植酸酶替代猪日粮中磷酸氢钙的饲喂效果

磷是动物机体必需的矿物元素。植物性饲料中的磷大部分以植酸或植酸盐的形式存在。而单胃动物肠道粘膜中的内源性植酸酶及肠道微生物产生的植酸酶活性很差(Ravindran V等，1995)，缺乏分解植酸的植酸酶，造成饲料中磷的利用率仅有1/3或更低。日粮中的磷只有很小部分沉积到体内和畜产品中，其余部分从粪便中排出。为了补充有效磷的不足，必须在饲料中添加无机磷酸盐。然而高密度畜禽养殖时，动物排泄物中的磷导致地下水、土壤污染以及水源富养化污染。     

猪日粮中同时添加甲酸和植酸酶

甲酸是非常有用的饲料防腐剂和酸化剂,但是甲酸对钢材和多种合金有腐蚀性,会在未安装液态有机酸处理设备的饲料厂中造成严重问题。然而,如今如果对设备进行升级换代以便能在饲料中添加甲酸,可能是很值得的,因为将甲酸和植酸酶同时应用,看来可大大改善猪的性能。遗憾...     

生长猪低磷日粮添加植酸酶和有机酸以及维生素D_3的研究

本试验通过添加植酸酶、有机酸(柠檬酸、抗坏血酸)和维生素D3、木聚糖酶来减少无机磷的添加量,提高饲料中植酸磷的利用率,降低磷的排泄量。选择30 kg左右的"斯格"纯种猪70头,随机分成7组:常磷组、低磷日粮组(NC)、NC+600 U/kg植酸酶组、NC+600 U/kg植酸酶+10 g/kg的柠檬酸、NC+600 U/kg植酸酶+10 g/kg的柠檬酸+200 mg/kg抗坏血酸、NC+600 U/kg植酸酶+10 g/kg的柠檬酸+200 mg/kg抗坏血酸+100μg/kg的维生素D3、不添加磷酸氢钙。所有日粮中都添加50 mg/kg木聚糖酶。结果表明:低磷日粮添加植酸酶、有机酸(柠檬酸、抗坏血酸)和维生素D3,平均日采食量无显著影响(P0.05),日增重显著提高(P0.05),料重比显著降低(P0.05);养分消化率均显著提高;血液指标着中,白蛋白显著降低(P0.05),碱性磷酸酶、总蛋白、谷草、谷丙转氨酶无影响(P0.05)。     

在猪日粮中添加植酸酶-木聚糖酶的作用

加拿大阿尔伯塔大学与Danisco公司合作研究了日粮中粗蛋白（CP）和在小麦基础日粮中添加植酸酶一木聚糖酶对生长肥育猪能量代谢和肠道甲烷产生的影响。试验将72头青年母猪单独饲养,自由采食6种以小麦为主的日粮：     

植酸酶在含有玉米副产品猪日粮中的效果

因为即使是不添加微生物型植酸酶,干酒糟副产品中的磷也可被猪充分地消化,所以添加植酸酶对提高这些成分中磷的消化率仅能产生极为有限的作用,因此并不经济。     

在双低菜籽粕和豆粕型日粮中添加植酸酶对生长猪磷真消化率的影响

用回归分析分别对生长猪双低菜籽粕（CM，试验1）和豆粕（SBM，实验2）型日粮中磷真消化率（TPD）进行估测，并量化了植酸酶对其的影响。试验分别用48头（实验1）或36头（实验2）均重为17kg的杂交仔猪以TPD为指标，随机分为6组，每2组1个处理，共3个处理；每个处理中每千克日粮含CM或SBM的量分别为：132g、264g及396g；每个处理2个重复，每个重复每千克日粮中植酸酶用量分别为0或1000IU。     

在双低菜籽粕和豆粕型日粮中添加植酸酶对生长猪磷真消化率的影响

用回归分析分别对生长猪双低菜籽粕（CM，试验1）和豆粕（SBM，实验2）型日粮中磷真消化率（TPD）进行估测，并量化了植酸酶对其的影响。试验分别用48头（实验1）或36头（实验2）均重为17kg的杂交仔猪以TPD为指标，随机分为6组，每2组1个处理，共3个处理；每个处理中每千克日粮含CM或SBM的量分别为：132g、264g及396g；每个处理2个重复，每个重复每千克日粮中植酸酶用量分别为0或1000IU。     

