多种饲料添加剂类抗生素对猪源产气荚膜梭菌的抑菌效果研究

本试验目的在于研究多种不同饲料添加剂类抗生素对产气荚膜梭菌的抑菌试验,筛选出对产气荚膜梭菌抑菌效果强的药物,为饲料、养殖业临床上控制产气荚膜梭菌提供理论依据。试验选用喹乙醇、4%恩拉霉素、盐霉素、硫酸黏霉素、15%杆菌肽锌、黄霉素、吉他霉素和盐酸金霉素八种饲料常用抗生素添加剂,采用试管稀释法对猪源产气荚膜梭菌野毒株进行抑菌试验。试验结果表明:(1)恩拉霉素抑菌作用最强,其MIC为1.6μg/m L;(2)喹乙醇和15%杆菌肽锌抑菌作用较强,它们的MIC分别为4μg/m L和6μg/m L;(3)黄霉素、硫酸黏霉素、吉他霉素抑菌作用较弱,它们的MIC分别为40μg/m L、200μg/m L、300μg/m L;(4)盐霉素及盐酸金霉素对该产气荚膜梭菌野毒株几乎没有抑菌作用。由以上八种抗生素对产气荚膜梭菌的抑菌试验结果得出,八种抗生素对该产气荚膜梭菌野毒株均有不同程度的抑菌作用,而恩拉霉素对产气荚膜梭菌抑菌效果最强。     

饲用抗生素在雏鸡生产中应用效果的比较

<正>雏鸡早期良好的生长是获得健康、高度均匀鸡群的基础。在雏鸡生产管理中,合理地选择及科学地使用饲用抗生素可以起到调节肠道微生物菌群、提高雏鸡生长性能和成活率等作用。目前,黄霉素、金霉素、阿维拉霉素、安普霉素、吉他霉素等都是国内外雏鸡饲养中普遍采用的抗生素添加剂,其用量小、性能稳定、毒性小、无停药期的要求。     

饲粮中添加复合植物精油对断奶仔猪生长性能、血清生化指标及抗氧化性能的影响

本试验旨在研究饲粮中添加复合植物精油对断奶仔猪生长性能、血清生化指标、抗氧化性能及免疫性能的影响。试验选用396头35日龄平均体重为(9.60±0.30)kg的健康"杜×长×大"断奶仔猪,根据体重、性别及健康状况等均衡分布原则随机分为3组:抗生素组(基础饲粮+96 mg/kg延胡索酸泰妙菌素+75 mg/kg金霉素+200 mg/kg吉他霉素)、试验A组(基础饲粮+150 mg/kg复合植物精油)、试验B组(基础饲粮+200 mg/kg复合植物精油),每组6个重复,每个重复22头仔猪。试验期35 d。结果表明:1)与抗生素组相比,饲粮中添加200 mg/kg复合植物精油不仅显著提高仔猪平均日增重(P<0.05)、血清中总超氧化物歧化酶(T-SOD)活性和总抗氧化能力(T-AOC)(P<0.05),而且还能够显著提高仔猪血清中免疫球蛋白G(IgG)含量(P<0.05)。2)与抗生素组相比,饲粮中添加150 mg/kg复合植物精油能显著提高仔猪血清白蛋白含量(P<0.05)。综上所述,饲粮中添加200 mg/kg的复合植物精油具有增强断奶后仔猪健康、促进生长、提高机体抗氧化及免疫力的功效。因此,复合植物精油在断奶仔猪上具有潜在的利用价值。     

两种抗生素的效价比及其对甘农3号紫花苜蓿愈伤组织生长发育的影响

两种抗生素羧苄青霉素和头孢霉素对农杆菌LBA4404的抑菌效果及其对甘农3号紫花苜蓿愈伤组织的生长、体细胞胚分化的影响进行了研究。结果表明,羧苄青霉素的抑菌效果较好,适宜浓度为200~300 mg/L;在浓度200~400 mg/L的羧苄青霉素可促进芽分化;头孢霉素对甘农3号下胚轴离体培养的毒性大,浓度为600 mg/L时完全抑制芽分化。因此,羧苄青霉素为适宜抑菌剂,愈伤诱导阶段的适宜浓度为300 mg/L,体胚形成及芽诱导分化阶段的适宜浓度为200 mg/L。     

