Nadia Sarkar Effect of Formulated Artificial Diets on Growth Performance and Silk Production in the Silkworm (Bombyx mori L.)

Abstract

Nutrition is a critical determinant of growth and silk productivity in the silkworm (Bombyx mori L.), yet reliance on mulberry leaves creates seasonal constraints, particularly in Bangladesh. This study assessed the effects of two formulated artificial diets, based on mulberry leaf powder, soy flour, and corn flour, compared with mulberry-fed controls in the BN/M multivoltine race. Key growth, cocoon, pupal, and silk fibre traits were measured, and multivariate analyses (PCA, correlation, and clustering) were applied to reveal the interrelationships among these traits. Results showed that mulberry leaves ensured superior larval growth and silk gland development, but artificial diets provided trait-specific benefits. Diet 1 enhanced the shell ratio (14.57%) and fibre length (401 m), while Diet 2 yielded heavier male (0.869 g) and female pupae (1.268 g). PCA separated growth/biomass traits from silk productivity traits, highlighting trade-offs between larval development and fibre yield. Strong correlations, such as between fifth-instar weight and silk fibre output, confirmed the biological linkage between nutrient intake and cocoon productivity. Clustering further distinguished artificial diet treatments from mulberry-fed controls, indicating distinct phenotypic responses. This is the first systematic evaluation of artificial diets for the BN/M race under Bangladeshi sericulture conditions. The findings demonstrate that while mulberry leaves remain indispensable, artificial diets can supplement rearing during lean seasons by enhancing specific economic traits. A cost analysis revealed that although artificial diets are slightly more expensive, they help offset seasonal shortages and sustain cocoon yields, thereby supporting sericulture resilience in regions with limited mulberry availability.

J. Bio-Sci. 34(1): 74-87, 2026