Energy concentration and phosphorus digestibility in whey powder, whey permeate, and low-ash whey permeate fed to weanling pigs

Two experiments were conducted to determine DE and ME, the apparent total tract digestibility (ATTD) of P, and the standardized total tract digestibility (STTD) of P in whey powder (3,646 kcal/kg), whey permeate (3,426 kcal/kg), and low-ash whey permeate (3,657 kcal/kg) fed to weanling pigs. The DE and ME in the 3 whey products were determined using 32 barrows (9.2 ± 0.4 kg of BW). A basal diet based on corn, soybean meal, and fish meal and 3 diets containing 70% of the basal diet and 30% of each whey product were prepared. Each diet was fed to 8 pigs that were housed individually in metabolism cages. The total collection method was used for fecal and urine collections with 5-d adaptation and 5-d collection periods, and the difference procedure was used to calculate DE and ME in the 3 whey products. The concentrations of DE in whey powder and low-ash whey permeate were greater (P < 0.001) than in whey permeate (3,646 and 3,683 vs. 3,253 kcal/kg of DM). The concentrations of ME in whey powder and low-ash whey permeate were also greater (P < 0.001) than in whey permeate (3,462 and 3,593 vs. 3,081 kcal/kg of DM). The ATTD and STTD of P in the 3 whey products were determined using 32 barrows (11.0 ± 0.81 kg of BW). Three cornstarch-sucrose-based diets containing 30% of each whey product as the sole source of P were prepared. A P-free diet that was used to estimate the basal endogenous losses of P was also formulated. The ATTD of P in whey powder and in whey permeate was greater (P < 0.001) than in low-ash whey permeate (84.3 and 86.1 vs. 55.9%), but the STTD values for P were not different among the 3 ingredients (91.2, 93.1, and 91.8% in whey powder, whey permeate, and low-ash whey permeate, respectively). In conclusion, whey permeate contains less GE, DE, and ME than whey powder and low-ash whey permeate, but all 3 ingredients have an excellent digestibility of P.     

Digestibility of energy and phosphorus in ten samples of distillers dried grains with solubles fed to growing pigs

An experiment was conducted to measure DE and ME and the apparent total tract digestibility (ATTD) of energy, N, and P in distillers dried grains with solubles (DDGS) fed to growing pigs. Ten sources of DDGS were obtained from ethanol plants in South Dakota and Minnesota, and 11 diets were formulated. One diet was based on corn (96.8%), limestone, salt, vitamins, and microminerals. Ten additional diets were formulated by mixing the corn diet and each of the 10 sources of DDGS in a 1:1 ratio. Eleven growing pigs (initial BW of 29.3 +/- 0.42 kg) were allotted to an 11 x 11 Latin square design, with 11 periods and 11 pigs. Each of the 11 diets was fed to each pig during 1 period. Pigs were placed in metabolism cages that allowed for the total, but separate, collection of feces and urine. Samples were analyzed for GE, N, and P and energy and N balances, and the ATTD of GE, N, and P were calculated for each diet. By subtracting the contribution from the corn diet to the DDGS-containing diets, the energy and N balances and the ATTD for GE, N, and P for each source of DDGS were calculated. Results of the experiment showed that the DE and ME differed (P < 0.001) among the 10 sources of DDGS (3,947 to 4,593 kcal of DE/kg of DM and 3,674 to 4,336 kcal of ME/kg of DM). The average DE and ME in DDGS were 4,140 and 3,897 kcal/kg of DM, respectively. These values were not different from the DE and ME in corn (4,088 and 3,989 kcal/kg of DM, respectively). Based on the analyzed GE and nutrient composition of DDGS and the calculated values for DE and ME, prediction equations for DE and ME were developed. These equations showed that DE and ME in DDGS may be predicted from the concentration of ash, ether extract, ADF, and GE. The retention of N from DDGS was greater (P < 0.001) than from corn, but when calculated on a percentage basis, the N retention did not differ between DDGS and corn. The ATTD of P in DDGS was 59.1% on average for the 10 samples. This value was greater (P < 0.001) than the ATTD of P in corn (19.3%). It is concluded that the DE and ME in DDGS is not different from the DE and ME in corn. However, if DDGS is included in diets fed to growing swine, a greater portion of the organic P will be digested and absorbed, thus reducing the need for adding inorganic P to the diets.     

Comparison of digestible and metabolizable energy and digestible phosphorus and amino acid content of corn ethanol coproducts from Brazil and the United States produced using fiber separation technology for swine

Three experiments (exp.) were conducted to determine and compare the digestibility of nutrients and energy of corn distillers dried grains with solubles (DDGS) from the United States (USDDGS), a dried mixture of corn bran with solubles (CBS) from Brazil (BRCBS), and high protein corn distillers dried grains (HP-DDG) from the United States (USHPDG) and Brazil (BRHPDG) in growing pigs. The feed ingredients were evaluated for apparent total tract digestibility (ATTD) of gross energy (GE), dry matter (DM), crude protein (CP), ether extract, neutral and acid detergent fiber (NDF and ADF, respectively), and digestible and metabolizable energy (DE and ME, respectively) using the total collection and index methods in exp. 1; ATTD and standardized total tract digestibility (STTD) of phosphorus (P) in exp. 2; and apparent (AID) and standardized (SID) ileal digestibilities of CP and amino acids (AA) in exp. 3. Fifty crossbred barrows (32.4 ± 6.9, 38.3 ± 5.2, and 46.2 ± 5.3 kg body weight [BW], in exp. 1, 2, and 3, respectively) were fed a corn basal diet in exp. 1, a P-free diet in exp. 2, and an N-free diet in exp. 3 or diets with 40% inclusion of test ingredients to provide 10 replications per treatment. Pigs were housed individually in metabolism cages (exp. 1) or in pens (exp. 2 and 3) and fed at 2.8 times the maintenance DE requirement (110 kcal/kg BW^0.75) based on their BW at the beginning of each experiment. Except for ATTD of NDF, which tended (P = 0.058) to be greater by the index method compared with the total collection method, no difference between the total collection and index methods was observed for ATTD of remaining nutrients and DE. The ATTD of DM, GE, NDF, and DE content of BRHPDG were greater (P < 0.001) than USHPDG, BRCBS, and USDDGS. The AID of CP, Arg, His, Ile, Leu, Lys, Thr, and Val and the SID of His, Leu, Lys, and Val of BRHPDG were 8% to 36% greater (P < 0.05) than those from USHPDG. Except for Trp, all AID and SID AA values were greater (P < 0.05) in BRHPDG than in USHPDG. The ATTD of DM, GE, NDF, and ADF; DE and ME content; AID of CP, Arg, Ile, Leu, Phe, Thr, and Trp; and SID of CP, Arg, Phe, and Thr of USDDGS were 9% to 45% greater (P < 0.05) than those in BRCBS. The ATTD and the STTD of P in USHPDG and USDDGS were 26% to 42% greater (P < 0.05) compared with BRHPDG and BRCBS. In conclusion, BRHPDG had a greater digestibility of energy and most of the AA than USHPDG, while the BRCBS evaluated had lower nutritional value than the USDDGS source.     

