日粮添加半胱胺对红羽肉鸡生长性能的影响

选择1日龄红羽肉鸡60只,随机分为4组,每组15只。对照组(Ⅰ组)饲喂基础日粮,试验组(Ⅱ、Ⅲ和Ⅳ组)在基础日粮中分别添加100、150、200 mg/kg的半胱胺(CS),试验期21 d,研究CS对红羽肉鸡生长性能的影响。结果表明:在肉鸡饲养过程中,在基础日粮中适量添加CS盐酸盐,可取得较好的养殖经济效益,但添加量不宜超过100 mg/kg,最适添加比例还有待进一步研究。     

陈皮苷制剂对肉鸡屠宰性能的影响研究

研究旨在探讨日粮中添加陈皮苷制剂对AA肉鸡屠宰性能的影响。试验选用200羽1日龄健康AA肉鸡,采用单因子随机分组试验设计分为5个处理,每个处理4重复,每个重复10羽鸡,5个处理分别饲喂基础日粮和含50、100、150和200 mg/kg陈皮苷制剂的试验日粮。结果表明:在1-14日龄阶段,当陈皮苷制剂添加量达到200 mg/kg时肉鸡的半净膛率和全净膛率显著高于对照组(P0.05),在15-28日龄阶段,当陈皮苷制剂添加量达到150 mg/kg时,半净膛率显著低于对照组(P0.05),在29-42日龄阶段,当添加量为150和200 mg/kg时,全净膛率相比对照组分别提高1.4%和1.2%(P0.05)。由此可知,陈皮苷制剂可在一定程度上提高肉鸡的屠宰性能,陈皮苷制剂在肉鸡日粮中的适宜添加量为200 mg/kg。     

酵母细胞壁在白羽肉鸡生长性能及免疫功能方面的效应

为了研究酵母细胞壁对白羽肉鸡生长性能指标以及新城疫抗体水平的影响,试验选用1日龄科宝肉鸡432羽,随机分为6个处理组,每个处理组6个重复,每个重复12羽。对照组A饲喂基础日粮,B组饲喂含金霉素(50 mg/kg)的基础日粮,C、D、E、F组饲喂添加不同含量(0.5、1、2、10 kg/t)的酵母细胞壁的基础日粮。结果表明:日粮中添加酵母细胞壁能提高肉鸡的生长性能,出栏体重较对照组分别提高6.16%、9.45%、5.09%、1.09%;同时酵母细胞壁可提高肉鸡的新城疫抗体水平和免疫器官指数,增强肉鸡免疫水平。在本试验条件下,添加1 kg/t酵母细胞壁,增重及抗体水平最高。     

日粮维生素E水平对AA肉鸡免疫器官发育的影响

目的:本研究旨在探讨日粮维生素E水平对AA鸡免疫器官发育的影响。方法:选用1 d健康AA肉鸡母鸡160羽,随机分为试验组和对照组共5个处理,每个处理4个重复,每个重复8羽,试验期为42 d。对照组饲喂基础日粮,试验组在基础日粮中分别添加25、50、75、100 mg/kg的维生素E。饲养期间每双周周末对各组AA肉鸡屠宰并称取胸腺、脾脏和法氏囊的重量,计算免疫器官指数。结果:试验结果表明,第2周时,日粮中添加75 mg/kg维生素E脾脏指数比对照组提高了16.67%(P>0.05),100 mg/kg时胸腺指数比对照组提高了13.04%(P>0.05)。第4周时,日粮中添加50 mg/kg维生素E脾脏指数比对照组提高了64.71%(P>0.05)。第6周时,日粮中添加25 mg/kg维生素E胸腺指数和脾脏指数分别比对照组提高了38.71%(P<0.05)和42.86%(P>0.05),100 mg/kg维生素E胸腺指数和法氏囊指数分别比对照组提高了45.16%(P<0.05)和7.69%(P>0.05)。结论:日粮中添加维生素E对肉鸡免疫器官的发育没有显著影响,但能够具有促进其生长发育的趋势。     

