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1.
In four trials, steer calves were received in the feedlot, processed and fed diets supplemented with soybean meal (SBM), 1% urea (UR) or 1% urea plus sarsaponin (S) over a 28-d period. In trials 1 and 2, the feeding period was extended to approximately 62 d, in which steers were fed a common (SBM) diet the last 34 d. In trials 3 and 4, a SBM plus S diet treatment was included. During the first 28 d (four trial summary) daily gains of steers fed urea plus S (.74 kg) were intermediate to and significantly different from gains of steers fed SBM (.84 kg) or UR (.66 kg) diets. However, at the end of the 62-d feeding period (two trial summary) daily gains, feed intakes and feed efficiency did not differ (P greater than .05) among treatments. No significant improvements in performance were found in steers fed SBM diets supplemented with S. In swine trials, pigs were fed diets containing no additive, 63 mg S X kg-1, 55 mg chlortetracycline (C) X kg-1 or S plus C in a grower-finisher (GF) and grower (G) trial. In the GF trial, overall efficiency of feed conversion was improved (P less than .05) by feeding S or S plus C. In the G trial, daily gains and intakes were greatest for pigs fed S plus C and differed (P less than .1) from those of pigs fed S or C in the diet. Compared with feeding S or C alone, gain and intake of growing pigs were stimulated to a greater extent when S was fed in combination with C. Feeding S with or without C improved efficiency of feed conversion in finishing pigs.  相似文献   

2.
Three growth experiments were conducted to assess the effect of fumaric acid (FA) supplementation on the performance of pigs fed different types of diets. These 4-wk experiments involved 550 crossbred pigs weaned at 30 +/- 3 d of age. Pigs in Exp. 1 were fed either a simple corn-soybean meal (SBM) diet or a 75% corn-SBM, 25% dried skim milk (DSM) diet. Zero, 2, or 3% FA were added to the diets to create a 2 x 3 factorial arrangement of treatments. Supplementing diets with DSM improved gain (P less than .05) and gain/feed (P less than .001). Fumaric acid addition improved efficiency of feed utilization (P less than .01). Experiment 2 was conducted to evaluate the effect of protein source (casein or soy protein concentrate [SPC]) on the response to 3% FA. Sodium bicarbonate (BCB; 2.75%) was added to one diet containing casein and FA to negate the effect of FA on growth performance. Addition of FA improved gain and feed efficiency (P less than .05) during the first 2 wk.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

3.
Three experiments were conducted to determine the effect of receiving diets containing alfalfa meal and certain feed additives on performance of comingled feeder pigs transported 900 to 1,100 km. In Exp. 1, the inclusion of 9.4% dehydrated alfalfa meal in receiving diets for 2 wk resulted in no difference (P greater than .1) in gain or feed conversion from purchase to market compared with pigs fed a basal corn-soybean meal (CS) diet or a diet containing 20% ground whole oats (O). In Exp. 2, pigs fed receiving diets containing 10% dehydrated alfalfa meal had no improvement (P greater than .1) in gain (.60 vs .61 kg/d) or conversion (3.25 vs 3.17) compared with CS-fed pigs. In Exp. 3, pigs fed a receiving diet for 2 wk containing 10% mid-bloom alfalfa ate more (P less than .002) feed daily for 2 wk (.82 vs .76 kg) and overall (P less than .04; 1.92 vs 1.85 kg) and had an improved (P less than .03) daily gain from purchase to market (.61 vs .59 kg) compared with CS-fed pigs. In Exp. 2, pigs fed diets containing 44 mg/kg tylosin (T) gained similar to pigs fed no additive (O) and slower (P less than .01) than pigs fed 110 mg/kg chlortetracycline (CTC; .59, .60 and .63 kg/d), with no significant differences in feed to gain conversion (3.12, 3.23 and 3.18).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

