Swine Day, 2013
Permanent URI for this collectionhttps://hdl.handle.net/2097/17298
Browse
Recent Submissions
Item Open Access Effects of low-, medium-, and high-oil dried distillers grains with solubles on growth performance, nutrient digestibility, and fat quality in finishing pigs(Kansas State University. Agricultural Experiment Station and Cooperative Extension Service, 2014-05-09) Graham, A. B.; Goodband, Robert D.; Tokach, Michael D.; Dritz, Steven S.; DeRouchey, Joel M.; Nitikanchana, Sureemas; Updike, J. J.; goodband; mtokach; dritz; jderouchA total of 1,480 pigs were used in 3 experiments to determine the effects of dried distillers grains with solubles (DDGS) varying in oil content on growth performance, carcass characteristics, carcass fat quality, and nutrient digestibility in growing-finishing pigs. In Exp. 1, 1,198 pigs (PIC 337 × 1050, initially 101.6 lb) were used to evaluate the effects of corn DDGS with 5.4 or 9.6% oil (as-fed). Pigs were allotted to a cornsoybean meal–based control diet or diets with 20 or 40% of the two DDGS sources. From d 0 to 82, ADG was unaffected by DDGS source or level. Increasing 5.4% oil DDGS made F/G poorer (linear, P < 0.01), whereas F/G did not change for pigs fed 9.6% oil DDGS. Regardless of DDGS source, carcass yield and HCW decreased (linear, P < 0.04) with increasing DDGS. Increasing DDGS increased jowl iodine value (IV), but the magnitude was greater in pigs fed the 9.6% oil DDGS compared with those fed 5.4% oil DDGS (DDGS source × level interaction; P < 0.01). In Exp. 2, a total of 270 pigs (PIC 327 × 1050, initially 102.5 lb) were allotted a corn-soybean meal–based control diet with 20 or 40% of a 9.4% oil or 12.1% oil DDGS. From d 0 to 75, ADG increased for pigs fed increasing 9.4% oil DDGS but not for pigs fed 12.1% oil DDGS (quadratic interaction, P < 0.02). Increasing DDGS increased (linear, P < 0.01) jowl IV and tended (linear, P < 0.07) to improve F/G. Regardless of source, HCW and carcass yield decreased (linear, P < 0.05) as DDGS increased. In Exp. 3, nutrient digestibility of the 4 DDGS sources was determined using pigs fed either a corn-based basal diet or a DDGS diet with 50% basal diet and 50% DDGS. On an as-fed basis, corn contained 1,756 and 1,594 kcal/lb GE and DE, respectively. The 5.4, 9.6, 9.4, and 12.1% oil DDGS contained 1,972, 2,108, 2,142, and 2,224 kcal/lb (as-fed) GE and 1,550, 1,674, 1,741, and 1,694 kcal/lb DE, respectively (as-fed). Stepwise regression indicated that the oil (ether extract) content was the only significant variable in explaining differences in energy content, and that a 1% change in oil content will change the DE by 28 kcal/lb (Adjusted R2 = 0.41) and NE by 52 kcal/lb (Adjusted R2 = 0.86; as-fed).Item Open Access Effects of withdrawing high-fiber ingredients prior to market on growth performance, carcass characteristics, and economics in commercial finishing pigs(Kansas State University. Agricultural Experiment Station and Cooperative Extension Service, 2014-05-09) Coble, Kyle F.; DeRouchey, Joel M.; Dritz, Steven S.; Tokach, Michael D.; Goodband, Robert D.; jderouch; dritz; mtokach; goodbandA total of 1,089 mixed-sex pigs (PIC 337 × 1050; initial BW 98.2 lb) were used in a 96-d study. The two diet types fed during the study were a corn-soybean meal control diet with low NDF (9.3%) and a high-fiber diet with high NDF (19%) that contained 30% dried distillers grains with solubles (DDGS) and 19% wheat middlings (midds). Pens of pigs were randomly allotted to 1 of 6 dietary feeding strategies with 25 to 27 pigs per pen and 7 replications per treatment. The six dietary strategies consisted of the corn-soybean meal control diet or high-fiber diet fed for the duration of the study, or the high-fiber diet fed until 24, 19, 14, or 9 d prior to harvest, at which time the pigs were switched to the corn-soybean meal control diet for the remainder of the study. Overall (d 0 to 96), pigs fed the high-fiber diet through the entire study compared with the corn-soy control diet had lower (P < 0.01) ADG and poorer F/G. This reduction in growth performance led to a trend for poorer (P < 0.10) caloric efficiency and lower (P < 0.01) final BW in pigs fed the high-fiber diet throughout compared to the control. For pigs fed the high-fiber diet then switched to the corn-soy control, ADG and ADFI were not different between withdrawal days, but F/G tended (linear; P < 0.07) to improve as withdrawal days increased from 0 to 24 d. Pigs fed the high-fiber diet throughout had a 9.5-lb lighter (P < 0.01) HCW compared to those fed the corn-soy control. Neither percentage yield using the farm live weight or plant live weight were significantly influenced by withdrawal days from the high-fiber diet; however, HCW increased linearly (P < 0.05) as withdrawal days increased. Backfat and loin depth both decreased (P < 0.02) in pigs fed the high-fiber diet throughout compared with those fed the corn–soybean meal diet. Loin depth increased, then decreased (quadratic; P < 0.04) as high-fiber diet withdrawal time increased. Total feed cost per pig and feed cost per lb of gain was lower (P < 0.01) for pigs fed the high-fiber diet until harvest, but carcass gain value per pig also decreased (P < 0.01) by $7.34. Total feed cost tended (P < 0.10) to increase and carcass gain value increased (P < 0.05) as high-fiber diet withdrawal time increased. Although no significant differences were observed in income over feed cost (IOFC) between treatments, switching pigs from the high-fiber diet to the corn-soybean meal diet at 14 to 19 d before market numerically increased IOFC by $1.42 to $2.30/pig over pigs fed the high-fiber diet continuously and $2.04 to 2.92/pig over pigs fed the corn-soybean meal diet throughout. These data indicate that much of the benefit in lower feed cost from feeding high-fiber diets can be captured while minimizing the reduction in revenue by switching pigs to a low-fiber, high-energy diet for 14 to 19 d prior to market.Item Open Access Ammonia and hydrogen sulfide emissions from swine production facilities in North America: a meta-analysis(Kansas State University. Agricultural Experiment Station and Cooperative Extension Service, 2014-05-09) Liu, Zifei; Powers, W. J.Ammonia (NH3) and hydrogen sulfide (H2S) emissions from swine production facilities receive considerable attention due to human health and environmental implications. Accurate quantification of farm emissions is essential to ensure compliance with regulatory requirements. The objectives of this