back fat, belly fat, and jowl fat, increasing dietary camelina cake inclusion linearly increased ( 0.050) total n-3 fatty acids and shorter-chain n-3 and n-6 fatty acids but did not increase docosahexaenoic acid (n-3) or arachidonic acid (n-6). In conclusion, feeding camelina cake to weaned pigs at up to 18% did not elicit clinical signs of toxicity and increased n-3 fatty acids in carcass fat depots. The decrease in ADFI as camelina cake inclusion increased resulted in pigs fed 18% weighing 5 kg less than controls at the end of the nursery period.
Asunto(s)
Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Ácidos Grasos/análisis , Carne Roja/análisis , Porcinos/fisiología , Animales , Composición Corporal , Brassica , Dieta/veterinaria , Grasas de la Dieta/análisis , Grasas de la Dieta/metabolismo , Ácidos Grasos/metabolismo , Ácidos Grasos Omega-3/análisis , Ácidos Grasos Omega-3/metabolismo , Ácidos Grasos Omega-6/análisis , Ácidos Grasos Omega-6/metabolismo , Femenino , Masculino , Distribución Aleatoria , Glycine max , Porcinos/crecimiento & desarrollo , Triticum , DesteteRESUMEN
Feeding cake with remaining oil content not only provides additional dietary energy but may also enrich pork with -3 fatty acids. Limited information is available on feeding camelina cake to pigs relating to feeding safety (toxicity), growth performance, and efficacy of -3 enrichment of pork. Therefore, we evaluated the effects of feeding increasing camelina cake (12.2% crude fat) inclusions in diets for nursery and grower-finisher pigs. In total, 128 pigs (9.2 kg BW) were randomly allocated by sex to 32 nursery pens for 4 wk and were then moved and combined into 16 mixed-sex grower-finisher pens. Pigs were fed 1 of 4 wheat/barley-based diets including camelina variety 'Celine' cake (0%, 6%, 12%, or 18% in the nursery phase and 0%, 5%, 10%, or 15% in the grower-finisher phase) replacing soybean meal over 5 feeding phases (d 0 to 7, d 7 to 28, d 28 to 56, d 56 to 84, and d 84 to slaughter). Individual pigs and pen feed added were weighed. On d 106, a blood sample was collected from the pig with the lowest BW per pen, which was then euthanized. A pathologist conducted a gross clinical examination, and organs were weighed. Liver, back fat, and belly and jowl fat were sampled for fatty acid analysis. Pigs were slaughtered at approximately 125 kg BW. Increasing dietary camelina cake inclusion linearly decreased ( < 0.010) ADFI, ADG, BW, and G:F over the 105-d trial. Increasing dietary camelina cake inclusion linearly increased days to slaughter ( < 0.001) and carcass lean yield ( < 0.010) and linearly decreased farm ship weight ( < 0.010), carcass weight ( < 0.001), dressing percentage ( < 0.050), and back fat thickness ( < 0.010) but did not affect loin depth and index. Increasing camelina cake inclusion linearly increased liver and pancreas weight ( < 0.050) relative to BW but did not affect heart, thyroid, or kidney weights. Increasing camelina cake inclusion did not result in gross clinical or serological findings that would indicate toxicity. Increasing dietary camelina cake inclusion linearly increased ( < 0.050) -3 fatty acids, including docosahexaenoic acid, in back fat and belly and jowl fat. In conclusion, feeding camelina cake to pigs at up to 18% in the nursery phase and 15% in the grower, developer, and finisher phases did not result in clinical signs of toxicity and enriched carcass fat depots with -3 fatty acids. The observed decrease in ADFI and, consequently, ADG as camelina cake inclusion increased resulted in pigs fed 15% reaching slaughter weight 27 d later than controls.
Asunto(s)
Brassicaceae , Grasas de la Dieta/metabolismo , Carne Roja/análisis , Porcinos/fisiología , Alimentación Animal/análisis , Animales , Composición Corporal/efectos de los fármacos , Dieta/veterinaria , Ácidos Grasos/análisis , Masculino , Carne/análisis , Glycine max , Porcinos/crecimiento & desarrollo , Triticum , DesteteRESUMEN
Feeding fermented feed to weaned pigs may improve nutrient digestibility and gut health and thereby reduce diarrhea incidence. Effects of feeding wheat grain fermented for 24 h with were evaluated with 36 weaned pigs (7.3 kg BW). Fermented wheat grain contained (DM basis) 14.2% CP, 0.45% chemically available Lys, and 7.8% NDF, whereas unfermented wheat grain contained 16.4% CP, 0.45% chemically available Lys, and 9.9% NDF. Pigs were fed 6 mash wheat-based diets balanced for water content during 2 phases: Phase 1 diets for 1 wk (d 0-7) with 20% unfermented or fermented wheat and, subsequently, Phase 2 diets for 2 wk (d 8-21) with 50% unfermented or fermented wheat. The 6 diets were unfermented wheat (CTRL), unfermented and chemically acidified wheat (ACD), fermented wheat with TMW1.656 and 10% sucrose, fermented wheat with TMW1.656 and 5% glucose + 5% fructose, fermented wheat with LTH5794 and 10% sucrose, and fermented wheat with LTH5794 and 5% glucose + 5% fructose. Diets were formulated to provide 2.5 and 2.4 Mcal NE/kg and 5.3 and 5.0 g standardized ileal digestible Lys/Mcal NE for Phase 1 and 2 diets, respectively. Feeding fermented wheat reduced ( < 0.05) apparent total tract digestibility (ATTD) of diet DM (84.7 vs. 85.4%), GE (84.4 vs. 85.3%), and CP (81.8 vs. 83.6%) for d 15 through 21 compared with the CTRL and ACD diets. Weaned pigs fed fermented wheat diets had lower ( < 0.05) ADFI than pigs fed the CTRL and ACD diets for d 0 through 7. The ADFI, ADG, and G:F did not differ between pigs fed fermented and unfermented diets. Concentrations of acetic, propionic, and branched-chain fatty acids and total VFA in feces increased ( < 0.05) for pigs fed fermented wheat diets containing exopolysaccharides (EPS). However, VFA did not differ in ileal digesta. Villus height in the duodenum and jejunum increased in pigs fed fermented wheat without EPS ( < 0.05) compared with pigs fed fermented wheat with EPS. However, pigs fed the CTRL and ACD diets had longer ( < 0.05) villi and deeper crypts in the ileum than pigs fed fermented wheat. The ratio of villus height to crypt depth did not differ in the 3 segments of small intestine of weaned pigs. In conclusion, feeding fermented wheat grain diets to weaned pigs did not affect gut morphology, intestinal fermentation, growth performance, and ATTD of nutrients; however, EPS stimulated hindgut fermentation and may promote health benefits.
