S.S. Dritz

Kansas State University, Манхэттен, Kansas, United States

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Publications (567)260.26 Total impact

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    ABSTRACT: Two experiments were conducted to determine the effects of increasing the dietary Zn content on growth performance, carcass characteristics, plasma Zn, and ileal mucosal inflammation mRNA expression of finishing pigs fed diets containing ractopamine HCl (RAC; Elanco Animal Health, Greenfield, IN). In Exp. 1, 312 pigs (327 × 1050; PIC, Hendersonville, TN; 94 kg BW) were used in a 27-d study. There were 2 pigs per pen and 26 pens per treatment. Treatments included a corn-soybean meal diet (control; 0.66% standardized ileal digestible [SID] Lys); a diet (0.92% SID Lys) with 10 mg/kg RAC; and the RAC diet plus 50, 100, or 150 mg Zn/kg from ZnO or 50 mg Zn/kg from a Zn AA complex (ZnAA; Availa-Zn; Zinpro, Eden Prairie, MN). All diets also contained 83 mg Zn/kg from ZnSO4 in the trace mineral premix. Pigs fed the RAC diet without added Zn had increased (P < 0.05) ADG, G:F, HCW, carcass yield, and loin weight compared with pigs fed the control diet. Increasing Zn from ZnO in diets containing RAC tended to increase (linear, P = 0.067) G:F and loin weight (quadratic, P = 0.064). Pigs fed diets with 50 mg Zn/kg from ZnAA tended to have increased (P = 0.057) ADG compared with pigs fed the RAC diet. In Exp. 2, 320 pigs (327 × 1050; PIC; 98 kg BW) were used in a 35-d study. There were 2 pigs per pen and 20 pens per treatment. Treatments included a control diet (0.66% SID Lys); a diet (0.92% SID Lys) with 10 mg/kg RAC; or the RAC diet plus 75, 150, and 225 mg Zn/kg from ZnO or ZnAA. All diets also contained 55 mg Zn/kg from ZnSO4 from the trace mineral premix. Pigs fed the RAC diet had increased (P < 0.05) ADG, G:F, HCW, loin depth, percentage lean, and liver weight compared with pigs fed the control diet. No Zn level or source effects or level × source interactions were observed for growth performance. A Zn level × source interaction (quadratic, P = 0.007) was observed in liver Zn concentrations. This resulted from liver Zn concentrations plateauing at 150 mg Zn/kg when ZnO was supplemented, while there was a linear increase when using ZnAA. Increasing Zn in diets containing RAC increased (linear, P < 0.05) plasma Zn on d 18 and 32. The expression of IL-1β was increased (P = 0.014) in mucosa of pigs fed the RAC diet compared with those fed the control diet. Expression of IL-1β decreased (linear, P = 0.026) in the mucosa of pigs fed increasing added Zn. In conclusion, adding Zn to diets containing RAC resulted in a trend for improved growth performance of pigs in 1 of 2 experiments. Also, additional Zn increased plasma Zn and reduced IL-1β.
    Journal of Animal Science 01/2015; 93(1):185-96. DOI:10.2527/jas.2014-8286 · 1.92 Impact Factor
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    ABSTRACT: Abstract Zinc (Zn) is often supplemented at elevated concentrations in swine diets, particularly in piglets, to prevent enteric infections and promote growth. Previous studies from Denmark have suggested a genetic linkage and a phenotypic association between Zn resistance, encoded by czrC, and methicillin-resistance conferred by mecA in Staphylococcus aureus. Such an association has not been reported in the U.S. swine population. We conducted an analysis of the effects of Zn, supplemented as zinc oxide (ZnO), on the nasal carriage of methicillin-resistant Staphylococcus aureus (MRSA) in nursery (n=40) and finisher pigs (n=40) enrolled in a nutritional study. Nasal swabs, collected from nursery and finisher pigs, were inoculated onto MRSA CHROMagar and presumptive MRSA colonies were tested for the presence of mecA and czrC genes by polymerase chain reaction. Zinc susceptibility was determined by the agar dilution method. The prevalence of mecA-positive MRSA was 10% (4/40) and 20% (8/40) among nursery and finisher pigs, respectively. Of the 12 mecA-positive S. aureus isolates, 7 had the czrC gene (58.3%) compared to none among the 68 mecA-negative isolates. The presence of both mecA (p=0.002) and czrC (p=0.006) genes were positively associated with higher levels of Zn supplementation. The median minimum inhibitory concentrations of Zn for czrC-positive and czrC-negative isolates were 12 and 2 mM, respectively (p<0.0001). The link between czrC and mecA genes suggests the importance of elevated Zn supplementation in the co-selection and propagation of methicillin resistance among S. aureus in pigs.