不同《饲养标准》下两种日粮对生长猪应用效果试验

猪的《饲养标准》是养猪生产的理论基础，也是进行实际饲养的指导依据。我国猪的两个饲养标准于20世纪80年代初制定，且自1985年修汀后多年未变，另一方面，到1998年为止，美国国家研究委员会(National Research Council，简称NRC)《猪的营养需要》已陆续发行十版，经过半个多世纪的发展，该标准已日益完善并逐渐成为目前世界范围内最具影响的猪的饲养     

Effect of Phytase Supplementation in Diets on Nutrient Digestibility and Performance in Broiler Chicks

A performance trial was conducted with broiler chicks to study the effect of phytase (PHY) supplementation in diets formulated with reduced AME, Ca, and P. The nutrient digestibility was determined during the 14- to 21-d and 28- to 35-d periods. The treatments consisted of 3 diets (NC1, NC2, NC3) differing in nutrient content and each diet with or without supplemental PHY (NC1, 0 or 500; NC2, 0 or 750; NC3, 0 or 1,000 U of PHY/kg feed) and 1 positive control diet (PC). Compared with the PC diet, negative control diets (NC) resulted in lower AME and apparent ileal amino acid digestibility for some amino acids. Phytase supplementation of the NC diets increased AME, apparent ileal amino acid digestibility, and apparent ileal crude protein digestibility. Phytase addition also increased mineral absorption in 21- and 35-d-old broilers fed NC diets. Reduced nutrient digestibility appears to be a factor in the weight gain and feed intake results. Reducing Ca and P content reduced feed intake in a stepwise fashion in the NC diets. Phytase increased feed intake and generally improved nutrient digestibility, which resulted in an increase in digestible nutrient intake. Averaged across NC diets, PHY improved body weight. Bone-breaking strength was the most consistent predictor of Ca and P reduction. All NC diets had significantly lower bone-breaking strength than the PC. Phytase supplementation of the NC diets gave bone-breaking strengths that were comparable to the PC. Diets with PHY had the highest bioeconomic index.     

Effects of Xylanase and Protease Supplementation on Nutrient Digestibility in Diets Based on Peas and Wheat Fed to Weaned Pigs

This experiment was conducted to determine the effects of a commercial enzyme mixture providing xylanase and protease activities on the di gesfibility of dietary nutrients when added to diets based on peas and wheat and fed to 9.5 to 15 kg pigs.Pigs were weaned at 18 to 21 days of age and fitted with a simple T-cannula at the distal ileum,6 to 7 days after weaning.After 5 to 7 days for adaptation to their diets,ileal digesta,and feces were collected.Enzyme supplementation had no effect on the apparent ileal or fecal digestibility of any dietary nutrient.There Was a numerical improvement(P＞0.05)in the ileal digestibility of fiber.In conclusion.xylanase and protease appeared to be ineffective in improving nutrient digestibility when supplemented in diets based on peas and wheat fed to weaned pigs.     

