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1.
Ninety-six pigs (initially 8.9 kg and 24 d of age) were used in a 28-d experiment to determine the effects of Quillaja saponaria extract (QS) on weanling pig growth performance and immune function in response to enteric disease challenge with Salmonella typhimurium (ST). Experimental treatments were arranged in a 2 x 4 factorial with main effects of disease challenge (control vs ST-challenge) and dietary addition of QS (0, 125, 250, or 500 mg/kg). Pigs were fed QS diets for 14 d and then challenged orally with ST or sterile media. There were no differences in ADG or ADFI among dietary treatments, but gain/feed ratio (G/ F) was depressed (P < 0.06) in pigs fed 250 mg/kg QS. ST-challenge reduced ADG (P < 0.05), ADFI (P < 0.05), and G/F (P < 0.05) 1 wk after challenge. Daily estimates revealed reductions in feed intake in ST-infected pigs on d 2 to 5 following infection (P < 0.05), and rectal temperature was increased maximally 2 d following infection (P < 0.05). There was a marked decline in serum IGF-I during the 6 d after ST-infection (P < 0.05). ST-challenge produced a rise (P < 0.05) in serum haptoglobin on d 7 after challenge, and serum alpha1-acid glycoprotein (AGP) in ST-challenged pigs also was elevated (P < 0.05) above controls on d 7 and 14 after challenge. Serum immunoglobulin (Ig) M increased (P < 0.05) over time in both groups, and serum IgM of ST-challenged pigs was greater than controls on d 7 after challenge (P < 0.05). Serum IgG was not affected by enteric disease challenge; however, on d 7 and 14 after disease challenge, serum IgG for both groups was greater (P < 0.05) than on d 0. Dietary QS had no significant influence on any of the end points used to characterize the acute phase response to ST-challenge. Phagocytic cell function was depressed in pigs fed 250 (P < 0.05) and 500 (P < 0.05) mg/kg as compared to pigs fed 125 mg/kg QS. Yet, there was no difference in phagocytic function among pigs fed 0, 250, or 500 mg/kg QS. We conclude that this model of enteric disease invokes an acute phase response accompanied by decreases in feed intake and serum IGF-I. Furthermore, dietary QS, at the levels fed in this study, appears to offer little benefit to growth performance or immune function in the presence or absence of ST-challenge.  相似文献   

2.
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   

3.
Barrows and gilts (n = 100 per gender) were used to determine the effects of an increasing, decreasing, or constant ractopamine (RAC) dietary concentration on growth performance and carcass characteristics. Pigs, within a gender, were assigned randomly to pens (five pigs per pen and 10 pens per treatment). Pens were assigned randomly to one of four dietary treatments at a starting weight of 71.2 kg, to target an average ending weight of 109 kg. The four dietary treatments (as-fed basis) were 1) control = 0 ppm RAC, wk 0 to 6; 2) RAC step-up = 5.0 ppm, wk 1 to 2; 10.0 ppm, wk 3 to 4; and 20.0 ppm, wk 5 to 6; 3) RAC step-down = 20.0 ppm, wk 1 to 2; 10.0 ppm, wk 3 to 4; and 5.0 ppm, wk 5 to 6; and 4) RAC constant = 11.7 ppm, wk 0 to 6. Feed allocation was recorded daily, and pigs were weighed and feed was weighed back every 2 wk. Jugular blood samples were obtained from two randomly selected pigs per pen on d -3, 7, 21, 35, and 41 for determination of plasma urea nitrogen (PUN) concentrations. Two pigs were selected randomly per pen and sent to a commercial slaughter facility at the end of the 6-wk experimental period. Carcass data were evaluated on an equal time basis and on an equal weight basis by using hot carcass weight (HCW) as a covariate. Overall, ADG and G:F were improved (P < 0.05) for pigs fed RAC compared with control, with no differences among RAC feeding programs. In wk 3 and 4, improvements (P < 0.05) in ADG and G:F were realized with the implementation of a RAC step-up program compared with control pigs. The concentrations of PUN were decreased (P < 0.05) at d 7 and 21 with RAC feeding, and a RAC step-up program maintained the decrease (P < 0.05) in PUN through d 35 and 41. A RAC step-up and constant program increased (P < 0.05) HCW and percent yield. Loin muscle area and percentage of fat-free lean increased (P < 0.05) and backfat thickness decreased (P < 0.05) in pigs fed RAC. If pigs were considered to be on feed for an equal time period, advantages (P < 0.05) were observed for weight of boneless trimmed ham, shoulder and loin for the step-up and constant RAC treatments compared with the controls. Feeding a RAC step-up or constant feeding program resulted in favorable responses in growth performance and yielded more lean pork.  相似文献   