    Foodborne Pathogens and Disease 12/2014; 12(2). DOI:10.1089/fpd.2014.1851 · 2.28 Impact Factor
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    ABSTRACT: A total of 126 gilts and sows (PIC 1050) and their litters were used to determine the effects of dietary vitamin E concentration and source on sow plasma, milk, and pig concentrations of α-tocopherol. Additionally, we estimated the bioavailability of D-α-tocopheryl acetate (D-α-TAc) relative to DL-α-tocopheryl acetate (DL-α-TAc) when fed in diets containing dried distillers grains with solubles (DDGS). The 6 dietary treatments included DL-α-TAc at 44 and 66 mg/kg and D-α-TAc at 11, 22, 33, and 44 mg/kg. From breeding to d 69 of gestation, sows were fed 2.0 kg/d of a diet containing 40%-DDGS, 0.30 mg/kg added Se, and no added vitamin E. Vitamin E treatments were fed from d 70 of gestation through weaning. Plasma was collected from sows on d 69 and 100 of gestation, at farrowing, and at weaning. Colostrum and milk samples were also collected. Plasma from 3 pigs per litter and heart and liver samples from 1 pig per litter were collected at weaning. Plasma, milk, and tissues from 6 litters per treatment were analyzed for α-tocopherol. Although tissue, plasma, and milk concentrations of α-tocopherol were the primary response criteria of interest, sow and litter performance were measured. As expected, treatment effects were not observed (P > 0.10) for lactation feed intake, sow BW, or backfat measurements. A trend (P = 0.085) for a treatment effect on average pig BW at weaning was detected, with pigs nursing sows fed 44 mg/kg DL-α-TAc weighing less because of a younger weaning age. No other differences in litter performance were observed (P > 0.10). As D-α-TAc increased in the diet, sow plasma, colostrum, milk, pig plasma, and pig heart concentrations of α-tocopherol increased (linear, P < 0.03). Sows fed diets with 44 mg/kg D-α-TAc had increased (P < 0.03) plasma, colostrum, and pig plasma concentrations of α-tocopherol compared with sows fed 44 mg/kg of DL-α-TAc. Sows fed 66 mg/kg DL-α-TAc also had greater (P = 0.022) plasma α-tocopherol at weaning than sows fed 44 mg/kg DL-α-TAc. Bioavailability coefficients for D-α-TAc relative to DL-α-TAc ranged from 1.9 to 4.2 for sow and pig plasma α-tocopherol, 2.9 to 3.6 for colostrum α-tocopherol, 1.6 for milk α-tocopherol, and 1.7 to 2.0 for pig heart and liver α-tocopherol. Overall, this study indicates that the relative bioavailability for D-α-TAc relative to DL-α-TAc varies depending on the response criteria but is greater than the standard potency value of 1.36.
    Journal of Animal Science 09/2014; 92(10). DOI:10.2527/jas.2013-7311 · 1.92 Impact Factor
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    ABSTRACT: A total of 576 mixed-sex pigs (PIC 327 × 1050; initial BW = 55.8 ± 5.5 kg) were used to determine the effects of corn dried distillers grains with solubles (DDGS) and wheat middlings (midds) withdrawal 24 d before harvest in diets without or with ractopamine HCl (RAC) on growth performance, carcass characteristics, and carcass fat quality. From d 0 to 49, pigs were fed a corn-soybean meal-based diet (CS) or a diet high in unsaturated fat and crude fiber provided by 30% DDGS and 19% wheat midds (HFF) and not balanced for energy. On d 49, pens of pigs previously fed CS diets remained on the CS diet. Half of the HFF-fed pigs were switched to the CS-based diets, which served as the withdrawal regimen. Finally, half of the HFF-fed pigs remained on the same HFF diet. All 3 regimens were fed without or with 10 ppm RAC. There were 12 pens per treatment with 8 pigs per pen. No significant diet regimen × RAC interactions were observed. From d 0 to 49, pigs fed the CS diet had increased (P < 0.001) ADG and G:F compared with pigs fed the HFF diet. Overall (d 0 to 73), pigs fed the CS diets throughout had greater (P < 0.001) ADG and G:F than those fed the HFF diets throughout. Pigs fed the withdrawal diets had greater (P = 0.014) ADG, but similar G:F to those fed the HFF diets throughout. Pigs fed the CS diets throughout had greater (P = 0.025) carcass yield compared with pigs fed the HFF diets throughout, with those fed the withdrawal diets intermediate. Pigs fed RAC had greater (P < 0.001) ADG, G:F, and carcass yield (P = 0.061than pigs not fed RAC. Jowl, backfat, belly, and leaf fat iodine value (IV) were lowest (P < 0.001) for pigs fed the CS diets, highest (P < 0.015) for those fed HFF diets throughout, and intermediate for pigs fed the withdrawal diet. There were no differences in either full or rinsed intestine or organ weights between pigs that were fed CS diets throughout and pigs fed the withdrawal diet; however, pigs fed the HFF diets throughout the study had increased (P = 0.002) rinsed cecum and full large intestine weights (P = 0.003) compared with the pigs fed the withdrawal diets. Withdrawing the HFF diet and switching to a CS diet for the last 24 d before harvest partially mitigated negative effects on carcass yield and IV often associated with high-fat, high-fiber ingredients such as DDGS and wheat midds. Feeding RAC for the last 24 d before market, regardless of dietary regimen, improved growth performance and carcass yield.
    Journal of Animal Science 09/2014; 92(10). DOI:10.2527/jas.2014-7434 · 1.92 Impact Factor
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    ABSTRACT: Three experiments were conducted to compare the effects of a conventional dry (five 30.5-cm spaces 152.4 cm wide; Staco Inc., Schaefferstown, PA) vs. a wet-dry (double sided; each side = 38.1-cm space; Crystal Spring; GroMaster Inc., Omaha, NE) finishing feeder (Exp. 1 and 2) and to evaluate the effects of feeder design and dietary level of dried distillers' grains with solubles (DDGS; >10% oil; Exp. 3) on performance and carcass characteristics of finishing pigs. In Exp. 1, 1,186 pigs (32.1 kg BW) were used in a 69-d experiment. There were 26 to 28 pigs per pen and 22 pens per feeder design, and all pigs received the same diets in 4 phases. In Exp. 2, 1,236 pigs (28.7 kg BW) were used in a 104-d experiment, with 25 to 28 pigs per pen and 23 pens per feeder design, and all pigs received the same diets in 5 phases. Carcass measurements were obtained from 11 pens of each feeder design after harvest. In Exp. 3, 1,080 pigs (35.1 kg BW) were used in a 99-d 2 × 2 factorial with main effects of feeder design (dry vs. wet-dry feeders) and DDGS (20 vs. 60%) with 10 pens of 27 pigs per treatment and all diets fed in 4 phases. Jowl fat samples were collected from 2 pigs per pen for fatty acid analysis and iodine value (IV) determination. In all experiments, pigs fed with the wet-dry feeder had greater (P < 0.05) ADG, ADFI, and final BW. In Exp. 2 and 3, HCW and backfat depth were increased (P < 0.05) for pigs fed with a wet-dry feeder, but G:F and fat-free lean index (FFLI) were reduced. Jowl IV was also reduced (P < 0.05) with a wet-dry feeder in Exp. 3. Pigs fed 60% DDGS in Exp. 3 had decreased (P < 0.05) ADG, G:F, final BW, HCW, and backfat but increased jowl IV and a tendency (P < 0.07) toward greater FFLI regardless of feeder type. In conclusion, pigs fed with this specific type of wet-dry feeder had improved ADG and ADFI, poorer G:F, and increased backfat depth compared to pigs fed with a conventional dry feeder. The poorer growth performance and increased jowl IV of pigs fed diets with 60% DDGS was similarly exhibited for pigs fed on both feeders.
