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1.
The efficacy of Aspergillus niger (APhy) phytase, Trichoderma reesei (TPhy) phytase and acid phosphatase (TAcPh) preparations in improving the utilization of phytin-phosphorus in the maize-soybean meal (SBM) or barley-SBM (800:200 g kg-1) diets was studied in two separate digestibility and balance trials with ten growing pigs using 5 x 5 Latin square designs. The positive control diet contained a total phosphorus (P) of 6.5 g kg-1, while the negative control as well as the APhy, TPhy and TAcPh supplemented diets which did not contain additional inorganic-P, had a total P of 4.1 g kg-1. The APhy and TPhy supplements provided phytase activity of 1000 PU g-1 together with AcPh of 8000 HFU g-1. TAcPh at a level of 8000 HFU g-1 was the only addition to one diet. The intrinsic phytase activity of barley was 355 PU g-1 while maize and soybean meal showed no phytase activity. Phytase supplements of the APhy and TPhy sources increased ash digestibility in both diets but had only a minor effect on nitrogen utilization. The addition of phytase improved absorption of P by 21%-units in barley-SBM diet and 29%-units in maize-SBM diet, without any difference between the two phytase sources. The retained P in diets with phytase was higher than in diets without phytase, 4.4 (APhy), 4.5 (TPhy) vs. 2.9 g d-1 in barley-SBM-diets and 3.7 (APhy), 4.0 (TPhy) vs. 1.8 g d-1 in maize-SBM-diets. No difference was found between the two sources of phytase. TAcPh without additional phytase did not show any effect on P absorption or retention. Ca absorption and retention were improved due to the phytase treatments. Supplementing pig diets with either APhy or TPhy sources seems to be equally effective in enhancing the availability of phytate-P. Consequently, these supplements can reduce the P-excretion of pigs by 32-40% as compared with the diet supplemented with inorganic-P.  相似文献   

2.
3.
通过模拟生长猪消化道环境,以玉米、豆粕和菜粕为植酸磷的载体,考察了不同酸源对微生物植酸酶体外释放植酸磷的影响。结果显示,在体外近似体内条件下(37℃、2.5h、pH值3~6),酸梅粉和植酸酶(500U/kg)联用释放不同饲料中的植酸磷比例最大,其次是柠檬酸,盐酸最低。  相似文献   

4.
麦类籽实中植酸酶的活性及体外降解植酸盐效果的研究   总被引:1,自引:0,他引:1  
为评价不同麦类籽实中内源植酸酶的活性及其对外源植酸盐的降解能力,以植酸钠为底物,测定5种10个不同品种麦类籽实中植酸酶的活性;在37℃、pH 5.50的条件下,以300 U/kg的浓度加入从麦类籽实中提取的植酸酶,检测了对玉米、豆粕中植酸磷的释放效果。结果表明,燕麦、大麦(垦啤2号)、小麦(东农123)、小麦(东农973821)、小黑麦(5305)、小黑麦(92021)、小黑麦(96026)、小黑麦(8809)、胜利黑麦和黑麦(2号)籽实中植酸酶的活性分别为57.50、143.25、1048.06、725.22、1978.67、2201.65、1713.46、1406.49、5310.89 U/kg和3446.53 U/kg(风干基础);在上述条件下,反应8h,玉米、豆粕中的植酸磷分别释放71.92%和38.94%。  相似文献   