4.
A total of 400 barrows from Dekalb EB and 83 terminal sires mated to 43 and 45 maternal lines were used to evaluate the effects of dietary ractopamine (RAC; Paylean, Elanco Animal Health, Greenfield, IN) concentrations (0, 5, 10, or 20 ppm; as-fed basis) and feeding durations (6 to 34 d) on growth, efficiency, carcass, and meat quality characteristics of finishing pigs. Barrows were weighed and sorted into five weight blocks, each block consisting of 16 pens (five pigs per pen). Weight blocks were allocated to feeding duration treatments and assigned consecutively by weight from lightest to heaviest to represent 34, 27, 20, 13, and 6 d on test, respectively. The lightest and heaviest blocks averaged 79.8 and 103.8 kg, respectively, at the start of the test. Within a weight block, pens (four per treatment) were randomly assigned to one of four dietary concentrations of RAC in a basal diet containing 18.5% CP and 1.13% lysine. The experiment-wide target slaughter weight was 109 kg, and pigs and feeders were weighed weekly. Weight blocks (80 barrows per block) were slaughtered at a commercial packing plant after 6, 13, 20, 27, or 34 d on test. Overall, RAC supplementation improved (P < 0.05) ADG; however, ADG was not different (P > 0.08) from controls for pigs fed 5, 10, and 20 ppm RAC for 27, 34, and 6 d, respectively. During each feeding period, RAC-fed pigs had improved (P < 0.05) G:F, and, after 20, 27, and 34 d on test, pigs fed 20 ppm RAC had greater (P < 0.05) G:F compared with those fed 0 or 5 ppm RAC. Hot carcass weight was increased (P < 0.05) by RAC feeding after 13 and 27 d of feeding, and by feeding 10 and 20 ppm RAC after 20 d of feeding. After 34 d, pigs fed 20 ppm RAC had heavier (P < 0.05) hot carcass weight than pigs fed 10 ppm RAC. Fat-free lean estimates and the 10th-rib LM area were increased (P < 0.05) by feeding 10 and 20 ppm RAC after 27 d, and by feeding 20 ppm RAC after 34 d compared with controls. Japanese and American color scores, as well as L*, a*, and b* values of the LM, were not affected (P > 0.11) by 5 and 10 ppm RAC compared with controls during each feeding period. Visual marbling score for the LM was decreased (P < 0.05) when RAC was fed at 10 and 20 ppm compared with 0 ppm RAC when fed for 34 d. Dietary RAC improved growth performance at all feeding durations, whereas carcass composition was improved at longer feeding durations. In addition, 5 and 10 ppm RAC did not affect objective and subjective measures of pork quality.  相似文献   

5.
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   

6.
Our objectives were to investigate and compare the effects of supplemental Mg, Trp, vitamin E (vit E), and vitamin C (vit C) on stress responses of pigs undergoing transport simulation. In this study, 126 pigs (25.1 +/- 4.4 kg BW) were allocated to one of the six following treatments: 1) negative control (no supplementation); 2) positive control (i.m. injection with 0.5 mg of carazolol/20 kg BW 12 h before vibration, beta-blocker); 3) Trp (additional amount of 6 g/kg of feed for 5 d, as-fed basis); 4) Mg (3 g/L drinking water for 2 d); 5) vit E (additional amount of 150 mg/kg of feed for 21 d, as-fed basis); 6) or vit C (additional amount of 300 mg/kg of feed for 21 d, as-fed basis). Pigs were treated in groups of three, and each treatment was replicated seven times. Feed and water intake were not different among treatments. Heart rate variables (mean, peak, and minimum heart rate, ventricular ectopic beats, and ST elevation of Channels A and B) and heart rate variability were registered from the night before vibration. Pigs were subjected to vibration in a transport simulator (8 Hz, 3 m/s) for 2 h and allowed to recover for 2 h. Generally, the positive control pigs had the lowest heart rate values (mean, peak, minimum heart rate, ST elevation of Channel A; P < 0.05), whereas Mg and Trp decreased ventricular ectopic beats and ST elevation of Channel B, respectively. The effect of vit C and E as vagal stimulators was clearly visible, whereas carazolol and Mg clearly blocked the sympathetic pathways of the autonomic nervous system. During vibration, the negative control pigs lay the least, and Mg pigs the most (P < 0.05). Salivary cortisol concentrations (taken before and after vibration and after recovery) showed that vit E pigs produced the least cortisol during stress periods. Intermediary metabolites (glucose, lactate, creatine kinase, and NEFA) were analyzed in plasma from blood taken before and after vibration. At the two sampling points, the vit E and Mg pigs had the lowest NEFA concentrations (P < 0.05), and the vit E pigs also had the lowest lactate concentrations before vibration. Urine samples were collected before and after vibration to determine catecholamine concentrations; only negative control pigs had an increase (P = 0.04) in epinephrine concentration, despite large individual variation. In general, these results indicate that the supplementation of Trp, Mg, vit E, or vit C improved coping ability of pigs during vibration comparison with the negative control treatment. A muscular injection of carazolol influenced only the heart rate variables.  相似文献   

