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1.
为了探究不同季节猪舍环境温度、湿度和CO2浓度的变化规律,试验于2017年3,6,9,12月份分别对中国农业大学丰宁实验站规模化商品猪场空怀妊娠舍与生长育肥舍内温度、湿度和CO2浓度进行监测。结果表明:空怀妊娠舍和生长育肥舍中温度、湿度与CO2浓度呈明显季节性变化,秋季空怀妊娠舍温度最高(为24.2℃),冬季最低(为16.7℃),春季和夏季分别为18.7℃和23.0℃;秋季生长育肥舍温度最高(为21.9℃),冬季最低(为13.6℃)。空怀妊娠舍内湿度冬季最高,夏季最低。空怀妊娠舍内CO2浓度春、冬季极显著高于夏、秋季(P0.01)。一天不同时间段舍内温度呈规律性变动,为先升高后降低,而春、秋季畜舍内相对湿度先降低后升高。空怀妊娠舍内湿度与CO2浓度高度相关(P0.05或P0.01)。空怀妊娠舍秋季的温热环境指数为72.0,可加大通风量和通风频率以改善环境条件。  相似文献   

2.
张国兰  杨丽桃  王宇宸 《草业科学》2022,38(10):1890-1899
为探究典型农牧交错区大气负氧离子浓度特征,利用气压、气温、相对湿度、风速、降水量和日照时数几个气象要素及O3、SO2等空气污染物要素,揭示其中影响负氧离子浓度大小的有利及不利因子,并对比研究区内不同下垫面及环境中大气负氧离子浓度差异,以期为生态保护与经济建设共同发展提供决策思路.以内蒙古多伦县为例,重点采用Kruskal-Wallis检验及Spearman相关性分析予以研究,结果表明:1)大气负氧离子浓度全天06:00最高,14:00???15:00最低;负氧离子浓度夜间明显高于白天;不同下垫面及环境下负氧离子浓度存在统计学差异(P?相似文献   

3.
二 日温差(℃)在一天中气温在日出前最低下午2时左右最高,一天中气温最高值和最低值之差称日温差。 三相对湿度(%) 湿度是表示空气潮湿程度的物理量,亦称气湿。  相似文献   

4.
为探究典型农牧交错区大气负氧离子浓度特征,利用气压、气温、相对湿度、风速、降水量和日照时数几个气象要素及O_3、SO_2等空气污染物要素,揭示其中影响负氧离子浓度大小的有利及不利因子,并对比研究区内不同下垫面及环境中大气负氧离子浓度差异,以期为生态保护与经济建设共同发展提供决策思路。以内蒙古多伦县为例,重点采用Kruskal-Wallis检验及Spearman相关性分析予以研究,结果表明:1)大气负氧离子浓度全天06:00最高,14:00-15:00最低;负氧离子浓度夜间明显高于白天;不同下垫面及环境下负氧离子浓度存在统计学差异(P0.05),且差异随季节变化而不同。2)负氧离子浓度存在明显月际变化,6月-10月间以8月为中心基本呈正态分布,7月-8月负氧离子浓度达全年最高;12月至次年4月起伏较小。3)气温与负氧离子浓度日变化呈负相关关系,与负氧离子浓度月际变化呈正相关关系;负氧离子浓度变化与相对湿度呈正相关关系,与风速呈负相关关系,且不随时间尺度而改变;负氧离子浓度月际变化与降水量呈正相关关系,与气压、日照时数无相关性。4)负氧离子浓度日均值与空气污染物指标因子PM 10、CO、SO_2、NO_2、O_3均呈负相关关系,但四季中各相关因子随季节不同而存在差异;与PM 2.5无相关性。  相似文献   

5.
为了解广西密闭笼养舍内环境参数变化与花鸡生产性能的相关性,以广西密闭笼养花鸡为对象,从2017年11月至2018年11月,在鸡舍内的前、中、后位置中间设立监测位点,每天测定收集笼养鸡舍内环境参数包括温度、相对湿度、CO_2、NH_3、H_2S、SO_2浓度;每隔3天,在鸡舍内前、中、后位置分5点测定鸡舍内细菌数,同时记录花鸡产蛋率等生产性能。结果显示,周年内,鸡舍内平均温度和相对湿度,5~9月份比其它月份高,其中8月份平均温度最高达29.2℃,7月份平均相对湿度最高为85.12%。周年内,冬季鸡舍内CO_2、NH_3浓度最高,分别为343.64 mg/m~3和2.98 mg/m~3,夏季最低,分别为254.04 mg/m~3和0.78 mg/m~3,全年鸡舍内H2S浓度低,没有检出SO_2浓度。鸡舍内细菌总数冬季最高,达7.87×10~4cfu/m~3,全年细菌检出总数高于2.5×10~4cfu/m~3的农业行业推荐标准。周年内花鸡年平均产蛋率为60.28%,春季产蛋率最高为73.41%,冬季最低为45.55%。相关性分析结果显示,鸡舍内温度、相对湿度、CO_2和NH_3浓度与鸡舍内空气中细菌总数不相关(P0.05),温度、相对湿度与CO_2、NH_3、H_2S呈负相关关系(P0.01或P0.05),温度与鸡群产蛋率呈显著的负相关关系(P0.01),即密闭笼养舍内温度对花鸡的产蛋率有显著影响。  相似文献   

