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1.
Crossbred barrows and gilts (n = 168) were used to test the effects of supplemental Mn during the growing-finishing period on performance, pork carcass characteristics, and pork quality during 7 d of retail display. Pigs were blocked by BW and allotted within blocks to pens (5 pigs/pen in blocks 1, 2, 5, and 6, and 4 pigs/pen in blocks 3 and 4). A total of 36 pens was randomly assigned to 1 of 6 dietary treatments, where the basal diets were formulated with (PC) or without (NC) Mn in the mineral premix, and supplemented with 0 or 350 ppm (as-fed basis) of Mn from MnSO4 or a Mn-AA complex (AvMn). Pigs were slaughtered at a commercial pork packing plant when the lightest block of pigs averaged 113.6 kg. During fabrication, boneless pork loins were collected and transported to Oklahoma State University, where 2.5-cm-thick LM chops were packaged in a modified atmosphere (80% O2 and 20% CO2) and subsequently placed in display cases (2 to 4 degrees C) under continuous fluorescent lighting (1,600 lx) for 7 d. Pig performance was not (P > or = 0.44) affected by supplemental Mn; however, during the grower-II phase, pigs fed the basal diets including Mn consumed less (P < 0.02) feed and tended to be more efficient (P < 0.09) than pigs fed the basal diets devoid of Mn. Throughout the entire feeding trial, neither dietary nor supplemental Mn altered (P > or = 0.22) ADG, ADFI, or G:F. Chops from pigs fed the diets supplemented with MnSO4 received greater (P < or = 0.05) lean color scores and had a redder (greater a* and hue angle values), more vivid color than chops from pigs fed the diets supplemented with AvMn. Additionally, LM chops from pigs fed the PC diets supplemented with MnSO4 were darker (lower L* values; P < 0.05) than chops from pigs fed the NC diets or PC diets supplemented with 0 or 350 ppm of AvMn. Even though discoloration scores were similar during the first 4 d of display, chops from pigs fed the PC diets supplemented with MnSO4 were less (P < 0.05) discolored on d 6 and 7 of retail display than chops from pigs fed the PC or NC diets and diets supplemented with AvMn (dietary treatment x display time, P = 0.04). Results of this study indicate that feeding an additional 350 ppm of Mn from MnSO4 above the maintenance requirements of growing-finishing pigs does not beneficially affect live pig performance but may improve pork color and delay discoloration of pork during retail display.  相似文献   

2.
Crossbred pigs, heterozygous for the halothane gene, were used to determine the effects of long-term dietary supplementation of magnesium mica (MM) and short-duration transportation stress on performance, stress response, postmortem metabolism, and pork quality. Pigs were blocked by weight, penned in groups (six pigs per pen), and pens (three pens per diet) were assigned randomly either to a control corn-soybean meal diet or the control diet supplemented with 2.5% MM (as-fed basis; supplemented at the expense of corn). Diets were fed during the early-finisher (0.95% lysine, as-fed basis; 43.7 to 68 kg) and late-finisher (0.85% lysine, as-fed basis; 68 to 103 kg) periods. At the conclusion of the 71-d feeding trial, 12 pigs from each dietary treatment were selected randomly and subjected either to no stress (NS) or 3 h of transportation stress (TS). Dietary MM had no effect (P > or = 0.40) on ADG or ADFI; however, G:F was improved (P < 0.05) during the early-finisher period when pigs were fed MM-supplemented diets. Plasma glucose concentrations were increased in TS pigs fed the control diet, but transportation did not affect plasma glucose in pigs fed 2.5% MM (diet x transportation stress; P = 0.02). Dietary MM did not affect blood lactate, cortisol, insulin, NEFA, Ca, or Mg concentrations in response to TS (diet x transportation stress; P > or = 0.13); however, circulating lactate, cortisol, and glucose concentrations increased in TS pigs (transportation stress x time; P < 0.01). The LM from TS pigs fed MM had higher initial (0-min) and 45-min pH values than the LM from NS pigs fed the control diet (diet x transportation stress x time; P = 0.07). Lactic acid concentration and glycolytic potential were greater in the LM of TS pigs fed MM than TS pigs fed control diets (diet x transportation stress; P < or = 0.01). Although some trends were identified, neither MM (P > or = 0.15) nor TS (P > or = 0.11) altered the color or water-holding capacity of the LM and semimembranosus. The transportation model elicited the expected changes in endocrine and blood metabolites, but dietary MM did not alter the stress response in pigs. Conversely, although pork quality traits were not improved by dietary MM, delaying postmortem glycolysis and elevating 0- and 45-min muscle pH by feeding finishing diets fortified with MM may benefit the pork industry by decreasing the incidence of PSE pork in pigs subjected to short-duration, routine stressors.  相似文献   

3.
Crossbred pigs (n = 185) were used to test the effects of dietary Fe supplementation on performance and carcass characteristics of growing-finishing swine. Pigs were blocked by BW, allotted to pens (5 to 6 pigs/pen), and pens (5 pens/block) were allotted randomly to either negative control (NC) corn-soybean meal grower and finisher diets devoid of Fe in the mineral premix, positive control (PC) corn-soybean meal grower and finisher diets with Fe included in the mineral premix, or the PC diets supplemented with 50, 100, or 150 ppm Fe from Availa-Fe (an Fe-AA complex). When the lightest block averaged 118.2 kg, the pigs were slaughtered, and bone-in pork loins were collected during fabrication for pork quality data. During the grower-I phase, there was a tendency for supplemental Fe to reduce ADG linearly (P = 0.10), whereas in the grower-II phase, supplemental Fe tended to increase ADG linearly (P = 0.10). Even though pigs fed NC had greater G:F during the finisher-I phase (P < 0.05) and across the entire trial (P = 0.07), live performance did not (P > or = 0.13) differ among dietary treatments. There were linear increases in 10th-rib fat depth (P = 0.08) and calculated fat-free lean yield (P = 0.06); otherwise, dietary Fe did not (P > 0.19) affect pork carcass muscling or fatness. Moreover, LM concentrations of total, heme, and nonheme Fe were similar (P > 0.23) among treatments. A randomly selected subset of loins from each treatment was further fabricated into 2.5-cm-thick LM chops, placed on styrofoam trays, overwrapped with polyvinyl chloride film, and placed in coffin-chest display cases (2.6 degrees C) under continuous fluorescent lighting (1,600 lx) for 7 d. During display, chops from NC-fed pigs and pigs fed the diets supplemented with 100 ppm Fe tended to have a more vivid (higher chroma value; P = 0.07), redder (higher a* value; P = 0.09) color than LM chops of pigs fed 50 ppm of supplemental Fe. Moreover, greater (P < 0.01) redness:yellowness ratios in chops from pigs supplemented with 100 ppm Fe indicated a more red color than chops from PC-fed pigs or pigs fed diets supplemented with 50 ppm Fe. In conclusion, however, increasing dietary Fe had no appreciable effects on performance, carcass, or LM characteristics, suggesting that current dietary Fe recommendations are sufficient for optimal growth performance, pork carcass composition, and pork quality.  相似文献   

