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抑氨菌液改善笼养蛋鸡舍环境的效果 总被引：1，自引：0，他引：1
试验旨在研究不同频率喷洒抑氨菌液对笼养蛋鸡舍环境的影响。3间鸡舍分别饲有900只54周龄新杨褐、白羽(新杨绿、海兰灰)和海兰褐蛋鸡。试验1、2、3期分别按照3 d1次、2 d1次、1 d1次的频率以0.5%比例喷洒抑氨菌液;每天4次记录温度、湿度、NH3浓度和CO2浓度,并记录每日风机开关时间,测定硼酸吸收液中氨氮浓度和生理盐水中细菌和真菌数量。结果表明:NH3浓度、CO2浓度、吸收氨氮浓度、细菌和真菌数量不同程度地受到鸡舍内温度、湿度、风机运行时长和测定位置的影响;各环境参数受测定时风机开关状态的影响;鸡舍内NH3浓度在1~3 d内明显随鸡粪堆积时间的延长而升高;每天喷洒一次抑氨菌液能明显降低有害气体浓度。结果表明,笼养蛋鸡舍环境受多种因素的影响,每天喷洒1次抑氨菌液能明显改善舍内空气质量。结果表明,每天喷洒一次抑氨菌液能明显改善舍内空气质量。 相似文献
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AOS-80空气净化机对冬季鸡舍空气的净化作用 总被引：2，自引：0，他引：2
在有窗或无窗密闭式鸡舍中,舍内产生的有毒有害气体、微生物和粉尘对鸡的健康与生产性能有很大的影响。本研究选用AOS-80空气净化机,测定其对冬季蛋鸡舍空气的净化效果。选取尺寸、样式和饲养密度等完全相同的2栋蛋鸡舍做对比试验,2栋鸡舍通风采用自动控制装置。在试验鸡舍的屋架上按米字形均匀安装6台净化机,测定2栋鸡舍舍内有毒有害气体和空气细菌总数的浓度。结果表明:2栋鸡舍在适当通风条件下(使舍内温度维持在(15±0.1)℃,对照鸡舍和试验鸡舍的空气细菌总数平均浓度分别为33.3cfu/L和10.6cfu/L(P<0.01),净化机使之降低68.2%;NH3的平均浓度分别为1.71mg/m3和1.22mg/m(3P<0.01),净化机使之降低28.6%;H2S的平均浓度分别为0.670mg/m3和0.643mg/m3(P<0.05),净化机使之降低4.03%;蛋鸡平均周死亡率分别为0.997%和0.607%(P<0.01),净化机使之降低39.0%。本研究结果表明,舍内安装空气净化机能显著降低鸡舍空气细菌总数和有毒有害气体浓度,降低蛋鸡死亡率。 相似文献
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为了解不同笼养肉鸡舍内气载微生物浓度的变化规律,采用FA-1型六级筛孔撞击式空气微生物采样器分别对3个笼养肉鸡场鸡舍环境中气载需氧菌、气载大肠埃希菌、气载金黄色葡萄球菌、气载真菌气溶胶的浓度进行了检测。结果表明,整个养殖周期中鸡舍内气载需氧菌、气载大肠埃希菌和气载金黄色葡萄球菌浓度在鸡14日龄时最高,然后开始下降;气载需氧菌、气载大肠埃希菌和气载金黄色葡萄球菌浓度与通风条件、空舍期消毒模式、粪便清理方式等因素有关;3个鸡舍舍内气载真菌在空舍期消毒后均未检出,随着鸡日龄增长开始递增。论文为笼养鸡舍生物安全技术规程的制定奠定了基础。 相似文献
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《中国家禽》2016,(16)
为研究蛋鸡舍侧墙进风口不同位置高度对蛋鸡舍内小环境的影响,以及合理改善蛋鸡舍内气流分布的均匀性,以我国北方最常见的侧窗进风、纵向通风蛋鸡舍为研究对象,选择A、B两栋仅安装高度不同侧墙进风小窗的蛋鸡舍,侧墙小窗规格一致(宽0.65 m、高0.23 m),安装高度分别为2.25 m、1.65 m,分别测试两栋舍内温热参数以及舍内空气环境质量。结果显示:A、B两栋蛋鸡舍内平均温、湿度之间均差异不显著(P0.05),但不同走道间温、湿度存在显著差异(P0.05);两栋蛋鸡舍内测点风速、氨气平均浓度差异显著(P0.05);舍内二氧化碳平均浓度差异极显著(P0.01)。结果表明:A栋蛋鸡舍内温湿度波动低于B舍,测点风速普遍大于B栋蛋鸡舍风速,有害气体浓度低于B舍。说明侧墙进风口位置高度不仅影响蛋鸡舍内温、湿度状况,而且影响舍内污染物的分布及排除。 相似文献
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《中国畜牧杂志》2017,(5)
试验旨在研究高能光电除臭设备和光电除臭仪对鸡舍空气净化效果,为养鸡生产提供更佳的空气净化设备。首先测试2种设备对氨气的降解效果,在此基础上将设备应用于鸡舍进行空气净化效果的研究。选择建筑结构相同、饲养管理水平一致的3栋肉鸡舍,一栋作为对照(1组),不使用空气净化设备,另外两栋(2组、3组)分别使用高能光电除臭设备和光电除臭仪,在08:00—20:00每2 h运行15 min,试验期间对舍内的氨气、微粒和微生物进行测定。结果表明:在无畜无禽状态下,高能光电除臭设备在5.80(高)、3.65(中)、2.47 mg/m~3(低)的初起始浓度下,在设备运行15、30 min后,氨气的降解率分别为52.33%、50.08%、51.68%和71.04%、66.47%、57.61%;光电除臭仪在14.74(高)、6.54(中)、3.80 mg/m~3(低)的初起始浓度下,设备运行15、30 min后,氨气的降解率分别达38.89%、14.07%、23.95%和51.42%、48.74%、40.00%;在鸡舍试验期间空气净化设备显著影响舍内的空气质量,2组、3组氨气、微粒浓度均显著低于1组(P0.05),并且2组的氨气、微粒浓度显著低于3组(P0.05)。在试验中期和后期,2组和3组的微生物数量较1组显著降低(P0.05),且2组的微生物数量显著低于3组(P0.05)。因此,高能光电除臭设备和光电除臭仪均能改善鸡舍空气质量,并且前者效果优于后者。 相似文献
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固体甲醛熏蒸消毒对畜禽舍微生物气溶胶的影响 总被引：1，自引：0，他引：1
