共查询到20条相似文献，搜索用时 62 毫秒
1.
2.
3.
雏鸡、饲料和水的质量对肉鸡的生长至关重要.而肉鸡垫料的质量却很少给予足够的重视.不幸的是鸡的整个生长期内每天都要持续接触垫料.最近在营养学家和兽医专业人员之中进行的一项调查显示,90%的被调查者都表示因湿垫料所引起的问题每天都在发生.垫料的状况显著影响肉鸡的生产性能,从而最终影响养鸡的利润.垫料质量的理想状况是含水率保持在20%～25%.估算垫料水分含量的一条好的经验就是用手挤压一些垫料估算其含水率,大致可以分为以下三种情况:⑴当挤压垫料时,如果它们不能粘附在一起,说明垫料太干.⑵如果能松散的粘在一起,这时候的湿度刚好合适.⑶如果紧密的粘附在一起,形成一个团,则湿度太大. 相似文献
4.
随着肉鸡生产的迅猛发展,不少国家对如何选择理想的鸡舍垫料进行了研究。早在1968年,荷兰对鸡舍垫料进行的试验表明。理想的鸡舍垫料饲养出的肉鸡最为理想。选择肉鸡舍垫料,首先要考虑垫料的吸水性,以保持鸡舍地面干燥。一般来说,冬天鸡舍内垫料的湿度应保持在36%左右,夏天垫料混度应在18%左右.如果垫料湿度过大,则需要更换干燥的垫料,否则,过湿的垫料对肉鸡的生长发育不利,轻则使鸡羽沾染污泥,重则使肉鸡胸部出现水泡,附 相似文献
5.
随着肉鸡养殖集约化的发展,环境对肉鸡健康的影响越来越突出。湿度是肉鸡舍环境的重要指标之一,然而在肉鸡饲养生产过程中常常忽略对湿度的管理。低湿或高湿都不利于肉鸡的健康生长。加强对肉鸡舍湿度的监测及研究湿度对肉鸡健康的影响对指导鸡舍湿度的合理调控和健康养殖的发展具有重要意义。作者通过总结和分析舍内湿度对肉鸡热调节、生长性能、繁殖性能、血液指标、肉品质及呼吸道等方面的影响及舍内湿度的监测和管理方法,为深入研究湿度对肉鸡健康影响的作用机制及合理调控肉鸡舍湿度提供参考。 相似文献
6.
本试验旨在研究饲粮添加包被苯甲酸对肉鸡腿部健康和垫料理化性质的影响。选取2 400只1日龄爱拔益加肉仔鸡,随机分为2组,每组12个重复,每个重复100只(公母各占1/2)。对照组饲喂基础饲粮(颗粒料),试验组在对照组的基础上添加500 g/t包被苯甲酸。试验期为35 d。35日龄时每个重复随机抓取10只肉鸡进行脚垫和跗关节评估;收集各个重复垫料样品进行垫料湿度、p H和总氮含量的测定。结果表明:饲粮添加500 g/t包被苯甲酸显著降低了肉鸡的脚垫和跗关节损伤程度(P0.05),同时显著降低了垫料的p H和总氮含量(P0.05),对垫料湿度没有显著影响(P0.05)。由此可见,饲粮添加包被苯甲酸可降低肉鸡脚垫和跗关节损伤,同时改善垫料的理化性质,提高肉鸡饲养过程中的福利水平。 相似文献
7.
肉鸡饲养者通常着重于雏鸡、饲料和水的质量，对垫料的质量却很少给予足够的重视。生产实践证明，垫料具有许多重要的作用，垫料状况的好坏将直接影响肉鸡生产性能的发挥，从而减少肉鸡饲养者和联合体的效益。目前业内常见的垫料问题主要是潮湿问题。本文将阐述垫料潮湿的成因、危害和解决方法，供大家参考。１垫料潮湿的成因垫料潮湿一直困扰着肉鸡饲养者，其成因有很多，主要有以下几条：１．１垫料材料的特性一种有效的垫料材料必须是具有吸湿性强、轻便、价格低廉和无毒的特点。有的材料吸湿性差（稻壳），有的材料在湿度低的情况下很少… 相似文献
8.
10.
本研究旨在评估垫料类型及饲养密度对肉鸡生长性能、组织器官相对重量及肉品质的影响。试验将560只1日龄商品肉仔鸡随机分为4组，每组5个重复，每个重复28只。在为期6周的饲养试验中，T1和T2组肉鸡采用秸秆作为垫料，饲养密度分别为10和15只/cm2，T3和T4组肉鸡采用木屑作为垫料，饲养密度分别为10和15只/cm2。结果：垫料类型对肉鸡体重、日增重和采食量无显著影响（P＞0.05），但木屑组肉鸡的料重比显著低于秸秆组（P＜0.05）。在同一垫料类型条件下，饲养密度为10只/m2组肉鸡的平均日增重和采食量均显著高于饲养密度为15只/m2组（P＜0.05）。垫料类型和饲养密度对肉鸡日增重、采食量和料重比的影响具有显著交互作用（P＜0.05）。无论饲养密度如何，秸秆垫料组肉鸡的腹脂相对重量均显著高于木屑垫料组（P＜0.05），而秸秆作为垫料组的肌肉滴水损失和温度均显著高于木屑组（P＜0.05）。在同一垫料类型条件下，高密度组肌肉蒸煮损失显著低于低密度组（P＜0.05）。结论：使用木屑作为地面平养肉鸡的垫料，饲养密度为10只/m2时可改善肉鸡增重和饲料效率，降低腹脂相对重量，对肉品质无负面影响。
[关键词]垫料|饲养密度|肉鸡|生长性能|组织器官重量|肉品质 相似文献
11.
12.
13.
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
14.
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
15.
16.
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
17.
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
18.
19.
20.
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