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通过对舍内外温度、湿度和风速以及舍内氨气浓度进行测定和比较,分析了我国南方地区夏季猪舍使用湿帘降温系统的防暑降温效果.结果显示:采用湿帘降温系统,在猪舍封闭性不好的情况下,降温效果不明显,舍内外温度和湿度差异不显著(P>0.05),舍内外 THI差异不显著(P>0.05);在猪舍封闭性较好的情况下,舍内外温度和湿度差异不显著(P>0.05),舍内外 THI差异显著(P<0.05);在猪舍封闭性良好的情况下,降温效果明显,舍内外温度和湿度差异极显著(P<0.01),舍内外 THI差异极显著(P<0.01).封闭性良好的猪舍内氨气浓度显著高于封闭性不好的猪舍(P<0.05),且舍内氨气浓度与风速呈负相关.调查表明,在保障猪舍封闭性良好的情况下,采用湿帘降温系统对改善夏季猪舍环境状况具有重要作用,是防暑降温的有效途径. 相似文献
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冬季养猪场的防寒管理 总被引:1,自引:0,他引:1
王春风 《畜牧兽医科技信息》2012,(8):83-84
猪舍靠外围护结构不同程度地与外界隔绝,形成不同于舍外的舍内小气候,使猪群免受酷暑严寒和风吹日晒的影响.外围护结构设计是否合理,决定了猪舍的小气候状况.
1 猪舍的保温防寒
1.1加强猪舍外围护结构的保温性能 是提高猪舍保温性能的根本措施.开放式、半开放式猪舍的温度状况受外界气温影响大,冬季一般稍高于舍外.密闭式猪舍冬季的温度状况,在舍内热量来源一定的情况下,取决于空气对流和通过围护结构散失热量的多少.失热越多,达到热平衡时舍内的温度越低,设计时可根据热工计算选择材料,以避免冬季猪舍内表面结露滴水和防止冷应激.根据猪舍的特点,猪舍外围护结构的保温性能,应在保证冬季舍内温、湿度状况下,墙和屋项(吊顶)内表面不结露. 相似文献
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蛋鸡养殖的环境控制主要包括鸡舍内、外两部分。
1舍内环境控制
舍内环境控制主要包括通风、光照、饲喂、饮水、温度、湿度、密度、选鸡和拣蛋。 相似文献
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猪舍环境中的潮湿不等于湿度,因为湿度只代表空气中水的含量,而潮湿除了空气外,更多的是地面和墙壁上湿气过重。在所有的影响猪只生长发育环境因素中,有温度、湿度、空气质量、密度等, 相似文献
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研究舍内小气候环境对肉仔鸡疾病发生的影响及改善措施。对贵州省清镇市50家共32.2万只商品肉鸡的养殖户和养殖场进行调查,并采用现场观察和询问调查相结合的试验检测方法.观察舍内湿度、氨气含量和光照等与疾病发生的关系。研究表明,改善鸡舍环境,合理控制舍内光照、温度和空气湿度以及氨气含量等环境要素.能减少疾病发生概率。提高养殖的生产力。 相似文献
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《畜牧与兽医》2017,(9):27-31
本研究旨在通过测定夏季相同时间段内新型节能猪舍与传统猪舍的环境参数,以及对猪生产性能的影响,为改善养殖环境提供参考。结果表明,在12:00时,新型节能猪舍舍内温度显著低于传统猪舍及外部环境温度(P0.05),两个类型猪舍舍内湿度显著高于外部环境湿度(P0.05);在12:00新型节能猪舍CO2浓度显著低于传统猪舍(P0.05);在8:00、12:00和18:00传统猪舍内氨气浓度都显著高于新型节能猪舍(P0.05);在12:00新型节能猪舍内部风速显著高于传统猪舍内部以及外部环境风速(P0.05)。在仔猪生长性能方面,平均日增重、饲料/增重比,节能猪舍比传统猪舍分别提高了6.18%、6.20%(P0.05)。所以,新型节能猪舍在节约能源的基础上能够在一定程度上改善猪舍内的环境。 相似文献
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家庭养殖,控制猪舍环境很重要,舍内的温度、湿度、有害气体、圈舍密度都会影响猪的发育、成长.笔者通过多年实践总结出一下几点内容,希能给各位在实践应用上有点启发. 相似文献
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秋冬季节温差大,一旦猪场管理不到位,就容易引发多种疾病,造成严重的经济损失。秋冬季节防制猪病要注意以下三个问题。1注意搞好饲养管理保持猪舍内温度相对恒定,尤其是产房和育成猪舍。产房昼夜温度要在25℃左右,护仔箱内温度不能低于30℃,育成猪舍温度不能低于22℃,在保暖的基础上做好通风换气工作,要保持舍内空气新鲜,地面干燥,防止贼风侵袭。舍内不能潮湿,湿度应控制在70%以下。在做好防寒保暖的 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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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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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