添加不同水平有机硒对红羽肉鸡生长和饲料报酬的影响

本试验通过研究蛋氨酸硒(Se-Met)对红羽肉仔鸡生产性能、饲料报酬的影响来探讨红羽肉仔鸡有机硒(蛋氨酸硒)的适宜添加量.选择1日龄红羽肉雏鸡180只,分为4组,分别饲喂在玉米-豆粕型基础日粮中分别添加蛋氨酸硒0、0.1、0.3、0.5 mg/kg的试验日粮.试验结果表明:在0～21日龄,0.1 mg/kg的蛋氨酸硒添加量效果最好,可提高日增重17.29%;不同蛋氨酸硒添加水平对红羽肉仔鸡胴体特性无显著影响(P＞0.05);可显著提高红羽内仔鸡的胸肌率与腿肌率(P＜0.05),降低红羽肉鸡的皮下脂肪厚与肌间脂肪宽.     

肉鸡玉米-豆粕型日粮中最佳Zn元素的添加水平研究

该试验研究了肉鸡玉米-豆粕型日粮中最佳Zn元素的添加水平。384只1日龄肉仔鸡随机分布到各试验日粮处理组，饲养期为21d。试验处理如下：在玉米-豆粕型基础日粮中（Zn含量为28．32mg／kg日粮）添加ZnSO4·7H2O形式的Zn，添加量分别为0、20、40、60、80、100、120和140mg／kg日粮。每个处理6个重复，每个重复8只鸡。     

蛋氨酸铬对肉鸡生长、脏器指数及血液生化指标的影响

试验旨在研究日粮中添加蛋氨酸铬对肉鸡生长、脏器指数及血清生化指标的影响,为确定日粮中蛋氨酸铬的适宜添加量提供科学依据。试验选用1日龄AA肉鸡528只,设4个处理,每个处理4个重复,每个重复33只。对照组饲喂玉米-豆粕型基础日粮,其它处理组饲喂分别在基础日粮中添加蛋氨酸铬0.1 mg/kg(Ⅰ组)、0.2 mg/kg(Ⅱ组)、0.6 mg/kg(Ⅲ组)的日粮(以Cr3+计),试验期49 d。结果表明:蛋氨酸铬能显著降低饲料消耗(P<0.05),但对肉鸡各日龄段平均体重、料重比和成活率影响差异均不显著(P>0.05)。除能显著降低心脏相对重量(P<0.05)外,日粮中添加蛋氨酸铬对肉鸡其它脏器相对重量影响差异均不显著(P>0.05)。日粮中添加蛋氨酸铬对血液生化指标影响显著(P<0.05)。因此,日粮中补充蛋氨酸铬对肉鸡生产性能、脏器指数影响不明显;但对血液生化指标影响显著,建议日粮中蛋氨酸铬添加量以0.2 mg/kg为宜。     

葡萄糖氧化酶对白羽肉仔鸡生长性能、养分代谢的影响

本试验研究了葡萄糖氧化酶对白羽肉仔鸡生产性能、养分代谢和肠道组织结构的影响,选择200只体重接近、健康的1日龄罗斯308白羽肉仔鸡,随机分为4个试验组,每试验组5个重复,每个重复10只,试验分为前期(1-21d)和后期(22-42d)两个阶段。试验分4种日粮,对照组为基础日粮(玉米豆粕型),处理1、2、3组分别在基础日粮中添加葡萄糖氧化酶50U/kg、100U/kg、200U/kg。结果表明:与对照组相比,添加100、200U/kg葡萄糖氧化酶可显著提高肉鸡全期日增重、降低耗料增重比(P0.05),显著提高干物质、粗蛋白质利用率及表观代谢能(P0.05);葡萄糖氧化酶添加200U/kg可显著降低回肠pH(P0.05)。     

