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1.
The exogenous enzymes are less consistent in their effects as their beneficial effects depend upon the types and level non-starch polysaccharides (NSP) present in the diets. Therefore, exogenous enzymes should be selected on the basis of types and amount of the NSP in the pig diets. The objectives of the present experiments were to investigate the effects of dietary level of mannan and β-mannanase supplementation on growth performance, apparent total tract digestibility (ATTD) of energy and nutrients, and blood metabolites of growing pigs. In Exp. 1, 96 barrows were randomly allotted to four treatments on the basis of BW. There were four replicates in each treatment with six pigs per replicate. The dietary treatments were a corn–soybean meal (SBM)-based control diet and three other diets consisted of the control diet supplemented with 400, 800 or 1600 U of β-mannanase/kg diet. The final BW, average daily gain (ADG) and blood glucose increased (linear, P<0.05) with increasing concentrations of dietary β-mannanase. The ATTD of dry matter (DM), gross energy (GE) and β-mannan was higher (linear, P<0.05) with increase in dietary β-mannanase concentrations. In Exp. 2, 288 barrows were allotted to six treatments in a 2×3 factorial arrangement of mannan level (high v. low) and addition of β-mannanase (0, 400 or 800 U/kg diet). There were four replicates in each treatment with 12 pigs/replicate. Pigs were fed corn–SBM-based low-mannan diet (6.1 g/kg) or high-mannan (25.2 g/kg) diet in which corn and SBM were partially replaced with 50 g/kg diet palm kernel meal. All diets were fed in meal form for 42 days. Pigs fed diets supplemented with β-mannanase had greater (P<0.05) final BW, ADG, feed to gain (F : G), the ATTD of DM, GE, and β-mannan and blood glucose concentration compared with pigs fed diets without β-mannanase. In addition, the final BW, ADG, F : G and the ATTD of GE and β-mannan were reduced (P<0.05) in low mannan level. The dietary level of mannan and the β-mannanase supplementation had no effects (P>0.05) on the concentrations of blood total cholesterol, triacylglycerides and blood urea nitrogen. These results indicate that supplementation of β-mannanase to low- or high-mannan diets have potential to improve the performance of growing pigs. In addition, palm kernel meal may partially replace corn and SBM without reducing pig performance if β-mannanase is added to diet.  相似文献   

2.
A study was conducted to determine the efficacy of β-mannanase supplementation to a diet based on corn and soya bean meal (SBM) on growth performance, nutrient digestibility, blood urea nitrogen (BUN), faecal coliforms and lactic acid bacteria, and noxious gas emission in growing pigs. A total of 140 pigs [(Landrace × Yorkshire) × Duroc; average body weight 25 ± 3 kg] were randomly allotted to a 2 × 2 factorial arrangement with dietary treatments consisting of hulled or dehulled SBM without or with supplementation of 400 U β-mannanase/kg. During the 6 weeks of experimental feeding, β-mannanase supplementation had no effect on body weight gain, feed intake and gain:feed (G:F) ratio. Compared with dehulled SBM, feeding hulled SBM caused an increased feed intake of pigs in the entire trial (p = 0.05). The G:F ratio was improved in pigs receiving dehulled SBM (p < 0.05). Dietary treatments did not influence the total tract digestibility of dry matter, nitrogen and gross energy. Enzyme supplementation reduced (p < 0.05) the population of faecal coliforms and tended to reduce the NH3 concentration after 24 h of fermentation in a closed box containing faecal slurry. Feeding hulled SBM tended to reduce NH3 emission on days 3 and 5 of fermentation. In conclusion, mannanase supplementation had no influence on growth performance and nutrient digestibility but showed a positive effect on reducing coliform population and tended to reduce NH3 emission. Dehulled SBM increased G:F ratio and hulled SBM tended to reduce NH3 emission.  相似文献   

