S.S. Dritz

Kansas State University, Kansas, United States

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Publications (555)257.99 Total impact

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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; · 2.09 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;
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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.
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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.
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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;
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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;
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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;
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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; · 2.09 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; · 2.09 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; · 2.09 Impact Factor
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    ABSTRACT: Immune system activation begins a host of physiological responses. Infectious agents are recognized by monocytes and macrophages which in turn stimulate cytokine production. It is the hormone-like factors called cytokines that orchestrate the immune response. The classic responses observed with immune system activation and cytokine production include: anorexia, fever, lethargy, recruitment of other immune cells, and phagocytosis. While production of immune system components is known to require some amino acids, increases in amino acid requirements are more than offset by the associated decrease in protein accretion and increased muscle protein degradation that also accompanies immune system activation. However, the biggest impact of cytokine production is a decrease in feed intake. Therefore, as feed intake decreases, the energy needed to drive protein synthesis is also decreased. This suggests that diets should still be formulated on a similar calorie:lysine ratio as those formulated for non-immune challenged pigs. The evidence is sparse or equivocal for increasing nutrient requirements during an immune challenge. Nutritionists and swine producers should resist the pressure to alter the diet, limit feed, or add expensive feed additives during an immune challenge. While immune stimulation does not necessitate changes in diet formulation, when pigs are challenged with non-pathogenic diarrhea there are potential advantages on gut health with the increased use of crystalline amino acids rather than intact protein sources (i.e., soybean meal). This is because reducing crude protein decreases the quantity of fermentable protein entering the large intestine, which lowers post weaning diarrhea. It also lowers the requirement for expensive specialty protein sources or other protein sources such as soybean meal that present immunological challenges to the gut. The objective of this review is two-fold. The first is to discuss immunity by nutrition interactions, or lack thereof, and secondly, to review amino acid requirement estimates for nursery pigs.
    Journal of animal science and biotechnology. 02/2014; 5(1):12.
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    ABSTRACT: Three studies were conducted to compare the effects of 4 different porcine intestinal mucosa products (PEP2, PEP2+, Peptone 50, and PEP-NS; TechMix Inc., Stewart, MN) with select menhaden fish meal (SMFM) on nursery pig performance. These intestine-derived mucosal ingredients are byproducts of heparin production, with a similar amount of mucosal protein, but differ based on the carriers with which they are co-dried. Enzymatically processed vegetable protein is the carrier for PEP2 whereas PEP2+ is co-dried with enzymatically processed vegetable proteins and biomass from crystalline AA production. Peptone 50 uses vegetable protein as its carrier while PEP-NS is co-dried with byproducts of corn wet milling and biomass from crystalline AA production. In Exp. 1, 300 weanling pigs (PIC 327 × 1050; initially 5.4 kg and 19 d of age) were allotted to 1 of 5 dietary treatments with 12 replications and 5 pigs per pen. Diets consisted of a negative control (NC) containing no specialty protein sources, NC with 4, 8, or 12% PEP2 in phases 1 (d 0 to 11) and 2 (d 11 to 25), and a positive control containing 4% spray-dried animal plasma (SDAP) in phase 1 and 4% SMFM in phase 2. From d 0 to 11, pigs fed SDAP had greater (P < 0.05) ADG and G:F than pigs fed PEP2. From d 11 to 25, increasing PEP2 increased (quadratic; P < 0.01) ADG and G:F, with the greatest response observed at 4%. In Exp. 2, 960 weanling pigs (Newsham GPK35 × PIC 380; initially 5.6 kg, and 20 d of age) were allotted to 1 of 5 dietary treatments with 32 pigs per pen and 6 replications per treatment. Diets included a control with 4.5% SDAP in phase 1 (d 0 to 7) and no specialty protein sources in phase 2 (d 7 to 21) or the control diet with 6% of the following: SMFM, PEP2+, Peptone 50, or PEP-NS. From d 0 to 21, pigs fed diets containing SMFM, PEP2+, or PEP-NS had greater (P < 0.05) ADG than pigs fed the control or 6% Peptone 50. In Exp. 3, 180 nursery pigs (PIC 327 × 1050; initially 6.4 kg and 28 d of age) were allotted to 1 of 5 dietary treatments with 5 pigs per pen and 6 replications per treatment. Treatment diets were fed from d 7 to 21 postweaning. Treatments consisted of a NC, NC with 3, 6, 9, or 12% PEP-NS, or NC with 6% SMFM. Overall, pigs fed increasing PEP-NS had improved (quadratic; P < 0.01) ADG and G:F, with the greatest improvement observed in pigs fed 6% PEP-NS, similar to those fed 6% SMFM. These results suggest PEP2, PEP2+, and PEP-NS can effectively replace SMFM in nursery pig diets.
