舍饲散栏卷帘奶牛舍温热环境年动态研究

为了研究舍饲散栏卷帘奶牛舍温热环境年动态变化,试验采用现场检测的方法,对奶牛舍连续12个月的气温、相对湿度和风速进行检测,分析各参数及其综合指数的年变化规律。结果表明:夏季(6—8月份)舍内气温最高,每天约有12 h气温高于25℃,温湿指数每天有8.5~15.5 h超过72,奶牛遭受轻度热应激;冬季(12—2月份)舍内气温最低,但相对湿度最高(可达64.5%~81.2%)。各季节舍内的平均气温分别为8.6~15.0℃(春季)、23.1~25.3℃(夏季)、6.9~16.5℃(秋季)和-2.9~0.6℃(冬季),春、夏、秋、冬季平均风速分别为0.10~0.13,0.46~0.80,0.05~0.14和0~0.01 m/s。说明卷帘奶牛舍夏季应加强防暑降温,冬季加强通风换气。     

Annual Dynamic Research of Thermal Environment of Dairy Cowshed in Free Stall-feeding with Window

The objective of this study was to investigate the annual dynamic of thermal environment of dairy cowshed in free stall-feeding with window. Through continuous detection of the dairy cowshed for 12 months of air temperature, relative humidity and wind speed, the annual variations in these 3 parameters were analyzed. The results indicated that the indoor air temperature was high at noon and low in both the morning and evening, while the opposite tendency in the relative humidity was observed. The indoor air temperature was above 25℃ for 7.5 to 10 h daily in summer, especially in June, the indoor air temperature was higher than outdoor air temperature. In December, the indoor wind speed was almost 0 m/s. From the comprehensive index analysis, during the period of 09:30~19:30 in summer, the temperature humidity index (THI) was above 72, which made dairy cows suffer from mild heat stress. The wind chill temperature (WCT) was not below -10℃ in winter, and the dairy cows did not suffer from cold stress. In conclusion, not only heatstroke prevention in summer but also ventilation enhanced in winter for this dairy cowshed should be paid more attention.     

冀北山区散栏奶牛舍夏季风机降温效果的研究

试验旨在研究冀北山区夏季奶牛舍风机的降温效果。选择结构和饲养工艺相似的两栋舍饲散栏牛舍,分析安装风机对舍内温热环境、奶牛生理指标及产奶性能的影响。结果表明,安装风机舍的昼夜均温比对照舍低1.5℃,平均风速比对照舍高0.49 m/s,可达0.66 m/s。风机开启期间安装风机舍温湿指数(THI)显著低于对照舍(P<0.05)。此外,安装风机舍的奶牛直肠温度和呼吸频率显著低于对照舍(P<0.05),且每头牛每天产奶量比对照舍显著提高了17.0%(P<0.05),但乳脂率、乳蛋白和乳糖与对照舍相比差异均不显著(P>0.05)。由此可见,冀北山区奶牛舍安装风机可改善舍内温热环境,缓解奶牛热应激,提高奶牛的产奶性能。     

散栏奶牛舍沙土垫料微生物的年动态消长规律研究

为研究散栏奶牛舍沙土垫料微生物的年动态消长规律,试验对舍饲散栏奶牛舍双月份沙土垫料中的细菌和真菌(酵母和霉菌)数量进行连续1周的检测,并对沙土垫料中微生物数量与牛舍内温湿度进行相关性分析。结果表明:沙土垫料细菌数量随沙土铺垫时间的延长而增加,第0天时8月份沙土垫料细菌数量最高,其次是6月份,2,4,10,12月份细菌数量差异不大,第7天时达到最高;6月份和8月份在垫料中真菌数量未表现出明显的消长规律,0～6 d均呈上升趋势,第6天达到峰值;垫料中细菌和真菌数量与牛舍温度呈极显著正相关(P0.01),与环境相对湿度无显著相关性(P0.05);在相对湿度大于60%的2,10,12月份细菌增殖率高于相对湿度低于60%的4,6,8月份,真菌数量均值和增殖率最大值分别出现在炎热的8月份和6月份。     