Digestible and metabolizable energy concentrations and amino acid digestibility of dried yeast and soybean meal for growing pigs

Energy values and amino acid (AA) digestibility of dried yeast (DY) and soybean meal (SBM) were determined in 2 experiments with growing pigs. Experiment 1 was conducted to determine the digestible energy (DE) and metabolizable energy (ME) in DY and SBM. Thirty barrows with a mean initial body weight (BW) of 20.6 kg (SD = 1.04) were assigned to 5 dietary treatments in a randomized complete block design with period and BW as blocking factors. A reference diet was prepared with corn, canola meal, and soybean oil as energy-contributing ingredients. Four additional diets were prepared by adding 5% and 10% DY or SBM at the expense of energy-contributing ingredients in the reference diet. The ratio of corn, canola meal, and soybean oil was kept consistent across the experimental diets. Each experimental period consisted of 5-d adaptation and 5-d quantitative collection of feces and urine. Test ingredient-associated DE or ME intake (kcal/d) was regressed against test ingredient intake [kg dry matter (DM)/d] to estimate the DE or ME in test ingredients as the slope of linear regression model. The DE in DY was estimated at 3,933 kcal/kg DM, which was not different from the estimated DE in SBM at 4,020 kcal/kg DM. Similarly, there was no difference between DY and SBM in the estimated ME (3,431 and 3,756 kcal/kg DM, respectively). Experiment 2 was conducted to determine the standardized ileal digestibility (SID) of AA in DY and SBM. Twenty-one barrows with a mean initial BW of 20.0 kg (SD = 1.31) were surgically fitted with T-cannulas at the distal ileum and assigned to 3 dietary treatments in a randomized complete block design with BW as a blocking factor. Two semi-purified diets containing DY or SBM as the sole nitrogen source and one nitrogen-free diet (NFD) were prepared. The NFD was used to estimate the basal ileal endogenous losses of CP and AA. Pigs were fed the 3 diets for 5 d as adaptation, followed by 2 d of feeding with ileal digesta collection. The SID of AA, except Gly and Pro, in DY was less (P < 0.05) than in SBM. The SID of indispensable AA in DY ranged from 64.1% for Thr to 85.2% for Arg, and those in SBM ranged from 83.9% for Thr to 91.8% for Arg. In conclusion, energy values of DY are not different from those of SBM, whereas AA in DY is less digestible than in SBM. The estimated DE and ME as well as the SID of AA in DY and SBM can be used in diet formulation for growing pigs using these ingredients.     

Phosphorus digestibility and energy concentration of enzyme-treated and conventional soybean meal fed to weanling pigs

Two experiments were conducted to determine the apparent total tract digestibility (ATTD) of P and the concentration of DE and ME in enzyme-treated soybean meal (SBM) and in conventional soybean meal (SBM-CV). Phosphorus digestibility in 2 enzyme-treated SBM (HP-310 and HP-340) and in SBM-CV was measured using 36 barrows (initial BW: 21.9 ± 1.1 kg) that were housed in metabolism cages and randomly allotted to 6 diets with 6 replicates per diet. During production, HP-310 had been treated with an enzyme mixture containing no phytase, whereas HP-340 was treated with an enzyme mixture that contained exogenous phytase. Three diets containing HP-310, HP-340, or SBM-CV as the sole source of P were formulated. Three additional diets also contained HP-310, HP-340, and SBM-CV, but each of these diets was fortified with 500 units of microbial phytase. The ATTD of P in HP-310 and SBM-CV increased (P < 0.05) as phytase was included in the diet (from 59.8 to 77.7% for HP-310 and from 65.5 to 79.5% for SBM-CV), but the ATTD of P in HP-340 without and with phytase was not different (P > 0.05; 83.8 and 87.7%, respectively). There were no differences (P > 0.05) in the ATTD of P between HP-310 and SBM-CV, but the ATTD of P in HP-340 was greater (P < 0.05) than in the other 2 meals. The DE and ME in corn, 2 sources of enzyme-treated SBM (HP-200 and HP-310), and in SBM-CV were measured in the second experiment using 28 barrows housed in metabolism cages (initial BW: 16.8 ± 2.5 kg of BW). The process used to produce HP-200 is similar to that used to produce HP-310 except that HP-200 is exposed to the enzymes for a shorter period of time than HP-310. A corn-diet consisting of 96.45% corn and vitamins and minerals was formulated. Three additional diets were formulated by mixing corn and each source of SBM with vitamins and minerals. Pigs were randomly allotted to the 4 diets with 7 replicate pigs per diet, and urine and feces were collected quantitatively during the last 5 d of a 14-d feeding period. The concentration of DE in HP-200, HP-310, and SBM-CV was 4,333, 4,316, and 4,347 kcal/kg of DM, respectively. These values were not different (P > 0.05), but they were greater (P < 0.05) than the DE in corn (3,891 kcal/kg of DM). The concentration of ME was 3,780, 3,926, 3,914, and 3,980 kcal/kg of DM in corn, HP-200, HP-310, and SBM-CV, respectively. These values were not different (P > 0.05). It is concluded that enzyme treatment of SBM does not influence the digestibility of P or the concentration of DE and ME in the meals.     

