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1.
The serum enzymes of pigs naturally infected with the metacestodes of Taenia solium and of uninfected pigs were assayed. Aspartate aminotransferase, alanine aminotransferase, ornithine carbamyl transferase, sorbitol dehydrogenase, lactate dehydrogenase, isocitrate dehydrogenase, alkaline phosphatase and ceruloplasmin activities were significantly increased in the serum of the infected pigs.  相似文献   

2.
The serum enzymes of pigs naturally infected with the metacestodes ofTaenia solium and of uninfected pigs were assayed. Aspartate aminotransferase, alanine aminotransferase, ornithine carbamyl transferase, sorbitol dehydrogenase, lactate dehydrogenase, isocitrate dehydrogenase, alkaline phosphatase and ceruloplasmin activities were significantly increase in the serum of the infected pigs.  相似文献   

3.
The aim of this investigation was to study the effect of K-diformate on the intraluminal pH, microbial composition in digesta and feces, organic acids along the digestive tract, and alterations of the gastric epithelium of pigs. Pigs (n = 36) weaned at 28 d of age were allotted to two groups and fed without (control diet) or with 1.8% supplemental K-diformate. Fecal samples were taken from the rectum on d 0, 1, 3, 5, 7, 14, 21, and 28 postweaning. Half of the animals from each group were killed on d 7 and the other half on d 29 postweaning. Growth performance was not different for both groups (P > or = 0.73). The gastric epithelium was not negatively affected by K-diformate (P = 0.25). Potassium-diformate decreased (P < or = 0.04) or tended to decrease (P < or = 0.10) the counts of total anaerobic bacteria, lactic acid bacteria, and yeasts in feces and digesta samples from the stomach, distal small intestine, cecum, and middle segment of the colon. The pH along the gastrointestinal tract of piglets was not affected by K-diformate (P > or = 0.30). On d 7, the concentration of lactic acid along the gastrointestinal tract was similar with both diets (P = 0.15). On d 29, the concentrations of lactic acid tended to be lower along the small intestine (P < or = 0.08) and the stomach (P = 0.11) of the pigs fed K-diformate. Formic acid in digesta was detected at significant levels only in the distal segment of the small intestine of the control pigs (from 4 to 11 mmol/kg of wet digesta), whereas considerable amounts were measured in the stomach (from 23 to 40 mmol/kg of wet digesta) and all segments of the small intestine (from 7 to 25 mmol/kg of wet digesta) in the K-diformate-fed pigs on both days. On d 7, pigs fed the K-diformate diet had a tendency (P < or = 0.08) to have higher concentrations of organic acids (acetic + propionic + butyric) in the digesta of the distal small intestine, cecum, and proximal colon. On d 29, both groups had similar concentrations of these acids, irrespective of the segment of the gastrointestinal tract (P = 0.95). Our study showed that the addition of K-diformate to a starter diet for piglets decreased total anaerobic bacteria, lactic acid bacteria, coliforms, and yeasts in feces and in digesta from various segments of the gastrointestinal tract, without affecting the gastric or intestinal pH.  相似文献   

4.
The present study gives an overview on the whole mechanism of phytate degradation in the gut and the enzymes involved. Based on the similarity of the human and pigs gut, the study was carried out in pigs as model for humans. To differentiate between intrinsic feed phytases and endogenous phytases hydrolysing phytate in the gut, two diets, one high (control diet) and the other one very low in intrinsic feed phytases (phytase inactivated diet) were applied. In the chyme of stomach, small intestine and colon inositol phosphate isomers and activities of phytases and alkaline phosphatases were determined. In parallel total tract phytate degradation and apparent phosphorus digestibility were assessed. In the stomach chyme of pigs fed the control diet, comparable high phytase activity and strong phytate degradation were observed. The predominant phytate hydrolysis products were inositol phosphates, typically formed by plant phytases. For the phytase inactivated diet, comparable very low phytase activity and almost no phytate degradation in the stomach were determined. In the small intestine and colon, high activity of alkaline phosphatases and low activity of phytases were observed, irrespective of the diet fed. In the colon, stronger phytate degradation for the phytase inactivated diet than for the control diet was detected. Phytate degradation throughout the whole gut was nearly complete and very similar for both diets while the apparent availability of total phosphorus was significantly higher for the pigs fed the control diet than the phytase inactivated diet. The pathway of inositol phosphate hydrolysis in the gut has been elucidated.  相似文献   

