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151.
PBL教学法在禽病学教学中的尝试   总被引:1,自引:0,他引:1  
通过分析传统禽病学教学法的不足及PBL教学法的优势,论述了PBL教学法在禽病学教学中实施情况,讨论了实施PBL教学法过程中存在的问题及对策。  相似文献   
152.
The feasibility of using GS1 DataMatrix (GS1 DM) barcodes laser printed onto the beaks of poultry as a possible method of identification and, therefore, traceability of the individual were examined in this study, including a preliminary live trial on layer hens. The optimal laser type and settings for this particular application had been selected during previous in vitro and in vivo trials. GS1 DM barcodes were printed on both sides of the beaks of mature layer hens and read using a high specification camera based 1-Dimensional/2-Dimensional (1-D/2-D) DataMan 7500 barcode reader. The reading procedure was repeated on a number of occasions over a 5 week period to examine the effects of time in a commercial environment on the clarity and readability of the GS1 DM barcode, and the ability of the printed GS1 DM barcodes to resist the physical and chemical challenges of such a setting. The results show a very short timeframe during which all barcodes, both right and left combined, remain readable. Thereafter the readability deteriorates rapidly, due to the growth and healing of the beaks of the layer hens. Results also show that there was no significant difference in the readability between GS1 DM barcodes printed on the right or left side of the beak. The proportion of identification (ι) (i.e. number of layers identifiable by either one or two readable GS1 DM barcodes) was also calculated. All layer hens were fully identifiable for a seven day period by either one or two readable GS1 DM barcodes. Further analysis showed that the proportion of identification (ι) was significantly higher for layer hens when identified with two GS1 DM barcodes as opposed to just one. Secure movement control of live mature poultry at vulnerable points in the food chain, such as transfer of ownership, could well be facilitated by the use of this technology, thereby preventing fraud or substitution at these points.  相似文献   
153.
就农村兽医在畜禽疾病防治中存在的误区进行了综述,并提出了相应的对策,旨在为农村畜禽养殖的疾病防治提供借鉴。  相似文献   
154.

Background

Farm-level biosecurity provides the foundation for biosecurity along the entire production chain. Many risk management practices are constantly in place, regardless of whether there is a disease outbreak or not. Nonetheless, the farm-level costs of preventive biosecurity have rarely been assessed. We examined the costs incurred by preventive biosecurity for Finnish poultry farms.

Methods

We used a semi-structured phone interview and obtained results from 17 broiler producers and from 5 hatching egg producers, corresponding to about 10% of all producers in Finland.

Results

Our results indicate that the average cost of biosecurity is some 3.55 eurocent per bird for broiler producers (0.10 eurocent per bird per rearing day) and 75.7 eurocent per bird for hatching egg producers (0.27 eurocent per bird per rearing day). For a batch of 75,000 broilers, the total cost would be €2,700. The total costs per bird are dependent on the annual number of birds: the higher the number of birds, the lower the cost per bird. This impact is primarily due to decreasing labour costs rather than direct monetary costs. Larger farms seem to utilise less labour per bird for biosecurity actions. There are also differences relating to the processor with which the producer is associated, as well as to the gender of the producer, with female producers investing more in biosecurity. Bird density was found to be positively related to the labour costs of biosecurity. This suggests that when the bird density is higher, greater labour resources need to be invested in their health and welfare and hence disease prevention. The use of coccidiostats as a preventive measure to control coccidiosis was found to have the largest cost variance between the producers, contributing to the direct costs.