5.
We have recently expressed a new phytase enzyme in a yeast system. Three experiments with a total of 140 weanling crossbred pigs were conducted to examine the efficacy of this enzyme in improving the bioavailability of phytate-P in corn-soybean meal diets to young pigs. Experiment 1 compared the efficacy of this new phytase with a commercially available phytase (Natuphos, BASF) for 4 wk at an inclusion level of 1,200 U/kg of diet. Experiment 2 compared the responses of pigs to four doses of the new phytase supplementation (300, 600, 900, and 1,200 U/kg of diet) for 4 wk. Experiment 3 compared the efficacy of this new phytase and Natuphos at a marginally optimal dose (700 U/kg of diet) for 5 wk. A group of pigs were fed the P-deficient basal diet as a negative control in Exp. 1, and a group of pigs were fed the basal diet plus .17 or .22% inorganic P as a positive control in all experiments. In Exp. 1, pigs fed the two sources of phytase had similar ADG (564 vs 567 g), gain/feed (.597 vs .589), plasma inorganic P concentrations (8.9 vs 8.4 mg/dL), and mobility scores (4.25 vs 4.46) that were higher (P < .05) than those of the negative control. In Exp. 2, plasma inorganic P concentration was a fairly linear response to the phytase dose (r > .83) at wk 1 and 2. Overall ADG of pigs also tended to increase with the phytase dose (P = .15). In Exp. 3, pigs fed the two sources of phytase had ADG (483 vs 506 g) similar to that of the positive control (508 g). These two groups also had similar plasma inorganic P concentrations (7.7 vs 7.4 mg/dL) that were lower (P < .05) than those of the positive control group (9.7 mg/dL). There was no significant effect of dietary treatments on ADFI in all three experiments. In conclusion, our new phytase was as effective as Natuphos, at the inclusion level of 700 or 1,200 U/kg of a P-deficient, corn-soybean meal diet, in improving phytate-P utilization by young pigs.  相似文献   

6.
Availability of phytate-bound P as influenced by supplemental phytase was studied in eight horses consuming four diets in a 4 x 4 Latin square design experiment. The treatments were a control (containing a low P level, 18.4 g/d) and three high-P diets. These diets contained P as monocalcium phosphate (MCP; 43.7 g/d), myoinositol hexakisphosphate in the form of wheat and rice bran (MIHP; 41.8 g/d), or MIHP with microbial phytase (MIHPP; 42.5 g/d). The proportions of phytate-bound P were 3, 1, 55, and 56% for the control, MCP, MIHP, and MIHPP, respectively. The MIHPP diet was supplemented with 300 phytase units (FTU)/kg (as-fed basis). Feces and urine were collected quantitatively and analyzed for P, Ca, and Mg. Urinary P excretion was lower (P < 0.05) with the control diet (0 g of P/d) than with the MCP diet (1.0 g of P/d). The low urinary P excretion (0.3 g of P/d) for the MIHP diet suggested low P availability compared with the MCP diet, but apparent digestibility of P expressed as a percentage of intake did not differ (P = 0.065) between these diets. Apparent Ca digestibility was lower (P < 0.05) for the MIHP diet than for the MCP diet (26.4 vs. 42.4%). This difference may have been caused by the origin of the Ca in these diets. Phytase supplementation increased apparent Ca digestibility from 26.4 to 31.5% (P < 0.05). Magnesium was not influenced by the level of phytate in the diet. Our data indicate that phytase supplementation had more influence on Ca digestibility than on P digestibility and suggest that phytase supplementation may be beneficial for improving Ca digestibility for horses receiving a phytate-rich diet.  相似文献   

7.
The objective of this study was to investigate the effect of dietary phytate and phytase on the metabolic parameters of lipid, protein, enzyme, electrolyte in the blood or intestinal mucosa of broiler chickens. Diets containing phytate phosphorus (0.22% or 0.44%) with phytase supplementation (0, 500 or 1000 U/kg) were administrated to 504 Cobb chicks for 4 weeks. Results showed that the serum concentrations of total cholesterol (T‐CHO), albumin, albumin/globulin, total superoxide dismutase (T‐SOD), total antioxidant capacity (T‐AOC) and glutamic pyruvic transaminase (GPT) were decreased by 9–41% in high phytate diets (p < 0.05) and the concentrations of blood P, K, Fe, Cu, Zn and Mg were decreased by 4–14% for birds fed high phytate diets (p < 0.05), whereas inclusion of phytase compensated these adverse influences. In the duodenum, phytate decreased the level of T‐AOC by 13% (p < 0.05), whereas phytase increased the levels of T‐SOD, T‐AOC and alkaline phosphatase (ALP) by 9–16% (p < 0.05). Also, in the jejunum, diets with high phytate showed lower activity of T‐SOD, T‐AOC and glutamic oxaloacetic transaminase (GOT) (p < 0.05), and phytase increased T‐SOD, T‐AOC and ALP (p < 0.05). However, phytase decreased transaminase activity in the low phytate basal diets (p < 0.05). This study suggests that dietary phytate can adversely interfere with the metabolisms of lipid and protein, as well as the antioxidation of blood and intestinal cells, while phytase supplementation may compensate these effects for broiler chickens.  相似文献   