4.
Growth and carcass traits of finishing swine fed amino acid-supplemented raw soybean (RSB) diets were examined. Experiments 1 and 2 were identical and included the following treatments: 1) corn-soybean meal (SBM), 2) corn-RSB (lysine equal to Diet 1), 3) Diet 2 + .15% L-lysine (LYS), 4) Diet 3 + .1% L-threonine (THR), 5) Diet 3 + .05% L-tryptophan (TRP), 6) Diet 3 + .15% DL-methionine (MET) and 7) Diet 3 + THR + TRP + MET equivalent to Diets 4 to 6. The unsupplemented corn-RSB diet reduced (P less than .05) gain, gain:feed, plasma urea N, loin eye area, and percentage of muscling compared with the corn-SBM diet. The addition of LYS or LYS + TRP generally improved these response variables, whereas the addition of LYS + THR or LYS + MET tended to reduce gain and gain:feed compared with the LYS addition alone. The LYS + THR + TRP + MET addition resulted in growth and carcass traits that were intermediate between those of pigs fed the corn-RSB and the corn-SBM diets but not different (P greater than .05) from either. Experiment 3 included Diets 1, 2 and 7 from Exp. 1 and 2, in addition to the following treatment: corn-RSB + LYS + THR + TRP. The LYS + THR + TRP addition improved (P less than .05) growth and carcass traits compared with the LYS + THR + TRP + MET addition.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

5.
Concurrent in vivo and in vitro studies were conducted to evaluate urea (U), soybean meal (SBM), ground soybeans (RAW), extruded soybeans (ES) or extruded soybeans plus urea (ES + U) as primary supplemental N sources in starter diets for Holstein steers. Three groups of 48 Holstein steers each were fed five different starter diets to 181 kg BW in three experimental periods over 2 yr. Average daily gains were similar (P greater than .05) for steers fed ES + U (1.12 kg), ES (1.08 kg) and SBM (1.09 kg) but lower (P less than .05) for those fed U (1.00 kg) or RAW (.97 kg) diets. Feed/gain was similar (P greater than .05) for ES-fed steers vs those fed other diets except U. From 181 to 477 kg, all steers were fed the same diet. Steers fed the RAW starter diet had the lowest (P less than .05) ADG for the entire period. The starter diets were used as substrates for ruminal microbial metabolism in eight dual-flow continuous culture fermenters. True OM digestion was higher and NDF and ADF digestion was lower (P less than .05) for the ES + U diet than for the ES diet. Dietary protein degradation was lowest (P less than .05) for the ES diet (64.4%). Total bacterial N flow was higher (P less than .05) with the ES + U, SBM and U diets than with the ES diet. Lysine flow was higher (P less than .05) for the ES + U diet than for all other diets except ES. Results of these experiments indicate that ES as a protected ruminal escape N source with or without added urea did not improve steer performance above that obtained from SBM in starter diets.  相似文献   

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

7.
Three feeding trials (278 pigs) and one balance trial (14 pigs) were conducted to evaluate acceptance and utilization of diets containing a dry-fat product containing 90% fat. The fat was a mixture of equal parts vegetable and animal fats. In Trial 1, 4-wk-old pigs fed diets with 5% dry-fat added had average daily gain (ADG), average daily feed intake (ADFI) and gain/feed (G/F) values equal to pigs fed the diet containing 4.5% liquid fat, the unprocessed equivalent to the dry-fat. Values for G/F with both diets were higher (P less than .05) than for pigs fed the unsupplemented control diet. In Trial 2, dry-fat and roasted soybeans were compared as sources of supplemental fat in diets for finishing pigs. Both were efficiently utilized, with no differences (P greater than .05) among diets. In Trial 3, diets with 0, 5 and 10% levels of added dry-fat were fed to pigs from 34 to 100 kg. Rates of gain were not affected, but ADFI decreased (P less than .05) and G/F increased (P less than .05) with increased fat level. Carcass measurements were not affected by dietary treatment, but iodine number of backfat increased (P less than .05) with dietary fat level. In Trial 4, values for grams of N absorbed and retained and megacalories of energy absorbed and metabolized did not differ (P greater than .05) between diets with 0 and 5% added dry-fat. These results show that the dry-fat product was efficiently utilized by growing and finishing pigs.  相似文献   