不同磷水平和钙磷比饲粮添加植酸酶对妊娠母猪养分表观消化率的影响

本试验旨在研究不同磷水平和钙磷比饲粮添加植酸酶对妊娠母猪养分消化率的影响。试验选择遗传背景一致、2~3胎次(预产期前28 d)、体重为(221.91±7.41)kg、预产期相近的健康"长×大"二元杂交母猪36头,按照胎次、预产期均衡原则随机分为9个组,每个组4个重复。对照组饲喂基础饲粮(钙、磷水平分别为7.26、5.81 g/kg);组2为基础饲粮添加植酸酶;组3~5保持钙水平(7.26 g/kg)不变添加植酸酶,减少无机磷添加至对照组的75%、50%、25%[钙磷比为(1.35~1.63)∶1.00];组6~9保持钙磷比不变(1.25∶1.00)添加植酸酶,减少无机磷添加至对照组的75%、50%、25%、0。结果表明:1)正常磷水平下,添加植酸酶显著提高了干物质、粗灰分、有机物和磷的表观消化率(P0.05),极显著降低了粪中磷的排泄量(P0.01),有降低铜、锌排泄量的趋势(P0.10)。与对照相比,低磷水平添加植酸酶极显著提高了干物质、粗灰分、有机物、磷、钙、铁、铜、锌的表观消化率(P0.01),显著降低了粪中磷、钙、铁、铜、锌的排泄量(P0.05)。2)饲粮在保持钙水平不变或钙磷比不变的条件下添加植酸酶,随磷添加量的降低,干物质、粗灰分、有机物、磷、铁、铜、锌的表观消化率均呈线性或二次升高(P0.05),粪中磷、铁、铜、锌的排泄量呈线性或二次降低(P0.01),保持钙磷比不变,钙、粗蛋白质的表观消化率显著提高(P0.05)。3)以表观可消化磷为标准,饲粮保持钙水平不变和钙磷比不变添加植酸酶可分别替代0.91、1.27 g/kg的无机磷,减少24.70%、34.48%的粪磷排泄量。4)钙磷比不变(1.25∶1.00)组饲粮的养分表观消化率极显著高于钙水平不变[高钙磷比(1.35~1.63)∶1.00]组饲粮(P0.01),且粪矿物质的排泄量极显著减少(P0.01)。综上所述:1)在本研究条件下,在低无机磷、低钙磷比(1.25∶1.00)饲粮中,添加植酸酶提高养分消化率的效果更显著。2)以表观可消化磷为标准,母猪饲粮的钙磷比为1.25∶1.00时,添加植酸酶可减少1.27 g/kg的磷添加。     

Effects of Source of Inorganic Phosphorus and Phytase Supplementation on Performance, Physiological Parameters and Bone Mineralization in Broilers

The objective of this study was to evaluate the effects of inorganic phosphorus source and phytase addition on performance, nutrient digestibility and bone mineralization in broiler chickens. In Exp. 1, 150 two-day old, male broiler chicks were fed a corn-soybean meal basal diet supplemented with phosphorus provided by dicalcium phosphate, tricalcium phosphate or defluorinated rock phosphate. Five cages containing 10 birds were allotted to each of the three treatments. In Exp. 2, 120 three-day old, male broiler chicks were fed the basal diet from Exp. 1 supplemented with 0, 250, 500, or 1,000 FTU phytase per kg of diet. Six cages containing five chicks were allotted to each of the four treatments. In Exp. 1, there was no difference in weight gain, feed intake or feed conversion as a result of feeding the different sources of inorganic phosphorus. The digestibility of phosphorus was significantly lower (P = 0.01) for chicks fed diets supplemented with tricalcium phosphate than for chicks fed the other two diets.  However, despite the lower digestibility, serum phosphorus levels did not differ among the three treatments. For Exp. 2, feed conversion showed a linear improvement (P = 0.03) with increasing levels of phytase inclusion (days 0 to 33).  Phytase supplementation resulted in linear increases in the digestibility of dry matter (P = 0.02), crude protein (P = 0.04) and energy (P < 0.01).  Chicks fed 1,000 FTU/kg phytase had significantly higher bone calcium (P = 0.05) and bone breaking strength (P = 0.04) than chicks fed the basal diet on day 33. In conclusion, the results of the current study indicated that the performance of birds fed diets supplemented with dicalcium phosphate, tricalcium phosphate or defluorinated phosphate was similar and therefore production costs could be lowered by choosing the cheapest inorganic phosphorus source when formulating diets for poultry. When diets were formulated to meet dietary phosphorus requirements, the growth of broilers was not enhanced with phytase supplementation.  However, increases in feed conversion and bone breaking strength and its potential to impact culling and mortality in broiler operations may be sufficient justification for the routine inclusion of phytase in diets fed to broilers.     

