家蚕少回育对全茧量和茧层率的影响

目的]探讨一日一回育和一日二回育2种少回育方式以及少回育下蚕头密度和5龄给桑量对全茧量和茧层率的影响,分析家蚕少回育省力化养蚕的可行性.方法]分别调查了不同蚕头密度、5龄给桑量、日给桑频次条件下的全茧量和茧层率.结果]在一日二回给桑片叶育条件下,蚕头密度为630～880头/m2时各给桑量的全茧量和茧层率均无显著差异,但蚕头密度为1 100 头/m2时的全茧量和茧层率显著低于其他蚕头密度.在适度蚕头密度条件下,除75％给桑量的全茧量显著低于其他给桑量外,各给桑量的全茧量和茧层率均无显著差异,但全茧量、茧层率均与给桑量呈正相关；当蚕头密度过大时,全茧量、茧层率与给桑量呈负相关.一日一回育的全茧量极显著低于一日二回育,但2种少回育方式在茧层率上的差异不显著.结论]在片叶育方式下,一日二回育优于一日一回育,一日二回育中5龄给桑量和蚕头密度分别以85％的给桑量和880头/m2的蚕头密度为最佳.

The Influence of Less Feeding a Day of Silkworm to the Whole Cocoon Weight and the Cocoon Shell Rate

Objective] To analyze the feasibility of the less feeding a day for laborsaving-rear by studying the influence from one feeding a day,two feeding a day,the rearing density and the amount of mulberry leaves for the fifth instar to the whole cocoon weight and the cocoon shell rate.Method] The whole cocoon weight and the cocoon shell rate were investigated under the condition of different the rearing density,the amount of mulberry leaves for the fifth instar and the feeding frequency a day respectively.Result] The results showed that under two leaf feeding a day,the whole cocoon weight and the cocoon shell rate between each amount of supplied leaves have a significant difference when the rearing densities were between 630 head/m2 to 880 head/m2,but the whole cocoon weight and the cocoon shell rate under the rearing density at 1100 head/m2were significantly lower than that of other rearing densities.In the conditions of the moderate rearing densities,besides the whole cocoon weight of 75% amount of supplied leaves was significantly lower than that of other amount of supplied leaves,the whole cocoon weight and the cocoon shell percentage between each amount of supplied leaves were not significant differences,but the whole cocoon weight and the cocoon shell rate were positively correlated with the amount of supplied leaves.When the rearing densities were too large,the whole cocoon weight and the cocoon shell rate would be negatively correlated with the amount of supplied leaves.The results also showed that the whole cocoon weight of one feeding a day was very significant less than that of two feeding a day,but the rate of cocoon shell of two kinds of less feeding was not significant.Conclusion] Comprehensive analysis showed that in the condition of leaves feeding,the rearing effect of two feeding a day was better than that of one feeding a day,and the best amount of supplied mulberry leaves for the fifth instar and rearing density were 85% and 880 head/m2 in two feeding a day respectively.