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1.
不同建筑材料猪舍围护结构的夏季隔热性能研究   总被引：3，自引：0，他引：3       下载免费PDF全文
为了寻找夏季隔热效果良好的猪舍围护结构材料,对北京市某猪场的猪舍和部分附属用房的吊顶、东墙和西墙内表面温度、舍内、舍外温度进行了监测。监测结果表明,试验期间,彩钢夹芯板屋顶+单层彩钢板吊顶、平面钢筋混凝土楼板屋顶+石膏板吊顶和彩钢夹芯板屋顶+PVC吊顶的内表面温度的最高值分别为35.3℃、32.8℃和31.2℃;24砖墙+外保温(5cm厚岩棉)东墙、24砖墙东墙和空心水泥板(10cm)+单层彩钢板(空气层17cm)东墙的内表面温度最高值分别为30.1℃、30.7℃和36.0℃;24砖墙+外保温(5cm厚岩棉)西墙、24砖墙西墙、空心水泥板(10cm)单层彩钢板(空气层17cm)西墙和单层彩钢板西墙数值分别30.2℃、31.1℃、38.8℃和44.7℃;24砖墙+外保温(5cm厚岩棉)+彩钢夹芯板屋顶+单层彩钢板吊顶和24砖墙+彩钢夹芯板屋顶+单层彩钢板吊顶的舍内温度最高值分别为35.5℃和36.0℃。在北京地区,24砖墙+外保温(5cm厚岩棉)+彩钢夹芯板屋顶+单层彩钢板吊顶和24砖墙+彩钢夹芯板屋顶+单层彩钢板吊顶的建筑形式都能起到一定的夏季隔热的作用,符合夏季猪舍隔热设计要求,两种建筑形式内的夏季最高温度均超过各阶段猪的高临界温度。  相似文献   

2.
为了探讨河北北部山区猪舍不同围护结构的夏季隔热效果,通过检测3个时间段(早上6:00—9:00,中午12:00—15:00,晚上17:00—20:00)不同墙体结构育肥猪舍的墙体内表面温度以及舍内外温湿度的连续变化,以期寻找隔热效果好的围护材料。其中舍Ⅰ为单层彩钢板屋顶+24 mm清水砖墙+3 cm泡沫保温板,舍Ⅱ为单层彩钢板屋顶+24 mm清水砖墙。结果显示:舍Ⅰ和舍Ⅱ的温湿度连续变化曲线基本一致,温度均表现为中午高、早晚低的变化规律,舍内最高温度均超过育肥猪对高温的限制要求;而相对湿度表现为中午低、早晚高的规律。早上舍Ⅰ和舍Ⅱ温度分别比舍外高4. 74和5. 52℃,差异均达极显著水平(P<0. 01);中午和晚上2种猪舍的温湿度之间以及各舍的内外温度之间均未表现出显著性差异(P>0. 05)。另外,2种猪舍的墙体内表面温度在不同时间段的变化规律基本一致,12:00—18:00温度最高,6:00—7:00温度最低,舍Ⅰ四面墙体的内表面最高温度明显低于舍Ⅱ,但均未超过围护结构夏季隔热计算温度最高值36. 3℃,符合猪舍墙体的夏季隔热设计要求。结果表明:"保温板+砖墙"结构的夏季隔热性能好于没有保温板的砖墙,本试验结果可为河北北部地区猪舍的标准化建设和改造提供数据支撑。  相似文献   