study were to provide a review of the literature on NH3 and H2S emissions from swine production facilities in North America with a meta-analysis that integrates results of independent studies, including measured emissions data from both swine houses and manure storage facilities as well as concentration data in the vicinity of swine production facilities. Results from more than 80 studies were identified through a thorough literature search, and the data were compiled together with results from the 11 swine sites in the National Air Emissions Monitoring Study (NAEMS). Data across studies were analyzed statistically using the MIXED procedures of SAS. Median emissions rates from swine houses were 2.78 and 0.09 kg/year per pig for NH3 and H2S, respectively. Median emissions rates from swine storage facilities were 2.08 and 0.20 kg/year per pig for NH3 and H2S, respectively. The Emergency Planning and Community Right-to-Know Act (EPCRA) require reporting of NH3 and H2S emissions that exceed 100 lb/d. The size that may trigger the need for a farm to report NH3 emissions is 3,410 pigs based on median NH3 emissions rates in the literature, but the threshold can be as low as 992 pigs based on 90th-percentile emissions rates. Swine hoop houses had significantly higher NH3 emission rates than other manure-handling systems (P < 0.01), whereas deep pit houses had the highest H2S emission rates (P = 0.03). Farrowing houses had the highest H2S emission rates, followed by gestation houses, and finishing houses had lowest H2S emission rates (P < 0.01). Regression models for NH3 and H2S emission rates were developed for finishing houses with deep pits, recharge pits, and lagoons. The NH3 emission rates increased with increasing air temperature, but effects of air temperature on H2S emission rates were not significant. The recharge interval of manure pits significantly affected H2S but not NH3 emission rates. The H2S emission rates were also influenced by the size of the operation. Although NH3 and H2S concentrations at the edge of swine houses or lagoons were often higher than corresponding acute or intermediate minimum risk levels (MRLs), they decreased quickly to be less than corresponding chronic or intermediate MRLs as distances from emission sources increase. At distances 30 to 1,185 m from emission sources, the average ambient concentrations for NH3 and H2S were 66 ± 66 ppb and 3.1 ± 6.2 ppb, respectively.Item Open Access Amino acid digestibility and energy concentration of fermented soybean meal and camelina meal for swine(Kansas State University. Agricultural Experiment Station and Cooperative Extension Service, 2014-05-09) Graham, A. B.; DeRouchey, Joel M.; Goodband, Robert D.; Tokach, Michael D.; Dritz, Steven S.; Thaler, R. C.; jderouch; goodband; mtokach; dritzTwo experiments were conducted to determine the amino acid and GE digestibility of fermented soybean meal and camelina meal. For Exp. 1, to determine standardized ileal amino acid digestibility, five growing gilts (BW= 60.4 lb) were surgically fitted with T-cannulas at the terminal ileum and randomly allotted to 1 of 3 dietary treatments in a crossover design with 3 periods. The basal diets were corn starch–based with adequate vitamins and minerals to meet the pigs’ requirements. The experimental treatments consisted of the basal diet with 30% fermented soybean meal or 39.25% camelina meal as the sole protein sources. A third nitrogen-free diet was also fed to determine basal endogenous amino acid losses. For Exp. 2, to determine energy concentrations, 6 growing barrows (BW = 64.8 lb) were randomly allotted to 1 of 3 dietary treatments in a crossover design with 3 periods. The corn-based treatment diets had 25% fermented soybean meal or 30% camelina meal. A third corn basal diet was also offered to allow for energy calculations by the difference method. All diets contained 0.25% titanium oxide as an indigestible marker. Digesta samples were collected and analyzed for amino acid concentrations, and fecal samples were collected and analyzed for energy concentrations. After chemical analysis, standardized and apparent ileal digestible (SID and AID, respectively) amino acids were determined, and DE, ME, and NE were calculated for each ingredient. On a DM basis, GE, DE, ME, and NE were 1,973, 1,377, 1,232, and 880 kcal/lb, respectively, for fermented soybean meal and 2,075, 1,150, 1,041, and 715 kcal/lb, respectively, for camelina meal. In fermented soybean meal, the AID for lysine, methionine, threonine, and tryptophan were 63.5 ± 7.5, 84.6 ± 1.0, 74.0 ± 3.5, and 81.8 ± 1.4%, respectively, and SID values were 71.1 ± 6.2, 89.2 ± 2.1, 88.0 ± 3.1, and 93.7 ± 2.0%, respectively. For camelina meal, the AID for lysine, methionine, threonine, and tryptophan were 47.3 ± 7.7, 74.6 ± 3.3, 39.7 ± 6.8, and 67.3 ± 8.3%, respectively, and SID values were 53.9 ± 6.4, 77.7 ± 3.5, 51.6 ± 6.7, and 79.7 ± 6.8%, respectively. The SID availability for amino acids in fermented soybean meal were relatively high and similar to published values for soybean meal, with the exception of lysine. Standardized ileal digestible amino acid availability values for camelina meal were low, indicating that it may have contained the high glucosinolate concentrations generally observed in camelina meal.Item Open Access Regression analysis to predict growth performance from dietary net energy in growing-finishing pigs(Kansas State University. Agricultural Experiment Station and Cooperative Extension Service, 2014-05-09) Nitikanchana, Sureemas; Dritz, Steven S.; Tokach, Michael D.; DeRouchey, Joel M.; Goodband, Robert D.; White, Bradley J.; Nelssen, Jim L.; dritz; mtokach; jderouch; goodband; whiteb; jnelssenEnergy concentration in livestock feed is often altered to optimize pig growth performance and feed cost; therefore, an accurate prediction of growth performance as affected by feeding different energy levels is crucial. Data from 41 trials from 17 journal articles, 10 technical memos, and a thesis were used to develop a regression equation to predict ADG or gain to feed (G:F) as influenced by BW and NE content. Linear and quadratic terms of NE, average BW, CP, standardized ileal digestible [SID] lysine, crude fiber, NDF, ADF, fat, and ash, including their interaction terms, were the variables in the regression analysis. Our regression analysis showed that improvements in growth rate and feed efficiency could be obtained by increasing dietary NE across a wide variety of trials with different dietary ingredients and