5.
A 2 x 2 factorial experiment with pigs was undertaken to investigate the effect of particle size (fine and coarse) and feed processing (pelleted and nonpelleted) on morphological characteristics in the small intestine, cecum, and colon of pigs and on the adhesion of Salmonella enterica serovar Typhimurium DT12 to the ileum in vitro. Ninety-six pigs (average BW = 33 +/- 7 kg) were fed the experimental diets. After 4 wk, 24 pigs were selected (six pigs per diet) and euthanized, and tissue samples were taken from the mid and distal small intestine, cecum, and distal colon. The effects of particle size and feed processing on villus height and crypt depth in the small intestine were minor. Feeding coarse diets increased (P = 0.05) the crypt depth in the colon. The crypt depth was 420 +/- 12 and 449 +/- 12 microm in pigs fed finely and coarsely ground feed, respectively. Pigs fed pelleted diets had a larger (P = 0.01) staining area for neutral mucins, as well as for acidic and sulfomucins on the villi of the distal small intestine than pigs fed nonpelleted diets. The area was 41, 46, and 33% larger for neutral, acidic, and sulfomucins, respectively. The mucin-staining areas of the crypts in the cecum and the colon were not affected by the experimental diets. Examination of lectin binding characteristics of the distal small intestine and the cecum did not reveal any differences between the experimental diets. Using a pig intestine organ culture model, Salmonella adhered less (P < 0.05) to the ileal tissue of pigs fed the nonpelleted diets than to those fed pelleted diets; the adherence was 60% less in these pigs. Results of this study suggest that pigs fed pelleted diets secrete mucins that are capable of binding Salmonella enterica serovar Typhimurium DT12 and thereby allowing for colonization. Therefore, pigs fed a nonpelleted diet are better protected against Salmonella infections than pigs fed a pelleted diet.  相似文献   

6.
Concentrations of amines were analysed in the digesta of piglets and fattening pigs after refining using an aminoacid-analyser. Feed contained only small amounts of putrescine. In the stomach histamine, tyramine, putrescine and cadaverine were nearly equally distributed, whereas in the colon cadaverine presented the main part. Piglets with 24% CP had in stomach/small intestine/hindgut 4.2/10.2/9.6 mmol, with 18% CP-/5.5/4.9 mmol amines/kg DM digesta. Fattering pigs showed in jejunal digesta from 2.1 to 8.7 mmol, in the caecum 1 to 4.8 mmol and in the colon 0.2 to 2.2 mmol amines/kg DM. Increasing CF-contents and bactericide supplements in the diet lowered amine concentration in all gut sections not significantly.  相似文献   

7.
The effect of feeding a coarsely ground meal (COARSE) and a finely ground pelleted diet with 1.8% (as-fed basis) added formic acid (ACID) was compared with feeding a standard finely ground pelleted diet (STD) on the gastrointestinal ecology of growing pigs at different intervals after feeding. One hundred five castrated male growing-finishing pigs (initial BW 27 kg) were used. At a BW of 63 kg, 60 pigs were killed 0.5, 2.5, 4.5, 6.5, and 8.5 h after feeding, and samples from the gastrointestinal tract (GIT) were obtained. The remaining 45 pigs were kept on the experimental diets to a BW of 99 kg. Feeding the three diets resulted in a similar pattern of gastric pH with time, (i.e., highest pH values 0.5 h after feeding and decreasing values at the following sampling times, to reach a value of 2.12 at 8.5 h after feeding). The pH of the gastric digesta of pigs fed the ACID diet was below 4 at all sampling times, whereas the digesta from the other two dietary groups had values above pH 4 at the first sampling times. Feeding the ACID diet decreased the counts of total anaerobes in the proximal GIT (P < or = 0.007), and of lactic acid bacteria (P < or = 0.001), enterobacteria (P < or = 0.02), and yeasts (P < or = 0.01) along the GIT compared with feeding the other two diets. Feeding the COARSE diet stimulated the growth of total anaerobes and lactic acid bacteria in the stomach and distal small intestine increased the microbial diversity mainly in the stomach (P = 0.001), compared with feeding the other two diets (P < or = 0.09), and decreased the number of enterobacteria in the cecum compared with the STD diet (P = 0.03), with the same tendency in the mid-colon (P = 0.07). The concentration of lactic acid in the stomach was highest in the pigs fed the COARSE diet compared with the other two groups (P < 0.05). The concentration of formic acid was highest in the stomach and all segments of the small intestine of the pigs fed the ACID diet compared with those fed the STD and COARSE diets (P < 0.05). The results from this study suggest that feeding a coarsely ground diet and a finely ground diet with added formic acid affect the gastrointestinal ecology of pigs mainly by changing the environment in the proximal GIT. The presence of organic acids in the proximal GIT is a crucial factor contributing to the decrease in the number of enterobacteria along the GIT. The time after feeding at which samples are taken to measure characteristics describing the gastrointestinal ecology affects the results from the stomach and small intestine.  相似文献   