Determination and prediction of digestible and metabolizable energy from chemical analysis of corn coproducts fed to finishing pigs

Twenty corn coproducts from various wet- and dry-grind ethanol plants were fed to finishing pigs to determine DE and ME and to generate equations predicting DE and ME based on chemical analysis. A basal diet comprised corn (97.05%), limestone, dicalcium phosphate, salt, vitamins, and trace minerals. Twenty test diets were formulated by mixing the basal diet with 30% of a coproduct, except for dried corn solubles and corn oil, which were included at 20 and 10%, respectively. There were 8 groups of 24 finishing gilts (n = 192; BW = 112.7 ± 7.9 kg). Within each group, gilts were randomly assigned to 1 of 5 test diets or the basal diet for a total of 4 replications per diet per group. Two groups of gilts were used for each set of coproducts, resulting in 8 replications per coproduct and 32 replications of the basal diet. The experiment was conducted as a completely randomized design. Gilts were placed in metabolism crates and offered 3 kg daily of their assigned test diet for 13 d, with total collection of feces and urine during the last 4 d. Ingredients were analyzed for DM, GE, CP, ether extract, crude fiber, NDF, ADF, total dietary fiber (TDF), ash, AA, and minerals, and in vitro OM digestibility was calculated for each ingredient. The GE was determined in the diets, feces, and urine to calculate DE and ME for each ingredient. The DE and ME of the basal diet were used as covariates among groups of pigs. The DE of the coproducts ranged from 2,517 kcal/kg of DM (corn gluten feed) to 8,988 kcal/kg of DM (corn oil), and ME ranged from 2,334 kcal/kg of DM (corn gluten feed) to 8,755 kcal/kg of DM (corn oil). By excluding corn oil and corn starch from the stepwise regression analysis, a series of DE and ME prediction equations were generated. The best fit equations were as follows: DE, kcal/kg of DM = -7,471 + (1.94 × GE) - (50.91 × ether extract) + (15.20 × total starch) + (18.04 × OM digestibility), with R(2) = 0.90, SE = 227, and P < 0.01; ME, kcal/kg of DM = (0.90 × GE) - (29.95 × TDF), with R(2) = 0.72, SE = 323, and P < 0.01. Additional equations for DE and ME included NDF in the instance that TDF data were not available. These results indicate that DE and ME varied substantially among corn coproducts and that various nutritional components can be used to accurately predict DE and ME in corn coproducts for finishing pigs.     

Chemical composition,energy and amino acid digestibility in double-low rapeseed meal fed to growing pigs

Background:The nutritional value of rapeseed meal may be variable due to the variation of its chemical composition.And a precise understanding of the nutritional value of an ingredient is beneficial for the accurate diet formulation and reduction of feed costs.This study was conducted to determine the chemical composition,digestible energy(DE) and metabolizable energy(ME) content,and apparent ileal digestibility(AID) and standardized ileal digestibility(SID) of amino acids(AA) for growing pigs.Thirteen solvent-extracted double-low rapeseed meal(DLRSM) samples were obtained from the main double-low rapeseed producing areas in China.Methods:The DE and ME contents of the 13 DLRSM samples were measured in growing pigs(six pigs per DLRSM sample,average initial body weight(BW) = 48.3 kg).The AID and SID of AA of 10 DLRSM samples were determined in 12 crossbred barrows(average initial BW = 35.3 kg) by using two 6x6 Latin square designs.Each Latin square comprised one N-free diet and 5 DLRSM test diets.Results:The chemical composition of DLRSM varied among samples,and the coefficient of variation was greater than 10%for ether extract(EE),neutral detergent fiber(NDF),acid detergent fiber(ADF),calcium(Ca),and total glucosinolates.The AA content of DLRSM varied among samples especially for lysine(Lys) and methionine(Met).On a dry matter(DM) basis,the apparent total tract digestibility(ATTD) of gross energy(GE),the DE and ME and the ME:DE ratio of DLRSM averaged 62.39%,2862 kcal/kg and 2723 kcal/kg,and 94.95%,respectively.The mean value of SID of Lys was 70.52% which varied from 66.54-76.54%.The SID of crude protein(CP),Met,and threonine(Thr) averaged 72.81%,82.41%,and 69.76%,respectively.Conclusions:There was great variability in chemical composition especially in the concentration of EE,NDF and ADF,but no significant differences in energy content of the DLRSM samples were observed.In addition,the AID and SID of all AA were relatively similar among DLRSM samples except for that of Lys.     

Energy and nutrient digestibility in NutriDense corn and other cereal grains fed to growing pigs

Two experiments were conducted to measure the energy and nutrient digestibilities in NutriDense corn and other cereal grains. An additional objective was to evaluate the effect of balancing diets with AA on the values measured for DE and ME of corn varieties. In Exp. 1, 6 growing pigs were fitted with a T-cannula in the distal ileum and allotted to a 6 x 6 Latin square design to measure apparent ileal digestibility (AID) and standardized ileal digestibility (SID) values for CP and AA in NutriDense corn, yellow dent corn, barley, wheat, and sorghum. Diets based on each of the 5 cereal grains were formulated, along with a N-free diet. Results of this experiment showed that the AID for most indispensable AA were greater (P < 0.05) in NutriDense corn and wheat than in the other cereal grains. The SID for Lys in NutriDense corn (77.6%) was greater (P < 0.05) than in yellow dent corn (68.5%), and sorghum (56.9%), but not different from wheat (75.1%) and barley (71.7%). The SID for Arg and Met in NutriDense corn also were greater (P < 0.05) than in yellow dent corn (88.1 and 87.2% vs. 84.5 and 82.8%, respectively). For the remaining indispensable AA, no differences in SID between NutriDense corn and yellow dent corn were observed. For all AA, the lowest values (P < 0.05) for AID and SID were obtained for sorghum. If calculated as grams of standardized ileal digestible AA per kilogram of DM, concentrations of all indispensable AA in NutriDense corn were greater (P < 0.05) than in yellow dent corn, but barley and wheat had greater concentrations of most AA than yellow dent corn and NutriDense corn. In Exp. 2, 12 growing barrows were placed in metabolism cages, and the DE and ME of NutriDense corn and yellow dent corn were measured. Both grains were used in diets without or with crystalline AA supplementation. Each diet was fed to 6 pigs in a 2-period, changeover design. The DE and the ME in NutriDense corn (4,004 and 3,922 kcal/kg of DM, respectively) were greater (P < 0.01) than in yellow dent corn (3,878 and 3,799 kcal/kg of DM, respectively). Values for DE and ME were not affected by the addition of crystalline AA to the diets. It is concluded that NutriDense corn has a greater value than yellow dent corn in diet formulations due to increased concentrations of digestible, indispensable AA and energy. However, barley and wheat have greater concentrations, whereas sorghum has lower concentrations, of many digestible AA than NutriDense corn.     