under different environmental conditions, but the magnitude of improvement in growth performances by dietary NE can be minimized if the amino acids are limiting. Regression equations from this paper can be used to predict the influence of dietary NE on ADG and G:F; however, these equations still need validation from growth studies not included in their development.Item Open Access Effects of added zinc and copper on growth performance and carcass characteristics of finishing pigs fed ractopamine HCl(Kansas State University. Agricultural Experiment Station and Cooperative Extension Service, 2014-04-30) Coble, Kyle F.; Paulk, Chad B.; DeRouchey, Joel M.; Tokach, Michael D.; Goodband, Robert D.; Dritz, Steven S.; jderouch; mtokach; goodband; dritzA total of 253 finishing pigs (PIC 327 × 1050; initial BW 204 lb) were used in a 28-d study to determine the effects of added Zn (Availa-Zn; Zinpro Corp., Eden Prairie, MN), Cu (Availa-Cu; Zinpro Corp.), or both to diets containing ractopamine HCl (RAC; Paylean; Elanco Animal Health, Greenfield, IN) on growth performance and carcass characteristics. Pens of pigs were randomly assigned to 1 of 5 treatments and balanced on average pig weight with 7 to 8 pigs per pen. Treatments included a control diet without RAC (negative control) and 4 diets containing 9 g/ton RAC with or without added Zn (50 ppm) or Cu (125 ppm) in a 2 × 2 factorial. Overall, pigs fed RAC had increased (P < 0.01) ADG and improved F/G, which resulted in approximately a 15.5-lb heavier (P < 0.01) pig compared with those fed the negative control diet. Pigs fed added Zn had decreased (P < 0.05) ADG and tended to have decreased (P < 0.09) ADFI. Pigs fed added Cu also tended (P < 0.10) to have decreased ADG. No differences were observed in F/G when Zn or Cu was added to the diet. Hot carcass weight, carcass yield, loin depth, and percentage lean increased (P < 0.01) in pigs fed the positive control diet containing RAC compared with those fed the negative control diet, whereas backfat was unaffected. Carcass characteristics were not affected by added Zn or Cu. Feed cost and revenue increased (P < 0.01) for pigs fed the positive control diet containing RAC by approximately $9.63 and $10.08, respectively, compared with pigs fed the negative control diet; however, no difference was observed in feed cost per lb of gain. Income over feed cost (IOFC) did not differ in pigs fed the negative or positive control diet. Adding Zn decreased (P < 0.05) revenue per pig, and adding Cu tended to increase (P < 0.06) feed cost per lb of gain and reduce (P < 0.10) revenue per pig. There were no differences in IOFC between diets containing added Zn and no added Zn. Added Cu reduced (P < 0.05) IOFC. In summary, growth and carcass characteristics improved in pigs fed dietary RAC as expected, but adding Zn, Cu, or both to diets containing RAC did not improve growth performance, carcass characteristics, or IOFC. Adding copper actually reduced IOFC due to the added expense.Item Open Access Effects of dietary zinc level and ractopamine HCl on pork chop tenderness and shelf-life characteristics(Kansas State University. Agricultural Experiment Station and Cooperative Extension Service, 2014-04-30) Paulk, Chad B.; Tokach, Michael D.; Nelssen, Jim L.; Burnett, Derris D.; Vaughn, Mathew A.; Phelps, Kelsey J.; Dritz, Steven S.; DeRouchey, Joel M.; Goodband, Robert D.; Houser, Terry A.; Haydon, K. D.; Gonzalez, John M.; mtokach; jnelssen; dritz; jderouch; goodband; houser; johngonzA total of 320 finishing pigs (PIC 327 × 1050; initially 216 lb) were utilized to determine the effects of adding Zn to diets containing ractopamine HCl (RAC) on muscle fiber type distribution, fresh chop color, and cooked meat characteristics. Dietary treatments were fed for approximately 35 d and consisted of: a corn-soybean meal–based negative control (CON); a positive control diet with 10 ppm of RAC (RAC+); and the RAC+ diet plus 75, 150, or 225 ppm added Zn from either ZnO or Availa-Zn. Loins from 80 barrow and 80 gilt carcasses were evaluated. No Zn source effect or Zn source × level interactions we observed during the study (P > 0.10). Pigs fed the RAC+ had increased (P < 0.02) percentage type IIX and a tendency for increased percentage type IIB muscle fibers. Increasing added Zn decreased (linear, P = 0.01) percentage type IIA and tended to increase (P = 0.09) IIX muscle fibers. On d 1, 2, 3, 4, and 5 of display, pork chops from pigs fed the RAC+ treatment had greater (P < 0.03) L* values (lighter) compared with the CON. On d 0 and 3 of display, increasing added Zn tended to decrease (quadratic, P = 0.10) L* values and decreased (quadratic, P < 0.03) L* values on d 1, 2, 4, and 5. Pigs fed RAC+ had decreased (P < 0.05) a* values (less red) on d 1 and 4 of display and tended to have decreased (P < 0.10) a* values on d 0 and 2 compared with CON pork chops. RAC+ decreased (P < 0.001) metmyoglobin reducing ability (MRA) of pork chops on d 5. Chops from pigs fed added Zn had increased (quadratic, P < 0.03) MRA on d 3 and 5 of the display period. There was a trend for increased (linear, P = 0.07) cooking loss as added Zn increased in RAC diets. In conclusion, RAC+ diets produced chops that were lighter and less red but maintained a higher percentage of surface oxymyoglobin throughout a 5-d simulated retail display. RAC+ reduced MRA at the end of the display period, but supplementing Zn to RAC diets restored MRA to near CON treatment levels at the end of the display period.Item Open Access Effects of dietary byproduct feeding withdrawal prior to market on finishing pig growth performance, carcass characteristics, carcass fat quality, intestinal weights, and economics(Kansas State University. Agricultural Experiment Station and Cooperative Extension Service, 2014-04-30) Coble, Kyle F.; DeRouchey, Joel M.; Tokach, Michael D.; Goodband, Robert D.; Dritz, Steven S.; Houser, Terry A.; Goehring, Brandon L.; Azain, M. J.; jderouch; mtokach; goodband; dritz; houserA total of 288 pigs (PIC 327 × 1050; initially 84.7 lb) were used in an 88-d study to determine the timing of high-fiber ingredient removal from the diet prior to marketing to optimize growth performance, carcass characteristics (primarily yield), carcass fatty acid composition, and economics. Two diet types, a corn-soybean meal control diet with low NDF (9.3%) and a high-fiber, high-NDF (19%) diet that contained 30% dried distillers grains with solubles (DDGS) and 19% wheat middlings (midds) were used throughout the study. Pens of