7.
Maternal nutrition and progeny birth weight affect muscle fiber development in the pig, thereby influencing early postnatal growth rate. The objective of the study was to determine the extent to which growth, morphometric characteristics, and area and distribution of slow-oxidative (SO), fast oxidative-glycolytic (FOG), and fast glycolytic (FG) fibers of three muscles (LM = longissimus muscle; RF = rectus femoris; ST = semitendinosus) of slaughter pigs were affected by DE intake level during the first 50 d of gestation. Multiparous Swiss Large White sows were assigned randomly to one of three energy intake treatments: 1) fed 2.8 kg/d of a standard diet (STD; n = 6) containing 10.7 MJ DE/kg; 2) fed 2.8 kg/d of a low-energy diet (LE; n = 5) containing 6.6 MJ DE/kg; or 3) fed 4.0 kg/d of a standard diet (HE; n = 5) containing 10.7 MJ DE/kg (as-fed basis). Sows were subjected to energy intake treatments for the first 50 d of gestation; however, from d 51 to parturition, sows received 2.8 kg/d of the standard diet, and the amount of feed offered each sow during lactation was adjusted according to the litter size. Sows farrowed normally and pig birth weights were recorded. Based on birth weight, the two lightest (1.27 kg; Lt) and two heaviest (1.76 kg; Hvy) barrows and gilts from the 16 litters (n = 64) were selected at weaning and were offered a fixed amount of feed (170 g x BW(0.569)/d) from 25 to 105 kg BW. Regardless of the birth weight, progeny from HE sows grew slower (P < 0.05) during lactation and the growing-finishing period, had a lower (P < 0.05) gain-to-feed ratios, and had higher (P < 0.05) percentages of adipose tissue than pigs born from LE sows. The ST was shorter (P = 0.03) in Lt than in Hvy pigs, and the ST of gilts was heavier (P = 0.01) and had a larger (P = 0.01) girth than the ST of barrows. Overall mean fiber area tended to be larger (P < or = 0.11) in the LM and light portion of the ST of Lt than in Hvy pigs, and was larger (P = 0.03) in the ST of gilts than barrows. The ST of progeny from LE sows had fewer (P < 0.10) FG fibers, which was compensated by either more (P < 0.05) FOG in the light portion of the ST, or more (P < 0.10) SO fibers in the dark portion, and these differences were more pronounced in Lt pigs than in Hvy pigs. Overall, maternal feeding regimen affected muscle fiber type distribution, whereas birth weight and gender affected muscle fiber area.  相似文献   

8.
A disease challenge experiment was conducted to determine if including 10% dried distillers grains with solubles (DDGS) in the diet, with or without antimicrobial supplementation, reduces the incidence or severity, or both, of intestinal lesions in growing pigs after an Lawsonia intracellularis challenge. One hundred 17-d-old weaned pigs were blocked by sex, ancestry, and BW and randomly allotted to 1 of 5 treatment groups: negative control, unchallenged, corn-soy diet; positive control, challenged, corn-soy diet; 10% DDGS diet, challenged; positive control with antimicrobial regimen, challenged; and 10% DDGS diet with antimicrobial regimen, challenged. For antimicrobial-supplemented treatments, diets contained 33 ppm bacitracin methylene disalicylate throughout the experiment, with chlortetracycline (Aureomycin) pulsed at 550 ppm from d 3 prechallenge to d 11 postchallenge. Challenged pigs were orally inoculated with 8.0 x 10(8) L. intracellularis organisms after a 4-wk prechallenge period. On d 21 postchallenge, pigs were euthanized, lesions of intestinal mucosa were evaluated, and ileal tissue samples were analyzed by immunohistochemistry to determine the presence and proliferation rate of L. intracellularis. Compared with other dietary treatments, feeding a diet containing 10% DDGS reduced ileum and colon lesion length and prevalence (P < 0.05) and reduced severity of lesions in the ileum (P < 0.05) and colon (P < 0.10) in challenged pigs. Compared with other challenged pigs, those fed the diet containing the antimicrobial regimen had a lower prevalence and severity of lesions in the jejunum (P < 0.05) and tended to have reduced total tract lesion length (P = 0.11). Compared with other challenged pigs, pigs on the 10% DDGS diet with antimicrobial regimen exhibited no differences in length, severity, or prevalence of lesions (P > 0.15), but fecal shedding of L. intracellularis was reduced on d 14 postchallenge (P < 0.05). No dietary effects on fecal shedding were observed by d 20 postchallenge (P > 0.10). The proportion of cells infected with L. intracellularis was reduced when DDGS (P = 0.05) or antimicrobial (P = 0.10) diets were fed. Under the conditions of this experiment, dietary inclusion of 10% DDGS appears to provide some benefit to growing pigs subjected to a moderate L. intracellularis challenge, similar to those of a currently approved antimicrobial regimen.  相似文献   

