Effects of artificial diet rearing during all instars on silk secretion and gene transcription in Bombyx mori (Lepidoptera: Bombycidae)

Abstract

Silkworms (Bombyx mori) reared on artificial diets during all instars have the advantages of simplicity and efficiency, year-round production, and reduced risk of poisoning. However, low silk yield remains a challenge, limiting its industrial application. To address this issue, the spinning behavior, nutrient absorption, and transcriptomics of silkworms were investigated. Compared with silkworms reared on mulberry leaves during all instars, those fed with artificial diets showed significantly lower cocoon weight, cocoon shell weight, cocoon shell rate, and silk gland tissue somatic index at the end of the fifth instar (P < 0.01). The spinning duration and crawling distance of silkworms reared on artificial diets were also significantly lower than those reared on mulberry leaves (P < 0.01). Regarding nutrient absorption, the dietary efficiency indexes of silkworms fed with artificial diets were significantly lower than those fed with mulberry leaves, except for the efficiency conversion of digesta to cocoon (P < 0.01). Further RNA-Seq analysis revealed 386 differentially transcribed genes between the 2 groups, with 242 upregulated and 144 downregulated genes. GO enrichment analysis showed that differential transcriptional genes were mainly enriched in organic acid metabolism, oxidation–reduction, and drug catabolism. KEGG enrichment analysis showed that differential transcriptional genes were mainly enriched in genetic information processing and metabolism pathways. Our findings provide new insights into the silk secretion and can serve as a reference for future research and application of silkworms fed with artificial diets.

Novel insights into the economic relevant phenotypes ofBombyx moristrains from Romanian breeding centres

“…The biological and economic parameters of the B. mori larvae and adults that were fed with an artificial diet were assessed in the November-December period. Yin et al (2023) argued that feeding the silkworms with an artificial diet negatively impacts some of their traits, therefore affecting their economic value. Even by supplementing the artificial diet with bee pollen, the measured parameters were not significantly improved (Moise et al, 2020).…”

An In-Depth Insight into the Profile, Mechanisms, Functions, and Transfer of Essential Amino Acids from Mulberry Leaves to Silkworm Bombyx mori L. Pupae and Fish

“…One of the consequences is that artificial diets have been proposed as suitable alternatives. Even though the artificial diet has gained greater acceptance in recent years, studies have revealed that the development of silkworms has been affected [106]. It has been shown that mulberry leaves have a higher nutritional content than any artificial diet [40].…”

Effects of Habitual Dietary Change on the Gut Microbiota and Health of Silkworms

“…In order to improve production efficiency, modern sericulture has gradually started using artificial diets (ADs) as a substitute for MLs in silkworm rearing [15]. However, silkworms fed on ADs exhibit significantly diminished robustness and silk production efficiency [16,17]. Studies using mice and other models have revealed that a high-fat diet (HFD) or high-sugar diet (HSD) significantly affects the composition and function of the gut microbiota, thus impairing the host's metabolic homeostasis [18,19].…”