8.
Corn containing genetically engineered plasmid DNA encoding an Escherichia coli glutamate dehydrogenase (gdhA) was fed to 19-d-old weanling swine to trace the digestive fate of the transgenic DNA. Eight pens of 8 pigs were fed a commercial (nongdhA) starter for 2 wk. One pig was randomly selected from each pen for 0-h control samples. The remaining 56 pigs were transitioned onto a corn-soybean meal diet and fed a diet containing 58% gdhA corn for approximately 1 wk; immediately thereafter, liver, 10th rib muscle, white blood cells, and plasma from the hepatic portal vein and ingesta from the stomach, distal ileum, and large intestine were collected. The DNA was extracted and the concentration determined via spectrophotometry. Polymerase chain reaction and gel electrophoresis were performed with primers designed to amplify 490 bp that included the plasmid's ligation site between the maize ubiquitin and the gdhA genes. The gdhA corn-derived DNA and diet served as positive assay controls, and conventional corn DNA and distilled water acted as negative assay controls. Detection limits were 0.99 fg of target DNA confounded with 500 ng of conventional corn DNA per each 20 &L reaction. Transgenic DNA was detected in 71.43% of the stomach and 1.79% of the ileal ingesta samples from treatment animals but was not detected in the large intestine, white blood cells, plasma, liver, or muscle samples. Transgenic DNA was not detected in any sample from 0-h control animals. Stomach and ileal ingesta samples were further analyzed using real-time PCR. With an estimated limit of detection of 1.049 ag/microL, 89.29% of the stomach ingesta samples were positive (average 1.56 fg target DNA). The proportion of transgenic DNA to total DNA differed between diet and stomach ingesta samples (P < 0.001). Despite the greater sensitivity of real-time PCR, target DNA was detected in only 1.79% of ileal ingesta. These data suggest that the gdhA transgene began degradation in the stomach and was nondetectable in the large intestine.  相似文献   

9.
Thirty-two crossbred barrows were used to investigate the effects of dietary Ca:total P (tP) ratios in phytase-supplemented diets on the apparent absorption of P and Ca in the small intestine, cecum, and colon. Three Ca:tP ratio treatments (1.5:1, 1.3:1, or 1.0:1) were created by adjusting the amount of ground limestone added to the basal low-P grower (.39% tP including .07% added inorganic P) and finisher (.32% tP without added inorganic P) diets. All low-P ratio diets were supplemented with Natuphos phytase at 500 units/kg. A positive control diet without phytase supplementation contained adequate P and Ca to meet dietary requirements. At 123 kg, the pigs were slaughtered and the contents of ileum, cecum, and colon were collected. Lowering the dietary Ca:tP ratio in the diets containing phytase linearly increased (P < .01) the apparent absorption (% and g/d) of P in the small intestine, but Ca absorption was not affected. Pigs fed the low-P diet with a Ca:tP ratio of 1.0:1 had an apparent absorption (g/d) of P or Ca similar to that of pigs fed the control diet, which was adequate in Ca and P. Averaged across all diets, the apparent absorption of P was highest when measured at the cecum, and the apparent absorption of Ca was highest when measured at the colon. In conclusion, lowering the dietary Ca:tP ratio to 1.0:1 in a low-P diet containing phytase increased the apparent absorption of P in the small intestine. Furthermore, a significant amount of P was absorbed in the cecum.  相似文献   

