浅析影响饲料颗粒的耐久性指数和粉化率的因素及其提高方法

当中国饲料工业发展近２０年来，用户对颗粒饲料的各项指标要求越来越高，不但要求内在质量要好（如：营养性能、防病、卫生环保等内容），而且要求外在质量亦越来越高（如：颗粒的色、香、味，大小长度比例、耐久性指数（PDI）、粉化率、水中散失率等）。例如：鸭、鸽、鹅料和水产料等对颗粒的耐久性指数和粉化率、水中散失率等要求较高，引起了各饲料厂的重视和研究，并变成质量保证的重要指标。本文主要浅析影响饲料颗粒的耐久性指数和粉化率的因素及探讨提高这两个方面质量的方法，以及一些注意事项。１影响饲料颗粒的耐久性指数犤PD…     

影响制粒生产线工效因素初探

影响制粒生产线工效因素初探四川省什邡县饲料公司张济舟在颗粒饲料生产中，影响制粒生产线正常运转的因素多种多样，本文拟就此略述己见，愿与同行商榷。１．制粒生产线设备本身因素１．１压模材质、模辊间隙压模材质用铬镍合金钢经精密加工处理，表面硬度＞ＨＲＣ５７。...     

颗粒饲料机械设备的选择、使用和维护

颗粒饲料是将混合后的全价配合饲料，经制粒机的压轴和压模的挤压，通过模孔成型，而后经过冷却、碎粒、分级、喷涂等工序加工而成。颗粒饲料生产在西方发达国家已有50多年的历史，近二十多年来，颗粒饲料在许多国家都有比较大的发展，在关、日、德等国家，颗粒饲料约占饲料总量的70％以上。颗粒饲料在我国是从20世纪70年代末发展起来的，近十几年迅速发展，特别是肉鸡、鱼虾和观赏动物颗粒饲料日益普及。颗粒饲料虽然加工成本高，但饲养效果明显优于粉状饲料，具有明显的经济效益。     

浅议调质工艺影响饲料质量的几个因素

浅议调质工艺影响饲料质量的几个因素广州市饲料研究所李小林大部分厂，特别是中小型饲料厂，一定程度上都存在颗粒饲料产量偏低，出机含粉率偏高，硬度低等缺陷，无形中提高了颗粒料的制作成本，降低了饲料的质量，从而影响了企业的效益和声誉。造成这一结果的最主要的因...     

国外饲料颗粒耐久性测试器及其比较

颗粒饲料的工艺质量由多种因素构成，但最重要的则是颗粒耐久性。破碎的颗粒料会使畜禽的采食量和饲料转换率下降，产生粉尘，饲料的无形损耗增大，而最坏的影响莫过于顾客的抱怨。颗粒耐久性测试对于饲料厂至关重要，却又常常被厂家忽视，因为人们的注意力往往是放在资金...     

获得最佳制粒质量的途径

饲料客户往往用长度、颜色、质是、密度、持久性、气味、水分和粉化率来衡量制粒的质量。然而，衡量制粒质量的最常用指标是持久性、通常用颗粒持久性指数（PDI，Pellet Durability Index）来表示（Sheideler1991）。从图1中可以看出，配方、粉碎粒度、调质、模孔规格均可以影响颗粒料的持久性（Turner1995），春中原料选择和粉碎粒度是决定颗粒料持久性的主要因素（Stark1994），因此，饲料生产者不应单靠制粒工艺的调节来改善颗粒料的质量，而应按各因素对颗粒质量影响程度的不同分别加以考虑。     

冷水制粒

<正> 颗粒饲料生产过程要用蒸汽,在南方缺煤地区由于煤价较贵而使加工费用增大。为了降低生产成本,从八三年六月起,龙海县饲料厂就开始利用0.8～2.4吨/时的卧式压粒机试验研究冷水制粒工艺。试验说明,冷水制粒成品质量的优劣,关键在于粉料的冷水混合工序,它直接影响颗粒饲料的密度。与水混合后的粉料含水量过大,颗粒软,压出物起毛,易断碎,无光泽,亦无饲料香味;同时,浆物粘于压辊易堵塞压模孔。电流可高达120安培,压粒系统温度骤增到     

冷却设备的选用及影响颗粒料水分的因素

在饲料厂的颗粒工段生产过程中，颗粒饲料冷却后含水率必须符合安全贮存的要求。如何有效地控制颗粒饲料的含水率。本文就冷却工序选用设备和排除影响颗粒料水分主要因素阐述如下。1冷却设备的选择及冷却风网设计注意事项　　在制粒过程中，因为必须被通入高温蒸汽对物料进行调质，同时物料通过压模被强烈挤压，使颗粒出模温度达85℃左右，水分达15％左右。在这种情况下颗粒容易破碎，贮存容易发生霉变。因此必须对制粒后的高温高湿颗粒通过冷却处理，进行湿热传递，及时扩散蒸汽添加的表面水和热量，使颗粒料冷却到比室温高5℃以下，水分降…     

改进工艺优化颗粒饲料品质的途径

<正>颗粒饲料以其营养均衡、适口性好、易包装运输等优点,深受广大养殖户喜爱。制粒机制粒快、效果好,设计特殊孔的滤网,其摩擦滤网杆能扎碎筛滤坚固粒子,是现代化饲料生产线必须具备的制粒设备。在制粒机生产颗粒料时,如果由于颗粒料的调质原因而出现产品外观、形态不正常的颗粒料,会影响产品质量和效益,因此可以通过改进颗粒饲     

压粒机轧辊打滑的控制

某些特定的饲料配方或生产条件会引起压粒机轧辊打滑。轧辊打滑降低了生产效率，如不及时处理，最终将导致压粒机模孔堵塞。生产实践表明，无论采用什么方法，只要饲料的性状发生变化，或加工过程中其它条件发生变化，轧辊打滑的现象就有可能发生。压粒机前的各种处理设备有时会表现出某些可能将导致打滑或模孔堵塞的迹象。例如，压粒机的主安培表、螺旋喂料器、喂料槽中的探针及压模前的分流阀等。一旦当这些仪器表现出异常情况时，模孔已充满了糊状饲料，这时轧辊打滑或模孔堵塞将在所难免。压粒机轧辊的转速是颗粒饲料生产中最为关键的因…     

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。     

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。     

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。     

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。     

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。     

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.