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41.
为了解国内某厂家生产的植物源中药复方消毒剂的对鸡舍现场的空气沉降菌和有害气体降解效果,试验重复3次,每次设计消毒前1h,消毒后1h、4h、10h和24h五个时间监测点,采用了细菌自然沉降法和有害气体检测仪对鸡舍内空气浮游菌含量和氨气、硫化氢等有害气体进行了检测,同时还挑选5个养殖工人对鸡舍内除臭效果感官判定。3个批次结果均显示,消毒剂按1:500和1:1000两个浓度稀释使用4h后,鸡舍现场有效除菌率就达到90%以上;消毒1h后与消毒前比较,对氨气和硫化氢的降解差异显著;消毒24h后,通过养殖工人感官评判,有显著除臭效果。结果表明,该实验设计的中药消毒剂对鸡舍内环境有显著改善作用。  相似文献   
42.
为探讨不同抗精神分裂症药物对吐鲁番斗鸡攻击行为影响的分子机理,试验将36只斗鸡随机分为12组,并选取利培酮、阿立哌唑、盐酸曲唑酮、盐酸舍曲林4种抗精神分裂症药物,且每种药物设有低剂量组(L)、正常剂量组(N)及高剂量组(H),每天人工口服给药。分别在第1、2、5、8、11、14天时,翅下静脉采血,并采用实时荧光定量PCR法对口服不同剂量药物的吐鲁番斗鸡各阶段血液中5-羟色胺转运体(5-hydroxy-tryptamine transporter,5-HTT)、色氨酸羟化酶1(tryptophan hydroxylase 1,TPH1)的mRNA表达量进行检测。结果显示,口服4种药物后,利培酮组和阿立哌唑组斗鸡血液中5-HTT、TPH1基因mRNA的表达变化具有相似性,5-HTT基因整体呈下降趋势,TPH1基因均表现为波动性上升,且利培酮组TPH1基因mRNA的表达量及上升幅度高于阿立哌唑组;盐酸曲唑酮组和盐酸舍曲林组5-HTT基因mRNA的表达均从第5天开始呈直线上升,并于第14天达到峰值,且盐酸舍曲林组TPH1基因的表达呈微上调,盐酸曲唑酮组则无明显变化。利培酮组和阿立哌唑组斗鸡攻击行为减弱与其血液中5-HTT基因mRNA的低表达有关,本试验结果为进一步研究药物影响吐鲁番斗鸡攻击行为的分子机理提供了重要参考依据。  相似文献   
43.
营地下生活的啮齿动物被誉为陆地生态系统的工程师,但其长期栖居于地下的生活习性难以被人们直接观察,给动物行为学和生态生物学等研究带来了挑战。随着科学技术的发展,无线电技术的小型化和轻量化为地下啮齿动物研究提供了可行性。国外学者已成功将无线电追踪技术应用于对地下啮齿动物洞道系统、活动节律、巢域面积变化以及社群制度等的研究。但国内将其应用于地下啮齿动物研究的较少。本文根据目前国内外研究现状,对无线追踪技术的研究内容和研究方法进行综述,以期为我国地下啮齿类研究提供参考。  相似文献   
44.
Industrial animal agriculture is grounded in the concept of maximizing productivity and profit. Selective breeding for maximum productivity in one characteristic of the animal (e.g. milk yield in cows, or breast meat in broiler chickens) has resulted in genotypes and phenotypes that may predispose the animals to poor health and welfare. The conditions in which these individuals are kept may also frustrate many inherited behaviors that they are strongly motivated to perform. In order to curb the resulting harmful aberrant behaviors, such as feather‐pecking in chickens, we sometimes resort to mutilating the animals. In many places chickens are routinely de‐beaked by means of a hot metal guillotine. Compassion in World Farming (an international organization that promotes the humane treatment of farm animals) believes that it is unethical to treat sentient beings in such ways. We have a duty to respect farm animals' sentience by providing them with housing conditions that take their needs and wants into account, and by reverting to the use of dual‐purpose, slower‐growing breeds that have the potential for good welfare. Alternatives to current farming practices are available, and we owe it to the animals, and to our consciences, to pursue them.  相似文献   
45.
对舍饲1~7日龄公骡驹的吸乳、偷乳、站立、运动、睡眠、采食、吃粪、踢、恋群、嬉耍、鸣叫、嗅舐等行为进行了观察,初步探讨了这些行为的产生原因和如何利用这些行为制定科学的骡驹培育措施。  相似文献   
46.
Rodents are globally important pre‐harvest pests of rice. In Southeast Asia, rodent damage to growing rice crops is commonly concentrated towards the center of rice fields, away from the field edge, resulting in a clear pattern known as the “stadium effect.” To further understand this behavior of rodent pests and to develop recommendations for future research and management, we examined the relation between giving‐up densities (GUDs) and damage patterns. In Tanay, Luzon, Philippines, GUD trays containing pieces of coconut in a matrix of sand were placed at 4 different distances from the field edge to quantify the perceived risk of predation in a rice field pest, Rattus tanezumi. GUDs were recorded during a dry and wet season crop at the reproductive and ripening stages of rice. In addition, assessments of active burrows, tracking tile activity and rodent damage to the rice crop, were conducted in the dry season. GUDs were significantly lower in the center of the rice fields than on the field edges, suggesting that rodent damage to rice is greater in the middle of rice fields due to a lower perceived predation risk. Furthermore, this perception of predation risk (or fear) increases towards the field edge and was greatest on the rice bund, where there was no vegetation cover. We discuss the implications for rodent management and rodent damage assessments in rice fields. This is the first documented use of GUDs in a rice agro‐ecosystem in Asia; thus we identify the challenges and lessons learned through this process.  相似文献   
47.
