电针复合静松灵麻醉对山羊痛阈及生理生化的影响

 【目的】了解电针复合静松灵麻醉对山羊麻醉痛阈值及生理生化指标的影响。【方法】30只成年杂交山羊,体重22—27 kg,随机分为0.5 mg•kg-1静松灵组、2 mg•kg-1静松灵组、电针复合0.5 mg•kg-1静松灵组、电针组和空白对照组,每组6只,公母各半。分别在给药后0、5、25、45、65和85 min（单纯药物组）,或电针后0、25、45、65、85、105 min（电针组或电针复合药物组）采用钾离子透入法测定痛阈值,并测定呼吸频率、心率、平均股动脉压、体温等生理指标,于试验前及试验后1.5、24、48、96和168 h,采集山羊血液分别测定丙氨酸氨基转移酶活性、天门冬氨酸氨基转移酶活性、血清尿素含量、血糖含量、皮质醇含量等指标。【结果】电针复合0.5 mg•kg-1静松灵组山羊的痛阈在给药后显著高于单纯电针组和0.5 mg•kg-1静松灵组（P＜0.05）,而与2 mg•kg-1静松灵组无显著性差异（P＞0.05）;电针复合0.5 mg•kg-1静松灵组山羊的呼吸频率、平均股动脉压、天门冬氨酸氨基转移酶活性以及血清葡萄糖、尿素和皮质醇含量与对照组无显著差异（P＞0.05）,而0.5 mg•kg-1静松灵组与2 mg•kg-1静松灵组山羊天门冬氨酸氨基转移酶活性及血清葡萄糖、尿素或皮质醇含量与对照组差异显著（P＜0.05）;电针复合0.5 mg•kg-1静松灵对山羊的心率、体温和丙氨酸氨基转移酶活性的影响显著低于0.5 mg•kg-1或2 mg•kg-1静松灵（P＜0.05）。【结论】山羊电针复合静松灵麻醉痛阈值高,麻醉效果较好,生理生化指标干扰小。     

低浓度恩诺沙星对离体恒化器模型中人体肠道菌群的影响

 【目的】应用离体恒化器模型评价低浓度恩诺沙星对人体肠道菌群的影响,为制定微生物学日允许摄入量（ADI）提供依据。【方法】四套接种人体肠道菌群的离体恒化器模型中连续添加0、0.2、2及20 mg•L-1恩诺沙星8 d,采用细菌培养计数和PCR-DGGE方法研究细菌数量、耐药性、菌群结构和定植抗力的变化。【结果】2及20 mg•L-1恩诺沙星可抑制肠道总厌氧菌、总需氧菌和兼性厌氧菌、大肠杆菌、肠球菌的生长（P＜0.05或P＜0.01）;0.2、2及20 mg•L-1恩诺沙星均使总需氧和兼性厌氧菌、大肠杆菌耐药百分率增加（P＜0.05或P＜0.01）, 停药7 d后,总需氧和兼性厌氧菌、大肠杆菌耐药百分率呈下降趋势,但与对照组相比仍处于较高水平（P＜0.01）。20 mg•L-1恩诺沙星对肠道菌群结构的影响较大,使PCR-DGGE图谱发生明显变化,条带数、菌群多态性和相似性参数降低（P＜0.05或P＜0.01）;2和20 mg•L-1恩诺沙星可使肠道菌群对外源沙门氏菌的定植抗力明显下降。【结论】0.2 mg•L-1恩诺沙星（相当于3.67μg•kg-1体重）可对离体恒化器模型中的人体肠道菌群耐药性产生显著影响,说明中国现行规定的恩诺沙星和环丙沙星的ADI（6.2μg•kg-1体重）可能会对人体肠道菌群产生影响,主要为选择出耐药需氧和兼性厌氧菌。     