    Journal of Animal Science 08/2014; 92(8):3591-7. DOI:10.2527/jas.2014-7686 · 1.92 Impact Factor
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    ABSTRACT: A total of 1,480 pigs were used in 3 experiments to determine the effects of corn distillers dried grains with solubles (DDGS) varying in oil content on growth performance, carcass traits, and nutrient digestibility in finishing pigs. In Exp. 1, 1,198 pigs (PIC Line 337 × 1050; initially 46.1 kg) were allotted to a corn-soybean meal-based diet or diets with 20 or 40% of a 5.4% oil DDGS (29.5% CP, 8.9% ADF, and 21.8% NDF; as-fed basis) or a 9.6% oil DDGS (29.6% CP, 15.3% ADF, and 28.6% NDF; as-fed basis). From d 0 to 82, ADG was unaffected by DDGS source or level. However, increasing 5.4% oil DDGS decreased (linear, P < 0.01) G:F, whereas G:F did not change among pigs fed 9.6% oil DDGS (DDGS source × level interaction; P < 0.01). 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, 270 pigs (PIC Line 327 × 1050; initially 46.5 kg) were allotted a corn-soybean meal-based diet or diets with 20 or 40% of a 9.4% oil DDGS (29.4% CP, 19.6% ADF, and 34.5% NDF; as-fed basis) or a 12.1% oil DDGS (28.5% CP, 17.6% ADF, and 31.4% NDF; as-fed basis). From d 0 to 75, ADG increased and then decreased for pigs fed 9.4% oil DDGS but was unchanged 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 increase G:F. 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 (96.6% corn and 3.4% vitamins and minerals) or a DDGS diet with 50% basal diet and 50% DDGS. On an as-fed basis, corn contained 3,871 and 3,515 kcal/kg GE and DE, respectively. The 5.4, 9.6, 9.4, and 12.1% oil DDGS contained 4,347, 4,648, 4,723, and 4,904 kcal/kg (as-fed basis) GE and 3,417, 3,690, 3,838, and 3,734 kcal/kg DE, respectively (as-fed basis). Stepwise regression indicated that the oil (ether extract) content was the only significant variable to explain differences in energy content. The equations generated to predict DE and NE as a function of oil content on an as-fed basis were DE (kcal/kg) = 62.347 × ether extract (%) + 3,058.13 (n = 5, adjusted R(2) = 0.41) and NE (kcal/kg) = 115.011 × ether extract (%) + 1,501.01 (n = 5, adjusted R(2) = 0.86).
    Journal of Animal Science 08/2014; 92(8):3610-23. DOI:10.2527/jas.2014-7678 · 1.92 Impact Factor
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    ABSTRACT: Abstract Text: A total of 1,248 pigs (initially 28.9 kg BW) were used in a 120-d study to determine the effects of added tribasic copper chloride (TBCC; IntelliBond C; Micronutrients, Indianapolis, IN) and increasing standardized ileal digestible Lys on growth performance, carcass characteristics, liver Cu concentration, and carcass fat quality in finishing pigs. Pens of pigs were allotted to 1 of 6 dietary treatments, balanced on average pen weight in a randomized complete block design with 26 pigs per pen and 8 replications per treatment. Treatments were arranged in a 3×2 factorial with main effects of SID Lys (85, 92.5, and 100% of the estimated requirement) and added Cu (0 or 150 ppm) from TBCC. All diets were corn-soybean meal-based with 30% distiller’s dried grains with solubles, 15% bakery meal and 17 ppm Cu from CuSO4 provided from the trace mineral premix. There were no TBCC × SID Lys interactions observed for growth performance or liver Cu concentrations. Increasing SID Lys increased (P< 0.01) ADG, G:F and final BW (Table 1). Pigs fed 150 ppm TBCC tended (P<0.10) to have increased ADG, G:F and final BW. Liver Cu concentrations were greater (P<0.01) in pigs fed TBCC and tended to decrease (quadratic; P<0.09) as SID Lys increased. In pigs fed TBCC, jowl fat iodine value (IV) calculated from the fatty acid analysis of all 3 fat layers, increased with increasing SID Lys but not in pigs fed diets without TBCC (Lys × TBCC interaction; P<0.03). In summary, SID Lys did not influence the response to TBCC is this experiment. Table 1. Dietary SID lys level with or without tribasic copper chloride in finishing pigs. TBCC, ppm Probability, P <1 0 150 SID Lys SID Lys, % 85.0 92.5 100.0 85.0 92.5 100.0 TBCC Linear Quadratic d 120 BW, kg 122.8 125.4 126.2 123.7 125.8 129.0 0.07 0.01 0.76 ADG, kg 0.80 0.81 0.82 0.80 0.82 0.84 0.10 0.01 0.74 ADFI, kg 2.18 2.20 2.19 2.19 2.19 2.23 0.65 0.23 0.95 G:F 0.365 0.370 0.373 0.365 0.374 0.380 0.09 0.01 0.58 Liver Cu, ppm 13 13 12 33 33 26 0.01 0.18 0.09 Jowl IV2 84.2 84.6 83.6 82.7 83.6 85.5 0.74 0.16 0.87 1SEM were 1.52, 0.007, 0.032, 0.004, 3.3, and 0.801 for d 120 BW, ADG, ADFI, G:F, liver Cu, and jowl IV respectively. 2Linear TBCC × Lys interaction (P<0.03). Keywords: finishing pig, copper, lysine, iodine value
    2014 ADSA-ASAS-CSAS Joint Annual Meeting; 07/2014