9.
Blood acid-base responses to handling were evaluated in slaughter weight pigs fed diets supplemented with l-carnitine and fat. The study was carried out as a randomized block design with a 2 x 2 factorial arrangement of treatments: 1) dietary L-carnitine supplementation (0 vs. 150 ppm, as-fed basis); and 2) dietary fat supplementation (0 vs. 5%, as-fed basis). Sixty pigs (91.1 +/- 5.14 kg BW) were housed in mixed-gender groups of five and had ad libitum access to test diets (0.68% true ileal digestible lysine, 3,340 kcal of ME/kg, as-fed basis) for 3 wk. At the end of the feeding period (110.3 +/- 7.52 kg BW), pigs were subjected to a standard handling procedure, which consisted of moving individual animals through a facility (12.2 m long x 0.91 m wide) for eight laps (up and down the facility), using electric prods (two times per lap). There was no interaction between dietary L-carnitine and fat supplementation for any measurement. Pigs fed 150 ppm of supplemental L-carnitine had lower baseline blood glucose (P < 0.05) and higher baseline blood lactate (P < 0.05) concentrations than the nonsupplemented pigs. After handling, pigs fed L-carnitine-supplemented diets had a higher (P < 0.05) blood pH and showed a smaller (P < 0.05) decrease in blood pH and base excess than those fed the nonsupplemental diets. Baseline plasma FFA concentrations were higher (P < 0.01) in pigs fed the 5% fat diet. After the handling procedure, blood glucose, lactate, and plasma FFA were higher (P < 0.05) in pigs fed the 5 vs. 0% fat diets, but blood pH, bicarbonate, and base excess were not affected by dietary fat. The handling procedure decreased (P < 0.01) blood pH, bicarbonate, base excess, and total carbon dioxide and increased (P < 0.01) blood lactate, partial pressure of oxygen, and glucose, and also increased (P < 0.01) rectal temperature. Free fatty acid concentrations were increased by handling in pigs fed both 0 and 5% fat and 150 ppm L-carnitine. In conclusion, dietary L-carnitine supplementation at the level and for the feeding period evaluated in the current study had a relatively small but positive effect on decreasing blood pH changes in finishing pigs submitted to handling stress; however, dietary fat supplementation had little effect on blood acid-base balance.  相似文献   

10.
Enterotoxigenic E. coli (ETEC) infection and resulting scours is a major problem for young pigs, especially when purified plant proteins are fed rather than spray-dried porcine plasma (SDPP). The effect of supplementing a pea protein isolate (PPI)-based diet with egg yolk antibodies (EYA) from laying hens immunized with ETEC K88 antigen on piglet performance, incidence of scours, and gut histology was studied in a 14-d trial. Ninety-six 10-d-old weaned pigs were assigned to five dietary treatments in a completely randomized design to give six replicate pens per treatment. The treatments were PPI without EYA (PPI-EYA), PPI with EYA (PPI+EYA), SDPP without EYA (SDPP-EYA), SDPP with EYA (SDPP+EYA), or a combination of PPI and SDPP (PPI+SDPP). Diets were formulated to similar nutrient levels and provided for ad libitum intake. Blood from all pigs was taken on d 0, 7, and 14 for determining plasma urea N (PUN). On d 7, pigs were orally challenged with 6 mL of 10(10) cfu/ mL ETEC K88. Piglets were weighed on d 7 and 14. On d 7, 8, and 14, four pigs per treatment were sacrificed to study the histology of the small intestine. Weekly feed intake, BW changes, and gain:feed were determined. Fecal swabs from 10 pigs per treatment were taken for a PCR test to detect K88 E. coli. Feed efficiency over the 14-d period was not affected (P > 0.78) by dietary treatment. Mean ADFI on an as-fed basis was lower (P < 0.002) in piglets fed PPI-EYA (64.3 g/d) compared with PPI+EYA (94.8 g/d) or SDPP (102 g/d) during wk 1. Piglets fed PPI-EYA tend to have a lower (P < 0.026) overall ADG (84 g/d) than those fed PPI+EYA (123 g/d) or SDPP (127 g/d) (P < 0.006)-based diets. Although scours was evident in all groups of pigs 6 h after the challenge, most of the piglets fed EYA- or SDPP-containing diets recovered 10 to 72 h postchallenge, whereas those fed PPI-EYA continued to have severe diarrhea, resulting in 33% mortality. The PCR results showed that a greater (P < 0.01) percentage of piglets fed PPI-EYA compared with those fed SDPP- or EYA-containing diets continued to shed ETEC K88 at the end of the 14-d study. Piglets fed PPI-EYA had shorter villi (P < 0.01), higher intestinal pH (P < 0.013), and higher PUN (P < 0.05) than those fed the SDPP- or EYA-containing diets during the entire 14-d study. It was concluded that specific EYA and SDPP could provide passive control of ETEC infection and potentially improve feed intake and weight gain in young pigs fed PPI.  相似文献   