8.
One hundred fifty crossbred pigs (55 kg) were allotted by weight, sex and litter to a randomized complete-block design with five dietary treatments, six blocks per treatment and five pigs per pen with sex equalized across treatments. Corn-soybean meal-based diets (.65% lysine) with 0, .25 and .5 mg/kg cimaterol were fed, on an ad libitum basis, to pigs slaughtered at an average pen weight of 104 kg/pig. Drug withdrawal prior to slaughter was 1, 3 and 5 d for pigs fed cimaterol at .25 mg/kg and 1 d for those fed cimaterol at .5 mg/kg of diet. Dietary cimaterol level influenced (quadratic, P less than .01) average daily gain during the first 42 d on test; however, daily feed intake and feed conversion ratio were not affected (P greater than .1). Pigs fed .25 mg/kg cimaterol with a 1-d drug withdrawal had 6.8, 7.7 and 13.5% less 10th rib fat depth and 11.1, 6.1 and 13.3% less P2 fat depth than those subjected to either a 3- or 5-d drug withdrawal or those fed the 0 mg/kg cimaterol diet (control), respectively. Overall, pigs fed cimaterol had 7.9% larger longissimus muscle area and 2.6% more kilograms of muscle than pigs fed the control diet. Cimaterol fed at .5 mg/kg resulted in higher (P less than .05) Warner-Bratzler shear force values and altered the proportion of saturation in some long-chain fatty acids, although the total saturated:unsaturated fat ratio was not affected. Pigs fed no cimaterol had less thaw loss (P less than .05) than did those fed other treatments.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

9.
A total of 280 crossbred pigs weaned at 21 d of age and weighing approximately 6 kg were utilized in five replicates to evaluate pig growth responses when fed a basal diet or one of several dietary lipid sources during a 4-wk postweaning period. A basal corn-soybean meal-corn starch-dried whey diet was compared with diets supplemented at a 7.75% level with one of the following lipid sources: corn oil, coconut oil, soybean oil, medium-chain triglyceride (MCT) or an animal-vegetable blend. A sixth treatment evaluated a roasted soybean diet formulated to an energy:lysine level equivalent to that of the fat-supplemented diets. In Exp. II, 36 crossbred weanling barrows were used to determine apparent fat and N digestibilities when soybean oil, roasted soybean, coconut oil or the MCT-supplemented diets were fed. Although pigs fed coconut oil grew somewhat faster, fat inclusion generally did not increase pig growth rate or result in lowered feed intake during the initial weeks postweaning; during the latter portion of the starter phase the addition of dietary fat resulted in a higher growth rate but feed intake was unaffected, resulting in an overall improvement in feed-to-gain ratio (P less than .05) for all but the roasted soybean diet. Pigs fed coconut oil had higher serum triglyceride and lower serum urea concentrations than did pigs fed diets containing most other lipid sources. Pigs fed MCT and coconut oil diets had a higher (P less than .01) apparent fat digestibility during the initial 2 wk postweaning than pigs fed soybean oil or roasted soybean diets. Pigs fed MCT and roasted soybeans had poorest growth rates; apparent fat and N digestibilities were lowest (P less than .05) for the roasted soybean diet.  相似文献   

