Effect of dietary copper source (cupric citrate and cupric sulfate) and concentration on growth performance and fecal copper excretion in weanling pigs

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.     

Effect of dietary mannan oligosaccharides and(or) pharmacological additions of copper sulfate on growth performance and immunocompetence of weanling and growing/finishing pigs

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.     

The effect of copper and fat addition to the diets of weanling swine on growth performance and serum fatty acids.

A 2 x 3 factorial experiment, encompassing three 28-d trials involving a total of 420 weanling pigs, was conducted to determine the effect of dietary Cu (5 or 250 ppm) and animal fat (0, 2.5, or 5%) on the performance and serum fatty acid profiles of weanling pigs. Pigs had ad libitum access to corn-soybean meal-based diets containing 10% whey and 5% fish meal and similar lysine:calorie ratios. Pigs were weighed and pen feed intakes were recorded weekly. Weekly blood samples were collected during the first two trials (n = 270) for serum fatty acid analysis. There was a Cu x fat interaction for ADG from d 1 to 14 (P less than .07) and over the 28-d experiment (P less than .05). The ADG of pigs fed 250 ppm of Cu increased, whereas the ADG of pigs fed 5 ppm of Cu was not affected as dietary fat increased. The addition of 250 ppm of CU increased (P less than .01) ADFI throughout the 28-d experiment. The addition of fat quadratically increased ADG (P less than .05) during d 14 to 28 and gain:feed ratios (P less than .01) during d 14 to 28 and over the 28-d experiment. The addition of fat decreased (P less than .05) the weight percentage of serum saturated fatty acids and increased (P less than .01) the weight percentage of serum monounsaturated fatty acids on d 28. The addition of 250 ppm of Cu decreased (P less than .01) the weight percentage of monounsaturated fatty acids on d 14 and 28.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of chelated copper sources on performance of nursery and growing pigs

Four experiments were conducted to determine the effect of Cu source and level and an antimicrobial agent on performance of nursery (6 to 25 kg) and growing (20 to 65 kg) pigs. Copper was fed either as CuSO4.5H2O (CS), inorganic chelated Cu (ICC) or organic chelated Cu (OCC) to provide 31.25 to 250 ppm supplemental Cu. In Exp. 1, 224 pigs were used to study Cu source and level added to nursery diets. No difference (P less than .05) among treatments was observed during the nursery period. Treatments were continued the first 56 d of the growing-finishing period. Regardless of the Cu source, pigs receiving 125 ppm added Cu gained faster (P less than .05) than pigs in other treatments. In Exp. 2, 216 pigs were used to determine the optimum level of CS and ICC in nursery diets. Pigs were less efficient (P less than .01) when Cu was added at 62.5 and 125 ppm than at 250 ppm (1.69, 1.72 and 1.59, feed/gain respectively). In Exp. 3, no differences (P greater than .05) in performance between sources or among levels of Cu were found. In Exp. 4, 216 pigs were utilized to determine the combined effects of Cu source and an antimicrobial on performance. Pigs fed ICC were less efficient (P less than .01) than pigs fed either OCC or CS (1.99, 1.85 and 1.90, respectively). The inorganic and organic chelated Cu compounds used in these studies were not more efficacious than CS for nursery or growing pigs.     

Effects of chito-oligosaccharide supplementation on the growth performance, nutrient digestibility, intestinal morphology, and fecal shedding of Escherichia coli and Lactobacillus in weaning pigs

