日粮中添加含硒生长素对肉仔鸡成活率及增重的影响

选用８００只１日龄艾维茵肉用仔鸡，随机分成４组（第１组为对照组）。试验采用玉米＝－豆饼型基础日粮，各组日粮含硒生长素的添加水平分别为０．０．１５％．０．２５％．０．３５％。试验期８周。试验结果表明，日粮中添加０．２５％的含硒生长素组（第３组），鸡成活率最高，增重快，显著高于其他组（Ｐ＜０．０１）；添加０．３５％的含硒生长素组（第４组），鸡发生了慢性硒中毒，成活率及增重显著低于第３组。由此认为，日粮     

肉仔鸡日粮中添加补益生长素效果探讨

在肉仔鸡日粮中分别添加0.5%、1%和2%由黄荆、黄芪、白术、紫菊、山药、常春藤、四季青、白芍、陈皮、甘草配成的补益生长素进行饲喂效果试验研究。结果表明,含1%补益生长素的试验2组比未添加补益生长素的对照组以及含0.5%补益生长素的试验1组和含2%补益生长素的试验3组肉仔鸡平均日增重分别提高12.89%、10.24%和12.26%(P0.05),饲料增重比分别降低了12.91%、8.17%和9.59%(P0.05),日粮中分别添加0.5%和2%补益生长素的试验组与对照组差异均不显著(P0.05)。添加补益生长素以1%比例为佳,并能改善肉仔鸡生产性能。     

饲料中添加高铜或高锌对猪生长发育及其肉质的影响

选用24头60日龄健康断奶长白仔猪,随机分成3组:Ⅰ组饲粮中添加含150ppm铜的含硒生长素,Ⅱ组饲粮中添加含90ppm锌的含硒生长素,Ⅲ组(对照组)饲粮中添加仅含硒生长素。结果表明:Ⅰ组日增重780g,饲料报酬1:3.83,Ⅱ组的数值相应为790g,1:3.88,Ⅲ组为779g,1:3.87,组间差异不显著(P<0.05)。肝中Cu、Zn、Fe、Mn、Se五种元素含量提高最为明显,眼肌中次之,但均未超过以往报导的正常含量。肉品质16项指标测定,15项组间差异不显著(P>0.05):17种氨基酸总量Ⅰ组为61.707％,较Ⅲ组60.055％提高2.75％;Ⅱ组60.995％,较Ⅲ组提高1.57％;统计分析组间差异不显著。这一结果提示在猪全价配合饲料中添加高剂量的Cu或Zn,当日增重达到较高水平时,对生长发育及肉质无不良影响。     

日粮中硒水平对肉鸡成活率和生长性能的影响

本试验将420只肉食鸡随机分为7组，每个处理4个重复，每个重复15只鸡，第1组为空白对照组，第2～7组为试验组。鸡日粮以玉米-豆粕为基础配制成粉料，将1～7组鸡在基础日粮中分别添加0、0．025、0．050、0．075、0．100、0．125、0．200mg／kg的硒添加剂（以硒计），进行为期42d的饲喂试验。结果表明，随着日粮硒添加水平的提高肉鸡成活率和体增重都有增大的趋势，其中添加水平0．125mg／kg达最高值，21和42日龄体重分别为624g和2402g，与对照组相比较分别提高31．37％和49．38％，差异显著（P〈0．05），料重比则随硒添加量的增加而降低，硒添加水平进一步增加，鸡的生产性能和成活率均有降低趋势。     

日粮中添加柠檬酸对肉鸡生产性能的影响

将36只21日龄的艾维茵仔鸡,随机分成6组(第一组为对照组),试验采用玉米-豆饼型基础日粮,各组日粮柠檬酸添加水平分别是0、0.15%、0.25%、0.5%、1%、2%,试验期5周,研究了日粮柠檬酸水平对肉仔鸡生产性能的影响.结果表明,日粮中添加0.25%的柠檬酸,鸡增重最快;添加2%柠檬酸,可显著降低肉鸡增重;添加0.15%、0.25%柠檬酸.鸡的饲料报酬最高.添加柠檬酸对日粮有机物质的消化率有显著影响,其中添加0.25%柠檬酸鸡的蛋白质消化率最高.因此认为,日粮添加0.25%柠檬酸为适宜添加量,添加2%柠檬酸为其最大耐受量.     

