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1.
研究夏季内蒙古地区牛舍温热因子和奶牛行为的变化规律,为热应激防控提供依据。采用手持式环境检测仪每小时记录舍内外温湿度和风速,并记录舍内外奶牛头数、采食、饮水、站立和躺卧头数以及每头牛的呼吸评分。结果表明:(1)从0:00到24:00,牛舍内外温度和温湿度指数呈先下降后升高再下降的趋势;(2)除采食行为外,奶牛在舍内外分布、躺卧、站立和饮水行为均与舍内外温度变化有关;(3)0:00到24:00期间,舍内外奶牛平均呼吸评分基本呈先升高后下降的趋势;9:00~17:00之间,舍外奶牛呼吸评分高于舍内。综上判定,奶牛有20h处于轻度热应激、10h处于中度热应激期、1h处于严重热应激。  相似文献   

2.
为了研究我国北方夏季奶牛处于热应激的程度及热应激导致奶损失的情况,试验采用实测2013年7月中旬山西省三个规模化牛场各一栋代表性牛舍的四个位置早、中、晚的温度、湿度和收集牛场2013年DHI数据与牛场所在或周边城市气象信息,利用固定模型分析了牛舍不同时间段、不同位置的温湿度指数(THI)的差异,并粗略估计牛群夏季热应激奶损失的情况。结果表明:牛舍THI在中午(11:00—13:00)和晚上(18:00—20:00)时间段显著高于早晨(06:00—07:00),且多数时间段THI超过72,部分时间段THI超过76;在多数时间内,牛舍中间位置THI高于两边位置,且在中午时间段THI大多超过72;当地7,8月份THI接近或超过72时,群体测定日平均产奶量开始降低,即THI每升高1个单位,群体平均日产奶量约下降0.39 kg以上,且产奶量降低趋势有延迟到9月份的现象。说明夏季山西奶牛确实受到轻度热应激影响,养殖中尤其应针对牛舍重点位置在重点时间段加强防暑降温措施,减少因热应激带来的奶损失。  相似文献   

3.
为评价北京市典型奶牛舍夏季温热环境和空气质量状况,本试验分别测定了北京市郊区一典型泌乳牛舍内不同时间段(08:00—09:00,10:00—11:00,12:00—13:00,14:00—15:00,16:00—17:00,18:00—19:00)不同位置(向阳面,背阴面,饲喂通道)的温热环境因子和空气环境指标。结果表明:泌乳牛舍内温度随时间的变化先升高后降低,相对湿度先降低后升高,不同时段温湿指数(THI)均使奶牛处于热应激的水平(THI≥72);14:00—15:00风速最高,18:00—19:00 PM 2.5、PM 10、NH_3、CO_2浓度最高;向阳面风速、背阴面NH_3浓度、饲喂通道CO_2浓度极显著大于其他位置(P0.01);舍外温度、THI、NH_3浓度极显著大于舍内(P0.01),舍内风速、CO_2浓度极显著大于舍外(P0.01)。由此可得,该牛舍所测时段内奶牛均处于热应激,舍内空气流动一定程度上缓解了奶牛的热应激;舍内粉尘、NH_3和CO_2浓度符合生产标准,且向阳面空气环境指标好于背阴面和饲喂通道;比较牛舍内外温度和THI,此开放式牛舍在夏季起到了一定的隔热作用。  相似文献   

4.
为研究寒区奶牛舍温热环境的年动态变化,试验选择河北省承德市某规模化奶牛场一栋散栏有窗奶牛舍,连续12个月监测舍内外的气温、相对湿度和风速并分析其规律。结果表明,全年奶牛舍内、外气温均表现为中午高、早晚低的规律性变化,相对湿度则表现出相反的规律。夏季（6~8月）每天有7.5~10 h舍内气温高于25℃,且在6月出现了舍内气温高于舍外气温的现象。12月舍内风速几乎全天为0 m/s。从综合指数分析,夏季每天09∶30~19∶30（10 h）舍内温湿指数（THI）均超过72,奶牛处于轻度热应激状态;冬季的风寒温度（WCT）均未低于－10℃,奶牛不遭受冷应激。综合以上结果,对于寒区散栏有窗奶牛舍,夏季应加强防暑降温措施,冬季加强通风换气。  相似文献   

5.
随机选取某牧场处于热应激环境中的10头荷斯坦奶牛,对其常规生理指标中的直肠温度、呼吸数进行测量,并同时监测牛舍中的温度、相对湿度数值。分析结果表明,牛舍温度、相对湿度分别与THI呈极显著正相关和显著正相关;牛舍温度、温湿度指数的升高会导致泌乳奶牛直肠温度、呼吸频率升高,但相关性并不显著;牛舍湿度的升高会导致泌乳奶牛直肠温度、呼吸频率的下降,但相关性不显著;奶牛直肠温度与吸频率呈极显著正相关,两者之间的关系式为:直肠温度=呼吸频率×0.086+34.66。  相似文献   