10.
Growth traits with starter and grower pigs and a digestion trial were conducted to compare the nutritional value of Quality Protein Maize (QPM), food corn and conventional feed corn. The QPM, food and feed corn contained .45, .31 and .29% lysine, respectively. The growth trials evaluated a QPM-soybean meal diet formulated on a lysine basis (.96% in starter and .7% in grower diets) and four diets arranged in a 2 (food corn vs feed corn) X 2 (low vs high soybean meal) factorial. Soybean meal was either added in the same amount as in the QPM diet or was added to provide the lysine content of the QPM diet. Performance was similar for pigs fed food corn and feed corn in both trials. The QPM diets resulted in greater performance than food and feed corn diets containing the same level of soybean meal supplementation; starter pigs were more (P less than .10) efficient and grower pigs had a higher (P less than .01) rate and efficiency of gain. However, performance of pigs fed the QPM diets was not equal to that of pigs fed isolysinic food and feed corn diets; growth rate was lower (P less than .05) in starter pigs and gain:feed was lower (P less than .05) in grower pigs. Diets in the digestion trial consisted of the corns plus 3.25% casein. Energy digestibility was similar for all diets. Ileal N and amino acid digestibilities were highest for QPM, intermediate for food corn and lowest for feed corn. In most instances, these differences were significant (P less than .05). Apparent biological value was highest (P less than .05) for QPM. These trials indicate that food corn and feed corn have similar nutritional value, and that starter and grower pigs can benefit from the higher protein quality of QPM.  相似文献   

11.
One hundred seventy-six crossbred weaned pigs (4 to 5 wk old) were used in two growth trials to determine the effect of excess arginine on pig growth and plasma amino acid levels. In the first 28-d growth trial, two lysine levels (1.03 and 1.26%) and three arginine levels (.94, 1.29 and 1.63%) were used in a nested treatment arrangement. Lysine supplementation improved daily gains (P less than .05), tended to improve feed efficiency (P less than .12) and caused a general reduction in plasma essential amino acid levels. Arginine had no effect on daily gain or feed intake, but pigs fed 1.03% lysine and 1.63% arginine had reduced gain/feed (P less than .05). Arginine did not affect gain/feed of pigs fed 1.26% lysine. Plasma lysine levels were reduced (P less than .06) by excess arginine in pigs fed 1.26% lysine, but not in pigs fed 1.03% lysine. The four treatments for the second 26-d growth trial consisted of three diets containing .92% lysine and either .72, 1.10 or 1.61% arginine and a positive lysine control (1.10% lysine, .72% arginine). Lysine was the limiting amino acid in the basal diet, but arginine had no effect on daily gain, daily feed intake, gain/feed or plasma lysine levels. Plasma threonine and methionine levels were reduced by excess arginine in both experiments, while the other plasma essential amino acid levels were not affected by dietary arginine. Conclusions are that large excesses of added arginine may affect lysine utilization, but pig performance was affected only when excess arginine was combined with a lysine deficiency. The arginine levels similar to those found in grain-soybean meal swine diets had no effect on pig performance in these experiments.  相似文献   

12.
Interactions among grain type (grain sorghum, corn or wheat), roughage level and monensin level were studied in four feedlot trials using pen-fed crossbred yearling cattle. In Trial 1, cattle fed high-moisture corn (HMC) were more efficient (.1537 vs .1406 for gain/feed; P less than .01) than cattle fed dry-rolled grain sorghum (DRGS). As level (0, 3, 6, 9%) of dietary roughage was increased, feed efficiency (gain/feed) decreased (.1566, .1461, .1479, .1382; linear, P less than .01). In Trial 2, a grain type (DRGS; dry-rolled corn, DRC; dry-rolled wheat, DRW) x roughage level interaction was observed for daily gain and feed efficiency. Feed efficiency (gain/feed) was decreased when roughage was added to diets containing DRC (.1608 vs .1750) or DRGS (.1674 vs .1465), but not to the diet containing DRW (.1664 vs .1607). In trial 3, a grain type x roughage level x monensin level interaction (P less than .08) was observed for feed efficiency. The addition of 27.5 mg of monensin per kilogram of the 0% roughage-DRC diet tended to improve feed efficiency (.1633 vs .1531), but the addition of monensin to the 7.5% roughage-DRC diet tended to depress feed efficiency (.1476 vs .1575). The addition of either roughage (.1493 vs .1420) or monensin (.1500 vs .1413) to the DRW diet improved feed efficiency. In Trial 4, cattle fed a combination of 75% DRW and 25% DRC were more efficient (.1618 vs .1591; P less than .06) than cattle fed DRC. As level of roughage (0, 3.75, 7.5%) increased, feed efficiency decreased linearly (.1645, .1599, .1569; P less than .0001). Monensin had no effect on feed efficiency. The value of feeding roughage and monensin was variable both across grain types and within similar grain types.  相似文献   

