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<正> 与畜禽饲料相比,鱼类配合饵料的加工特点之一,是原料粉碎粒度要细,要求达到60目。而目前国内的饵料加工厂一般采用φ1.2mm筛孔的锤片式粉碎机或φ0.8mm爪式粉碎机,粉碎粒度只能达到20～30目左右。提高粉碎细度对耐水性和饵料系数 (?)切关系。粉碎细度提高,在一定工艺条件下可以压制出表面光滑、内部结构紧密的颗粒,可以延长水中浸泡渗透时间,减少散失量;同时也有利于鱼类的 相似文献
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试验研究了原料粉碎粒度、调质温度、后熟化时间、入模水分和环模压缩比五个因素对水产颗粒料耐水性的影响。结果表明:①通常鱼用饲料的粉碎粒度过40目(0.425mm)≥95%、调质温度控制在85℃以上、原料入模水分在14%～16%、后熟化时间为10～15min,环模压缩比在15左右为宜;②河蟹配合颗粒饲料的粉碎粒度过80目≥90%、调质温度控制在80～90℃、原料入模水分在17%～20%、后熟化时间在20～30min、环模压缩比在18～20为宜;③对虾配合颗粒饲料的粉碎粒度过80目≥90%、调质温度控制在80～90℃、原料入模水分在17%～20%、后熟化时间在20～30min、环模压缩比在18～22为宜。 相似文献
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鱼虾饲料同畜禽饲料除营养配方的设计、原料的选择不同外,对加工制粒更有其特殊要求,一般要求鱼饲料颗粒在水中耐水性≥0．5小时,虾饲料颗粒耐水性≥2小时,以减少散失,提高饲料利用率,这也是配合饲料的养殖实践所提出的要求,目前在南方大部分地区也成为养殖户衡量水产颗粒饲料是否合格的首要标准。也是任何一家企业要跨入水产饲料行业必须首先解决的问题。对于如何解决水产颗粒饲料的耐水性问题,一般采用两种方法：（一）增加淀粉含量较多的原料,如次粉、小麦粉。进行充分的前熟化和后熟化。使饲料原料中的淀粉糊化而产生一定粘结… 相似文献
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饲料系数又称增肉系数 ,是指鱼类摄食量与增重量的比值。水产饲料系数是鱼用配合饲料质量评定的依据之一。饲料系数与饲料质量、饲料利用率和投饲技术等因素密切相关。人们都期望使用较少的饲料 ,获得较高的鱼产量。一般可采取如下措施降低饲料系数。1 配合饲料质量应达到规定的产品质量标准1 1 饲料原料粉碎粒度要求通过 40目筛 ,60目筛上物不得超过 1 0 %。1 2 水中稳定性高。鱼用配合饲料中需加粘合剂或采用后熟化工艺 ,使配合饲料 (颗粒 )能在水中维持 3ｍｉｎ以上时间不溃散。1 3 颗粒长度与直径的比值以 2∶1适宜。不同鱼类的… 相似文献
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挤压膨化水产饲料的优点 总被引：3，自引：0，他引：3
1 挤压膨化工艺设计挤压膨化工艺流程见图1。 在挤压膨化之前,先对原料进行微粉碎,保证在混合物料中,不含有能堵塞挤压膨化机冲模的大颗粒存在,更主要的是使得物料在调质时,糊化更充分,颗粒成型时粘合性好,结构紧密,耐水性好。淡水鱼料要求全部通过20目分级筛,40目筛上物不大于30 %;河蟹、虾料要求全部过40目筛,80 %过60目筛;鳗、鳖料要求全部过60目筛,80目筛的通过率达95 %。根据需要,在挤压膨化和烘干后,还可用油脂、维生素、调味剂等对饲料颗粒表面进行包衣处理,方法可多样化。一般喷涂液是在旋转的圆桶内,通过喷雾或喷洒形式,对产品进行… 相似文献
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提高锤片式微粉碎机产量的几点探讨 总被引：1，自引：0，他引：1
近年来,随着饲料工业的逐步发展,水产饲料也越来越被广大饲料厂所看好。由于水产动物摄食量小,消化道短,消化能力差,通常要求水产饲料粉碎得相对畜禽料来说比较细。因为颗粒越细,其表面积越大,则水产动物的消化液与之接触面积就越大,从而提高了饲料的消化率,增加其营养报酬。因此,粉碎工段在整个生产工艺中占有极其重要的地位。据报道,通常鱼饲料在制粒之前应粉碎至几何平均粒度０．５ｍｍ或以下,如普通淡水鱼料,要求全通过２０目筛、４０目筛上物不大于３０%;河蟹、虾等饲料要求全通过４０目筛、８０%过６０目筛;鳗、鳖料要求全通过６０目… 相似文献
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水产饲料要求有一定的耐水性，即在一定的时间内，颗粒不溶化，营养成份不散失于水中，以免造成浪费和污染水质，利于水产动物摄入。在配方中加入通过调质后能产生粘性的物料如面粉，是水产饲料提高耐水性的主要方法，因而，面粉品质的好坏直接影响到耐水性的好坏。 面粉品质的评定： ① 感观 新鲜、有面粉香味，无异常气味。 ② 细度 100％通过 100目筛，无细屑以及麸皮。 ③ 筋度 湿筋度要求大于 30％，筋质好，面筋表面光滑，弹性好。有些面粉湿筋度 35％以上，但筋质不好，弹性差，面筋表面粗糙 ,用这样的面粉生产出的… 相似文献
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特种水产饲料的粉碎工艺和设备 总被引：4，自引：0，他引：4
水产动物消化道比较短,所以要求饲料粉碎得比较细,如一般鱼饲料要求全部通过20目分析筛,40目分析筛筛上物不大于30 %;中国对虾料0.425 mm编织筛(40目)筛上物不大于30 %,在0.250 mm编织筛(60目)筛上物不大于20 %;白仔鳗饲料98 %通过100目筛,黑仔鳗饲料98 %通过80目筛,成鳗料98 %通过60目筛;稚鳖和幼鳖料100目筛筛上物不大于5 %,成鳖料和亲鳖料80目筛筛上物小于5 %;河蟹料粒度要求与对虾料相似。河蟹、虾料在水中保形要求在3 h以上,鱼料耐水性要求30 min以上。饲料粉碎得细一点,表面积增大,有利于调质和颗粒成形,使颗粒有良好的水中稳定性,可… 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
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。 相似文献
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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。 相似文献
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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。 相似文献
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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. 相似文献
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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. 相似文献