    Journal of Animal Science 02/2014; 92(2):783-92. · 2.09 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 01/2014; · 2.39 Impact Factor
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    ABSTRACT: A total of 288 mixed-sex pigs (PIC 327 × 1050; initially 68.9 kg BW) were used in a 67-d study to determine the effects of increasing medium-oil dried distillers grains with solubles (DDGS; 7.63% ether extract, 30.1% CP, 19.53% ADF, 36.47% NDF, and 4.53% ash; as-fed) on growth performance and carcass traits in finishing pigs. Treatments consisted of a corn-soybean meal control diet or the control diet with 15, 30, or 45% medium-oil DDGS. Diets were fed over 2 phases (69 to 100 and 100 to 126 kg) and were not balanced for energy. Diets were formulated to meet or exceed the AA, vitamin, and mineral requirements and contained constant SID lysine levels within phase. Increasing medium-oil DDGS decreased (linear, P < 0.02) ADG and G:F. Average daily gain decreased approximately 2.3% for every 15% added medium-oil DDGS, whereas G:F decreased approximately 1.3% with every 15% added DDGS. In addition, final BW, HCW, carcass yield, and loin-eye depth decreased (linear, P < 0.03), and jowl iodine value (IV) increased (linear, P < 0.001) with increasing medium-oil DDGS. Nutrient digestibility of the DDGS source was determined using pigs (initially 25.6 kg BW) that were fed either a corn-based basal diet (96.6% corn, 3.4% vitamins and minerals) or a DDGS diet, which was a 50:50 blend of the basal diet and medium-oil DDGS. There were 12 replications for each diet consisting of a 5-d adaptation period followed by 2 d of total fecal collection on a timed basis. Feces were analyzed for GE, DM, CP, crude fiber, NDF, ADF, and ether extract. On an as-fed basis, corn was analyzed to contain 3,871 and 3,515 kcal/kg GE and DE, respectively. Medium-oil DDGS was analyzed to contain 4,585 and 3,356 kcal/kg GE and DE, respectively (as-fed basis). Digestibility coefficients of the medium-oil DDGS were: DM, 70.3%; CP, 82.9%; ether extract, 61.4%; ADF, 77.4%; NDF, 67.5%; and crude fiber, 67.2%. Caloric efficiency (ADFI × kcal energy intake/kg BW gain) was not different when expressed on a DE or a calculated ME or NE basis, which suggests that the energy values derived from the nutrient balance study were accurate. In conclusion, increasing dietary inclusion of medium-oil DDGS decreased ADG, G:F, final BW, HCW, and carcass yield and increased jowl fat IV relative to those fed a corn-soybean meal-based diet.
