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《畜牧与兽医》2015,(10):53-56
通过塑膜暖棚肉牛舍屋面形式选择、前屋面角和朝向设计、舍内其他参数确定,为北纬41°的新疆阿克苏地区塑膜暖棚肉牛舍结构标准化设计提供理论依据;同时设计了采用屋顶负压机械通风的环境调控方式时风机风量、数量及安装位置等参数,为塑膜暖棚肉牛舍屋顶负压机械通风提供一种模式。牛舍环境参数测试结果表明:在大寒当天舍内比舍外平均温度高14.2℃,舍内平均温度8.47℃,能够满足肉牛生产环境温度要求,舍内平均湿度为75.9%、CO2浓度平均为1 496 mg/m3、NH3浓度平均为2.82 mg/m3、H2S浓度平均为0.03 mg/m3,畜禽场环境质量指标符合国家标准。 相似文献
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本试验对黑龙江省砖混结构和彩钢结构肉牛舍冬季的主要温热环境和空气质量指标进行了测定和分析。结果表明,黑龙江省冬季肉牛舍温度低,平均在2.16～9.74℃;湿度大,两种牛舍的湿度都在95%以上,甚至达到饱和;舍内空气流速为0.066～0.21m/s,平均为0.159m/s;二氧化碳的平均浓度为5745～7128mg·m^-3,氨气含量平均为11.93～14.99mg·m^-3,基本到达要求的上限。两种牛舍都需要进一步提高外围结构的保温隔热能力和完善通风换气系统的设计,以减少环境因素对肉牛的直接刺激和不良影响。 相似文献
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[目的]为了解新疆阿克苏地区初冬时节肉牛舍的环境空气质量情况,对肉牛舍的环境空气质量进行了评价。[方法]对阿克苏地区具有代表性的肉牛养殖场的1栋牛舍中的CO2、NH3、CH4和H2S4种主要有害气体以及空气中的PM10、TSP进行现场测定,并对牛舍的环境空气质量进行分析评价。[结果]测定结果显示,肉牛舍的环境空气质量指标中CO2平均浓度为404mg/m3;NH3平均浓度为4.0mg/m3;CH4和H2S平均浓度<0mg/m3;PM10平均浓度为0.04mg/m3;TSP平均浓度为1.222mg/m3;CO2、NH3、CH4、H2S、PM10、TSP最高浓度和日平均浓度均低于畜禽舍的环境空气质量标准。[结论]该肉牛舍的空气质量属于清洁级别,符合肉牛养殖环境标准。 相似文献
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新疆阿克苏地区初冬时节肉牛舍环境空气质量的测定与评价 《畜牧与饲料科学》2013,34(4):9-9
[目的]为了解新疆阿克苏地区初冬时节肉牛舍的环境空气质量情况,对肉牛舍的环境空气质量进行了评价。[方法]对阿克苏地区具有代表性的肉牛养殖场的1栋牛舍中的CO2、NH3、CH4和H2S4种主要有害气体以及空气中的PMl0、TSP进行现场测定,并对牛舍的环境空气质量进行分析评价。[结果]测定结果显示,肉牛舍的环境空气质量指标中CO：平均浓度为404mg/m3;NH3平均浓度为4.0mg/m3;CH4和H2S平均浓度〈0mg/m3;PMl0平均浓度为0.04mg／m3;TSP平均浓度为1.222mg/m3;C02、NH3、CH4、H2S、PMl0、TSP最高浓度和日平均浓度均低于：畜禽舍的环境空气质量标准。[结论]该肉牛舍的空气质量属于清洁级别,符合肉牛养殖环境标准。 相似文献
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西北地区冬季肉牛舍环境指标测定与评价 总被引：2，自引：0，他引：2
试验通过测定西北地区冬季肉牛舍环境指标,评价肉牛舍环境状况并提出改进建议.选择木屋架草泥屋面肉牛舍2栋(其中1栋地面加2 cm垫料)、单层彩钢板屋面肉牛舍1栋(屋顶换气缝覆盖塑料薄膜)测定各项指标.测定结果表明:草泥屋面牛舍内平均温度为-9.56 ℃、湿度为78.71%、风速0.17 m/s,牛舍温度过低,不能满足肉牛生产要求;单层彩钢板牛舍同期的温度比草泥屋面牛舍高3 ℃,但湿度要高15%(达到93.75%),风速为0.03 m/s,其环境综合评价不如草泥屋面牛舍.牛舍地面加垫料即可提高舍内温度,又可保证地面温度在0 ℃以上,同时可以降低相对湿度4%,是改善牛舍环境条件的有效措施.建议:肉牛舍屋面采用草泥屋面或双层彩钢板,屋顶换气缝改为0.36 m,地面垫料厚度可增加到5 cm. 相似文献
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新疆北疆地区某集约化肉牛养殖场春季环境指标评价 总被引：1，自引：0，他引：1