饲粮中添加槲皮万寿菊素对肉鸡生长性能、养分表观消化率和抗氧化能力的影响

本试验旨在探究饲粮中添加槲皮万寿菊素对肉鸡生长性能、养分表观消化率和抗氧化能力的影响。选取1日龄健康爱拔益加(AA)肉鸡480只,随机分为4个组,每组6个重复,每个重复20只。对照组饲喂基础饲粮,试验组饲喂在基础饲粮中分别添加10、50和100 mg/kg槲皮万寿菊素的试验饲粮。试验期42 d,分为前期1～21日龄和后期22～42日龄2个阶段。结果表明：1)与对照组相比,饲粮添加50和100 mg/kg槲皮万寿菊素显著提高了肉鸡42日龄体重和1～42日龄平均日增重(ADG)(P<0.05),显著降低了1～21日龄、22～42日龄和1～42日龄料重比(F/G)以及1～42日龄平均日采食量(ADFI)(P<0.05)。2)与对照组相比,饲粮添加10和50 mg/kg槲皮万寿菊素分别显著提高了肉鸡粗脂肪和粗蛋白质的表观消化率(P<0.05)。3)与对照组相比,饲粮添加50和100 mg/kg槲皮万寿菊素显著提高了肉鸡21和42日龄血清谷胱甘肽过氧化物酶(GSH-Px)活性(P<0.05);饲粮添加10和50 mg/kg槲皮万寿菊素显著提高了肉鸡肝脏GSH-Px活性(P...     

饲粮不同硒水平对22～42日龄黄羽肉鸡生长性能、抗氧化指标的影响

试验旨在研究饲粮不同硒水平对22~42日龄黄羽肉鸡生长性能、抗氧化指标的影响,从而确定快大型黄羽肉鸡饲养中期的最适硒水平。选用22日龄健康、发育良好的快大型岭南黄羽肉公雏鸡1 200只,根据体重随机分为5个组,每组6个重复,每个重复40只,试验组1(对照组)为基础日粮组(硒含量0.037 mg/kg),试验组2、3、4、5饲粮则在基础日粮中分别添加0.075、0.15、0.225、0.30 mg/kg硒,试验期为21 d。结果表明:饲粮添加不同水平硒对试验鸡生长性能无显著影响(P0.05);各硒添加组血浆、红细胞和肝脏谷胱甘肽过氧化物酶(GSH-Px)活力显著高于对照组(P0.05),饲粮添加不同水平硒对试验鸡血浆和肝脏丙二醛(MDA)含量无显著影响(P0.05)。综合考虑,22~42日龄黄羽肉鸡饲粮硒适宜水平为0.337 mg/kg。     

电感耦合等离子-质谱法测定饲料中钠、镁、铬、锰、铁、铜、锌、砷、硒、镉和铅

应用电感耦合等离子-质谱技术(ICP-MS),建立饲料中钠、镁、铬、锰、铁、铜、锌、砷、硒、镉和铅等元素的测定方法。对饲料样品的前处理方法、仪器工作参数和11种元素标准曲线进行优化;并以加标回收、分析方法比对和重复测试说明方法的准确性和精密性。方法在0～1 000 ng/ml范围内线性良好,仪器检出限为0.557 7～5.072 ng/ml,具有良好的精密度,其回收率在88.1%～104.4%之间,相对标准偏差小于5.0%。同时与原子吸收和原子荧光方法进行比对,测定结果相近。所建立的方法简单、快速,可替代原子吸收和原子荧光方法测定饲料中的11种金属元素,为饲料的质量控制提供理想的元素分析方法。     

Supplementation of broodmares with copper, zinc, iron, manganese, cobalt, iodine, and selenium