富硒猪肉生产研究

为了研究富硒猪肉生产过程中饲粮硒适宜添加水平,试验选择208头平均体重60 kg的杜长大三元杂交大白猪,随机分为7组,分别饲喂基础饲粮(对照组)和添加两种来源(硒A、硒B)不同水平(0.15、0.25、0.35 mg/kg)的硒产品添加剂,饲喂3个月,测定其生产性能,每组屠宰3头测定胴体性状,取背最长肌、前腿肌和后腿肌进行硒含量检测。结果表明:硒B组添加水平为0.25 mg/kg硒的试验组平均日增重比硒水平为0.35 mg/kg的试验组高128 g(P0.05),而料重比显著低于硒水平为0.35 mg/kg的试验组0.42(P0.05);而在硒沉积测定时,在背最长肌中,添加0.25 mg/kg硒A组相比对照组提高26.9%(P0.05),在前腿肌中,添加0.35 mg/kg硒B组相比对照组提高27.8%(P0.05),在后腿肌中,添加0.35 mg/kg硒B组相比对照组提高28.2%(P0.05),两种来源硒对于各肌肉组织硒沉积方面无显著性差异。试验表明,饲粮中添加硒元素能改善猪的生产性能并提高硒在组织中的沉积,有利于富硒猪肉的生产。     

茶多酚对固始鸡免疫器官发育的影响

选取1日龄健康的固始鸡90只,按体重相近的原则,随机分成3组.即对照组、试验组Ⅰ、试验组Ⅱ(n=30,),对照组饲喂基础日粮,试验组在基础日粮中分别添加0.25%和0.50%的茶多酚,试验期为42 d.研究茶多酚对固始鸡免疫器官发育的影响.于2、4、6周龄每组屠宰10只固始鸡,称脾脏、法氏囊及胸腺重量,并计算免疫指教.结果表明,与对照组相比,日粮中添加0.25%的茶多酚,2周龄时固始鸡法氏囊增重显著(P＜0.05);日粮中添加0.50%的荼多酚,4周龄时固始鸡法氏囊增重显著(P＜0.05),6周龄时固始鸡胸腺增重显著(P＜0.05);对脾脏无显著影响.     

竹叶黄酮对济宁百日鸡早期增重及部分器官指数的影响

试验旨在研究添加不同浓度的竹叶黄酮对济宁百日鸡增重及部分器官指数的影响。选用1日龄济宁百日鸡200只,随机分为4个组,每组5个重复,每个重复10只;对照组饲喂基础日粮,试验组Ⅱ~Ⅳ分别在基础日粮中添加0.05%、0.25%和0.45%的竹叶黄酮,试验期4周。结果表明:与对照组比较,1周龄0.45%剂量组的肝脏指数极显著提高(P0.01)。3周龄0.45%剂量组的肝脏指数显著提高(P0.05),0.25%和0.45%剂量组的肌胃指数极显著提高(P0.01),0.05%剂量组的胸腺指数显著降低(P0.05)。4周龄0.05%剂量组肌胃指数极显著降低(P0.01),0.25%剂量组的心脏指数显著提高(P0.05),肝脏指数极显著提高(P0.01)。各试验组济宁百日鸡的周增重均有不同程度提高,4周龄0.25%剂量组显著提高(P0.05),而0.45%剂量组极显著提高(P0.01)。可见,日粮中添加一定量的竹叶黄酮能够提高济宁百日鸡早期的增重、肝脏指数、肌胃指数、心脏指数和周增重,并且不同程度降低胸腺指数。     