pigs were randomly allotted to 1 of 6 dietary feeding strategies with 8 pigs per pen (4 barrows and 4 gilts) and 6 replications per treatment. The 6 feeding strategies consisted of the corn-soy control diet or high-fiber diet fed for the duration of the study, or the high-fiber diet fed until 20, 15, 10, or 5 d prior to slaughter after which the pigs were switched to the corn-soybean meal control diet. Overall (d 0 to 88), ADG was not affected by diet type or withdrawal strategy. Pigs fed the high-fiber diet continuously tended (P < 0.07) to have increased ADFI compared with pigs fed the control diet. This led to an increase (P < 0.01) in F/G for pigs fed the high-fiber diet for the entire study compared to pigs fed the control diet. The caloric efficiency of live weight gain of pigs fed the high-fiber diet continuously was worse (P < 0.03) compared with pigs fed the control diet throughout. Withdrawing the highfiber diet and switching to the control diet did not influence growth performance. For carcass characteristics, percentage yield and backfat were reduced (P < 0.01), whereas loin depth and jowl iodine value (IV) increased (P < 0.01) in pigs fed the highfiber diet continuously compared with those fed the corn-soybean meal control diet. As days of withdrawal from the high-fiber diet increased, percentage yield improved (linear; P < 0.01), whereas jowl IV decreased (linear; P < 0.01) and backfat increased (quadratic; P < 0.04). These data suggest that 15- to 20-d of removal from high-fiber diets prior to slaughter was optimal in terms of percentage carcass yield. The full pluck from pigs fed the high-fiber diet continuously tended to weigh more (P < 0.10) than from those fed the control diet. In addition, pigs continuously fed the high-fiber diet had heavier (P < 0.01) whole intestines, specifically full large intestines, than pigs fed the control. For pigs fed the high-fiber diet then switched to the corn-soy control, whole intestine weight tended to decrease (linear; P < 0.06) and full large intestine weight decreased (linear; P < 0.02) as withdrawal time increased. In summary, pigs fed the high-fiber diet had increased F/G, poorer caloric efficiency, and lower carcass yield compared with pigs fed the corn-soy control. Withdrawing pigs from the high-fiber diet and switching them to a corn-soy control diet did restore carcass yield when done for the last 15 to 20 d prior to harvest.Item Open Access Influence of copper sulfate and tribasic copper chloride on feed intake preference in finishing pigs(Kansas State University. Agricultural Experiment Station and Cooperative Extension Service, 2014-04-30) Coble, Kyle F.; Card, Korrin N.; DeRouchey, Joel M.; Tokach, Michael D.; Woodworth, Jason C.; Goodband, Robert D.; Dritz, Steven S.; Usry, J.; jderouch; mtokach; jwoodworth; goodband; dritzA total of 150 pigs (PIC 327 × 1050; initially 191 lb BW) were used in a 15-d study to determine if pigs have a preference for diets that contain added Cu from either copper sulfate (CuSO4) or tribasic copper chloride (TBCC). Pens of pigs were randomly allotted to 1 of 3 dietary preference comparisons with 10 replications per comparison. Treatment diets used were a corn-soybean meal control with no supplemental Cu, or the control diet with 150 ppm of added Cu from either CuSO4 or TBCC. Pens contained two feeders, each with 1 of 2 treatment diets with feeders rotated once daily within each pen. The comparisons tested were: (1) control vs. CuSO4, (2) control vs. TBCC, and (3) CuSO4 vs. TBCC. For comparison 1, pigs consumed more (P < 0.01) of the control diet than the added CuSO4 diet (3.68 vs. 2.02 lb/d), which translated into pigs eating 66% of their daily intake from the control diet and 34% from the CuSO4 diet. For comparison 2, pigs consumed more (P < 0.03) of the control diet than the TBCC diet (3.30 vs. 2.49 lb/d), which equated to 57% of their daily intake from the control diet and 43% from the TBCC diet. For comparison 3, pigs consumed more (P < 0.01) of the diet containing TBBC than that with the added CuSO4 (3.50 vs. 1.96 lb/d), which was equivalent to 65% vs. 35% of daily intake, respectively. In summary, when given a choice, pigs preferred to consume a diet without high levels of added Cu; however, when given the choice between diets containing either Cu source, pigs preferred diets containing TBCC.Item Open Access Effects of copper source (Intellibond C or copper sulfate) on growth performance, carcass characteristics, pen cleanliness, and economics in finishing pigs(Kansas State University. Agricultural Experiment Station and Cooperative Extension Service, 2014-04-30) Coble, Kyle F.; Dritz, Steven S.; Usry, J.; Tokach, Michael D.; DeRouchey, Joel M.; Goodband, Robert D.; Nelssen, Jim L.; dritz; mtokach; jderouch; goodband; jnelssenA total of 1,143 pigs (PIC 337 × 1050, initially 55.3 lb) were used to determine the effects of tribasic copper chloride (TBCC; Intellibond C; Micronutrients Inc., Indianapolis, IN) or copper sulfate (CuSO4) on growth performance, carcass characteristics, pen cleanliness, and economics in a 111-d study. Pens of pigs were randomly allotted to 1 of 6 dietary treatments and balanced based on average pen weight in a completely randomized design with 25 to 28 pigs per pen and 8 pens per treatment. Treatment diets included a corn-soybean meal positive control, a high by-product diet with 30% dried distillers grains with solubles (DDGS) and 15% bakery meal (negative control), or the negative control diet with 75 or 150 ppm copper from CuSO4 or TBCC. All diets were formulated on a standardized ileal digestible (SID) amino acid basis and were 0.05% below the pig’s estimated lysine requirement throughout the trial. Pigs fed the corn-soybean meal positive control diet had improved (P < 0.01) F/G and tended to have increased ADFI (P < 0.08) compared with those fed the negative control, high by-product diet. Pigs fed increasing copper had improved (linear, P < 0.01) ADG and ADFI but tended to have slightly poorer (quadratic, P < 0.06) F/G. Although no interactions were observed between copper source and level, pigs fed increasing CuSO4 had increased (linear, P < 0.02) ADFI, whereas pigs fed increasing TBCC had increased ADG, ADFI, and final BW (linear, P < 0.01). Increasing added copper improved (linear, P < 0.02) HCW and loin depth, with the greatest response in HCW for pigs fed TBCC (linear, P < 0.01). For pen characteristics, pigs fed the high by-product diet had greater (P < 0.01) manure buildup and longer wash time