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    ABSTRACT: Abstract Text: A total of 1,197 pigs (PIC 337 × 1050) were used in a 72-d study to determine the effects of added Zn from ZnO fed during the grower (d 0-45; initially 58.8 kg) and finisher (d 45-72; initially 99.0 kg) in diets with or without ractopamine HCl (RAC; Elanco Animal Health, Greenfield, IN) on growth performance and carcass characteristics. There were 25 pigs per pen and 6 pens per treatment. Pens were randomly assigned to a 2×2×2 factorial arrangement in a split-plot design. The whole plot consisted of diets with or without 75 ppm added Zn from d 0 to 45 and the subplots were diets with or without 75 ppm added Zn and with or without 10 ppm RAC from d 45 to72. All diets contained 50 ppm Zn supplied from the premix. No interactions were observed. Addition of 75 ppm Zn during either period or both did not influence pig growth performance or carcass characteristics. Pigs fed RAC had improved (P<0.03) ADG, G:F, final BW, HCW, loin depth, and fat-free lean index compared with pigs fed the control diet. In conclusion, feeding RAC improved the performance of grow-finish pigs; however, additional Zn did not. Keywords: growing-finishing pigs, ractopamine HCl, zinc Table 1. Effects of added zinc during the grower and/or finisher phase on growth performance and carcass characteristics of finishing pigs fed diets with or without ractopamine HCl Added Zn d 0-45: - - - - + + + + Added Zn d 45-72: - + - + - + - + Added RAC d 45-72: - - + + - - + + SEM d 0 to 72 ADG, kg 0.89 0.88 0.95 0.95 0.89 0.88 0.97 0.96 0.01 ADFI, kg 2.65 2.60 2.60 2.63 2.69 2.68 2.71 2.72 0.05 G:F 0.34 0.34 0.37 0.36 0.33 0.33 0.36 0.35 0.00 Final BW, kg 118.7 118.0 122.9 123.6 119.4 118.0 124.0 124.2 2.7 Carcass Characteristics HCW, kg 86.0 86.0 88.2 90.0 85.4 87.1 88.7 89.5 2.2 Yield,1 % 74.09 74.12 74.64 75.35 73.09 75.52 73.98 74.08 1.35 Backfat thickness,2 mm 16.75 15.69 13.81 14.86 16.29 16.28 14.13 13.67 0.63 Loin depth,2 mm 62.64 61.71 64.59 63.12 61.99 61.58 65.52 66.06 1.13 FFLI,2 % 53.13 53.70 55.13 55.13 53.52 53.33 55.01 55.94 0.57 1Calculated by dividing HCW by live weight obtained at the packing plant. 2Adjusted using HCW as a covariate.
    2014 ADSA-ASAS-CSAS Joint Annual Meeting; 07/2014
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    ABSTRACT: Abstract Text: A total of 288 pigs (43.8 kg BW) were used in an 83-d trial to determine the effects of hard red winter wheat particle size on finishing pig growth performance and caloric efficiency. Caloric efficiency (CE) was calculated using the ingredient energy values from NRC (2012) ME and INRA (2004) NE. Pigs were allotted to 1 of 3 dietary treatments with 6 pens/treatment and 8 pigs/pen. The same wheat-soybean meal–based diets were used for all treatments. Diets were fed in mash form. The 3 dietary treatments included hammer-mill ground wheat to particle sizes of: 1) 728; 2) 579; and 3) 326 µm, respectively. From d 0 to 40, decreasing wheat particle size decreased (linear; P<0.03) ADFI (2.29, 2.24, 2.20 kg), but improved (quadratic; P<0.01) G:F (0.400, 0.413, 0.409) and CE (7.89, 7.65, 7.72 Mcal ME/kg) and (5.84, 5.66, 5.71 Mcal NE/kg) basis, with no change (P>0.24) in ADG (0.92, 0.93, 0.90 kg/d). From d 40 to 83, decreasing wheat particle size increased (quadratic; P<0.01) ADG (0.92, 0.90, 0.95 kg/d), and improved (linear; P<0.01) G:F (0.319, 0.322, 0.336) and CE (9.92, 9.83, 9.44 Mcal ME/kg and 7.45, 7.38, 7.08 Mcal NE/kg), with no change (P>0.23) in ADFI (2.87, 2.80, 2.84). Overall from d 0 to 83, reducing wheat particle size improved (linear; P<0.01) G:F and CE on both an ME and NE basis, with no difference in ADG or ADFI. Fine grinding wheat was detrimental to feed intake in early finishing but improved ADG in late finishing and G:F for both periods and overall. Effects of hard red winter wheat particle size on finishing pig growth performance and caloric efficiency Wheat particle size, µm Probability P < d 0 to 83, 728 579 326 SEM Linear Quadratic ADG, kg 0.92 0.91 0.93 0.01 0.47 0.50 ADFI, kg 2.59 2.53 2.53 0.03 0.13 0.43 G:F 0.354 0.361 0.367 0.002 0.01 0.82 Caloric efficiency, Mcal/kg gain ME 8.94 8.76 8.62 0.06 0.01 0.75 NE 6.67 6.53 6.43 0.05 0.01 0.75 Keywords: finishing pig, particle size, wheat
    2014 ADSA-ASAS-CSAS Joint Annual Meeting; 07/2014