8.
Previous studies have suggested that organic acids may improve P utilization in animals. To evaluate the ability of ethylenediaminetetraacetic acid (EDTA) to improve phytate P utilization and the possible synergistic effect between EDTA and microbial phytase (MP) an experiment was conducted using 360 Ross 308 broiler chicks. The experiment was carried out using a completely randomized design with a 3*2 factorial arrangement (0, 0.1 and 0.2% EDTA and 0 and 500 IU MP). Four replicate of 15 chicks per each were fed dietary treatments including (i) P-deficient basal diet [0.2% available phosphorus (aP)] (NC); (ii) NC + 500 IU MP per kilogram of diet; (iii) NC + 0.1% EDTA per kilogram of diet; (iv) NC + 0.1% EDTA and 500 IU MP per kilogram of diet; (v) NC + 0.2% EDTA per kilogram; and (vi) NC + 0.2% EDTA + 500 IU MP per kilogram of diet. Weight gain (WG), feed efficiency and serum Ca, P and alkaline phosphatase (ALP) were assessed. Addition of 0.2% EDTA to low aP diets resulted in significantly lower feed consumption (FC) and WG, but 0.1% EDTA did not depress WG compared to NC. Phytase supplementation of P-deficient diets significantly improved WG and feed efficiency, but it had no effect on FC. Microbial phytase supplementation significantly decreased ALP concentration. Results obtained in our study suggest no synergistic effect between phytase and EDTA in broiler chicks.  相似文献   

9.
10.
Yersinia ruckeri is the aetiological agent of enteric redmouth disease (ERM), an acute to chronic bacteraemic infection of salmonid fish. The O-serotypes of 127 isolates of Y. ruckeri obtained from Europe (96 isolates), North America (23 isolates), Australia (six isolates) and South Africa (two isolates), as well as four reference strains, were determined by slide agglutination test and microplate agglutination assay. A serotyping scheme is proposed based on heat-stable O-antigens; the serotypes were designated O1, O2, O5, O6 and O7. The proposed scheme is compared to serotyping schemes described by other authors. All five O-serotypes were present in both Europe and North America, whereas only serotype O1 isolates were identified in Australia and South Africa. These findings suggest that European and North American populations of Y. ruckeri are interrelated, thus supporting previous evidence which suggests that the organism was introduced into Europe from North America by the importation of asymptomatic infected carrier fish. Conversely, the results suggest that Australia and South Africa are more isolated from the dissemination of Y. ruckeri. Serotypes O5, O6 and O7 have not previously been recognized in Europe and these findings will have important implications on the diagnosis of ERM and on the vaccination of fish against this disease. It is suggested that the Australian isolate previously described as serotype III is a rough-type mutant and that other isolates described in the literature as serotype III have been incorrectly serotyped and are, in fact, serotype O1. To avoid further confusion it is suggested that the scheme described here be adopted for serological studies of Y. ruckeri.  相似文献   

11.
在大口黑鲈饲料中添加不同水平植酸酶(500、1000、1500U/kg),研究在不同反应时间、温度和pH值条件下饲料中植酸磷的降解率的变化。结果显示,植酸磷的降解率与植酸酶添加量的关系为1500U/kg>1000U/kg>500U/kg。饲料中添加500U/kg植酸酶可分解70%左右的植酸磷,添加1000U/kg植酸酶可分解85%左右的植酸磷,添加1500U/kg植酸酶可分解93%左右的植酸磷。1500和1000U/kg组植酸磷的降解率在催化3h后基本趋于平缓,500U/kg组植酸磷降解率在催化4h后趋于平缓。在20~40℃范围内,植酸磷的降解率随催化温度的升高而增加。在pH值1.5~6.5范围内,植酸磷降解率有两个高峰点,分别出现在pH值为2.5与5.5,在pH值为6.5时,各组饲料中植酸磷的降解率最低。在大口黑鲈饲料中添加植酸酶是可行的。  相似文献   

12.
1. Five hundred and seventy six-d old Ross 308 broiler chicks (6 cages per diet, 8 birds per cage in 3 × 2 × 2 factorial arrangement) were fed on maize–soybean meal-based diets containing three concentrations of Ca (6, 8 or 10 g/kg), two concentrations of non-phytate phosphorus (NPP) (3 or 4 g/kg) and two levels of exogenous microbial phytase (0 or 500 FTU/kg) from d 0 to 35.