为了解新疆伊犁地区昭苏县肉牛养殖环境状况,评价其环境质量,本研究对该县某典型集约化肉牛养殖场的相关环境指标进行了测定。采用DT-8820四合一多功能环境表(光照强度、温度、湿度、噪音)、智能气体检测报警仪(二氧化碳(CO2)、氨气(NH3)、甲烷(CH4))和LD-5C微电脑激光粉尘仪(可吸入颗粒物(PM10)和总悬浮颗粒物(TSP))对新疆昭苏县某集约化肉牛养殖场肉牛舍春季(4月下旬)上述环境指标进行为期10 d的测定。结果表明,该牛舍春季每天采光时间为08:00~18:00,约10 h;光照强度、温度、湿度和噪音平均值分别为105.61 Lux、16.30 ℃、49.56%和64.59 dB;CH4、CO2和NH3浓度平均值分别为0.09、880.91和0.51 mg/m3;PM10和TSP浓度平均值分别为0.030和0.010 mg/m3。通过对上述指标的日周期和时周期变化可发现牛舍平均温度超过国标最高限值,持续时间为11:00~24:00,约13 h。综上所述,除牛舍温度指标外,该牛舍测定的各项环境指标参数均符合畜禽养殖环境标准,该牛舍春季环境较适宜肉牛生产,但需要采取相应措施对牛舍温度进行调节以保证动物的福利需求。 相似文献
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《黑龙江畜牧兽医》2018,(24)
为探究适合东北地区的肉牛舍设计和管理方案,试验在黑龙江省选择2种具有代表性的牛舍(钟楼式彩钢结构的妊娠牛舍A和双坡式砖混结构的育肥牛舍B),对其冬季温热环境及空气质量进行测定。结果表明:牛舍A内牛只活动时平均温度为-14. 1℃,温度较低;平均相对湿度为87. 1%,较标准值略高;风速、CO_2和NH_3浓度均适宜肉牛生长。牛舍B内平均温度为-1. 6℃;平均相对湿度为100%,严重超标;舍内风速为0 m/s,CO_2和NH_3浓度较高,不利于肉牛生长。牛舍A保温层薄、门窗密封不严;牛舍B通风换气系统设计不完善是造成这些问题的主要原因。根据肉牛生长环境要求,牛舍A更适宜肉牛生长。 相似文献
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为了探讨夏季肉牛的合理饲养密度,在排除群体效应的情况下,试验采用固定动物数量、通过改变栏舍面积控制饲养密度的方法,于夏季选择初始体重在163～277 kg范围内的西门塔尔杂交小公牛32头,随机分为4组,即试验1～4组,各组间试验牛初始体重差异不显著(P0.05),设置饲养密度分别为3.0,3.6,4.5,6.0 m~2/头进行饲养试验,分别测定了试验肉牛的生产性能、动物福利水平和环境指标,并进行了相关分析。结果表明:在4种不同饲养密度下,试验牛的平均日增重(ADG)差异不显著(P0.05),试验4组的料重比最低;试验1组肉牛平均站立时间较长,为(11.84±1.07)h/d,明显高于其他试验组,但差异不显著(P0.05),而其他试验组肉牛平均站立时间之间差异不显著(P0.05);试验1组肉牛脏污评分为(2.18±0.62)分,显著高于其他试验组(P0.05);4个试验组试验期间牛舍内的平均温度、湿度及风速差异均不显著(P0.05);试验1组牛舍中CO_2浓度及NH_3浓度显著高于3,4组(P0.05)。综合考虑各项指标,建议夏季肉牛饲养密度为3.6 m~2/头更为适宜。 相似文献
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《新疆畜牧业》2020,(3)
日光暖棚牛舍由于造价低,经济效益好等原因,在我国应用非常广泛。该牛舍通过结构设计,已基本解决夏季舍内环境调控问题,但冬季存在舍内气流分布不均匀,温度较低,湿度、二氧化碳浓度较高等问题,导致肉牛生产性能降低,包括料肉比减少、日增重下降等。为了研究日光暖棚牛舍内主要环境参数在不同时间段和不同高度上的时空分布规律,以指导该牛舍结构和环境调控系统的优化设计,本文在现场实测的基础上,采用计算流体动力学CFD(Computational fluid dynamics)方法对牛舍内温度场进行模拟和分析,并对温度、湿度、CO_2浓度、NH_3浓度在牛舍内不同高度和不同时间实测值进行方差分析。冬季塑料薄膜覆盖牛舍主要调控因素为湿度和CO_2浓度。该牛舍内最需要环境调控的位置是距离地面3m高度处,时间是0:00～4:00。该研究可为日光暖棚牛舍结构和环境调控系统优化设计提供理论依据。 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