Studies on a year-round sericulture of Japan based on an aseptic rearing of silkworms on an artificial diet

日本的丝绸生产在5月至10月之间进行，在此期间桑叶生长。因此，每年养蚕的次数被限制在三到四次。本研究旨在与各学术领域的研究人员合作，在日本建立一个全年的蚕桑养殖体系，以激活和进一步发展日本的蚕桑产业。研究要点如下。1. 低成本人工饲料的开发。2. 一种人工饲料制备方法的建立。3. 人工饲养蚕的生理病理研究。4. 适于人工饲料饲养的蚕种的选择和放血。5. 现用蚕种人工饲料的研制。6. 全年养蚕系统的饲养效果评价。7. 全年养蚕系统的盈利能力评价。从目前的研究中，获得了以下成果…1. 研究了一种低成本的人工饲料，将豆腐渣添加到成年蚕幼虫的饲料中50%，使其在整个饲养期内消耗90%的饲料。2. 通过在阳光下晒干桑叶或从国外购买桑叶，可以降低人工饲料的成本。3. 设计了一种新的人工日粮制备方法，使日粮呈波纹状，提高了成年蚕幼虫的取食效率。4. 揭示了不完全蜕卵幼虫发生的原因。这是由于与蚕的生理和遗传有关的原因。5. 整个饲养期内三次饲喂的饲养结果如下：每个卵箱收获的茧超过30公斤。茧的长度超过1000米。未发生蚕病。丝线很有光泽。丝线的尺寸较细，为2.5旦。6. 用人工饲料一次性饲喂桑蚕幼仔，其余时间用桑叶饲养，取得了满意的结果。未发生蚕病。结果表明，在5 ~ 10月的养蚕季节，在部分饲养期内采用人工饲料进行无菌饲养是有益的。少

Silk production in Japan is carried out between May and October during which, mulberry leaves grow. As a result, the number of silkworm rearing is limited to three to four times per year. This study was aimed to establish a year-round sericulture system in Japan in cooperation with researchers with various academic fields and by which to activate and further develop sericultural industry of Japan. The points of study were as followes. 1. Development of a low-cost artificial diet. 2. Establishment of a preparation method of an artificial diet. 3. Study of physiology and pathology of silkworms reared on an artificial diet. 4. Selection and bleeding of a silkworm race suitable for rearing on an artificial diet. 5. Development of an artificial diet suitable for silkworm races now in use. 6. Evaluation of rearing results from the year-round sericulture system. 7. Evaluation of profitability of the year-round sericulture system.From the present study, the following achievements were obtained … More . 1. A low-cost artificial diet was developed by incorporating bean-curd lees in the diet as much as 50% for the grown silkworm larvae, which consumes 90% of diet fed throughout the feeding period. 2. Lowering the cost of an artificial diet was possible by drying mulberry leaves in the sun or buying mulberry leaves from abroad. 3. A new preparation method of an artificial diet was devised, which makes the diet in a form of a corrugated sheet, which improves the feeding efficiency of the grown silkworm larvae. 4. The cause of the occurrence of incompletely exuviated larva was disclosed. It was due to the cause related to physiology and genetics of the silkworm. 5. Rearing results from three times feeding throughout the feeding period are as follows. The amount of harvested cocoon was more than 30kg per one egg case. The length of a cocoon was more than 1,000m. No silkworm disease occurred. Silk thread was lustrous. The size of silk thread was thin with 2.5 deniers. 6. A one time feeding of an artificial diet to young silkworm larvae followed by mulberry leaves rearing throughout the rest of the feeding period yielded a satisfactory result. There was no occurrence of silkworm disease. This results indicate that an aseptic rearing of silkworms on an artificial diet during a part of the feeding period is useful in the rearing season of silkworms from May to October. Less