A total of 50 weaning pigs (16 d of age; 4.72 +/- 0.23 kg of BW) were selected to investigate the effect of dietary chito-oligosaccharide (COS) supplementation on growth performance, fecal shedding of Escherichia coli and Lactobacillus, apparent digestibility, and small intestinal morphology. Pigs housed in individual metabolic cages were assigned randomly to 5 treatments (n = 10), including 1 basal diet (control), 3 diets with COS supplementation (100, 200, and 400 mg/kg), and 1 diet with chlortetracycline (CTC) supplementation (80 mg/kg). Fresh fecal samples were collected to evaluate shedding of E. coli and Lactobacillus on d 0, 7, 14, and 21 postweaning. Fresh fecal samples collected from each cage from d 19 to 21 were stored frozen for determination of apparent total tract digestibility. On d 21, all pigs were killed to collect the middle sections of the duodenum, jejunum, and ileum for determination of mucosa morphology. Supplementation of COS at 100 and 200 mg/kg and supplementation of CTC improved (P < 0.05) overall ADG, ADFI, and G:F in comparison with the control. Supplementation of COS at 200 mg/kg as well as supplementation of CTC increased (P < 0.05) apparent total tract digestibility of DM, GE, CP, crude fat, Ca, and P, whereas COS at 100 mg/kg increased (P < 0.05) the digestibility of DM, Ca, and P in comparison with the control diet. Pigs receiving diets supplemented with COS or CTC had a decreased (P < 0.05) incidence of diarrhea and decreased diarrhea scores compared with control pigs. Fecal samples from pigs receiving diets supplemented with COS had greater (P < 0.05) Lactobacillus counts than those from control pigs and pigs receiving diets supplemented with CTC on d 14 and 21. However, supplementation of COS at 200 mg/kg and supplementation of CTC decreased (P < 0.05) E. coli counts in the feces on d 21 compared with the control diet. Dietary supplementation of COS at 200 mg/kg and of CTC increased (P < 0.05) the villus height and villus:crypt ratio at the ileum and jejunum, and COS at 100 mg/kg also increased (P < 0.05) the villus height in the ileum compared with the control diet. The current results indicated that dietary supplementation of COS at 100 and 200 mg/kg enhanced growth performance by increasing apparent digestibility, decreasing the incidence of diarrhea, and improving small intestinal morphology.     

罗格列酮对断奶仔猪肠黏膜结构和抗氧化能力的影响

试验研究罗格列酮(ROS)对脂多糖(LPS)刺激的断奶仔猪肠黏膜结构和抗氧化能力的影响。试验包括3个处理组,对照组注射生理盐水,LPS组注射100μg/kg体重的LPS,ROS组在注射LPS之前的30min注射3mg/kg体重的ROS。注射LPS3h后取样。结果表明:ROS提高了十二指肠和回肠DNA的含量(P0.05);ROS缓解了LPS导致的十二指肠、空肠和回肠隐窝深度的增加(P0.10)和绒毛高度/隐窝深度的降低(P0.01);ROS降低了空肠丙二醛含量(P0.10),提高了十二指肠和空肠SOD活性(P0.05)。结果表明,ROS可能是通过提高肠道抗氧化功能而对LPS刺激的断奶仔猪小肠形态结构的损伤起到一定保护作用。     

The effect of copper addition to diets with various iron levels on the performance and hematology of weanling swine

A 2 x 6 factorial experiment with Cu added at 5 or 250 ppm and Fe added at 50, 100, 150, 200, 250, or 300 ppm was conducted using 480 crossbred weanling pigs with an average initial weight of 7.0 kg. The basal corn-soybean meal-whey diet contained 4 ppm Cu, 169 ppm Fe, and 199 ppm Zn. Pigs were allotted by weight, sex, and litter outcome group and had ad libitum access to feed and water during the 28-d trials. Animals were weighed and pen feed intake was recorded weekly. Blood samples were collected on d 1, 14, and 28 of the experiment. The addition of 250 ppm Cu increased ADG (P less than .001) and average daily feed intake (ADFI, P less than .01) during the 28-d trials. The addition of Fe had no effect on ADG and ADFI (P greater than .10). A Cu x Fe interaction (P less than .01) was observed for feed/gain. Increasing Fe levels linearly improved hematocrit status (P less than .05) on d 28 of the trial. A Cu x Fe interaction (P less than .08) was observed for hemoglobin at the end of the trial; hemoglobin levels were increased by the addition of Fe to the diet containing 250 ppm of Cu. Plasma Cu was increased (P less than .001) by the addition of 250 ppm of Cu. Plasma Fe was low when either 50 or 100 ppm of Fe was added in the presence of 250 ppm of Cu, but it was not affected at other levels, resulting in a Cu x Fe interaction (P less than .05). These data indicate that levels of added Fe up to 300 ppm may help to improve the hematological status of weanling pigs fed growth-promoting levels of Cu but that it has little effect on performance.     