饲粮半胱氨酸水平对獭兔生产性能、氮代谢、毛皮品质及KAP6.1基因时序表达的影响

本研究旨在研究饲粮半胱氨酸水平对獭兔生产性能、氮代谢及毛皮品质和KAP6.1基因时序表达的影响.选取120只90日龄健康獭兔随机分为4组(每组30个重复,每个重复1只兔),对照组饲喂基础日粮,试验组饲喂基础饲粮中添加0.25％、0.35％、0.45％水平的半胱氨酸的试验饲粮,预饲期7d,正式期40 d.结果,饲粮半胱氨酸水平0.25％、0.45％组末重显著高于0％、0.35％组(P＜0.05).饲粮半胱氨酸水平0.35％、45％组采食量(P＜0.05)显著高于0％、0.25％组,对平均日增重、料重比无显著影响(P＞0.05)；半胱氨酸0.35％组食入氮、可消化氮极显著高于其他组(P＜0.01),0.45％组的沉积氮显著高于对照组(P＜0.05),对粪氮、尿氮、表观消化率、氮利用率、氮生物效价均无显著影响(P＞0.05)；饲粮半胱氨酸水平0.45％组处理40 d皮张面积显著大于其余各组(P＜0.05).饲粮半胱氨酸水平0.45％、0.35％组处理30 d被毛密度显著高于0％、0.25％水平组(P＜0.05),对皮张厚度无显著性影响(P＞0.05)；饲粮半胱氨酸水平0.45％处理20 d,KAP6.1基因在软骨、皮肤中表达量均显著高于其他组(P＜0.05),而对处理10、30、40 dKAP6.1基因在软骨、皮肤中表达量无显著影响(P＞0.05).综上所述,獭兔饲粮中半胱氨酸适宜添加量为0.45％,且110～120日龄使用效果最佳.     

百里香精油对麻花鸡生长性能、血清蛋白和细胞因子的影响

本试验旨在研究日粮中添加不同水平百里香精油对麻花鸡生长性能、血清蛋白和细胞因子的影响。选取1日龄麻花鸡768只,采用单因子试验设计,随机分为8组,每组4个重复,每个重复24只鸡。对照组饲喂基础日粮,试验Ⅰ~Ⅶ组在基础日粮中分别添加0.05、0.10、0.15、0.20、0.25、0.30和0.35 mg/kg百里香精油。试验期42 d,分1~21日龄(前期)、22~42日龄(后期)2个阶段。结果表明,与对照组相比,日粮中添加百里香精油对1~21日龄麻花鸡生长性能无显著影响(P>0.05),但试验Ⅱ~Ⅵ组可极显著提高22~42日龄麻花鸡平均日增重(P<0.01),试验Ⅲ、Ⅳ、Ⅵ组可显著降低22~42日龄麻花鸡料重比(P<0.05)。与对照组相比,试验Ⅱ组可显著降低42日龄麻花鸡血清中白蛋白含量(P<0.05),试验Ⅱ~Ⅴ、Ⅶ组可显著提高21日龄麻花鸡血清中球蛋白含量(P<0.05),试验Ⅱ、Ⅳ、Ⅴ组可显著降低21和42日龄麻花鸡血清中白蛋白/球蛋白比值(P<0.05)。与对照组相比,日粮中添加百里香精油对21和42日龄麻花鸡血清中白介素-4、肿瘤坏死因子-α和γ-干扰素含量均无显著影响(P>0.05),但试验Ⅶ组可显著提高42日龄麻花鸡血清中白介素-1含量(P<0.05)。综上所述,日粮中添加百里香精油可显著促进麻花鸡体内蛋白沉积,提高生长性能和增强γ-球蛋白和白介素-1细胞因子参与介导的免疫调节作用,建议生产中麻花鸡日粮中百里香精油的适宜添加量为0.10~0.25 mg/kg。     

香辛型中草药添加剂对肉仔鸡生长和屠宰性能的影响

选用120只21日龄肉仔鸡，随机分成对照组和试验组2组，每组3个重复，对照组饲喂基础日粮，试验组饲喂在基础日粮中添加0．5％香辛型中草药添加剂的日粮，经21天的饲喂试验，研究香辛型中草药添加剂对肉用仔鸡生长和屠宰性能的影响，结果表明：在肉用仔鸡日粮中添加香辛型中草药添加剂可显著提高肉用仔鸡的体重、平均日增重、腿肌率和胸肌pH值，显著降低腹脂率和皮脂厚。     

