| It is an epoch-making technical innovation in sericulture history to rear silkworm with artificial diet. Rearing silkworm with artificial diet has unique superiority over mulberry leaf rearing. It is also the major direction in the future development of sericulture in China. However, there are still lots of unsolved problems left in whether theory or practical utilization now. There are main obstacles to restricting the practical use of rearing young silkworm with common artificial diet in our country, such as high diet cost, trivial details of diet processing and preparation, extremely difficult rearing technique, poor feeding habit of silkworm, difficulty in reservation and transportation of diet and no special purpose silkworm variety etc. This paper studied the effect of processing craft on nutritious ingredients of pellet artificial diet, the effect of the feeding habit and digestibility and utilization as well as influential factors of silkworm, the author also discussed the way of modulating of diet, rearing technique and the practical use of rearing young silkworm with pellet artificial diet etc. The main results are as follows.1. When artificial diet was processed into pellet forms, the available ingredients for silkworm were destroyed a little. Results showed that there was no remarkable change in content of crude protein. Preservation of Vc of pellet artificial diet was high, but content of crude fat was low compared with cooking artificial diet.2. Digestibility and absorption of crude protein of rearing silkworm with pellet artificial diet was higher than that of cooking diet, while crude fat was opposite. Inner quality of diet was improved by extrusion bulking, and the whole digestibility of pellet artificial diet was increased.3. Silkworms rearing with pellet artificial diet have good feeding habit, and therewere no obvious differences on olfaction and feeding habit compared with thoserearing with cooking diet.4. There were significant influences of the water amount of pellet artificial diet and light condition on feeding habit. The range of suitable water amount was 1.6-1.8 times, in this range, feeding habit of silkworm was best. The order of feeding habit is that dark rearing is better than nature illumination rearing, and nature illumination rearing is better than light rearing in the different light conditions.5. There was a remarkable relation between water amount and growth and development. The suitable amount of water was 1.8 times when rearing young silkworm with pellet artificial diet, and it was 1.6 times when rearing growth silkworm. So long as artificial diet absorbed water sufficiency and equality, there was no significant effect of time which absorbed water on growth and development. Considering the disperse of diet and rearing manipulation, the suitable time was about 1 h.6. The growth and development of young silkworm was enhanced with the increasing of rearing times. The suitable feeding amount was 50mg/head in 1-2 instars of young silkworm; the suitable rearing density was 1.5head/cm2; in the definite range, there was no significant relativity between amount of ingestion of unit weight body and feeding amount or rearing density; with feeding amount increasing or rearing density decreasing, digestion of dry food increased, but rate of ingestion decreased.7. There was significant effect of rearing environment on growth and development of silkworm, in which temperature and light were key factors. The best rearing environment was 29℃-30℃, dark rearing. With the instar increasing, the suitable temperature decreased gradually. There was infinite reciprocity between temperature and light.8. There were no significant effect of additive 0.01%-0.2% Vc in pellet artificial diet on feeding habit of silkworm, in the range of additive 0.2%-0.4%Vc, weight of molter body was increased, but exceeding of 0.6%, there was significant restraint on feeding habit; in the view of growth and development, the suitable additive was 0.25%. There was no nee...
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