Interactive effects of sodium zeolite-A and copper in growing swine: growth, and bone and tissue mineral concentrations.

An experiment was conducted with 64 crossbred pigs to determine the effect of 0 or .50% dietary sodium zeolite-A (NZA) in combination with 0 or 250 ppm supplemental Cu (as CuSO4.5H2O). Pigs were assigned randomly to one of the following four treatments: 1) corn-soybean meal basal (B), 2) B + .50% NZA, 3) B + 250 ppm Cu, or 4) B + .50% NZA + 250 ppm Cu. Each treatment was replicated four times with four pigs per replicate. Average initial weight was 7.5 kg and the experimental period lasted 144 d. Overall rate and efficiency of gain, incidence of gastric ulcers, dressing percentage, carcass weight, percentage of muscling, 10th rib fat, loin eye area, blood urea N, and bone Ca, P, Mn, Fe, Ni, Na, and Al concentrations were not affected by treatment. The addition of 250 ppm Cu increased liver (P less than .01), serum (P less than .06), and bone (P less than .07) Cu concentrations but decreased mean backfat thickness (P less than .09), bone ash percentage (P less than .03) and serum (P less than .09) and bone (P less than .01) Zn concentrations. Sodium zeolite-A increased serum alkaline phosphatase (P less than .04), carcass length (P less than .06), and liver (P less than .02) and bone (P less than .01) Zn content but decreased (P less than .04) serum Ca and serum inorganic P concentrations. Sodium zeolite-A did not protect against liver Cu accumulation or gastric ulceration in growing swine fed 250 ppm supplemental Cu.     

Lipid microencapsulation allows slow release of organic acids and natural identical flavors along the swine intestine

The purpose of the present work was to investigate the in vivo concentrations of sorbic acid and vanillin as markers of the fate of organic acids (OA) and natural identical flavors (NIF) from a microencapsulated mixture and from the same mixture non-microencapsulated, and the possible consequences on the intestinal microbial fermentation. Fifteen weaned pigs were selected from 3 dietary groups and were slaughtered at 29.5 +/- 0.27 kg of BW. Diets were (1) control; (2) control supplemented with a blend of OA and NIF microencapsulated with hydrogenated vegetable lipids (protected blend, PB); and (3) control supplemented with the same blend of OA and NIF mixed with the same protective matrix in powdered form but without the active ingredient coating (non-protected blend, NPB). Stomach, cranial jejunum, caudal jejunum, ileum, cecum, and colon were sampled to determine the concentrations of sorbic acid and vanillin contained in the blend and used as tracers. Sorbic acid and vanillin were not detectable in pigs fed the control, and their concentrations were not different in the stomach of PB and NPB treatments. Pigs fed PB showed a gradual decrease of the tracer concentrations along the intestinal tract, whereas pigs fed NPB showed a decline of tracer concentration in the cranial jejunum and onwards, compared with the stomach concentrations. Sorbic acid and vanillin concentrations along the intestinal tract were greater (P = 0.02) in pigs fed PB compared with pigs fed NPB. Pigs fed PB had lower (P = 0.03) coliforms in the caudal jejunum and the cecum than pigs fed the control or NPB. Pigs fed the control or PB had a greater (P = 0.03) lactic acid bacteria plate count in the cecum than pigs fed NPB, which showed a reduction (P = 0.02) of lactic acid concentrations and greater (P = 0.02) pH values in the caudal jejunum. The protective lipid matrix used for microencapsulation of the OA and NIF blend allowed slow-release of both active ingredients and prevented the immediate disappearance of such compounds upon exiting the stomach.     