Assessment of the feeding value of South Dakota-grown field peas (Pisum sativum l.) for growing pigs

Four experiments were conducted to investigate the feeding value of South Dakota-grown field peas (Pisum sativum L.) for growing pigs. In Exp. 1, 96 pigs (initial BW = 22 +/- 3.35 kg) were allotted to four treatment groups (four pigs per pen, six replicate pens per treatment) and fed growing (0.95% Lys) and finishing (0.68% Lys) diets containing 0, 12, 24, or 36% field peas (as-fed basis). There were no differences among the treatment groups in ADG, ADFI, or G:F. Likewise, there were no differences in backfat thickness or lean meat percent among treatment groups, but pigs fed diets containing 12, 24, or 36% field peas had greater (P < 0.05) loin depths than pigs fed the control diet. In Exp. 2, 120 pigs (initial BW = 7.8 +/- 1.04 kg) were allotted to four treatment groups 2 wk after weaning. Pigs were then fed diets containing 0, 6, 12, or 18% field peas (as-fed basis) during the following 4 wk. There were five pigs per pen and six replicate pens per treatment. Results of the experiment showed no differences in ADG, ADFI, or G:F among treatment groups. In Exp. 3, apparent (AID) and standardized (SID) ileal digestibility coefficients of CP and AA in field peas and soybean meal were measured using six individually penned growing pigs (initial BW = 36.5 +/- 2.1 kg) arranged in a repeated 3 x 3 Latin square design. The AID for Met, Trp, Cys, and Ser, and the SID for Met, Trp, and Cys were lower (P < 0.05) in field peas than in soybean meal; but for CP and all other AA, no differences in AID or SID were observed between the two feed ingredients. Experiment 4 was an energy balance experiment conducted to measure the DE and ME concentrations in field peas and corn. Six growing pigs (initial BW = 85.5 +/- 6.5 kg) were placed in metabolism cages and fed diets based on field peas or corn and arranged in a two-period switch-back design. The DE values for field peas and corn (3,864 and 3,879 kcal/kg DM, respectively) were similar, but the ME of corn was higher (P < 0.05) than the ME of field peas (3,825 vs. 3,741 kcal ME/kg DM). The results from the current experiments demonstrate that the nutrients in South Dakota-grown field peas are highly digestible by growing pigs. Therefore, such field peas may be included in diets for nursery pigs and growing-finishing pigs in amounts of at least 18 and 36%, respectively, without negatively affecting pig performance.     

Net energy of oat bran,wheat bran,and palm kernel expellers fed to growing pigs using indirect calorimetry

The objectives of this experiment were to (a) determine the effects of fiber increase in diets on heat production (HP), (b) determine the net energy (NE) of oat bran (OB), wheat bran (WB), and palm kernel expellers (PKE) fed to growing pigs using indirect calorimetry (IC). Twenty‐four growing barrows (29.2 ± 2.6 kg) were randomly allotted to one of four diets with six replicate pigs per diet. Diets included a corn‐soybean meal basal diet and three test diets containing 30% OB, WB or PKE, respectively. During each period, pigs were individually housed in metabolism crates for 20 days, including 14 days to adapt to the diets. On day (d) 15, pigs were transferred to the open‐circuit respiration chambers for determination of daily total HP and were fed one of the four diets at 2.3MJ ME/kg body weight (BW)^0.6/day. Total feces and urine were collected for the determination of digestible energy (DE) and metabolizable energy (ME) and daily total HP was measured from d 15 to d 19 and fasted on day 20 for the measurement of fasting heat production (FHP). The apparent total tract digestibility (ATTD) of dry matter (DM), gross energy (GE), and organic matter (OM) were greater (p < 0.01) in pigs fed the basal diet compared with those fed the test diets. The ATTD of neutral detergent fiber (NDF) was lower (p < 0.01) in pigs fed the WB diet compared with those fed the basal, OB, or PKE diets. The ATTD of ether extract (EE) in pigs fed the PKE diet was greater (p < 0.01) compared with those fed the other diets. The average total HP and FHP in pigs fed the four diets were 1261 and 787 kJ/kg BW^0.6/d, respectively, and were not significantly affected by diet characteristics. The NE:ME ratio for diets ranged from 78.1 to 80.9%. The NE contents of OB, WB, and PKE were 10.93, 7.47, and 8.71 MJ/kg DM, respectively.     