2. Body weight (BW), feed intake (FI) and mortality records were collected. Two birds per replicate were killed at 24 d of age to obtain tibia samples.

3. Increasing Ca level significantly reduced the FI and body weight gain (BWG) between hatch and 10 and 24 d, especially with the phytase-supplemented diets. However, phytase supplementation of the diet containing 4 g NPP/kg improved the FI and BWG at d 10 and 24. At d 24, phytase supplementation improved feed conversion ratio (FCR) of birds that consumed diets containing high NPP. The overall FCR was better in birds offered the phytase-supplemented, medium-Ca diet.

4. There was a significant reduction in length, width and breaking strength of the tibia bone in birds fed on a diet with high Ca and low NPP. Phytase supplementation improved the tibia ash content and bone breaking strength of chicks fed on the diet containing 8 and 4 g/kg Ca and NPP, respectively. The Ca content of the tibia bone was low in birds fed on diets with 6 and 4 g/kg Ca and NPP, respectively, but this was counteracted by phytase supplementation.

5. Birds fed on diets with 4 g/kg NPP had the best carcass percentage and parts yield. Phytase supplementation to high-Ca diets significantly reduced the carcass yield of birds.

6. These results confirmed the detrimental effect of high dietary Ca on phytase activity and subsequent growth and bone development of birds, especially when NPP is in short supply.  相似文献   


13.
Bluetongue virus (BTV) is an arthropod-borne virus infecting domestic and wild ruminants. Infection in cattle is commonly asymptomatic and characterised by a long viraemia. Associated with the emergence and the recrudescence of BTV serotype 8 (BTV-8) in Northern and Central Europe, remarkable differences have been noticed in the transmission and in the clinical expression of the disease, with cattle showing clinical illness and reproductive disorders such as abortion, stillbirth and fetal abnormalities. Several investigations have already indicated the putative ability of the European BTV-8 strain to cross the bovine placenta and to cause congenital infections. The current epidemiological and pathological findings present an unusual picture of the disease in affected bovines.  相似文献   

14.
The effect of dietary phytate and phytase on carbohydrase activity and hexose transport was investigated in broiler chickens. Diets containing phytate P (2.2 or 4.4 g/kg) with different phytase dose rates (0, 500, or 1,000 phytase units/kg) were fed to 504 female Cobb chicks for 3 wk. Diets containing high phytate concentrations depressed (P < 0.05) BW and G:F, whereas phytase supplementation improved (P < 0.05) the performance of birds. In the duodenum, phytate decreased (P < 0.05) the activities of disaccharidases, Na(+)K(+)-ATPase, and glucose concentrations by 5 to 11%, but phytase enhanced (P < 0.05) the concentrations of amylase, sucrase, maltase, Na(+)K(+)-ATPase, and glucose by 5 to 30%. In the jejunum, phytate decreased (P < 0.05) the concentrations of amylase, sucrase, Na(+)K(+)-ATPase, and glucose by 10 to 22%, and phytase alleviated the negative effect of phytate on the above variables. Ingestion of diets containing phytate also decreased (P < 0.05) serum amylase activity and glucose concentration, and phytase enhanced (P < 0.05) serum concentrations of amylase, sucrase, maltase, Na(+)K(+)-ATPase, and glucose. There were also interactions (P < 0.05) between phytate and phytase on the concentrations of serum amylase, duodenal amylase, sucrase, and jejunal glucose. Enzymatic analysis at a molecular level showed that neither phytate nor phytase influenced the mRNA expression of sucrase-isomaltase in the small intestine. Also, the investigation into the sodium glucose cotransporter gene may challenge the mechanism by which phytate interferes with glucose utilization, as partly indicated by bird performance, and transmembrane transport because diets containing increased phytate upregulated (P < 0.05) the mRNA expression of the sodium glucose cotransporter gene in duodenum and did not influence it in the jejunum. These results indicate that phytate can impair endogenous carbohydrase activity and digestive competence, and phytase can ameliorate these effects for chickens.  相似文献   

15.
1. Two trials were carried out to investigate the impact of intermittent feeding and oat hulls as methods to stimulate the anterior digestive tract in broiler chickens.