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    ABSTRACT: Abstract Text: A total of 240 weaned pigs (PIC 1050; initially 6.08 ± 0.60 kg) were used in a 47-d study to compare the effects of added Zn from ZnO, alone or in combination with a low or high dose of chlortetracycline (CTC) on nursery pig growth performance. Pigs were allotted to pens at weaning (d 0) and fed a common starter diet with no antimicrobial for 5 d before the start of the experiment. On d 5, pens of 5 pigs were allotted to 1 of 6 dietary treatments, balanced on average pen weight in a randomized complete block design with 8 replications per treatment. Dietary treatments were arranged in a 2 × 3 factorial with main effects of added ZnO (0 vs. 2,500 ppm of Zn) and CTC (0, 55, or 441 mg/kg feed). Pigs were fed experimental diets from d 5 to 26 after weaning followed by a common corn-soybean meal-based diet without antimicrobial from d 26 to 47. Pigs on the 55 mg/kg treatment received CTC continuously from d 5 to 26; however, to comply with FDA guidelines, CTC was removed from the diets of pigs fed 441 mg/kg CTC on d 15, then added again from d 16 to 26. All diets contained at least 110 ppm of Zn from ZnO in the trace mineral premix. No ZnO × CTC interactions were observed. Pigs fed added ZnO had increased (P=0.001) ADG, ADFI, and BW during the treatment period but decreased G:F (P=0.025) from d 26 to 47 when a common diet was fed. Overall (d 5 to 47), pigs fed added ZnO had increased (P<0.05) ADG and ADFI. Pigs fed CTC had increased (linear, P<0.05) ADG, ADFI, and BW during the treatment period. Overall, pigs fed CTC tended to have increased (linear, P<0.10) ADG and ADFI, but G:F tended (quadratic, P=0.070) to increase then decrease as CTC increased. In summary, ZnO and CTC increased ADG and ADFI but had a minimal effect on feed efficiency. Table 1. Effect of zinc oxide and chlortetracycline on pig growth. Added Zn, ppm 0 0 0 2,500 2,500 2,500 CTC, mg/kg 0 55 441 0 55 441 SEM d 5 to 26 ADG, g 355 378 386 397 397 417 7.9 ADFI, g 504 514 528 549 542 570 11.9 G:F 0.705 0.737 0.731 0.725 0.734 0.732 0.0128 Keywords: nursery pig, zinc, chlortetracycline
    2014 ADSA-ASAS-CSAS Joint Annual Meeting; 07/2014
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    ABSTRACT: Abstract Text: A total of 1,232 pigs (PIC 337 × 1050; initially 27.0 ± 0.51 kg) were used in a 98-d study to determine the influence of high doses of added nicotinic acid (NA) on growth, carcass traits, and meat quality of finishing pigs during the summer months. Average daily high, mean, and low temperatures were 27.5, 23.9, and 20.5° C, respectively. There were 28 pigs per pen and 11 replications per treatment. Four dietary treatments were made by adding 0, 350, 700, or 1,050 mg/kg NA (Lonza, Allendale, NJ) to a corn-soybean meal basal diet that contained 30 mg/kg of added NA. Diets were fed in 4 phases with the same NA concentrations in each phase. On d 98 of the study, 2 pigs per pen (1 barrow and 1 gilt) were transported to a commercial abattoir. Carcass traits and pH decline (45 min, 3, and 21 h) were measured at the abattoir. Afterwards, a 40 cm segment of boneless LM was used to determine purge loss and ultimate pH following a 10 d aging period. Then 2.5 cm boneless chops were cut and used to measure subjective color and marbling, objective color (L*, a*, b*), 24 h drip loss, and NA concentration. Overall (d 0 to 98), increasing NA had no effect on ADG or G:F; however, ADFI tended (P = 0.07) to increase. Carcass traits were not influenced by NA. Forty-five min and 21 h pH were decreased with increasing NA (P < 0.01); but ultimate pH was not different. Purge loss, drip loss, and NA concentrations were not influenced by treatment. The a* and b* were increased (P < 0.05) with increasing NA; however, subjective color scores were not different among treatments. Overall, high doses of NA had little influence on growth, carcass traits, and meat quality of finishing pigs raised in a commercial setting. Table 1. Effects of added dietary NA on growth and meat quality of finishing pigs. Dietary NA, mg/kg Probability, P < Item 30 380 730 1,080 SEM Linear Quadratic d 0 to 98 ADG, kg 0.82 0.82 0.83 0.82 0.005 0.40 0.50 ADFI, kg 2.03 2.08 2.10 2.07 0.017 0.07 0.71 G:F 0.404 0.395 0.393 0.398 0.003 0.15 0.90 L* 53.12 54.67 54.56 54.16 0.82 0.54 0.21 a* 18.20 18.30 18.89 19.05 0.39 0.05 0.58 b* 16.05 16.45 16.88 17.09 0.40 0.04 0.89 Keywords: finishing pigs, niacin, nicotinic acid
    2014 ADSA-ASAS-CSAS Joint Annual Meeting; 07/2014
  • The Professional Animal Scientist 07/2014; 30(4):375-392. DOI:10.15232/pas.2013-01297
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    ABSTRACT: Abstract Text: Iodine value (IV) is a measure of unsaturated fatty acids and is currently the industry standard for assessing pork fat quality. The objective of this meta-analysis was to use data from existing literature to generate equations to predict back, belly, and jowl fat IV of finishing pigs. The final database resulted in 24 papers with 169 observations for backfat IV, 21 papers with 124 observations for belly fat IV, and 29 papers with 197 observations for jowl fat IV. Some observations (back n=36, belly n=37, and jowl n=45) changed dietary fatty acid composition during the experiment (i.e. switching from higher to lower or lower to higher iodine value product diet), where initial