Copper proteinate in weanling pig diets for enhancing growth performance and reducing fecal copper excretion compared with copper sulfate

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.     

Comparison of growth performance and zinc absorption, retention, and excretion in weanling pigs fed diets supplemented with zinc-polysaccharide or zinc oxide

Fifty weanling crossbred pigs averaging 6.2 kg of initial BW and 21 d of age were used in a 5-wk experiment to evaluate lower dietary concentrations of an organic source of Zn as a Zn-polysaccharide (Zn-PS) compared with 2,000 ppm of inorganic Zn as ZnO, with growth performance, plasma concentrations of Zn and Cu, and Zn and Cu balance as the criteria. The pigs were fed individually in metabolism crates, and Zn and Cu balance were measured on individual pigs (10 replications per treatment) from d 22 to 26. The basal Phase 1 (d 0 to 14) and Phase 2 (d 14 to 35) diets contained 125 or 100 ppm added Zn as Zn sulfate, respectively, and met all nutrient requirements. Treatments were the basal Phase 1 and 2 diets supplemented with 0, 150, 300, or 450 ppm of Zn as Zn-PS or 2,000 ppm Zn as ZnO. Blood samples were collected from all pigs on d 7, 14, and 28. For pigs fed increasing Zn as Zn-PS, there were no linear or quadratic responses (P > or = 0.16) in ADG, ADFI, or G:F for Phases 1 or 2 or overall. For single degree of freedom treatment comparisons, Phase 1 ADG and G:F were greater (P < or = 0.05) for pigs fed 2,000 ppm Zn as ZnO than for pigs fed the control diet or the diet containing 150 ppm Zn as Zn-PS. For Phase 2 and overall, ADG and G:F for pigs fed the diets containing 300 or 450 ppm of Zn as Zn-PS did not differ (P > or = 0.29) from pigs fed the diet containing ZnO. Pigs fed the diet containing ZnO also had a greater Phase 2 (P < or = 0.10) and overall (P < or = 0.05) ADG and G:F than pigs fed the control diet. There were no differences (P > or = 0.46) in ADFI for any planned comparison. There were linear increases (P < 0.001) in the Zn excreted (mg/d) with increasing dietary Zn-PS. Pigs fed the diet containing ZnO absorbed, retained, and excreted more Zn (P < 0.001) than pigs fed the control diet or any of the diets containing Zn-PS. In conclusion, Phase 2 and overall growth performance by pigs fed diets containing 300 or 450 ppm Zn as Zn-PS did not differ from that of pigs fed 2,000 ppm Zn as ZnO; however, feeding 300 ppm Zn as Zn-PS decreased Zn excretion by 76% compared with feeding 2,000 ppm Zn as ZnO.     

Inclusion of dicopper oxide instead of copper sulfate in diets for growing–finishing pigs results in greater final body weight and bone mineralization,but reduced accumulation of copper in the liver