4.
Two experiments were conducted to evaluate the effects of dietary Zn and Fe supplementation on mineral excretion, body composition, and mineral status of nursery pigs. In Exp. 1 (n = 24; 6.5 kg; 16 to 20 d of age) and 2 (n = 24; 7.2 kg; 19 to 21 d of age), littermate crossbred barrows were weaned and allotted randomly by BW, within litter, to dietary treatments and housed individually in stainless steel pens. In Exp. 1, Phases 1 (d 0 to 7) and 2 (d 7 to 14) diets (as-fed basis) were: 1) NC (negative control, no added Zn source); 2) ZnO (NC + 2,000 mg/kg as Zn oxide); and 3) ZnM (NC + 2,000 mg/kg as Zn Met). In Exp. 2, diets for each phase (Phase 1 = d 0 to 7; Phase 2 = d 7 to 21; Phase 3 = d 21 to 35) were the basal diet supplemented with 0, 25, 50, 100, and 150 mg/kg Fe (as-fed basis) as ferrous sulfate. Orts, feces, and urine were collected daily in Exp. 1; whereas pigs had a 4-d adjustment period followed by a 3-d total collection period (Period 1 = d 5 to 7; Period 2 = d 12 to 14; Period 3 = d 26 to 28) during each phase in Exp. 2. Blood samples were obtained from pigs on d 0, 7, and 14 in Exp. 1 and d 0, 7, 21, and 35 in Exp. 2 to determine hemoglobin (Hb), hematocrit (Hct), and plasma Cu, (PCu), Fe (PFe), and Zn (PZn). Pigs in Exp. 1 were killed at d 14 (mean BW = 8.7 kg) to determine whole-body, liver, and kidney mineral concentrations. There were no differences in growth performance in Exp. 1 or 2. In Exp. 1, pigs fed ZnO or ZnM diets had greater (P < 0.001) dietary Zn intake during the 14-d study and greater fecal Zn excretion during Phase 2 compared with pigs fed the NC diet. Pigs fed 2,000 mg/kg, regardless of Zn source, had greater (P < 0.010) PZn on d 7 and 14 than pigs fed the NC diet. Whole-body Zn, liver Fe and Zn, and kidney Cu concentrations were greater (P < 0.010), whereas kidney Fe and Zn concentrations were less (P < 0.010) in pigs fed pharmacological Zn diets than pigs fed the NC diet. In Exp. 2, dietary Fe supplementation tended to increase (linear, P = 0.075) dietary DMI, resulting in a linear increase (P < 0.050) in dietary Fe, Cu, Mg, Mn, P, and Zn intake. Subsequently, a linear increase (P < 0.010) in fecal Fe and Zn excretion was observed. Increasing dietary Fe resulted in a linear increase in Hb, Hct, and PFe on d 21 (P < 0.050) and 35 (P < 0.010). Results suggest that dietary Zn or Fe additions increase mineral status of nursery pigs. Once tissue mineral stores are loaded, dietary minerals in excess of the body's requirement are excreted.  相似文献   

5.
A total of 240 crossbred pigs were used in two experiments to determine the effect of feeding magnesium mica (MM) during the growing-finishing period on animal performance and pork carcass characteristics. All pigs were blocked by weight, and treatments were assigned randomly to pens (five pigs/pen) within blocks. In each experiment, eight pens were allotted randomly to one of three treatments: 1) a negative control corn-soybean meal starter, grower, and finisher diet devoid of supplemental magnesium; 2) the control diets supplemented with 1.25% MM; and 3) the control diets supplemented with 2.50% MM. In Exp. 1, pigs were slaughtered at the University of Arkansas Red Meat Abattoir, whereas pigs in Exp. 2 were transported to a commercial pork packing plant and slaughtered according to industry-accepted procedures. In both experiments, dietary supplementation of MM had no (P > .10) effect on ADG, ADFI, or gain:feed ratio at any phase during the growing-finishing period. In Exp. 1, MM supplementation had no (P > .10) effect on carcass fatness or muscling. Moreover, Japanese color scores were not (P > .10) affected by feeding pigs MM; however, American color scores increased linearly (P < .01) with increasing levels of MM in the diet. Although MM supplementation did not (P > .10) affect L* and b* values for the longissimus muscle (LM), there was a linear increase (P < .05) in LM a* and chroma values associated with increased MM levels in swine diets. In Exp. 2, carcasses from pigs fed 1.25% MM had less (P < .05) fat opposite the LM at the 10th rib than untreated controls and pigs fed 2.50% MM and higher (P < .10) percentages of muscle than carcasses of untreated controls. Moreover, the LM from pigs fed 1.25% MM was less (P < .05) red and less (P < .05) yellow than the LM from pigs fed the control or 2.50% MM-supplemented diets. Drip loss from the LM was unaffected (P > .10) by inclusion of MM in the diet. Results from this study confirm that inclusion of MM, an inexpensive, inorganic magnesium source, in diets of growing-finishing swine has beneficial effects on pork carcass cutability and quality with no deleterious effects on live animal performance.  相似文献   