Effects of Source of Inorganic Phosphorus and Phytase Supplementation on Performance, Physiological Parameters and Bone Mineralization in Broilers

The objective of this study was to eval- uate the effects of inorganic phosphorus source and phytase addition on performance, nutrient digestibility and bone mineralization in broiler chickens. In Exp. 1,150 two-day old, male broiler chicks were fed a corn-soybean meal basal diet supplemented with phos- phorus provided by dicalcium phosphate, tricalcium phosphate or defluorinated rock phosphate. Five cages containing 10 birds were allotted to each of the three treatments. In Exp. 2,120 three-day old, male broiler chicks were fed the basal diet from Exp. 1 supplemen- ted with 0,250,500 ,or 1,000 P-＇rU phytase per kg of diet. Six cages containing five chicks were allotted to each of the four treatments. In Exp. 1, there was no difference in weight gain, feed intake or feed conver- sion as a result of feeding the different sources of in- organic phosphorus. The digestibility of phosphorus was significantly lower （P =0.01 ） for chicks fed di- ets supplemented with tricalcium phosphate than for chicks fed the other two diets. However, despite the lower digestibility, serum phosphorus levels did not differ among the three treatments. For Exp. 2, feedconversion showed a linear improvement （P = 0.03 ） with increasing levels of phytase inclusion （ days 0 to 33 ）. Phytase supplementation resulted in linear increa- ses in the digestibility of dry matter （P = 0.02 ）, crude protein （ P --- 0.04 ） and energy （ P 〈 0.01 ）. Chicks fed 1,000 FTU/kg phytase had significantly higher bone calcium （ P = 0.05 ） and bone breaking strength （P = 0.04 ） than chicks fed the basal diet on day 33. In conclusion, the results of the current study indicated that the performance of birds fed diets sup- plemented with dicalcium phosphate, tricalcium phos- phate or defluorinated phosphate was similar and therefore production costs could be lowered by choo- sing the cheapest inorganic phosphorus source when formulating diets for poultry. When diets were formu- lated to meet dietary phosphorus requirements, the growth of broilers was not enhanced with phytase sup- plementation. However, increases in feed conversion and bone breaking strength and its potential to impact culling and mortality in broiler operations may be suf- ficient justification for the routine inclusion of phytase in diets fed to broilers.     

Effect of Graded Levels of Wheat Distillers Grains with Solubles on Nutrient Digestibility, Performance and Carcass Traits of Growing-Finishing Pigs Fed Diets Based on Wheat and Field Peas

This trial was conducted to determine the effects of graded levels of wheat distillers dried grains with solubles (DDGS) on nutrient digestibility,performance and carcass characteristics of pigs (21.8 ...     

低蛋白日粮补充天冬氨酸对断奶至育肥阶段猪生长性能及肉品质性状的影响

旨在研究低蛋白日粮补充天冬氨酸对断奶至育肥阶段猪生长性能、血液生化指标和游离氨基酸、养分表观消化率以及肉品质性状的影响。选取20头45日龄,体重相近（（10.93±0.79） kg）的健康三元杂交（杜×长×大）断奶仔猪,随机分成两组,每组10个重复,每个重复1头猪,仔猪单栏饲养,试验期84 d。对照组饲喂玉米-豆粕型低蛋白基础日粮,试验组饲喂在基础日粮中添加0.5%天冬氨酸的试验饲粮。结果表明：1）添加天冬氨酸可显著提高猪断奶阶段平均日增重（P<0.05）并极显著降低料重比（P<0.01）,但在育肥和生长阶段对生长性能无显著影响（P>0.05）;2）添加天冬氨酸可显著提高断奶阶段血清白蛋白水平和碱性磷酸酶活性（P<0.05）,但对生长和育肥阶段血液生化指标均无显著影响（P>0.05）;3）添加天冬氨酸可显著降低断奶阶段血清中Pro、Met、Thr、Asp、His、Tyr含量（P<0.05）和提高Lys水平（P<0.01）,生长阶段血清中Asp、Lys含量和育肥阶段Asp、Thr含量显著降低（P<0.05）,对其他氨基酸含量无显著影响（P>0.05）;4）天冬氨酸处理可使育肥猪总能、粗蛋白、粗脂肪、粗灰分、粗纤维表观消化率极显著升高（P<0.01）;5）天冬氨酸处理可有效提高熟肉率（P<0.01）和背最长肌中MyHC1的mRNA表达水平（P<0.05）。综上可知,低蛋白日粮全程添加0.5%天冬氨酸可有效提高猪断奶阶段的生长性能,有利于促进其后期肌纤维的发育和改善其肉品质性状。     