An experiment was conducted to test the hypothesis that inclusion of Cu oxide (Cu₂O) in diets for growing–finishing pigs improves body weight (BW) and bone mineralization, and reduces accumulation of Cu in the liver compared with pigs fed diets containing Cu sulfate (CuSO₄). Two hundred growing pigs (initial BW: 11.5 ± 0.98 kg) were allotted to a randomized complete block design with 2 blocks of 100 pigs, 5 dietary treatments, 5 pigs per pen, and a total of 8 pens per treatment. Treatments included the negative control (NC) diet that contained 20 mg Cu/kg, and 4 diets in which 125 or 250 mg Cu/kg from CuSO₄ or Cu₂O were added to the NC diet. The experiment was divided into 4 phases and concluded when pigs reached market weight. Pig weights were recorded on day 1 and at the end of each phase and feed provisions were recorded throughout the experiment. On the last day of phases 1 and 4, 1 pig per pen was sacrificed to obtain samples of liver and spleen tissue, and the right metacarpal was collected. Results indicated that pigs fed diets containing 250 mg Cu/kg from CuSO₄ had greater BW at the end of phases 1 and 2 than pigs fed NC diets. Pigs fed diets containing 250 mg Cu/kg from Cu₂O had greater (P < 0.05) BW at the end of phases 1, 2, 3, and 4 compared with pigs fed NC diets, and these pigs also had greater BW at the end of phases 3 and 4 than pigs fed all other diets. Pigs fed the diets with 250 mg Cu/kg tended to have greater (P < 0.10) feed intake than pigs fed the NC diet at the end of phase 2, and for the overall experimental period, pigs fed diets containing 250 mg Cu/kg from Cu₂O had greater (P < 0.05) feed intake than pigs on all other treatments. However, no differences in gain:feed ratio were observed among treatments. Copper accumulation in liver and spleen increased with Cu dose, but at the end of phase 1, pigs fed 250 mg Cu/kg from CuSO₄ had greater (P < 0.05) Cu concentration in liver and spleen than pigs fed 250 mg Cu/kg from Cu₂O. Pigs fed diets containing 250 mg Cu/kg from Cu₂O had greater (P < 0.05) quantities of bone ash and greater (P < 0.05) concentrations of Ca, P, and Cu in bone ash than pigs fed NC diets or the 2 diets containing CuSO₄, but Zn concentration in bone ash was less (P < 0.05) in pigs fed diets containing 250 mg Cu/kg from Cu₂O. To conclude, supplementing diets for growing pigs with Cu₂O improves growth performance and bone mineralization with less Cu accumulation in liver compared with pigs fed diets containing CuSO₄.     

Effects of ethanol extraction and heat treatment of soybean flakes on function and morphology of pig intestine

Digesta and tissue samples were collected from the intestinal tracts of 27 pigs to determine the relationship between intestinal morphology and the utilization of nutrients from soybean flakes. Soybean flake treatments were under-, intermediate- and over-processed (i.e., 5, 20 and 60 min of autoclaving) either without extraction or with heating before or after extraction with a 55% ethanol-water mixture. Final BW was greatest (P less than .001) for pigs fed soybean flakes given 20 min of heat treatment. There was a trend (P less than .09) for plasma lysine concentrations to be reduced when the unextracted soybean flakes were over-processed (60 min of heat). Differences in the flow rate of DM and N through the ileum and colon reflected differences in DM and N intake, rather than differences in intestinal function. The soybean flake treatments had no effect (P greater than .08) on pH of the contents of the stomach, duodenum, ileum or colon. The ethanol extraction process increased (P less than .001) N digestibility of the soybean flakes, especially when the soybean flakes were underprocessed (interaction, P less than .02). Villus size (area, height and perimeter length) tended to be greater in pigs fed the soybean flakes heated after extraction and(or) exposed to the intermediate level of heat treatment. Indicators of villus shape (villus area/villus height) and proliferative activity (crypt depth and villus height/crypt depth) were not affected by soybean flake treatment (P greater than .08). Ethanol extraction and heat treatment affected the utilization of nutrients from soybean flakes.(ABSTRACT TRUNCATED AT 250 WORDS)     

The Effect of Dietary Sulphate Copper Supplementation on Growth Performance, Intestinal Digestive Enzymes and Absorptive Transporters in Weanling Pigs