奶牛舍内环境的控制

牛舍是奶牛生产、生活的重要环境，搞好牛舍内小环境的控制，对于保持奶牛的身体健康，提高其生产能力至关重要。现结合多年体会，分述如下：     

奶牛舍环境的建设

1 奶牛场选址奶牛场宜修建在地势高燥、背风向阳、空气流通、土质坚实、地下水位低(2米以下)、具有缓坡的北高南低的沙壤土上为好.奶牛场每天都有大量的牛奶、饲料、粪便进出.因此,应选择离饲料生产基地和放牧地较近、交通便利的地方建场,但又不能太靠近交通要道与工厂、住宅区,以利于防疫和环境卫生.一般奶牛场距交通主干道要求在300米以上,距村庄、居民区500米以上.同时,奶牛场应位于居民区下风向,以防牛舍有害气体和污水等对居民的生活造成危害.     

奶牛舍内外环境夏季气载微生物的检测

旨在比较夏季不同建筑类型奶牛舍内外气载细菌和真菌数量的变化。选择3种建筑类型的奶牛舍,采用定点采样和平板计数法对舍内、运动场、净道以及场外上风向和下风向处的气载微生物进行同期检测。结果表明:不同建筑类型和不同时间段牛舍内微生物数量均表现出显著性差异(P0.05),气载细菌和真菌总数范围分别为1.7×103~6.9×103和175~483 cfu/m3,通风好的牛舍细菌和真菌总数均较低,且一天中中午的细菌和真菌总数最高。此外,舍内细菌数量显著高于净道和运动场(P0.05),但舍内真菌总数与净道之间未表现出显著性差异(P0.05),仅显著高于运动场;多数牛场外下风向5~50 m处的细菌和真菌总数显著高于上风向处(P0.05)。本研究结果可为奶牛舍环境改善和疾病预防提供参考。     

我国奶牛舍建筑与环境控制的发展方向

环境是影响奶牛产量的主要因素之一。环境因素包括:温度、湿度、光照、风力、辐射等。当这些因素适宜     

Study on Fans Cooling of Dairy Cowshed with Free Stall in Northern Mountainous Region of Hebei in Summer

The present objective of the study was to investigate the effect of fans cooling on dairy cow in northern mountainous region of Hebei in summer.Two cowsheds with the same structure and feeding technics were used to investigate the effect of fans on indoor temperature and humidity, physiological parameters and milking performance of dairy cow.The results showed that the average ambient temperature in cowshed with fans was 1.5℃ lower than that of the control cowshed, and the average wind velocity was 0.49 m/s higher than that of the control cowshed, reaching to 0.66 m/s.Temperature-humidity index (THI) of cowshed with fans was significantly lower than that of the control shed during the period of fans running (P<0.05).Besides, the rectal temperature and respiration rate of dairy cows in cowshed with fans were significantly lower than of the control cowshed (P<0.05), and the milk yield per cow per day was 17.0% higher than that of the control cowshed (P<0.05), however, the milk fat, milk protein and milk sugar were no significant difference from the control (P>0.05).Overall, fans could decrease indoor environment, moderate heat stress and increase performance and health of dairy cows in northern mountainous region of Hebei.     

寒冷地区温室型犊牛舍温热环境研究

为研究低温条件下温室型犊牛舍内的环境状况,研究分析了舍外平均气温为（-10±1）℃、（-15±1）和（-20±1）℃条件下,温室型犊牛舍的空气温度、相对湿度、气流速度和有害气体等指标。结果表明,当外界平均气温为（-10±1）、（-15±1）和（-20±1）℃时,犊牛舍内平均气温分别为6.7℃、2.1℃和-0.6℃,平均相对湿度分别为64.1%、59.5%和75.2%,气流速度分别为0.05m/s、0.04m/s和0.04m/s,CO2浓度分别为2434mg/m3、2512mg/m3和2528mg/m3,而犊牛舍空气中未检测出H2S和NH3。结果说明,在外界平均气温-20℃以上的天气条件下,保温良好、换气充分的温室型犊牛舍,其舍内的温热环境和空气质量环境完全可以满足哺乳犊牛需要。     

Evaluation of Thermal Environment of Cowshed and Correlation Analysis Between Thermal Parameter and Physiological Parameter of Dairy Cows in Central Plain of Hebei