13.
Nutritional value of quality protein maize for starter and finisher swine.   总被引：4，自引：0，他引：4  
Growth trials with starter (n = 120, 6.8 kg initially, 28 d of age, Exp. 1) and finisher (n = 70, 59 kg initially, Exp. 2) pigs were conducted to compare quality protein maize (QPM, .40% lysine) and normal corn (.31% lysine) in simple corn-based diets containing the same levels of soybean meal. In Exp. 1, pig performance was similar (P greater than .10) on all diets, regardless of the level of soybean meal, suggesting that QPM and normal corn have similar feeding value in lysine-adequate (.99 to 1.11%) diets. In Exp. 2, less soybean meal was needed in QPM than in normal corn diets to maximize performance; increasing soybean meal from 10.8 to 13.8% improved rate (P less than .05) and efficiency (P less than .01) of gain of pigs fed normal corn diets but had no effect on performance of pigs fed QPM diets. A QPM-based diet containing 6% soybean meal and supplemental lysine and tryptophan failed to maximize feed efficiency, but growth rate was equal to that obtained on the normal corn diet with 13.8% soybean meal. The apparent fecal digestibility of GE and ileal digestibility of N were similar for QPM and normal corn, but apparent ileal digestibility of most essential amino acids was slightly higher for QPM (Exp. 3). Experiment 4 compared apparent digestibilities of QPM, conventional opaque-2 corn and two high-protein corns. Digestibilities differed (P less than .05) among the corns, but the absolute differences were small and were likely due to differences in amino acid content of the corns.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

14.
Two metabolism trials were conducted with yearling steers fed mature native forage to measure the effect of supplemental protein degradability on selected metabolic variables. Supplements contained 40% crude protein equivalence. In Trial 1, four abomasal-cannulated steers weighing 290 to 379 kg were fed supplements containing the following N sources: (1) 15% corn, 85% urea (U); (2) 100% soybean meal (SBM); (3) 10% corn, 40% soybean meal, 50% urea (SBM-U) and (4) 14% corn, 36% blood meal, 50% urea (BM-U). Equal portions of the daily diet (2.2% of body weight) were fed every 2 h. Treatment differences were not significant for organic matter digestibility, abomasal organic matter flow, nonammonia N flow, feed N flow, bacterial N flow and efficiency of microbial protein synthesis. There was a positive (P less than .05) relationship between quantity of slowly degraded protein fed and nonammonia N flow (r = .97) or feed N flow (r = .98). Escape N was determined to be 21.5, 16.5 and 54.2% in SBM, SBM-U and BM-U supplements, respectively. In the second trial, no supplement, SBM, SBM-U and BM-U were fed in a N balance trial. Dry matter, crude protein and neutral detergent fiber digestibilities were higher (P less than .05) for steers fed supplemented diets. Acid detergent fiber digestibility was higher (P less than .05) for steers supplemented with SBM than steers fed the unsupplemented diets. Nitrogen retention was greater (P less than .05) for cattle fed SBM and BM-U than for cattle fed SBM-U or no supplement.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

