畜禽安全用药的注意事项

畜禽用药安全与否关系到畜禽的生命安全、畜禽生产力的高低、畜禽产品质量的优劣和环境保护,是畜禽用药时必须注意的,有时是首要的。笔者就畜禽安全用药的一些注意事项陈述如下。     

畜禽标识制度化是防疫工作的基础

畜禽标识制度化是畜禽免疫注射的同时,佩带畜禽标识、编标识号码,出免疫证,建立养殖档案.加强流通环节的监督,对畜禽及畜禽产品可进行追溯,规范畜禽防疫工作,生产安全无公害的畜禽及其产品.     

我国畜禽种业发展取得成效、面临瓶颈及相关建议

畜禽种业是稳定畜牧业生产和保障畜产品供给的关键；畜禽种源关系到国家安全战略，为了夯实我国畜禽养殖业的发展基础，必须实现种业科技自立自强、种源自主可控。近年来，我国持续实施畜禽遗传改良计划，建成畜禽育种体系及畜禽种业企业阵型，畜禽种业得到长足发展，自主育种取得显著成效，已成功培育多个优良畜禽品种，为确保肉蛋奶等有效供给提供了种业支撑。但到目前为止，实现畜禽种业振兴仍面临着种质资源保护利用不够、部分优良畜禽核心种源依赖进口、种畜禽企业综合实力偏弱等诸多难题，畜禽养殖业的长期发展也面临着巨大的压力和挑战。因此，建议种畜禽企业充分把握良好发展机遇，加快国家畜禽种质资源库建设，加强畜禽生物育种基础研究和技术创新研究，加快建设和布局畜禽种业创新基地，加强畜禽重大新品种培育，加强科企融合推动畜禽育种产业化，尽快推动和实现畜禽种业振兴。     

浅析畜禽标识的规范建立和管理工作

畜禽标识是国家农业部批准使用的耳标、电子标签、脚环以及其他承载畜禽信息的标识物,在我国从事畜禽及畜禽产品生产、经营、运输的活动,必须遵守。《畜禽标识和养殖档案管理办法》要求畜牧业生产经营行为,加强畜禽标识的建立和管理,建立畜禽及畜禽产品可追溯制度,有效防控重大动物疫病,保障畜禽产品质量安全。     

依法加强畜禽养殖管理促进现代畜牧业可持续发展

畜禽养殖管理是对畜禽养殖区域的规划布局、畜禽养殖场的设置、畜禽的饲养、畜禽疫病和养殖污染的防治等及其相关的监督管理活动以法律的形式进行约束,旨在规范畜禽养殖行为,防止畜禽疫病和有毒有害物质残留对人体的危害,防治畜禽养殖污染,保护人体健康,促进畜牧业可持续发展.     

关于农村兽医在畜禽疾病防治中的误区对策探讨

在我国农村,畜禽养殖业占有很大的比重,大部分畜禽养殖业以农户为单位,养殖规模大小不一。但是,由于畜禽养殖户在养殖畜禽过程中,缺少相应的防治意识,导致畜禽疾病防治过程中存在误区,给畜禽健康带来影响。文章主要从农村兽医在畜禽疾病防治中的误区,并提出相应的防治对策,希望能为畜禽养殖户养殖畜禽提供参考。     

畜禽安全用药的注意事项

畜禽用药安全与否关系到畜禽的生命安全、畜禽生产力的高低、畜禽产品质量的优劣和环境保护,是畜禽用药时必须注意的,有时是首要的。笔者就畜禽安全用药的一些注意事项陈述如下。     

畜禽养殖场饲养工的聘用和培养

畜禽养殖场是畜禽的养殖之地，畜禽养殖场的饲养工是直接与畜禽接触的一线人员，畜禽饮食的供应、粪便等排泄物的清除、畜禽健康状况的观察均由饲养工来完成。     

畜禽养殖污染治理现状及解决措施

通过分析指出了广汉市畜禽养殖污染的原因,提出了加强畜禽养殖污染治理、科学规划畜禽养殖场、做好畜禽养殖污染治理宣传工作、发展生态型畜禽养殖业以及做好畜禽粪便的综合利用等解决措施。     

畜禽及畜禽产品的溯源体系构建

畜禽及畜禽产品质量安全已成为人类赖以生存和健康发展的重大公共卫生安全问题.如何实现畜禽产品从养殖到餐桌的全程质量监控已成为当前的一个重大课题.针对畜禽产品质量安全存在的问题与成因的分析,让畜禽产品生产和流通过程变得可监督.在比较发达国家畜禽和畜禽产品可追溯系统和立法强制实施的基础上,研究制定适合中国国情的畜禽和畜禽产品可追溯系统的技术标准构架,构建一种适合国情的畜禽产品安全生产溯源系统.     