Asunto(s)
Alimentación Animal/análisis , Dieta/veterinaria , Tracto Gastrointestinal/anatomía & histología , Limosilactobacillus reuteri/fisiología , Porcinos/fisiología , Triticum/química , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Reactores Biológicos , Digestión/efectos de los fármacos , Heces/química , Fermentación , Tracto Gastrointestinal/efectos de los fármacos , Probióticos , Porcinos/crecimiento & desarrolloRESUMEN
The objectives were to determine the standardized ileal digestibility (SID) of amino acids (AA) and AMEn value of cold-pressed camelina cake (CPCC) and the effect of adding multi-enzyme to a corn-CPCC diet for broilers. The 600 male broiler chicks were divided into 40 groups and fed 5 diets in a completely randomized design (8 groups per diet) from d 15 to d 21 of age. A corn basal diet and the basal diet with 30% of it replaced by CPCC were used in a 2 × 2 factorial arrangement with or without multi-enzyme (2,800 U of cellulase, 1,800 U of pectinase, 400 U of mannanase, 50 U of galactanase, 1,000 U of xylanase, 600 U of glucanase, 2,500 U of amylase, and 200 U of protease/kilogram of diet; Superzyme OM, 1 g/kg). The fifth diet was N-free. The corn basal diet was fed to determine nutrient digestibility and retention for CPCC by substitution. The N-free diet was fed to estimate basal endogenous AA losses for determining SID of AA. Diets contained TiO2 as indigestible marker. On a DM basis, CPCC contained 39.8% CP, 38.3% neutral detergent fiber, 12.7% ether extract, 1.89% Lys, 0.70% Met, 1.56% Thr, and 0.45% Trp. The SID of Lys, Met, Thr, and Trp for CPCC were 76.5, 85.5, 72.8, and 84.1%, respectively. The AMEn value for CPCC was 1,671 kcal/kg of DM. Multi-enzyme supplementation increased (P < 0.05) the SID of Met and Thr and the AMEn value of the corn-CPCC-based diet by 1.4, 1.3, and 3.0%, respectively. The multi-enzyme increased (P = 0.026) the AMEn value of CPCC from 1,671 to 1,941 kcal/kg of DM. In conclusion, the CPCC evaluated in the present study can be included in poultry diets as a source of energy and AA. Multi-enzyme supplementation increased the AMEn value of CPCC for broilers.
Asunto(s)
Brassicaceae/química , Pollos/fisiología , Metabolismo Energético , Valor Nutritivo , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/veterinaria , Suplementos Dietéticos/análisis , Digestión/efectos de los fármacos , Íleon/fisiología , Masculino , Distribución AleatoriaRESUMEN
Canola co-products are sources of amino acid and energy in pig feeds, but their fermentation characteristics in the pig intestine are unknown. Thus, we determined the in vitro fermentation characteristics of the canola co-products Brassica juncea solvent-extracted canola meal (JSECM), Brassica napus solvent-extracted canola meal (NSECM), B. napus expeller-pressed canola meal (NEPCM) and B. napus cold-pressed canola cake (NCPCC) in comparison with soybean meal (SBM). Samples were hydrolysed in two steps using pepsin and pancreatin. Subsequently, residues were incubated in a buffer solution with fresh pig faeces as inocula for 72 h to measure gas production. Concentration of volatile fatty acids (VFA) per gram of dry matter (DM) of feedstuff was measured in fermented solutions. Apparent ileal digestibility (AID) and apparent hindgut fermentation (AHF) of gross energy (GE) for feedstuffs were obtained from pigs fed the same feedstuffs. On DM basis, SBM, JSECM, NSECM, NEPCM and NCPCC contained 15, 19, 22, 117 and 231 g/kg ether extract; and 85, 223, 306, 208 and 176 g/kg NDF, respectively. In vitro digestibility of DM (IVDDM) of SBM (82.3%) was greater (P<0.05) than that of JSECM (68.5%), NSECM (63.4%), NEPCM (67.5%) or NCPCC (69.8%). The JSECM had greater (P<0.05) IVDDM than NSECM. The IVDDM for NSECM was lower (P<0.05) than that for NEPCM, which was lower (P<0.05) than that for NCPCC. Similarly, AID of GE was greatest for SBM followed by NCPCC, JSECM, NEPCM and then NSECM. Total VFA production for SBM (0.73 mmol/g) was lower (P<0.05) than that of JSECM (1.38 mmol/g) or NSECM (1.05 mmol/g), but not different from that of NEPCM (0.80 mmol/g) and NCPCC (0.62 mmol/g). Total VFA production of JSECM was greater (P<0.05) than that of NSECM. Total VFA production of NSECM was greater (P<0.05) than that of NEPCM or NCPCC, which differed (P<0.05). The ranking of feedstuffs for total VFA production was similar to AHF of GE. In conclusion, in vitro fermentation characteristics of canola co-products and SBM simulated their fermentation in the small and large intestine of pigs, respectively. The 30% greater VFA production for JSECM than NSECM due to lower lignified fibre of JSECM indicates that fermentation characteristics differ between canola species. The NSECM had the highest fermentability followed by NEPCM and then NCPCC, indicating that fat in canola co-products can limit their fermentability in the hindgut.
