Impact of the Diet on the Mortality and on Gene Expression of the Antimicrobial Peptide Tenecin 3 in Tenebrio molitor Larvae Infected by Beauveria bassiana

• Published in: Insects (Basel, Switzerland) Switzerland), 2023-04, Vol.14 (4), p.359
• Main Authors: Candian, Valentina, Tedeschi, Rosemarie
• Format: Article
• Language: English
• Subjects: Agribusiness; Agricultural economics; Agricultural production; Antibiotics; Antifungal activity; Antiinfectives and antibacterials; Antimicrobial peptides; Bacteria; Beauveria bassiana; brewers’ spent grain; Diet; Dietary fiber; Economic impact; Entomopathogenic fungi; entomopathogenic fungus; Food; Fungicides; Gene expression; Grain; Immune response; immune responses; Immune system; Insects; Larvae; Microorganisms; Mortality; Nutrition research; Pathogens; Population density; Proteins; Substrates; Survival; Tenebrio molitor; Wheat; Wheat bran
• ISSN: 2075-4450; 2075-4450
• DOI: 10.3390/insects14040359

Large-scale insect rearing can be subjected to microbial infections, leading to serious economic losses. When possible, the use of antibiotics is to be avoided for insects intended as feed or food and new strategies to preserve the health of the farmed insects are required. The effectiveness of insect immune system depends on several factors, including the nutritional composition of the diet. The possibility to modulate immune responses through the diet is currently a topic of great interest from an application point of view. We evaluated the effect of two different diets on the survival rate and gene expression of the antimicrobial peptide Tenecin 3 in uninfected and -infected L. larvae. A wheat bran diet, mixed 50% with brewers' spent grains, could positively influence the expression of Tenecin 3 gene when uninfected is allowed to develop on such a substrate from early larval stages. Even if, in our trial, the diet with added brewers' spent grains could not reduce the mortality of the larvae infected with , higher transcriptional levels of the antifungal peptide were observed in insects fed this diet, depending on the timing of diet administration.