畜禽保种理论与方法研究进展

本文综述了畜禽保种理论和方法的研究进展,同时就分子标记辅助保种的一些情况进行了叙述。提出我国现阶段和今后在畜禽资源保护方面应采用以群体遗传学为基础的保种方法与以分子遗传学为基础的分子遗传标记辅助保种法相结合的方法。     

多梯度氮磷添加对高寒草甸植物群落生物量与氮磷含量的影响

为研究不同梯度氮、磷单独及混合添加对高寒草甸植物群落生物量、植物养分含量及化学计量比的影响,本实验分析了青海省门源县典型高寒草甸植物群落地上总生物量,功能群水平地上生物量,植物全氮、全磷含量及氮磷比对多梯度氮、磷添加的响应情况。结果表明：氮、磷添加均对群落地上生物量影响极显著(P<0.001);氮添加对禾草类和豆科生物量影响极显著(P<0.001);磷添加对禾草类和莎草类生物量影响极显著(P<0.001);氮磷交互作用对豆科和莎草类生物量影响显著(P<0.05)。群落水平上,氮添加显著提高了植物全氮含量,对植物氮磷比(N∶P)有正效应,磷添加显著提高了植物全磷含量,对植物N∶P有负效应,植物全磷对N∶P的负效应大于全氮对N∶P的正效应。本研究表明氮、磷添加可能会使高寒草甸植物群落组成和植物养分含量发生改变,植物群落逐渐向禾草类发展;此外,高寒草甸植物生长趋向于受氮磷共同限制。     

养羊业的引种和种性资源保护与利用

本文概述了20世纪后半叶中国养羊业引种和育种情况,归纳出中国养羊业发展的八项特点,从遗传学基本理论出发,简述了引种保种和生态适应性相互关联的问题,提出了当前养羊业发展过程中存在的值得思考的几个问题和商榷性建议。     

产甲烷菌的分离纯化培养及其培养基对于菌株的选择作用

产甲烷菌是一类能够将无机或有机化合物经过厌氧发酵转化成甲烷和二氧化碳的严格厌氧古细菌,其参与的产甲烷作用通常发生在厌氧发酵过程的最后一步。发酵产物甲烷则是目前加剧全球气候变暖的一种重要温室气体。为了进一步了解不同种类产甲烷菌的生物学特性,近10年来对于产甲烷菌分离培养技术的研究不断深入并受重点关注。作者介绍了产甲烷菌的典型生境与生物学地位、产甲烷菌的分类及生理特征,并着重阐述了产甲烷菌分离纯化培养技术及培养基中不同底物与化学抑制剂对于产甲烷菌的选择作用。     

基于校企合作的“湖北粮油班”畜牧兽医专业课程体系改革与实践

为了适应畜牧兽医专业订单式人才培养模式改革,突出职业教育的特点,提高毕业生的就业质量,对畜牧兽医专业课程整合化、模块化、最优化,融专业知识、职业应岗技能和职业综合能力培养为一体,改革和开发专业课程的教学内容,突出了职业教育的针对性、实用性和实效性等优点进行了概述。     

Influence of sarcoptic mange and cold and ambient temperature on blastogenic responses of lymphocytes and serum cortisol concentrations of pigs

Blood samples from sarcoptic mite-infested pigs were evaluated for effects of mite infestation and cold and ambient temperatures on lymphocyte blastogenic responses and for effects of mite infestation on serum cortisol concentrations. In experiment 1, sarcoptic mite-infested and noninfested pigs were housed in cold (5 to 15 C fluctuating) and thermoneural (25 C) environmental chambers for 5 weeks. Differences were not observed (P greater than 0.10) in blastogenic responses to phytohemagglutin or pokeweed mitogen between lymphocytes from infested and noninfested pigs on postinfestation days (PID) 7, 21, 28, and 35 in either environmental chamber. When lymphocytes from noninfested pigs were cultured with sera from infested pigs, alterations of blastogenic responses were not detected. Cortisol values were higher (P less than 0.05) in sera from sarcoptic mite-infested pigs, compared with those from noninfested pigs, at 4 PM on PID 14 and 4 AM and 10 AM on PID 15. Cortisol values were higher (P less than 0.05) in sera obtained at 10 AM on PID 14 and at 10 AM on PID 15 from pigs housed in cold chambers, compared with those from pigs housed in thermoneutral chambers. Interactive effects between sarcoptic mite infestation and cold ambient temperatures were not observed. At 4 AM on PID 15 (experiment 2), cortisol values were higher (P less than 0.05) in sera of infested pigs, compared with those in noninfested pigs. Seemingly, sarcoptic mange in pigs did not alter mitogen-induced lymphocyte blastogenic responses, but did increase serum cortisol concentrations, indicating that sarcoptic mange may be a stressor in pigs.     

