不同酵化时间和饲养密度对双叉犀金龟幼虫转化菌糠的影响

Effects of different fermentation duration and feeding densities on the conversion of mushroom bran by Allomyrina dichotoma larvae

【目的】利用双叉犀金龟Allomyrina dichotoma生物治理菌糠,既可实现菌糠废弃物的无害化处理与应用,又可有效降低昆虫的饲养成本。本研究旨在明确菌糠发酵程度和种群饲养密度对双叉犀金龟幼虫转化菌糠的影响,为利用双叉犀金龟生物治理菌糠提供理论支撑。【方法】在29℃条件下,调查3龄幼虫连续40 d对不同酵化时间(10、20、30和40 d)和不同饲养密度(20、30、40、50和60头/箱)条件下的取食菌糠量、排粪量和虫体增重等指标。【结果】随着菌糠酵化时间的延长,双叉犀金龟转化菌糠能力呈显著上升趋势,发酵40d时,双叉犀金龟连续40d的取食量为(42.11±0.14)g/头、排粪量(30.12±0.40)g/头、虫体增重量(8.21±0.26)g/头,显著高于其他处理,但与对照无显著差异(P<0.05);随着密度增加,虫体存活率无显著差异(P>0.05),但平均虫体增重量、取食量、排粪量均呈显著下降的趋势,其中密度30头/箱处理平均虫体增重量为(5.20±0.06)g/头,平均取食量为(56.32±1.14)g/头,排粪量为(35.74±0.47)g/头,与最小密度20头/箱处理无显著差异,但显著高于其他密度处理(P<0.05)。【结论】双叉犀金龟3龄幼虫对酵化时间为40 d的木耳菌糠转化能力最强,种群密度应不高于30头/箱。

[Aim]Feeding fermented mushroom bran to Allomyrina dichotoma larvae not only enables harmless treatment and efficient utilization of mushroom bran waste,it also effectively reduces insect rearing costs.This study aimed to determine how fermentation duration and population rearing density affect the conversion of mushroom bran by A.dichotoma larvae,providing theoretical support for biological control and utilization of mushroom bran by the beetle larvae.[Methods]3rd instar larvae were raised at 29℃for 40 days.The amount of mushroom bran consumed,feces excreted,and larval weight,were measured under different fermentation durations(10,20,30 and 40 d,respectively)and different rearing densities(20,30,40,50,60 larvae/case,respectively).[Results]There was a significant increase in the ability of larvae to transform mushroom bran with increasing fermentation time.Food intake,the amount of feces excreted,and larval weight was(42.11±0.14),(30.12±0.40)and(8.21±0.26)g,respectively,in A.dichotoma fed mushroom bran fermented for 40 days.This result was significantly higher compared to the other treatment groups but not the control(P<0.05).There was no significant difference in the survival rate of the larva with increasing rearing density(P>0.05),but average weight gain,food intake,and feces excretion showed a significant downward trend.At a density of 30 larvae/case,average larval weight gain,food intake,and feces excretion was(5.20±0.06),(56.32±1.14)and(35.74±0.47)g,respectively.This result was not significantly different from the minimum density of 20 larvae/case,but it was significantly higher than the other density treatments(P<0.05).[Conclusion]Based on our findings,the optimal fermentation time for the effective conversion of mushroom bran by A.dichotoma,is 40 days.To conserve resources,the population density of A.dichotoma should not exceed 30 larvae/case.