11.
The effect of feeding diets containing either spray-dried porcine plasma (SDPP) or pea protein-isolate (PPI) supplemented with either egg yolk antibodies (EYA) from hens immunized with enterotoxigenic Escherichia coli (ETEC) (K88 and F18) antigens, ZnO, fumaric acid (FA), or carbadox (AB) on pig performance, incidence of scours, and gut morphology was studied in a 14-d experiment. Ninety 10-d-old weaned pigs were assigned to six dietary treatments in a completely randomized design to give five pens per treatment with three pigs per pen. The diets were SDPP without EYA (SDPP - EYA), PPI without EYA (PPI - EYA), PPI with EYA (PPI + EYA), PPI with ZnO (PPI + ZnO), PPI with FA (PPI + FA), or PPI with AB (PPI + AB). Diets were formulated to similar nutrient levels, with AB, EYA, FA, and ZnO at 0.25, 0.5, 2.0, and 0.4% of the diet, respectively. Pigs were weighed and bled on d 0, 7, and 14 to determine plasma urea N (PUN). Pigs were orally challenged with a 6-mL dose of 10(10) cfu/mL ETEC (K88) on d 7. On d 14, three pigs per treatment were killed to obtain sections of the small intestine for histological measurements. Weekly feed intake, BW changes, and gain:feed were determined. Incidence of scours and scour scores were monitored and fecal swabs were taken before and after ETEC challenge for PCR test to detect ETEC (K88). Feeding SDPP or supplementing PPI-based diets with EYA, ZnO, FA, or AB did not affect (P > 0.05) ADG, ADFI (as-fed basis), or gain:feed throughout the study. However, pigs fed PPI - EYA tended to have lower (P = 0.08) ADFI during wk 2 (137.9 g/d) and lower (P < 0.10) ADG from d 0 to 14 (100.1 g/d) than those fed the SDPP - EYA (156.6 g/d), PPI + EYA (151.2 g/d), PPI + ZnO (158.9 g/ d), PPI + FA (155.4 g/d), and PPI + AB (152.6 g/d) diets. Although scours was evident in all pigs 8 h after the ETEC challenge, it lasted only 3 to 5 d in pigs fed SDPP or PPI supplemented with EYA, ZnO, FA, or AB. Pigs fed PPI - EYA continued to have severe diarrhea, resulting in 40% mortality vs. 13% or less in the other groups. The PCR results showed that 81% of PPI-fed pigs continued to shed ETEC K88 7 d after ETEC challenge. Pigs fed PPI-EYA had shorter villi (P < 0.05), reduced villi:crypt ratio (P < 0.003), and higher intestinal pH (P < 0.001) and PUN (P < 0.001) than those fed SDPP or PPI supplemented with EYA, ZnO, FA, and AB. In conclusion, SDPP, EYA, ZnO, FA, and AB may have provided passive control to ETEC (K88) infection and potentially enabled young pigs to efficiently utilize a PPI-based diet.  相似文献   

12.
Forty-eight barrows and forty-eight gilts (PIC 337 sires x PIC C22 dams) were evaluated to determine the effects of feeding ractopamine hydrochloride (RAC) and different cereal grains on the carcass and fat quality in late finishing pigs. The study was carried out using four replicates with 24 animals in each replicate (four pigs per pen, six pens per replicate, two replicates per slaughter date, 12 pens per slaughter date). Treatments for the experiment included corn, wheat, and barley (early finisher period); and corn, corn + RAC, wheat, wheat + RAC, barley, and barley + RAC for the late finisher period. Ractopamine was fed at the level of 10 mg/kg (as-fed basis) of feed. Pigs were allotted to early finisher period treatments at approximately 45 kg BW. Pigs were then given late finisher period treatments at approximately 80 kg BW and fed for 28 d. The dietary digestible lysine level for all diets was maintained at 2.7 g/Mcal of ME. Pigs fed the wheat and corn diets during the late finisher period had a greater (P <0.05) G:F than those fed the barley diets. Pigs fed diets with RAC had lower (P <0.05) leaf fat weights, 10th-rib fat, last-rib fat, and belly firmness and had improved (P <0.05) dressing percents and loin muscle areas compared with those not receiving RAC. Pigs fed the wheat diets had a greater (P <0.05) dressing percent than those receiving the barley diets, but pigs fed the barley diets had a higher (P <0.05) Minolta L* for fat color than pigs fed wheat. Pigs fed diets containing RAC produced pork that was less tender (P <0.05) compared with pigs that did not receive RAC. Linoleic acid percent values were higher (P <0.05) for pigs fed diets with RAC than in those that did not. Feeding RAC improved G:F and lowered feed intake of pigs during the late finisher period (P <0.05). Feeding diets equal in lysine (2.7 g/Mcal of ME) but varying in ME, whether based on corn, wheat, or barley with or without RAC, had little to no effect on carcass, meat, or fat quality attributes.  相似文献   