日粮蛋氨酸及赖氨酸水平对雌性肉仔鸡胴体组成的影响

本试验旨在探讨日粮蛋氨酸和赖氨酸水平对 3～ 6周龄艾维茵母鸡胴体组成及脂肪代谢的影响。试验采用 3× 5双因子试验设计 ,蛋氨酸设 3个水平 ( 0 32 % ,0 4 4% ,0 56 % ) ,赖氨酸设 5个水平( 0 7% ,0 85% ,1 0 % ,1 1 5% ,1 30 % ) ,一共形成 1 5个处理组。基础日粮由玉米、豆粕、花生粕、玉米蛋白粉等组成。含代谢能 1 2 73MJ/Kg ,粗蛋白 1 8 8% ,赖氨酸 0 7% ,蛋氨酸 0 32 %。试验末分别检测生产性能 ,屠宰性能及血液生化指标。结果表明 :日粮赖氨酸和蛋氨酸显著影响了肉仔鸡的胴体组成和脂肪代谢 (P <0 0 1 )。赖氨酸和蛋氨酸缺乏或过量 ,血浆尿酸、甘油三脂和极低密度脂蛋白浓度均呈上升趋势。日粮赖氨酸 ( 0 70 % )和蛋氨酸 ( 0 32 % )缺乏显著降低了肉仔鸡的体增重、胸肉率及全净膛率 (P<0 0 5) ,而腹脂沉积偏高。适度提高日粮赖氨酸和蛋氨酸水平可以提高全净膛率 ,胸肌率 ,降低腹脂沉积 ,从而改善胴体品质     

复合短链脂肪酸对肉仔鸡生产性能的影响及相关作用机制的探讨

试验旨在研究复合SCFAs对肉仔鸡生产性能的影响及其相关的作用机制。120只AA肉仔鸡随机分成2组(复合SCFAs添加组和对照组),每组6个重复,每个重复10只鸡。结果表明,与对照组相比,添加复合SCFAs组的肉仔鸡的体增重、耗料量、胰腺相对重量分别提高了4.4%、5.6%、16%(P<0.05),小肠淀粉酶和胰蛋白酶的活性分别提高了48.5%和37.3%(P<0.05),降低了十二指肠中大肠杆菌的数量(P<0.05)以及血清中葡萄糖和胰岛素的含量(P<0.05)。日粮中使用复合SCFAs可以提高肉仔鸡小肠消化酶活性,减少消化道中大肠杆菌的数量,改善肉仔鸡的生产性能。     

0～21和22～42日龄黄羽肉鸡可消化蛋氨酸需要量的研究

试验一和试验二分别选用1日龄和22日龄岭南黄鸡各2 000只和1 600只,按性别和体重分成10处理组(公、母鸡各5组),每组4重复栏,每栏50(试验一)和40只鸡(试验二)。2个试验均采用5(饲粮蛋氨酸水平)×2(性别)两因子试验设计,试验一和二分别设0.35%、0.40%、0.45%、0.50%和0.55%以及0.30%、0.35%、0.40%、0.45%和0.50%5个饲粮蛋氨酸水平。结果表明:随着饲粮蛋氨酸水平提高,0～21日龄和22～42日龄公、母鸡每日总蛋氨酸摄入量和真可消化蛋氨酸摄入量呈线性或二次曲线升高(P<0.05);0～21日龄公、母鸡的日增重呈二次曲线升高(P<0.05),0～21日龄和22～42日龄公、母鸡的饲料增重比呈二次曲线降低(P<0.05或0.1)。可见,在基础饲粮中添加适量蛋氨酸改善了黄羽肉鸡的生产性能。根据二次回归模型估测黄羽肉鸡获得最佳生产性能95%处的总蛋氨酸需要量和真可消化蛋氨酸需要量,0~21日龄母鸡为0.433%~0.435%和0.404%~0.406%,公鸡为0.445%~0.454%和0.416%~0.425%,22～42日龄母鸡为0.463%和0.437%,公鸡为0.375%和0.349%。     