2. In Trial 1, 7-d-old broilers were placed 4 per cage in 48 cages and fed either ad libitum or intermittently on a diet with 50 g/kg of either oat hulls or cellulose, with or without 1000 FTU phytase, in a 2 × 2 × 2 factorial arrangement. Ad libitum fed birds had two 4-h dark periods with 1-h light in between, while intermittently fed birds in addition had restricted access to feed through four 1 h feeding bouts.

3. In Trial 2, 144 broiler chickens were divided amongst 12 pens which were intermittently fed on the same diets as in Trial 1 in a 2 × 2 factorial arrangement. At 34 d of age, after 16 h feed withdrawal, birds were fed for 1 h, followed by dissection of 4 birds per treatment every hour for 9 h. Contents from different segments of the digestive tract were collected quantitatively to assess dry matter (DM) and starch flow.

4. In Trial 1, phytase improved performance and nutrient availability, while oat hulls and intermittent feeding improved some measures of nutrient availability. Intermittent feeding augmented the effect of phytase on myo-inositol hexakisphosphate (IP6) degradation in the anterior digestive tract.

5. In Trial 2, birds filled up their crop and slowly passed these contents on to lower segments of the digestive tract. Already 1 h after commencement of feeding, the entire length of the small intestine was filled with DM, and no significant changes in DM content were observed before 4–5 h later, when the small intestine gradually became emptied. The tendency for a higher initial load of DM and starch in birds without oat hulls seems to support the hypothesis that one important function of the gizzard is feed-flow regulation.

6. In conclusion, the anterior digestive tract seems to have an important regulative function in broiler chickens when stimulated by intermittent feeding or structural components. More research is needed in order to elucidate the role of the crop and gizzard for phytase function.  相似文献   


16.
The use of dry feeds for dogs is increasing for different reasons: in comparison to wet canned feed it is easier to handle, the amount to be given is smaller and the daily cost is less. In producing a dry pellet more vegetable ingredients are used that can contain several antinutritional factors. Some of them can be eliminated by heating. Others like galactosides and phytates are heat-resistant but can be broken down by adding the appropriate enzymes. The specific enzymes are indeed not secreted by the animal itself. In farm animals, e.g. pigs, alpha-galactosidase has been introduced in order to enhance the energetic value of these alphagalactosides (Veldman et al. 1993). In companion animals this enzyme is more often indicated as an antiflatulence agent, because the main alpha-galactosides present in legume seeds (stachyose, raffinose) are known as flatulence components (Fleming 1981). These oligosaccharides do not necessarily imply an overall lower nutrient digestibility. Zuo et al. (1996) did not prove a significant difference in digestibility between conventional and low oligosaccharide soybean meal in dog rations. Others however, (Wiernusz et al. 1995) reported the highest digestibilities and the best stool quality of those rations that contained the least amount of soybean oligosaccharides. On the other hand, phytates (phospho-inositols) are known as complexing agents of several divalent cations (Fe, Mg, Zn, Ca) and are themselves considered as a phosphorus source, unavailable to monogastric animals. Phytase is the appropriate enzyme, which is not secreted by the animal itself, but, when added to the diet, can enhance the bio-availability of several minerals and trace elements (Rimbach et al. 1994) by hydrolysing the phospho-inositol molecule. The aim of the experiment, reported here, is to investigate the influence of the addition of alpha-galactosidase, phytase, or both to a nearly complete vegetable ration, consisting of a relatively high content of galactosides and phytates. The combination of both enzymes was carried out because Wenk et al. (1993) reported a possible interaction between a carbohydrase and a phytase enzyme in pigs.  相似文献   

17.
<正>1植酸酶活性与磷当量之间的关系酶活指酶催化其底物能力的大小,通常用活力单位来表示。目前国际上通用的植酸酶酶活定义为37℃及pH值5.5的条件下,1min内从5.1mmol/l的植酸钠溶液中水解1μmol无机磷所需要的酶量为一个酶活单位。所谓当量关系就是不同物质之间针对某一共  相似文献   

18.
1. Three experiments were conducted to evaluate the effects of the dietary addition of fungal phytase (derived from Aspergillus niger) on the performance and phosphorus utilisation in broiler chickens receiving low phosphorus diets without additional inorganic phosphates.