包膜丁酸钠颗粒对肉仔鸡生产性能的影响

本试验在基础日粮基础上,分别设计添加50%吉他霉素组、500 mg/kg包膜丁酸钠组、300 mg/kg包膜丁酸钠组+50%吉他霉素组和对照组5种不同添加组合的饲料饲喂肉仔鸡,以研究腐植酸对肉仔鸡生产性能的影响。试验结果表明:其中对照组的料肉比最高,从高到低依次是对照组抗生素组500 mg/kg包膜丁酸钠组300 mg/kg包膜丁酸钠组300 mg/kg包膜丁酸钠组+抗生素组。从本试验来看,包膜丁酸钠具有促进肉仔鸡生产性能提高的效果,肉仔鸡配合日粮中添加300 mg/kg包膜丁酸钠组钠的效果最佳,同时与50%吉他霉素具有配伍作用。     

不同抗生素配伍对断奶仔猪生长性能影响研究

选用产期相近、体重相近、健康状况良好的断奶仔猪(20日龄)128头,随机分成4个处理,每个处理4个重复,每个重复8头仔猪。研究在基础饲粮中分别添加泰乐菌素50mg/kg(泰乐菌素0.07kg)+硫酸抗敌素(0.4kg)、金霉素15%(2.0kg)+喹乙醇(0.1kg)、吉他霉素50mg/k(g0.1kg吉尔康500)+喹乙醇(0.1kg)、吉他霉素50mg/k(g0.1kg吉尔康500)+硫酸抗敌素(0.4kg)对断奶仔猪生产性能的影响。试验结果表明,添加吉他霉素50mg/kg(0.1kg吉尔康500)+喹乙醇(0.1kg)效果优于其它各组,而且经济效益最好,腹泻率最低。     

复合益生菌与金霉素配伍抑制金黄色葡萄球菌生长的研究

为降低抗生素的使用剂量,利用正交试验,研究四种益生菌与金霉素配伍对金黄色葡萄球菌生长的抑制作用。结果表明,复合益生菌抑制金黄色葡萄球菌的最佳组合为:枯草芽孢杆菌??酵母菌??乳酪杆菌??粪肠球菌=4??1??4??1;单独复合益生菌对金黄色葡萄球菌的抑制作用与200~300 mg/kg的金霉素相当。随着金霉素浓度的提高,无论是单一的金霉素或是其与益生菌的复合物,其抑菌作用逐渐增强(P0.05)。当150 mg/kg金霉素与益生菌配合后,其抑菌效果与单一(400~500 mg/kg)金霉素作用相当。由此可知,低浓度金霉素与复合益生菌配合后,可以达到高浓度金霉素的抑菌效果。     

液相色谱—串联质谱法测定猪配合饲料中吉他霉素

采用液相色谱-串联质谱仪测定猪配合饲料中吉他霉素。试样中的吉他霉素经20/80(V/V)甲醇/水提取,取部分上清液稀释,用美国waters公司生产的固相萃取柱(6cc/200mg Oasis HLB)净化,氮气吹干,初始流动相复溶,上液相色谱-串联质谱仪测定,保留时间和离子丰度比定性,外标法定量。本方法中吉他霉素检测限为0.01mg/kg、定量限为0.05mg/kg。吉他霉素的线性范围为5~200 ng/mL,相关系数r大于0.999。在0.05~50 mg/kg的添加水平上,吉他霉素的平均回收率为63.3%~106.6%,相对标准偏差为1.6%~10.3%。     

耐受高浓度吉他霉素的发酵乳杆菌的诱变筛选

试验以一株发酵乳杆菌为出发菌株,通过不同浓度吉他霉素诱变,从而筛选出一株耐受60mg/L吉他霉素的乳酸菌。该株乳酸菌具有耐受吉他霉素、性状稳定及容易在猪肠道定殖的优点。通常饲料中吉他霉素的添加量为30mg/kg,试验的产物菌株在该浓度下可完全不受抑制,从而保证肠道内乳酸菌群在抗生素使用过程中不被破坏。     

吉他霉素、泰乐菌素和金霉素对耐药性大肠杆菌生长代谢和耐药性累积的影响

利用体外诱导猪源大肠杆菌产生耐药性的方法,比较研究了防病促生长剂量的吉他霉素(20mg/L)、金霉素(100mg/L)、泰乐菌素(20mg/L)对耐药型和野生型致病大肠杆菌耐药性累积、蛋白质氨基酸代谢、能量利用和代谢调节的影响。结果表明:产生耐药性后的大肠杆菌在防病促生长剂量环境中继续培养,不影响最小抑菌值(MIC)和最小杀菌浓度(MBC);比野生型大肠杆菌显著或极显著提高菌液总蛋白和总AA产量(P<0.05)、乳酸产量(P<0.05)、Na+-K+-ATP酶活性(P<0.05)和NO产量(P<0.01)。由此可得出,猪源大肠杆菌产生耐药性以后,继续使用饲用抗生素不会进一步增加耐药性,但显著增强能量、蛋白代谢。     

