Effect of Disinfection Practices on Survival and Productivity of Silkworm (Bombyx mori)

Abstract

Disinfection is an essential component of hygienic silkworm rearing because microbial contamination can reduce larval survival and cocoon productivity. This study evaluated five disinfection practices for Bombyx mori under a completely randomized design with four replications and 100 larvae per replication. The treatments comprised an untreated control, rearing-room disinfection with 2% formalin, bed disinfection with slaked lime, combined 2% formalin and slaked lime and the commercial bed disinfectant Vijetha. Larval survival, disease incidence, single cocoon weight, shell weight, and shell ratio were recorded and analyzed using analysis of variance, and treatment means were separated by Tukey’s test at the 5% significance level. All measured parameters differed significantly among treatments (p < 0.05). The combined formalin and slaked lime treatment produced the highest larval survival (94.10 ± 0.44%) and the lowest disease incidence (5.90 ± 0.09%), whereas the untreated control recorded the lowest survival (81.50 ± 0.91%) and the highest disease incidence (18.50 ± 0.18%). The combined treatment also recorded the greatest single cocoon weight (2.05 ± 0.29 g), shell weight (0.46 ± 0.004 g) and shell ratio (22.44 ± 0.31%). Vijetha improved performance relative to the control but was less effective than the combined treatment. These findings indicate that integrating rearing-room disinfection with bed sanitation can reduce disease pressure and improve cocoon traits under controlled rearing conditions. Formalin should be applied according to recommended procedures with appropriate protective measures and ventilation.