6.
Two 28-d experiments were conducted to evaluate the efficacy of low dietary concentrations of Cu as Cu-proteinate compared with 250 ppm Cu as CuSO4 with growth performance, plasma Cu concentrations, and Cu balance of weanling swine as the criteria. In the production study (Exp. 1), 240 crossbred pigs that averaged 19.8 d of age and 6.31 kg BW initially were group-fed (two or three pigs per pen) the basal diets (Phase 1: d 0 to 14 and Phase 2: d 14 to 28) supplemented with 0 (control), 25, 50, 100, or 200 ppm Cu as Cu-proteinate, or 250 ppm Cu as CuSO4 (as-fed basis). The basal diets contained 16.5 ppm Cu supplied as CuSO4 before supplementation with Cu-proteinate or 250 ppm Cu as CuSO4. There were quadratic responses (P < or = 0.05) in ADFI and ADG for wk 1, Phases 1 and 2, and overall because ADFI was higher for pigs fed 25 or 50 ppm Cu as Cu-proteinate, and ADG increased with increasing Cu-proteinate up to 50 ppm Cu. The Cu-proteinate treatment groups combined had a higher (P < or = 0.05) Phase 2 and overall ADFI and ADG than the CuSO4 group. In the mineral balance study (Exp. 2), 20 crossbred barrows that averaged 35 d of age and 11.2 kg/BW initially were placed in individual metabolism pens with total urine and fecal grab sample collections on d 22 to 26. Treatments were the basal Phase 2 diet supplemented with 0, 50, or 100 ppm Cu as Cu-proteinate, or 250 ppm Cu as CuSO4 (as-fed basis). Treatments did not differ in growth performance criteria. There were linear increases (P < 0.001) in Cu absorption, retention, and excretion (milligrams per day) with increasing Cu-proteinate. Pigs fed 100 ppm Cu as Cu-proteinate absorbed and retained more Cu and excreted less Cu (mg/d, P < or = 0.003) than pigs fed 250 ppm Cu as CuSO4. Plasma Cu concentrations increased linearly (P = 0.06) with increasing Cu-proteinate. In conclusion, weanling pig growth performance was increased by 50 or 100 ppm Cu as Cu-proteinate in our production Exp. 1, but not in our balance Exp. 2, compared with 250 ppm Cu as CuSO4. However, 50 or 100 ppm Cu as Cu-proteinate increased Cu absorption and retention, and decreased Cu excretion 77 and 61%, respectively, compared with 250 ppm Cu as CuSO4.  相似文献   

7.
Four experiments were conducted to evaluate the effects of supplementing graded levels (0 to 100 ppm) of L-carnitine to the diet of weanling pigs on growth performance during a 34- to 38-d experimental period. A fifth experiment was conducted to determine the effects of addition of L-carnitine to diets with or without added soybean oil (SBO) on growth performance. In Exp. 1, 128 pigs (initial BW = 5.5 kg) were allotted to four dietary treatments (six pens per treatment of four to six pigs per pen). Dietary treatments were a control diet containing no added L-carnitine and the control diet with 25, 50, or 100 ppm of added L-carnitine. In Exp. 2, 3, and 4, pigs (4.8 to 5.6 kg of BW) were allotted to five dietary treatments consisting of either a control diet containing no added L-carnitine or the control diet with 25, 50, 75, or 100 ppm of added L-carnitine. All diets in Exp. 1 to 4 contained added soybean oil (4 to 6%). There were seven pens per treatment (four to five pigs per pen) in Exp. 2, whereas Exp. 3 and 4 had five and six pens/treatment (eight pigs per pen), respectively. In general, dietary carnitine additions had only minor effects on growth performance during Phases 1 and 3; however, dietary L-carnitine increased (linear [Exp. 1], quadratic [Exp. 2 to 4], P < 0.03) ADG and gain:feed (G:F) during Phase 2. The improvements in growth performance during Phase 2 were of great enough magnitude that carnitine addition tended to increase ADG (linear, P < 0.10) and improve G:F (quadratic, P < 0.02) for the entire 38-d period. In Exp. 5, 216 weanling pigs (5.8 kg of BW) were allotted (12 pens/treatment of four to five pigs per pen) to four dietary treatments. The four dietary treatments were arranged in a 2 x 2 factorial with main effects of added SBO (0 or 5%) and added L-carnitine (0 or 50 ppm). Pigs fed SBO tended (P < 0.07) to grow more slowly and consumed less feed compared with those not fed SBO, but G:F was improved (P < 0.02). The addition of L-carnitine did not affect (P > 0.10) ADG or ADFI; however, it improved (P < 0.03) G:F. Also, the increase in G:F associated with L-carnitine tended to be more pronounced for pigs fed SBO than those not fed SBO (carnitine x SBO, P < 0.10). These results suggest that the addition of 50 to 100 ppm of added L-carnitine to the diet improved growth performance of weanling pigs. In addition, supplemental L-carnitine tended to be more effective when SBO was provided in the diet.  相似文献   