日粮中添加无机磷和植酸酶对肉鸡骨骼及生长性能的影响

【目的】研究不同无机磷水平日粮中添加植酸酶对肉鸡生长性能及骨骼的影响,以确定适宜的无机磷和植酸酶用量。【方法】选取1日龄肉鸡1 500只,随机分为5个处理,对照组日粮中添加16.3 g/kg磷酸氢钙,其余4组分别添加12.3,8.2,4.1和0 g/kg磷酸氢钙后再添加500 FTU/kg植酸酶,各组钙磷比为1.2~1.4,测定各组鸡的生长性能、胫骨鲜重、胫骨脱脂重、胫骨灰分和矿物质元素含量以及胫骨折断强度。【结果】未添加磷酸氢钙组肉鸡的日平均采食量、日增重均显著低于对照组(P<0.05);添加8.2 g/kg磷酸氢钙组肉鸡日增重最高,料重比最低;肉鸡胫骨鲜重、脱脂率在各处理间差异不显著(P>0.05),脱脂率随日粮中添加无机磷水平的降低而升高;胫骨脱脂重随日粮中无机磷水平下降而降低,28日龄未添加磷酸氢钙组肉鸡的胫骨脱脂重显著低于其他组(P<0.05)。28日龄肉鸡胫骨灰分含量以未添加磷酸氢钙组显著低于其他各组(P<0.05);胫骨钙、磷含量以未添加磷酸氢钙组低于其他各组,但各组差异不显著(P>0.05);28日龄肉鸡胫骨镁、锰、铜、铁、锌含量随日粮中无机磷添加水平的降低而逐渐升高,42日龄肉鸡胫骨镁、锰、铁含量在添加植酸酶组也有同样变化。肉鸡胫骨折断强度以未添加磷酸氢钙组低于其他各组,其中28日龄肉鸡该组胫骨折断强度显著低于其他组(P<0.05)。【结论】日粮中添加植酸酶能提高肉鸡生长性能及矿物质元素的利用率,但不能完全替代磷酸氢钙,以添加8.2 g/kg磷酸氢钙组(0~4周龄:Ca 7.6 g/kg,总磷(TP)5.4 g/kg;5~7周龄:Ca 7.0 g/kg,TP 5.3 g/kg)后再添加植酸酶对肉鸡的饲养效果较好,鉴于植酸酶对矿物元素的释放作用,有必要重新评定日粮配方中矿物元素的需要量。     

植酸酶和非淀粉多糖酶对肉鸡氮磷利用率的影响

选用1日龄健康黄羽肉鸡600羽随机分成4组，每组3个重复，每重复50羽，饲喂玉米－豆粕型日粮，研究日粮添加植酸酶和（或）非淀粉多糖酶对机体N和P的利用率、骨骼和血清中矿物元素含量及其生产性能的影响。处理1为基础日粮，处理2为低磷日粮添加250g/t植酸酶，处理3在基础日粮中添加1000g/t非淀粉多糖酶，处理4为低磷日粮添加250g/t植酸酶和1000g/t非淀粉多糖酶。结果表明：低磷日糖中添加植酸酶可提高N、P的表观利用率（P＜0．05），而非淀粉多糖酶有提高日粮N、P利用率的趋势（P＞0．05）；低磷日粮中添加植酸酶后胫骨灰分、Ca、P含量、血清中Ca、P、Cu、Zn和Fe等矿物元素含量的趋势（P＞0．05）；日粮中同时添加植酸酶和非淀粉多糖酶有促进日粮N和P利用率以及矿物元素吸收的趋势，但两者没有表现出显著的协同作用，日粮中应用2种酶后可减少粪中氮和磷的排泄量（P＜0．05，P＜0．01），有利于保护环境。     

