饲用抗生素作为生长促进剂被广泛应用于畜牧业生产,到目前为止已有60多种抗生素被用作饲料添加剂,饲用抗生素在提高动物生产性能具有很重要的作用,但与此同时,正威胁着人类健康以及造成环境污染,加之动物饲养者违规添加或不合理使用抗生素等现象不断发生,全球每年消耗的90％抗生素总量用在了食用动物,食品安全事件、耐药菌、超级细菌不时见诸报端.

随着现代畜牧业的发展,规模化、标准化、机械化、信息化生产模式的建立,基层畜禽养殖场在硬件方面的投入不断加大,各项生产技术操作规程、日常生产生活管理制度日臻完善,但是在日常生产管理过程中,一些种畜禽养殖场、孵化场及商品畜禽养殖场因粗放散漫的生产经营管理习惯,并未使各项生产管理制度、生产技术操作规程得以严格贯彻落实,先进的硬件设施亦未充分发挥作用,制约着养殖场产量的提高和产品质量的提升,养殖效益难以持续向好,给企业长期稳定生产带来困扰,亟须解决.

在基层畜禽养殖管理过程中,在贯彻落实各项生产技术操作规程、日常生产生活管理制度及先进硬件设施的充分应用方面还存在很多的问题.主要从畜禽品种引进、消毒设施配置和应用、养殖器具清洗消毒、饲料储存和饲喂、养殖档案记录和保存等几方面入手,分析存在的问题和不足,并提出改进对策,以期对今后基层畜牧养殖管理提供科学合理的指导,充分发挥畜牧业发展潜力.

盐酸左旋氧氟沙星是第3代喹诺酮类药物氧氟沙星的左旋体,抗菌活性高.5龄第2天健康及感染黑胸败血芽孢杆菌(Bacillus bombysepticus,Bb)家蚕幼虫用500 μg/mL盐酸左旋氧氟沙星药液浸渍的桑叶添食处理后,采用超高效液相色谱测定健康家蚕和感病家蚕血淋巴中的药物浓度,用DAS 2.0处理软件分析得到药物动力学参数,为生产上合理使用该药物防治家蚕细菌病提供科学依据.结果 表明健康家蚕和感染Bb的家蚕添食盐酸左旋氧氟沙星后的血药经时过程均符合一级吸收一室开放式模型,健康家蚕的药动学参数吸收速率常数(Ka)为(0.507±0.032) h-1,吸收半衰期(T1/2K)为(1.425±0.017)h,最高血药浓度(Cmax)为(5.352±0.155) μg/mL,说明蚕体对盐酸左旋氧氟沙星吸收良好,血药浓度高;与健康家蚕相比,感染Bb家蚕的Ka由0.507 h-1降至0.386 h-1,T1/2Ka由1.425 h延长至1.798 h,药-时曲线下面积(AUC)从38.770μg/(mL·h)降为35.909 μg/(mL·h),分布半衰期(T11/2α)由1.679 h缩短为1.483 h,消除半衰期(T1/2β)由4.922 h降为2.450 h,说明Bb感染家蚕后导致药物在蚕体内的吸收减慢,吸收能力下降,代谢和消除加快.建议生产上用盐酸左旋氧氟沙星防治Bb感染引发的家蚕细菌病时,可适当提高药物剂量和增加给药次数,使蚕体内药物浓度维持在较高水平,保证良好的防治效果.

当前,国家及社会方方面面对环境保护生态安全问题日益重视,粗放的生产生活方式面临着前所未有的挑战.特别是当前畜牧业的发展,在为人民提供了丰富多样的畜产品的同时,畜禽粪污等废弃物由于处理或利用不当而带来的生态环保问题日益凸显.虽然无论是在畜禽废弃物处理利用设施还是技术服务方面,我们都投入了很多的人力、物力和财力,也取得了不小成效.但总体来看,还面临着管理粗放,各种技术不能很好运用等一系列问题,在此仅从农村畜禽粪污处理方面存在的问题及对策谈一下自己的思考.

To provide a scientific basis for clinical application, the pharmacokinetics characteristics of oral administration at a dose of 18 mg/kg Norfloxacin·HCl were investigated in healthy and Bacillus bombysepticus infected silkworm. Concentrations of Norfloxacin·HCl were determined by the High Performance Liquid Chromatography (HPLC) and data were analyzed with the pharmacokinetic computer program MCP-KP. The results showed that blood concentration-time curves in healthy and infected silkworm all could be described by one-compartment open model with the first order absorption. Compared with healthy silkworm, the pharmacokinetic parameters of Norfloxacin HCl in infected silkworm were different, such as area under concentration-time curve (AUC) decreased from 81.194 mg/(h·L)to 66.105 mg/(h·L), the absorption half time (T1/2Ka) increased from 1.252 h to 1.591 h, the distribution half time (T1/2α) decreased from 2.673 h to 1.981 h, and the elimination half time (T1/2β) decreased from 9.298 h to 5.338 h. The obtained results indicated the infection could decrease the competence of absorption and the rate of absorption, while increase the distribution time and elimination time.

One hundred and fourteen strains of endophytic fungi were isolated from the roots,stems and leaves of different mulberry varieties using the tissue culture method.Through the morphological identification,they belonged to 21 genera,including Fusarium,Alternaria,Scytalidium etc.The result showed endophytic fungi in mulberry exhibited the broad biodiversity.The distribution of endophyte was different among mulberry varieties.The type and quantity of endophytic fungi had great difference among different organs of the same variety:rootsstemsleaves.Fusarium was the dominant population in roots,while Alternaria was the dominant population in stems and leaves.Monilia and Fusarium were isolated from three organs,and the others were isolated from one or two organs.

Antibacterial effects of eleven kinds of Chinese herbal medicine in vitro were investigated to some pathogenic bacteria popular in sericulture production.Results showed that there were different degree bacteriostotic actions to Bacillus bombysepticus,Bacillus thuringiensis and Bacillus prodigicsus with any of skullcap,coptis,corktree bark,rhubarb,ash bark and forsythia fruit.But there were no bacteriostatic actions to three bacteria with honeysuckle flower,dandelion,cocklebur fruit and milkvetch.With dilution method of medicine solution in petri dish,the minimal inhibitory concentrations(MIC) of four species of Chinese mono-herbal medicine,nine combinations of each two species of medicine against three bacteria were determined.The results indicated that the MIC of two kinds of Chinese herbal medicine were 31.25～125 mg/mL and 7.8125～62.5 mg/mL.It was showed that the compound formula preparations had advantage in pharmacological activity.

合作制种是20世纪80年代末90年代初随着桑蚕生产的不断发展,用种量的大量增加而兴起的.它是家蚕制种单位与养蚕户之间的一种合作共赢关系,一般由村委会作中介,签订<意向合作书>、<原蚕制种及收购合同>,由家蚕制种单位提供原种和桑园管理与原蚕饲育技术指导,养蚕户利用自己的桑园、蚕房、设备和工具来饲养原蚕,制种单位负责收茧,就地制种或回制种单位制种的一种新型合同制种方式.合作制种一般以春季为主,秋季作为补充.自推行以来取得了良好的经济效益和社会效益.本人将多年来的合作制种工作进行总结,并提出相应的工作规范,对合作制种点特别是新增制种点的工作开展提供参考.

20世纪70年代以来,国内外在蚕用消毒药物方面进行了大量的筛选研究工作,按spaulding对化学消毒剂分类的观点,常用的蚕用消毒剂可分为氯制剂、醛制剂和表面活性剂三类,使用最多的当数氯制剂、醛制剂两类.