In equines, calls given by foals or mothers when they are seeking contact with each other or by stallions seeking contact with other group members could be classified as affiliative or separation calls when a reunion follows the vocalizations. To investigate how domestication can affect the characteristics of vocalizations produced by equines, separation calls produced by Przewalski's (Przw) horses and Mongolian domestic horses (MDH) living in the same habitat were recorded, spectrally analyzed, and compared. Species-specific acoustic differences were found in the separation vocalizations of mares and foals. In particular, the second and third formants of the calls emitted by Przw mothers were significantly higher in frequency than those emitted by Mongolian domestic mothers, whereas the same acoustical variables were significantly lower in Przw foals than Mongolian domestic foals. Second and third formants have a significant effect on discriminating separation calls emitted by mares and foals from these different equine species. With the exception of the duration of the call, no significant species-specific differences in acoustic parameters were observed in separation calls emitted by stallions. Bioacoustic analysis can discriminate 2 different species that can be affected by their environment, evolution, and social organization.  相似文献   
48.
选用35周龄伊莎蛋鸡8只,分别安装慢性颈静脉血管插管.实验采用自身对照法,对照期饲喂基础日粮,丙谷胺期在喂料前填喂丙谷胺.应用摄食行为计算机监测系统(FIDAS系统)记录各个实验期产蛋鸡喂料后4h内的采食行为数据,并测定有关血液生化指标.结果显示,实验期(填喂丙谷胺后)与对照期相比较,产蛋鸡午前(8:00~12:00)与午后(13:00~17:00)4 h内摄食量分别增加27.69%与30.41%(P<0.05),摄食时间分别降低15.67%与3.75%,摄食餐数分别增加12.32%与27.2%(P<0.05);血糖水平分别降低5.44%与18.03%(P<0.01),瘦素水平分别升高2.59%与7.19%,胰岛素水平分别升高33.09%(P<0.05)与24.5%(P<0.05).提示丙谷胺能够促进蛋鸡摄食,并影响有关内分泌激素的水平.  相似文献   
49.
The differential variables for carcass grades were identified from morphological, behavioral and physiological measurements of young steers at a commercial farm. Thirty‐five Japanese Black × Holstein steers aged 6–10 months were randomly assigned to three pens. The steers had free access to ryegrass hay and a restricted amount of concentrate diet for the first 6 months of trial. They were then given oat straw ad libitum and an additional concentrate diet until slaughter. Behavioral observations (15 categories) were carried out once every 2 weeks for 2 h after feeding. Bodyweight was measured, blood sampled (for seven metabolic hormones and five metabolites), ultrasonic scanning conducted and physical measurements taken (10 parts for each animal) in months 1, 3 and 5 (early fattening stage, EFS) and in months 7, 9 and 11 (middle fattening stage, MFS) of the trial. Temperament scores during these procedures, entry order into restraint stalls, social rank and average daily gain were also assessed. A factor analysis and one‐way anova were used to identify clusters of variables which had different factor scores between carcass grades. As for the carcass yields, a cluster of chest girth and depth, bodyweight, withers and hip height, and rump length (P < 0.01), and a cluster of the frequency of scratching the body with facilities (P < 0.05) were identified as differential variables in the EFS. In the MFS, a cluster of concentrations of cortisol and epinephrine, and the frequency of eating straw were identified (P < 0.10). As for the carcass quality grade, a cluster of social rank, triglyceride concentration and the frequencies of stand‐chewing cud and eating hay, and a cluster of the frequency of investigating facilities (both P < 0.10) were identified in the EFS. In the MFS, a cluster of hip height, bodyweight, cannon circumference, chest depth, withers height and chest girth, and a cluster of the frequencies of eating a concentrate diet and stand‐chewing the cud, and social rank (both P < 0.10) were identified. In conclusion, bodyweight, chest girth and depth, withers and hip height were identified as good differential variables for future carcass grades of young steers. Facility enrichment that encourages steers to eat hay in the EFS, and to eat a concentrate diet in and after the MFS would be effective in upgrading carcass grades. High incidence of investigating and scratching the body with facilities and stand‐chewing the cud might lead to lower carcass grades.  相似文献   
50.
以在校大学生问卷调查为例,应用联合分析法,运用极差分析、方差分析的统计学方法得出结论:价格是影响消费者酸奶购买行为的最显著因素;品牌和包装类型对酸奶购买的影响不相上下;净含量和保质期对消费者酸奶购买影响较小。乳品企业应针对不同的消费群体开发相应的产品、制定不同的市场营销策略。  相似文献   
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