The purpose of this study was to evaluate thermal environment of cowshed in four seasons in central plain of Hebei,and analyze the correlation between the temperature parameters and physiological indexes of dairy cows.Three dairy cow houses with different building structures were selected,the thermal parameters (ambient temperature (Ta) and relative humidity (RH)) and physiological parameters (respiratory rate,rectal temperature and body surface temperature) were detected.The results showed that the Ta,RH and index of temperature and humidity (THI) changed significantly in four seasons (P<0.05),the average daily temperature in summer was the highest (28.59 ℃),and the average daily temperature in winter was the lowest (1.55 ℃).In summer,dairy cows were suffering from mild heat stress for 15.5 h every day,and from moderate heat stress for 6.0 h.In winter,dairy cows were under mild cold stress for an average of 12.0 h per day.The Ta and THI of three cowsheds in each season had no significant differece (P>0.05),except for that in winter.Compared with the cowshed with low wall or roller blind,the average Ta in the cowshed with only roof was 0.80-1.27 ℃ higher in summer and 1.36-1.84 ℃ lower in winter.In addition,the physiological parameters of dairy cows were extremely significantly higher in summer than those in other seasons (P<0.01).The respiration frequency or rectal temperature of cows among cowsheds in summer were significantly different (P<0.05),and the seasonal difference in body surface temperature was significant (P<0.05).Correlation analysis of thermal parameters and cow physiological parameters showed that the respiratory frequency,rectal temperature and body surface temperature were positively correlated with THI and Ta (P<0.05).However,there was no significant correlation between physiological parameters and RH (P>0.05).The results provided scientific basis for environment evaluation of cows,and physiological status of dairy cows were inferred according to environmental thermal parameters,which provided data for occurrence and early warning of stress.     

冀中平原奶牛舍温热环境评价及温热参数与生理指标的相关性分析

试验旨在评价冀中平原地区四季奶牛舍的温热环境,并分析温热参数与奶牛生理指标的相关性。选择3栋不同建筑结构的奶牛舍,对各舍温湿度和奶牛的呼吸频率、直肠温度和体表温度等生理指标进行检测。结果显示,奶牛舍四季环境温湿度和温湿指数（THI）变化显著（P<0.05）,其中夏季日均温最高,为28.59 ℃;冬季日均温最低,为1.55 ℃。奶牛夏季每天平均15.5 h遭受轻度热应激,6.0 h遭受中度热应激;冬季每天平均12.0 h遭受轻度冷应激。除冬季外,各季节不同牛舍的温度和THI均未表现出显著差异（P>0.05）。相比带矮墙或卷帘的棚舍,仅设顶子的棚舍夏季平均温度要高0.80~1.27 ℃,冬季低1.36~1.84 ℃。另外,夏季奶牛各项生理指标极显著高于其他季节（P<0.01）,且夏季不同舍奶牛的呼吸频率和直肠温度均表现出显著差异（P<0.05）,体表温度各季节差异均达显著水平（P<0.05）。从环境温湿参数与奶牛生理参数的相关性分析可看出,各项生理参数（呼吸频率、直肠温度和体表温度）与THI、环境温度均呈显著正相关（P<0.05）,但与湿度未表现出显著相关性（P>0.05）。本研究可为奶牛舍环境的评价提供科学依据,并通过环境温热参数的检测推断奶牛生理状况,为应激的发生及预警提供数据。     

肉牛舍温热环境对肉牛生理指标的影响

肉牛舍的温热环境指标如温度、相对湿度、风速,对肉牛的健康和增重有重要的影响,而且也影响着饲料的采食量及利用率。为了解肉牛舍气温、相对湿度和风速对肉牛直肠温度和呼吸率的影响,对肉牛舍温热环境指标和肉牛的生理指标进行了测定、分析。结果表明:肉牛舍内、外的6个测点,在同一时刻,温度、相对湿度指标均无显著差异(P>0.05),牛舍内、外不同测定点通风效果存在差异;新型牛舍与河南省的气候条件相适应,在豫南地区甚至河南省都可以推行。     