The experiment was conducted to assess the effects of dietary supplementation of Cu on the growth performance,digestive enzymes,tissue minerals and absorptive transporters in small intestinal mucosa of weanling pigs.One hundred crossbred pigs weaned at 28±2 d of age were assigned randomly to one of the following diets with 5 replicates:corn-soybean basal diet with 10,100,175,250 mg/kg of Cu as CuSO4·5H2O.The results showed that 250 mg/kg Cu had a positive effect (P0.05) on average daily gain,daily feed intake and ratio of gain/feed.Compared to 10 mg/kg Cu,higher Cu had significant effect on the apparent digestibility of protein and fat (P0.05).The supplementing of Cu improved amylase and lipase activity in jejunum content and lipase in pancreas (P0.05) and had no effect on intestinal morphology.The liver Cu elevated approximately 4-fold in pigs fed diet with 250 mg/kg Cu compared with pigs fed diet with 10 mg/kg Cu,no increases were observed in pigs receiving the lower level of Cu (100 and 175 mg/kg).Both Fe and Zn contents in kidney and liver were not affected by Cu supplementation.There was no positive effect (P0.05) of Cu supplementation on PepT1 (peptide transporter 1) and SGLT1 (sodium/glucose cotransporter) mRNA abundance in intestinal mucosa.However,higher supplementing level (250 mg/kg) significantly elevated the DMT1 (divalent metal transporter) mRNA abundance in duodenum mucosa.These results suggested that dietary supplementation with 250 mg/kg Cu could improve growth performance,nutrient digestibility and intestinal enzyme activities of weanling pigs.     

Granulated lysozyme as an alternative to antibiotics improves growth performance and small intestinal morphology of 10-day-old pigs

Lysozyme is a 1,4-β-N-acetylmuramidase that has antimicrobial properties. The objective of this experiment was to determine the effect of a purified granulated lysozyme, compared with antibiotics, on growth performance, small intestinal morphology, and Campylobacter shedding in 10-d-old pigs. Forty-eight pigs (n = 16 per treatment), with an initial BW of 4.0 ± 0.1 kg (P > 0.40), were weaned at 10 d of age, blocked by litter and sex, and assigned to pens (8 pigs/pen). Each block was randomly assigned to consume 1 of 3 liquid dietary treatments for 14 d: a control diet, the control diet + lysozyme (100 mg/kg of diet), or the control diet + antibiotics (neomycin and oxytetracycline, 16 mg/kg of diet). Pigs were weighed and blood was sampled on d 0, 7, and 14. Blood was analyzed for plasma urea N and IgA. After 14 d of treatment, pigs were killed and samples of the jejunum and ileum were collected and fixed to measure villus height and crypt depth. Rectal swabs were taken on d 0, 7, and 14 of treatment, and samples of ileal and cecal contents were taken at d 14 of treatment to determine the presence of Campylobacter. Pigs consuming lysozyme and antibiotics gained BW at a faster rate than did control pigs over the course of the study (402 ± 12 and 422 ± 14 g/d, respectively, vs. 364 ± 14 g/d; P < 0.02), resulting in heavier ending BW (9.9 ± 0.3, 9.9 ± 0.3, and 9.0 ± 0.2 kg for pigs in the lysozyme, antibiotic, and control groups, respectively; P < 0.03). Immunoglobulin A decreased and plasma urea N increased over the course of the study (P < 0.1), regardless of dietary treatment (P > 0.6). Crypt depth was increased in pigs fed lysozyme- and antibiotic-treated diets, compared with pigs fed the control diet, in both the jejunum (60.0 ± 2.8 and 62.2 ± 3.0 μm, respectively, vs. 50.7 ± 3.1 μm; P < 0.03) and ileum (76.0 ± 7.5 and 72.2 ± 5.0 μm, respectively, vs. 52.4 ± 3.5 μm; P < 0.02). Villus height did not differ in the jejunum (P > 0.2) but was increased in the ileum of pigs consuming the lysozyme- and antibiotic-treated diets, compared with pigs fed the control diet (312 ± 20 and 314 ± 10 μm, respectively, vs. 263 ± 15 μm; P < 0.4). Small intestinal total mucosa and mucosal protein concentrations, as well as disaccharidase-specific activities, were not altered by lysozyme or antibiotics (P > 0.05). Campylobacter was detected in 27% of control samples but in only 5% of samples from pigs fed antibiotics and 8% of samples from pigs fed lysozyme (P < 0.01). Thus, granulated lysozyme is a suitable alternative to antibiotics for 10-d-old pigs consuming manufactured liquid diets.     