15.
Four nursery experiments were conducted using a methionine (Met)-deficient feather meal-corn-soybean meal-dried whey basal diet (20% CP; 3,250 kcal of ME/kg, .11% choline, .19% Met, 1.00% cystine) supplemented with lysine, tryptophan, and histidine to determine the Met requirement of 5- to 10- and 10- to 20-kg pigs. Based on a true Met digestibility value of 81.6% estimated by a pig ileal digestibility assay, the Met-deficient basal diet contained .155% of digestible Met. A preliminary experiment (Exp. 1) indicated that pigs fed the Met-deficient basal diet when fortified adequately with Met could produce weight gains similar to those of pigs fed a 20% CP practical corn-soybean meal-dried whey diet. In Exp. 2 and 3, crossbred pigs weighing 5.8 kg initially were fed diets containing graded levels of digestible Met between .195 and .355%. Average daily gain increased quadratically (P less than .05) as the level of Met increased. When the data of Exp. 2 and 3 were examined together, the digestible Met requirement of 5- to 10-kg pigs was estimated to be .255% of the diet. In Exp. 4 and 5, crossbred pigs averaging 10 kg were fed digestible Met concentrations ranging from .155 to .315%. Average daily gain increased quadratically (P less than .05). The digestible Met requirement of 10- to 20-kg pigs was estimated at .255% for maximal weight gain, which was similar to that of 5- to 10-kg pigs. Assuming an 89% digestibility of Met in practical corn-soybean meal diets, the total Met level needed in practice would be .29%.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

16.
Fifty-eight Holstein and 58 crossbred beef steers were individually fed one of four isonitrogenous diets to evaluate the effects of forage source (corn silage and alfalfa haylage) and protein source (soybean meal and fish meal) on feedlot performance. Phase 1 diets (up to 354 kg of BW) were 40% forage and 60% concentrates and were fed for 70 to 136 d (depending on diet and breed group). Phase 2 diets (354 kg of BW until slaughter) were 20% forage and 80% concentrates and were fed for 127 to 150 d (depending on diet and breed group). Slaughter end points were .6 cm of 12th rib fat for Holsteins and 1.0 cm of rib fat for crossbreds using real-time ultrasonic estimates. The steers were fed for a maximum of 330 d each year. Forage source was a significant component of variation for most growth, efficiency, and carcass traits. Holstein and crossbred steers fed alfalfa haylage had significantly lower average daily gain, feed efficiency, dressing percentage, and empty body fat and required more days on feed to reach slaughter end points, but had higher total feed energy intake available for production. Steers fed corn silage diets had significantly greater energetic efficiency (P less than .05) than those fed alfalfa haylage, due to increased use of ME to produce fat in the carcass. Protein type did not influence gain, feed or energetic efficiency, energy intake, or most carcass traits. A significant protein system x forage source interaction among the four diets was detected for crossbred steers fed corn silage and fish meal, for which there was significantly greater feed conversion with lower energy intake above maintenance, possibly due to better fiber digestion and(or) amino acid flow to the lower tract. Alfalfa haylage plus soybean meal diets decreased (P less than .05) the percentage of Holsteins grading USDA Choice or higher. These results indicate that corn silage, because of greater energy concentration, was a more desirable forage in feedlot diets composed of less than or equal to 40% forage and that protein type (soybean meal and fish meal) in growing diets is not an important factor in feedlot performance or carcass traits of Holstein or crossbred steers that are fed these diets.  相似文献   

17.
Two trials were conducted to determine the suitability of soybean products for baby pigs. Weanling pigs (n = 40 and 48 in Trials 1 and 2, respectively) were infused orally (6 g/d) with dried skim milk, soybean meal (SBM, 48% CP); soy protein concentrate, moist extruded soy protein concentrate, or soy protein isolate from d 7 to 12 of age. Pigs were then fed a diet containing the same protein source for 1 (Trial 1) or 2 (Trial 2) wk after weaning (d 21 of age). To avoid exposure of pigs to soybean proteins, the dams of pigs were fed a corn-corn gluten meal-based diet supplemented with lysine and tryptophan from d 109 of gestation. All pigs in Trial 1 were killed at 28 d of age, and samples of ileal digesta and small intestine were obtained. In Trial 2, the soy protein isolate was not included, and all pigs were fed a diet containing 4% soybean oil and 1.25% lysine for the last 3 wk of the trial. Growth performance, skin-fold thickness, after intradermal injection of extracts of the corresponding proteins, and anti-soy immunoglobulin G (IgG) titers were measured. Results indicated that pigs fed diets containing SBM had lower (P less than .05) villus height and xylose absorption but higher (P less than .05) serum anti-soy IgG titers and increased skin-fold thickness compared with the mean of pigs given milk and all other soy treatments.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