    Journal of Animal Science 12/2013; · 2.09 Impact Factor
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    ABSTRACT: A total of 84 sows (PIC 1050) and their litters were used to determine the effects of supplementing maternal diet with vitamin D3 on sow and pig performance, serum 25(OH)D3, milk vitamin D3, neonatal bone mineralization, and neonatal tissue vitamin D3. After breeding, sows were randomly assigned to 1 of 3 dietary vitamin D3 treatments (1,500, 3,000, or 6,000 IU/kg of complete diets). Sows were bled on d 0 and 100 of gestation and at farrowing and weaning (d 21). Pig BW was recorded at birth and weaning, and serum was collected from 2 pigs/litter at birth on d 10 and at weaning. A total of 54 pigs (18/treatment) were euthanized at birth and necropsied to sample bones and tissues. Sow and suckling pig performance and neonatal bone ash and bone density did not differ among maternal vitamin D3 treatments; however, sow 25(OH)D3 and milk vitamin D3 increased (linear, P < 0.01) with increasing maternal vitamin D3 supplementation. Piglet serum 25(OH)D3 increased (quadratic, P < 0.03) with increased maternal vitamin D3. Neonatal kidney vitamin D3 tended (quadratic, P = 0.08) to decrease with increasing maternal vitamin D3, but liver vitamin D3 tended (linear, P = 0.09) to increase with increasing maternal vitamin D3. At weaning, a subsample of 180 pigs (PIC 327 × 1050) were used in a 3 × 2 split plot design for 35 d to determine the effects of maternal vitamin D3 and 2 levels of dietary vitamin D3 (1,800 or 18,000 IU/kg) from d 0 to 10 postweaning on nursery growth and serum 25(OH)D3. Overall (d 0 to 35), nursery ADG and G:F were not affected by either concentration of vitamin D3, but ADFI tended (quadratic, P < 0.06) to decrease with increasing maternal vitamin D3 as pigs from sows fed 3,000 IU had lower ADFI compared with pigs from sows fed 1,500 or 6,000 IU/kg. Nursery pig serum 25(OH)D3 increased with increasing maternal vitamin D3 (weaning) on d 0 (linear, P < 0.01), and maternal × diet interactions (P < 0.01) were observed on d 10 and 21 because pigs from sows fed 1,500 IU had greater increases in serum 25(OH)D3 when fed 18,000 IU compared with pigs from sows fed 3,000 IU. In conclusion, sow and pig serum 25(OH)D3, milk vitamin D3, and neonatal tissue vitamin D3 can be increased by increasing maternal vitamin D3, and nursery pig 25(OH)D3 can be increased by increasing dietary vitamin D3; however, sow and pig performance and neonatal bone mineralization was not influenced by increasing vitamin D3 dietary levels.
    Journal of Animal Science 12/2013; · 2.09 Impact Factor
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    ABSTRACT: A total of 264 pigs (initially 41.0 kg BW) were used in a 90-d study to determine the effects of lowering dietary fiber prior to market on pigs fed high dietary fiber [provided by wheat middlings (midds) and distillers dried grains with solubles (DDGS)] on growth performance, carcass characteristics, carcass fat quality, and intestinal weights of growing-finishing pigs. Pens of pigs were randomly allotted by initial BW and sex to 1 of 6 treatments with 6 replications per treatment and 7 or 8 pigs per pen. A positive control (corn-soybean meal-based) diet containing no DDGS or midds (9.3% NDF) and a negative control diet with 30% DDGS and 19% midds (19% NDF) were fed throughout the entire trial (d 0 to 90). The other 4 treatments were arranged in a 2 × 2 factorial with the main effects of length of fiber reduction (23 or 47 d prior to marketing) and fiber level fed during the reduction period (low or medium). Pigs on these treatments were fed the negative control prior to the reduction treatment. The medium-fiber diet contained 15% DDGS and 9.5% midds (14.2% NDF) with the low-fiber diet was the positive control diet. Increasing the feeding duration of the low-fiber diets lowered overall ADFI (linear, P = 0.03) and improved G:F (linear, P < 0.01). Lowering the fiber level for the last 23 d did not influence growth performance; however, lowering the fiber level improved carcass yield (P = 0.002), with a greater response (P < 0.001) when the low-fiber diet was fed for 23 d. Jowl fat iodine value (IV) decreased when the longer lower fiber diets were fed (linear, P < 0.01) and was lower (P < 0.001) for pigs fed the low-fiber diet during the fiber reduction period than pigs fed the medium-fiber diet during the same time period; however, increasing the time lower fiber diets were fed from 23 to 47 d further reduced (P < 0.01) jowl IV. Increasing the duration that the control diet was fed by increasing the reduction time from 23 to 47 d increased (P < 0.01) backfat depth. Reducing the fiber level decreased full large intestine weight (linear, P = 0.005) with a greater response (P = 0.04) when the low-fiber diet was fed during the reduction period instead of the medium-fiber diet. In summary, lowering the fiber level prior to marketing can improve G:F, carcass yield, carcass IV, and reduce large intestine weight; however, the optimal duration of the fiber reduction period depends on the targeted response criteria.