Asunto(s)
Brassica napus/metabolismo , Digestión , Fermentación , Mucosa Intestinal/metabolismo , Porcinos/metabolismo , Animales , Brassica napus/química , Dieta/veterinaria , Fibras de la Dieta/metabolismo , Ácidos Grasos Volátiles/metabolismo , Heces/química , Hidrólisis , Íleon/metabolismo , Técnicas In Vitro , Glycine max/química , Glycine max/metabolismoRESUMEN
The benefits to human from the consumption of omega-3 polyunsaturated fatty acids (N-3 PUFAS) have been recognized. Camelina sativa is an oilseed crop grown for biofuel production. Feeding its cake with 10 to 20% remaining oil (28 to 30% α-linolenic acid [ALA]) has the potential to enrich poultry products with n-3 PUFA. An experiment was conducted to assess lipid deposition in brain, liver, breast, and thigh tissue by increasing inclusions of camelina cake (CC) fed to broiler chickens. Male chicks (744, Ross 308) housed in 24 cages were fed 0, 8, 16, or 24% CC for 42 d, 6 replicates per CC level. At the end of the starter (14 d), grower (28 d), and finisher (42 d) phase, brain, liver, breast, and thigh samples were collected from 3 birds/cage and diets were analyzed for fatty acid content. Feeding increasing CC inclusions from 0 to 8, 16, and 24% increased dietary ALA (5.3, 11.1, 15.2, 17.8, respectively) as a proportion of the total fatty acid content. All diets provided a similar level of long-chain n-3 PUFA (about 0.9%). Irrespective of growth phase, increases in dietary CC inclusion led to a linear increase (P<0.001) in the proportion of ALA in breast, thigh, and liver (76, 128, 288%, respectively), but not in brain tissue. An increase in dietary CC inclusion led to a linear increase (P<0.001) in the proportion of long-chain n-3 PUFAs, including docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA) in liver (109 and 80%, respectively) and brain (24 and 6%, respectively) tissue. However, in breast and thigh tissue, increases in dietary CC inclusion led to an increase in only (P<0.005) DPA (24 and 27%, respectively). The predominant n-3 PUFA in liver and brain tissue feeding 24% CC was DHA (48% and 88%, respectively), unlike in breast and thigh meat, where ALA increased (65 and 86%, respectively). The labeling claim requirement for n-3 PUFA enrichment (300 mg/100 g meat) was exceeded in breast and thigh by feeding a 24% CC diet for 28 d or 16% CC diet for 42 d, respectively.
Asunto(s)
Fenómenos Fisiológicos Nutricionales de los Animales , Brassicaceae/química , Pollos/metabolismo , Dieta/veterinaria , Ácidos Grasos Omega-3/metabolismo , Alimentación Animal/análisis , Animales , Pollos/crecimiento & desarrollo , Masculino , Especificidad de Órganos , Factores de TiempoRESUMEN
Energy and nutrient digestibility of solvent-extracted canola meal (CM) is limited in pigs by its relatively high fiber content. The seed hull, which greatly contributes to the fiber content of CM, is denser than the oil-free cotyledon. By utilizing streams of air, air classification partially separates these seed components on the basis of their different sizes and densities to produce a low-fiber, light-particle fraction and a high-fiber, heavy-particle fraction. Compared with parent CM, ADF and NDF were reduced by 31.9% and 29.5% in the light-particle fraction and were enriched by 16.5% and 9.0% in the heavy-particle fraction (DM basis), respectively. Particle size was 638, 18.9, and 76.1 µm for the parent CM and light- and heavy-particle fractions, respectively. To determine the nutrient digestibility of CM and their air-classified fractions, Brassica napus and B. juncea CM and their 2 air-classified fractions were evaluated in a 2 × 3 factorial arrangement together with a basal diet and an N-free diet. The experiment was conducted as an 8 × 8 Latin square in which diets contained 40% B. napus or B. juncea CM or their air-classified fractions and 60% basal diet. Digesta data from pigs fed the N-free diet served to subtract basal endogenous AA losses. Eight ileal-cannulated barrows (32 kg initial BW) were fed the 8 diets at 2.7 times maintenance DE for eight 11-d periods. At the end of each period, feces were collected for 48 h, and ileal digesta were collected for two 12-h periods. The DE and calculated NE values and the apparent total tract digestibility (ATTD) of GE were 6.3%, 10.0%, and 7.8% greater (P < 0.001) for B. juncea CM than for B. napus CM; 6.1%, 10.8%, and 5.3% greater (P < 0.001) for the light-particle fraction than for parent CM; and 5.4%, 7.2%, and 3.8% lower (P < 0.001) for the heavy-particle fraction than for parent CM, respectively. The standardized ileal digestibilities (SID) of His, Ile, Val, Asp, and Tyr were greater (P < 0.05) for B. juncea CM than for B. napus CM. The SID of CP and AA were greater (P < 0.01) in the light-particle fraction than in the heavy-particle fraction. The SID of Trp, Glu, Pro, and Tyr were greater (P < 0.05) in the light-particle fraction than in parent CM. In conclusion, B. juncea CM had greater energy and AA digestibility than B. napus CM because of reduced fiber content. Air classification of CM increased its energy and AA digestibility in the light-particle fraction for pigs because of the reduced dietary fiber content and decreased particle size.
Asunto(s)
Fenómenos Fisiológicos Nutricionales de los Animales/fisiología , Brassica napus , Dieta/veterinaria , Alimentos , Íleon/metabolismo , Planta de la Mostaza , Porcinos/metabolismo , Aire , Alimentación Animal , Animales , Digestión/fisiología , Metabolismo Energético/fisiología , Tamaño de la Partícula , Extractos Vegetales/metabolismo , Solventes , Porcinos/crecimiento & desarrolloRESUMEN
This study tested the ability of near infrared reflectance spectroscopy (NIRS) to estimate the fatty acid (FA) composition and iodine value (IV) of backfat from carcasses of pigs fed reduced-oil corn dried distillers grains with solubles. NIRS was suitable for screening purposes for the proportions of total saturated, monounsaturated, polyunsaturated, n-3 and n-6 FAs and some individual FAs such as C16:0, C18:1, C18:2n-6 and C18:3n-3 (R(2)=0.80-0.89; RMSECVs, root mean square errors of cross-validation=0.21-1.37% total FA) in both cold and warm intact backfat samples. This technology also met the requirements for a quick screening for the backfat IV in both cold and warm intact samples (R(2)=0.90 and 0.87; RMSECVs=1.66 and 1.80% total FA, respectively), which would help provide differential feed-back to pig producers and the feed industry and may provide the opportunity for breeding pigs for a desirable fat quality.
Asunto(s)
Tejido Adiposo , Alimentación Animal , Grano Comestible , Ácidos Grasos/química , Yodo/metabolismo , Espectroscopía Infrarroja Corta , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/métodos , Dieta/veterinaria , Ácidos Grasos/análisis , Femenino , Masculino , Porcinos , Zea maysRESUMEN
Immature green canola seed (full-fat green canola seed [FFGC]) is rejected by canola crushing plants due to chlorophyll staining of oil destined for human consumption. With >35% oil, FFGC can contribute energy to pig diets. The nutritive value of FFGC for growing-finishing pigs was determined in 2 studies. In Exp. 1, 6 ileal-cannulated barrows (46.5 kg BW) were fed 3 diets as a replicated 3 × 3 Latin square to determine standardized ileal digestible (SID) coefficients of AA and calculate DE and NE values for FFGC. A diet including 40% FFGC replaced wheat in a basal diet and a cornstarch-based N-free diet were fed to determine energy and nutrient digestibility by difference and to estimate basal endogenous AA losses to calculate SID of AA. In Exp. 2, 1,100 pigs (32.9 kg BW), housed in 50 pens of 22 barrows or gilts per pen, were fed 5 diets including 0, 5, 10, and 15% constant or declining amounts (15, 10, 5, 0, and 0%, respectively) of FFGC over 5 phases to determine effects of feeding FFGC on growth performance and carcass characteristics. Phase diets were formulated to provide 4.00, 3.60, 3.25, 2.90, and 2.65 g SID Lys/Mcal NE for d 0 to 21, d 22 to 42, d 43 to 62, d 63 to 74, and d 75 to 123 kg market weight. Carcass characteristics were measured using the Destron grading system. On DM basis, FFGC contained 43% ether extract, 25% CP, 22% NDF, 10 µmol/g glucosinolates, 1.35% Lys, 0.5% Met, 0.9% Thr, and 0.27% Trp. In FFGC, SID coefficients of Lys, Met, Thr, and Trp were 86.9, 87.3, 76.9, and 84.3%, respectively, and calculated DE and NE values were 4.92 and 3.50 Mcal/kg of DM, respectively. Overall, increasing dietary FFGC inclusion from 0 to 15% linearly decreased (P < 0.05) G:F, carcass weight, and dressing percentage (0.392 to 0.381 kg/kg, 96.7 to 95.7 kg, and 78.4 to 77.8%, respectively) and tended to decrease (P = 0.078) ADG. Pigs fed decreasing amounts of FFGC by growth phase compared with controls (0% FFGC) had lower (P = 0.011) overall G:F (0.392 vs. 0.372 kg/kg). Increasing dietary FFGC inclusion did not affect carcass backfat thickness and loin depth. The FFGC was a good source of dietary energy and AA. However, increasing dietary FFGC inclusion for pigs reduced G:F and dressing percentage likely because of the increased dietary fiber content, resulting from increasing FFGC and barley and reducing wheat, soybean meal, and tallow in diets. Inclusion of FFGC in swine diets should, therefore, be based on targeted G:F and relative cost to other feedstuffs.