Conclusions

The redesign of cost-sharing in animal diseases is currently ongoing in the European Union. Before we can assert how the risk should be shared or resort to the ''polluter pays'' principle, we need to understand how the costs are currently distributed. The ongoing study contributes towards understanding these issues. The next challenge is to link the costs of preventive biosecurity to the benefits thus acquired.  相似文献   
155.
我国的家禽养殖正在向精准养殖、自动化养殖、绿色养殖等方向逐步迈进。工厂化家禽养殖技术和信息化技术的协同研发和应用是促进家禽养殖行业健康可持续发展的关键,对提升家禽养殖规模化、标准化和智能化水平,提高整体产量与经济效益,促进现代化家禽养殖业的转型升级具有重要意义。本文重点围绕家禽养殖智能装备、智能算法和管控平台3个技术领域,分析了智能养殖舍、环境监测调控、智能饲喂、防疫、巡检以及无害化粪污处理等装备,家禽行为检测、盘点技术、体质量预估和健康状态评估算法,工厂化家禽养殖管控平台的最新研究应用进展以及存在的问题;指出了家禽养殖技术的薄弱环节与发展趋势,并对工厂化家禽养殖的发展和改进提出了建议,为我国现代家禽养殖业绿色高质量转型升级与健康可持续发展提供参考。  相似文献   
156.
Official post-mortem inspection records of poultry in 11 industrial poultry abattoirs in the Fars province, southern Iran, between 20 March 2002 and 19 March 2006 were used to investigate the character and prevalence of poultry loss caused by disease and pathological changes in the province. Linear regression analysis for study of time trend and χ2-test for investigation of seasonal pattern were used as statistical methods. In the study period, 130,967,021 birds were slaughtered. As a result of official veterinary inspection, 959,416 (0.73%) birds were condemned. The condemnation risk was calculated for each quarter in a year. Cachexia and septicemia were the most common reasons for rejection of carcasses and were responsible for 62% of the total condemnations. The condemnation risk due to septicemia increased over the study period from 0.14 to 0.22%. The rejection risk due to overscalding declined over the study period from 0.07 to 0.01%. No trends in time were observed for the other causes of condemnation. In conclusion the majority of condemnations are caused by disease and improving the standard of disease prevention and control on farms is necessary. These results could form the basis of an assessment of trends in condemnations in poultry slaughterhouse and should prove useful to the poultry industry as a baseline data for future comparison.  相似文献   
157.
158.
谢升凤 《古今农业》2020,(1):113-120
近年来,学术界对华南地区禽畜驯化和养殖的研究越来越多。粗略统计,发表论文约70余篇,在养牛、养猪、养鸡、养鸭及其他家养动物方面均取得一些成果.但总的来说,过去的研究还比较碎散,尚还有不少空白点,这给学术界留下了较大的空间.  相似文献   
159.
子带特征参数在家禽应激发声识别中的应   总被引:2,自引:0,他引:2  
基于子带梅尔频谱质心的优化特征参数(SMSC),研究了35日龄海兰褐蛋鸡在正常状态、光照与人为干扰等应激下发声信息的变化特征,并通过建立支持向量机模型(SVM),比较了采用优化特征参数与梅尔频标倒谱系数及其一阶、二阶导数组成的特征参数(MFCC-39)在识别不同应激中的应用效果.试验结果表明,采用加入梅尔频谱质心修正的特征参数,在分类正确识别率方面平均提高了24%.  相似文献   
160.
Subsoil compaction may reduce the availability and uptake of water and plant nutrients thereby lowering crop yields. Among the management options for remediating subsoil compaction are deep tillage and the selection of crop rotations with deep-rooted crops, but little is known of the effects of applications of organic amendments on subsoil compaction. The objectives of this study were to determine the effects of subsoil compaction on corn yield and N availability in a sandy-textured soil and to evaluate the use of deep tillage and surface applications of poultry manure to remediate subsoil compaction. A field experiment planted to corn (Zea mays L.) was conducted from 2000 to 2001 on a Reelfoot fine sandy loam (fine-silty, mixed thermic Aquic Argiudolls) formed in silty alluvium located in southeast Missouri near the Mississippi River. Treatments were arranged in a factorial design with three levels of subsoil compaction and subsoiling and four rates (averaging 0, 6, 11 and 18 Mg ha−1) of poultry manure. Subsoil tillage to a depth of 30 cm had multiple effects, including overcoming a natural or tillage-induced dense layer or pan and increasing volumetric soil water content and crop N uptake, especially in the 2001 cropping year with low early season precipitation. N recovery efficiency (NRE) was significantly higher in the subsoil treatment compared to the highest compaction treatment in 2001. No significant interactions between manure rates and compaction and subsoiling treatments were observed for corn grain and silage yields, N uptake and NRE. Average increases in corn grain yields over all manure rates due to subsoil tillage of compacted soil were 2002 kg ha−1 in 2000 and 3504 kg ha−1 in 2001. Application of poultry manure had a consistent positive effect on increasing grain yields and N uptake in 2000 and 2001 but did not significantly alter measured soil physical properties. The results of this study suggest that deep tillage and applications of organic amendments are management tools that may overcome restrictions in both N and soil water availability due to subsoil compaction in sandy-textured soils.  相似文献   
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