    Journal of Animal Science 12/2013; · 2.09 Impact Factor
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    ABSTRACT: Four experiments were conducted to investigate the effects of varying concentrations of supplemental vitamin D3 on pig growth, feed preference, serum 25(OH)D3, and bone mineralization of nursing and weanling pigs. In Exp. 1, 270 pigs (1.71 ± 0.01 kg BW) were administered 1 of 3 oral vitamin D3 dosages (none, 40,000, or 80,000 IU vitamin D3) on d 1 or 2 of age. Increasing oral vitamin D3 increased serum 25(OH)D3 on d 10 and 20 (quadratic, P < 0.01) and d 30 (linear, P < 0.01). No differences were observed in ADG prior to weaning, or for nursery ADG, ADFI, or G:F. Vitamin D3 concentration had no effect on bone ash concentration or bone histological traits evaluated on d 19 or 35. In Exp. 2, 398 barrows (initially 7 d of age) were used in a 2 × 2 split plot design to determine the influence of vitamin D3 before (none or 40,000 IU vitamin D3 in an oral dose) or after weaning (1,378 or 13,780 IU vitamin D3/kg in nursery diets from d 21 to 31 of age) in a 45-d trial. Prior to weaning (7 to 21 d of age), oral vitamin D3 dose did not influence growth but increased (P < 0.01) serum 25(OH)D3 at weaning (d 21) and tended (P = 0.08) to increase 25(OH)D3 on d 31. Increasing dietary vitamin D3 concentration from d 21 to 31 increased (P < 0.01) serum 25(OH)D3 on d 31. Neither the oral vitamin D3 dose nor nursery vitamin D3 supplements influenced nursery ADG, ADFI, or G:F. In Exp. 3, 864 pigs (initially 21 d of age) were allotted to 1 of 2 water solubilized vitamin D3 treatments (none or 16,516 IU/L vitamin D3 provided in the drinking water from d 0 to 10) in a 30-d study. Providing vitamin D3 increased serum 25(OH)D3 concentrations on d 10, 20, and 30; however, vitamin D3 supplementation did not affect overall (d 0 to 30) ADG, ADFI, or G:F. In Exp. 4, 72 pigs were used in a feed preference study consisting of 2 feed preference comparisons. Pigs did not differentiate diets containing either 1,378 or 13,780 IU vitamin D3/kg but consumed less (P < 0.01) of a diet containing 44,100 IU vitamin D3/kg compared with the diet containing 1,378 IU vitamin D3/kg. Overall, these studies demonstrate that supplementing vitamin D3 above basal concentrations used in these studies is effective at increasing circulating 25(OH)D3, but the supplement did not influence growth or bone mineralization. Also, concentrations of vitamin D3 of 44,100 IU/kg of the diet may negatively affect feed preference of nursery pigs.