diets (I) were defined as those fed before the change in diet composition and final diets (F) were defined as those fed after the change in diet composition. The predictor variables tested were divided into 5 groups: 1) diet fat composition (dietary percent C16:1, C18:1, C18:2, C18:3, EFA, and unsaturated fatty acids, and iodine value product) for both I and F diets; 2) duration of feeding of the I and F diets; 3) ME or NE content of the I and F diet; 4) performance criteria (initial BW, final BW, ADG, ADFI, and G:F); 5) carcass criteria (HCW and backfat thickness). PROC MIXED (SAS institute, Inc., Cary, NC) was used to develop regression equations, and experiment within paper was included as a random effect. Statistical significance for including terms in the models was determined at P<0.10. Evaluation of models with significant terms was then conducted based on the Bayesian Information Criterion (BIC), where the lowest BIC were preferred. Optimum equations to predict back (BIC=739), belly (BIC=558), and jowl (BIC=758) fat IV were: backfat IV =84.83+(6.87*I EFA)-(3.90*F EFA)-(0.12*I d)-(1.30*F d)-(0.11*I EFA*F d)+(0.048*F EFA*I d)+(0.12*F EFA*F d)-(0.0060*F NE)+(0.0005*F NE*F d)-(0.26*backfat depth); belly fat IV = 106.16+(6.21*I EFA)-(1.50*F d)-(0.11*I EFA*F d)-(0.012*I NE)+(0.00069*I NE*F d)-(0.18*HCW)-(0.25*BF); and jowl fat IV =85.50+(1.08*I EFA)+(0.87*F EFA)-(0.014*I d)-(0.050*F d)+(0.038*I EFA*I d)+(0.054*F EFA*F d)-(0.0066*I NE)+(0.071*I BW)-(2.19*ADFI)-(0.29*backfat depth). These regression equations may be used to predict the back, belly, and jowl fat IV of finishing pigs fed different diets. Keywords: Iodine value, meta-analysis, pork quality
    2014 ADSA-ASAS-CSAS Joint Annual Meeting; 07/2014
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    ABSTRACT: The effects of feed withdrawal time before slaughter on finishing pig carcass composition were evaluated in 2 studies. In Exp. 1, 728 pigs (BW = 128.9 ± 1.2 kg) were allotted to 1 of 4 treatments in a randomized design with NUMBER OF PIGS PER PEN AND LOCATION WITHIN BARN BALANCED ACROSS TREATMENT: The 4 treatments were feed withdrawal times of 8, 24, 36, or 48 h AND THERE WERE 12 REPLICATE PENS PER TREATMENT: .
    Journal of Animal Science 07/2014; 92(8). DOI:10.2527/jas.2013-7367 · 1.92 Impact Factor
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    ABSTRACT: Four experiments were conducted to examine effects of dietary wheat middlings (MIDDS: ), corn dried distillers grains with solubles (DDGS: ), and NE formulation on nursery pig performance and caloric efficiency. In Exp. 1, 180 nursery pigs (11.86 ± 0.02 kg BW and 39 d of age) were fed 1 of 5 diets for 21 d, with 6 pigs per pen and 6 replications per treatment. Diets were corn-soybean meal-based and included 0, 5, 10, 15, or 20% midds. Increasing midds decreased (linear; P < 0.05) ADG and ADFI. Caloric efficiency improved (linear; P < 0.05) on both an ME (NRC, 1998) and NE (INRA, 2004) basis as dietary midds increased. In Exp. 2, 210 pigs (6.85 ± 0.01 kg BW and 26 d age) were fed 1 of 5 diets for 35 d, with 7 pigs per pen and 6 replications per treatment. Diets were corn-soybean meal-based and contained 0, 5, 10, 15, or 20% midds. Increasing midds did not affect overall ADG or ADFI, but decreased (quadratic; P < 0.013) G:F at 20%. Caloric efficiency for both ME and NE improved (quadratic; P < 0.05) as dietary midds increased. In Exp. 3, 180 pigs (12.18 ± 0.4 kg BW and 39 d of age) were fed 1 of 6 experimental diets arranged in a 2 × 3 factorial with main effects of DDGS (0 or 20%) and midds (0, 10, or 20%) for 21 d, with 6 pigs per pen and 5 replications per treatment. No DDGS × midds interactions were observed, and DDGS did not influence ADG, ADFI, or G:F, but increasing dietary midds decreased (linear; P < 0.05) ADG, G:F, and final BW. In Exp. 4, 210 pigs (6.87 kg BW and 26 d of age) were allotted to 1 of 5 dietary treatments, with 7 pigs per pen and 6 replications per treatment. Wheat middlings (0, 10, or 20%) were added to the first 3 diets without balancing for energy. In diets 4 and 5, soybean oil was added (1.4 and 2.8%) to 10 and 20% midds diets to balance to the same NE as the positive control (0% midds). Overall, no midds × fat interactions occurred. Regardless of formulated energy value, caloric efficiency and G:F was poorer (P < 0.05) on an ME basis as midds increased from 10 to 20% of the diet but did not change when calculated on an NE basis. Results of these experiments indicate that midds may be fed up to 10 to 15% of the diet without negatively affecting nursery pig performance and with no interactive effects when fed in combination with DDGS. Also, formulating on an NE basis provided for similar performance with increasing dietary midds compared with a corn soybean-meal control diet.