植酸酶和木聚糖酶对仔猪钙、磷代谢及骨骼发育的影响

试验采用完全随机设计,将90头35日龄断奶仔猪分为5组,每组设3个重复,每个重复6头,研究在饲粮中添加植酸酶和木聚糖酶对断奶仔猪钙、磷代谢及骨骼发育的影响。5组分别饲喂：①玉米-豆粕基础饲粮（正对照组,PC）;②基础饲粮降低75％磷酸氢钙（负对照组,NC）;③负对照组饲粮＋植酸酶（植酸酶组,phy）;④负对照组饲粮＋木聚糖酶（木聚糖酶组,xy）;⑤负对照组饲粮＋植酸酶＋木聚糖酶（植酸酶-木聚糖酶组,pay—xy）,植酸酶的添加量为750U·kg^-1,木聚糖酶的添加量为4000U·kg^-1。结果表明：单独添加植酸酶和木聚糖酶或两者同时添加均使磷消化率极显著提高（P〈0.01）、排出量显著降低（P〈0．05）,血液磷浓度达到正常磷水平;添加酶的各组钙的消化率显著高于负对照组（植酸酶组、植酸酶一木聚糖酶组P〈0．01;木聚糖酶组P〈0．05）;添加酶的各组猪掌骨灰分均显著高于负对照组（P〈0．05）,但与正对照组无显著差异;添加植酸酶或木聚糖酶仔猪的酿骨强度均显著高于负对照组（P〈0．05）,但木聚糖酶组猪的跟骨强度仍显著低于采食正常磷饲粮的正对照组（P〈0．05）。因此,在断奶仔猪低磷饲粮中添加植酸酶或木聚糖酶都不同程度地促进了钙、磷的消化利用和骨骼生长,但两种酶同时添加没有显著的协同效应。     

低磷饲粮添加植酸酶对肉仔鸡生长性能及消化率的影响

以160只1日龄健康艾维因肉鸡为试材,研究在低磷饲粮中添加植酸酶（60 IU/kg）对其生长性能及养分消化率的影响。结果表明,添加植酸酶对肉仔鸡的日增重、耗料增重比、粗蛋白质和粗脂肪的消化率无显著影响（P〉0.05）,但能显著提高饲粮中钙和磷的消化率（P〈0.05）。     

不同无机磷水平日粮添加植酸酶对肉鸡生长性能和血清矿物质的影响

研究不同无机磷水平日粮添加植酸酶对肉鸡生长性能及血清矿物质的影响。选取1日龄肉鸡1 500只,以磷酸氢钙为磷源作为对照组,其余4个磷酸氢钙水平分别为对照组的75%、50%、25%、0,并添加植酸酶,各组钙磷比值在1.2～1.4。结果表明：本试验条件下,50%磷酸氢钙组日增重最高63.7 g/d,料重比最低为1.81。无磷酸氢钙组采食量111.4 g/d、日增重56.7 g/d均显著低于对照组（P〈0.05）。血清钙、血清无机磷各处理间差异不显著（P〉0.05）;血清碱性磷酸酶活性以无磷酸氢钙组活性最高2 667.80 U/L。血清铜、锌含量各处理间差异不显著（P〉0.05）。用血清碱性磷酸酶活性判断肉鸡钙、磷营养比用血清钙、血清磷更为敏感。添加植酸酶能提高肉鸡生长性能,但不能完全取代磷酸氢钙,以对照组磷酸氢钙水平的50%处理组（0～4周：Ca 0.76%,TP 0.54%;5～7周：Ca 0.70%,TP 0.53%）效果较好。     

植酸酶和柠檬酸对肉鸡生产性能的影响

以正常营养水平饲粮为对照,研究了在低营养水平饲粮中添加植酸酶(0,300 g/t)、柠檬酸(0,0.5%)对肉鸡生产性能和钙、磷利用率的影响.试验用225只1日龄黄羽肉鸡随机分为5个处理,每处理3个重复,每重复15只鸡进行6周试验.结果为饲粮营养水平降低6%可导致肉鸡日增重(ADG)和饲料利用率下降(P<0.05);在低营养水平日粮中,添加300 g/t植酸酶、0.5%柠檬酸的ADG和料肉比(F/G)与正常营养水平饲粮组差异不显著(P>0.05);各处理组的血清Ca,P,AKP活性及胫骨Ca,P差异不显著(P>0.05);腿病发生率各处理组差异不显著(P>0.05).添加300 g/t植酸酶、0..5%柠檬酸的处理组P排泄量显著低于对照组(P<0.05).植酸酶与柠檬酸合用能进一步提高生产性能和钙、磷利用率,能达到正常营养水平饲粮的效果.植酸酶与柠檬酸合用存在协同效应.     

