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11.
将患有蹄病的牛按病情严重程度分三级,在每级中各选出12头,并将36头随机分成4组,每组共9头。第1组为对照组,第2组每头牛日粮中加35%石粉18g,第3组每头牛日粮中加硫酸锌1.2g,第4组每头牛日粮中同时加35%石粉18g和硫酸锌1.2g。同样护理,每星期对试验牛群进行修蹄及常规治疗。经过1个月的治疗第1组治愈1头,有效3头,无效5头;第2组治愈2头,有效6头,无效1头;第3组治愈3头,有效4头,无效2头;第4组治愈7头,有效2头,无效0头。卡方检测除第2、3两组差异不显著外,其他各组之间差异显著。说明在日粮中适量提高钙和锌对奶牛蹄病有良好的预防和治疗作用。  相似文献   
12.
The objective of this experiment was to determine if statistical process control (SPC) procedures coupled with remote continuous data collection could accurately differentiate between animals experimentally inoculated with a viral–bacterial (VB) challenge or phosphate buffer solution (PBS). Crossbred heifers (N = 38; BW = 230 ± 16.4 kg) were randomly assigned to treatments by initial weight, average daily gain (ADG), bovine herpes virus 1, and Mannheimia haemolytica serum titers. Feeding behavior, dry matter intake (DMI), animal activity, and rumen temperature were continuously monitored remotely prior to and following VB challenge. VB-challenged heifers exhibited decreased (P < 0.01) ADG and DMI, as well as increased (P < 0.01) neutrophils and rumen temperature consistent with a bovine respiratory disease (BRD) infection. However, none of the heifers displayed overt clinical signs of disease. Shewhart and cumulative summation (CUSUM) charts were evaluated, with sensitivity and specificity computed on the VB-challenged heifers (n = 19) and PBS-challenged heifers (n = 19), respectively, and the accuracy was determined as the average of sensitivity and specificity. To address the diurnal nature of rumen temperature responses, summary statistics (mean, minimum, and maximum) were computed for daily quartiles (6-h intervals), and these quartile temperature models were evaluated separately. In the Shewhart analysis, DMI was the most accurate (95%) at deciphering between PBS- and VB-challenged heifers, followed by rumen temperature (94%) collected in the 2nd and 3rd quartiles. Rest was most the accurate accelerometer-based traits (89%), and meal duration (87%) and bunk visit (BV) frequency (82%) were the most accurate feeding behavior traits. Rumen temperature collected in the 3rd quartile signaled the earliest (2.5 d) of all the variables monitored with the Shewhart, followed by BV frequency (2.8 d), meal duration (2.8 d), DMI (3.0 d), and rest (4.0 d). Rumen temperature and DMI remained the most accurate variables in the CUSUM at 80% and 79%, respectively. Meal duration (58%), BV frequency (71%), and rest (74%) were less accurate when monitored with the CUSUM analysis. Furthermore, signal day was greater for DMI, rumen temperature, and meal duration (4.4, 5.0, and 3.7 d, respectively) in the CUSUM compared to Shewhart analysis. These results indicate that Shewhart and CUSUM charts can effectively identify deviations in feeding behavior, activity, and rumen temperature patterns for the purpose of detecting sub-clinical BRD in beef cattle.  相似文献   
13.
AIM: To investigate the role of hydrogen sulfide (H2S) in the protection against oxidative stress in rats with chronic obstructive pulmonary disease (COPD).METHODS: The rat model of COPD was established by cigarette smoking (CS) combined with lipopolysaccharide (LPS) instillation. Thirty-two healthy male Sprague-Dawley rats were randomly divided into 4 groups: control group, CS+LPS group, CS+LPS+NaHS (H2S donor) group and CS+LPS+PPG (DL-propargylglycine, an inhibitor of cystathionine-γ-lyase) group. After 30 days, the lung functions of the rats were measured, the histological changes of lungs were observed under light microscope and the pathological scores were calculated. The H2S level in plasma and the protein expression of cystathionine-γ-lyase (CSE) in the lung tissues were measured. The content of malondialdehyde (MDA), the activity of superoxide dismutase (SOD) and catalase (CAT) were detected to reflect oxidative stress.RESULTS: Compared with control group, the peak expiratory flow (PEF) decreased by 24% and intra-pressure (IP) increased by 66% in CS+LPS group. The pathological scores of the lung tissues also increased. Compared with CS+LPS group, no change in the lung function was observed after given NaHS or PPG, but the pathological scores decreased in CS+ LPS+ NaHS group. Compared with control group, the content of H2S in plasma was increased by 26% on day 16. Compared with CS+LPS group, the content of H2S in plasma of CS+LPS+PPG group was decreased by 22% after 30 days. Compared with control group, the protein expression of CSE increased, and no statistical difference among CS+LPS group, CS+ LPS+ NaHS group and CS+LPS+PPG group was observed. Compared with control group, MDA content in the lung tissues was increased by 24% in CS+LPS group, the activity of SOD was increased by 47% and the activity of CAT was increased by 52%. Compared with CS+LPS group, the MDA content in CS+LPS+NaHS group was decreased by 21%, and no statistical difference in the activity of SOD and CAT was observed. The activity of SOD decreased by 33% after given PPG.CONCLUSION: H2S plays a role as anti-oxidant in the rats with COPD. The CSE/ H2S pathway may be involved in the development of COPD.  相似文献   
14.