    Journal of Animal Science 07/2014; 92(8). DOI:10.2527/jas.2013-7350 · 1.92 Impact Factor
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    ABSTRACT: Two experiments were conducted to investigate the effects of sodium sulfate water and the efficacy of non-nutritive feed additives in nursery pig diets. In Exp. 1, 320 barrows (5.4 ± 0.1 kg BW and 21 d of age) were allotted to 1 of 8 treatments for 24 d in a 2 × 4 factorial with 2 levels of sodium sulfate water (control or 3,000 mg sodium sulfate/L added), and 4 dietary zeolite (clinoptilolite) levels (0, 0.25, 0.50, or 1%). Fecal samples were collected on d 5, 9, 16, and 23; visually scored for consistency (1 = firm, 5 = watery); and analyzed for DM. No interactions of sodium sulfate × zeolite were observed for any response criteria. Overall (d 0 to 24), pigs drinking sodium sulfate water had decreased (P < 0.01) ADG, ADFI, and G:F compared with pigs drinking control water. Pigs drinking sodium sulfate water also had increased (P < 0.01) fecal scores and lower (P < 0.04) fecal DM on d 5, 9, and 16, compared with pigs drinking control water. Increasing dietary zeolite increased (linear, P < 0.05) ADG and ADFI but had no effect on G:F. In Exp. 2, 350 barrows (5.7 ± 0.1 kg BW and 21 d of age) were allotted to 1 of 10 treatments in a 2 × 5 factorial for 21 d with 2 levels of sodium sulfate water (control or 2,000 mg sodium sulfate/L added) and 5 dietary treatments (control, 1 or 2% zeolite, 1% humic acid substance [HA], and 1% humic and fulvic acid substance [HFB]). Fecal samples were collected on d 5, 8, 15, and 21; visually scored for consistency (1 = firm, 5 = watery); and analyzed for DM. Overall (d 0 to 21), a water source × diet interaction was observed for ADG and G:F because pigs fed the 1% HA had decreased (P < 0.01) ADG and G:F when drinking sodium sulfate water compared with other treatments, but increased ADG and G:F when drinking control water. Pigs drinking sodium sulfate water had decreased (P < 0.01) ADG and G:F and tended (P < 0.08) to have decreased ADFI compared with pigs drinking control water. Pigs drinking sodium sulfate water had increased (P < 0.01) fecal scores and decreased (P < 0.01) fecal DM on d 5 and 8. In conclusion, water high in sodium sulfate concentrations decreased growth performance and increased fecal moisture in newly weaned pigs. Although zeolite improved growth performance in the first experiment, it did not influence growth in the second study. The non-nutritive feed additives used in both experiments were unsuccessful in ameliorating the increased osmotic diarrhea observed from high sodium sulfate water.
    Journal of Animal Science 06/2014; 92(8). DOI:10.2527/jas.2013-7436 · 1.92 Impact Factor
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    ABSTRACT: Feed-grade chlortetracycline (CTC) and copper are both widely utilized in U.S. pig production. Cluster randomized experiment was conducted to evaluate the effects of CTC and copper supplementation in weaned pigs on antimicrobial resistance (AMR) among fecal Escherichia coli. Four treatment groups: control, copper, CTC, or copper plus CTC were randomly allocated to 32 pens with five pigs per pen. Fecal samples were collected weekly from three pigs per pen for six weeks. Two E. coli isolates per fecal sample were tested for phenotypic and genotypic resistance against antibiotics and copper. Data were analyzed with multilevel mixed effects logistic regression, multivariate probit analysis and discrete time survival analysis. CTC-supplementation was significantly (99% [95% CI = 98-100%]) associated with increased tetracycline resistance compared to the control group (95% [95% CI = 94-97%]). Copper supplementation was associated with decreased resistance to most of the antibiotics tested, including cephalosporins, over the treatment period. Overall, 91% of the E. coli isolates were multidrug resistant (MDR) (resistant to ≥3 antimicrobial classes). tetA and blaCMY-2 genes were positively associated (P < 0.05) with MDR categorization, while tetB and pcoD were negatively associated with MDR. tetA and blaCMY-2 were positively associated with each other and in turn, these were negatively associated with both tetB and pcoD genes; which were also positively associated with each another. Copper minimum inhibitory concentration was not affected by copper supplementation or by pcoD gene carriage. CTC supplementation was significantly associated with increased susceptibilities of E. coli to copper (HR = 7 [95% CI = 2.5–19.5]) during treatment period. In conclusion, E. coli isolates from the nursery pigs exhibited high levels of antibiotic resistance, with diverse multi-resistant phenotypic profiles. The roles of copper supplementation in pig production, and pco-mediated copper resistance among E. coli in particular, need to be further explored since a strong negative association of pco with both tetA and blaCMY-2 points to opportunities for selecting a more innocuous resistance profile.
    Preventive Veterinary Medicine 06/2014; DOI:10.1016/j.prevetmed.2014.02.010 · 2.51 Impact Factor
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    ABSTRACT: A total of 320 finishing pigs (PIC 327 × 1050; initially 98 kg) were used 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 randomly selected from each treatment (n = 20) were evaluated using contrasts: CON vs RAC+, interaction of Zn level × source, Zn level linear and quadratic polynomials, and Zn source. There were no Zn source effects or Zn source × level interactions throughout the study (P > 0.10). Pigs fed RAC+ had increased (P < 0.02) percentage type IIX and a tendency for increased (P = 0.10) percent 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 compared to 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 on d 1 and 4 of display and tended to have decreased (P < 0.10) a* values on d 0 and 2 compared to CON pork chops. RAC+ treated pork chops had a tendency for increased (P < 0.08) oxymyoglobin percentage compared to CON pork chops on d 1, 2, 4, and 5. On d 0, as dietary Zn increased in RAC+ diets, there was a decrease (linear, P < 0.01) in the formation of pork chop surface oxymyoglobin percentage. 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 with increasing Zn in RAC diets and treatments did not affect tenderness as measured by Warner-Bratzler shear force (P > 0.07). In conclusion, RAC+ diets produced chops that were lighter and less red, but maintained a greater 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.