低聚木糖对生长肥育猪生长性能、胴体性状和肉品质的影响

为了研究低聚木糖(XOS)对生长肥育猪生长性能、胴体性状和肉品质的影响,试验选取平均体重为30 kg左右的三元杂交猪80头,随机分为8组,每组10头,公、母各占1/2,单栏饲养。试验设对照组、抗生素组,3065 kg阶段100、250和500 g/t XOS组,以及30100 kg阶段100、250和500 g/t XOS组。分别于试验开始和结束时记录每头猪的空腹体重及采食量,计算平均日采食量(ADFI)、平均日增重(ADG)和料重比(F/G);于试猪平均体重达100 kg时屠宰采样,测定胴体性状、肉品质和肌肉化学成分。结果表明:与对照组或抗生素组相比,饲粮添加不同剂量的XOS对生长肥育猪的ADFI、ADG、F/G、胴体性状和肉品质均无显著影响(P0.05);3065 kg阶段添加250 g/t XOS可显著增加脾脏指数以及背最长肌粗蛋白质含量(P0.05);30100 kg阶段添加500 g/t XOS可显著增加脾脏指数及背最长肌粗蛋白质含量(P0.05)。综上所述,饲粮添加不同剂量的XOS虽对生长肥育猪的ADFI、ADG、F/G、胴体性状和肉品质等指标影响不显著,但可通过增加肌肉粗蛋白质含量而改善猪肉营养价值;以30100 kg阶段添加500 g/t XOS效果较佳。     

肌肽与维生素E对育肥猪肉品质和抗氧化性能的影响

本试验旨在研究肌肽与维生素E单独及联合使用对育肥猪肉品质和抗氧化性能的影响。试验采用2因素2×3析因设计,设3个肌肽水平(0、50、100 mg/kg),2个维生素E水平(0、200 mg/kg),选择90头体重约为70 kg的“杜×长×大”三元杂交育肥猪,按体重相近、性别比例相同原则,随机分为6组,每组3个重复,每个重复5头猪。预试期为7 d,试验期为42 d。结果表明:1)饲粮中添加肌肽能显著提高屠宰后45 min肌肉的p H和降低贮存48 h肌肉的滴水损失(P<0.05),极显著提高屠宰24 h后肌肉的p H和降低贮存24 h肌肉的滴水损失(P<0.01);维生素E能极显著降低贮存24和48 h肌肉的滴水损失(P<0.01),二者均能显著改善肉色(P<0.05)。肌肽与维生素E在改善肉色和降低贮存24 h肌肉的滴水损失上存在互作效应(P<0.05),且联合添加优于单独添加。2)饲粮中添加肌肽可显著提高育肥猪血清总抗氧化能力(T-AOC)及总超氧化物歧化酶(T-SOD)和过氧化氢酶(CAT)活性(P<0.05),极显著提高谷胱甘肽过氧化物酶(GSH-Px)活性(P<0.01),维生素E可极显著提高育肥猪血清T-AOC及T-SOD和GSH-Px活性(P<0.01)。在提高血清的T-AOC和GSH-Px活性上,二者存在显著互作效应(P<0.05),且联合添加优于单独添加。3)肌肽可显著降低贮存24 h背最长肌的丙二醛(MDA)含量(P<0.05),极显著降低贮存48、72和96 h背最长肌的MDA含量(P<0.01);维生素E可极显著降低贮存24、48、72和96 h背最长肌的MDA含量(P<0.01),且肌肽与维生素E对贮存48 h背最长肌的MDA含量存在显著互作效应(P<0.05)。综上,饲粮中添加100 mg/kg的肌肽、200 mg/kg的维生素E为最优组合。