In experiment 1, 6 pregnant mares received a concentrate that contained a trace mineral premix that provided 14.3 mg Cu, 40 mg Zn, 28 mg Fe, 28 mg Mn, 0.08 mg Co, 0.16 mg I, and 0.16 mg Se/kg concentrate (group A). Seven mares received the same concentrate plus 502 mg Zn and 127 mg Cu once daily (group B). No differences (P > .05) in foal growth data, or Cu, Zn, and Fe concentrations of mare milk, mare serum, or foal serum were observed. In experiment 2, 6 pregnant mares received the same concentrate as group A (group C), and 8 mares received the same concentrate fortified with 4× the trace mineral premix (group D). Group C mares had higher serum Zn concentration at 1 day (P < 0.01) and 56 days (P < 0.04). Group C mares had higher milk Fe concentration at 28 days (P < .01), and group D mares had higher milk Cu concentration at 56 days (P < .01). Group C foals had higher serum Cu concentration at 14 days (P < .03). The results from this study provide no evidence to indicate that supplementing late gestating and lactating mares with higher dietary trace mineral levels than those recommended currently by NRC has any influence on foal growth and development, or on the Cu, Zn, and Fe concentrations of the mare milk, mare serum, or foal serum.     

Comparisons of Angus, Charolais, Galloway, Hereford, Longhorn, Nellore, Piedmontese, Salers, and Shorthorn breeds for weight, weight adjusted for condition score, height, and condition score of cows

Breed differences for weight (CW), height (CH), and condition score (CS) were estimated from records (n = 12,188) of 2- to 6-yr-old cows (n = 744) from Cycle IV of the U.S. Meat Animal Research Center's Germplasm Evaluation (GPE) Program. Cows were produced from mating Angus and Hereford dams to Angus, Hereford, Charolais, Shorthorn, Galloway, Longhorn, Nellore, Piedmontese, and Salers sires. Samples of Angus and Hereford sires were 1) reference sires born from 1962 through 1970 and 2) 1980s sires born in 1980 through 1987. The mixed model included cow age, season of measurement and their interactions, year of birth, pregnancy-lactation code (PL), and breedgroup as fixed effects for CW and CS. Analyses of weight adjusted for condition score included CS as a linear covariate. The model for CH excluded PL. Random effects were additive genetic and permanent environmental effects associated with the cow. Differences among breed groups were significant (P < 0.05) for all traits and were maintained through maturity with few interchanges in ranking. The order of F1 cows for weight was as follows: Charolais (506 to 635 kg for different ages), Shorthorn and Salers, reciprocal Hereford-Angus (HA) with 1980s sires, Nellore, HA with reference sires, Galloway, Piedmontese, and Longhorn (412 to 525 kg for different ages). Order for height was as follows: Nellore (136 to 140 cm), Charolais, Shorthorn, Salers, HA with 1980s sires, Piedmontese, Longhorn, Galloway and HA with reference sires (126 to 128 cm). Hereford and Angus cows with reference sires were generally lighter than those with 1980s sires. In general, breed differences for height followed those for weight except that F1 Nellore cows were tallest, which may in part be due to Bos taurus-Bos indicus heterosis for size.     

液相色谱-串联质谱法测定动物尿液中11种β-受体激动剂残留量的不确定度评估

采用液相色谱-串联质谱法测定动物尿液中11种β-受体激动剂残留量,对标准溶液、体积、质谱峰面积、浓缩过程及回收率等测定不确定度因素进行了分析,通过评定各不确定度分量及标准不确定度,得出11种β-受体激动剂的扩展不确定度在0.7 ～ 1.1 ng/mL范围内.由各因素对合成不确定度的贡献比分析可知,影响较大的因素为试验回收率及标准溶液浓度.     

Granulocyte isolation from whole blood of goat, sheep, cattle, horse, dog, pig, and man

A simple two step procedure for the isolation of caprine, ovine, bovine, equine, canine, porcine and human peripheral blood granulocytes is described. After enrichment of granulocytes by centrifugation, contaminating erythrocytes are lysed hypotonically. Recovery, purity, and viability of the granulocyte suspensions are determined. FACScan analysis of the cell suspensions measuring cellular size by forward and sideward light scatter is compared with the corresponding analysis of whole blood leukocytes. Constituencies of the isolated cell suspensions and loss of granulocyte subpopulations through isolation procedure is discussed with regard to granulocyte function assays.