Evaluation on Air Environment of a Large Tower Type Cowshed for Dairy Cattle in Northern China

In this study, the air environment quality indicators of a large tower type cowshed for dairy cattle in North China were monitored and evaluated at all seasons of one year, including the indicators of thermal environment, the content of ammonia (NH₃), carbon dioxide (CO₂), microbe and the dust in the air. The objective was to study the change rules of the mentioned indicators, to evaluate whether this type of cowshed could meet the production requirements, and to provide theoretical basis for the design and daily management of the cowshed in the Northern region of China. The results showed that all the indicators mentioned above varied with seasons and time to some extent. The wind speed inside was below the standard of dairy cattle cowshed in summer, and the temperature in 14∶00 of summer was above 27 ℃, and THI was beyond 69, so the dairy cattle suffered slight heat stress in summer. The other air environment quality indicators monitored in any time and any space all met the standard. In conclusion, the tower type cowshed monitored was suitable for dairy cattle in North China, but some facilities should be added to decrease the temperature and the heat stress in summer.     

北方地区大型钟楼式奶牛舍空气环境的评价

试验对北方地区某大型钟楼式奶牛舍一年内不同季节舍内、外的空气环境指标,包括温热环境指标、CO₂和NH₃含量、空气中的粉尘和微生物含量进行测定,旨在了解其变化规律,评价其是否满足奶牛健康生产的要求,以便为北方地区奶牛舍的设计和日常管理提供理论依据。结果表明,所测指标随季节或时间均呈现出一定的变化规律;所监测奶牛舍夏季舍内风速低于标准,中午（14∶00）舍内温度超过27 ℃,温湿指数（THI）>69,奶牛在夏季产生轻度的热应激;除此以外,在不同时间、不同位点监测的其他各项空气环境指标均符合奶牛的饲养标准。综合测定结果,试验所监测的钟楼式奶牛舍较适合北方地区的奶牛养殖,但建议增加防暑降温措施,以减少奶牛在夏季产生的热应激。     

甘肃某地区奶牛运动场环境中耐药菌流行情况及相关耐药基因检测

为了解甘肃某地区奶牛运动场环境中主要耐药性细菌的分布情况及耐药基因的携带情况,试验采用抗性平板筛选法分离、纯化耐药菌后再通过16S rRNA鉴定;采用PCR方法检测6类22种耐药基因携带情况。结果显示,两年两个奶牛运动场（A和B）分离出不同种属的耐药菌共665株,经16S rRNA PCR鉴定主要为大肠杆菌、屎肠球菌和普通变形杆菌,其中耐药性大肠杆菌数量最多（398株）,A牛场耐药菌数两年相比增长28.50%,B牛场耐药菌数量持平;通过对样品进行10类药物筛选耐药菌结果显示,耐药率前3位的分别为糖肽类（11.13%,74/665）、四环素类和磺胺类（10.98%,73/665）及β-内酰胺类和氨基糖苷类（10.23%,68/665）。采用PCR方法对样品进行耐药基因检测发现,两年两个奶牛运动场的耐药基因携带情况基本相同,喹诺酮类耐药基因qnrB、qnrS的携带率分别为10.81%和83.78%,磺胺类耐药基因Sul1、Sul2和Sul3的携带率分别为100%、100%和56.76%,糖肽类耐药基因VanA、VanB和VanC的携带率分别为78.38%、100%和100%,四环素类耐药基因tetA、tetB、tetC、tetM、tetO、tetL的携带率分别为100%、100%、100%、100%、81.08%和75.68%,KPC、NDM、aac（6'）-Ⅰb-cr耐药基因的携带率分别为32.43%、29.73%及24.32%,未检出qnrC、tetK、tetW、VIM和OXA耐药基因。携带耐药基因与GenBank中登录参考株基因序列的同源性为98%~99%。甘肃地区奶牛运动场中耐药菌对常用抗菌药物普遍耐药且携带相应耐药基因,奶牛运动场中碳青霉烯类及氨基糖苷类耐药基因与上年结果相比数量增加,各相关单位人员应对其加强奶牛场中耐药菌的监测,临床治疗中应合理用药,以降低环境中耐药菌转移给人类的潜在风险。