    Journal of Animal Science 11/2013; · 2.09 Impact Factor
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    ABSTRACT: Samples of sorghum distillers dried grains with solubles (DDGS) were collected and analyzed to establish a nutrient database and evaluate the quality and consistency between and within 5 ethanol plants in Kansas and Texas. Each sample (n = 21) was analyzed for AA, DM, CP, crude fiber, crude fat, ash, NDF, ADF, trace minerals, and starch. Mean values (DM basis) were: 0.88% Lys, 10.49% crude fat, 34.21% CP, and 4,722 kcal/kg GE. The standard deviations among sorghum DDGS plants were similar to those within plants for most nutrients. Results of these analyses were used to formulate diets for 2 nursery trials. The 2 experiments were conducted to determine the effects of adding sorghum DDGS (29.0% CP; 7.2% crude fat) added to corn- or sorghum-based diets on nursery pig growth performance. In Exp. 1, 360 nursery barrows (6.8 kg and 26 d of age) were used in a 34-d study. Pigs were allotted to 1 of 8 dietary treatments with 5 pigs per pen and 9 pens per treatment. Treatments were arranged in a 2 × 4 factorial with main effects of grain source (corn vs. sorghum) and sorghum DDGS (0, 15, 30, or 45%). Diets were formulated to 1.30% and 1.25% standardized ileal digestible (SID) Lys in phases 1 and 2, respectively, but were not balanced for energy. Overall, there were no differences among pigs fed sorghum- or corn-based diets for ADG and ADFI; however, as sorghum DDGS increased from 0 to 45% of the diet, ADG decreased (linear, P < 0.01). There was a DDGS × grain source interaction (linear, P < 0.04) observed for G:F. In corn-based diets, pigs fed increasing sorghum DDGS had relatively similar G:F. However, in pigs fed sorghum-based diets, G:F was best for those fed 0% DDGS, but was decreased in pigs fed 15, 30 or 45% sorghum DDGS. In Exp. 2, 180 nursery pigs (10.7 kg and 38 d of age) were used in a 21-d study with 6 pigs per pen and 5 pens per treatment. Treatments were arranged in a 2 × 3 factorial with main effects of grain source (corn vs. sorghum) and DDGS (0 vs. 30% corn or sorghum DDGS). Diets were formulated to 1.27% SID Lys and were not balanced for energy. Overall, there were no differences in ADG among pigs fed sorghum-or corn-based diets as well as no differences among pigs fed sorghum or corn DDGS. Pigs fed diets with 30% DDGS gained less (P < 0.03) than pigs fed basal diets. These results indicate sorghum can be a suitable replacement for corn in nursery pig diets, but increasing sorghum DDGS decreased ADG.
    Journal of Animal Science 10/2013; · 2.09 Impact Factor
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    ABSTRACT: Two experiments (384 pigs; C22 × L326, PIC) were conducted to determine the interactive effect of dietary L-carnitine and ractopamine HCl (RAC) on pigs' metabolic response to handling. Experiments were arranged as split-split plots with handling as the main plot and diets as subplots (4 pens per treatment). Dietary L-carnitine (0 or 50 mg/kg) was fed from 36.0 kg to the end of the experiments (118 kg), and RAC (0 or 20 mg/kg) was fed the last 4 wk of each experiment. At the end of each experiment, 4 pigs per pen were assigned to 1 of 2 handling treatments. Gently handled pigs were moved at a moderate walking pace 3 times through a 50-m course and up and down a 15° loading ramp. Aggressively handled pigs were moved as fast as possible 3 times through the same course, but up and down a 30° ramp, and shocked 3 times with an electrical prod. Blood was collected immediately before and after handling in Exp. 1 and immediately after and 1 h after handling in Exp. 2. Feeding RAC increased (P < 0.01) ADG and G:F; but there was no effect of L-carnitine on growth performance. In Exp. 1 and 2, aggressive handling increased (P < 0.01) blood lactate dehydrogenase (LDH), lactate, cortisol, and rectal temperature and decreased blood pH. In Exp. 1, there was a RAC × handling interaction (P < 0.06) for the difference in pre- and post-handling blood pH and rectal temperature. Aggressively handled pigs fed RAC had decreased blood pH and increased rectal temperature compared with gently handled pigs demonstrating the validity of the handling model. Pigs fed RAC had increased (P < 0.01) LDH compared with pigs not fed RAC. Pigs fed L-carnitine had increased (P < 0.03) lactate compared with pigs not fed L-carnitine. In Exp. 2, pigs fed RAC had lower (P < 0.02) blood pH immediately after handling, but pH returned to control levels by 1 h post-handling. Lactate, LDH, cortisol, and rectal temperature changes from immediately post-handling to 1 h post-handling were not different between pigs fed L-carnitine and those fed RAC, indicating that L-carnitine did not decrease recovery time of pigs subjected to aggressive handling. These results suggest that pigs fed 20 mg/kg of RAC are more susceptible to stress when handled aggressively compared with pigs not fed RAC. Dietary L-carnitine fed in combination with RAC did not alleviate the effects of stress. This research emphasizes the importance of using proper animal handling techniques when marketing finishing pigs fed RAC.