Amino acid digestibility and energy content of deoiled (solvent-extracted) corn distillers dried grains with solubles for swine and effects on growth performance and carcass characteristics

A study with 3 experiments was conducted to determine the AA digestibility and energy concentration of deoiled (solvent-extracted) corn distillers dried grains with solubles (dDGS) and to evaluate its effect on nursery pig growth performance, finishing pig growth performance, and carcass traits. In Exp. 1, a total of 5 growing barrows (initial BW = 30.8 kg) were fitted with a T-cannula in the distal ileum and allotted to 1 of 2 treatments: 1) a diet with dDGS as the sole protein source, or 2) a N-free diet for determining basal endogenous AA losses in a crossover design at 68.0 kg of BW. Apparent and standardized (SID) ileal digestibility of AA and energy concentration of dDGS were determined. In Exp. 2, a total of 210 pigs (initial BW = 9.9 kg) were used in a 28-d experiment to evaluate the effect of dDGS on nursery pig performance. Pigs were allotted to 5 dietary treatments (0, 5, 10, 20, or 30% dDGS) formulated to contain equal ME (increased added fat with increasing dDGS) and SID Lys concentrations based on the values obtained from Exp. 1. In Exp. 3, a total of 1,215 pigs (initial BW = 29.6 kg) were used in a 99-d experiment to determine the effect of dDGS on growth and carcass characteristics of finishing pigs. Pigs were allotted to dietary treatments similar to those used in Exp. 2 and were fed in 4 phases. The analyzed chemical composition of dDGS in Exp. 1 was 35.6% CP, 5.29% ash, 4.6% fat, 18.4% ADF, and 39.5% NDF on a DM basis. Apparent ileal digestibility values of Lys, Met, and Thr in dDGS were 47.2, 79.4, and 64.1%, respectively, and SID values were 50.4, 80.4, and 68.9%, respectively. The determined GE and DE and the calculated ME and NE values of dDGS were 5,098, 3,100, 2,858, and 2,045 kcal/kg of DM, respectively. In Exp. 2, nursery pig ADG, ADFI, and G:F were similar among treatments. In Exp. 3, increasing dDGS reduced (linear; P < 0.01) ADG and ADFI but tended to improve (linear; P = 0.07) G:F. Carcass weight and yield were reduced (linear; P < 0.01), loin depth tended to decrease (linear; P = 0.09), and carcass fat iodine values increased (linear; P < 0.01) as dDGS increased. No difference was observed in backfat, percentage of lean, or fat-free lean index among treatments. In conclusion, dDGS had greater CP and AA but less energy content than traditional distillers dried grains with solubles. In addition, when dietary fat was added to diets to offset the reduced ME content, feeding up to 30% dDGS did not affect the growth performance of nursery pigs but did negatively affect the ADG, ADFI, and carcass fat quality of finishing pigs.     

Cereal type and heat processing of the cereal affect nutrient digestibility and dynamics of serum insulin and ghrelin in weanling pigs

The effects of feeding corn or rice, either raw or heat processed (HP), on apparent total tract digestibility (ATTD) and apparent ileal digestibility (AID) of nutrients and on insulin and ghrelin concentrations in the serum were studied in young pigs. Pigs were weaned at approximately 23 ± 3 d of age and weighed 7.4 ± 1.2 kg. Each of the 4 treatments was replicated 9 times, and the experimental unit was a pig individually housed. Pigs (5 males and 4 females/treatment) were fed their respective diets ad libitum from 23 to 47 d of age. At 37 d of age, the effects of dietary treatments on the fasting and postprandial concentrations of insulin and total and acylated ghrelin were studied. The ATTD of OM, GE, and ether extract were, respectively, 4.3, 5.4, and 3.6% greater (P < 0.05) for the rice than for the corn diets, but CP digestibility was not affected. Similar results were observed for AID. Heat processing of the cereal increased (P < 0.05) the ATTD by 2.1% for OM, 3.2% for GE, 7.1% for ether extract, and 2.2% for CP and tended to increase the AID of CP (P = 0.06) and starch (P = 0.09). The postprandial serum insulin response was greater and was more prolonged in pigs fed raw rice than in pigs fed raw corn (P < 0.05). In addition, the effects of HP on serum insulin response were more pronounced with corn than with rice (cereal × HP, P < 0.05). Total ghrelin concentration was not affected by treatment, but acylated ghrelin was greater (P < 0.05) at 6 h postprandially in pigs fed rice than in pigs fed raw corn. Feeding rice and HP corn increased nutrient digestibility and insulin response in the early postprandial period and increased the acylated ghrelin response in the late postprandial period compared with feeding raw corn.     

Effect of feeding acidified or fermented barley using Limosilactobacillus reuteri with or without supplemental phytase on diet nutrient digestibility in growing pigs

Fermentation of cereal grains may degrade myo-inositol 1,2,3,4,5,6-hexakis (dihydrogen phosphate) (InsP₆) thereby increasing nutrient digestibility. Effects of chemical acidification or fermentation with Limosilactobacillus (L.) reuteri with or without phytase of high β-glucan hull-less barley grain on apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of nutrients and gross energy (GE), standardized ileal digestibility (SID) of crude protein (CP) and amino acids (AAs), and standardized total tract digestibility (STTD) of P were assessed in growing pigs. Pigs were fed four mash barley-based diets balanced for water content: 1) unfermented barley (Control); 2) chemically acidified barley (ACD) with lactic acid and acidic acid (0.019 L/kg barley grain at a ratio of 4:1 [vol/vol]); 3) barley fermented with L. reuteri TMW 1.656 (Fermented without phytase); and 4) barley fermented with L. reuteri TMW 1.656 and phytase (Fermented with phytase; 500 FYT/kg barley grain). The acidification and fermentation treatments occurred for 24 h at 37 °C in a water bath. The four diets were fed to eight ileal-cannulated barrows (initial body weight [BW], 17.4 kg) for four 11-d periods in a double 4 × 4 Latin square. Barley grain InsP₆ content of Control, ACD, Fermented without phytase, or Fermented with phytase was 1.12%, 0.59%, 0.52% dry matter (DM), or not detectable, respectively. Diet ATTD of DM, CP, Ca, and GE, digestible energy (DE), predicted net energy (NE) value, and urinary excretion of P were greater (P < 0.05) for ACD than Control. Diet ATTD of DM, CP, Ca, GE, DE and predicted NE value, urinary excretion of P was greater (P < 0.05), and diet AID of Ca and ATTD and STTD of P tended to be greater (P < 0.10) for Fermented without phytase than Control. Diet ATTD of GE was lower (P < 0.05) and diet ATTD and STTD of P, AID and ATTD of Ca was greater (P < 0.05) for Fermented with phytase than Fermented without phytase. Acidification or fermentation with/without phytase did not affect diet SID of CP and AA. In conclusion, ACD or Fermented without phytase partially degraded InsP₆ in barley grain and increased diet ATTD of DM, CP, and GE, but not SID of CP and most AA in growing pigs. Fermentation with phytase entirely degraded InsP₆ in barley grain and maximized P and Ca digestibility, thereby reducing the need to provide inorganic dietary P to meet P requirements of growing pigs.     