13.
A total of 108 crossbred piglets (7.75 +/- 0.24 kg of BW) weaned at 28 d was used to study the interactive effects of beta-glucan obtained from the Chinese herb Astragalus membranaceus (AM) and Escherichia coli lipopolysaccharide (LPS) challenge on performance, immunological, adrenal, and somatotropic responses of weaned pigs. The treatments were in a 2 x 3 factorial arrangement; main effects were level of Astragalus membranaceus glucan (AMG; 0, 500, or 1,000 mg/kg; as-fed basis) and presence of immunological challenge (with or without LPS). The experiment included six replicate pens per treatment and three pigs per pen. Lipopolysaccharide challenges were conducted on d 7 and 21 of the trial. Blood samples were obtained from the vena cava from one pig per pen at 3 h after LPS challenge to determine plasma responses. Weight gain and feed:gain ratio were unaffected by glucan. However, there was a quadratic effect on feed intake (P < 0.05): pigs fed 500 mg of glucan/kg had the highest feed intake. Immunological challenge with LPS decreased weight gain (P = 0.02). An interaction (P = 0.01 to 0.09) between AMG and LPS was observed for glucose, IL-1beta, PGE2, and cortisol. Astragalus membranaceus glucan had a quadratic effect on the plasma concentrations of glucose, IL-1beta, PGE2, and cortisol (P < 0.05) after both LPS challenges. Plasma concentrations of glucose, IL-1beta, PGE2, and cortisol (P < 0.05) were all increased in LPS-challenged pigs compared with the control pigs after both LPS challenges. The IGF-I concentrations were less for LPS-challenged pigs than for unchallenged pigs. The lymphocyte proliferation response of peripheral blood induced by 5 microg of concanavalin A/mL (P < 0.01) and IL-2 bioactivity (P < 0.05) increased linearly with increasing addition of glucan. Pigs challenged with LPS had greater T-lymphocyte proliferation (P = 0.06) and IL-2 bioactivity (P = 0.07) than unchallenged pigs after the first immunological challenge but not after the second. In conclusion, although glucan did not improve pig performance under the conditions of the present experiment, when included at 500 mg/kg, it decreased the release of inflammatory cytokine and corticosteroid and improved the lymphocyte proliferation response of weanling piglets via enhanced IL-2 bioactivity.  相似文献   

14.
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   

15.
The objective of this study was to determine whether dietary quillaja saponin and curcumin (extract of turmeric) can modify piglet immune status and performance immediately after weaning. Piglets (n = 192) were weaned at 29 +/- 0.1 d and allocated to treatment (six replicates of eight pig per treatment) accounting for weight, litter, and gender, using a 2 x 2 factorial arrangement. Factors were diets with or without (as-fed basis) quillaja saponin (750 mg/kg during wk 1, 300 mg/kg during wk 2 to 3) and with or without dietary curcumin (200 mg/kg). Diets were fed ad libitum for 20 d after weaning. Feed intake was measured daily. Piglets were weighed at weaning, d 7, 14, and 20 after weaning. On each of d 6 and 20 after weaning, eight pigs per treatment were sacrificed for blood and tissue collection. Treatment had no effect on piglet growth. The ADFI and G:F were similar for all treatments between d 0 and 14 of the trial. Between d 15 and 20, ADFI and G:F were lower in quillaja-supplemented piglets (ADFI = 621 vs. 572 g/d; G:F = 0.75 vs. 0.85; P < 0.05). Serum immunoglobulin (Ig) G, IgA, interferon-gamma, and C-reactive protein (CRP) did not differ among treatments on d 6 after weaning. On d 20, IgG and CRP were greater (P < 0.05) in saponin-supplemented pigs (IgG = 17.5 vs. 11.4 mg/mL; CRP = 26.98 vs. 12.5 mg/mL). Small intestine villus and crypt measurements did not differ among treatments on either d 6 or 20. Saponin supplementation during the postweaning period seemed to potentiate an immune response in the weaned piglet but had a detrimental effect on the utilization of feed. Dietary curcumin had no influence on any measured aspect of pig performance or immune status.  相似文献   

16.
To test possible dietary immune modulators, 32 crossbred male pigs were given 1 of 4 dietary treatments (8 pigs/treatment): control, Saccharomyces cerevisiae with beta-glucan (Energy Plus, Natural Chem Industries LTD, Houston, TX; 0.312 g/kg of BW, 2.5% of diet), vitamin C (Stay C 35, DSM Nutritional Products Inc., Prisippany, NJ; 75 ppm), or beta-glucan plus vitamin C together (combination; 0.312 g/kg of BW and 75 ppm, respectively). Supplements were given in whole milk within 36 h of birth and then daily for 2 wk until weaning, when the supplement was given in feed for an additional 2 wk. Growth was recorded during the 4 wk of supplement delivery. An i.v. lipopolysaccharide challenge (LPS; 150 microg/kg) was given 14 d postweaning at 0900. Behavior was observed, and blood samples were collected every 30 min for 4 h via a jugular catheter from -1 (0800) to 3 (1200) h relative to challenge (-60, -30, 0, 30, 60, 90, 120, 150, and 180 min), and tissues were collected after exsanguination. Beta-glucan (glucan and combination) increased (P < 0.05) BW and ADG compared with vitamin C and control. Cortisol concentrations showed an interaction (P < 0.05) of the beta-glucan and vitamin C. Intestinal expression of tumor-necrosis factor (TNF)-alpha mRNA was greatest for vitamin C and beta-glucan compared with control and combination, and liver TNF-alpha mRNA expression showed a main effect (P < 0.01) of beta-glucan. Lung expression of TNF-alpha mRNA exhibited a vitamin C effect (P < 0.01). In contrast, spleen had greater (P < 0.01) relative abundance of TNF-alpha mRNA in beta-glucan pigs. Intestinal expression of IL-1Ra mRNA was greater (P < 0.05) for vitamin C and beta-glucan treatments compared with the control and combination pigs. Liver expression of IL-1 receptor antagonist mRNA exhibited a vitamin C effect (P < 0.01). Lying and sleeping behaviors differed (P < 0.05) among treatments early in the observations (0700 to 0720), then sporadically until 50 min after the LPS injection. The vitamin C group slept less (P < 0.05) on those occasions. The time spent lying was least (P < 0.05) for the glucan and combination pigs immediately after the injection. These results show a complex interaction between vitamin C and this yeast product after LPS challenge, with differential expression in tissues by 2 h after LPS injections. The combination enhanced postweaning growth and reduced TNF-alpha expression of the intestinal and liver tissues, suggesting an important immunomodulatory role of the combination treatment.  相似文献   