8.
In each of two experiments, 924 pigs (4.99 kg BW; 16 to 18 d of age) were assigned to 1 of 42 pens based on BW and gender. Pens were allotted randomly to dietary copper (Cu) treatments that consisted of control (10 ppm Cu as cupric sulfate, CuSO4 x 5H2O) and supplemental dietary Cu concentrations of 15, 31, 62, or 125 ppm as cupric citrate (CuCit), or 62 (Exp. 2 only), 125 (Exp. 1 only), or 250 ppm as CuSO4. Live animal performance was determined at the end of the 45-d nursery phase in each experiment. On d 40 of Exp. 2, blood and fecal samples were collected from two randomly selected pigs per pen for evaluation of plasma and fecal Cu concentrations and fecal odor characteristics. In Exp. 1, ADG, ADFI, and G:F were increased (P < 0.05), relative to controls, when pigs were fed diets containing 250 ppm Cu as CuSO4. Pigs fed diets containing 125 ppm Cu as CuCit had increased (P < 0.05) ADG compared with pigs fed diets supplemented with 15 or 62 ppm Cu as CuCit. The ADG, ADFI, and G:F did not differ among pigs fed diets containing 125 and 250 ppm Cu as CuSO4 or 125 ppm Cu as CuCit. In Exp. 2, pigs fed diets containing 250 ppm Cu as CuSO4 had improved (P < 0.05) ADG, ADFI, and G:F compared with controls. In addition, ADG, ADFI, and G:F were similar when pigs were fed diets containing either 250 ppm Cu as CuSO4 or 125 ppm Cu as CuCit. Pigs fed diets containing 62 ppm Cu as CuSO4 or CuCit had similar ADG, ADFI, and G:F. Plasma Cu concentrations were not affected by dietary Cu source or concentration, but fecal Cu concentrations were increased (P < 0.05) as the dietary concentration of Cu increased. Pigs consuming diets supplemented with 125 ppm Cu as CuCit had fecal Cu concentrations that were lower (P < 0.05) than pigs consuming diets supplemented with 250 ppm Cu as CuSO4. Fecal Cu did not differ in pigs receiving diets supplemented with 62 ppm Cu as CuSO4 or CuCit. Odor characteristics of feces were not affected by Cu supplementation or source. These data indicate that 125 and 250 ppm Cu gave similar responses in growth, and that CuCit and CuSO4 were equally effective at stimulating growth and improving G:F in weanling pigs. Fecal Cu excretion was decreased when 125 ppm Cu as CuCit was fed compared with 250 ppm Cu as CuSO4. Therefore, 125 ppm of dietary Cu, regardless of source, may provide an effective environmental alternative to 250 ppm Cu as CuSO4 in weanling pigs.  相似文献   

9.
Five experiments were conducted to test the effects of various dietary humic substances (HS; HS1, 2, 3, and 4, each with different fulvic and humic acid contents) on pig growth, carcass characteristics, and ammonia emission from manure. In Exp. 1, 120 pigs were allotted to 3 dietary treatments without HS (control) or with HS1 at 0.5 and 1.0% (8 pens/treatment and 5 pigs/pen) and fed diets, based on a 5-phase feeding program, from weaning (d 21.3 +/- 0.3 of age) to 60 kg of BW. In Exp. 2 and 3, 384 pigs (192 for each experiment) were allotted to 3 dietary treatments without HS, with HS1, or with HS2 (0.5%) for Exp. 2 and without HS, or with HS3 or HS4 (0.5%) for Exp. 3 (8 pens/treatment and 8 pigs/pen in each experiment). Pigs were fed diets, based on a 6-phase feeding program, from weaning (25.4 +/-0.2 and 23.6 +/-0.3 d of age for Exp. 2 and 3, respectively) to 110 kg of BW. In Exp. 4, 96 pigs were weaned at 22.1 +/-0.2 d of age and allotted to 2 treatments without or with HS1 at 0.5% (6 pens/treatment and 8 pigs/pen), and in Exp. 5 96 pigs were weaned at 20.9 +/-0.3 d of age and allotted to 3 treatments without HS, or with HS3 or HS4 (0.5%; 4 pens/treatment and 8 pigs/pen). Pigs were fed the diets for at least 2 wk before they were moved to an environmental chamber to measure aerial ammonia and hydrogen sulfide for 48 h at 5-min intervals. In Exp. 1, pigs fed diets with HS1 at 0.5% had greater (P < 0.05) ADG during phase 3 and greater (P < 0.05) G:F during phases 3 and 5 than control pigs. In Exp. 2, pigs fed diets with HS1 or HS2 at 0.5% had greater (P < 0.05) ADG and G:F than control pigs during the entire feeding period, whereas in Exp. 3 HS3 or HS4 did not improve pig growth performance. Ammonia emission from manure was reduced by 18 or 16% when pigs were fed diets with HS1 (P = 0.067) or HS4 (P = 0.054), respectively. The results of this study indicate that the effects of dietary HS are variable but may improve growth performance of pigs and reduce ammonia emission from manure. Further research is needed to clarify these effects and the mechanisms by which HS may cause them.  相似文献   

10.
Three experiments were conducted to evaluate the effects of feeding dietary concentrations of organic Zn as a Zn-polysaccharide (Quali Tech Inc., Chaska, MN) or as a Zn-proteinate (Alltech Inc., Nicholasville, KY) on growth performance, plasma concentrations, and excretion in nursery pigs compared with pigs fed 2,000 ppm inorganic Zn as ZnO. Experiments 1 and 2 were growth experiments, and Exp. 3 was a balance experiment, and they used 306, 98, and 20 crossbred pigs, respectively. Initially, pigs averaged 17 d of age and 5.2 kg BW in Exp. 1 and 2, and 31 d of age and 11.2 kg BW in Exp. 3. The basal diets for Exp. 1, 2, and 3 contained 165 ppm supplemental Zn as ZnSO4 (as-fed basis), which was supplied from the premix. In Exp. 1, the Phase 1 (d 1 to 14) basal diet was supplemented with 0, 125, 250, 375, or 500 ppm Zn as Zn-polysaccharide (as-fed basis) or 2,000 ppm Zn as ZnO (as-fed basis). All pigs were then fed the same Phase 2 (d 15 to 28) and Phase 3 (d 29 to 42) diets. In Exp. 2, both the Phase 1 and 2 basal diets were supplemented with 0, 50, 100, 200, 400, or 800 ppm Zn as Zn-proteinate (as-fed basis) or 2,000 ppm Zn as ZnO (as-fed basis). For the 28-d Exp. 3, the Phase 2 basal diet was supplemented with 0, 200, or 400 ppm Zn as Zn-proteinate, or 2,000 ppm Zn as ZnO (as-fed basis). All diets were fed in meal form. In Exp. 1, 2, and 3, pigs were bled on d 14, 28, or 27, respectively, to determine plasma Zn and Cu concentrations. For all three experiments, there were no overall treatment differences in ADG, ADFI, or G:F (P = 0.15, 0.22, and 0.45, respectively). However, during wk 1 of Exp. 1, pigs fed 2,000 ppm Zn as ZnO had greater (P < or = 0.05) ADG and G:F than pigs fed the basal diet. In all experiments, pigs fed a diet containing 2,000 ppm Zn as ZnO had higher plasma Zn concentrations (P < 0.10) than pigs fed the basal diet. In Exp. 1 and 3, pigs fed 2,000 ppm Zn as ZnO had higher fecal Zn concentrations (P < 0.01) than pigs fed the other dietary Zn treatments. In conclusion, organic Zn either as a polysaccharide or a proteinate had no effect on growth performance at lower inclusion rates; however, feeding lower concentrations of organic Zn greatly decreased the amount of Zn excreted.  相似文献   