The compatibility of the new ionophore-coccidiostats with other chemotherapeutics in broilers

The compatibility of Salinomycin, Narasin or Maduramycin with Tiamulin, Erythromycin, Tylosin, Kitasamycin, Flumequine, Sulfachlorpyrazine or Sulfaquinoxaline was tested in cockerels in three experiments. It was found that Salinomycin and Narasin are incompatible with Tiamulin, Erythromycin, Sulfachlorpyrazine and Sulfaquinoxaline. The effect of incompatibility was shown more markedly with the administration of Salinomycin than with Narasin. Maduramycin was also shown as incompatible with Tiamulin although this interaction was nowhere near as severe as in the case of Salinomycin or Narasin. It caused a significant weight gain depression without mortality. Because of the significant weight gain depression, however, the administration of Tiamulin in the presence of Maduramycin in feed will not be recommended. At the same time, Maduramycin proved to be fully compatible with Erythromycin, Sulfachlorpyrazine and Sulfaquinoxaline. All three anticoccidials tested showed total compatibility with Tylosin, Kitasamycin and Flumequine.     

黄霉素和瘤胃素对肉牛血液生理生化指标的影响

本研究旨在探讨黄霉素和瘤胃素用作饲料添加剂时,对肉牛血液生理生化指标的影响。选择年龄、体重相近(305±26.54kg)的40头健康未去势公牛作为试验动物,随机分为4组,第一组饲喂300mg/d.头黄霉素,第二组饲喂300 mg/d.头瘤胃素,第三组饲喂300 mg黄霉素+300mg瘤胃素/d.头,第四组为对照组。结果表明:瘤胃素和黄霉素对肉牛血液生理指标没有显著的影响。     

富乐旺对早期断奶仔猪生长性能和腹泻的影响

150头仔猪被随机分为5组,每组30头,进行饲养试验,探讨富乐旺对断奶仔猪生产性能和腹泻的影响。试验结果表明:与对照组相比,试验组平均日增重升高其中10mg/kg、15mg/kg和20mg/kg富乐旺添加组差异显著(P<0.05);平均日采食量升高;饲料系数和腹泻率、腹泻频率及死亡率降低。     

糖萜素与黄霉素对早期断奶仔猪生产性能和肠道菌群的比较研究

选用21日龄左右健康无病、初重基本一致的杜长大猪进行饲喂试验，随机分为5组，每组3个重复，每重复8头猪，自由采食和自由饮水。试验设计为：第Ⅰ组为对照组，第Ⅱ、Ⅲ组在每千克基础日粮中分别加入250、500 mg糖萜素，第Ⅳ、Ⅴ组在每千克基础日粮中分别加入250 mg糖萜素+4 mg黄霉素、4 mg黄霉素。结果表明：①第Ⅱ、Ⅲ、Ⅳ、Ⅴ组的平均末重较对照组分别提高4.00%、12.30%、5.21%、2.64%，平均日增重第Ⅲ组显著高于对照组(P<0.05)。与第Ⅱ、Ⅴ组相比，第Ⅳ组可提高饲料转化率，表明糖萜素与黄霉素具有一定的协同作用。②盲肠中大肠杆菌，各试验组均有一定的抑制作用，尤其是第Ⅳ组效果最好；结肠、直肠中大肠杆菌，试验组Ⅱ、Ⅲ、Ⅳ显著低于对照组Ⅰ和Ⅴ（P<0.05），其中Ⅲ组大肠杆菌含量最低（P>0.05）。处理Ⅲ能显著增加盲肠中双歧杆菌数（P<0.05），处理Ⅳ能显著增加盲肠中乳酸杆菌数（P<0.05），各处理组与对照组相比，均能增加结肠和直肠中双歧杆菌数和乳酸杆菌数，但差异不显著（P>0.05）。     

黄霉素补糖工艺的试验

为了降低黄霉素生产成本,实现用补糖工艺替代补油工艺生产黄霉素,我们对黄霉素发酵补糖工艺中采用的3种不同补糖方式进行了试验.结果表明,采用根据总糖消耗量补糖法的效价比采用间歇补糖法、连续恒速补糖法的效价分别高24.2%和13.7%.采用根据总糖消耗量补糖法与黄霉素发酵传统补油工艺相比,平均效价相当,但是罐批生产成本却比其低35%.     