3.
The study was focused on assessment of the effect of an extract of long-chain inulin (LCI) and dried tubers of Jerusalem artichoke (JA) and a multispecies probiotic preparation as well as a combination thereof on growth performance and blood parameters of fattening pigs. In total, 144 pigs (initial body weight 30.0 ± 0.5 kg) were used in a 98-d experiment. The six dietary treatments consisted of the control diet (Con), diet Con supplemented with probiotics (ConP) and four diets supplemented with LCI or JA alone or with probiotics (diets LCIP and JAP). Throughout the fattening period, there was a beneficial effect of the probiotic supplementation to the inulin-containing diets and the average daily gain (ADG) was increased by supplementation of probiotics in combination with inulin sources (p < 0.05). At the end of the fattening period, ADG and feed conversion ratio (FCR) were higher after supplementation of LCI only (p < 0.05). Compared with group ConP, in groups LCI and JA, the ADG and FCR were improved (p < 0.05). Only in the first fattening stage, the addition of the prebiotics and/or probiotics had an impact on the level of white blood cells and some biochemical indices in pigs. In younger animals, probiotic or LCI supplementation increased the IgG level (p < 0.05). There was also an interaction between the probiotics and JA resulting in increased IgG and IgA concentrations (p < 0.05). In the finishing period, LCI addition increased the IgM level (p < 0.05), whereas JA addition increased IgG and IgM levels as well (p < 0.05). In conclusion, both dietary sources of inulin and probiotic supplementation can improve the fattening performance and health status of growing pigs.  相似文献   

4.
This study was conducted to investigate the effects of rumen-protected γ-aminobutyric acid (GABA) on feed intake, growth performance and expression of related genes in growing lambs. A total of 24 lambs weaned at age of 50 days were divided into four block of six based on their BW, six lambs within a block were allocated to three pairs, which were then assigned randomly to three treatments with addition of rumen-protected GABA at levels of 0, 70 or 140 mg/day for 6 weeks. Dry matter intake was recorded weekly in three consecutive days, and BW was recorded every two weeks. At the end of the trial, four lambs from each group were slaughtered, and duodenum and ileum mucosa were obtained for measurement of mRNA abundance of GABA receptor and cholecystokinin receptor. Dry matter intake was higher (P<0.01) in the lambs fed 140 mg/day GABA than that in the control or 70 mg GABA-fed lambs. Average daily gain and nutrients digestibility were not different (P>0.05) among treatments. Lambs fed 140 mg/day GABA had higher mRNA abundance of GABA-B receptor (P<0.01) and lower mRNA abundance of cholecystokinin-2 receptor (P<0.01) in duodenum mucosa. Serum CCK content was lower (P<0.01) in lambs fed 140 mg/day GABA than that in control. It is indicated that GABA may enhance feed intake by regulating GABA- and cholecystokinin-related genes.  相似文献   

5.
The mechanism of diabetic embryopathy is not known. Excessive reactive oxygen species (ROS) produced in diabetes may be causally related to foetal anomalies. The objective of this study was to determine whether supplementation with the antioxidant lipoic acid (LA) could prevent maternal diabetes-related foetal malformations and intrauterine growth retardation (IUGR) in rats. Pregnant rats were non-treated (Group I) or made diabetic on gestation day (GD) 2 by injecting streptozotocin (Group II). Group III was injected with 20 mg kg–1 of LA daily starting on GD 6 and continued through GD 19. Group IV was administered only Tris buffer on the corresponding days. Group V was a set of STZ-treated animals, which were supplemented with a daily dose of 20 mg kg–1 of LA from GD 6 through GD 19. All fetuses were collected on GD 20. Lipoic acid did not affect the blood sugar levels of diabetic animals significantly but improved their body weight gain and reduced food and water consumption. Diabetic group had a high incidence of embryonic resorption, IUGR, craniofacial malformations, supernumerary ribs and skeletal hypoplasia. Lipoic acid significantly reduced these abnormalities. These data support the hypothesis that ROS are causally related to fetal maldevelopment and IUGR associated with maternal diabetes in the rat. They also highlight the possible role of antioxidants in the normal processes of embryo survival, growth and development. (Mol Cell Biochem 261: 123–135, 2004)  相似文献   