Influence of Temperature on the Arginine and Methionine Requirements of Young Broiler Chicks

Two experiments were conducted with Ross × Ross broiler chicks in battery brooders from 7 to 21 d of age to determine the Arg and Met requirements of young broiler chicks at control (25°C) and warm (35°C) temperatures. In both experiments, 1-d-old broiler chicks were fed a corn and soybean meal based starter diet for 7 d. Six replications (2 replicates in each of 3 rooms per temperature) with 8 chicks each were used for each treatment. In experiment 1, the basal diet was based on corn (34.52%), whey (26.96%), corn gluten meal (16.53%), soybean meal (11.74%), and poultry fat (23% of CP and 3.20 kcal/g of ME_n). Six levels of Arg (0, 0.1, 0.2, 0.3, 0.4, and 0.5%), supplementing the basal diet containing 0.95% Arg, were the dietary treatments. A broken-line linear model was used to estimate chick Arg requirements. Based on body gain and feed conversion ratio (FCR) data, respectively, the Arg requirements of young Ross × Ross broiler chicks raised at 35°C were 1.15 ± 0.03% and 1.13 ± 0.02%, whereas those of chicks at 25°C were 1.26 ± 0.03% and 1.27 ± 0.02%. In experiment 2, the influences of temperature and dietary Arg on the Met requirements of young broiler chicks were investigated. The basal diet was based on corn (53.45%), soybean meal (37.72%), and poultry fat (23% of CP and 3.20 kcal/g of ME). Experiment 2 had a 6 × 2 factorial arrangement, with the basal diet (0.35% Met and 1.52% Arg) supplemented with 6 levels of dietary Met (0, 0.05, 0.1, 0.15, 0.2, or 0.3%) and 2 levels of dietary Arg (0 and 1.0%). When chicks were fed a corn-soybean meal basal diet containing 1.52% Arg, the Met requirements of young Ross × Ross broiler chicks raised at 35°C were 0.43 ± 0.02% and 0.43 ± 0.03%, whereas those of chicks at 25°C was 0.43 ± 0.01% and 0.48 ± 0.03%, based on body gain and FCR data, respectively. When Arg levels were increased to 2.52%, the Met requirement of young Ross × Ross broiler chicks was greater at both temperatures (P < 0.05). The requirements of chicks raised at 35°C were 0.50 ± 0.02% and 0.49 ± 0.02% and at 25°C were 0.59 ± 0.03% and 0.57 ± 0.02%, based on body gain and FCR data, respectively. Temperature and amino acid balance may both affect the amino acid requirements of broilers.     

Effect of dietary selenium on the development of Fusarium-induced tibial dyschondroplasia in broiler chickens

A trial was conducted to determine the effects of dietary level of selenium on the pathogenesis of Fusarium-induced tibial dyschondroplasia (FITD) in broiler chicks, and to assess the applicability of FITD as an animal model of Kashin-Beck disease of humans. Day-old female broilers were fed diets that were deficient in selenium (0.02 ppm Se), adequate in selenium (0.15 ppm Se), or generous in selenium (0.50 ppm Se). TDP-1, the toxic component of the fungus, was administered to 15 of 26 chicks in each dietary group starting at 1 week of age and continuing until the chicks were killed at 24-30 days of age. Plasma selenium levels and hepatic glutathione peroxidase activity were significantly lower in the selenium-deficient group than in other dietary groups; these parameters were not affected by treatment with TDP-1. The mortality rate of the TDP-1-treated selenium-generous group was significantly less than that in the other TDP-1-treated groups, but there were no differences in the incidence, severity, or character of the FITD lesions among the groups. Thus, the interaction of selenium and TDP-1 did not include an effect on FITD.     