    Journal of Animal Science 03/2014; 92(5). DOI:10.2527/jas.2013-7318 · 1.92 Impact Factor
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    ABSTRACT: A total of 1,360 pigs were used in a 125-d study to determine the effects of corn dried distillers grains with solubles (DDGS) withdrawal after immunological castration (Improvest®, Zoetis , Kalamazoo, MI) on growth performance and carcass fat quality of pigs. Pens of male pigs (initially 24 kg) were randomly allotted by BW and castration method (physically castrated [PC] or immunologically castrated [IC] barrows) to 1 of 3 diets with 8 replications per treatment with 27 to 29 pigs per pen. Treatments were arranged in a 2 × 3 factorial with main effects of castration method and diet (0% DDGS throughout, 30% DDGS throughout, or 30% DDGS through d 75 then no DDGS to d 125). Intact males were injected with Improvest on d 39 and 74 (IC). No castration method × diet interactions (P > 0.12) were observed for growth performance. Before the second Improvest injection (d 0 to 74), PC barrows had increased (P < 0.05) ADFI but were less efficient (P < 0.05) than intact males. After the second Improvest injection until the first marketing event (d 74 to 107), IC barrows had improved (P < 0.05) ADG and G:F compared with PC barrows. From d 0 to 107, IC barrows had improved (P < 0.05) ADG, G:F, and lower ADFI than PC barrows. The inclusion of 30% DDGS decreased (P < 0.05) G:F compared with pigs fed the control diet. For the period after the second Improvest injection (d 74 to 125), IC barrows had increased (P < 0.05) ADG, ADFI, and G:F compared with PC barrows. Overall (d 0 to 125), IC barrows had improved (P < 0.05) ADG and G:F and lower ADFI than PC barrows. The inclusion of 30% DDGS decreased (P < 0.05) G:F. Carcass yield was lower (P < 0.05) for IC than PC barrows. Pigs fed 30% DDGS throughout had decreased (P < 0.05) carcass yield; however, withdrawing DDGS from the diet on d 74 was effective at fully recovering the yield loss. Carcass fat iodine values (IV) were consistently higher (P < 0.05) regardless of fat depot or harvest time when 30% DDGS were included in the diet. Multiple two-way interactions (P < 0.05) were detected between castration method, DDGS,depot, and time. Interactions were a result of fatty acid profiles changing more rapidly in backfat and belly fat than in jowl fat from d 107 to 125 and more dramatically in IC than PC barrows in the same period. This improvement from d 107 to 125 could be caused by the dilution of unsaturated fatty acids, specifically C18:2 and C18:3, due to rapid deposition of fat from de novo synthesis in IC barrows.
    Journal of Animal Science 03/2014; 92(5). DOI:10.2527/jas.2013-6910 · 1.92 Impact Factor
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    ABSTRACT: Five experiments were conducted to evaluate replacing fish meal, meat and bone meal, and poultry by-product meal with crystalline AA for 7- to 12-kg pigs. In all experiments, pigs (PIC TR4 × 1050) were fed a common diet for 3 d postweaning, treatment diets for 14 d (d 0 to 14), and, again, a common diets for 14 d (d 14 to 28). Treatment diets were corn-soybean meal-based and formulated to contain 1.30% standardized ileal digestible (SID) Lys. Experiment 1 evaluated replacing dietary fish meal with crystalline AA. For the 6 treatments, crystalline Lys, Met, Thr, Trp, Ile, Val, Gln, and Gly all increased to maintain minimum AA ratios as fish meal decreased (4.50, 3.60, 2.70, 1.80, 0.90 to 0.00%). There was no difference in ADG, ADFI, or G:F among treatments, validating a low-CP, AA-fortified diet for subsequent experiments. Experiment 2 evaluated deleting crystalline AA from a low-CP, AA-fortified diet with 6 treatments: (1) a positive control (PC) similar to the diet validated in Exp. 1, (2) PC with L-Ile deleted, (3) PC with L-Trp deleted, (4) PC with L-Val deleted, (5) PC with L-Gln and L-Gly deleted, and (6) PC with L-Ile, L-Trp, L-Val, L-Gln, and L-Gly deleted (NC). Pigs fed the PC or Ile deleted diet had improved (P < 0.05) ADG and ADFI during d 0 to 14 compared with pigs fed diets with L-Trp or L-Val deleted or NC. Experiment 3 evaluated 6 treatments with total Lys:CP of 6.79, 6.92, 7.06, 7.20, 7.35, and 7.51%. Fish meal was adjusted as a source of dispensable N to achieve the target Lys:CP. There were no differences in growth performance among pigs fed different Lys:CP diets. Experiment 4 evaluated increasing SID Val:Lys with Val at 57.4, 59.9, 62.3, 64.7, 67.2, and 69.6% of Lys. Average daily gain and ADFI increased (quadratic, P < 0.01) and G:F improved (linear, P = 0.02) during 0 to 14 as Val:Lys increased from 57.4 to 64.7%. Experiment 5 was a 2 × 3 factorial arrangement of treatments with main effects of low or high level of crystalline AA and 3 animal protein sources (fish meal, meat and bone meal, or poultry by-product meal). Low- and high-crystalline AA diets contained 4.5 or 1% fish meal, 6 or 1.2% meat and bone meal, and 6 or 1% poultry by-product meal, respectively. No AA × protein source interactions were observed. From d 0 to 14, no differences in growth performance among protein sources was found, whereas increasing crystalline AA improved (P = 0.04) ADG. In conclusion, crystalline AA can replace fish meal, meat and bone meal, and poultry by-product meal when balanced for SID AA ratios of Met and Cys:Lys (58%), Thr:Lys (62%), Trp:Lys (16.5%), Val:Lys (65%), and Ile:Lys (52%).
    Journal of Animal Science 03/2014; 92(4). DOI:10.2527/jas.2013-6322 · 1.92 Impact Factor

Publication Stats

2k Citations
260.26 Total Impact Points

Institutions

  • 1994–2015
    • Kansas State University
      • • Department of Diagnostic Medicine/Pathobiology
      • • Department of Animal Sciences and Industry
      Манхэттен, Kansas, United States
  • 2003
    • Oklahoma State University - Stillwater
      • Department of Animal Science
      Stillwater, OK, United States