6.
夏季开放式牛舍因无法实施有效的环境调控,容易造成热应激,对奶牛生产力造成不利影响。本文采用自主研发的以太网奶牛场养殖环境监控系统,对天津某牛场成乳牛舍的夏季舍内温度、相对湿度、CO2、NH3及H2S等进行了实时跟踪监测与数据采集。结果表明,7~9月份天津地区的奶牛热应激较为严重,已有的喷淋-扰流风机系统尚不足有效克服热应激对奶牛生产的影响,尤以8月份的影响最为严重,其8月份的产奶量仅为同年7月份、9月份的90%和77.4%;牛舍内的温湿指数始终处于较高水平,7~9月份的日均THI值达到76.2、80.6和73.3,与奶牛产奶量呈显著负相关,THI值每增加1,产奶量下降约0.72kg。  相似文献   

7.
热应激对上海地区奶牛生理指数和产奶量的影响   总被引：1，自引：0，他引：1  
测定牛舍室内外温湿度、泌乳牛的心跳频率、呼吸频率、直肠温度以及牛产奶量,分析热应激与奶牛生理指数和奶产量的关系。结果表明：温湿指数（THI）与心跳频率呈极显著的正相关（r=0.79〉r0.01,27）,THI与呼吸频率呈极显著的正相关（r=0.72〉r0.01,27）,THI与体温呈极显著的正相关（r=0.78〉r0.01,27）,THI与奶产量呈弱的负相关（r=-0.26）。  相似文献   

8.
试验旨在比较分析南方地区发酵床奶牛舍四个季节舍内环境卫生指标。主要测定了舍内温度、相对湿度、噪音、细菌密度、氨气浓度和温湿度指数等指标并分析了其间的相关性。结果表明:温度在四季间差异显著(P<0.05),夏季高达32.43℃,冬季低至1.53℃;春季、夏季和秋季的相对湿度显著高于冬季(P<0.05);温湿度指数(THI)在四季间差异显著(P<0.05);夏季和冬季的噪音显著高于春季和秋季(P<0.05);春季和秋季的细菌密度显著高于夏季和冬季(P<0.05);夏季氨气浓度为3.92 mg/m^3,显著高于其他季节的(P<0.05)。相关分析表明,一年中,牛舍温度与THI呈正高度相关关系(P<0.01),其余指标间相关性不高(|r|<0.70)或不相关(P>0.05)。另外,季节内的环境指标相关性分析表明:秋、冬季的温度和THI间皆呈正相关(P<0.01),冬季的温度与细菌密度呈正相关(P<0.05);春季的THI、噪音和细菌密度三者之间均呈正相关(P<0.05);秋季的氨气浓度与噪音高度也呈正相关关系(P<0.01)。综上,南方地区发酵床奶牛舍内,四季的环境卫生指标均达到了卫生标准,但夏季THI较高为85.36,奶牛易处于中度热应激状态。  相似文献   

9.
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。  相似文献   

10.
热应激对干奶期奶牛甲烷排放量的影响   总被引：2，自引：2，他引：0  
试验旨在研究不同程度热应激水平对奶牛甲烷排放量的影响。试验选用4头处于干奶期的经产中国荷斯坦奶牛,采用4×4拉丁方设计,利用环境控制舱检测温湿度指数(THI)在66、72、78和84条件下甲烷的产生量。结果表明,当奶牛处于应激状态时,CO2和CH4排放量均显著下降;单位饲料干物质所产生的甲烷量显著升高。因此,干奶期奶牛在热应激条件下,甲烷排放量显著下降。  相似文献   

11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。  相似文献   

12.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.  相似文献   

13.
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   

14.
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.  相似文献   

15.
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   

16.
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   

17.
The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.  相似文献   

18.
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   

19.
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   

20.
Infectious diseases have always been a terrible scourge for humans. The appearance of these plagues, as they were called without distinction, was generally connected to various conditions: asters, climatic changes or religious reasons. The concept of contagious, and then infectious, diseases came slowly. Variolation, i.e. transmission of ‘virulent’ matter to induce a natural disease and the immunity against it, was brought from Constantinople to England by Lady Montague, in 1721. This ‘variolation’ technique was also often performed in veterinary medicine against diseases like sheep-pox or pleuropneumonia. As ‘vaccination’ is the term generally accepted for ‘immunisation’, variolation can be the word designating such a technique. The second period of the history of immunisation began, in 1880, with the studies of Pasteur and his collaborators. A great number of bacterial vaccines were developed: dead, live but attenuated or only parts of pathogens. The viruses were produced in animals, then in eggs and at last, in tissue cultures. Second generation vaccines appeared with genetic engineering: recombinant vaccines, vector vaccines, nucleic acids vaccines, and markers vaccines, among others. These novel technologies can permit the development of new ones and improve the quality of the vaccines already existing.  相似文献   

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