6.
Summary Effects of -galactosidase (from green coffee beans) digestion on lectin staining were examined in formalin-fixed, paraffin-embedded human pancreatic tissues from individuals of blood-group B and AB. Digestion with the enzyme resulted in almost complete loss of Griffonia simplicifolia agglutinin I-B4(GSAI-B4) staining in the acinar cells with concomitant appearance of Ulex europaeus agglutinin-I(UEA-I) staining in the corresponding cells. In addition, reactivity with soybean agglutinin(SBA) was also imparted by the enzyme digestion in GSAI-B4 positive acinar cells. -Galactosidase digestion following -galactosidase digestion neither reduced the reactivity with SBA nor induced the reactivity with Griffonia simplicifolia agglutinin-II(GSA-II) in GSAI-B4 positive cells, while in UEA-I positive cells, both reduction of SBA reactivity and appearance of GSA-II reactivity occurred after simple -galactosidase digestion as well as sequential digestion with - and -galactosidase. However, when -l-fucosidase digestion procedure was inserted between - and -galactosidase digestion, UEA-I staining imparted by -galactosidase digestion was markedly decreased in intensity and GSA-II reactivity was appeared in GSAI-B4 positive acinar cells. Furthermore, after sequential digestion with -galactosidase and fucosidase, reactivity with peanut agglutinin(PNA) was revealed in GSAI-B4 positive acinar cells as well as UEA-I positive cells in secretors. In non-secretors, strong PNA staining was usually observed in the acinar cells throughout the glands without enzyme digestion. These results confirmed that the -galactosidase induced GSA-II reactivity and the fucosidase induced PNA reactivity are due to precursors of different kinds of blood-group determinants and suggest that at least two kinds of B antigen determinants, i.e. Gal(1-3)[Fuc(1-2)]Gal(1-3,4)GlcNac and Gal(1-3)-[Fuc(1-2)]Gal(1-3)GalNAc are produced in GSAI-B4 positive acinar cells. The synthesis of the latter type of B antigen is assumed to be controlled under the secretory gene in human pancreas.Abbreviation GalNAc N-acetyl-d-galactosamine - Gal d-galactose - GlcNAc N-acetyl-d-glucosamine - Fuc l-fucose - NeuNAc N-acetylneuraminic acid (sialic acid)  相似文献   

7.
8.
The purpose of this study was to examine the effectiveness of β-alanine as an ergogenic aid in tests of anaerobic power output after 8 weeks of high-intensity interval, repeated sprint, and resistance training in previously trained collegiate wrestlers (WR) and football (FB) players. Twenty-two college WRs (19.9 ± 1.9 years, age ± SD) and 15 college FB players (18.6 ± 1.5 years) participated in this double-blind, placebo-controlled study. Each subject ingested either 4 g·d β-alanine or placebo in powdered capsule form. Subjects were tested pre and posttreatment in timed 300-yd shuttle, 90° flexed-arm hang (FAH), body composition, and blood lactate after 300-yd shuttle. Although not statistically significant (p > 0.05) subjects taking β-alanine achieved more desirable results on all tests compared to those on placebo. Performance improvements were greatest in the FB supplement group, decreasing 300 shuttle time by 1.1 seconds (vs. 0.4-second placebo) and increasing FAH (3.0 vs. 0.39 seconds). The wrestlers, both placebo and supplement, lost weight (as was the goal, i.e., weight bracket allowance); however, the supplement group increased lean mass by 1.1 lb, whereas the placebo group lost lean mass (-0.98 lb). Both FB groups gained weight; however, the supplement group gained an average 2.1-lb lean mass compared to 1.1 lb for placebo. β-Alanine appears to have the ability to augment performance and stimulate lean mass accrual in a short amount of time (8 weeks) in previously trained athletes. Training regimen may have an effect on the degree of benefit from β-alanine supplementation.  相似文献   

