Perch Arrangements in Small-Group Furnished Cages for Laying Hens

In 2 trials, including 2,768 birds in total, 3 different perch arrangements were evaluated in furnished 8-hen cages for laying hens. The hybrids used were Lohmann Selected Leghorn and Lohmann Brown in trial 1 and Hy-Line White and Hy-Line Brown in trial 2. The furnished cages were identical in all other respects than the arrangement of perches. A perch was either fitted across the cage, providing 12 cm of perch per hen, or 2 perches were installed in a cross, implying 15 cm per hen. Although the perches arranged in a cross provided more perch per hen than the single perch fitted across the cage, perch use at night by the birds was similar or lower as compared with the single perch. Hence, the way perches are arranged in the cage may be as important as perch length itself to achieve a high use at night. Perch arrangement did not affect production, mortality, or egg quality. Compared with a conventional battery cage, also included in the trials, hygiene was inferior in the furnished cages, but there was no difference in proportions of dirty eggs. Differences in proportions of cracked eggs were found between furnished and conventional cages in 1 of the trials. However, on the whole, production, mortality, and egg quality were at similar levels in all cage models. Genotype differences were found in production traits, egg quality, hygiene, and in the use of perches and nests.     

Determinants of litter accumulation and the abundance of litter-associated microarthropods in bird's nest ferns (Asplenium nidus complex) in the forest of Yambaru on Okinawa Island, southern Japan

We studied the distributional pattern of bird's nest ferns (Asplenium nidus complex) and the factors that determined litter accumulation and the abundance of litter-associated microarthropods in the ferns in the forest of Yambaru on the northern part of Okinawa Island, southern Japan. We located 53 bird's nest ferns (41 ferns on 27 live trees of 13 species, and 12 on 5 dead trees) in a ca. 4-ha plot, collected litter samples from 37 ferns on 25 live trees, and then extracted a total of 11 205 microarthropods (Acari and Collembola) from all the litter samples. The ferns preferred concave slopes and tended to be distributed on the tree species that had the typical characteristics of high population density and/or large basal area in the forest. The ferns were usually established on large trees [≥10 m high or ≥20 cm diameter at breast height (DBH)], although the number and size of the ferns were not related to the size of the host trees. The amount of litter accumulated in the ferns was correlated neither with the size (height and DBH) of the host tree nor with the height and position of the ferns. The amount of accumulated litter had a significant positive correlation only with fern size; this might have caused the positive correlations between fern size and the abundance of litter-associated microarthropods and the number of species of oribatid mites in the ferns.     

互利共生关系下粗纹举腹蚁蚁巢及种群的时空动态

紫胶种植园中的粗纹举腹蚁与云南紫胶虫之间存在互利共生关系,为了揭示粗纹举腹蚁蚁巢和种群的时空分布,于2009年11月至2010年7月在云南省墨江县雅邑乡的紫胶林和对照林内分别调查了粗纹举腹蚁巢的数量、空间位置和体积,记录了蚁巢数量和工蚁数量的时间动态变化。结果表明:紫胶林中的蚁巢数量和工蚁数量均显著高于对照林;蚁巢的集群分布、随机分布和离散分布模式在研究样地内均有出现,但紫胶林中的随机分布频率高于对照林;蚁巢数量与工蚁数量随月份变化,紫胶虫成虫期的工蚁数量略高于紫胶虫幼虫期。本研究结果表明蚂蚁与紫胶虫的互利共生改变了蚁巢的分布模式,增加了蚂蚁的种群数量,为在紫胶种植园中利用粗纹举腹蚁进行生物防控提供了一定的生物学依据。     

阳新仙岛湖风景区生态环境建设与保护对策探讨

阳新仙岛湖是省级生态旅游风景区,随着旅游景点的开发,景区资源破坏、生态脆弱、环境质量下降的问题日益突出,景区生态环境建设亟待加强。笔者对仙岛湖风景区生态环境的现状、问题及保护与建设对策进行了探讨,对指导仙岛湖风景区生态环境建设有着重要意义。     

基于高通量测序技术的燕窝罐头腐败嗜热菌分析

为了研究燕窝罐头生产过程微生物结构的变化,同时筛查出造成燕窝罐头安全隐患的嗜热微生物,该研究通过16S rRNA高通量测序技术结合传统培养分离方法研究燕窝生产中燕窝原料、冰糖原料、蒸煮锅糖液、灌装车间毛巾、灌装口糖液、挑毛车间毛巾、汽蒸后燕窝、灌装后产品的微生物组成.Alpha多样性研究结果表明灌装工序是微生物可能显著...     

俄罗斯空间植物学研究进展

本综合分析了俄罗斯在空间植物学研究方面的最新进展,包括空间搭载种子在地面的萌发和生长发育、植物在空间飞行环境的生长发育,以推动有关研究工作在我国的开展。     

嘉陵江北碚江段人工鱼巢增殖效果调查

为探索人工鱼巢的增殖效果,于2014年2月15日—4月20日,在嘉陵江北碚江段郭家沱和三圣庙产卵场投放人工鱼巢对该区域产黏性卵鱼类进行增殖。结果显示:在两水域人工鱼巢上产卵的为鲤(67.2%)和鲫(32.8%),产卵集中在3月中旬-4月上旬,产卵均有4次峰值,分别粘附鱼卵814.6万和2 194.6万粒;推算本研究投放的人工鱼巢至少可为200组鲤、520组鲫亲鱼提供繁殖场所,增殖鲤58.0万尾、鲫28.4万尾,增加鲤400.4 t、鲫8.7 t,经济价值达491万元。     

人工鱼巢及其在渔业资源增殖中的作用

为了进一步促进人工鱼巢技术研究的深入开展和渔业资源增殖技术的推广应用,笔者综述了国内外人工鱼巢养殖技术的发展概况,并系统汇总了国内外不同类型人工鱼巢在渔业资源增殖中的研究实例,阐明了人工鱼巢养殖技术的增产增效作用,并对国内外人工鱼巢的类型、构造、材质进行了总结归纳,提出了人工鱼巢的选址、建设、管理等要求,展望了人工鱼巢的发展前景并指出了人工鱼巢技术的重点研究方向。     

Rapid assessment of orangutan density

In order to design effective conservation measures for the orangutan, accurate information on their distribution and densities are needed. Nest counts along line transects allow for fairly accurate assessment of orangutan density. However, large sample sizes are needed to obtain accurate estimations of the decay rate of nests, preventing a rapid estimate. Moreover, due to the structure of tropical forests, nest numbers above and near the trail are underestimated. In this study, a rapid assessment method for the estimation of orangutan density is developed, allowing for the estimation of density with a single survey. Procedures are provided for estimating a correction factor which adjusts for underestimating nest numbers near the transect trail. Furthermore, we provide a shortcut to rapidly assess nest decay rate without the need for consecutive surveys. Finally, recommendations are made for determining orangutan density using two different techniques. These techniques incorporate correction factors and a shortcut to accurately assess orangutan density with only one or two visits to an area.     

废弃物生产地毯式草皮的研究

以废弃物为铺网进行地毯式草皮培植及其铺坪建植,并对培植草皮、草皮铺坪建植性能指标进行了研究.结果表明,由于同草种废弃物铺网不同,培植草皮性能差异相对较大,铺网生产性能差异相对较小;除个别废弃物外,多数废弃物生产地毯式草皮均十分理想.草种不同,草皮及铺坪效果也不同.因此,生长快、根系发达并对铺网适应性好的草种是理想草种.