欧洲经济共同体鸡肉、鸡蛋的生产、贸易和消费动向

欧洲经济共同体(EEC)10个国家的鸡肉生产增长缓慢;由于多数成员国鸡蛋消费下降,使蛋的生产难以进展。鸡蛋的生产 EEC的鸡蛋生产面临生产性能不断改进而国内蛋需求量下降的困难。产蛋鸡数目在减少,而蛋产量下降却不明显(表1)。因此,大多数生产单     

鸡坏死性肠炎的诊断

鸡坏死性肠炎报道较少。在1985年夏季,我们曾先后在六个养鸡单位送检的病死鸡中检出该病。现就我们所见的病例发生情况、病理学与微生物学诊断以及防治情况介绍于后,供同行们参考。     

犬细小病毒性肠炎的诊断

犬细小病毒(CPV)性肠炎是犬的一种以急性出血性肠炎或急性心肌炎为主要表现的传染病.1976年以来.在吉林省延边地区传播,发病以初春和初冬两季为主。据其临床症状,病理解剖学及组织学变化、幼犬感染试验、HA和HI试验及病毒观察结果.确诊为犬细小病毒性肠炎。     

中蜂在春季多大的群势造脾快

春季多大的群势造脾快?这对科学饲养中蜂是有现实意义的问题。固然3框以下的弱群能造脾,这样的群势不但速度慢,而且消耗饲料相对地多;用8框以上的强群造脾,春季多有分蜂情绪,对巢础接受慢,甚至不接受。     

芒硝可提高蛋鸡生产性能

芒硝是兽医常用的一种泻下药,又称为硫酸钠(Na_2SO_4·10H_2O)。据一些资料记载,芒硝中的硫(S)促进含硫氨基酸、肝脏内蛋白质和核酸的生物合成,使器官中的硫基和谷胱苷肽含量增加,刺激体内的代谢过程,提高产蛋率,改善蛋的品质。同时,芒硝还参与牛磺酸的合成,其中的35S集中包含在蛋白质成分内,尤其多在蛋壳膜的卵角蛋白中,并增加输卵管组织中粘多糖类的生物合成。此外,芒硝能与有害物质酚形成轭     

我国落叶松鞘蛾的研究概况及发展方向

本综述了近20年来有关我国落叶松鞘娥的分类学、发生规律、生态学、天敌、防治技术和种群综合管理的研究结果，指出了今后的研究重点和发展方向。     

保护地二氧化碳气体变化规律与调控

保护地二氧化碳气体变化规律与调控范开业，姚富国，林同学，周建全（山东省临沂市农业局经作站）深冬，早春在保护地内进行蔬菜的栽培．对供应淡季市场，丰富城乡“菜篮子”有着显著的经济效益和社会效益。但是此时外界气温低，为保温保护设施处于密闭状态，引起棚内二氧...     

羊驼的繁殖特性

本文主要介绍了特种经济动物———羊驼的生殖生理特点、繁殖特性 ,为我国今后羊驼养殖业的发展提供理论依据     

京郊农田防护林景观生态评价--以北京大兴县北藏乡为例

Based on theories of protective forests and landscape ecology, the reasonableness of structures and patterns of shelterbelt system at Beizang Town, Daxing County, Beijing were analyzed and assessed from the two scales of forest belts and networks, by integrating uses of field investigation, GIS and RS techniques. Results showed that the existent main belt (3-12 m in width) was too narrow, while the assistant belt (3-27.1 m in width) was too wide; the species composition of the existent shelterbelts was single, and the structures and patterns of the shelterbelt system were unreasonable. It is suggested that the structure of the main and the assistant belts should be changed, such as increasing the width of main belts, decreasing the width of assistant belt, and planting more mixed species, and the pattern with arbores in the middle and shrubs in the sides of belts could be taken into account. For the landscape structure of forest network after regenerating or reconstruction, the grid number of closed network should be 13 per km2 and the minimum number of belts should be 34 per km2, This study also testified that integrating GIS and remote technique with landscape ecology could provide an effective method for reasonable reconstruction of the structures and patterns of shelterbelts system.