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111.
We investigated the effects of visual and auditory information related to cow and calf stress responses at weaning. Three weaning conditions were established with physical separation only (PS), physical and visual separation (VS), and physical, visual and auditory separation (VAS). Stress responses such as vocalization and self‐grooming, and changes of three maintenance behaviors (lying, walking and grazing) were recorded for experimental cows and calves in the respective conditions. Comparison of the data revealed that the cow responses differed slightly among groups. However, the peak frequency of vocalization was higher in the PS calves than in those of either VS or VAS. Self‐grooming frequency was significantly different in calves and was high in the order of VAS, VS and PS calves. Furthermore, the percentage of time spent lying down was greater, and that of walking was less, in VAS calves than in either VS or PS calves. These results demonstrate that different information at weaning might strongly affect the stress responses of calves but not those of cows. Relative impacts of different types sensory information on stressors must be considered to plan animal‐friendly weaning.  相似文献   
112.
Previous research reported contrasting results on the effect of owner experience on dog behaviors. This may be because of dog breed genetic variability, differences in expectations, management choices, and attitude toward their dogs by owners of dogs of different breeds. A study of a single breed may help provide a better insight into this issue. A convenience sample of 94 participants, owners of 181 Argentine Dogos, was recruited to provide information on their dogs' behaviors through a questionnaire. Participants were classified according to their previous general experience or inexperience with dogs and whether they had previously owned an Argentine Dogo (expert vs. naive owners). Reasons for getting a dog (companionship, guarding, hunting, breeding) and attendance at dog-training classes were also explored. Pearson chi-square tests and binary logistic regressions were used to analyze the data. Previous inexperience with dogs was associated with a higher prevalence of dogs that were fearful of children and unknown dogs. Naive Dogo owners perceived that their dogs were more obedient and friendly toward strangers but aggressive toward children, than those belonging to Argentine Dogo experts. It also appeared that living environment and the dog's age are critical predictors of many outcome variables. Kennel living was found to be predictive of car and food protection, owner-directed aggression and aggression toward children, whereas house living was associated with fear of loud noises. Changes related to the dogs' age were probably related to behavioral development in the dogs. Destructiveness, excessive body licking, and protective aggression were more common in younger dogs, whereas aggression to unknown dogs was more common in older ones. Protective aggression was more common in males, and fear of startling noises was more common in females. Intact dogs showed a higher probability of having attention-getting behavior, and neutered dogs were more fearful of traffic. Our findings are correlative. Even if causative links cannot be made, our findings certainly provide direction for further investigation.  相似文献   
113.
以新鲜槟榔为试材,研究不同包装方式与气体成分的保鲜效果。通过测定不同时间段果实的失重率、腐烂率及粗纤维含量,得出CA处理组优于MA处理组,即通过调节环境中的02与CO2含量可以延长槟榔的保鲜期,而由腐烂率及切分后槟榔的表观可以看出,CA2-2,即网兜装槟榔,置于023%、CO220%的气调瓶贮藏,效果最佳,贮藏30d较好保持槟榔果实原有品质。  相似文献   
114.
The relative importance of breed versus rearing experience on the grazing behaviour and diet selection of beef cattle when grazing unimproved grassland was examined over 4 years. Suckler‐reared calves of a traditional (T) breed (North Devon) or a commercial (C) breed (Simmental × Hereford Friesian) were cross‐fostered and then reared either extensively (E) on unimproved grassland or intensively (I) on agriculturally improved fertilized grassland. As yearlings, the four groups of calves (Traditional breed + Extensive rearing (TE); Traditional breed + Intensive rearing (TI); Commercial breed + Extensive rearing (CE) and Commercial breed + Intensive rearing (CI)) grazed unimproved grassland dominated by Molinia caerulea, for 2 months, and foraging behaviour was studied in a test phase. There was a breed effect on total (bites + chews; TJM) jaw movement rate (T, 78·2 vs. C, 76·5 min?1; F prob. = 0·041) during grazing and on the proportion of bites taken from plant communities with sward height ≥6 cm (T, 0·83 vs. C, 0·76; F prob. = 0·018). Rearing experience affected TJM rate in the first year in July (E, 80·0 vs. I, 76·8 min?1; F prob. = 0·015) and August (E, 78·5 vs. I, 75·5 min?1; F prob. = 0·046). The intensively reared animals grew less well on average during the test phase than those that had previous experience of the unimproved grassland as calves with their mothers (E, 0·16 vs. I, 0·09 kg day?1; F prob. = 0·033). Our findings indicate that the rearing experience of livestock appears to be as important as the breed when designing grazing managements for nature conservation areas.  相似文献   
115.
叶火香 《茶叶》2014,40(4):220-222
本文通过台湾茶业考察见闻,论述台湾茶业的现状与特点,并提出今后发展茶业可参考借鉴台湾发展茶业的一些经验。  相似文献   
116.
徐文武  吕长其 《茶叶》2014,40(4):223-224
本文论述了武义县成功选育出国家级茶树品种的条件,阐述了‘春雨1号’、‘春雨2号’育种的实践过程和经验总结,为基层育种工作提供参考。  相似文献   
117.
徐秀丽  袁小青 《安徽农业科学》2014,(6):1886-1890,1899
通过回顾中国农业发展的绩效与经验,探究其对于非洲减贫和经济增长的意义,并在此基础上探究如何才能更好的加强中国农业发展的经验与中国对非农业援助实践之间的相关性.  相似文献   
118.
国外农业技术推广模式经验借鉴及启示   总被引:1,自引:1,他引:0  
介绍并分析了法国、日本、美国等发达国家的农业科学技术推广服务经验,指出了对于我国农业技术推广服务体系建设的启示,并从法律制度、组织机构体系、人才建设等方面提出了完善我国新型农村农业技术服务推广体系的相关建议。  相似文献   
119.
为探索烤烟主栽品种K326在中间香型烟叶不同产区的质量特色,通过在六省(市)的主产烟区安排田间小区试验,分析各点烟叶的外观质量、常规化学成分和感官质量.结果显示,各地区烟叶外观质量,化学成分及感官质量均存在显著差异.烟叶的外观质量以遵义、武隆和蒙阴点较好;烟叶总糖、还原糖和糖碱比以遵义、武隆和旬阳点较协调;烟碱、总氮、氯和钾氯比在各试验点均比较适宜.钾含量以桑植、遵义含量较高(高于2.0%);中部叶评吸总分和香气质以武隆、遵义和桑植较高.综合而言,K326作为6个试验点的优质品种,其中遵义和武隆更加适宜K326的生产.  相似文献   
120.
普洱茶发酵阶段色泽的变化及其与品质的关系   总被引:2,自引:1,他引:1  
为阐明普洱茶不同发酵阶段色泽变化及其与普洱茶品质的关系,研究了恒温恒湿与恒温非恒湿条件下,接种外源优势菌(酿酒酵母)与未接种外源优势菌的云南普洱茶在不同发酵阶段的感官品质、汤色的定量分析及茶色素含量的变化。结果表明:明度指数L及明度指数差ΔL与感官指标汤色的评分呈正相关;色品指数a、b及色差值Δa、Δb与汤色感官评分、滋味评分和品质总评分均呈正相关;不同发酵阶段样的ΔL、Δb的值逐渐减小,而Δa的值逐渐增大,这与其茶红素和茶黄素的值逐渐减小和茶褐素的值不断增大是一致的。普洱茶发酵阶段色泽的量化分析可作为普洱茶品质评价的重要指标,在自动化恒温恒湿条件下发酵普洱茶,有利于实现普洱茶清洁化加工和提高普洱茶品质的稳定性。  相似文献   
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