Physiological relationships between microbiological status and dietary copper levels in the pig

Ten germ-free pigs and 10 conventionally reared pigs were fed one of two nutritionally balanced diets containing either 16 ppm Cu (basal) or 283 ppm Cu (high-Cu) to evaluate the physiological relationships between Cu and microbiological environment. Germ-free pigs tended to have higher ADG and average daily feed intake (ADFI) than conventionally reared pigs. Feeding the high-Cu diet tended to reduce ADG and ADFI in germ-free pigs but it increased ADG and ADFI in conventionally reared pigs. Hemoglobin and hematocrit were higher in germ-free pigs than in conventionally reared pigs (P less than .001), and hematocrit (P less than .01) and erythrocyte count (P less than .06) were reduced by feeding the high-Cu diet. Germ-free pigs had lower total leukocyte count (P less than .01) and the relative percentages of differentiated leukocytes were altered compared with conventionally reared pigs. Feeding the high-Cu diet increased the percentage of band neutrophils and monocytes in germ-free pigs but reduced the percentage of these cells in conventionally reared pigs (P less than .04). Germ-free pigs had higher concentrations of Cu and Zn in liver and plasma (P less than .001) and greater plasma ceruloplasmin oxidase activity (P less than .001) than conventionally reared pigs did. The high-Cu diet increased liver Cu and Zn (P less than .001) and plasma Cu (P less than .001) and reduced liver and plasma Fe (P less than .05). Organ weights (g/kg BW) differed between germ-free and conventionally reared pigs, and feeding the high-Cu diet reduced thymus weights (P less than .002). Intestinal weight and thickness were reduced in germ-free pigs, and feeding the high-Cu diet generally reduced villus height and width and crypt depth in germ-free pigs, whereas it increased these measurements in conventionally reared pigs.     

The Effect of Dietary Sulphate Copper Supplementation on Growth Performance, Intestinal Digestive Enzymes and Absorptive Transporters in Weanling Pigs

The experiment was conducted to assess the effects of dietary supplementation of Cu on the growth performance, digestive enzymes, tissue minerals and absorptive transporters in small intestinal mucosa of weanling pigs. One hundred crossbred pigs weaned at 28 ± 2 d of age were assigned randomly to one of the following diets with 5 replicates: corn-soybean basal diet with 10, 100, 175, 250 mg/kg of Cu as CuSO₄•5H₂O. The results showed that 250 mg/kg Cu had a positive effect (P < 0.05) on average daily gain, daily feed intake and ratio of gain/feed. Compared to 10 mg/kg Cu, higher Cu had significant effect on the apparent digestibility of protein and fat (P < 0.05). The supplementing of Cu improved amylase and lipase activity in jejunum content and lipase in pancreas (P < 0.05) and had no effect on intestinal morphology. The liver Cu elevated approximately 4-fold in pigs fed diet with 250 mg/kg Cu compared with pigs fed diet with 10 mg/kg Cu, no increases were observed in pigs receiving the lower level of Cu (100 and 175 mg/kg). Both Fe and Zn contents in kidney and liver were not affected by Cu supplementation. There was no positive effect (P > 0.05) of Cu supplementation on PepT1 (peptide transporter 1) and SGLT1 (sodium/glucose cotransporter) mRNA abundance in intestinal mucosa. However, higher supplementing level (250 mg/kg) significantly elevated the DMT1 (divalent metal transporter) mRNA abundance in duodenum mucosa. These results suggested that dietary supplementation with 250 mg/kg Cu could improve growth performance, nutrient digestibility and intestinal enzyme activities of weanling pigs.     

