益生菌制剂和植酸酶对育成期雉鸡生长、营养物质利用的影响

研究采用2×2因子试验设计,选择96只健康育成期环颈雉鸡,在基础日粮中添加益生菌EM(0.1%)、植酸酶(300U·kg-1)进行生长、代谢试验,研究EM、植酸酶对雉鸡育成期生长、营养物质利用的影响。结果表明:无论单一添加EM或植酸酶,还是同时添加EM和植酸酶,均能够显著提高促进育成期雉鸡的平均日增重,降低料重比,提高营养物质利用率。与对照组相比,EM、植酸酶处理组平均日增重分别提高8.95%(P<0.05)、5.34%(P<0.05),对采食量及平均体重无显著影响(P>0.05);同时添加EM、植酸酶处理组代谢能、粗蛋白及总磷表观消化率分别提高6.2%(P<0.05)、4.8%(P<0.05)、4.9%(P<0.05),而存留氮量提高6.45%(P<005),益生菌EM和植酸酶在雉鸡育成期生长性能和营养物质利用存在加性效应。     

钙和植酸酶对育成期蛋鸡生长和骨骼质量的影响

对日粮不同钙和植酸酶水平对育成期北京红鸡生长性能和骨骼质量的作用进行了研究。设计3×2因子试验,2个植酸酶水平为400U·kg~(-1),600U·kg~(-1),3个钙水平为0.60%,0.80%,1.0%。选用9周龄育成期北京红鸡384只,分成6组,每组4个重复,每重复16只鸡。饲喂玉米豆粕型基础日粮,含总磷0.40%,以石粉为主要钙源。试验期10周。结果表明:植酸酶水平的提高,采食量和胫骨灰分磷含量显著降低,铜、锰含量显著提高,增重、饲料转化率、胫骨灰分含量和锌含量有提高的趋势;胫骨折断力、灰分重和钙含量有降低的趋势。随日粮钙水平升高,采食量和胫骨灰分重提高了2%和10.75%,胫骨灰分中锰含量在0.80%钙组达到最高,而灰分中磷、铜含量达最低,增重、胫骨折断力、灰分含量和钙、锌含量有提高的趋势。钙和植酸酶在上述处理效应显著的指标上均存在互作。     

微生物植酸酶对生长肥育猪生产性能及钙、磷利用率的影响

本试验选用42头长杜大生长肥育猪研究微生杨植酸酶对生产性能及钙、磷利用率的影响。结果表明,饲粮中添加600FYT／kg和900FYT／kg微生物植酸酶均可达到添加磷酸氢钙（0．12％的磷）的生产性能．同时降低了钙、磷排泄量,改善了钙、磷的表观消化率和利用率。添加植酸酶600FYT／kg和900FYT／kg的效果差异不大。     

植酸酶对仔鸡生长和磷利用率的影响

选用180只1日龄AA肉鸡,随机分为对照组和试验组,研究在低有效磷日粮中添加AsN1980植酸酶干曲对肉仔鸡生长性能及磷利用的影响。研究结果表明:植酸酶对肉鸡生长和饲料中磷的利用率有明显促进作用,料肉比减少0 233～0 256,磷的利用率提高7 63%～8 27%,均优于对照组(P<0 05)。     

制粒温度对饲喂含植酸酶日粮肉仔鸡生长性能及钙磷利用的影响

选用160只1日龄肉仔鸡随机分为4组，每组设4个重复，以正常磷日粮为对照，研究在低磷日粮中添加植酸酶，分别于不同温度（75℃、80℃、85℃）制粒对肉仔鸡生长性能及钙、磷利用的影响。结果表明：①不同制粒温度条件下，低磷日粮添加植酸酶均可提高肉仔鸡的平均日增重和饲料利用率，75℃组好于其他温度组；②与对照组比较，2、3、4组肉仔鸡磷排出量（g／kg采食日粮）分别降低了33．45％、32．41％和29．66％（P〈O．05）；③除75℃组胫骨长度显著高于对照组外（P〈O．05），各试验组各项胫骨指标与对照组差异均不显著（P〉O．05）；④各组血清磷、血清钙、血清碱性磷酸酶差异不显著（P〉O．05）；⑤与对照组比较，各试验组的总磷、钙、粗蛋白、干物质表观消化率均提高（P〉O．05）。     