17.
Four experiments involving 1,005 crossbred pigs weaned at 19 +/- 2 d of age evaluated the effect of diet complexity and lactose level on starter pig performances. Experiment 1 was a randomized complete block (RCB) conducted in nine replicates with 135 pigs. A complex diet using several protein sources, a semicomplex diet with fewer protein sources, and a simple diet of corn and soybean meal comprised the three treatment groups. All diets contained 25% lactose (as-fed basis) with lysine (total) constant from d 0 to 14 (1.55%) and d 14 to 28 (1.45%), respectively. Gain, feed intake, and feed efficiency (P < 0.05) improved as diet complexity increased during both periods. In Exp. 2, 240 pigs in eight replicates in a RCB design were fed complex diets, but dietary lactose (total; as-fed basis) levels ranged from 10 to 35% in 5% increments from 0 to 14 d after weaning. From 14 to 30 d, a common 17% lactose diet was fed to evaluate the effects of early lactose level on subsequent responses. Gains (P < 0.05) increased for the 0- to 7- and 0- to 14-d periods as lactose increased to 30%. Similar gains resulted for all treatment groups from 14 to 30 d after weaning, with no evidence of compensatory responses to early lactose levels. In Exp. 3, 330 pigs were fed complex diets. From 0 to 7 d after weaning, the diets contained 25% lactose (as-fed basis), and from 7 to 21 d postweaning, the lactose levels ranged from 7 to 31% in 5% increments. Gain (P < 0.01) and feed efficiency (P < 0.05) increased from 7 to 21 d to the 17% lactose level. In Exp. 4, 300 pigs were fed 25 and 17% (as-fed basis) lactose diets from 0 to 7 and 7 to 21 d postweaning, respectively. From 21 to 35 d postweaning, lactose levels of 0 to 20% in 5% increments were added to a corn-soybean meal diet. The experiment was conducted as a RCB design in 12 replicates. Gain (P < 0.05) and feed intake (P < 0.05) increased to 10 to 15% lactose. When the data from Exp. 4 were partitioned into lighter (15.0 kg) and heavier (17.7 kg) pig weight replicates, only the lighter replicates had significant improvements in gain, feed intake, and feed efficiency (P < 0.05) in response to dietary lactose. These results demonstrated that starter pigs performed better when fed complex diets, that dietary lactose levels of 25 to 30% (to 7 kg BW) during the initial week postweaning, 15 to 20% lactose during d 7 to 21 (to 12.5 kg BW), and 10 to 15% lactose during d 21 to 35 postweaning (to 25 kg BW) resulted in maximum performance.  相似文献   