6.
<正>1通风冬天气温低,通风不当容易引起冷应激,造成鸡感冒,但不通风鸡舍内的空气污浊、氨气浓度大,病菌大量滋生更容易造成鸡群发病。专家研究发现,因通风差引发疾病的因素占到40%,可见通风的重要性。冬季通风应选择合适的方法和时间,具体方法:每天给鸡喂料时,打开鸡舍门通风,同时打开远离鸡房门一端的天窗,关闭离门口较近的天  相似文献   

7.
锡林河流域羊草群落春季CO2排放日变化特征分析   总被引:5,自引:0,他引:5  
利用静态暗箱法对具有代表性的典型温带草原的羊草群落CO2排放进行了昼夜观测。结果表明,CO2排放通量日变化与气温和地表温度呈明显的正相关关系,相关系数分别为0.7475和0.7604,而与5cm和10cm地温相关性较小,说明在干旱半干旱草原地区气温和地表温度是影响羊草群落CO2排放的关键性因子。研究还发现,羊草群落排放的CO2的近80%来自土壤呼吸、根呼吸和凋落物分解,并且春季露水对羊草草原CO2排放通量日变化特征影响显著,特别是日出前后露水的大量形成,使上午7~8时出现一次CO2排放峰值,而后CO2排放通量变化趋于与气温一致。  相似文献   

8.
旨在分析探究规模化猪场舍内颗粒物、氨气和二氧化碳的排放分布特点。试验选取了江苏省靖江市一个半封闭式现代化猪场作为试验猪场,分别监测了保育、育肥舍不同位置(南、北、前、后、外)和不同高度(0.5、1.0及1.5 m)的颗粒物(TSP、PM10、PM2.5)与NH3和CO2浓度、温度、相对湿度、光照强度以及风速等。每个舍连续监测3 d,监测时间段为07:00~19:00,每2 h监测一次,全天监测7次。结果显示:猪场舍内颗粒物与有害气体浓度随着舍内湿帘、风机开启与否及猪体的运动情况呈现出规律性的变化;喂料与风机开启阶段,颗粒物浓度呈现升高和降低的相反趋势;舍内TSP浓度及NH3浓度分别最高达到0.822 mg/m3和12.01 mg/m3。猪舍内中部位置的TSP及NH3、CO2浓度均显著性高于四周靠窗位置(P0.05);猪场舍内颗粒物(TSP和PM10)显著高于舍外(P0.05)。研究表明:半封闭式猪场舍内颗粒物与NH3和CO2呈规律性变化,通风量、温湿度及猪体的活动量等均会影响猪舍内颗粒物及NH3和CO2的浓度,舍外空气质量明显好于养殖舍内。  相似文献   

9.
锡林河流域羊草群落春季CO2排放日变化特征分析   总被引:13,自引:0,他引:13  
利用静态暗箱法对具有代表性的典型温带草原的羊草群落CO2排放进行了昼夜观测。结果表明,CO2排放通量日变化与气温和地表温度呈明显的正相关关系,相关系数分别为0.7475和0.7604,而与5cm和10cm地温相关性较小,说明在干旱半干旱草原地区气温和地表温度是影响羊草群落CO2排放的关键性因子。研究还发现,羊草群落排放的CO2的近80%来自土壤呼吸、根呼吸和凋落物分解,并且春季露水对羊草草原CO2排放通量日变化特征影响显著,特别是日出前后露水的大量形成,使上午7—8时出现一次CO2排放峰值,而后CO2排放通量变化趋于与气温一致。  相似文献   

10.
为了解广西鸡舍内主要环境因子变化对蛋鸡生产性能的影响,本试验以全封闭笼养蛋鸡舍为对象,于2018年04月-2018年5月,每天监测鸡舍内环境的温度、相对湿度、CO2、NH3、H2S、SO2浓度变化,测定点设在鸡舍的前中后位置,每隔3 d测定鸡舍内细菌的总数,并分析各种环境因子与蛋鸡生产性能的相关性。结果显示,4月份和5月份蛋鸡舍内的温度与相对湿度均呈正相关关系,与CO2和NH3浓度均呈负相关关系(P<0.01),温度在29.1℃~30.2℃时,温度与产蛋率呈显著负相关(P<0.05);日均相对湿度与日均CO2浓度均呈负相关关系(P<0.01),5月份日均相对湿度与舍内日均NH3浓度呈负相关关系(P<0.05);4月份和5月份舍内日均CO2浓度与NH3浓度呈正相关关系;舍内温度、相对湿度、CO2浓度和NH3浓度与鸡舍内环境空气细菌总量有一定相关性;鸡舍内环境空气细菌总量与日均蛋鸡淘汰率、日均破蛋率相关关系不明显。试验表明,全封闭鸡舍内温度的升高对本地蛋鸡的产蛋率有显著影响,应及时调整通风和降温措施,以免影响蛋鸡的产蛋率。  相似文献   

11.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

12.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

13.
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.  相似文献   

14.
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.  相似文献   

15.
The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.  相似文献   

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17.
An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.  相似文献   

18.
Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein  相似文献   

19.
正We are pleased to publish the second special issue on avian brood parasitism and to be responsible guest editors for the two special issues of Chinese Birds (Vol. 3, No. 4, 2012 and Vol. 4, No. 1, 2013), entitled "Avian Brood Parasitism - A Growing Research Area in Behavioral Ecology". The first issue was published in December 2012. The goal of the two special issues is to publish accumulated knowledge and some of the recent developments in  相似文献   

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