9.
When Cellulomonas flavigena CDBB-531 was grown on glucose, xylose, glycerol, solka floc, sugarcane bagasse or xylan, xylanase activity was found only in the fermentation broth, while -xylosidase activity was always associated with the cells. Both enzymes were inducible, sugar-cane bagasse was the best inducer, solka floc and avicel were moderately good, while xylan was poor. A synergistic effect on xylanase and -xylosidase synthesis was observed when cellulose and hemicellulose were used together as carbon sources. When this strain was grown on glucose, cellobiose, arabinose or xylose, only low levels of both enzymes were detected. These results indicate that xylanase and -xylosidase were carbon-source-repressed by readily metabolizable substrates. The effect of glycerol on enzymes that were already induced was studied. The addition of glycerol caused a significant decrease in the levels of xylanases, while -xylosidase activity remained unchanged.  相似文献   

10.
Silber  A.  Ganmore-Neumann  R.  Ben-Jaacov  J. 《Plant and Soil》1998,199(2):205-211
A greenhouse experiment was conducted to establish the optimal fertilization management for Leucadendron Safari Sunset (Leucadendron salignum × L. laureolum). Addition of NPK and micronutrient fertilizer or raising phosphorus concentration by itself increased total fresh weight and improved plant growth. Elevating the total nutrients or P concentration increased N and P concentrations. Clusters of proteoid roots were present along the root system of plants irrigated with tap-water, whereas few proteoid roots developed on plants irrigated with complete nutrient solution when only P was omitted, and none developed in any of the other treatments with P present.The pH in leachate of plants irrigated with tap water or with high nutrient levels (100, 20 and 100 mg L-1 of N, P and K, respectively) was consistently lower compared with leachate without plants. Increasing concentration resulted in a significant change in the pH values (pH in leachate with plant – pH in leachate without plant) from negative to positive. This phenomenon is probably related to rhizosphere effects due to plant and microbial activity.  相似文献   

11.
ABSTRACT

Five ruminally and duodenally cannulated Kazakh male lambs (30 ± 2.75 kg) maintained singly in a metabolic cage were used in a 5 × 5 Latin square experiment to investigate the effect of supplementing a ration with five different levels of distillers’ grape residue (DGR) on ruminal degradability, whole tract digestibility and nitrogen (N) metabolism of growing lambs. The rations were isoenergetic and isonitrogenous and contained 0, 3.85, 7.70, 11.55 and 15.41% DGR (DM basis). Each experimental period lasted for 18 d: 10 d for adaptation to the dietary treatment and 8 d for faecal, urinary, ruminal and duodenal digesta sample collections. The outflow rate of ruminal digesta increased (p = 0.032) linearly with the increased level of dietary neutral detergent fibre content, caused by the supplementation of DGR. As a result, the effective degradability of dry matter and crude protein decreased significantly with the treatments. Although the dietary intake of N, duodenal flow of total N, and the endogenous N at the duodenum were not affected by experimental treatments, N fractions in the digesta were altered. Ruminal microbial N decreased (p < 0.01) linearly; in contrast, ruminal un-degradable protein increased linearly (p < 0.01) in response to the increased addition of DGR. Although there was no significant difference in faecal N among treatments, N retention was increased linearly (p = 0.014), owing to the remarkable reduction (p = 0.016) of urinary N excretion with an increasing level of DGR. The results indicate that the DGR has some potential benefits of increasing the supply of bypass protein and of improving the utilisation efficiency of N for sheep. Therefore, the supplementation of DGR in ruminant feeding is recommended at levels not exceeding 10% of the diet.  相似文献   

