通过营养调控缓解畜禽生产对环境的污染

针对畜禽生产规模不断扩大和集约化程度不断提高，畜禽生产对环境的污染日益严重的实际情况，本文从（1）饲料原料的选择；（2）减少畜禽粪便中氮的排出量；（3）降低畜禽排泄物中磷的排出量；（4）减少重金属的污染；（5）利用饲料添加剂；（6）改进饲料加工工艺6个方面系统综述了通过营养调控缓解畜禽生产对环境污染的具体措施。     

饲粮配制与环境保护

饲料营养学家不仅要根据饲料价格，畜禽性能，而且还要根据畜禽粪便中各种养分浓度来制定日粮营养水平。在当前公众对环境保护有迫切要求时，促使饲料工业要有保护环境的意识。养猪生产中潜在的污染物是饲料中的各种养分。在美国，最关心的养分是氮。因它有可能通过土壤转移而污染水，人们担心饮水中硝酸盐过多。采取各种对策有可能大大减少猪粪中排出的N。如有效地提高饲料利用率，就可减少N的排出量，饲料需要率可减少0.25个单位，N排出量可减少5──10％。20年来，从25公斤到100公斤的高产猪群，饲料需要率已从4.0下降到2.85，控制营养…     

合理调制饲料降低畜禽粪便中氮、磷、铜排出量

调整饲料可降低畜禽粪便中营养物质氮、磷、铜的排出量。利用工业氨基酸可使粪氮的排出量降低10%～12%,而植酸酶的使用可使粪磷的排出量降低约30%,60mg/kg纳米铜对仔猪的促生长效果等同于240mg/kg硫到铜,从而减少粪便中铜的排出量,减轻了对环境的污染。     

合理调制饲料,降低家禽粪便对环境的污染

畜禽养殖的集约化生产给人类提供了丰富的畜产品,养殖者也得到了可观的经济效益,但动物产生的粪便已成为环保大敌。科学证明,动物日粮的植物性饲料中有2/3的磷不能被动物利用,造成磷资源浪费,引起严重的环境污染。饲料中蛋白质的利用率仅30%～50%,大部分的氮随着粪尿排出体外,增加了水和大气污染程度。因此,有效的营养措施、科学的日粮配制技术和生物技术应用于饲料中,可从根本上减少畜牧生产对环境造成的污染。在防止家禽排出物引起的公害及污染方面,饲料残留物引起的公害已被重视。通过调整饲料可降低家禽粪便中营养物质的排出量。利用工业氨基酸可使粪氮的排出量降低10%～12%,而植酸酶的使用可使粪磷的排出量降低约30%。     

“精准营养技术”用于生猪养殖须注意的问题

"精准营养技术"用于养猪生产可以获取良好的收益,在促进猪生产性能正常发挥、提高养殖生产水平、节约养殖成本、减少饲料资源浪费、降低猪粪便中的氮磷排出量从而减轻对环境的污染程度、保障畜禽产品食品质量安全、有益人类健康等方面起到重要的作用。但是,"精准营养技术"在养猪生产应用中还存在诸多问题,应引起养猪界及饲料界同仁的高度重视并加以解决。     

降低养殖业中氮污染的措施

氮是畜禽粪便中造成环境污染的主要物质.降低养殖业中氮污染的措施是减少畜禽粪便中氮的排出量和加强畜禽粪便的处理利用,本文对此进行了综述.     