Apparent ileal digestibility of amino acids and the digestible and metabolizable energy content of high-oil corn varieties and its effects on growth performance of pigs.

Two experiments were conducted to compare the nutritional value of normal and high-oil corn for pigs. The normal corn and the two varieties (high-oil corns A and B) of high-oil corn contained 4.41, 7.35 and 8.86% ether extract, on DM basis, respectively. In experiment 1, six non-littermate crossbred barrows (37.8 +/- 1.3 kg BW) were fitted with ileal T-cannulas and used in a double replicated Latin Square digestion trial. Three diets were formulated containing 96.6% of one of the three varieties of corn as the only protein source. Chromic oxide (0.4%) was added as a digestibility marker. Additional vitamins and minerals were added to meet requirements. The digestible energy concentrations for normal corn and high-oil corn A and B were 16.53, 16.99 and 17.07 MJ/kg while the metabolizable energy values were 15.82, 16.32 and 16.36 MJ/kg, on DM basis, respectively. The ileal amino acid digestibility of high-oil corn was generally higher than that of normal corn with significant differences being observed for the essential amino acids isoleucine and phenylalanine. In experiment 2, 96 pigs (8.01 +/- 0.14 kg BW) were used to evaluate four diets in a 2 x 2 factorial design conducted over a 35-day period. Corn variety (high-oil vs. normal corn) and nutrient density (high content of protein and ME vs. low content of protein and ME) were set as the two main effects. During the first 14 days, pigs fed high-oil corn diets consumed more feed and tended to get higher daily gain than pigs fed normal corn. Over the entire 35-day experiment, increasing dietary nutrient density increased daily gain and tended to increase feed conversion, while variety of corn had no significant effects on performance. Overall, the present results indicate that the energy concentration and ileal amino acid digestibility of high-oil corn varieties were equal or superior to those in normal corn and therefore they should be able to be effectively utilized in diets fed to swine.     

Effects of individual or combined xylanase and phytase supplementation on energy, amino acid, and phosphorus digestibility and growth performance of grower pigs fed wheat-based diets containing wheat millrun

The objective of these studies was to determine if dietary enzymes increase the digestibility of nutrients bound by nonstarch polysaccharides, such as arabinoxylans, or phytate in wheat millrun. Effects of millrun inclusion rates (20 or 40%), xylanase (0 or 4,375 units/kg of feed), and phytase (0 or 500 phytase units/kg of feed) on nutrient digestibility and growth performance were investigated in a 2 x 2 x 2 factorial arrangement with a wheat control diet (0% millrun). Diets were formulated to contain 3.34 Mcal of DE/kg and 3.0 g of true ileal digestible Lys/Mcal of DE and contained 0.4% chromic oxide. Each of 18 cannulated pigs (36.2 +/- 1.9 kg of BW) was fed 3 diets at 3x maintenance in successive 10-d periods for 6 observations per diet. Feces and ileal digesta were collected for 2 d. Ileal energy digestibility was reduced (P < 0.01) linearly by millrun and increased by xylanase (P < 0.01) and phytase (P < 0.05). Total tract energy digestibility was reduced linearly by millrun (P < 0.01) and increased by xylanase (P < 0.01). For 20% millrun, xylanase plus phytase improved DE content from 3.53 to 3.69 Mcal/kg of DM, a similar content to that of the wheat control diet (3.72 Mcal/kg of DM). Millrun linearly reduced (P < 0.01) ileal digestibility of Lys, Thr, Met, Ile, and Val. Xylanase improved (P < 0.05) ileal digestibility of Ile. Phytase improved ileal digestibility of Lys, Thr, Ile, and Val (P < 0.05). Millrun linearly reduced (P < 0.05) total tract P and Ca digestibility and retention. Phytase (P < 0.01) and xylanase (P < 0.05) improved total tract P digestibility, and phytase and xylanase tended to improve (P < 0.10) P retention. Phytase improved Ca digestibility (P < 0.05) and retention (P < 0.01). The 9 diets were also fed for 35 d to 8 individually housed pigs (36.2 +/- 3.4 kg of BW) per diet. Millrun reduced (P < 0.05) ADFI, ADG, and final BW. Xylanase increased (P < 0.05) G:F; phytase reduced (P < 0.05) ADFI; and xylanase tended to reduce (P = 0.07) ADFI. In summary, millrun reduced energy, AA, P, and Ca digestibility and growth performance compared with the wheat control diet. Xylanase and phytase improved energy, AA, and P digestibility, indicating that nonstarch polysaccharides and phytate limit nutrient digestibility in wheat byproducts. The improvement by xylanase of energy digestibility coincided with improved G:F but did not translate into improved ADG.     