3.
监测1天中3个不同时间段(6—9时、12—15时、17—20时)不同围护结构的育肥猪舍墙体内表面温度及实时监测舍内外温湿度变化,研究冀北寒区猪舍不同围护结构墙体的冬季保温效果,以期找到保温效果优良的围护材料。研究分为对照组和试验组,试验组的墙体在对照组(单层彩钢板屋顶、24 cm清水砖墙)墙体结构基础上增设3 cm泡沫保温板。结果显示,试验组和对照组的温湿度连续变化趋势基本一致,温度均表现为中午高、早晚低的变化规律,除晚上外,试验组温度均极显著高于对照组(P<0.01),全天大部分时间的猪舍内温度适宜育肥猪所需的温度范围(13～21℃);舍内相对湿度均表现为中午低、早晚高,试验组猪舍的相对湿度平均每天有12～18 h超过75%,对照组相对湿度平均每天有16～20 h超过84.7%。此外,2种猪舍的墙体内表面温度在不同时间段的变化规律基本一致,6—7时的温度最低,试验组的4面墙体的内表面最高温度显著高于对照组(P<0.05)。结果表明,"保温板+砖墙"的冬季保温性能优于无保温板的砖墙,需要注意猪舍内早晚通风除湿。本研究可为冀北寒区猪舍的标准化建设和改造提供理论依据和实践支撑。  相似文献   

4.
1猪舍隔热 隔热是阻止舍外热量传到舍内。猪舍隔热性能的强弱取决于所用建筑材料的热阻值和蓄热性能。热阻值高、蓄热能力强的外围护结构,传入舍内的热量少,外围护结构内表面温度低,可以减少内表面对猪的热辐射,所以应选择合适的外围护结构材料和结构,保证达到理想的隔热效果。夏季太阳辐射屋顶,易将辐射热传到舍内。为了提高屋顶的隔热性能,以防署为主的地区可采用通风屋顶,即将屋顶建成2层,  相似文献   

5.
不同建筑结构屋顶的奶牛舍夏季隔热效果评价   总被引：1，自引：0，他引：1  
单彩钢屋顶奶牛舍存在热应激严重等问题，本研究对单彩钢屋顶进行外表面铺设反光膜的改进，以解决实际生产中单彩钢屋顶隔热性能差的难题。试验于2020年夏季（7—8月）比较了3类不同建筑结构屋顶（单彩钢、聚苯乙烯泡沫夹芯彩钢复合板、单彩钢+反光膜）的奶牛舍，奶牛产奶量为（30.44±3.44） kg，对外围护结构内表面温度（屋顶、料道、承重柱等）时空变化规律进行研究，并分析外围护表面温度与舍内环境温度的相关性。每周连续检测3 d，每天选择早（06:00—07:00）、午（12:00—13:00）和晚（18:00—19:00）3个时间段，试验期56d。结果表明：(1)与单彩钢舍相比，反光膜舍各围护表面温度于中午时段明显降低，尤其屋顶内表面温度降低了10.48℃（P<0.01），但各时段（早、午和晚）反光膜舍与复合板舍各围护温度未表现显著差异（早晨屋顶温度除外）；从围护结构温度的空间变化分析，反光膜舍的阳坡和阴坡屋顶温度与复合板舍之间无显著性差异，但极显著低于单彩钢舍，且反光膜舍的阳侧和阴侧料道表面温度也显著低于单彩钢舍；(2)反光膜舍和复合板舍的环境温度（Ta）于12:30—16:30较单...  相似文献   

6.
旨在研究河北省夏季不同区域羊舍外围护结构的内表面温度变化规律,并评价各区域羊舍建筑的隔热性能。选择燕山丘陵、太行山区和平原地区3大区域11栋羊舍进行外围护结构内表温度和热阻值的测定。结果表明：各区域羊舍的屋顶建筑基本符合热工建筑规范要求,但墙体的总热阻低于夏季低限热阻,不符合建筑隔热要求。从围护内表温度看,南北朝向舍各围护结构的内表温范围分别为19.59～49.54℃(屋顶)、20.21～34.34℃(墙体)和20.14～34.24℃(地面);东西朝向舍分别为25.34～44.38℃(屋顶)、30.68～36.18℃(墙体)和26.81～33.71℃(地面),且2种朝向舍的各围护结构内表面温度均表现出一定的日变化规律,早上内表面温度显著低于午、晚(P<0.05)。从不同围护结构内表面温度相关性分析,各舍均表现出不同围护结构间具显著相关性(P<0.05,r>0.7),尤其对侧围护结构间表现出强相关性(P<0.05,r>0.9),而直接关系羊群健康的地面温度与墙体也表现出强相关性(P<0.05),相关系数分别达0.904～0.959(南北朝向舍)和0.8...  相似文献   