Asunto(s)
Alimentación Animal/análisis , Brassica napus/química , Dieta/veterinaria , Grasas de la Dieta/metabolismo , Valor Nutritivo , Semillas/química , Sus scrofa/crecimiento & desarrollo , Animales , Peso Corporal/fisiología , Hordeum/química , Íleon/química , PorcinosRESUMEN
Nutrient digestibility in distillers dried grains with solubles (DDGS) is limited by constraints such as particle size and fiber. Wheat DDGS contains more fiber than corn DDGS that may reduce its nutritional value in swine feeds. Dry fractionation may create DDGS fractions with low and high fiber content; therefore, wheat DDGS was processed sequentially using a vibratory sifter and gravity table. Sufficient material was obtained from 3 wheat DDGS fractions that differed in particle size from fine to coarse (Fraction A [FA], Fraction C [FC], and Fraction D [FD]). Five cornstarch-based diets were mixed that contained either 40% wheat DDGS, 30% FA, 30% FC plus 10% soybean meal (SBM), 30% FD plus 15% SBM, or 35% SBM. A sixth, N-free diet served to subtract basal endogenous AA losses and as control for energy digestibility calculations. Six ileal-cannulated barrows (29 kg BW) were fed 6 diets at 2.8 times maintenance for DE in six 9-d periods as a 6 × 6 Latin square. Feces and ileal digesta were collected sequentially for 2 d each. Wheat DDGS FA, FC, and FD were 258, 530, and 723 µm in mean particle size and contained 44.8, 39.3, and 33.8% CP and 29.1, 35.1, and 37.5% in NDF, respectively. The apparent total tract digestibility (ATTD) of GE was greater (P < 0.05) for SBM than wheat DDGS, was greater (P < 0.05) for FA than wheat DDGS, and did not differ between FC, FD, and wheat DDGS. The standardized ileal digestibility (SID) did not differ between SBM and wheat DDGS (P > 0.05) for most AA. The SID of Arg, Lys, Trp, and available Lys was greater (P < 0.05) for FD than wheat DDGS but was similar for FA, FC, and wheat DDGS and was greater (P < 0.05) for FD than SBM. The DE and NE value was greater (P < 0.05) for SBM, FA, and FC than wheat DDGS and did not differ between FD and wheat DDGS. The SID content of indispensable AA and available Lys was greater (P < 0.05) for SBM than wheat DDGS. The SID content of Ile, Leu, Met, Phe, and Val was greater (P < 0.05) for FA than wheat DDGS but did not differ for indispensable AA between FC and wheat DDGS. The SID content of His, Ile, Leu, Met, and Phe was lower (P < 0.05) for FD than wheat DDGS. In conclusion, dry fractionation creates DDGS fractions with a differing chemical composition. Fine particle fractions contain less fiber and more CP than coarse particle fractions, but their AA digestibility was lower, likely due to most of the solubles being fine particles that are more susceptible to AA damage than protein entrapped in particles of larger size.
Asunto(s)
Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Digestión/fisiología , Grano Comestible/química , Sus scrofa/fisiología , Aminoácidos/metabolismo , Animales , Fibras de la Dieta/análisis , Heces/química , Íleon/metabolismo , Valor Nutritivo , Glycine max/metabolismo , Porcinos , Triticum/química , Zea mays/químicaRESUMEN
Sustained price increases for traditional cereal grain and protein meal feed commodities have forced the pork industry to consider the dietary inclusion of alternative feedstuffs. Crop seed may serve as feedstuffs but their demand as feedstock for human food, biofuel, and bioindustrial products has increased. Together with these products, coproducts such as distillers dried grains with solubles, wheat millrun, and canola meal are produced. As omnivores, pigs are ideally suited to convert these non-human-edible coproducts into high-quality food animal protein. Therefore, coproducts and other low-cost alternative feedstuffs such as pulses and oilseeds can be included in pig diets to reduce feed cost per metric ton of feed. However, inclusion of alternative feedstuffs in pig diets does not necessarily reduce feed cost per kilogram of gain. Therefore, the use of novel and existing feedstuffs in pig diets must be optimized following their characterization for energy and AA profile. Alternative feedstuffs generally have a high content of at least 1 of the following antinutritional factors (ANF): fiber, tannins, glucosinolates, and heat-labile trypsin inhibitors. Several methods can optimize nutrient use of pigs fed alternative feedstuffs by reducing effects of their ANF. These methods include 1) particle size reduction to increase nutrient digestibility, 2) dehulling or scarification to reduce tannin and fiber content of pulses and oilseeds, 3) air classification to create fractions that have a greater content of nutrients and lower content of ANF than the feedstock, 4) heat treatments such as extrusion, toasting, roasting, and micronization to reduce heat-labile ANF, 5) dietary supplementation with fiber-degrading enzymes or predigestion of fibrous feedstuffs or diets with fiber-degrading enzymes to increase dietary nutrient availability, and 6) formulation of diets based on bioavailable AA coefficients. In conclusion, the feeding of alternative ingredients may reduce feed cost per unit of pork produced provided that their price per unit NE or digestible lysine is less than that of the traditional feedstuffs and that negative effects of their ANF are controlled.