Effects of Natustat supplementation on performance, feed efficiency and intestinal lesion scores in broiler chickens challenged with Eimeria acervulina, Eimeria maxima and Eimeria tenella

The effects of dietary supplementation of Natustat™, a propriety plant derived product (Alltech Inc., KY, USA) and Salinomycin, on performance, feed efficiency and intestinal lesion scores were observed during two Eimeria challenge trials in broiler chickens. In the first trial chickens were challenged with Eimeria sp. via infecting the litter with a known amount of Eimeria oocysts. In the second trial the source of the Eimeria challenge was the litter from the first trial and the same treatment groups were assigned to the same pens as in the initial trial.

Birds were placed 55 per pen with seven pens per treatment. Performance parameters were recorded on days 21 and 42 during both trials. Intestinal lesion scores were assessed on days 14 and 21 during Trial 1 and on day 21 during Trial 2. Average weight gain and feed conversion ratios were significantly improved in the Natustat™ and Salinomycin treatment groups when compared to the non-supplemented infected group. Furthermore, lesion scores were lower on all sampling days in the Natustat™ and Salinomycin groups when compared to the non-supplemented group. However, only lesions associated with Eimeria tenella were significantly lowered by Natustat™ and Salinomycin supplementation.

Natustat™ and Salinomycin were equivalent in alleviating the negative performance effects associated with coccidiosis challenge. In summary, Natustat™ has the potential to be used as a natural alternative to chemotherapeutic drugs for Eimeria control.     

Effect of flavomycin on the apparent digestibility of crude nutrients in wethers, parameters of rumen fermentation in cattle and feed intake and weight gain of heifers

Three experiments with five wether each were carried out in order to investigate the influence of various levels of flavomycin (0, 5 and 10 mg per animal and day) on apparent digestibility of artificially dried grass. A short time individual feeding experiment (42 days) with 9 bulls and a long term individual feeding experiment (225 days) with 52 heifers were conducted. Animals consumed 0 or 30 mg flavomycin per day. Parameters of rumen fermentation were investigated. Feed intake and weight gain were measured in the experiment with heifers. Flavomycin did not significantly influence the apparent digestibility of organic matter and crude nutrients as well as parameters of rumen fermentation. Flavomycin did not influence dry matter intake, but increased significantly weight gain (49 g per animal and day, 10.5%) and reduced feed and energy required per kg weight gain (10.6%) in heifers. The reasons of ergotropic effects of flavomycin are mostly unknown at present.     

Comparative investigation of salinomycin and flavophospholipol in sheep fed different composed diets.

The effects of salinomycin and flavophospholipol, and their relationship with the diet, were studied in nine ruminally and duodenally cannulated wethers. Within the composition of the ration, the levels of rumen degradable protein (RDP) and non-structural carbohydrates (NSC) were changed (diet H: 74% RDP and 38% NSC; diet M: 57% RDP and 32% NSC; diet L: 48% RDP and 23% NSC). There was no clear treatment effect of flavophospholipol on propionate concentration. Salinomycin supplementation appeared to be more effective than flavophospholipol in the increase of propionate concentration at the expense of acetic acid. Salinomycin significantly reduced the ammonia concentration of the rumen fluid. Microbial N content of the duodenal digesta was significantly lower when salinomycin was used. Salinomycin inhibited proteolysis and reduced the efficiency of microbial protein synthesis. The effect of salinomycin on ruminal N metabolism was independent of the composition of substrate. Unlike salinomycin, flavophospholipol tended to increase proteolysis in the rumen and did not inhibit protein synthesis. The effect of salinomycin on ruminal fermentation and the duodenal flow of nutrients were independent of substrate composition.     

糖萜素对仔猪免疫功能的影响研究

本试验研究了饲料中添加糖萜素对早期断奶仔猪免疫机能的影响。采用完全随机试验设计将试验分为5组，第Ⅰ组为对照组；第Ⅱ、Ⅲ、Ⅳ、Ⅴ组分别添加250 mg/kg糖萜素、500 mg/kg糖萜素、250 mg/kg糖萜素+4 mg/kg黄霉素、4 mg/kg黄霉素。研究结果表明：糖萜素单独使用及与黄霉素合用均能提高仔猪血清中TP、GLO和G/A的值，以第Ⅲ组的效果最好；糖萜素单独使用及与黄霉素合用能显著提高血清IgA水平（P<0.05）,各试验组比对照组分别提高43.21%、104.89%、73.21%、27.74%；IgG各试验组比对照组分别提高10.50%、12.07%、11.05%、10.26%；血清中BUN各试验组比对照组分别增加2.67%、2.96%、2.81%、2.52%，但差异不显著（P>0.05）；血清中GLU各组间差异不显著（P>0.05）；血清中AST、ALT和ALP第Ⅲ组显著（P<0.05）高于其他组，而LDH活性各试验组与对照组相比分别下降2.71%、4.02%、2.96%、1.65%。