环保型饲料添加剂研制成功

中国农科院的科学家日前研制出饲料用基因工程酵母。中国农科院饲料研究所和生物技术研究中心，从１９９６年开始合作进行利用生物反应器大规模、低成本的生产饲料添加剂植酸酶的研究，从黑曲酶中克隆了适合在饲料中使用的植酸酶基因。我国饲料资源缺乏，饲料添加剂品种少，该项研究成果可用来大规模廉价生产新型饲料添加剂———植酸酶。植酸酶是一种能将饲料中的植酸水解成无机磷和肌醇的新型动物饲料添加剂。这种饲料添加剂可提高动物对磷的利用率，使畜禽粪便中磷的排出量减少４０％～７５％，能减轻江河等环境的磷污染，减少饲料用磷消…     

环保型饲料添加剂—植酸酶研制成功

中国农科院的科学家日前研制出饲料用基因工程酵母。中国农科院饲料研究所和生物技术研究中心 ,从 1996年开始合作进行利用生物反应器大规模、低成本生产饲料添加剂植酸酶的研究、从黑曲酶中克隆了适合在饲料中使用的植酸酶基因。我国饲料资源缺乏 ,饲料添加剂品种少 ,该项研究成果可用来大规模廉价生产新型饲料添加剂———植酸酶。植酸酶是一种能将饲料中植酸水解成无机磷和肌醇的新型单胃动物饲料添加剂。这种饲料添加剂可提高动物对磷的利用率 ,使畜禽粪便中磷的排出量减少 40 %～ 75 % ,能减轻江河等环境的磷污染 ,减少饲料用磷消耗。…     

透析环保生态型蛋鸡饲料

1 环保生态饲料的基本要求 一般认为,环保生态型饲料应具备以下条件:无臭味、无污染、消化吸收好,饲料利用率高;畜禽生产性能和繁殖性能好,疾病少,氮、磷及重金属元素排放少;畜产品安全、卫生、优质.利用现代蛋鸡营养原理,通过科学的饲料配制技术可以减少蛋鸡粪便的排出量,降低排泄物中蛋白质、脂肪等的残留,减少腐败分解产生的恶臭...     

营养调控治理畜禽养殖的氮污染

正氮是畜禽粪便中造成环境污染的主要物质,是一个对环境不可忽视的危害因子。降低养殖业中氮污染的措施是减少畜禽粪便中氮的排出量和加强畜禽粪便的处理利用。本文基于营养调控角度对畜禽养殖氮污染进行简要分析,以探讨减少氮污染,促进畜牧业的可持续发展。     

癸氧喹酯干混悬剂含量测定的改进

采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。     

商会自治的基石——商会自治规范研究

在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。     

猪毛色遗传的研究进展

本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。     

中华人民共和国农业部公告 第267号

为贯彻落实《兽药生产质量管理规范》(简称《兽药GMP》),进一步推动兽药GMP实施进程,我部制定了《兽药生产质量管理规范检查验收办法》,现予公告。本公告自2003年6月1日起施行。附件:兽药生产质量管理规范检查验收办法二○○三年四月十日第一章 总则 第一条 为推动《兽药生产质量管理规范》(以下简称兽药GMP)的实施,规范兽药GMP检查验收工作,制定本办法。 第二条 农业部负责全国兽药GMP管理和检查验收工作;负责制修订兽药GMP检查验收管理规定;负责兽药GMP检查员队伍建设和监督管理工作,负责国际兽药贸易中GMP互认工作。 …     

鸡败血支原体垂直传播模式及其阻断方法

以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。     

Comparison of 2 methods of centesis of the bursa of the biceps brachii tendon of horses

REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air.     

不同样本商品蜂蜜中硒含量的测定

用硝酸和高氯酸消化蜂蜜,使硒游离出来,在微酸性环境下,硒和2,3-二氨基萘(DAN)生成有较强荧光的物质,用环己烷萃取,在激发波长378nm,荧光波长518nm处测定其荧光强度。蜂蜜中硒含量范围:0.10～0.82μg/g。表明:蜂蜜应视为天然富硒营养品。     

乳酸杆菌益生作用机制的研究进展

乳酸杆菌作为益生菌广泛用于人和动物。本文综述了乳酸杆菌改善宿主健康的机制。乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道。文章重点讨论了乳酸杆菌表面成分（表面蛋白、脂磷壁酸和肽聚糖）与肠道受体（Ｃ型凝集素受体、Ｔｏｌｌ样受体和 Ｎｏｄ样受体）,阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制。     

Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF

Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo.