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高飞 《江西畜牧兽医杂志》2003,(2):18-18
架子牛是指未经肥育或不够屠宰体况,年龄在4岁以内的牛。这类牛多是在较粗放的条件下饲养到2~3周岁,体重达300kg以上的牛,后出售到粮食及加工副产品多的地区进行高营养短期强度催肥,从而获得较高的日增重。催肥期视牛的情况不同,少则3个月,多则5个月。这种肥育方式充分利用牛的补偿生长能力,达到理想体重和膘情后屠宰。肥育成本低,精料用量少,经济效益较高,值得应用推广。下面笔者根据工作几年来的经验,对架子牛肥育中应注意的几个技术环节浅谈如下:1牛舍的准备购牛前1周,应将牛舍粪便清除,用水清洗后,用2%的火… 相似文献
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架子牛是指未经肥育或不够屠宰体重 ,年龄在 4岁以内的牛。这类牛多是在较粗放的条件下饲养到 2~ 3岁 ,体重达 30 0公斤以上 ,出售到粮食及加工副产品多的地区进行高营养短期强度催肥 ,从而获得较高的日增重。催肥期视牛的情况不同 ,少则 3个月 ,多则 5个月 ,这种肥育方法叫架子牛肥育 ,又叫后期集中肥育。这种肥育方式充分利用牛的补偿生长能力 ,达到理想体重和膘情后屠宰。肥育成本低 ,精料用量少 ,经济效益较高 ,值得应用推广。笔者根据几年来的实践经验 ,对架子牛肥育中应注意的几个技术环节浅谈如下 :1 购牛前的准备购牛前 1周 ,应将… 相似文献
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架子牛是指未经肥育或不够屠宰体况,年龄在4岁以内的牛。这类牛多是在较粗放的条件下饲养到2~3周岁,体重达300k以上,然后出售到粮食及加工副产品多的地区进行高营养短期强度催肥,从而获得较高的日增重。催肥期视牛的情况不同,少则3个月,多则5个月。这种肥育方式充分利用牛的补偿生长能力,达到理想体重和膘情后屠宰。肥育成本低,精料用量少,经济效益较高,值得应用推广。下面笔者根据10年的工作经验,对架子牛肥育中应注意的几个技术环节浅谈如下。 相似文献
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架子牛是指未经肥育或不够屠宰体况,年龄在4岁以内的牛。这类牛多是在较粗放的条件下饲养到2-3周岁,体重达300公斤以上,出售到粮食及加工副产品多的地区进行高营养短期强度催肥,从而获得较高的日增重。催肥期视牛的情况不同,少则3个月, 相似文献
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肉牛快速育肥是指购买15-18个月龄、体重350kg的架子牛,进行强化快速育肥,集中肥育3~4个月,充分利用牛的补偿生长能力,达到理想体重和膘情后屠宰(450~500kg).这种肥育方式具有饲养周期短、资金周转快、饲料报酬高、生产成本低、精料用量少、经济效益显著,应用较广,倍受广大养殖户的欢迎. 相似文献
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1 购牛前的准备购牛前 1周 ,应将牛舍器具进行消毒。如果是敞开式圈舍。冬季应搭塑料暖棚 ,夏季应遮荫 ,既使其通风良好 ,又使其温度不低于 5 %。2 架子牛的选购架子牛的优劣决定着肥育质量及经济效益 ,应予以充分的重视。选购架子牛应注意以下几个环节。①选好牛种。要选购用夏洛来、西门塔尔、利木赞等与本地黄牛杂交的后代 ,这样的牛肉质好 ,生长快 ,饲料报酬高。②准确判断牛的年龄。年龄较小 (1~ 3岁 )的架子牛往往容易育肥 ,肉质好、长的快、省饲料。③体貌好的牛。头要短宽 ,脊背要宽 ,体型要大 ;皮要松软、有弹性。用拇指和食指… 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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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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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
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Fractures of the anconeal process of 5 pigs ranging in age from 4 to 8 months were studied radiographically and histologically. Clinically, animals with a fracture of the anconeal process had a "tight," restricted gait. In pigs at 4.5 months of age, a radiolucent line through the base of the anconeal process was composed of fibrocartilage, fibrous connective tissue, and hyaline cartilage. Subperiosteal proliferation of woven bone was located along the cranial surface of the olecranon, adjacent to the base of the anconeal process. In older animals, the radiolucent line through the anconeal process contained variable amounts of fibrous connective tissue and fibrocartilage. The proliferation of subperiosteal bone at the base of the anconeal process formed a "buttress callus" which retained a radiolucent area between the callus and the proximal surface of the anconeal process. The latter region of radiolucency was continuous with the transversely oriented line that traversed the base of the anconeal process. 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