than those fed the corn-soybean meal control diet. Addition of copper to diets did not influence pen wash time and had no impact on manure buildup. Economics were calculated on both a constant days on feed and constant market weight basis. Pigs fed either source of copper to a constant days on feed had an increase in feed cost per pig (linear, P < 0.01) as well as a higher (P < 0.10) revenue per pig. When economics were calculated on feeding pigs to a constant BW, facility costs decreased (linear, P < 0.05) with feeding copper. Although no significant differences were detected in income over feed and facility cost for added copper, the greatest numerical advantage to individual copper sources occurred at 75 PPM for CuSO4 ($0.26) and at 150 ppm for TBCC ($1.35 per pig). In summary, feeding increased levels of copper sulfate or TBCC in diets formulated slightly below the estimated SID lysine requirement increased growth rate and feed intake, resulting in increased final BW and HCW. Pigs fed TBCC at 150 ppm had the highest final BW (+12.8 lb) and HCW (+7.7 lb). In addition, the use of added copper in the diets did not increase time required to wash pens. More research is needed to determine whether the amino acid concentration influences the response to copper source and level in diets for growing and finishing pigs.Item Open Access Effects of added zinc in diets with ractopamine HCl on growth performance, carcass characteristics, and zinc concentrations in plasma, loin, and liver of finishing pigs(Kansas State University. Agricultural Experiment Station and Cooperative Extension Service, 2014-04-30) Paulk, Chad B.; Tokach, Michael D.; Nelssen, Jim L.; Dritz, Steven S.; Gonzalez, John M.; DeRouchey, Joel M.; Goodband, Robert D.; Hill, G. M.; Haydon, K. D.; mtokach; jnelssen; johngonz; dritz; jderouch; goodbandTwo experiments were conducted to determine the effects of added Zn from zinc oxide (ZnO) or Availa-Zn (AZ; Zinpro, Eden Prairie, MN) on growth performance and carcass characteristics of finishing pigs fed ractopamine HCl (RAC; Paylean; Elanco Animal Health, Greenfield, IN). In Exp. 1, a total of 320 pigs (PIC 327 × 1050, initially 215.9 lb) were used in a 35-d study. Pens of pigs were randomly allotted to 1 of 8 dietary treatments, with either 2 barrows or 2 gilts per pen and 20 pens per treatment. Dietary treatments included: a corn-soybean meal–based negative control (0.66% standardized ileal digestible [SID] lysine); a positive control diet (0.92% SID lysine) containing 10 ppm of RAC; and the RAC diet plus 75, 150, or 225 ppm added Zn from ZnO or AZ. The trace mineral premix provided a basal level of 55 ppm Zn from Zn Sulfate (ZnSO4) in all diets. In Exp. 1, overall (d 0 to 35), pigs fed RAC had improved (P < 0.04) ADG, F/G, d-35 BW, caloric efficiency on an ME and NE basis, HCW, carcass ADG and F/G, loin depth, percentage lean, and carcass caloric efficiency on an ME and NE basis, and reduced (P < 0.01) ADFI and backfat thickness compared with pigs fed the control diet. No evidence of a Zn effect or an interaction between Zn source and level was observed. Performance and IOFC did not differ in pigs fed diets with added Zn from either source. In Exp. 2, a total of 1,234 pigs (PIC 337 × 1050; initially 228.6 lb) were used in a 28-d study. Pens contained 23 to 28 pigs with either all barrow, all gilt, or mixed-sex allotments. Pens of pigs were blocked by BW, feeder type, and gender and were randomly assigned to diets. The 4 dietary treatments consisted of (1) a corn-soybean meal–based negative control diet (0.70% SID lysine); (2) a positive control diet (0.92% SID lysine) containing 10 ppm RAC; or the RAC diet plus 50 ppm added Zn from ZnO (3) or AZ (4). All diets contained 80 ppm Zn from ZnO provided by the trace mineral premix. On d 14, the 6 heaviest pigs from each pen (determined visually) were individually tattooed by pen and harvested to allow for carcass data collection, and on d 28, the remaining pigs were individually tattooed by pen and harvested to allow for carcass data collection. Overall (d 0 to 28), pigs fed RAC had improved (P < 0.001) ADG, F/G, final BW, and caloric efficiency on an ME and NE basis. Added Zn or Zn source did not affect (P > 0.20) growth performance. For pigs harvested on d 14, pigs fed RAC had improved (P < 0.001) carcass ADG, F/G, income over feed cost (IOFC), and carcass caloric efficiency on an ME and NE basis and a tendency for increased HCW, loin depth, and percentage lean compared with those fed the negative control diet. No differences were observed in carcass characteristics (P > 0.11) between pigs fed RAC diets and diets containing added Zn; however, pigs fed diets with added Zn from ZnO had increased (P < 0.05) carcass F/G, carcass yield, carcass IOFC, and carcass caloric efficiency on an ME and NE basis compared with those fed Zn from AZ. For pigs harvested on d 28, pigs fed RAC had improved (P < 0.01) HCW, carcass ADG and F/G, backfat thickness, loin depth, percentage lean, carcass IOFC, and carcass caloric efficiency on an ME and NE basis. No differences were observed in carcass characteristics between pigs fed RAC, and no additional Zn and diets containing added Zn from either source. Carcass characteristics did not differ in pigs fed diets with added Zn from ZnO vs. AZ. In conclusion, we observed improvements in growth and carcass performance from adding RAC similar to previous studies. In contrast with our previous research, these data indicate that adding Zn to finishing pig diets containing RAC did not improve overall performance. Consistent with the earlier research, income over feed cost (IOFC) was numerically increased with the addition of Zn.Item Open Access Effects of super-dosing phytase in diets with adequate phosphorus on finishing pig growth performance and carcass characteristics(Kansas State University. Agricultural Experiment Station and Cooperative Extension Service, 2014-04-30) Langbein, Kari Beth; Woodworth, Jason C.; Goodband, Robert D.; Tokach, Michael D.; Nelssen, Jim L.; Dritz, Steven S.; DeRouchey, Joel M.; jwoodworth; goodband; mtokach; jnelssen; dritz; jderouchA total of 274 finishing pigs (PIC 1050 × 327, initially 129 lb) were used in a 78-d study to compare the effects of adding high levels of three different sources of phytase (super-dosing) on growth performance and carcass characteristics of finishing pigs. Pigs were randomly allotted to pens with 7 or 8 pigs per pen and 9 replications per treatment. Dietary treatments included a corn-soybean