11.
We conducted two experiments to determine the effects of added dietary niacin on growth performance and meat quality in finishing pigs. Pigs were blocked by weight and assigned to one of six dietary treatments in both experiments. Dietary treatments consisted of a corn-soybean meal-based control diet (no added niacin) or the control diet with 13, 28, 55, 110, or 550 mg/kg of added niacin. In Exp. 1, pigs were housed at the Kansas State University research from with two pigs per pen (six pens per treatment per sex). In Exp. 2, pigs were housed with 26 pigs per pen (four pens per treatment per sex) in a commercial research barn. In Exp. 1, 144 pigs (initially 51.2 kg) were fed diets in two phases (d 0 to 25 and 25 to 62) that were formulated to 1.00 and 0.75% lysine, respectively. In Exp. 2, 1,248 pigs (initially 35.9 kg) were fed diets in four phases (d 0 to 28, 29 to 56, 57 to 84, and 85 to 117), with corresponding total lysine concentrations of 1.25, 1.10, 0.90, and 0.65% lysine, respectively. Added fat (6.0%) was included in the first three phases. In Exp. 1, average daily feed intake tended (quadratic, P < 0.07) to increase then return to values similar to control pigs as dietary niacin increased. Longissimus muscle (LM) 24-h pH (longissimus of pigs fed added niacin) tended to increase (control vs niacin, P < 0.06) for pigs fed added niacin. In the commercial facility (Exp. 2), increasing added niacin improved gain:feed (quadratic, P < 0.01) and subjective color score, and ultimate pH (linear, P < 0.01). Added niacin also decreased (linear, P < 0.04) carcass shrink, L* values, and drip loss percentage. Results from these two studies show that 13 to 55 mg/kg added dietary niacin can be fed to pigs in a commercial environment to improve gain:feed. It also appears that pork quality, as measured by drip loss, pH, and color, may be improved by higher concentrations of added dietary niacin.  相似文献   

12.
Two trials were conducted to determine the replacement nutritive value of dried skim milk for growing-finishing pigs. In a three-phase feeding trial, 180 growing composite barrows (40.8 +/- 2.9 kg BW) were allotted to three dietary treatments. Each phase lasted 28 d. Treatment 1 comprised a basal corn-soybean meal diet supplemented with crystalline AA to contain true ileal digestible concentrations (as-fed basis) of 0.83, 0.66, and 0.52% Lys; 0.53, 0.45, and 0.40% Thr; and 0.51, 0.45, and 0.42% sulfur amino acids (SAA; Met + Cys) in Phases 1, 2, and 3, respectively. Treatments 2 and 3 were the basal diets with 5 and 10% (as-fed basis) dried skim milk added. The three diets at each phase were formulated to have the same quantities of DE, true ileal digestible Lys, Thr, Trp, SAA, Ca, and available P. Pigs were housed 10 per pen (six pens/treatment), allowed ad libitum access to feed, and slaughtered at 121.6 +/- 9.3 kg BW. No differences were detected between pigs fed the basal diet and the dried skim milk diets or between pigs fed the 5 and 10% dried skim milk diets, respectively, in 84-d ADG (P = 0.84 or P = 0.71), ADFI (P = 0.54 or P = 0.91), and G:F (P = 0.80 or P = 0.97), in hot carcass weight (P = 0.66 or P = 0.74), 45-min postmortem LM pH (P = 0.90 or P = 0.53), 10th-rib backfat thickness (P = 0.24 or P = 0.77), LM area (P = 0.13 or P = 0.63), weights of belly (P = 0.43 or P = 0.70), trimmed wholesale cuts (P = 0.18 to 0.85 or P = 0.06 to 0.53), and ham components (P = 0.25 to 0.98 or P = 0.32 to 0.63). In the N balance trial, four littermate pairs of finishing gilts (82.9 +/- 2.0 kg BW) were assigned within pair to the basal or the 10% dried skim milk (as-fed basis) finishing diet. Daily feed allowance was 2.6x maintenance DE requirement and was given in two equal meals. Total fecal collection from eight meals and a 96-h urine collection began on d 14 when gilts weighed 92.1 +/- 2.2 kg BW. No differences were found between dietary treatments in gilt's daily N intake (P = 0.33) and the daily output of urinary urea (P = 0.88), urinary N (P = 0.97), fecal N (P = 0.69), and total manure (P = 0.62), as well as apparent total-tract N digestibility (P = 0.84) and N retention (P = 0.84). It is concluded that growing-finishing pigs fed diets containing 10% dried skim milk would have growth performance, carcass traits, and N digestibility and use similar to those fed typical corn-soybean meal diets.  相似文献   