低磷日粮中添加包衣植酸酶对肉仔鸡生长性能和钙、磷利用率的影响

选用1日龄AA肉仔鸡360只进行为期6周的饲养试验。对照组饲喂有效磷含量为0.45%(0~3周)和0.40%(4~6周)的基础日粮,不添加包衣植酸酶;处理1、处理2饲喂有效磷含量为0.35%(0~3周)和0.30%(4~6周)的日粮,并分别在日粮中添加250、500 FTU/kg的包衣植酸酶;处理3、处理4饲喂有效磷含量为0.25%(0~3周)和0.20%(4~6周)的日粮,并分别在日粮中添加250、500 FTU/kg的包衣植酸酶。结果表明:与对照组相比,处理1、处理2的饲料利用率均得到显著提高(P<0.01),且日增重也有提高的趋势(P>0.05);处理3的日增重显著低于对照和其余各处理(P<0.05),其饲料利用率没有得到显著改善(P>0.05);处理4的日增重比对照有提高的趋势(P>0.05),且饲养后期的饲料利用率得到显著提高(P<0.01)。各处理的钙、磷消化率与对照差异不显著(P>0.05)。各处理的胫骨灰分和钙含量与对照差异不显著(P>0.05);处理4的胫骨磷含量显著高于对照(P<0.05),其余各处理与对照差异不显著(P>0.05)。     

植酸酶对仔猪生长性能及粪含磷量的影响

对１０９头断奶仔猪进行了饲料中添加植酸酶试验,观察其对仔猪生长性能的影响。试验分３批,设３个处理,每批各处理间的差异均不显著（ｐ＞０．０５）,表明仔猪饲料中添加植酸酶从而降低磷酸氢钙的用量,对仔猪生长无不良影响且明显降低粪磷的排出     

植酸酶对仔猪饲粮能量和蛋白质利用率影响的研究

选用48头长白×荣昌杂交仔猪进行2个2×2因子的代谢试验,每个试验均设2个有效磷水平(0 36%和0 26%)、2个植酸酶添加水平(0FTU/kg、750FTU/kg),共4个处理组,每个处理组设6个重复,每个重复1头仔猪。试验一为高能水平饲粮(DE:14 3MJ/kg),仔猪起始体重9 2kg;试验二为低能水平饲粮(DE:12 8MJ/kg),仔猪起始体重16 9kg,试验期二周。结果表明,在本试验条件下,饲粮中添加750FTU/kg植酸酶,改善蛋白质利用率,但对能量利用率没有明显影响。降低饲粮能量水平则降低能量和蛋白质利用率,降低饲粮有效磷水平则降低蛋白质利用率,低磷饲粮中添加750FTU/kg植酸酶时蛋白质利用率相似于或高于高磷饲粮。     

植酸酶对仔猪生产性能、养分表观消化率及粪、骨、血中钙、磷影响的研究

选用48头体重相近,体质健康的三元杂交(杜×长×大)仔猪为试验动物,随机分为2组,每组3个重复,每个重复8头,对照组为正常磷酸氢钙水平日粮,实验组日粮中添加5000 U/g植酸酶100 g/t替代50%磷酸氢钙。试验结果表明:在饲料中添加5000 U/g的植酸酶,能够使猪的日增重较对照组提高8．85%(P＜0．05),日采食量较对照组提高3．42%,饲料转化效率提高5．08%;钙、磷的表观消化率分别提高了14．29%(P＜0．05)、18．83%(P＜0．05),对粗蛋白质的表观消化率影响不大;添加植酸酶后粪中钙的排出减少21．05%(P＜0．01),粪中磷的排出减少17．91%(P＜0．01);骨中的钙、磷变化不大,全血中的钙提高了9．30%,磷提高了17．91%(P＜0．01);血清中钙提高12．62%,磷提高了7．08%。     

一组高效稳定纤维素分解菌复合系MC1的产酶条件

用CMC糖化力法和纤维素减重法探讨了对一组高效稳定的纤维素分解细菌复合系MC1的产酶条件。结果表明,在6种纤维素材料中,可直接利用的天然纤维素含量高的C源(如滤纸、棉花)存在下表现出高活性;利用蛋白胨和酵母粉作N源时的纤维素酶活性远高于硝酸铵、尿素等无机N源;以滤纸和酵母粉作为惟一C、N源时,最适发酵浓度分别为0.5%和0.125%,其产酶最高峰均出现在发酵第5d。MC1最适纤维素分解温度为55℃,但60℃以上的高温抑制MC1纤维素分解酶;MC1的最适氧气浓度为0.01～0.04mg·L-1,过高过低的氧气浓度均抑制纤维素分解。MC1的微好氧特点对堆肥工程降低生产成本具有重要意义。     