12.
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14.
The effect of intramuscular injections of vitamin E on growth, carcass traits, intramuscular collagen (IMC) characteristics and decorin of growing lambs was studied. A total of 24 15-day-old Ile de France suckling male lambs were divided into two groups and weekly intramuscular injections of DL-α-tocopheryl acetate (control group, 0 IU; Vitamin E treatment, 150 IU) were given until the lambs were 64 days old. Lambs were individually weighted at 15, 29, 43, 57 days of age and at slaughter (71 days old). Dry matter intake and average daily weight gain were recorded. Hot and cold carcass weights were recorded and dressing percentages were calculated after dressing and chilling (2°C to 4°C for 24 h). Carcass shrink losses were calculated as well. Longissimus muscle (LM) pH and area were measured. The pelvic limb was removed and its percentage was calculated based on cold carcass weight. IMC and decorin analyses were assessed on LM and semimembranosus muscle (SM). DL-α-tocopheryl acetate treatment reduced (P<0.05) collagen maturity and increased (P<0.05) decorin in both LM and SM muscles of growing lambs, while it did not affect IMC content. In addition, vitamin E did not influence growth, carcass weight, dressing percentage, carcass shrink losses and area of LM but decreased (P<0.05) the pelvic limb percentage. The LM pH values were higher (P<0.05) in vitamin group than in control group. Furthermore, different IMC characteristics between the muscles (P<0.01) were apparent. Multiple intramuscular injections of DL-α-tocopheryl acetate influence extracellular matrix in lambs, which could affect meat tenderness.  相似文献   

15.
Insect α-amylase inhibiting and/or growth inhibiting activities of proteinaceous inhibitors from red kidney bean (Phaseolus vulgaris) and hard red winter wheat (Triticum aestivum) were examined. The bean inhibitor was most effectivein vitro against α-amylases from the red flour beetle (Tribolium castaneum) and the confused flour beetle (T. confusum), followed by those from the rice weevil (Sitophilus oryzae) and yellow mealworm (Tenebrio molitor). The insect enzymes were from two- to 50-fold more susceptible than human salivary α-amylase. When the inhibitors were added at a 1% level to a wheat flour plus germ diet, the growth of red flour beetle larvae was slowed relative to that of the control group of larvae, with the bean inhibitor being more effective than the wheat inhibitor. Development of both the red flour beetle and flat grain beetle (Cryptolestes pusillus) was delayed by 1% bean inhibitor, but development of the sawtoothed grain beetle (Oryzaephilus surinamensis) and lesser grain borer (Rhyzopertha dominica) was not affected by either the bean or wheat inhibitor at the 1% level. Rice weevil adults fed a diet containing 1% bean or wheat inhibitor exhibited more mortality than weevils fed the control diet. When the wheat amylase inhibitor was combined with a cysteine protease inhibitor, E-64, and fed to red flour beetle larvae, a reduction in the growth rate and an increase in the time required for adult eclosion occurred relative to larvae fed either of the inhibitors separately. The bean inhibitor was just as effective alone as when it was combined with the protease inhibitor. These results demonstrate that plant inhibitors of insect digestive enzymes act as growth inhibitors of insects and possibly as plant defense proteins, and open the way to the use of the genes of these inhibitors for genetically improving the resistance of cereals to storage pests. Cooperative investigation between the Agricultural Research Service, the University of California, San Diego, and the Kansas Agricultural Experiment Station (Contribution no. 94-416-J). Supported in part by a grant from the Ministry of Education and Science, Spain-Fulbright Program to J.J.P. Mention of a proprietary product does not constitute a recommendation or endorsement by the USDA. The USDA is an equal opportunity/affirmative action employer and all agency services are available without discrimination.  相似文献   