山东杨树溃疡病的研究   总被引:6,自引:0,他引:6  
本文系统报道了对山东省杨树溃疡病的研究结果。主要包括溃疡病种类、分布、危害、三种主要病原菌的致病性、病害发生流行规律和溃疡病综合防治技术。山东境内杨树上发生的溃疡病共有8种,对林木造成严重危害的为杨树水泡型溃疡病、杨树烂皮型溃疡病和杨树大斑型溃疡病,其他几种溃疡病常与上述3种混合发生。在同一条件下,3种病原菌的致病强弱依次为杨树烂皮型溃疡病病原菌、杨树水泡型溃疡病病原菌、杨树大斑型溃疡病病原菌。杨树品种和水分状况是影响病害发生流行的关键因子。研究提出了选育抗病品种、注意苗木检疫、加强营林管理和适时药剂防治的一、二级综合治理杨树溃疡病的技术措施。  相似文献   
15.
李琳  马玉敏  尹荣兰  邵洪泽  许尧  许志林 《安徽农业科学》2013,41(6):2466-2467,2526
[目的]探讨吉林省德惠、农安等地区养殖场肉鸡发病的原因。[方法]通过流行病学调查、剖检病变和实验室诊断确定吉林省德惠、农安等地区养殖场肉鸡发病的原因,并提出一些综合防制措施。[结果]经流行病学调查、剖检病变和实验室诊断,确诊为非典型性新城疫继发大肠杆菌和支原体混合感染。最后,提出了相应的诊断方法和综合防制措施。[结论]该研究为肉鸡养殖中可能发生的这类疾病提供有效的防制方法和借鉴经验。  相似文献   
16.
草畜业生产方式的转变,是一项系统工程,具有复杂性和前瞻性,涉及到农、林等相关行业,与环境保护、城镇建设密切相关。本文根据当地草畜业生产实际,提出了固原市草畜业生产发展机制方面的一些创新思路。  相似文献   
17.
Inflammatory airway disease (IAD) is a common cause of poor performance, interruption of training and premature retirement in racehorses. It is also reported that up to 80% of horses are affected at some point in the first years of training in UK and Australia. However, no studies with regard to the information on occurrence of IAD in Japanese Thoroughbred racehorses have been reported. To investigate the occurrence and the characteristics of IAD, epidemic research including endoscopic examination of the airway tract and trachea wash was conducted for Thoroughbred racehorses presenting coughs or poor performance which airway tract disease was suspected stalled in training facility managed by Japan Racing Association. Fifty-six out of 76 Thoroughbred racehorses (73.7%) presenting coughing or poor performance were diagnosed as IAD. Mean incidence rate of IAD was 0.3% and it has been confirmed that constant number of IAD exists in Japan. Up to 35.7% of IAD horses showed upper airway abnormalities in some extent. There was a trend for IAD horses to use wood shavings for bedding and fed hay from the ground compared with the control group. Therefore, improvement of stabling environment may aid in preventing IAD. This study demonstrated that Japanese Thoroughbred racehorses are affected by IAD likewise other countries as well as demonstrated the characteristics of IAD which may contribute to the clarification of the pathogenesis of IAD.  相似文献   
18.
Vitamin E is a primary chain‐breaking antioxidant that prevents cyclic propagation of lipid peroxidation. Across species, vitamin E is essential for normal neuromuscular function by acting as a potent antioxidant, as well as by modulating the expression of certain genes, inhibiting platelet aggregation and stabilizing plasma membranes. This review focuses on vitamin E structure, absorption, metabolism, current equine dietary recommendations, the interplay between antioxidants and exercise, a discussion of the necessity of vitamin E supplementation in the horse above the Nutritional Research Council (NRC) 2007 requirements, and a review of equine diseases that are associated with a vitamin E deficiency. Particular emphasis is placed on the proteins involved in vitamin E absorption, transport, and metabolism as potential candidates for vitamin E‐associated diseases across species.  相似文献   
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20.
本文在调查研究凉山草坪病虫害的基础上,对草坪的病虫害防治进行了初步探讨和研究,并提出了解决途径.  相似文献   
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