Nutritional evaluation of high-digestible sorghum for pigs and broiler chicks

Two experiments were conducted to evaluate the nutritional quality of 2 varieties of Purdue high-digestible sorghum (PHD1 and PHD2) and a normal sorghum, compared with corn, in diets of pigs and broiler chicks. In Exp. 1, 12 pigs (average BW, 55 kg) fitted with ileal T-cannula were fed 4 diets containing 946 g of corn or sorghum (PHD1, PHD2, and normal) per kg in a 2-period crossover design (i.e., each pig received 2 diets over a 2-wk period with 6 pigs per dietary treatment) to determine apparent ileal or total tract digestibility of nutrients and energy. There was no difference in the ileal or total tract digestibility of DM, energy, P, Ca, or N among dietary treatments. In Exp. 2, a total of 192 broiler chicks were grouped by weight into 8 blocks of 4 cages each with 6 chicks per cage, and cages were assigned randomly to 1 of the 4 dietary treatments within each block. Chicks were fed corn-soybean meal (SBM) or sorghum-SBM diets for 21 d to determine apparent total tract retention and then switched to diets containing 935 g of the corresponding corn or 1 of the 3 sorghum varieties per kg for 7 d to determine apparent ileal digestibility and total tract retention. Apparent ileal digestibilities of DM and P, as well as energy, were not different in chicks fed diets containing 935 g of corn or 1 of the 3 sorghum varieties per kg. However, apparent total tract retention of DM, energy, and N in chicks fed corn was greater (P < 0.05) than those fed 1 of the 3 sorghum varieties. Although the apparent ME content of corn was greater than PHD1 and normal sorghum (P < 0.01), it was not different from PHD2 sorghum. There was no difference in apparent total tract retention of DM between chicks fed the corn-SBM and PHD-SBM diets, but it was greater (P < 0.05) in chicks fed the corn-SBM diet than those fed the normal sorghum-SBM diet. Apparent total tract retention of N in chicks fed the PHD1-SBM diet was lower (P < 0.05) than in those fed the corn-SBM diet but greater (P < 0.05) than in chicks fed the normal sorghum-SBM meal diet. No difference in the apparent ME content between the corn-SBM and PHD2-SBM diets was observed, but it was greater (P < 0.05) for the corn-SBM diet than the PHD1- or normal sorghum-SBM diet. Weight gain, feed intake, and feed efficiency were not different in chicks fed the corn-SBM or sorghum-SBM diets. Sorghum could serve as a substitute for corn in cereal grain-SBM diets for pigs and broiler chicks.     

Amino acid and energy digestibility of protein sources for growing pigs

Two experiments were conducted to determine the apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of AA and DE, and to estimate ME and NE of rice protein concentrate, salmon protein hydrolysate, whey protein concentrate, and spray-dried plasma protein. In Exp. 1, 6 barrows (initially 29.5 +/- 2.5 kg of BW) were fitted with ileal T-cannulas and fed each of 5 cornstarch-based diets in a balanced crossover design over 35 d. During a given week, there were either 1 or 2 replications of each treatment, resulting in 6 total replications over 5 wk. The 4 test diets (fed from d 0 to 28) were formulated to contain 12.5% CP by using analyzed nutrient compositions of rice protein concentrate, salmon protein hydrolysate, whey protein concentrate, or spray-dried plasma protein. The fifth (N-free) diet was fed from d 28 to 35 to estimate basal endogenous losses of CP and AA, which were used to calculate SID. Ileal digesta were collected and analyzed, and AID and SID values were calculated. Apparent ileal digestible Lys, Met, and Thr values were 80.0 +/- 3.3, 65.6 +/- 3.1, and 68.4 +/- 4.5% for rice protein concentrate; 85.6 +/- 4.8, 85.5 +/- 4.3, and 69.8 +/- 8.5% for salmon protein hydrolysate; 93.3 +/- 1.4, 89.9 +/- 5.8, and 83.6 +/- 5.3% for whey protein concentrate; and 92.8 +/- 0.9, 85.7 +/- 2.1, 86.5 +/- 2.3% for spray-dried plasma protein, respectively. In Exp. 2, 6 barrows (initially 37.6 +/- 1.7 kg of BW) were fed each of 5 corn-based diets in a balanced crossover design over 35 d. During a given week, there were either 1 or 2 replications of each treatment, resulting in 6 total replications over 5 wk. The 4 diets containing the test ingredients were formulated to contain approximately 20% CP by using their analyzed nutrient compositions. The fifth (corn control) diet containing 8.2% CP was also used to calculate energy values by difference. Feces were collected to determine DE. The ME and NE contents were estimated using published regression equations. The DE, ME, and NE (as-fed) values were 4,724 +/- 461, 4,226 +/- 437, and 3,235 +/- 380 kcal/kg for rice protein concentrate; 4,173 +/- 1,052, 3,523 +/- 1,002, and 2,623 +/- 872 kcal/kg for salmon protein hydrolysate; 4,949 +/- 1,002, 4,352 +/- 955, and 3,344 +/- 831 kcal/kg for whey protein concentrate; and 4,546 +/- 673, 3,979 +/- 652, and 3,020 +/- 567 kcal/kg for spray-dried plasma protein, respectively. The excellent AA digestibility and relatively high DE, ME, and NE values indicate that these protein sources warrant further investigation as ingredients for growing pig diets.     

Comparative digestibility of energy and nutrients in fibrous feed ingredients fed to Meishan and Yorkshire pigs

The objective of this experiment was to test the hypothesis that differences in the digestibility of total dietary fiber among breeds of pigs is influenced by the type of fiber fed and also by the age of the pig. Five Meishan pigs (BW: 77.2 ± 15.2 kg; 5 mo old), 5 light Yorkshire pigs (BW: 80.1 ± 11.2 kg; 4 mo old), and 5 heavy Yorkshire pigs (BW: 102.1 ± 3.5 kg, 5 mo old) were surgically prepared with a T-cannula in the distal ileum. A corn-soybean meal diet (control) was formulated with 5 g?kg(-1) of titanium dioxide as an indigestible marker. Three additional diets were formulated by replacing 30% of the control diet with 30% of distillers dried grains with solubles (DDGS), soybean hulls, or sugar beet pulp, and 1 diet was formulated by replacing 15% of the control diet with 15% pectin. Each group of pigs was allotted to a 5 × 5 Latin square design, and pigs were fed the 5 experimental diets during five 14-d periods. Fecal samples were collected on d 12, and ileal digesta were collected on d 13 and 14 of each period. The apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of GE and nutrients in each ingredient were calculated using the substitution method. Hindgut disappearance was calculated as the difference between ATTD and AID. When fed the control diet, Meishan pigs tended (P < 0.10) to have a greater AID of GE and CP (78.6 and 80.3%, respectively) than light (77.0 and 78.9%, respectively) and heavy (75.7 and 76.9%, respectively) Yorkshire pigs, and they had a greater (P < 0.05) ATTD of DM, GE, and carbohydrates (89.2, 89.5, and 95.5%, respectively) than light (86.6, 86.4, and 92.4%, respectively) and heavy (87.0, 86.6, and 93.0%, respectively) Yorkshire pigs. The ATTD of DM, GE, CP, carbohydrates, and total dietary fiber in DDGS (75.4, 76.3, 81.3, 78.0, and 75.3%, respectively) was greater (P < 0.01) in Meishan pigs than in light (55.7, 58.5, 66.7, 49.2, and 39.0%, respectively) and heavy (59.8, 62.9, 70.0, 51.1, and 55.7%, respectively) Yorkshire pigs. There were no differences among the 3 groups of pigs in the ATTD of GE or nutrients in soybean hulls, sugar beet pulp, or pectin. The hindgut disappearance of DM and carbohydrates in DDGS by Meishan pigs (26.8 and 52.9%, respectively) was greater (P < 0.05) than in the light (10.0 and 22.8%, respectively) and Heavy Yorkshire pigs (12.2 and 20.0%, respectively), but for the other ingredients, no differences in hindgut disappearance among Meishan, light Yorkshire, and heavy Yorkshire pigs were observed. In conclusion, Meishan pigs have a greater ATTD of DM, GE, and some nutrients in corn-soybean meal diets and in DDGS than Yorkshire pigs.     