植酸酶对鲤钙磷等营养物质利用率的影响

从营养学角度出发，初步研究了添加植酸酶的饲料经不同温度（常温、６０℃，70℃、80℃、90℃；100℃）处理对鲤钙磷营养物质利用率的影响。通过10d的饲养，收集粪便分析发现：与对照组相比，添加植酸酶可以使钙的利用率提高132％以上，总磷利用率提高105－122％，74．86％－89．04％的植酸磷得以使用，蛋白质和脂肪的利用率约提高11％和12％。     

植酸酶对猪生产性能及养分利用率的影响

本试验研究了用植酸酶替代部分磷酸氢钙对猪生产性能、养分消化率、血液生化指标以及粪磷排泄量的影响.试验选取36头体质健康的三元杂(杜×长×大)生长猪,随机分成2个处理组,即对照组、试验组,每组3个重复,每个重复6头猪,公母各半.对照组饲喂高磷日粮,试验组饲喂低磷加酶日粮.试验结果表明,用植酸酶替代0.5%的磷酸氢钙不仅不影响生长猪的生长性能,且试验组与对照组相比日增重提高了16.69%(P<0.05),料肉比降低了12.84%(P<0.05).日粮中添加植酸酶后,干物质、蛋白质、钙、磷、能量的表观消化率分别提高了3.28%、5.17%、15.30%、15.58%、3.27%(P<0.05).添加植酸酶均对血液生化指标无显著影响(P>0.05),碱性磷酸酶活性以及血清钙浓度有下降的趋势,而血清磷浓度有上升的趋势.日粮中添加植酸酶粪磷排泄量下降28.01%(P<0.05),粪氮排泄量下降25.19%(P<0.05).     

肉牛饲喂不同处理玉米秸秆日粮营养物质消化和生产效益的差异比较

为了比较玉米秸秆不同处理方法对肉牛日粮营养物质表观消化和生产经济效益的影响,选用杂交肉牛16头,随机分为4个处理组(干玉米秸秆组、干秸秆青贮组、微生物处理组、氨化处理组)进行饲养试验和消化代谢试验.结果表明,肉牛饲喂不同处理秸秆日粮的营养物质表观消化率没有明显的差异(P<0.05),有机物表观消化率为53.3%～61.8%,秸秆处理可明显提高可消化有机物的进食量(DOM)和肉牛养殖经济效益,相对于其它处理组,秸秆氨化组的经济效益较高.     

环保型饲粮对生长猪生长性能和养分排泄量的影响

为研究低蛋白质饲粮添加植酸酶、非淀粉多糖酶(NSP)和氨基酸微量元素对生长猪生长性能、养分排泄量的影响,选用90头平均初始体重为(41.92±2.6)kg的杜长大三元杂交猪,分为5组,设置1组为对照组,试验组采用低蛋白饲粮,试验2组为添加植酸酶处理;试验3组为添加氨基酸微量元素+植酸酶处理,试验4组为添加植酸酶+NSP酶处理,试验5组为添加氨基酸微量元素+植酸酶+NSP酶,试验期38d。结果表明,试验2组平均日增重、料重比分别比1组提高7.64%和1.94%(P0.05),其余各组间差异不显著(P0.05);粪N浓度2、3、4、5组比1组分别降低18.58%、20.65%、23.01%和21.24%(P0.05);粪P浓度2、3、4、5组比1组分别降低40.23%、38.31%、39.08%和39.85%(P0.01);粪Cu、Fe浓度2、3、4、5组与1组相比极显著降低(P0.01);粪Zn浓度2、3、4、5组与1组相比显著降低(P0.05)。由此可见,低蛋白质饲粮添加植酸酶处理,能显著提高生长猪平均日增重,显著减少粪中氮、锌含量,极显著减少粪磷、铜、铁含量;在此基础上,继续应用氨基酸微量元素等量替代相应的无机硫酸盐及添加NSP酶均对生长猪生长性能和粪中养分含量的影响差异不显著。     