meal–based control diet that was formulated to meet the available P requirements of the pigs without any added phytase, or three diets that were formed by adding 2,000 FTU/kg of phytase from 1 of 3 different phytase sources to the basal diet. The three phytase sources were Quantum Blue 5 G (AB Vista, Chesterfield, MO), Ronozyme HiPhos (GT) 2500 (DSM Nutritional Products, Parsippany, NJ), or Optiphos 1000 (Enzyvia, Sheraton, IN). Overall, regardless of source, super-dosing phytase had no effect (P > 0.26) on ADG, ADFI, or F/G; furthermore, there were no effects (P > 0.36) on any of the carcass criteria measured. In conclusion, in this environment with nutritionally adequate diets, this study suggests that super-dosing phytase had no beneficial effects on finishing pig growth or carcass performance.Item Open Access Effects of high levels of phytase (Ronozyme HiPhos) in low-lysine diets on the growth performance of nursery pigs(Kansas State University. Agricultural Experiment Station and Cooperative Extension Service, 2014-04-30) Langbein, Kari Beth; Goodband, Robert D.; Tokach, Michael D.; Dritz, Steven S.; DeRouchey, Joel M.; Bergstrom, J. R.; goodband; mtokach; dritz; jderouchTwo studies were conducted to determine the effects of added phytase in nursery pig diets formulated at or below their dietary lysine requirements. In Exp. 1, a total of 360 nursery pigs (PIC 327 × 1050, initially 27.3 lb) were used in an 18-d study with 5 pigs per pen and 18 pens per treatment in a university research facility. Pens of pigs were randomly allotted to 1 of 4 dietary treatments arranged in a 2 × 2 factorial with main effects of lysine level (adequate; 1.2% standardized ileal digestible [SID] lysine vs. marginal; 1.05% SID lysine) and phytase level (500 vs. 3,000 phytase units [FTU]/kg) with Ronozyme HiPhos (DSM Nutritional Products, Parsippany, NJ) as the source of phytase. Overall (d 0 to 18), no (P > 0.37) lysine × phytase interactions and no differences (P > 0.14) were observed among phytase levels. Pigs fed adequate lysine diets had greater (P < 0.01) ADG and BW and better F/G than those fed marginal lysine diets. In Exp. 2, 2,592 nursery pigs (PIC 1050 × 337, initially 23 lb) were fed 1 of 6 dietary treatments over 2 phases in a 36-d study in a commercial research barn. Dietary treatments included an adequate lysine (1.20 and 1.10% SID lysine in Phases 1 and 2, respectively) positive control diet containing 250 FTU/kg of phytase, or 5 low-lysine (1.10 and 1.00% SID lysine in Phases 1 and 2, respectively) diets with 250, 500, 1,000, 2,000, or 3,000 FTU/kg of phytase. Overall, pigs fed the positive control had greater (P < 0.02) ADG and better F/G than pigs fed the low-lysine diet with the same amount of phytase. Increasing phytase in the low-lysine diets increased (quadratic, P < 0.02) ADG, with the optimum response observed in pigs fed 1,000 FTU/kg. Phytase did not affect F/G. In summary, these studies confirmed the importance of feeding adequate lysine to optimize gain and feed efficiency. These studies also illustrate the differences between studies conducted in university vs. commercial settings because only the commercial study yielded a detectable phytase response. In the commercial study, pigs fed the low-lysine diet with 1,000 FTU/kg of phytase had performance similar to pigs fed high-lysine diets containing 250 FTU/kg of phytase.Item Open Access Effects of fine-grinding corn or dried distillers grains with solubles and diet form on growth performance and caloric efficiency of 25- to 50-lb nursery pigs(Kansas State University. Agricultural Experiment Station and Cooperative Extension Service, 2014-04-28) De Jong, Jon A.; DeRouchey, Joel M.; Tokach, Michael D.; Goodband, Robert D.; Dritz, Steven S.; jderouch; mtokach; goodband; dritzA total of 687 pigs (PIC 1050 barrows; initially 25.5 lb BW and 37 d of age) were used in a 21-d study to determine the effects of fine-grinding corn or dried distillers grains with solubles (DDGS) and diet form on nursery pig performance and caloric efficiency. Pens of pigs were balanced by initial BW and randomly allotted to 1 of 10 dietary treatments with 14 replications per treatment. There were 5 pigs per pen in two groups of nursery pigs. The 10 experimental diets included 4 corn-soybean meal–based diets consisting of: (1) corn ground to ~638 μ, in meal form; (2) treatment 1 in pellet form; (3) corn ground to ~325 μ, in meal form, and (4) treatment 3 in pellet form. The remaining 6 diets contained 30% DDGS. Diets 5 through 10 consisted of: (5) corn and DDGS ground to ~638 and 580 μ, in meal form; (6) diet 5 in pellet form; (7) corn and DDGS ground to ~638 and 391 μ, in meal form; (8) diet 7 in pellet form; (9) corn and DDGS ground to ~325 and 391 μ, in meal form; and (10) diet 9 in pellet form. Overall (d 0 to 21), a corn particle size (regardless of DDGS addition) × diet form interaction was observed (P < 0.01) as a result of increased ADFI when corn was finely ground and fed in pellet form but decreased intake when corn was finely ground and fed in meal form. Pelleting diets decreased (P < 0.001) ADG, ADFI, and final BW but improved (P < 0.001) F/G and caloric efficiency on both an ME and NE basis. Finegrinding corn decreased (P < 0.04) ADG as a result of numerically decreased ADFI (P < 0.16). Feeding 30% DDGS also decreased (P < 0.01) ADG, ADFI, and NE caloric efficiency and tended to decrease (P < 0.07) final BW. In conclusion, pelleting diets and fine-grinding ingredients reduced ADG as a result of decreased ADFI, but pelleting improved feed efficiency. Feeding 30% DDGS was detrimental to nursery pig growth performance.Item Open Access Effects of corn particle size and diet form on finishing pig growth performance and carcass characteristics(Kansas State University. Agricultural Experiment Station and Cooperative Extension Service, 2014-04-28) Nemechek, Jeremiah E.; Tokach, Michael D.; Coble, Kyle F.; DeRouchey, Joel M.; Goodband, Robert D.; Dritz, Steven S.; mtokach; jderouch; goodband; dritzA total of 960 pigs (PIC TR4 × Fast Genetics York-AND × PIC Line 02, initially 75.7 lb BW) were used in a 101-d trial to determine the effect of corn particle size and diet form on finishing pig growth performance and carcass characteristics. Pens were randomly allotted to 1 of 6 experimental treatments by initial BW with 8 pens per treatment and 20 pigs per pen. All diets were fed in four phases with the same cornsoybean meal–based diet containing 30% dried distillers grains with solubles (DDGS; Phases 1 