13.
Two experiments were conducted to determine the effects of dietary B on the production of cytokines following an endotoxin challenge. In both experiments, pigs were obtained from litters generated from sows fed low-B (control) or B-supplemented (5 mg/ kg, as-fed basis) diets. In Exp. 1 and 2, 28 and 35 pigs, respectively (21 d old), remained with their littermates throughout a 49-d nursery phase and were fed either a control or B-supplemented diet. In Exp. 1, 12 pigs per treatment were moved to individual pens at the completion of the nursery phase and fed their respective experimental diet. On d 99 of the study, pigs were injected with 150 microg of phytohemagglutinin (PHA) to evaluate a local inflammatory response. Pigs receiving the B-supplemented diet had a decreased (P < 0.01) inflammatory response following PHA injection. Peripheral blood monocytes were isolated from six pigs per treatment on d 103 and cultured in the presence of lipopolysaccharide (LPS) to determine the effect of dietary B on tumor necrosis factor-alpha (TNF-alpha) production from monocytes. Isolated monocytes from pigs that received the B-supplemented diet had a numerically greater (P = 0.23) production of TNF-alpha. In Exp. 2, pigs were group housed with their littermates following the nursery phase for 43 d, after which 10 pigs per treatment were moved to individual pens. In Exp. 1 and 2, pigs were assigned randomly within dietary treatment to receive either an i.m. injection of saline or LPS on d 117 and d 109, respectively. The dose of LPS in Exp. 1 and 2 was 100 and 25 microg of LPS/kg of BW, respectively. In Exp. 1, serum TNF-alpha was increased (P < 0.01) at 2 h and tended to be increased (P < 0.11) at 6 and 24 h after injection by dietary B; however, only numerical trends existed for a B-induced increase in TNF-alpha in Exp. 2. Serum interferon-gamma (IFN-gamma) was increased (P < 0.01) at 6 h and tended to be increased (P < 0.08) at 24 h after injection in Exp. 1. In Exp. 2, dietary B also numerically increased IFN-alpha. These data indicate that dietary B supplementation increased the production of cytokines following a stress, which indicates a role of B in the immune system; however, these data do not explain the reduction in localized inflammation following an antigen challenge in pigs.  相似文献   

14.
Two experiments were conducted to determine the efficacy of mannan oligosaccharides (MOS) fed at two levels of Cu on growth and feed efficiency of weanling and growing-finishing pigs, as well as the effect on the immunocompetence of weanling pigs. In Exp. 1, 216 barrows (6 kg of BW and 18 d of age) were penned in groups of six (9 pens/treatment). Dietary treatments were arranged as a 2 x 2 factorial consisting of two levels of Cu (basal level or 175 ppm supplemental Cu) with and without MOS (0.2%). Diets were fed from d 0 to 38 after weaning. Blood samples were obtained to determine lymphocyte proliferation in vitro. From d 0 to 10, ADG, ADFI, and gain:feed (G:F) increased when MOS was added to diets containing the basal level of Cu, but decreased when MOS was added to diets containing 175 ppm supplemental Cu (interaction, P < 0.01, P < 0.10, and P < 0.05, respectively). Pigs fed diets containing 175 ppm Cu from d 10 to 24 and d 24 to 38 had greater (P < 0.05) ADG and ADFI than those fed the basal level of Cu regardless of MOS addition. Pigs fed diets containing MOS from d 24 to 38 had greater ADG (P < 0.05) and G:F (P < 0.10) than those fed diets devoid of MOS. Lymphocyte proliferation was not altered by dietary treatment. In Exp. 2, 144 pigs were divided into six pigs/pen (six pens/treatment). Dietary treatments were fed throughout the starter (20 to 32 kg BW), grower (32 to 68 kg BW), and finisher (68 to 106 kg BW) phases. Diets consisted of two levels of Cu (basal level or basal diet + 175 ppm in starter and grower diets and 125 ppm in finisher diets) with and without MOS (0.2% in starter, 0.1% in grower, and 0.05% in finisher). Pigs fed supplemental Cu had greater (P < 0.05) ADG and G:F during the starter and grower phases compared to pigs fed the basal level of Cu. During the finisher phase, ADG increased when pigs were fed MOS in diets containing the basal level of Cu, but decreased when MOS was added to diets supplemented with 125 ppm Cu (interaction, P < 0.05). Results from this study indicate the response of weanling pigs fed MOS in phase 1 varied with level of dietary Cu. However, in phase 2 and phase 3, diets containing either MOS or 175 ppm Cu resulted in improved performance. Pharmacological Cu addition improved gain and efficiency during the starter and grower phases in growing-finishing pigs, while ADG response to the addition of MOS during the finisher phase seems to be dependent upon the level of Cu supplementation.  相似文献   

15.
Four experiments were conducted to investigate the feeding value of South Dakota-grown field peas (Pisum sativum L.) for growing pigs. In Exp. 1, 96 pigs (initial BW = 22 +/- 3.35 kg) were allotted to four treatment groups (four pigs per pen, six replicate pens per treatment) and fed growing (0.95% Lys) and finishing (0.68% Lys) diets containing 0, 12, 24, or 36% field peas (as-fed basis). There were no differences among the treatment groups in ADG, ADFI, or G:F. Likewise, there were no differences in backfat thickness or lean meat percent among treatment groups, but pigs fed diets containing 12, 24, or 36% field peas had greater (P < 0.05) loin depths than pigs fed the control diet. In Exp. 2, 120 pigs (initial BW = 7.8 +/- 1.04 kg) were allotted to four treatment groups 2 wk after weaning. Pigs were then fed diets containing 0, 6, 12, or 18% field peas (as-fed basis) during the following 4 wk. There were five pigs per pen and six replicate pens per treatment. Results of the experiment showed no differences in ADG, ADFI, or G:F among treatment groups. In Exp. 3, apparent (AID) and standardized (SID) ileal digestibility coefficients of CP and AA in field peas and soybean meal were measured using six individually penned growing pigs (initial BW = 36.5 +/- 2.1 kg) arranged in a repeated 3 x 3 Latin square design. The AID for Met, Trp, Cys, and Ser, and the SID for Met, Trp, and Cys were lower (P < 0.05) in field peas than in soybean meal; but for CP and all other AA, no differences in AID or SID were observed between the two feed ingredients. Experiment 4 was an energy balance experiment conducted to measure the DE and ME concentrations in field peas and corn. Six growing pigs (initial BW = 85.5 +/- 6.5 kg) were placed in metabolism cages and fed diets based on field peas or corn and arranged in a two-period switch-back design. The DE values for field peas and corn (3,864 and 3,879 kcal/kg DM, respectively) were similar, but the ME of corn was higher (P < 0.05) than the ME of field peas (3,825 vs. 3,741 kcal ME/kg DM). The results from the current experiments demonstrate that the nutrients in South Dakota-grown field peas are highly digestible by growing pigs. Therefore, such field peas may be included in diets for nursery pigs and growing-finishing pigs in amounts of at least 18 and 36%, respectively, without negatively affecting pig performance.  相似文献   