Response of barrows to space allocation and ractopamine

An experiment using 264 crossbred barrows was conducted to examine the interaction between space allocation and dietary ractopamine addition on pig performance and carcass characteristics using a 2 x 2 factorial arrangement of treatments. Treatments were 0.55 (19 pigs per pen) or 0.74 (14 pigs per pen) m2/pig from start (29.7 +/- 0.1 kg BW) to slaughter (108 kg BW) in a fully slatted facility and 0 or 10 ppm (as-fed basis) ractopamine for 28 d before slaughter. There were few treatment interactions. Pigs given 0.55 m2/pig had a lower ADG (P = 0.010), ADFI (P = 0.088), 10th-rib backfat depth on d 86 (P = 0.010), and carcass loin muscle depth (P = 0.011) than pigs given 0.74 m2/pig. There was no difference in feed conversion (P = 0.210) as a result of space allocation. Pigs fed diets containing 10 ppm ractopamine had decreased (P = 0.004) ADFI and improved (P = 0.001) feed conversion efficiencies for the 28-d feeding period, along with greater loin depth (P = 0.005) and carcass lean percent (P = 0.001). The improvements in 28-d carcass lean growth associated with feeding 10 ppm ractopamine resulted in an improvement in overall daily fat-free lean gain (P = 0.046). Under these experimental conditions, the response to dietary ractopamine was similar for crowded and uncrowded pigs.     

Effects of beta-glucan extracted from Saccharomyces cerevisiae on growth performance, and immunological and somatotropic responses of pigs challenged with Escherichia coli lipopolysaccharide

Three experiments were conducted to investigate the effects of beta-glucan supplementation on pig performance and immune function. In Exp. 1, 100 weaned pigs (8.65 +/- 0.42 kg of BW and 28 +/- 2 d of age) were used in a 35-d experiment to determine the effects of graded levels of beta-glucan. Pigs were randomly allotted to 1 of 5 treatments containing beta-glucan supplemented at 0, 25, 50, 100, or 200 ppm. Each treatment was replicated using 5 pens containing 4 pigs per pen. The ADG of pigs between d 14 to 28 and d 0 to 28 responded to dietary beta-glucan in a quadratic fashion (P < 0.05), whereas beta-glucan had no effect on ADFI and G:F in any period. In Exp. 2, 80 crossbred pigs (8.23 +/- 0.56 kg of BW and 28 +/- 2 d of age) were used in a 35-d experiment. Pigs were allotted to 1 of 2 dietary treatments (0 or 50 ppm of beta-glucan in the diet) using 10 pens with 4 pigs per pen. Pigs treated with beta-glucan had greater ADG in the 14- to 28-d (P = 0.05) and 0-to 28-d (P = 0.035) periods. The ADFI of pigs receiving beta-glucan was increased (P < 0.05) in the periods from 0 to 14, 0 to 28, and 28 to 35 d. The lymphocyte proliferation index in response to phytohemagglutinin (P = 0.051) and concanavalin A (P = 0.052) tended to decrease on d 14 in pigs supplemented with beta-glucan compared with pigs without supplementation. In Exp. 3, 24 barrows (8.89 +/- 0.20 kg of BW and 28 d of age) were used to investigate the immunological and somatotropic responses of pigs challenged with lipopolysaccharide (LPS). Experimental treatments were arranged in a 2 x 2 factorial, with the main effects of LPS challenge (saline vs. LPS) and dietary addition of beta-glucan (0 vs. 50 ppm). Pigs were raised individually in metabolic cages. Pigs were fed 0 or 50 ppm of beta-glucan for 28 d and then challenged with LPS (25 microg/kg of BW) or saline. After LPS injection, blood was obtained at 0, 1.5, 3, 4.5, 6, and 7.5 h to determine cytokine production and the somatotropic response. Dietary beta-glucan increased plasma interleukin-6 at 1.5, 3, and 4.5 h and tumor necrosis factor-alpha at 3 and 4.5 h and increased plasma interleukin-10 from 3 to 7.5 h after LPS challenge. The beta-glucan treatments had no effect on growth hormone. In conclusion, beta-glucan can selectively influence performance and partially offer benefits on somatotropic axis and immune function in weaned piglets challenged with LPS.