10.
The effects of adding a multienzyme complex to a diet containing distillers dried grains with solubles (DDGS) produced from a 1:1 mixture of corn and wheat on visceral organ weight, intestinal morphology, and fasting whole-body oxygen consumption (FWBOC) were investigated in growing pigs in a 28-d trial. Twenty-four pigs (BW = 19.9 ± 0.5 kg) were individually housed in floor pens and randomly assigned to 3 experimental diets (8 pigs per diet). The diets contained corn and soybean meal with 0% (control) or 30% DDGS (DDGS diet); the third diet was supplemented with a multienzyme complex in addition to the 30% DDGS (DDGS + enzyme diet). All diets had similar nutrient concentrations and met the 1998 NRC nutrient requirements for growing pigs. Pigs were fed at 4% of their BW once daily. On d 15, 4 pigs from each dietary treatment were randomly selected for measurement of FWBOC during the 24- to 30-h postprandial period using an open-circuit indirect calorimeter. At the end of the study, pigs were killed to determine visceral organ weights, ileal and cecal digesta viscosity, and intestinal morphology. There was no effect (P > 0.05) of dietary treatment on final BW, WBFOC, or digesta viscosity. Empty BW of pigs fed the control diet was heavier (P = 0.02) than that of pigs fed the DDGS diet, but the empty BW of pigs fed the DDGS + enzyme diet was not different (P > 0.05) from that of pigs fed the control or DDGS diet. There were no differences (P > 0.05) in empty BW of liver, spleen, pancreas, heart, stomach, small intestine, and cecum among dietary treatments on a per kilogram basis. However, pigs fed the DDGS diet had heavier (P < 0.05) colon plus rectum and portal-drained viscera (PDV) than pigs fed the control diet, but weights of colon plus rectum and PDV in pigs fed the DDGS + enzyme diet were not different (P > 0.05) from those of pigs fed the control diet. Although morphological data showed no differences (P > 0.05) in the duodenum, jejunum, and colon segments among dietary treatments, the DDGS diet tended to decrease (P < 0.10) villous height and villous height to crypt depth in the ileum. The results of this experiment indicated that pigs fed a diet containing 30% DDGS have reduced dressing percentage and increased visceral organ mass compared with pigs fed a corn-soybean meal diet. However, the addition of a multienzyme complex to the DDGS diet resulted in pigs having a dressing percentage and visceral organ mass that are not different from those of pigs fed a corn-soybean meal diet.  相似文献   

11.
Lactate, formed mainly in the stomach and small intestines, and short-chain fatty acids (SCFAs) formed in the colon, are ionised and require transporter proteins such as monocarboxylate transporters (MCTs) for absorption. The amounts of MCT1, MCT2, MCT4 and CD147, an ancillary protein for MCT1 and MCT4, were measured by immunoblotting the small intestine and colon of 40 pigs (Landrace, Yorkshire and LandracexYorkshire). MCT1 and MCT4 were found in both small intestine and colon, but MCT2 only in the small intestine. In both small intestine and colon, Yorkshire pigs had more CD147 than Landrace pigs, while no interbreed differences were found in MCT isoforms. Since CD147 is essential for the activity of MCT1 and MCT4, the breed difference suggests that MCT activity is higher in Yorkshire than in Landrace pigs. The absence of MCT2 in the colon suggests that it is mainly a lactate transporter, while MCT1 and MCT4 facilitate the transport of both lactate and SCFA.  相似文献   

