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61.
Zhaolong CHENG Yongtao LI Matthew Keith PINE Tao ZUO Mingxiang NIU Jun WANG 《Integrative zoology》2023,18(1):169-182
The associations between feeding activities and environmental variables inform animal feeding tactics that maximize energetic gains by minimizing energy costs while maximizing feeding success. Relevant studies in aquatic animals, particularly marine mammals, are scarce due to difficulties in the observation of feeding behaviors in aquatic environments. This data scarcity concurrently hinders ecosystem-based fishery management in the context of small toothed-cetacean conservation. In the present study, a passive acoustic monitoring station was deployed in an East Asian finless porpoise habitat in Laizhou Bay to investigate potential relationships between East Asian finless porpoises and their prey. The data revealed that porpoises were acoustically present nearly every day during the survey period. Porpoise detection rates differed between spring and autumn in concert with activities of fish choruses. During spring, fish choruses were present throughout the afternoon, and this was the time when porpoise vocalizations were the most frequently detected. During autumn, when fish choruses were absent, porpoise detection rates decreased, and diurnal patterns were not detected. The close association between fish choruses and finless porpoise activities implies an “eavesdropping” feeding strategy to maximize energetic gains, similar to other toothed cetaceans that are known to engage similar feeding strategies. Underwater noise pollution, particularly those masking fish choruses, could interrupt finless porpoises’ feeding success. Fisheries competing soniferous fishes with finless porpoise could impact finless porpoise viability through ecosystem disruption, in addition to fishing gear entanglement. 相似文献
62.
二斑叶螨寄主植物范围极广, 但其对百合科蔬菜造成危害的研究报道极少?本研究采集了来自北京海淀百合科蔬菜蒜和葱上的2个二斑叶螨种群, 生物测定结果显示, 2个种群对阿维菌素呈现出极高水平抗性, 对哒螨灵为中等以上抗性(LC50>5 000 mg/L), 对新型药剂联苯肼酯?虫螨腈和腈吡螨酯也表现出中等到高水平抗性?抗性基因突变频率检测发现, 与阿维菌素抗性相关基因G314D和G326E位点以及和哒螨灵抗性相关基因H92R位点的突变频率均高达100%, 为纯合抗性种群?因此, 本研究所测试的2个二斑叶螨种群对阿维菌素和哒螨灵单剂的敏感性极低, 需慎重选用这2种药剂, 而3种新型杀螨剂联苯肼酯?虫螨腈和腈吡螨酯在田间需轮换使用? 相似文献
63.
64.
Meat Juice Serology and Improved Food Chain Information as Control Tools for Pork‐Related Public Health Hazards 下载免费PDF全文
The seroprevalence of Salmonella spp., pathogenic Yersinia spp., Toxoplasma gondii and Trichinella spp. was studied in 1353 finishing pigs from 259 farms that were allocated according to farm types: large fattening farms (≥1000 pig places), small fattening farms (< 1000 pig places) and farrow‐to‐finish farms. The antibodies were analysed with commercial ELISA kits in meat juice samples that were collected at Finnish slaughterhouses. Salmonella antibodies were rare (3% of pigs, 14% of farms) when the cut‐off optical density (OD) value 0.2 was used. Antibodies to pathogenic Yersinia spp. and T. gondii were detected in 57% of pigs and 85% of farms (OD ≥0.3) and in 3% of pigs and 9% of farms (OD ≥0.15), respectively. No antibodies to Trichinella spp. were detected (OD ≥0.3). The European Food Safety Authority (EFSA) considers Salmonella spp., Yersinia enterocolitica, T. gondii and Trichinella spp. as the most relevant biological hazards in the context of meat inspection of pigs. The seroprevalence of these important zoonotic pathogens was low in Finland, except that of Yersinia. The seroprevalence of Toxoplasma was significantly higher in pigs originating from small‐scale fattening farms (P < 0.05). Strong positive correlation was observed at the animal level between Salmonella and Yersinia seropositivity and between Salmonella and Toxoplasma seropositivity (P < 0.05). We suggest that these results reflect the level and importance of biosecurity measures applied on the farms. Meat juice serology at slaughter is a useful tool for targeting measures to control these pathogens. The information obtained from analyses should be used as part of the food chain information (FCI). 相似文献
65.
在电力负荷管理系统中,使用反窃电监测仪,对计量回路电压,电流等实施监控主站集中监视和巡检反映窃电的方法,及时捕获窃电和提高反窃电速度。 相似文献
66.
67.
森林防火规划是森林防火工作的重要组成部分。全国一期森林防火规划实施即将结束,二期规划的编制已经启动。文章对一期规划的成效和存在的问题进行分析,藉此,对二期规划的范围、布局、重点、保障等关键问题进行阐述。 相似文献
68.
69.
总结经验 再接再厉 努力提升森林资源连续清查水平 总被引:1,自引:0,他引:1
森林资源连续清查是依法监测全国森林资源消长和生态状况变化的林业基础性工作,其成果是制定和调整经济社会发展规划和林业生态建设方针政策的重要依据。我国已经完成六次全国森林资源连续清查,积累的许多经验值得总结,更要适应生态建设的需要,进一步加以保持和发扬,并提升到新的水平。 相似文献
70.
浙江省卫星监测林火应用初报 总被引:1,自引:0,他引:1
简要介绍了浙江省卫星监测林火现状,对卫星监测林火的结果从监测精度、森林火灾的成因、分时段卫星监测森林火灾等方面进行了分析,并对卫星监测的效益和作用进行了论述。 相似文献