2. Graded amounts of supplemental phytase (125, 250, or 500 PU/kg diet) resulted in significant increases in both growth rate and food intake. However, only moderate improvements in food conversion were noted.

3. The enhancement of chick performance was related to an improved utilisation of dietary phosphorus, as confirmed by significantly elevated plasma concentrations of inorganic phosphorus and increased tibia ash percentages in birds receiving phytase‐treated diets. The apparent availability of phosphorus was markedly improved and its concentration in excreta was reduced (experiment 1, P<0.05).

4. It was concluded that an inclusion of phytase into practical broiler diet will allow the reduction or omission of additional dietary inorganic phosphorus.  相似文献   


19.
Scrapie is a fatal, neurodegenerative disease of sheep and goats. It is also the earliest known member in the family of diseases classified as transmissible spongiform encephalopathies (TSE) or prion diseases, which includes Creutzfeldt-Jakob disease in humans, bovine spongiform encephalopathy (BSE), and chronic wasting disease in cervids. The recent revelation of naturally occurring BSE in a goat has brought the issue of TSE in goats to the attention of the public. In contrast to scrapie, BSE presents a proven risk to humans. The risk of goat BSE, however, is difficult to evaluate, as our knowledge of TSE in goats is limited. Natural caprine scrapie has been discovered throughout Europe, with reported cases generally being greatest in countries with the highest goat populations. As with sheep scrapie, susceptibility and incubation period duration of goat scrapie are most likely controlled by the prion protein (PrP) gene (PRNP). Like the PRNP of sheep, the caprine PRNP shows significantly greater variability than that of cattle and humans. Although PRNP variability in goats differs from that observed in sheep, the two species share several identical alleles. Moreover, while the ARR allele associated with enhancing resistance in sheep is not present in the goat PRNP, there is evidence for the existence of other PrP variants related to resistance. This review presents the current knowledge of the epidemiology of caprine scrapie within the major European goat populations, and compiles the current data on genetic variability of PRNP.  相似文献   

20.
The trial was performed to investigate the effects of different concentrations of non‐phytate phosphorus (nPP) in the starter and grower (with phytase inclusion) periods on carcass characteristics, organ weight and weekly variations of growth performance in the grower period. Seven hundred and twenty‐day‐old male broiler chickens were randomly assigned to 12 treatments in a completely randomized design. Chickens received two dietary treatments (4.5 g/kg and 6 g/kg nPP) in the starter (0–21 days) and six experimental diets (4 g/kg, 3.1 g/kg, 2.3 g/kg and 2.3 g/kg + 1000 FTU/Kg of feed phytase, 1.5 g/kg, 1.5 g/kg nPP + 1000 FTU/Kg of feed phytase) in the grower period (22–42 days). Results showed that phytase inclusion in the second and third weeks of grower period could increase feed intake significantly. Also, decrease in the concentrations of nPP to 1.5 g/kg caused to decline body weight gain markedly. Moreover, there is a significant difference between 4.5 g/kg and 6 + 4 g/kg nPP (starter+grower) and 1.5 g/kg nPP. Phytase inclusion increased carcass yield and declined liver weight significantly. Dietary treatment of 4.5 + 1.5 g/kg nPP enhanced heart and liver weight markedly. It is concluded that starter diets with increased concentration of nPP (6 g/kg nPP) had no beneficial effects on growth performance in the starter and grower period in the total (0–42 days). Also, it is possible to decrease nPP concentration of grower diets to 1.5 and 2.3 g/kg with and without phytase inclusion respectively.  相似文献   

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