12.
本试验旨在研究谷氨酸(Glu)对脂多糖(LPS)刺激断奶仔猪肠道能量代谢的影响。选择24头断奶仔猪分为4个组,分别为对照组、LPS组、LPS+1.0%Glu组和LPS+2.0%Glu组,每组6个重复,每个重复1头猪。于试验第28天,试验组猪注射100μg/kg BW LPS,对照组注射等量的生理盐水,4 h后屠宰,取肠道样品待测。结果表明:1)与对照组相比,LPS刺激导致断奶仔猪空肠三磷酸腺苷(ATP)、腺苷酸池(TAN)含量和能荷(EC)显著降低(P0.05),一磷酸腺苷(AMP)/ATP值显著升高(P0.05);与LPS组相比,LPS+2.0%Glu组显著提高了空肠ATP、二磷酸腺苷(ADP)和TAN含量(P0.05)。2)与对照组相比,LPS刺激导致断奶仔猪回肠柠檬酸合成酶和α-酮戊二酸脱氢酶系活性极显著降低(P0.01),空肠α-酮戊二酸脱氢酶系活性有降低趋势(P=0.092);与LPS组相比,除LPS+1.0%Glu组回肠柠檬酸合成酶活性显著降低(P0.05)外,Glu对空肠和回肠三羧酸循环关键酶活性无显著影响(P0.05)。3)与对照组相比,LPS刺激导致空肠过氧化物酶体增殖物激活受体γ辅激活因子1α(PGC1α)及回肠沉默信号调控因子1(Sirt1)和PGC1α的mRNA表达量极显著降低(P0.01);与LPS组相比,LPS+2.0%Glu组有提高空肠PGC1α(P=0.067)和回肠Sirt1(P=0.053)mRNA表达量的趋势,LPS+1.0%Glu组有提高回肠Sirt1 mRNA表达量的趋势(P=0.070)。由此可见,Glu可以改善LPS刺激导致的肠道能量损耗状态。  相似文献   

13.
14.
A study was made of blood cellular components, serum proteins and serum enzymes in 48 pigs naturally infected with Cysticercus tenuicollis. Twenty-five healthy pigs were studied for comparison. Affected animals showed a reduction in total erythrocyte count, packed cell volume and haemoglobin content and an increase in mean corpuscular volume and total leucocyte count. Significantly higher activities of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase and isocitric dehydrogenase serum enzymes were recorded in all affected pigs. Total protein, albumin and globulin values of affected pigs remained unchanged when compared with healthy controls.  相似文献   

15.
Effects of age and diet composition on amylase, trypsin and chymotrypsin activities in the pancreas and intestinal contents, pancreas weights and body weights were determined from birth to 56 d. A total of 120 pigs, five to seven pigs/litter from 18 litters, were slaughtered at birth, 14, 27, 29, 31, 42 and 56 d. Litters were allotted to dietary treatments (corn-soy, A; corn-soy + 20% dried whey, B; corn-soy + 5% lard, C) and offered these diets as creep feed at 14 d. All pigs were weaned at 28 d, placed in elevated nursery pens and fed their respective diets. Total activities of amylase, trypsin and chymotrypsin in the pancreas and small intestine increased (P less than .05) with age. Both trypsin and amylase activities, measured per kilogram body weight or gram pancreas weight, were low at 29 d in the intestine and increased to 56 d. Pigs on diet B had the highest level of trypsin and chymotrypsin in the intestinal contents (P less than .05). Trypsin activity in the pancreas (units/kg body weight) was lowest (P less than .05) for pigs on diet B and highest (P less than .05) for those on diet C (units/g pancreas and units/kg body weight). Amylase activity (units/kg body weight) was lower (P less than .05) in the pancreas for pigs on diet B than for those on diets A and C. Pigs on diet A had lower (P less than .01) intestinal amylase activities than those on diets B and C. Enzyme activities in the intestinal contents and pancreas were low following weaning. In the pancreas, activities decreased at 31 d.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

16.
Twenty-one genetically lean, obese or contemporary barrows (6 mo old; seven of each genotype) were assigned to individual tether stalls and fed a control diet (low-fiber) or a diet containing 80% alfalfa meal (high-fiber) at 1.50% of initial body weight for 71 d (1.75% for d 1 to 4). Backfat thickness was recorded ultrasonically at 2-wk intervals, and body weight was recorded at the beginning and end of the 10-wk experiment. Pigs were slaughtered after a 24-h fast, and carcass weight, length and backfat thickness and cross-sectional area of the longissimus muscle were measured. Weights of cecum, heart, liver and kidney and of full and empty stomach and colon and empty small intestine were recorded. Volume and weight of colon and cecum contents were determined. Restriction of digestible energy reduced weight gain to zero or below in pigs fed alfalfa meal compared with 220 g daily in pigs fed the low-fiber diet. Restriction of energy reduced backfat in all three genotypes. Liver, kidney and empty segments of the gastrointestinal tract as a percentage of body weight were increased by high fiber. Obese pigs had smaller longissimus muscle area, more backfat and smaller liver, heart, empty stomach and colon than lean or contemporary pigs, but there were no diet X genotype interactions for any of these traits. Obese pigs consistently had smaller digesta volumes and dry matter weights than the other genotypes. The increased relative organ weights and the associated disproportionate contribution of these organs to body energy expenditure have important implications for effects on basal metabolic rate.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

