Growth and cocoon production by the earthworm Metaphire houletti (Oligochaeta) in different food sources

 Quantitative observations on the biology of Metaphire houletti were made in cow and horse manure and oak litter in laboratory conditions over a period of 240 days. The study revealed that copulation is not a prerequisite for production of viable cocoons, indicating that M. houletti may be parthenogenetic. The mean growth rate was 2.86 mg worm^–1 day^–1 reaching sexual maturity at 45 days and producing 0.015 cocoons worm^–1 day^–1 (kept singly) and 2.82 mg worm^–1 day^–1, reaching sexual maturity at 45 days and producing 0.03 cocoons worm^–1 day^–1 (kept in batches) in cow manure; 4.08 mg worm^–1 day^–1, reaching sexual maturity at 46 days and producing 0.02 cocoons worm^–1 day^–1 (kept singly) and 2.97 mg worm^–1 day^–1, reaching sexual maturity at 45 days and producing 0.016 cocoons worm^–1 day^–1 (kept in batches) in horse manure; 3.73 mg worm^–1 day^–1 reaching sexual maturity at 45 day and producing 0.023 cocoons worm^–1 day^–1 (kept singly) and 2.73 mg worm^–1 day^–1, reaching sexual maturity at 47 days and producing 0.028 cocoons worm^–1 day^–1 (kept in batches) in oak litter. After an incubation period of 31.9±1.2 days 82% of the cocoons hatched with a mean of 1.12±0.06 hatchlings per cocoon. The earthworms reared in batches did not demonstrate any advantage over those reared singly in all substrates. Higher growth rates were observed in earthworms raised singly than those raised in batches in all substrates. Received: 30 April 1998     

快速评茧仪的试验研究

以８０９８单片机处理机为核心组成的快速评茧仪,在设定温度条件下,能连续自动测量并显示出茧壳质量变化和相应的含水率,完成茧壳称重和分级显示。试验表明,评茧仪能够满足快速、准确评茧分级的要求。评茧仪也可用作其他物料收购、烘干及贮藏过程中含水率的快速检测。     

Evaluation of a technique to obtain development-stage-synchronised earthworms (Eisenia fetida )

 The aim of this experiment was to investigate whether Eisenia fetida hatchlings of different ages, kept initially without food, could be used to obtain worms of a comparable development stage (measured as growth) with similar maturation properties (measured as clitellum development). Seven groups of hatchlings, each differing in age by 7 days (range: 0–42 days) were collected as follows. Cocoons were kept in water in multicell containers and individuals that hatched during a 24-h period were placed on moist vermiculite with no food, at weekly intervals. The longest period that hatchlings were fasted was 42 days, after which food was added and growth monitored for 50 days. No differences in weight gain between the different batches were observed. Analysis of the growth curves and attainment of sexual maturity (clitellum development) indicated no effect of age or stage of development at the onset of feeding. It was concluded that this technique allows the production of cohorts of E. fetida, synchronised with respect to development stage, for use in toxicological and biological investigations that require control of factors such as development stage, age and size, and in particular for use in toxicological experiments complying with OECD regulatory procedures. Received: 16 June 1997     

Effect of coffee residues on growth and reproduction of Hyperiodrilus africanus (Oligochaeta, Eudrilidae) in Ivory Coast

Hyperiodrilus africanus (Beddard) is a 12-cm to 16-cm-long earthworm, which is widely distributed in West and Central Africa. It lives in the upper 10–20 cm of the soil, and feeds on a mixture of soil and above-ground litter. Cocoons obtained in the laboratory hatched on average 17 days after deposition and produced two juveniles on average. Paired individuals fed soil amended with 2% coffee residues grew significantly (P<0.05) faster than those in the control soil. Daily individual weight increments were respectively 6.1 mg worm^–1 day^–1 and 1.0 mg worm^–1 day^–1 in supplemented and control soil. The generation time was short, and cocoon production reached 9.6 month^–1 (i.e. 115 cocoons adult^–1 year^–1). When H. africanus collected from the field were raised in the laboratory, they grew slowly, laid fewer cocoons and mortality was high. Demographic parameters indicated an improvement when H. africanus were raised in batches rather than individually. Mating enhanced cocoon production although parthenogenesis was possible. Received: 4 April 1997     