    Journal of Animal Science 07/2013; · 2.09 Impact Factor
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    ABSTRACT: Two studies were conducted to determine the effects of diet form (meal vs. pellet) and feeder design (conventional dry vs. wet/dry) on finisher pig performance. Experiments were arranged as 2 × 2 factorials with 11 replications per treatment and 26 to 29 pigs per pen. In Exp. 1, pigs (n = 1,290; initial BW 46.8 kg) were used in a 91-d study. Pelleted diets averaged approximately 35% fines throughout the study. Overall, pigs fed pelleted diets or via wet/dry feeders had greater (P < 0.07 and 0.001, respectively) ADG than pigs fed meal diets or fed with a dry feeder. Diet form × feeder interactions (P < 0.02) were observed for G:F. Pigs fed either meal or pelleted diets via a wet/dry feeder had similar G:F, but pigs fed pelleted diets in dry feeders had poorer G:F than pigs with meal diets in dry feeders. In Exp. 2, pigs (n = 1,146; initial BW 38.2 kg) were used in a 104-d study. From d 0 to 28, a diet form × feeder design interaction (P < 0.01) was observed for ADG, which was due to decreased ADG in pigs fed pelleted diets from a conventional dry feeder compared with pigs fed meal diets from the same feeder type whereas there was no difference in wet/dry feeders based on diet form. Pigs fed pelleted diets had poorer (P < 0.01) G:F than pigs fed meal diets. This result appeared to be due to poor pellet quality (39.6% fines). From d 42 to 86, pellet quality improved (4.4% fines) and a diet form × feeder interaction was observed for ADG in which pigs fed meal diets in a dry feeder had decreased (P < 0.05) ADG than pigs fed pelleted diets in dry feeders or pigs presented either diet in wet/dry feeders. Pigs fed pelleted diets had improved (P < 0.001) G:F. Pigs fed via wet/dry feeders had increased (P < 0.03) ADFI and G:F compared with pigs fed via dry feeders. Overall, pigs fed with wet/dry feeders had increased (P < 0.02) ADG and ADFI and poorer G:F than pigs with dry feeders whereas pigs given pelleted diets had improved (P = 0.05) G:F compared with pigs presented meal diets. These studies found that pigs fed from wet/dry feeders had increased ADG and ADFI compared with pigs fed via dry feeders regardless of diet form. Additionally, pellet quality appeared to influence responses because pigs fed high-quality pellets via dry feeders had better growth performance than pigs fed meal diets. Conversely, if pellet quality was poor, the feed efficiency benefits associated with pelleting were lost.
    Journal of Animal Science 07/2013; 91(7):3420-3428. · 2.09 Impact Factor

Publication Stats

1k Citations
257.99 Total Impact Points

Institutions

  • 1995–2014
    • Kansas State University
      • • College of Veterinary Medicine
      • • Department of Animal Sciences and Industry
      • • Department of Anatomy and Physiology
      Kansas, United States
  • 2009
    • University of Nebraska at Lincoln
      • Department of Animal Science
      Lincoln, NE, United States
  • 2003
    • Oklahoma State University - Stillwater
      • Department of Animal Science
      Stillwater, OK, United States