Nutrient digestibility of extruded canola meal in ileal-cannulated growing pigs and effects of its feeding on diet nutrient digestibility and growth performance in weaned pigs

Canola meal (CM) contains less crude protein (CP) and more fiber and anti-nutritional factors such as glucosinolates than soybean meal (SBM) and consequently has a lower nutrient digestibility. Therefore, processing strategies that may increase the feeding value of CM warrant study. In two experiments, the effects of extrusion of Brassica napus CM on apparent (AID) and standardized ileal digestibility (SID) of amino acids (AA), apparent total tract digestibility (ATTD) of gross energy (GE) in growing pigs, and growth performance and diet digestibility in weaned pigs were assessed. Solvent-extracted CM was extruded using a single-screw extruder at three screw speeds: 250 (CM-250), 350 (CM-350), or 450 (CM-450) rpm. In exp. 1, in a double 4 × 4 Latin square, eight ileal-cannulated barrows (initial body weight [BW], 68.1 kg) were fed corn starch-based diets containing 50% CM or extruded CM. The CM sample contained 43.2% CP, 33.2% total dietary fiber (TDF), and 8.9 µmol of total glucosinolates/g on a dry matter (DM) basis. Extrusion increased (P < 0.05) the AID of CP, reduced (P < 0.05) apparent hindgut fermentation of CP, and decreased (P < 0.05) predicted net energy (NE) value of diets. Extrusion increased diet AID and CM SID of most indispensable AA by 3.1 to 5.3%-units. In exp. 2, 200 weaned pigs (initial BW, 8.3 kg) were fed diets containing 20% SBM, CM, or extruded CM starting 2 wk postweaning for 3 wk. The CM sample contained 42.7% CP, 28.3% TDF, and 5.3 µmol total glucosinolates/g DM. Wheat-based diets provided 2.3 Mcal NE/kg and 5.1 g SID Lys/Mcal NE. Dietary inclusion of extruded CM replacing SBM decreased (P < 0.05) diet ATTD of DM, GE and CP, and DE value. Average daily feed intake, average daily gain (ADG), and gain:feed (G:F) of pigs did not differ between extruded CM and SBM diets and were not affected by extrusion, but increasing extruder screw speed linearly increased (P < 0.05) ADG for day 1 to 7 and G:F for the entire trial. In conclusion, extrusion increased diet AID and CM SID of AA but not DE and predicted NE values of CM. However, increasing extruder speed did not further increase the SID of most of the AA of CM in growing pigs. Dietary inclusion of 20% CM or extruded CM did not affect the growth performance in weaned pigs.     

Nutritional value for swine of extruded corn and corn fractions obtained after dry milling

The experiment was designed to assess whether corn fractions or extrusion of corn can result in feed ingredients with a greater nutritional value than corn. Corn grain (8.0% CP, 0.21% P, 9.8% NDF) was processed by extrusion (82.8 degrees C, 345 kPa steam pressure for 12 s) or by dry milling to derive fractions rich in germ (13.1% CP, 1.19% P, 17.2% NDF), hulls (8.1% CP, 0.27% P, 32.6% NDF), and endosperm, namely tails (6.6% CP, 0.07% P, 3.6% NDF) and throughs (7.4% CP, 0.15% P, 4.5% NDF). Relative recovery in each fraction was 16, 20, 44, and 20%, respectively. Ileal digestibility of DM, P, and amino acids was determined using diets containing 7.0% CP from soybean meal and 5.3% CP from one of the test products. To allow for determination of standardized ingredient, ileal digestibility, basal endogenous AA losses were determined using a protein-free diet (74.6% cornstarch and 18.7% sucrose). Soybean meal ileal digestibility was determined using a diet (12.3% CP) based on soybean meal (23.3%). Eight barrows (27 +/- 2 kg) fitted with T-cannulas were fed 8 experimental diets (5-d adaptation and 2-d collection period) such that each diet was evaluated in at least 5 barrows. Relative to corn (77.9 +/- 1.2%), ileal digestibility of DM was greater for extruded corn (82.5%; P = 0.02), tails (85.9%; P < 0.01), and throughs (85.0%; P < 0.01), but it was lower for hulls (62.2%; P < 0.01) and germ (51.1%; P < 0.01). For P, corn (41.6 +/- 9.5%), throughs (47.2%), and hulls (57.3%) had similar ileal digestibility, but germ (7.9%) had lower ileal digestibility (P = 0.02) than corn; tails (27.6%) and extruded corn (23.5%) were not different from corn or germ but were lower than throughs and hulls. For total AA, corn (84.7 +/- 2.4%), throughs (84.3%), and hulls (85.8%) had similar ileal digestibility, but germ (76.6%) had lower ileal digestibility (P < 0.01) than corn; tails (82.0%) and extruded corn (81.7%) were intermediate. In conclusion, germ and hulls have a low ileal DM digestibility; germ also has low AA and P digestibility. Extrusion improved the ileal DM digestibility of corn. To maximize the ileal digestibility, removal of germ and hull from corn or extrusion of corn may thus be of interest.