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商品肉兔杂交组合及生产配套技术的研究 总被引：1，自引：0，他引：1
经新西兰白兔、加利福尼亚兔和哈白兔３个品种肉兔的杂交组合试验得出，加（♂）×新（♀），新（♂）×哈（♀）和哈（♂）×加（♀）是生产商品肉兔较好的杂交组合。生产的商品肉兔，４０日龄断奶重９９９．７５ｇ，９０日龄体重为２．５４ｋｇ，断奶至９０日龄的日增重为３０．８ｇ，料重比（含青干草）３．４６：１，屠宰率为５３．０５％。同时，探索了一套适合农户饲养商品肉兔的生产模式，即杂交组合＋青粗精料搭配＋早期生长优势＋综合防疫体系＋产品销售与加工增值。按此模式生产商品肉兔，可以获得满意效果。 相似文献
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利用波尔山羊与关中奶山羊进行级进杂交。分别对波奶F1、F2、F3、F4羔羊不同阶段的体型外貌、体重、体尺、适应性及经济效益等指标进行观测。统计结果表明：在当地饲养管理条件下，各杂交后代的生长发育性能均优于关中奶山羊，差异显著（P〈0．05）；经济效益明显增加。因此，推广波奶杂交改良羊，对增加农民收入，推动农村经济发展意义重大。 相似文献
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饲用复合酶对杂交肉兔增重效果的影响 总被引：1，自引：0，他引：1
饲用复合酶的开发利用研究国外早在７０年代就开始进行，尤其是纤维素复合酶应用于反刍动物的研究已有大量报道。过去普遍认为纤维素酶在瘤胃中的稳定性很差（Kopecny等，１９８７），但近年来的试验研究表明，利用纤维素复合酶可提高肉牛的增重和饲料转化率（Bcanchemin等，１９９５）。国内对纤维素酶用于猪鸡效果的研究也有不少报道，结果表明可提高仔猪和肉鸡的日增重和饲料报酬。但纤维素酶应用于杂交肉兔的报道不多。为研究纤维素复合酶用于单胃草食动物的效果，我们用杂交肉兔作了有关试验，现报道于后。１材料和方法１．１酶制剂的… 相似文献
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杂交狼尾草饲养肉兔试验 总被引：1，自引：0，他引：1
以象草为对照，测定杂交狼尾草饲养肉兔的肥育效果，结果表明，试验组平均日增重肉料比，采食量均比对照组优越，相差分别为＋２３．３％，－１３．０２％和＋１３．８１％。 相似文献
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西门塔尔牛在乌鲁木齐地区冷配杂交改良效果的研究 总被引：1，自引：0，他引：1
通过调查、试验和综合分析等方法，对乌鲁木齐县西门塔尔牛冻精冷配改良当地黄牛的F1代进行杂交改良效果的研究探讨，结果表明：改良黄牛体型外貌倾向于父系．对乌鲁木齐县自然环境和饲养管理条件具有较强的适应性；初生重比当地黄牛分别增加6．5kg和6．6kg，增幅为33．8％和37．1％；各年龄段体重与当地黄牛相比提高效果极显著（P〈0．01）；24月龄体尺比当地黄牛增长效果显著（P〈0．01）；120d集中育肥后增重效果明显好于当地黄牛，差异极显著（P〈0．01）。 相似文献
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本试验就天府肉鸭（公）与四川麻鸭（母）的杂交商品鸭的饲养方式进行了初步探讨，结果表明：采用全舍式饲养杂交商品鸭比采用网上平养定时放水的饲养方式平均日增重提高１４．３％，饲料转化率提高１１．０％，每饲喂一只鸭子平均经济效益提高２７．３％，经Ｘ＾２检验，两种饲养方式其发病率无显著差异（Ｐ〉０．０５）。全舍式饲养不需放水，有利于缺少放牧水面及水源的地方发展养鸭业，具有一定的推广价值。 相似文献
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利用波尔山羊与关中奶山羊进行级进杂交,分别对波奶F1、F2、F3和F4羔羊不同阶段的体型外貌、体重、体尺、适应性及经济效益等指标进行观测。统计结果表明,在当地饲养管理条件下,各杂交后代的生长发育性能均优于关中奶山羊,差异显著（P〈0.05）,经济效益明显增加。推广波奶杂交改良羊,对增加农民收入、推动农村经济发展意义重大。 相似文献
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肉兔杂交组合试验 总被引：1，自引：0，他引：1
<正> 商品肉兔生长缓慢、饲养周期长、产肉率低,是当前我省肉兔生产中存在了一个突出问题。解决这个问题的技术措施之一是充分利用杂种优势。青紫兰兔耐粗饲、适应性强、繁殖性能好,因而是我省数量最多、分布最广的皮肉兔品种之一。但其增重速度较慢,致使经济效益不理想。鉴于上述情况,笔者于1989年以优良肉用品种比利时兔、加利福尼亚兔和新西兰白兔为父本,青紫兰兔为母本,进行了杂交试验,目的在于筛选出适合当前农村饲养条件的有效杂交组合,为利用杂种优势提高肉兔肥育性能,增加养兔农户的经济效益提供科学依据。试验结果,比x青组育肥效果最好。为了验证上述结果,于1990年进行了重复试验.现将两次试验综合报告如下。 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