家蚕地理系统间茧丝蛋白酶抑制剂含量的比较分析

以中国系统、日本系统、欧洲系统、多化性系统品种各 11个及丝胶茧 (Nd s)、裸蛹 (Nd)等为材料 ,对茧丝蛋白酶抑制剂的含量、热稳定性及与其它主要经济性状的相关性进行了研究。结果表明 :不同家蚕品种间茧丝蛋白酶抑制剂的含量差异极显著 ,且中国系统 >日本系统 >欧洲系统 >多化性系统 ,中、日、欧 3个系统的茧丝蛋白酶抑制剂含量与多化性系统间有极显著的差异 ;中系品种C12 和日系品种J12 茧丝蛋白酶抑制剂的热稳定性很强 ,欧系品种罗尼 9号和多化性品种四海茧丝蛋白酶抑制剂的热稳定性相对较弱 ;丝胶茧 (Nd s)中有少量蛋白酶抑制剂存在 ,裸蛹 (Nd)所吐的少量丝胶中无蛋白酶抑制剂存在 ;家蚕茧丝蛋白酶抑制剂的含量与茧层量、茧层率呈极显著的正相关 ,与全茧量、死笼率、幼生率、虫蛹率无显著的相关性。     

家蚕后部丝腺转氨酶活性及其与茧质性状关系

采用酶学速率法分析了８个家蚕品种末龄第３、５、７日后部丝腺谷丙转氨酶（ＧＰＴ）、谷草转氨酶（ＧＯＴ）活力和比活力。少丝量品种末龄ＧＰＴ、ＧＯＴ比活力随末龄发育逐渐升高，多丝量品种ＧＰＴ比活力随末龄发育而不断下降，而ＧＯＴ比活力一直较高或略有升高。ＧＰＴ、ＧＯＴ比活力与茧层率、茧层量、全茧量的遗传相关，末龄第３天为显著正相关，第５天相关不显著，第７天为极显著负相关。ＧＯＴ、ＧＰＴ比活力遗传力分别达８７．４４％、８０．４％，可作为产丝量选择的重要生化指标。     

茧丝学研究型教学课程建设

创新教育是目前高校人才培养的重要内容。建立研究型教学新模式和研究型课程是培养创新人才的重要方式。文章在充分认识当前茧丝学学科现状和趋势的基础上,提出从课程内容,教学方法及师资等方面进行茧丝学研究型教学课程建设。该课程的建设将强化学生的创新能力并带动茧丝学的科研发展,实现人才培养和科学研究的有机结合。     

农药苯氧威对家蚕的毒性试验

苯氧威是具有保幼激素活性的昆虫生长调节剂类杀虫剂。该药剂对家蚕的毒性试验表明无熏蒸毒性,但有一定触杀毒性,且胃毒强烈;致家蚕中毒死亡的最低浓度以及对家蚕生长发育的影响均随家蚕龄期增加而增大,从5龄第3天起连续添食稀释32万倍~16亿倍的3%苯氧威药液,可使家蚕龄期明显延长且100%不结茧。依据试验结果认为:低浓度的苯氧威虽然不能致5龄家蚕幼虫死亡,但对蚕茧生产的危害很大,该药剂用于林木害虫防治应该远离蚕区。     

日本蚕丝业行业组织的职能作用及对我国蚕丝业协会工作的启示

调查分析了近代日本蚕丝业行业组织的组织结构、管理方式、法律地位、职能行使特点及在日本蚕丝业发展中发挥的作用,总结了日本蚕丝业行业组织遵循的法律法规,以及在信息服务、市场培育、人才培养等职能作用方面值得我国蚕丝业协会工作借鉴的经验。     

我国蚕业分布与区域经济发展水平关系的探讨

通过人均GDP指标对各省市的经济发展水平进行区域归类 ,就我国经济发展与蚕业分布之间的关系进行了研究。结果表明 :蚕业分布与区域经济发展水平有较密切的关系 ;虽然蚕业在广东、江苏、浙江等地受到了挑战 ,但山东、四川、云南、广西等地却正在得到较快发展。提出 :由于地区间经济发展不平衡 ,蚕业在我国还有较大的发展空间。