稻草和精料及非蛋白氮对水牛瘤胃纤维素酶活力的影响

试验用 3头安装永久性瘤胃瘘管的成年水牛。采用自身对照方式在不同日粮条件下分别测定了瘤胃液内纤维素酶 (CMCase和FPase)活力以及厌氧真菌孢子数量。试验分为 4期 :稻草期 (Ⅰ期 ) ,稻草 +精料期 (Ⅱ期 ) ,稻草、精料 +羟甲基尿素期 (Ⅲ期 )和稻草、精料、羟甲基尿素 +硫酸铵期 (Ⅳ期 ) ,每期 2 0d。Ⅱ期稻草添喂精料 (2kg/d)时CMCase和Fpase平均活力分别下降 39% (P <0 .0 1)和 11% (P <0 .0 5 ) ;Ⅲ期加入羟甲基尿素 (80 g/d)CM Case和Fpase平均活力比Ⅱ期上升 89% (P <0 .0 1)和 19(P <0 .0 5 ) ,且显著高于Ⅰ期 (P <0 .0 5 )。Ⅳ期饲喂稻草、精料、羟甲基尿素 +硫酸铵 ,FPase活力比Ⅲ期进一步提高 (9% ,P <0 .0 5 )。Ⅰ、Ⅱ、Ⅲ期之间真菌孢子数量没有显著差异 ,Ⅳ期显著低于其它 3期 (P <0 .0 5 )。结果表明稻草基础日粮添加淀粉等非结构多糖时加入羟甲基尿素和硫酸铵显著提高瘤胃微生物纤维素酶活性。     

The Effect of Dietary Supplementation with Phytase Transgenic Corn on Growth Performance,Phosphorus Utilization and Excretion in Growing Pigs （Sus scrofa）

Two experiments were conducted to investigate the effect of dietary supplementation with phytase transgenic corn (PTC)on growth performance, phosphorus (P) utilization and excretion in growing pigs. In Exp. 1, 180 pigs (Large White ×Landrace, BW=37.7 kg) were randomly allotted to 4 treatments with 5 replicates of 9 pigs each in order to evaluate the effect of PTC supplementation in low-P diets on growth performance. Four corn soybean meal-based diets consisted of a positive control (PC) diet, a diet containing 500 units (U) of exogenous phytase kg-1 (EP) on the basis of low-P (inorganic P reduced by 0.05% from PC diet) and the low-P+500 (PTC1) or 750 (PTC2) phytase U ofPTC kg-1. In Exp. 2, 20 barrows (Large White×Landrace, BW=31 kg, 4 treatments with 5 replicates of 1 pig each) were randomly selected to evaluate the effect of PTC in low-P diets on serum parameters and nutrient utilization. Diets in Exp. 2 were similar to those in Exp. 1except that the EP group was replaced by a low-P diet without exogenous phytase supplementation as a negative control (NC) group. The results from Exp. 1 showed that the average daily gain (ADG) in the PTC2 group was significantly higher (P＜0.05) than that in the EP group over all periods. On the other hand, the feed:gain (F:G) ratio of the EP group was significantly higher (P＜0.05) than that of the PTC2 group during 1-21 and 1-42 d, respectively. There were no differences in average daily feed intake (ADFI) among all treatments (P＞0.05). The results from Exp. 2 showed that the concentration of serum Ca in the NC group was the highest (P＜0.05), while the concentration of serum P in the PTC2 group was the highest (P＜0.05) among all treatments. There was a significant decrease (P＜0.05) in the P apparent digestibility of the NC group compared with the other groups, and that of PTC2 group was the best. Furthermore, fecal P excretion was reduced (P＜0.05) from 1.80 g d-1 in the PC group to 1.28 g d-1 in the PTC2 group. In conclusion, dietary supplementation with PTC could reduce the application of inorganic P, decrease fecal P excretion, and improve the growth performance of growing pigs.     

Effects of Fermentation Product Containing Phytase on Productive Performance,Egg Quality,and Phosphorous Apparent Metabolism of Laying Hens Fed Different Levels of Phosphorus