《中国兽医学报》2016,(10):1718-1721
使用国际标准的Anderson-6级空气微生物收集器检测消毒前后牛、羊、鸡、猪舍内和舍外的气载需氧菌、气载真菌和气载大肠杆菌浓度变化,并分析以上各菌种在上述收集器不同层级中的比例变化。结果显示,消毒后的动物舍内的气载需氧菌、气载真菌和气载大肠杆菌浓度均显著低于消毒前的浓度(P0.05或P0.01),消毒后的舍内以上微生物气溶胶浓度与舍外的浓度差异不显著(P0.05),且消毒后舍内的气载需氧菌、气载真菌和气载大肠杆菌在收集器5,6层级上的比例整体上呈现大幅下降的趋势。由此可见,固体甲醛熏蒸的消毒方式可有效降低畜禽舍内的微生物气溶胶浓度,且对可进入肺泡的小颗粒微生物气溶胶消毒效果更佳。 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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乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制. 相似文献
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Billinghurst RC Brama PA van Weeren PR Knowlton MS McIlwraith CW 《American journal of veterinary research》2004,65(2):143-150
OBJECTIVE: To determine whether serum concentrations of biomarkers of skeletal metabolism can, in conjunction with radiographic evaluation, indicate severity of osteochondrosis in developing horses. ANIMALS: 43 Dutch Warmblood foals with varying severity of osteochondrosis. PROCEDURE: 24 foals were monitored for 5 months and 19 foals were monitored for 11 months. Monthly radiographs of femoropatellar-femorotibial and tibio-tarsal joints were graded for osteochondral abnormalities. Serial blood samples were assayed for 8 cartilage and bone biomarkers. At the end of the monitoring period, foals were examined for macroscopic osteochondrosis lesions. RESULTS: Temporal relationships were evident between certain serum biomarkers and osteochondrosis severity in foals during their first year. Biomarkers of collagen degradation (collagenase-generated neoepitopes of type-II collagen fragments, type-I and -II collagen fragments [COL2-3/4C(short)], and cross-linked telopeptide fragments of type-I collagen) and bone mineralization (osteocalcin) were positive indicators of osteochondrosis severity at 5 months of age. In foals with lesions at 11 months of age, osteochondrosis severity correlated negatively with COL2-3/4C(short) and osteocalcin and positively with C-propeptide of type-II procollagen (CPII), a collagen synthesis marker. Radiographic grading of osteochondrosis lesions significantly correlated with macroscopic osteochondrosis severity score at both ages and was strongest when combined with osteocalcin at 5 months and CPII at 11 months. CONCLUSIONS AND CLINICAL RELEVANCE: The ability of serum biomarkers to indicate osteochondrosis severity appears to depend on stage of disease and is strengthened with radiography. In older foals with more permanent lesions, osteochondrosis severity is significantly related to biomarker concentrations of decreased bone formation and increased cartilage synthesis. 相似文献