16.
A total of 252 crossbred pigs were used in two experiments to determine the effect of feeding hydrolyzed feather meal (FM) during the growing-finishing period on animal performance, carcass composition, and pork quality. All pigs were blocked by weight, and dietary treatments were assigned randomly to pens within blocks. In Exp. 1, 24 pens were randomly assigned to one of three dietary treatments: 1) control corn-soybean meal starter, grower, and finisher diets devoid of FM; 2) control diets formulated with 3% FM; and 3) control diets formulated with 6% FM. During the starter phase, there was a quadratic decrease in average daily gain (P < 0.06) and gain:feed (P < 0.01) with increasing FM, and during the grower-II phase, gain:feed increased linearly (P < 0.07) with increasing FM inclusion level. However, dietary FM had no effects (P > 0.10) on performance during the grower-I phase, finisher phase, or in the overall trial. Moreover, carcasses from pigs fed 3% FM had greater (P < 0.05) average backfat depth than carcasses of pigs fed 0 and 6% FM, but FM did not affect (P > 0.10) ham or carcass lean composition. In Exp. 2, 24 pens were randomly allotted to one of four dietary treatments: 1) positive control corn-soybean meal-based starter, grower, and finisher diets; 2) negative control corn-soybean meal- and wheat middlings-based starter, grower, and finisher diets; 3) negative control diets formulated with 3% FM; and 4) negative control diets formulated with 6% FM. Dietary FM had no effect (P > 0.10) on average daily gain, average daily feed intake, or gain:feed during any phase of the experiment. Ham weight decreased linearly (P < 0.04), whereas ham lean weight increased linearly (P < 0.09), with increasing levels of FM in the diet. Pork from pigs fed 3% FM tended (quadratic effect, P < 0.10) to receive higher Japanese color scores than pork from pigs fed either negative control or 6% FM diets. Moreover, pork color became lighter (P c 0.08), less red (P < 0.001), and less yellow (P < 0.003) as FM level was increased in swine diets. Results from these two experiments indicate that as much as 6% FM can be incorporated into isolysinic diets of growing-finishing pigs without adversely impacting animal performance, carcass composition, or pork quality.  相似文献   

17.
Three experiments were conducted to evaluate pet food-grade poultry by-product meal (PBM) as a replacement protein source for fish meal (FM), blood meal (BM), and spray-dried plasma protein (SDPP) in weanling pig diets. In the first study, 200 crossbred pigs (initial BW = 6.5 kg) were weaned (21 d) and randomly allotted to one of four dietary treatments, which included a control and three test diets where PBM was substituted for FM, blood products, or both. Experimental diets were fed during Phase I (d 0 to 5 postweaning) and Phase II (d 5 to 19), and a common Phase III diet was fed from d 19 to 26. Overall (d 0 to 26), there was no difference in performance of pigs fed PBM in place of the other ingredients. However, during Phase I, BW (P < 0.05), ADG (P < 0.02), and intake (P < 0.001) in pigs fed diets containing SDPP were greater than those fed diets with PBM. In Exp. 2, the performance of pigs (n = 100, initial BW = 6.5 kg) fed diets containing 20% PBM (as-fed basis, replacing SDPP, BM, FM, and a portion of the soybean meal) in all phases of the nursery diet was compared with a group fed conventional diets without PBM. There were no differences in overall performance (d 0 to 26); however, ADG (P < 0.10) and feed intake were higher (P < 0.01) for pigs fed the conventional diet than for pigs fed the 20% PBM diet during Phase I (d 0 to 5). Experiment 3 was a slope-ratio assay to determine the ability of PBM to replace SDPP. A total of 320 pigs (initial BW = 7.32 kg) was weaned (21 d) and allotted to five treatment groups in three trials in a blocked design with product (SDPP or PBM) as the first factor, and lysine level (1.08, 1.28, 1.49%; as-fed basis) as the second factor. Growth rate increased with increasing lysine (P < 0.05), regardless of the source. These results indicate that PBM can be used in nursery diets in place of blood meal and fish meal without affecting performance. Furthermore, although feeding PBM in Phase I diets was not equivalent to SDPP during the first week, there was no overall difference in performance at the end of the nursery phase.  相似文献   

18.
Crossbred pigs (n = 216) were used to test the interactive effect, if any, of ractopamine (RAC) and dietary fat source on the performance of finishing pigs, pork carcass characteristics, and quality of LM chops during 5 d of simulated retail display (2.6 degrees C and 1,600 lx warm-white fluorescent lighting). Pigs were blocked by BW and allotted randomly to pens (6 pigs/pen), and, after receiving a common diet devoid of RAC for 2 wk, pens within blocks were assigned randomly to 1 of 4 diets in a 2 x 2 factorial arrangement, with 5% fat [beef tallow (BT) vs. soybean oil (SBO)] and RAC (0 vs. 10 mg/kg). Diets were formulated to contain 3.1 g of lysine/Mcal of ME and 3.48 Mcal/kg of ME. Across the entire 35-d trial, pigs fed RAC had greater (P < 0.01) ADG and G:F, but RAC did not affect (P = 0.09) ADFI; however, performance was not affected (P >or= 0.07) by dietary fat source. Carcass weight, LM depth, and lean muscle yield were increased (P < 0.01), whereas fat depth was decreased (P = 0.01), in carcasses from RAC-fed pigs; however, carcass composition measures were similar (P >or= 0.27) between fat sources. Feeding 10 mg/kg of RAC reduced (P 相似文献   