16.
The role of ornithine decarboxylase and of polyamines was investigated on caerulein-induced pancreatic growth by the use of α-difluoromethylornithine (DFMO), an enzyme-activated irreversible inhibitor of ornithine decarboxylase. By itself, DFMO did not affect the pancreatic gland at all but when combined with caerulein, it reduced the increases in DNA synthesis and DNA content initiated by the cholecystokinin analog. The general hypertrophic action of caerulein was not affected by DFMO but specific increases in amylase and chymotrypsin concentrations were observed after 2 days of caerulein. The effect on amylase concentration was further increased after 4 days but that on chymotrypsin was reversed, showing a significant decrease. These data suggest that the polyamines might be involved in pancreatic growth that is stimulated by caerulein and that their action could be mainly oriented towards cellularity. The specific decreases obtained in DNA synthesis and content brought about by DFMO support this observation.  相似文献   

17.
Apparent ileal digestibility (AID) of energy, dry matter (DM), nitrogen (N) and amino acids and standardized ileal digestibility (SID) of amino acids in low quality soybean meals with different CP concentration (SBM 44% CP and SBM 48% CP) with or without 400 U β-mannanase/kg supplementation were evaluated in 20 cannulated barrows ((Landrace×Yorkshire)×Duroc) with an average BW of 25.08±3.42 kg. A N-free diet was used to determine basal endogenous losses of amino acids. The supplementation of β-mannanase improved (P<0.05) AID of DM compared with non-supplemented diet. However, enzyme supplementation did not improve (P>0.05) AID of N and energy. The type of SBM (SBM 44% CP v. SBM 48% CP) had no effect on AID of DM, N and energy. β-mannanase improved (P<0.05) AID of sum of essential amino acids, arginine, histidine, lysine, valine and glycine. The SID of lysine was higher (P<0.05) in enzyme supplemented than in non-supplemented diets. Larger AID and SID of threonine and proline (P<0.05) were observed in SBM 48% CP than in SBM 44% CP. In conclusion, the supplementation of enzyme improved AID of arginine, histidine, lysine, valine and glycine, but it did not cause marked difference in SID of these amino acids except for lysine. The low nutrient digestibility of the SBM sources used in the present experiment might have favoured the positive effect of β-mannanase supplementation.  相似文献   

18.
α-Galactosidase from tomato has been immobilized on Sepabead EC-EA and Sepabead EC-HA, which were activated with ethylendiamino and hexamethylenediamino groups, respectively. Two strategy was used for the covalent immobilization of α-galactosidase on the aminated Sepabeads: covalent immobilization of enzyme on glutaraldehyde activated support and cross-linking of the adsorbed enzymes on to the support with glutaraldehyde. By using these two methods, all the immobilized enzymes retained very high activity and the stability of the enzyme was also improved. The obtained results showed that, the most stable immobilized α-galactosidase was obtained with the second strategy. The immobilized enzymes were characterized with respect to free counterpart. Some parameters effecting to the enzyme activity and stability were also analyzed. The optimum temperature and pH were found as 60 °C and pH 5.5 for all immobilized enzymes, respectively. All the immobilized α-galactosidases were more thermostable than the free enzyme at 50 °C. The stabilities of the Sepabead EC-EA and EC-HA adsorbed enzymes treated with glutaraldehyde compared to the stability of the free enzyme were a factor of 6 for Sepabead EC-EA and 5.3 for Sepabead EC-HA. Both the free and immobilized enzymes were very stable between pH 3.0 and 6.0 and more than 85% of the initial activities were recovered. Under the identical storage conditions the free enzyme lost its initial activity more quickly than the immobilized enzymes at the same period of time. The immobilized α-galactosidase seems to fulfill the requirements for different industrial applications.  相似文献   

19.
Behavior and average daily gain were evaluated after mixing pigs amongst litters or maintaining them as littermate groups, after weaning and initially limit or full fed. Limit fed mixed groups fought most and gained least of the treatment groups. Limit fed littermate groups fought least of the groups. Limit feeding after moving and mixing pigs amongst litters may reduce pathological conditions but was not demonstrated to reduce behavioral stress, as indicated by the expression of agonistic behavior.  相似文献   

20.
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