to 3) or 15% DDGS (Phase 4) used for all diets. The 6 experimental treatments were arranged in a 2 × 3 factorial with main effects of final feed form (meal vs. pellet) and corn particle size (650 μ, 350 μ, or an equal blend of the 650 μ and 350 μ ground corn). Overall (d 0 to 101), linear particle size × diet form interactions were observed (P < 0.02) for ADFI and F/G due to ADFI decreasing and F/G improving as particle size was reduced for pigs fed meal diets but not for pigs fed pelleted diets. Pigs fed pelleted diets had increased (P < 0.001) ADG and final BW and improved (P < 0.001) F/G. As corn particle size decreased, ADG and ADFI decreased (P < 0.02) linearly. Pigs fed pelleted diets had increased (P < 0.001) HCW compared with pigs fed meal diets. Yield, backfat, and loin depth were not influenced by particle size or diet form. In summary, pigs fed pelleted diets had improved growth performance compared with those fed meal diets, with the greatest improvement in F/G observed from pigs fed coarse-ground (650 μ) corn. Feed efficiency improved as corn particle size decreased for pigs fed meal diets but not for those fed pelleted diets, suggesting that there was no benefit to grinding corn finer than 650 μ for pelleted diets.Item Open Access Effects of corn particle size, complete diet grinding, and diet form on 24- to 50-lb nursery pig growth performance(Kansas State University. Agricultural Experiment Station and Cooperative Extension Service, 2014-04-28) De Jong, Jon A.; DeRouchey, Joel M.; Tokach, Michael D.; Goodband, Robert D.; Hastad, C. W.; Dritz, Steven S.; jderouch; mtokach; goodband; dritzA total of 996 pigs (PIC TR4; initially 24.5 lb BW and 40 d of age) were used in a 21-d study to determine the effects of corn particle size, complete diet grinding, and diet form on nursery pig growth performance and caloric efficiency. Pens of pigs were balanced by initial BW and randomly allotted to 1 of 6 dietary treatments with 6 replications per treatment and 28 pigs per pen. The same corn-soybean meal–based diet containing 30% corn dried distillers grains with solubles (DDGS) and 10% wheat middlings (midds) was used for all treatments. The 6 treatments were: (1) roller mill– ground corn (737 µ) fed in meal form; (2) treatment 1 fed in pellet form; (3) hammer mill–ground corn (324 µ) fed in meal form; (4) treatment 3 fed in pellet form; (5) complete mixed diet reground through a hammer mill (541 µ) fed in meal form; and (6) treatment 5 in pellet form. Overall (d 0 to 21), ADG and ADFI decreased when corn was finely ground and fed in meal form but increased when fed in pelleted form, resulting in a tendency (P < 0.09) for a diet form × corn particle size interaction. Fine-grinding the complete mixed diet had no effects. Pelleting diets improved (P < 0.04) ADG, F/G, ME and NE energetic efficiencies, and final BW. In conclusion, pelleting diets significantly improved performance, and reducing the particle size of corn from 737 to 324 µ improved nursery pig performance when fed in pelleted form.Item Open Access Influence of a superdose of phytase (Optiphos) on finishing pig performance and carcass characteristics(Kansas State University. Agricultural Experiment Station and Cooperative Extension Service, 2014-04-28) Goodband, Robert D.; Langbein, Kari Beth; Tokach, Michael D.; DeRouchey, Joel M.; Dritz, Steven S.; goodband; mtokach; dritz; jderouchA total of 1,188 finishing pigs (PIC 337 × 1050, initially 80.1 lb) were used in a 92-d experiment to determine the influence of providing phytase above that needed to meet the P requirement for growth performance and carcass characteristics. There were 27 pigs per pen and 11 pens per treatment. Each pen contained a similar number of barrows and gilts. Pens were randomly assigned to treatment based on initial BW. Basal diets contained corn, soybean meal, dried distillers grains with solubles (DDGS), and bakery meal and were formulated to meet or exceed the nutrient requirements of the pigs in each of the four phases. The four dietary treatments were formed by adding increasing levels of phytase (Optiphos 2000, Enzyvia LLC) at 0.25 (control), 0.5, 1.0 and 2.0 lb/ton. Diets were formulated such that the addition of the first 0.25 lb/ton of phytase was needed to meet the P requirement of the pigs, with further additions exceeding the P requirement. Pigs were weighed and feed disappearance was determined approximately every 14 d to determine ADG, ADFI, and F/G. On d 92, pigs were tattooed by pen number and harvested to collect carcass data. Overall (d 0 to 92), increasing dietary phytase did not influence ADG but reduced (cubic, P < 0.01) ADFI, resulting in an improvement in F/G (cubic, P < 0.01). The cubic response occurred because F/G improved as phytase inclusion increased from 0.25 to 0.5 lb/ton, with no further improvement when phytase was increased to 1.0 or 2.0 lb/ton. Phytase addition to the diet did not influence carcass measurements. These results suggest that providing phytase at levels above that needed to meet the pig’s requirement for P has the potential to improve feed efficiency.Item Open Access Feed processing parameters and their effects on nursery pig growth performance(Kansas State University. Agricultural Experiment Station and Cooperative Extension Service, 2014-04-23) Lewis, Landon L.; Jones, Cassandra K.; Fahrenholz, Adam C.; Goncalves, Marcio Antonio Dornelles; Stark, Charles R.; DeRouchey, Joel M.; jonesc; crstark; jderouchA total of 180 nursery pigs (PIC 327 × 1050; initially 27.8 lb) were used in an 18-d study to determine the effects of conditioning parameters and feed form on pig performance. All diets were the same corn, dried distillers grains with solubles (DDGS), and soybean meal-based formulation with different processing parameters used to create the experimental treatments. Treatments included: (1) negative control mash diet, (2) positive control pelleted diet conditioned at 60 rpm, (3) pelleted diet conditioned at 30 rpm and reground, (4) pelleted diet conditioned at 60 rpm and reground, and (5) pelleted diet conditioned at 90 rpm and reground. The different rpm values among treatments represent the time in the conditioner during processing. The lower the rpm value, the longer time feed was in the conditioner. Pigs were weaned and fed a common acclimation diet for 21 d prior to the start of the experiment. Average daily gain and F/G did not differ (P > 0.12) between treatments overall, but ADFI decreased (P = 0.03) for pigs fed the pelleted, positive