Foot Ash as a Means of Quantifying Bone Mineralization in Chicks

Three studies were conducted to evaluate foot ash as an alternative method to quantify the degree of bone mineralization in broiler chicks. In Experiment 1, the objective was to evaluate whether degree of bone mineralization would be reflected by foot ash in broiler chickens at 14 d of age. Birds receiving 0.24, 0.32, or 0.40% of dietary available phosphorus (AP) demonstrated significant differences in foot ash (10.93, 13.46, and 15.45%, respectively). In Experiment 2, we determined that the time required for a foot sample to dry to a constant weight at 105°C was 48 h. In Experiment 3, the objectives were to compare the response of bone mineralization to dietary phosphorus levels as reflected by foot ash and tibia bone ash and to evaluate the effect of fat extraction on the determination of these parameters. Broiler chicks were fed graded levels of AP (0.25, 0.30, 0.35, and 0.40%) from 1 to 14 d of age. Significantly different responses between each dietary AP level could be detected by any method used. A significant linear response was observed between dietary AP and percentage of extracted or unextracted tibia or foot ash, with determination coefficients above 90% found for all 4 methods used. Results confirmed that the dietary phosphorus levels affected bone mineralization and that the degree of mineralization could reliably be reflected by foot ash. The assay was found to be as reliable as the tibia bone ash in reflecting degree of bone mineralization in chicks during the first 14 d of age. Fat extraction did not affect the reliability of either assay.     

1～3周龄雌性肉仔鸡精氨酸需要量

本试验旨在研究饲粮中精氨酸水平对l～3周龄雌性爱拔益加(AA)肉仔鸡的影响,并运用二次曲线模型进行需要量估计.试验选用540只1日龄雌性AA肉仔鸡,随机分成6组,每组5个重复,每个重复18只鸡.6个组饲粮精氨酸水平分别为1.000%、1.125%、1.250%、1.375%、1.500%和1.625%.结果表明:精氨酸...     

共轭亚油酸对肉仔鸡体组成和肉品品质的影响

本试验旨在探讨日粮添加共轭亚油酸(CLA)对肉仔鸡体组成和肉品品质的影响。240只1日龄肉仔鸡随机分配到4个日粮处理组(0%、0.25%、0.5%和1%CLA),每个处理6个重复,每个重复10只鸡。试验结果表明:42d时,0.5%和1%CLA组肉仔鸡胸肌率显著高于对照组(P<0.05),1%CLA组肉仔鸡42d腿肌率显著高于对照组,肉仔鸡的腹脂率在各处理之间没有显著差异(P>0.05),1%CLA组肉仔鸡胸肌粗蛋白质粗脂肪比显著高于对照组(P<0.05)。0.5%、1%CLA组肉仔鸡胸肌滴水损失和丙二醛(MDA)含量显著降低(P<0.05)。试验结果表明,CLA可改善肉仔鸡屠体性状,增加鸡肉系水力和延长货架存放时间。     

Effects of L-carnitine and niacin supplied by drinking water on fattening performance, carcass quality and plasma L-carnitine concentration of broiler chicks.

The present study was initiated to determine whether dietary supplemental L-carnitine and niacin affect growth performance, carcass yield, abdominal fat and plasma L-carnitine concentration of broiler chicks. One-day-old broiler chicks (COB500) were used in the experiment. A two by two factorial arrangement was employed with two levels (0 and 50 mg/l) of supplemental L-carnitine and two levels (0 or 50 mg/l) of supplemental niacin in drinking water as main effects. Body weight gain was significantly improved by L-carnitine, or L-carnitine + niacin supplementation during the first 3 weeks. However, supplemental L-carnitine and niacin did not change body weight gain during the last 3 weeks of the experimental period. Supplemental L-carnitine significantly improved feed intake during the first 3 weeks. Supplemental L-carnitine or niacin did not influence carcass weight, carcass yield and abdominal fat weight. L-carnitine content in the plasma was significantly higher in the groups receiving supplemental L-carnitine and L-carnitine + niacin. It is concluded that dietary supplemental L-carnitine or L-carnitine + niacin could have positive effects on body weight gain and feed intake during the early stages of growing. However, supplemental L-carnitine or L-carnitine + niacin were not of benefit regarding the complete growth period.