18.
Three hundred sixteen crossbred pigs were used in two experiments to determine the effect of supplemental manganese source and dietary inclusion level during the growing-finishing period on performance and pork carcass characteristics. All pigs were blocked by weight, and treatments were assigned randomly to pens within blocks. In Exp. 1, a total of 20 pens (five pigs/pen) was randomly assigned to one of five dietary treatments consisting of control grower and finisher diets, or control diets supplemented with either 350 or 700 ppm (as-fed basis) Mn either from MnSO4 or a Mn AA complex (MnAA). In Exp. 2, a total of 36 pens (six pigs per pen) was assigned randomly to one of six dietary treatments formulated with 0, 20, 40, 80, 160, or 320 ppm (as-fed basis) Mn from MnAA. Pigs were slaughtered when the lightest block averaged 120.0 kg (Exp. 1) or at a mean BW of 106.8 kg (Exp. 2). Neither ADG nor ADFI was affected (P > 0.21) by Mn source or high inclusion level (Exp. 1); however, across the entire feeding trial, pigs consuming 320 ppm Mn from MnAA were more (P < 0.04) efficient than pigs fed diets formulated with 20 to 160 ppm Mn from MnAA (Exp. 2). Color scores did not differ (P > 0.79) at the low inclusion (20 to 320 ppm Mn) levels used in Exp. 2; however, in Exp. 1, the LM from pigs fed Mn tended to receive higher (P = 0.10) American color scores than that of pigs fed the control diet, and Japanese color scores were higher for the LM from pigs fed diets containing 350 ppm Mn from MnAA than 350 Mn from ppm MnSO4 or 700 ppm Mn from MnAA (source x inclusion level; P = 0.04; Exp. 2). Chops of pigs fed 350 ppm Mn from MnAA were darker than the LM of pigs fed 350 ppm Mn from MnSO4, and 700 ppm Mn from MnAA diets (source x inclusion level; P = 0.03; Exp. 1), but L* values were not (P = 0.76) affected by lower MnAA inclusion levels (Exp. 2). Even though the LM tended to became redder as dietary MnAA inclusion level increased from 20 to 320 ppm Mn (linear effect; P < 0.10), a* values were not (P = 0.71) altered by including 350 or 700 ppm Mn (Exp. 1). Chops of pigs fed MnAA had lower cooking losses (P = 0.01) and shear force values (P = 0.07) after 2 d of aging than did chops from pigs fed diets formulated with MnSO4. Results from these experiments indicate that feeding 320 to 350 ppm Mn from MnAA during the growing-finishing period may enhance pork quality without adversely affecting pig performance or carcass composition.  相似文献   

19.
Feeding increased levels of dietary vitamin E can inhibit lipid oxidation. The aim of this study was to investigate the effect of levels of dietary alpha-tocopherol acetate (VE) and feeding duration on meat quality and lipid oxidation. Eighty-one pigs were allocated to 1 of 3 diets containing 40, 200, or 400 IU of VE/kg of feed, and each diet group was divided into 3 feeding periods (3, 6, or 9 wk). Carcass characteristics and meat quality were evaluated. Oxidative stability of fresh and cooked pork patties and pork chops was determined after chilled or frozen storage. Increasing dietary concentrations of VE did not affect any growth performance parameter. Drip loss, however, decreased (P < 0.05) with increased dietary VE levels. Moreover, an increased duration of VE feeding improved (P < 0.05) pH and drip loss. Less lipid oxidation (P < 0.05) was detected in fresh ground pork from pigs fed greater concentrations of VE after 4 d of storage. A greater (P < 0.05) resistance to oxidation in cooked ground pork was observed in pigs fed 200 or 400 IU of VE/kg at 2 and 6 d of storage. Fresh and cooked pork patty oxidation decreased (P < 0.05) linearly as feeding duration increased from 3 to 9 wk. After 6 mo of freezer storage, lipid oxidation of pork chops from pigs fed 200 or 400 IU of VE/kg was lower (P < 0.05) than for pigs fed 40 IU of VE/kg. Likewise, lipid oxidation of pork chops of pigs fed VE for an extended period of time (6 wk) was lower (P < 0.05) after 9 mo of storage. Fatty acid profiles of neutral lipid fraction of the LM became more unsaturated (P < 0.05) with added VE to the feed. These results indicate an increased intake of dietary VE concentration, and prolonged feeding of VE can improve drip loss and reduce lipid oxidation in ground pork and pork chops. This study suggests that supplementation with 200 IU of VE/kg of feed for 6 wk before market is beneficial in improving lipid stability and pork quality.  相似文献   

20.
Benefits of feeding pharmacological concentrations of zinc (Zn) provided by Zn oxide (ZnO) to 21-d conventionally weaned pigs in the nursery have been documented; however, several management questions remain. We conducted two experiments to evaluate the effect on growth from feeding 3,000 ppm Zn as ZnO during different weeks of the nursery period. In Exp. 1 (n = 138, 11.5 d of age, 3.8 kg BW) and Exp. 2 (n = 246, 24.5 d of age, 7.2 kg BW), pigs were fed either basal diets containing 100 ppm supplemental Zn (adequate) or the same diet with an additional 3,000 ppm Zn (high) supplied as ZnO. Pigs were fed four or two dietary phases in Exp. 1 and 2, respectively, that changed in dietary ingredients and nutrient content (lysine and crude protein) to meet the changing physiological needs of the pigs for the 28-d nursery period. Dietary Zn treatments were 1) adequate Zn fed wk 1 to 4, 2) high Zn fed wk 1, 3) high Zn fed wk 2, 4) high Zn fed wk 1 and 2, 5) high Zn fed wk 2 and 3, and 6) high Zn fed wk 1 to 4. In Exp. 1 and 2, pigs fed high Zn for wk 1 and 2 or the entire 28-d nursery period had the greatest (P < .05) ADG. During any week, pigs fed high Zn had greater concentrations of hepatic metallothionein and Zn in plasma, liver, and kidney than those pigs fed adequate Zn (P < .05). In summary, both early- and traditionally weaned pigs need to be fed pharmacological concentrations of Zn provided as ZnO for a minimum of 2 wk immediately after weaning to enhance growth.  相似文献   

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