18.
The effect of dietary citric acid (CA) and fumaric acid (FA) on pig weight gain (ADG) and gain/feed (G/F) was studied in two trials using 192 crossbred, 4-wk-old weaning pigs. Three dietary levels (0, 1.5 or 3.0%) of either FA (Trial 1) or CA (Trial 2) with or without an antibiotic supplement (110 mg chlortetracycline, 110 mg sulfamethazine and 55 mg penicillin/kg diet) formed six treatment combinations in each trial. These six diets were fed to two replicate pens of eight pigs each for a 4-wk period. In Trial 1, ADG was improved (P less than .01) during wk 1, and G/F was improved during wk 1 (P less than .01) as well as during wk 1 to 2 (P less than .05) for pigs consuming FA-supplemented diets. In Trial 2, CA had no beneficial influence on ADG during the 4-wk trial. However, feed intake during wk 1 was depressed (P less than .05) by adding CA, as was G/F during wk 1 to 2 (P less than .05). Based on these results, FA was selected to be used in a nutrient balance study. Twelve 4-wk-old weanling pigs were fed one of three diets: control (C), C + 1.5% FA, or C + antibiotic supplement (A). Diet digestible energy (DE), ME and N-corrected ME (MEN) were not different among treatments. Nitrogen balance, percentage N retained and apparent N digestibility were not affected by dietary treatment. Calcium balance and percentage of Ca retained were unaffected by diet.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

19.
Two experiments were conducted using corn from clean or aflatoxin B1 (AFB1)-contaminated (182 ppb) sources. Weanling pigs (28 d) were fed one of eight dietary treatments arranged in a 2 x 2 x 2 factorial design. In Exp. 1 (192 pigs), treatments varied in corn source (clean or AFB1-contaminated), CP level (18 or 20%) and added fat (0 or 5%). At the end of the 28-d growth trials, plasma samples were obtained. An AFB1 x CP level interaction was detected (P less than .05) for growth rate (ADG), feed intake (FI) and feed/gain ratio (F/G). Feeding AFB1 reduced (P less than .05) ADG (.30 vs .37 kg/d) and FI (.57 vs .66 kg/d) and increased F/G (1.88 vs 1.78) of pigs fed 18% CP diets. Performance of pigs fed 20% CP diets was not altered by AFB1. Adding 5% fat to diets improved (P less than .05) F/G but did not improve ADG of pigs fed AFB1. There was an AFB1 x CP x fat interaction (P less than .05) for plasma cholesterol. Adding fat or increasing the CP level prevented the depression of plasma cholesterol in pigs fed AFB1. In Exp. 2 (96 pigs), all diets contained 18% CP and the treatments varied in corn source (clean or AFB1-contaminated), added L-lysine HCl (0 or .25%) and added DL-methionine (0 or .15%). Feeding AFB1 reduced (P less than .05) ADG of pigs fed the 18% CP diet (.44 vs .50 kg/d) but not of pigs fed diets supplemented with .25% lysine.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

20.
In a series of five trials, 680 crossbred pigs were fed isolysine diets in which high protein (13.8 to 16.0%) oats constituted 0, 20, 40 or 60% of the cereal portion. There was a linear depression in average daily gain (P less than .001) and average daily feed intake (P less than .005) with increasing level of oats, but feed/gain was unaffected (P less than .05) during the growing period from 22 to 46 kg. There were no significant differences in average daily gain during the finishing period from 46 to 102 kg; however, feed/gain increased linearly (P less than .01) with increasing level of oats in the diet. Increases in the percentage of oats in the cereal portion of the diet resulted in a linear (P less than .01) decrease in average daily gain and an increase (P less than .01) in feed/gain for the entire feeding period. We conclude that high protein-high lysine oats of the quality used in these trials can be included at up to 20% of the cereal portion of the diet without greatly affecting performance.  相似文献   

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