Asunto(s)
Alimentación Animal/análisis , Alimentación Animal/economía , Dieta/economía , Dieta/veterinaria , Porcinos/fisiología , Fenómenos Fisiológicos Nutricionales de los Animales , AnimalesRESUMEN
A study was conducted to determine the standardized ileal digestibility (SID) of AA and calculate the NE value for regular-oligosaccharide, micronized full-fat soybean (R-MFFSB), low-oligosaccharide, micronized full-fat soybean (LO-MFFSB), lentil, and enzymatically hydrolyzed casein (EHC) for growing pigs. Six ileal-cannulated barrows (31.4 kg BW) were fed 6 diets in a 6 × 6 Latin square. Five diets were cornstarch based, containing either soybean meal (SBM), R-MFFSB, LO-MFFSB, or EHC as sole protein source or N free. The sixth diet contained lentil as sole protein and energy source. The SID of AA for diets was calculated using the N-free diet. Digestibility of AA in feedstuffs was determined by the direct method. Energy digestibility in SBM, R-MFFSB, and LO-MFFSB was determined by difference from the N-free diet whereas energy digestibility in lentil was determined by the direct method. On DM basis, SBM, R-MFFSB, LO-MFFSB, and lentil contained 52, 43, 43, and 27% CP, 8, 12, 14, and 16% NDF, and 1.8, 19, 21, and 1.6% ether extract, respectively. The SID of Lys for SBM was greater (P < 0.05) than that for R-MFFSB or LO-MFFSB (76 vs. 79 and 79%). The SID of other indispensable AA (except Trp) for SBM was also greater (P < 0.05) than that for R-MFFSB or LO-MFFSB. The R-MFFSB and LO-MFFSB were similar in SID of AA. The SID of Lys for lentil (81%) was lower (P < 0.05) than that for SBM with a similar trend for SID of other indispensable AA except for Met and Thr whose SID was similar to SBM. The SID of AA for EHC ranged from 98 to 112%. The SBM had a lower (P < 0.05) NE value than R-MFFSB or LO-MFFSB (2.63 vs. 2.95 and 3.00 Mcal/kg DM). Lentil and SBM were similar in NE value (2.60 vs. 2.63 Mcal/kg DM). In conclusion, R-MFFSB and LO-MFFSB were similar in energy and AA value for pigs. Lentil had lower SID of AA than SBM. However, lentil and SBM were similar in NE value; therefore, lentil can serve as alternative pulse feedstuff for pigs. The AA in EHC were mostly completely digested indicating that EHC can be fed to estimate ileal endogenous AA losses.
Asunto(s)
Aminoácidos/metabolismo , Digestión , Metabolismo Energético , Íleon/fisiología , Sus scrofa/fisiología , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Calorimetría/veterinaria , Caseínas/metabolismo , Cromatografía Líquida de Alta Presión/veterinaria , Dieta/veterinaria , Lens (Planta)/química , Masculino , Oligosacáridos/metabolismo , Glycine max/química , Espectrofotometría/veterinaria , Sus scrofa/crecimiento & desarrolloRESUMEN
Dietary inclusion of co-products (Co-P) provides opportunities for diversifying the feedstuff matrix by using local feedstuffs, reducing feed costs, and producing value-added pork. In 2 studies, we determined effects of Co-P (canola meal, distillers dried grains with solubles, and co-extruded oil seed and field pea) inclusion level and reduced dietary CP concentration on growth performance, carcass characteristics, and jowl fatty acid profiles of growing-finishing pigs. Pigs were fed isoenergetic and isolysinic diets over 4 growth phases with 8 pen observations per dietary regimen. At slaughter, carcasses were characterized for all pigs and jowl fat was collected from 2 pigs per pen. In Exp. 1, 1,056 pigs (initial BW, 35.3 ± 0.4 kg) were fed 3 levels of dietary Co-P (low, mid, and high) and 2 CP concentrations (low and normal). Overall (d 0 to 86), increasing Co-P inclusion from low to mid or high decreased (P < 0.001) ADFI and ADG of pigs. Low CP concentration increased (P < 0.05) ADFI and ADG compared with normal CP concentration. An interaction (P = 0.026) occurred between dietary Co-P inclusion and CP concentration for G:F; low CP reduced (P < 0.05) G:F compared with normal CP for pig fed low Co-P, but G:F did not differ between CP concentrations for pigs fed mid and high Co-P. Increasing dietary Co-P inclusion from low to high increased (P < 0.001) α-linolenic acid (ALA) in jowl fat but decreased (P < 0.001) carcass weight and loin depth. In Exp. 2, 1,008 pigs (initial BW, 30.3 ± 0.4 kg) were assigned to 5 dietary regimens with Co-P increasing from 2.0 to 50.0% or a sixth regimen with 10% extra supplemental AA for the 37.5% Co-P diet. Overall (d 0 to 97), increasing Co-P inclusion did not affect ADFI, ADG, and G:F. Increasing dietary Co-P inclusion linearly decreased (P < 0.01) carcass weight, dressing percentage, backfat thickness, and loin depth but linearly increased (P < 0.001) jowl ALA. Supplementing 10% extra AA to the 37.5% Co-P diet did not affect growth performance or dressing percentage but increased (P = 0.014) carcass leanness and decreased (P = 0.023) backfat thickness compared with the 37.5% Co-P diet, indicating that dietary AA supply did not limit BW gain. In conclusion, Co-P can be included by up to 50% in diets for growing-finishing pigs without affecting G:F. However, increasing dietary Co-P may reduce ADG, ADFI, and carcass weight even if diets are balanced for dietary NE and standardized ileal digestible AA content.