阿莫西林在猪血清和组织液中对金黄色葡萄球菌的半体内药动-药效同步模型的研究#br#

 【目的】为合理应用阿莫西林治疗猪金黄色葡萄球菌感染。【方法】采用了体内药动和体外药效联合的方法研究了阿莫西林在血清和组织笼液中抗金黄色葡萄球菌的活性。【结果】体外测定,阿莫西林在血清和组织笼液中对猪金黄色葡萄球菌的MIC均在0.2 µg&#8226;mL-1＜MIC＜0.4 µg&#8226;mL-1的范围之内。如果在血清和组织液中添加更多的细菌,则需要高于MIC药物浓度才能能持续抑制细菌的生长。猪按10 mg&#8226;kg-1的剂量肌内注射阿莫西林后,在血清中,半效浓度（EC50）为143.63±54.35,即血清药物浓度为2.39 μg&#8226;mL-1时可产生50%最大效应。在组织液中,半效浓度（EC50）为29.61±5.07,即组织液药物浓度为0.49 μg&#8226;mL-1时可产生50%最大效应。【结论】临床上选择阿莫西林治疗猪金黄色葡萄球菌感染时,用药的剂量和间隔应根据实际情况确定,当治疗猪金黄色葡萄球菌轻度感染时,建议给药方案可设定为10 mg&#8226;kg-1体重的剂量进行颈部肌内注射,给药间隔为2次/日。当治疗重度感染时由于体内MIC的升高,体内药物维持抗菌时间减少,必须增加给药次数,可设为3次/日,必要时可增加为4次/日。     

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)。     

Nonphytate Phosphorus Requirement and Efficacy of a Genetically Engineered Yeast Phytase for Yellow Broilers at 22- to 42-d-Old Age

An experiment was conducted to investigate the requirement of nonphytate phosphorus (OP) and efficacy of a genetically engineered yeast phytase (PHY A) for Lingnan yellow broilers from 22- to 42-d-old age. A total of 1320 1 -d-old male chicks were randomly divided into 11 dietary treatment groups, which consisted of 4 replicate floor pens with 30 birds per pen.The control group (treatment 1) was fed with basal diet of nPP 0.08% without dicalcium phosphate or phytase supplementation. Dietary levels of nPP were 0.16, 0.24, 0.32, 0.40, 0.48, and 0.56%, respectively, for treatments 2 to 7,through addition of dicalcium phosphate (chemistry grade) to the basal diet. Diets of treatments 8 to 11 were supplemented with PHY A at 200, 400 and 600 U kg-t, a commercial phytase product (PHY B) at 400 U kg-1 level, respectively. The birds in 0.32-0.56% nPP groups gained more than those of the other groups (P<0.05). The nPP supplementation significantly improved feed intake (P<0.05). The feed gain ratio was significantly decreased by 0.40% nPP diet compared to the control birds (P<0.05). The level of 0.48% nPP was required for optimum tibia development. The additions of PHY A at 400 and 600 U kg-1 level and PHY B all significantly improved ADG (P<0.05), ADFI (P<0.05), and dry defatted tibia weight (P<0.05).Similarly, the percentage of tibia ash was increased by 600 U kg-1 PHY A supplementation (P<0.05). The requirement of nPP for maximal ADG and highest percentage tibia ash both was 0.40%. The phosphorus equivalency value of PHY A was estimated as 685 U kg-1 for male yellow broilers of 22- to 42-d-old age.     

Performance and Nutrient Utilization of Layers Fed Diet Supplemented with Microbial Phytase and Cellulase

1　Introduction　　The majority of the P in cereal grains and oilseed meals is organically bound as phytic acid orphytate.Phytate has potential to form insoluble complexes with protein and minerals such as P and Ca ,Cu ,Fe ,Mn ,Zn 〔1,2〕,which can negatively affect availabilities and digestibilities of minerals,protein or aminoacids〔3 ,4〕.Furthermore,phytate is also able to bind endogenous proteases such as trypsin and chymotrypsinin the gastrointestinal tract〔5〕,and these complexes ma…     

植酸酶对仔猪生长性能和消化率的影响

[目的]研究植酸酶对仔猪生长性能和饲料中各种成分消化率的影响。[方法]以40日龄64头杜大长仔猪为试材,将其随机分为4组,试验组分别添加1 0006、00和300 IU/kg的植酸酶,未添加的为对照,采用全收粪法测定饲料中各种成分的消化率。[结果]添加1 000和600 IU/kg植酸酶试验组的平均日增重分别为692和683 g,显著高于对照组和添加量为300 IU/kg的试验组;添加600 IU/kg植酸酶试验组的磷消化率由对照组的52.89%提高到62.78%(P<0.05),而且粗蛋白、灰分和钙的消化率都有显著提高(P<0.05);植酸酶的最适添加量确定为600 IU/kg。[结论]在饲料中添加一定量的植酸酶,能促进仔猪生长,提高日增重和饲料转化率,而且能显著提高饲料中粗蛋白、灰分、钙和磷的消化率。     

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.     