Effects of farrowing crate floors on health and performance of piglets and sows

Three types of raised perforated floor were compared with floor-level concrete which had perforated flooring at the rear. Piglets on raised perforated floors grew faster (P less than 0.05) to 21 days than pigs on mainly solid floors (205 g/day and 198 g/day, respectively). The mortality in the first 21 days of all pigs born did not differ between raised (18.4 per cent) and mainly solid floors (18.7 per cent) and there were no effects of individual floor types on overall survival or on deaths due to crushing. The incidence of diarrhoea was not significantly less on raised than on solid floors (27 per cent and 34 per cent of litters, respectively) but antibiotic treatment time was shortened (0.9 days and 1.2 days, P less than 0.05). The incidence of splayleg was highest on fibreglass slats. Concrete floors caused most knee abrasions but the incidence of arthritis was unaffected. Approximately twice as many sows on mainly solid floors went off their feed or had a high rectal temperature compared with sows on raised perforated floors. No differences were observed between narrow or A-frame farrowing crates.     

Shape and size of teeth of dogs and cats-relevance to studies of plaque and calculus accumulation

Crown width, height and buccal surface areas were measured on heads or skulls of four dogs and four cats, and were compared with similar measurements on models of human dentition. Buccal surface area variability was greater in dogs and cats than in humans, and teeth of cats were smaller. Horizontal (gingival and occlusal halves) and vertical (mesial, middle, and distal thirds) buccal surface area variability was also greater in canine and feline teeth compared with human teeth. This increased variability suggests the need for testing of reliability and repeatability of scoring when using plaque and calculus indices based on horizontal or vertical segmentation. Buccal surface area variability between teeth also prompts questioning the validity of equal weighting of smaller, irregularly-shaped teeth when calculating a mean mouth score. Whether equal or more reliable results would be obtained from scores of whole teeth in comparison with segmentation indices used currently has yet to be determined.     

Colistin and tylosin enhances disaccharidase activities,and improves morphology and permeability of the intestine of broilers

ABSTRACT

1. The present study focused on the potential effects of antibiotics on intestinal digestion and integrity in broilers in terms of disaccharidase activity, electrophysiological properties and morphology.

2. One-day-old Arbour Acres birds were randomly allocated to one of four treatment groups for 42 days; control, colistin (20 mg/kg), tylosin (55 mg/kg) or chlortetracycline (CTC, 55 mg/kg) groups. Colistin and tylosin supplementation, but not CTC supplementation, caused an increase in body weight gain.

3. Colistin and tylosin elevated the activities of maltase and sucrase in the mucosa of the jejunum on d 42. Age caused a gradual decrease in the short-circuit current (Isc) and conductance (Gt) of the ileum, as a measure of permeability. The Isc and Gt of the ileum were higher in the colistin-supplemented broilers than in the control birds on d 42. Tylosin- and CTC-supplemented birds displayed Isc and Gt values similar to those of the control birds.

4. Colistin supplementation increased the villus area in the jejunum and thinned the muscularis mucosae in the ileum compared with the control group. Tylosin supplementation decreased the thickness of the muscularis mucosae and the depth of crypt in the jejunum. CTC thickened the muscularis mucosae in the jejunum and ileum.

5. Colistin and tylosin exhibited a beneficial effect on intestinal digestion and integrity by enhancing disaccharidase activities and improving gut morphology and permeability.     

鬼针草与含羞草化感作用及其入侵性的研究

采用培养皿滤纸法研究入侵植物鬼针草与含羞草根、茎、叶浸提液对种子萌发和幼苗生长的影响,从化感角度揭示外来植物的入侵机制。结果表明:1)鬼针草根、茎、叶浸提液随浓度升高显著抑制鬼针草和含羞草种子萌发,高浓度(0.04 g·mL^-1)的叶浸提液使萌发率降低了67%~87%;高浓度(0.04 g·mL^-1)的含羞草叶浸提液使其种子萌发率降低了21.7%,但对鬼针草种子萌发影响较小。2)鬼针草和含羞草根长随2种植物根、茎、叶浸提液浓度的升高而降低,尤其是高浓度的叶浸提液有较强抑制效应。3)各浓度的鬼针草根、茎、叶浸提液均能降低含羞草茎长,高浓度的叶浸提液抑制效应最强;高浓度(0.04 g·mL^-1)的含羞草茎和叶浸提液抑制鬼针草茎长,中等浓度(0.02~0.03 g·mL^-1)的根和叶浸提液促进鬼针草茎长;含羞草各器官浸提液对其茎长的抑制作用随浓度增大略有增强。4)鬼针草各器官浸提液(尤其叶浸提液)抑制自身根冠比,促进含羞草根冠比;含羞草各器官浸提液轻微降低自身根冠比,显著降低鬼针草根冠比。5)鬼针草对自身种子萌发率、根长及根冠比的化感强度大于鬼针草他感强度;鬼针草对含羞草茎长的化感强度大于其自感强度,也大于含羞草他感强度;含羞草对鬼针草根长及根冠比的化感强度大于其自感强度,也大于鬼针草他感强度。鬼针草主要通过抑制含羞草茎长,增强入侵性,而含羞草主要通过抑制鬼针草根的生长,增大竞争力。