19.
Crossbred barrows (n = 144; 80 kg) from four farrowing groups were phenotypically selected into fat (FAT) and lean (LEAN) pens using ultrasound. The difference in 10th-rib fat depth between the LEAN and FAT groups was > or =0.5 cm. Within a farrowing group, pigs were assigned to pens (five pigs per pen and eight pens per phenotype) to equalize pen weight and fat depth. Pigs were fed a corn-soybean meal diet containing 19% CP, 1.0% added animal/vegetable fat, and 1.1% lysine (as-fed basis). Half the pens received 10 ppm (as-fed basis) of ractopamine (RAC) during the 28-d finishing phase. At 7-d intervals, live weight and feed disappearance were recorded to calculate ADG, ADFI, and G:F, and 10th-rib fat depth and LM area were ultrasonically measured to calculate fat-free lean and fat and muscle accretion rates. During the first 7 d on feed, LEAN pigs fed RAC gained less (P < 0.05) than FAT pigs fed RAC or LEAN and FAT pigs fed the control diet (RAC x phenotype; P = 0.02); however, RAC did not (P > 0.25) affect ADG after the second, third, and fourth weeks, or over the entire 28-d feeding period. Although wk-2 and -3 ADG were higher (P < or = 0.03) in LEAN than in FAT pigs, phenotype did not (P = 0.08) affect overall ADG. Dietary RAC decreased (P < or = 0.05) ADFI over the 28-d feeding trial, as well as in wk 2, 3, and 4, but intake was not (P > 0.20) affected by phenotype. Neither RAC nor phenotype affected (P > 0.10) G:F after 7 d on trial; however, RAC improved (P < or = 0.04) wk-3, wk-4, and overall G:F. Lean pigs were more efficient (P < or = 0.05) in wk 2 and 3 and over the duration of the trial than FAT pigs. Ultrasound LM accretion (ULA) was not (P > or = 0.10) affected by RAC; however, LEAN pigs had greater (P < or = 0.02) ULA in wk 2 and 4 than FAT pigs. Although fat depth was lower (P < 0.01) in RAC-fed pigs than pigs fed the control diet, ultrasound fat accretion rate indicated that RAC-pigs deposited less (P = 0.04) fat only during wk 4. In addition, calculated fat-free lean (using ultrasound body fat, ULA, and BW) was increased (P < 0.05) in RAC pigs after 3 and 4 wk of supplementation. In conclusion, RAC enhanced the performance of finishing swine through decreased ADFI and increased G:F, whereas carcass lean was enhanced through decreases in carcass fat and increases in carcass muscling.  相似文献   

20.
Three experiments were conducted to evaluate the effect of feeding pharmacological concentrations of zinc (Zn), from organic and inorganic sources, on growth performance, plasma and tissue Zn accumulation, and Zn excretion of nursery pigs. Blood from all pigs was collected for plasma Zn determination on d 14 in Exp. 1, d 7 and 28 in Exp. 2, and d 15 in Exp. 3. In Exp. 1, 2, and 3, 90, 100, and 15 crossbred (GenetiPorc USA, LLC, Morris, MN) pigs were weaned at 24+/-0.5, 18, and 17 d of age (6.45, 5.47, and 5.3 kg avg initial BW), respectively, and allotted to dietary treatment based on initial weight, sex, and litter. A Phase 1 nursery diet was fed as crumbles from d 0 to 14 in Exp. 1, 2, and 3, and a Phase 2 nursery diet was fed as pellets from d 15 to 28 in Exp. 1 and 2. The Phase 1 and Phase 2 basal diets were supplemented with 100 ppm Zn as ZnSO4. Both dietary phases contained the same five dietary treatments: 150 ppm additional Zn as zinc oxide (ZnO), 500 ppm added Zn as ZnO, 500 ppm added Zn as a Zn-amino acid complex (Availa-Zn 100), 500 ppm added Zn as a Zn-polysaccharide complex (SQM-Zn), and 3,000 ppm added Zn as ZnO. Overall in Exp. 1, pigs fed 500 ppm added Zn as SQM-Zn or 3,000 ppm added Zn as ZnO had greater ADG (P < 0.05) than pigs fed 150 ppm, 500 ppm added Zn as ZnO, or 500 ppm added Zn as Availa-Zn 100 (0.44 and 0.46 kg/d vs 0.35, 0.38, and 0.33 kg/d respectively). Overall in Exp. 2, pigs fed 3,000 ppm added Zn as ZnO had greater (P < 0.05) ADG and ADFI than pigs fed any other dietary treatment. On d 14 of Exp. 1 and d 28 of Exp. 2, pigs fed 3,000 ppm added Zn as ZnO had higher (P < 0.05) plasma Zn concentrations than pigs on any other treatment. In Exp. 3, fecal, urinary, and liver Zn concentrations were greatest (P < 0.05) in pigs fed 3,000 ppm added Zn as ZnO. On d 10 to 15 of Exp. 3, pigs fed 3,000 ppm added Zn as ZnO had the most negative Zn balance (P < 0.05) compared with pigs fed the other four dietary Zn treatments. In conclusion, feeding 3,000 ppm added Zn as ZnO improves nursery pig performance; however, under certain nursery conditions the use of 500 ppm added Zn as SQM-Zn may also enhance performance. The major factor affecting nutrient excretion appears to be dietary concentration, independent of source.  相似文献   

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