植酸酶对獭兔生产性能和矿物质排泄量的影响

试验研究了低磷日粮中添加植酸酶对獭兔生产性能和矿物质排泄量的影响。选用 3月龄左右体重相近的健康獭兔 5 0只 ,随机分为 5组。Ⅰ组为基础日粮组 (负对照 ) ,Ⅱ、Ⅲ、Ⅳ组为添加 4 0 0、6 0 0、80 0U kg植酸酶组 ,Ⅴ组为添加 1 8%磷酸氢钙组 (正对照 )。结果表明 :(1)添加植酸酶可以提高獭兔的日增重 (P <0 0 5 ) ,对日采食量和料肉比无显著影响 (P >0 0 5 )。(2 )添加植酸酶可显著降低獭兔粪中磷的排泄量 ,对粪中钙、铜、铁、锌、锰的排泄量均无显著影响 (P >0 0 5 )。但随着植酸酶水平的升高 ,粪铜含量呈上升趋势 ;粪钙、锌、锰的含量有所降低 ;粪铁含量无规律性变化趋势。     

不同植酸酶添加水平对肉仔鸡生产性能的影响

采用单因子随机分组试验设计,将120羽艾维茵肉仔鸡初生母雏随机分为4组(每组30只,3个重复),在低磷、低钙(非植酸磷0.28%、钙0.80%)的玉米-大豆粕-鱼粉型饲粮基础上,比较了4个植酸酶添加水平400、500、6007、50 FTU/kg的饲喂效果.结果表明,各组间0-3周、3-6周和0-6周的所有增重指标均无显著差异(P>0.05),但400 FTU/kg添加组0-3周的末重(P=0.352)、增重(P=0.356)和耗料量(P=0.089)均有小于其他各组的趋势;500 FTU/kg添加组全期增重呈现较好的趋势(P=0.361).750 FTU/kg添加组的死淘率最低(10%);500 FTU/kg组未发生腿病.各组间胫骨相对重和脱水脱脂胫骨灰分含量的差异不显著(P>0.05).400、600FTU/kg组腹脂率(P=0.216)和5007、50 FTU/kg组胸肌率(P=0.282)呈较高的趋势.各组间血浆Hyp含量差异不显著(P>0.05);400FTU/kg组(P<0.01)、500 FTU/kg和600 FTU/kg组(P<0.05)血浆Ca浓度均显著高于750 FTU/kg组;500 FTU/kg组血浆P含量显著高于750 FTU/kg组(P<0.05).综合各项指标,植酸酶适宜添加量为500 FTU/kg.     

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）。     

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.     

红三叶异黄酮对肉鸡生长性能的影响

选用200羽健康一日龄艾维菌肉仔鸡(公母混养),采取单因子随机化设计,随机分成5组,每组4个重复(每个重复10羽).对照组饲喂基础日粮,试验Ⅰ组、试验Ⅱ组、试验Ⅲ组和试验Ⅳ组在基础日粮中分别添加5,10,20,30mg·kg~(-1)的红三叶异黄酮.试验期为49d.结果表明:日粮中添加红三叶异黄酮可改善肉鸡的平均体增重、平均日采食量及料重比;显著提高公鸡血清中T3、T4水平(p<0.1),适当提高母鸡血清的T3水平(p>0.1);明显降低公鸡血清中的尿素氮含量(p<0.05),适当改善母鸡血清尿素氮水平(p>0.1);显著提高公鸡血清中的碱性磷簸酶水平(p<0.1),在一定程度上增加母鸡血清碱性磷酸酶水平;肉鸡基础日粮中添加5～20mg·kg~(-1)红三叶异黄具有较好的促生长效果.