Asunto(s)
Alimentación Animal/análisis , Dieta/veterinaria , Carne/análisis , Sus scrofa/fisiología , Aminoácidos/administración & dosificación , Aminoácidos/metabolismo , Animales , Composición Corporal , Peso Corporal , Proteínas en la Dieta/metabolismo , Suplementos Dietéticos/análisis , Relación Dosis-Respuesta a Droga , Ácidos Grasos/metabolismo , Ácidos Grasos Omega-3/metabolismo , Femenino , Lino/metabolismo , Masculino , Especificidad de Órganos , Distribución Aleatoria , Semillas/metabolismo , Sus scrofa/genéticaRESUMEN
Inclusion of conventional dark-seeded (Brassica napus) and novel yellow-seeded (Brassica juncea) canola meal (CM) can potentially replace soybean (Glycine max) meal (SBM) in pig diets. Our objective was to examine the preference of weaned pigs fed diets containing SBM or B. napus or B. juncea CM and to compare it against previously reported growth performance data (Exp. 1 and 2). In Exp. 1 and 2, growth performance was evaluated using 220 and 240 weaned pigs, respectively, by replacing dietary SBM with up to 20% B. napus (Exp. 1) or 24% B. juncea CM (Exp. 2). Feeding up to 20% B. napus CM to pigs did not affect growth performance, but increasing inclusion of B. juncea CM linearly reduced (P < 0.001) ADFI, ADG, and G:F most likely due to the higher content of glucosinolates, particularly gluconapin in B. juncea CM as confirmed by principle component analysis. In Exp. 3 and 4, SBM and B. napus and B. juncea CM fed at 20% dietary inclusion were evaluated in 2 preference studies using 216 and 144 pigs of 35 d of age, respectively. Pens equipped with 2 feeders housed 8 or 4 pigs per pen, in Exp. 3 and 4, respectively. Diets formulated to equal NE and standardized ileal digestible AA were offered in a paired choice as mash (Exp. 3) or pellets (Exp. 4) for 3 consecutive 7-d periods (3 d nontest and 4 d preference test). The 3 treatments offered were (i) SBM vs. B. napus CM, (ii) SBM vs. B. juncea CM, and (iii) B. napus vs. B. juncea CM. Pigs preferred SBM (P < 0.001) over B. napus and B. juncea CM diets, and pigs preferred B. napus (P < 0.001) over B. juncea CM diet. High content of the glucosinolate gluconapin likely reduced feed preference in B. juncea more than in B. napus CM. In conclusion, the contrast between preference and performance studies feeding CM to pigs indicates that preference studies should be interpreted cautiously until validated by growth performance data.
Asunto(s)
Alimentación Animal/análisis , Brassica napus/química , Preferencias Alimentarias , Planta de la Mostaza/química , Porcinos/crecimiento & desarrollo , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/veterinaria , Análisis de Componente Principal , Solventes , Porcinos/fisiologíaRESUMEN
Yellow-seeded Brassica juncea is a novel canola species targeted to grow in the southern Canadian prairies where thermotolerance, disease resistance, and adaptation to dry agronomic conditions are required. The support of its cultivation needs nutritional evaluation of its coproduct. The B. juncea canola meal (CM) contains less fiber than conventional, dark-seeded Brassica napus CM but also slightly less Lys. In a 6 × 6 Latin square, 6 distal ileum cannulated pigs (47 kg BW) were fed 6 diets to determine the apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of CP and AA, AID and apparent total tract digestibility (ATTD) of energy, and VFA content in digesta and feces. Pigs were fed 6 diets: basal [46% wheat (Triticum aestivum) and corn (Zea mays) starch], 4 diets with 46% wheat and either B. juncea or B. napus CM at 25 or 50%, and a N-free diet based on corn starch. The B. juncea CM had higher (P < 0.05) ATTD of energy than B. napus CM (68.6 vs. 60.3%) likely due to its lower fiber content. Ileal total VFA was lower (P < 0.001) in pigs fed B. juncea than B. napus CM diets. In pigs fed B. juncea CM, the molar ratio in digesta was lower (P < 0.001) for acetate and butyrate whereas the propionate ratio was lower (P < 0.001) in feces than in pigs fed B. napus CM diets. The CM species did not affect the AID of energy, SID of AA, and feces VFA content. The DE value was higher (P < 0.05) and content of SID Lys was lower (P < 0.05) for B. juncea than B. napus CM. In conclusion, availability of B. juncea CM, a coproduct of a canola species grown in Canadian prairie land, will increase flexibility in swine feed formulation.