This study investigated the effects of fermentation product containing phytase （FPP） that was fermented using waste vinegar residue （WVR） as substrate from Aspergillusficuum NTG-23 on productive performance, egg quality, and phosphorus apparent metabolism of laying hens. First, 375 22-wk-old Jinghong hens were allocated into 5 treatments （5 replicates of 15 hens each） in an 8-wk experiment for evaluating the parameters of productive performance, egg quality, serum, and tibia. Experimental diets contained 4% FPP and 96% corn-soybean diet. The levels of dicalciurn phosphate （DCP） were 1.34, 1.01, 0.67, 0.34 and 0%. Next, thirty 31-wk-old Jinghong hens were fed 5 types of diets for evaluating phosphorous apparent metabolism rate. Egg productive rate, egg weight, feed conversion ratio, Haugh unit, egg albumen height, serum calcium, tibia ash, tibia ash calcium and tibia breaking strength were not different significantly among 5 treatments. The significant difference of average daily feed intake was not appeared when the DCP content of corn-soybean-FPP diet was reduced to 0.67%; the eggshell hardness, eggshell thickness and serum phosphorus were not reduced significantly until the DCP content of corn-soybean-FPP diet was reduced to 0.34%. The yolk color was improved when the laying hens fed deficient DCP corn-soybean-FPP diet. A 22.14% reduction in excreta phosphorus was observed when the laying hens fed low phosphorus （0.67% DCP） corn-soybean-FPP diet. A 30% elevation of phosphorus apparent metabolism rate was obtained when the DCP content of corn-soybean-FPP diet was decreased from 1.34 to 1.01%. The reducing cost of layer diet was totalized about 120 CNY 1000 kg1 diet when the content of DCP was 0.67% in corn-soybean-FPP diet. These results indicated that FPP could be applied in laying hen as a potential, cost-effective and rational application of WVR.     

Effect of Wheat Middlings, Microbial Phytase, and Citric Acid on Phytate- Phosphorus, Calcium, and Protein Utilization of Broilers

A corn-soybean meal diet （CSB） （or Diet 1） containing 23% crude protein （CP） was used as the positive control, and another corn-soybean meal diet containing 21% CP and 15% wheat middlings （WM） （or Diet 2） was used as the basal diet, which was treated with four different treatments. Digestibility experiment was employed to discuss the collective effect of citric acid, and intrinsic and microbial phytase. By comparing and analyzing effects of them in the low-nutrient broiler diets, the results showed five treatments had similar effects on Tibia ash （%） （mg） （P〉0.05）. Under the supplementation of bacterial phytase or citric acid, the daily body weight gain （ADG）, gain：feed （G：F） ratio, and calcium （Ca） utilization were similar to that of standard-nutrient CSB diet （Diet 1） （P 〉 0.05）. And, fecal phosphorus （P） and CP utilization were lower than （P〈0.05） that of Diet 1. But P utilization was significantly higher than （P〈0.01） that of Diet 1. However, the ADG, G：F, and CP utilization produced by supplementation of intrinsic phytase were lower than those of Diet 1, but other aspects were similar to those produced by Diet 1 （P〉0.05）. In Diet 5, citric acid, intrinsic and bacterial phytase were added to the diet, which produced a 1.4% decrease on fecal P, a 7.2% increase on Ca utilization, which was significantly higher than （P〈0.01） those of the other four Diets, a 3.9% increase on G：F, which was similar to that of Diet 1, and a 2.3% increase on CP utilization, which was higher than （P〈0.05） that of the other three diets. In summary, the results of this study indicated that citric acid, intrinsic and bacterial phytase might have some additive or synergistic effects, and low-nutrient CSB diets with 15% wheat middlings, 750 U kg^-1 phytase, and 3% citric acid might substitute completely for standard CSB in broilers.     

纤维素酶及相关基因克隆的研究进展

纤维素酶能有效地将纤维素物质水解成单糖进而发酵生产乙醇、氢气以及微生物油脂等,因此纤维素酶日益受到人们的关注.但纤维素酶的大规模工业化应用在很大程度上却受纤维索酶活较低以及成本较高的限制.纤维素酶基因克隆为研究纤维素酶的生物合成和作用机制以及了解纤维素酶遗传特性进而构建高效纤维素分解菌开辟了新的途径.     

植酸酶对肉鸡生长及磷利用率的影响

在饲料中降低无机磷用量,添加不同的比例黑曲霉植酸酶,以确定其对鸡的作用效果。结果表明,在０￣３周龄肉鸡饲料中添加质量分数为０．０５％和０．１０％的植酸酶后,无机磷的添加量从对照组的１．３８％降到处理组的１．０６％;添加同样比例的植酸酶,４￣７周龄肉鸡饲料中的无机磷添加量从对照组的１．１４％降到处理组的０．８３％和０．５２％。添加植酸酶,降低无机磷用量后对肉鸡的增重无显著影响。肉鸡血清中无机磷的含量