control diet compared with all other diets. Although no overall treatment effects were significant for ADG or F/G, the experiment was designed more specifically to evaluate treatment differences using preplanned comparisons. When considering preplanned contrasts, we observed that pigs fed mash diets tended to have greater (P = 0.10) ADG than those fed pelleted and reground diets, suggesting that processing may have had a negative influence on feed utilization, a hypothesis that is further supported because pigs fed mash diets tended to have greater (P = 0.06) ADG compared with those fed diets that were heat-processed, regardless of regrinding. Considering these results, it was not surprising that pigs fed mash diets had greater (P = 0.05) ADG and ADFI (P = 0.01) than those fed pelleted diets. When directly comparing diets conditioned at 60 rpm, fed either as whole pellets or reground to mash consistency, pigs fed pelleted diets had improved (P = 0.01) F/G due to lower ADFI (P = 0.004) but similar ADG (P = 0.60). This unexpected negative impact of pelleting on ADG may be due to a negative influence of heat treatment on palatability. The expected improvement in F/G from pelleting (6.8%) was observed but lost when diets were reground to near original mash particle size. This result may indicate that diet form (high-quality pellets vs. mash) affects F/G more than degree of starch gelatinization or other intrinsic factors associated with conditioning ingredients.Item Open Access Evaluating the effects of an algae-modified montmorillonite clay in diets contaminated With deoxynivalenol on nursery pig growth performance(Kansas State University. Agricultural Experiment Station and Cooperative Extension Service, 2014-04-23) Erceg, Jake A.; Frobose, Hyatt L.; Tokach, Michael D.; DeRouchey, Joel M.; Dritz, Steven S.; Goodband, Robert D.; Nelssen, Jim L.; mtokach; jderouch; dritz; goodband; jnelssenA total of 280 nursery pigs (PIC 327 × 1050, initially 21.9 lb and 35 d of age) were used in a 21-d growth trial to evaluate the effects of an algae-modified montmorillonite clay (MMi) on nursery pig performance when fed diets contaminated with deoxynivalenol (DON). Pigs were allotted to pens by weight, and pens were randomly assigned to 1 of 5 dietary treatments arranged in a 2 × 2 + 1 factorial with 7 pigs per pen and 8 pens per treatment. All experimental diets were pelleted. Mycotoxin analyses were conducted on the main ingredients at NDSU3 and LDA labs4, and these results were used in diet formulation. Naturally contaminated wheat (10.7 ppm DON) was used to produce diets with approximately 5 ppm DON. The 5 treatments consisted of 2 positive control diets that did not contain DON contamination with or without 0 or 0.50% MMi and 3 negative control diets that were contaminated with 5 ppm of DON and contained 0, 0.25%, or 0.50% MMi. No DON × MMi interactions were observed for the entire study. Overall (d 0 to 21), ADG, ADFI, and d 21 BW decreased (P < 0.001) in pigs fed DON-contaminated diets regardless of MMi addition. Feed efficiency was poorer (P < 0.001) for pigs fed diets with DON due, primarily to poor feed efficiency in the initial period (d 0 to 7). Pigs fed diets contaminated with DON had greater (P < 0.05) BW variation (CV) within pen on d 21. Although the addition of 0.5% MMi to diets restored (P < 0.02) ADFI from d 14 to 21, no other treatment differences were observed for MMi inclusion. In conclusion, this study suggests that including MMi will not offset reductions in nursery pig performance caused by high DON levels (> 5 ppm) when diets are fed in pellet form.Item Open Access Effects of non-starch polysaccharide enzymes (Roxazyme G2G and/or Ronozyme VP) on growth performance of nursery pigs fed normal or drought-stressed corn(Kansas State University. Agricultural Experiment Station and Cooperative Extension Service, 2014-04-23) Jones, Cassandra K.; Franz, E. L.; Frobose, Hyatt L.; DeRouchey, Joel M.; Goodband, Robert D.; Tokach, Michael D.; Bergstrom, J. R.; jonesc; jderouch; goodband; mtokachA total of 360 barrows (PIC 1050 × 337, initially 12.9 lb BW) were used to determine the effects of non-starch polysaccharide enzymes (Roxazyme G2G and/or Ronozyme VP; DSM Nutritional Products, Inc., Parsippany, NJ) on growth performance and nutrient digestibility of nursery pigs fed normal or drought-stressed corn. Initially, corn samples were collected from 34 separate lots and analyzed to find representatives of normal and drought-stressed corn. These same lots were also used in a separate experiment measuring the impact of drought stress on diet manufacturing characteristics. The lot selected to represent the normal corn had a test weight of 55.9 lb/bu, <5 ppb aflatoxin, 15.0% moisture, and contained 0.77% β-glucan. The lot selected to represent drought-stressed corn had a test weight of 54.3 lb/bu, 6 ppb aflatoxin, 14.3% moisture, and 0.83% β-glucan. Pigs were allotted to pens at weaning (d 0) and were acclimated to a common diet for 10 d prior to the start of this experiment. On d 10 post-placement, pigs were weighed and pens of pigs randomly allotted to 1 of 8 dietary treatments in a completely randomized design. Treatments were arranged in a 2 × 4 factorial with main effects of corn (normal vs. drought-stressed) and enzyme inclusion (none vs. 100 ppm Roxazyme G2G vs. 250 ppm Ronozyme VP vs. 100 ppm Roxazyme G2G + 250 ppm Ronozyme VP). Pigs were fed experimental treatments from d 10 to 35 postweaning in two phases. Feed and fecal samples were collected on d 30 postweaning and analyzed to determine apparent total tract digestibility of nutrients. The nutrient concentrations of normal and drought-stressed corn were similar, which resulted in few treatment or main effects differences of corn type or enzyme inclusion. No interactions were observed (P > 0.24) between corn source and enzyme inclusion. Overall (d 10 to 35), there was no effect on ADG or ADFI, but enzyme inclusion tended to improve (P = 0.09) F/G, which was primarily driven by the improved (P = 0.04) feed efficiency of pigs fed Roxazyme G2G in Phase 1 (d 10 to 25 postweaning). In conclusion, drought stress did not alter the non-starch polysaccharide concentration of corn. Because non-starch polysaccharide substrates were similar across treatments, it was not surprising that enzyme inclusion showed little benefit to nursery pig growth performance; however, improved feed efficiency of pigs fed diets containing Roxazyme G2G from d 10 to 25 postweaning warrants further investigation.