17.
The fecal flora of 2 pigs given an optimal protein diet (digestive crude protein, 13.3%) with 2% urea, 2 pigs given a low protein diet (digestive crude protein, 5.7%) with 2% urea, and 2 pigs given a low protein diet only were bacteriologically investigated before feeding of each diet and on feeding days 21 and 38. The addition of urea to a low protein diet was significantly decreased Lactobacillus (P less than 0.001), Bacteroidaceae (P less than 0.01), Peptococcaceae (P less than 0.05), and Megasphaera (P less than 0.01) in the feces. In addition, there was a marked suppression of anaerobic curved rods (mainly Selenomonas) to undetectable amounts in the feces. A significant reduction (P less than 0.01) of Bifidobacterium and a marked suppression of Megasphaera to undetectable amounts were observed in the feces of pigs given low protein diets without urea. Microbial groups in the ileum and colon of pigs on feeding day 38 were also analyzed. Effects of dietary urea on the intestinal flora included: (i) anaerobic curved rods and spiral rods were restricted mainly to the colon, (ii) smaller numbers of yeasts were present in the intestine, and (iii) Bacteroidaceae, Peptococcaceae, and Eubacterium in the colon were not changed. Many anaerobic isolates, including curved rods and spiral rods, in the colon of pigs may have an important role in urea use.  相似文献   

18.
In a five-week feeding trial, 90 broiler chicks were used to study the response of serum and liver alanine aminotransferase (ALT) aspartate aminotransferase (AST), sorbitol dehydrogenase (SDH) and alkaline phosphatase following the replacement of varying levels (0, 20, 40, 60, 80 and 100 per cent) of fishmeal protein by soyabean meal protein. The results showed that both serum ALT and AST activities increased significantly (P less than 0.01) with the increasing levels of substitution of soyabean meal for fishmeal. Regression analysis showed a significant (P less than 0.01) positive correlation between ALT and AST activities and the level of soyabean meal substitution with correlation coefficient, r, of 0.93 and 0.98, respectively. The liver ALT and AST tended to increase with the increasing proportion of soyabean meal although such increases were not significant (P greater than 0.01). Serum and liver SDH and alkaline phosphatase activities were not significantly influenced by diet.  相似文献   

19.
The activities of eight enzymes (glutamate dehydrogenase, sorbital dehydrogenase, malate dehydrogenase, lactate dehydrogenase, alpha-hydroxy butyrate dehydrogenase, gamma-glutamyl transpeptidase, alkaline phosphatase and creatine kinase) were determined in tissue homogenates of liver, kidney, spleen, lung, small intestine, cardiac muscle and skeletal muscle, from 15 Large White pigs of three different ages (1.5 weeks, 18--22 weeks and 113 weeks). The results showed that variation in tissue enzyme concentration due to differences in sex is minimal. Variation due to differences in age, however, appears to be of greater importance, particularly when considering young animals. These age differences may affect the interpretation of plasma enzyme changes due to tissue damage, and the use of additional enzyme assays as an aid to interpretation in these cases is advisable.  相似文献   

20.
Porcine rotavirus was shown to infect gnotobiotic pigs and induce an acute enteric disease clinically characterized by diarrhea, anorexia, depression, and occasional vomition. Onset of clinical signs correlated closely with the appearance of lesions within the small intestinal mucosa, and recovery from infection was associated with the regeneration of normal, functional villous epithelium. Villous atrophy, especially in the caudal two-thirds of the small intestine, was the consistent lesion observed in pigs with clinical signs of rotaviral infection. Villi were often short, blunt, and covered with cuboidal epithelial cells. Immunofluorescent microscopy methods demonstrated that the principal site of rotaviral replication was the villous columnar epithelial cells in the small intestine.  相似文献   

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