7.
鸡舍建筑的保温隔热性能是影响鸡舍内环境的重要因素.为了解江淮流域蛋鸡养殖场鸡舍建筑的保温隔热性能,在对该地区的鸡舍建筑结构类型调查的基础上,计算并评价了常见鸡舍建筑外围护结构的保温隔热性能.结果表明,在所调查的蛋鸡养殖场鸡舍建筑样本中,封闭式鸡舍、有窗式鸡舍和卷帘式鸡舍所占的比例分别为37.5％、58.3％和4.2％,鸡舍夏季降温都采取湿帘风机系统.鸡舍墙体结构以24 cm黏土砖砌体为主,冬季舍内温度13℃、相对湿度79％时能满足保温要求,夏季能够满足隔热要求；屋顶结构以彩钢夹芯板为主,该种结构保温性能好但不能满足夏季隔热要求.因此,屋顶隔热是江淮流域蛋鸡舍建筑设计时需要考虑的重要因素.  相似文献   

8.
1）猪舍采用保温材料建造。猪舍四周墙体、房顶、地面均采用保温材料建造，冬季利于防寒，夏季利于防暑，还便于人工控制环境。保温墙体总厚度为32cm;内、外墙皆为12cm厚的砖砌成，中间夹6cm厚的低密度（10kg／m3）聚苯板或其他保温材料，内、外墙都可再粉1cm厚的水泥沙浆。保温屋顶由下至上为屋架、檩条、篷布、聚苯板、石棉瓦面（或麦秸面及其他防水屋面）。  相似文献   

9.
江波涛  李莉 《兽医导刊》2016,(20):221-222
彩钢和砖混结构肉牛舍是我国目前北方最典型的牛舍建筑方式,本试验从测试结果发现,两种育肥牛场牛舍的空气温度都未达到育肥牛适宜温度的要求(3~20℃),主要原因是牛舍外围护结构的隔热能力不够.四个肉牛舍的空气平均温度分别为2.3℃、1.0℃、-0.6℃和-11.2℃,屋顶或墙壁设置保温材料的AⅠ、AⅡ、BⅠ型舍的空气温度和内表面平均温度比外围护结构没有保温层的BⅡ型舍的都高.说明设置保温材料牛舍的气温比未设置保温材料牛舍的要高,要采用挤塑板作为保温材料时,其保温隔热效果比苯板更好些.  相似文献   

10.
试验旨在探究季节环境因素和围护结构类型对兔舍内热环境以及长毛兔生产性能、行为表现和生理指标的影响,确定长毛兔适宜的环境温度范围和嵊州地区兔舍适宜的围护结构类型。试验选取2栋不同围护结构的兔舍,舍1的墙体上1/3为60 mm厚聚苯乙烯复合彩钢板,下2/3为200 mm厚砖墙,屋顶为60 mm厚聚苯乙烯复合彩钢板;舍2墙体为200 mm厚砖墙、屋顶为100 mm厚草泥瓦。每栋舍四季均选择13只饲养在中层兔笼内的同一胎次、体重相近的健康成年长毛兔种兔,用于行为、生理和生产性能检测。结果表明：夏季高温高湿,长毛兔采食及产毛量降低（P<0.05）,耳缘和直肠温度、兔毛皮质酮（CORT）浓度、血清CORT、血清促肾上腺皮质激素（ACTH）浓度和血清过氧化氢酶（CAT）活性均升高（P<0.05）,长毛兔热应激严重;舍2夏季舍内温度低于舍1(P<0.05),兔采食量和产毛量高于舍1(P<0.05),饮水量、耳缘和直肠温度、兔毛CORT浓度和血清CAT活性低于舍1(P<0.05),兔热应激程度较轻;环境温度在16.0～25.5℃时,长毛兔耳缘和直肠温度相对稳定;嵊州地区春季...  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.
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   

13.
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   

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   

16.
Comparison of different tests to diagnose feline infectious peritonitis   总被引：1，自引：0，他引：1  
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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   

20.
Tropical Animal Health and Production -  相似文献   

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