Asunto(s)
Aminoácidos/metabolismo , Alimentación Animal/análisis , Brassica napus/química , Digestión/fisiología , Planta de la Mostaza/química , Porcinos/fisiología , Aminoácidos/química , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/veterinaria , Ingestión de Energía , Íleon/fisiología , Masculino , Especificidad de la Especie , Porcinos/crecimiento & desarrolloRESUMEN
Cold-pressed canola cake is a coproduct of biodiesel production that contains more residual oil than expeller-pressed and solvent-extracted canola meal. Cold-pressed canola cake might be an attractive feedstuff for swine due to local availability from small plants. However, the nutritional quality and content of anti-nutritional factors of cold-pressed canola cake are poorly defined and vary with processing conditions. This experiment evaluated cold-pressed canola cake processed using 4 different conditions: a nonheated and heated barrel at slow and fast screw speed in a 2 × 2 factorial arrangement. Seven ileally cannulated barrows (26 kg of BW) were fed twice daily at 2.8 × maintenance diets containing either 44% of 1 of the 4 cold-pressed canola cake samples, expeller-pressed canola meal, canola seed, or an N-free diet in a 7 × 7 Latin square. The objectives were to measure the energy and AA digestibility and to calculate standardized ileal digestible (SID) AA and NE content. Each 9-d experimental period consisted of a 5-d diet adaptation, followed by 2-d feces and 2-d ileal digesta collections, and 7 observations per diet were obtained. Cold-pressed canola cake contained 41% CP, 16% ether extract, and 5 µmol of total glucosinolates/g (DM basis). Both apparent ileal digestibility (AID) and total tract energy digestibility of energy in cold-pressed canola cake was 36% greater (P < 0.05) in heated vs. nonheated conditions and 8% greater (P < 0.05) in fast vs. slow screw speed without interaction, indicating that heat enhanced energy digestibility. The AID of energy of cold-pressed canola cake was 13 and 118% greater (P < 0.01) than expeller-pressed canola meal and canola seed, respectively. Heat and speed interacted (P < 0.05) for SID of AA of test ingredients, but effects were not consistent among AA. The DE and calculated NE content of cold-pressed canola cake was 0.73 and 0.52 Mcal/kg greater (P=0.001; DM basis), respectively, than expeller-pressed canola meal and did not differ from canola seed. Cold-pressed canola cake averaged 4.17 Mcal of DE/kg, 2.84 Mcal of NE/kg, 0.87% SID Lys, 0.46% SID Met, and 0.79% SID Thr (DM basis). In conclusion, processing conditions greatly affected the digestible nutrient content of cold-pressed canola cake. Content of residual ether extract was an important determinant of the energy value of cold-press canola cake, whereas residual glucosinolates did not seem to hamper nutrient digestibility.
Asunto(s)
Alimentación Animal/análisis , Brassica rapa/química , Brassica rapa/metabolismo , Dieta/veterinaria , Digestión/fisiología , Porcinos/fisiología , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Manipulación de Alimentos/métodos , Masculino , Valor Nutritivo , Semillas/química , Semillas/metabolismoRESUMEN
Nutrient digestibility in distillers dried grains with solubles (DDGS) is limited by physical constraints such as particle size and by biochemical limitations such as phytate and fiber or nonstarch polysaccharides (NSP). To determine the separate effects of these limitations on nutrient digestibility, ground DDGS (383 µm) supplemented with phytase (0 or 250 units/kg of feed) and xylanase (0 or 4,000 units/kg of feed) was evaluated in a 2 × 2 factorial arrangement of treatments together with unground DDGS (517 µm) and an N-free diet in a 6 × 6 Latin square. Cofermented wheat and corn DDGS contained 8.6% moisture, 31.0% CP, 1.04% Lys, 8.0% ether extract, 2.0% starch, 40% NDF, and 0.85% P (as-is basis). Diets contained 43.7% DDGS as the sole source of AA; the digesta from pigs fed the N-free diet served to subtract basal endogenous AA losses and as control for energy digestibility. Six ileal-cannulated barrows (37.1 ± 0.8 kg of BW) were fed 6 diets at 2.8 × maintenance for DE in six 9-d periods. Feces and ileal digesta were collected for 2 d each. The apparent ileal digestibility (AID) of GE and apparent total tract digestibility (ATTD) of GE and NDF were 2.3, 0.5, and 5.1%-units greater (P < 0.05) for the ground than unground DDGS diet, respectively. Consequently, the ATTD of GE was 1.3%-units greater (P < 0.05) and the DE content was 0.06 Mcal/kg greater (P < 0.05) for ground than unground DDGS, respectively. Grinding of DDGS did not affect (P > 0.05) the ATTD of crude fiber, ADF, P, and Ca in diets. Grinding of DDGS increased (P < 0.05) the AID of most AA in diets including Lys, Met, and Thr by 6.9, 1.1, and 1.7%-units, respectively. Grinding of DDGS increased (P < 0.05) the SID of Lys by 6.2%-units and SID content of Lys and Thr by 0.06 and 0.02%-units, respectively. Phytase and xylanase did not interact (P > 0.05) to affect nutrient digestibility. Phytase increased (P < 0.001) the ATTD of P by 10.5%-units, but did not affect (P > 0.05) AA digestibility. Xylanase did not affect nutrient digestibility. In conclusion, particle size is an important physical characteristic affecting digestibility of energy and AA, but not P in DDGS. Phytate in DDGS limits digestibility of P, but not energy and AA. The substrate for xylanase in DDGS did not hinder energy and AA digestibility.