Performance, blood and histological parameters and gene expression of lipogenic markers in tilapia (Oreochromis niloticus) fed Tenebrio molitor larvae meal

The objective of the present study was to evaluate different inclusion levels of mealworm (Tenebrio molitor) larvae meal in the diet of Nile tilapia (Oreochromis niloticus). Two hundred male Tilapia juveniles were distributed in a completely randomized design (CRD) with five treatments (0%, 6.5%, 13%, 19.5% and 26% mealworm larvae meal) and four repetitions (polyethylene tanks), with 10 animals each. Productive performance, blood, histological and molecular parameters and viscerosomatic and hepatosomatic indices were evaluated. Among the evaluated parameters, final biomass, biomass gain, final weight, weight gain and apparent feed consumption were influenced by the inclusion of mealworm larvae meal in the feeds; the best results were obtained with an inclusion level of 26%. The tilapia fed with mealworm larvae meal showed higher body and fillet weights and larger muscle fibres. In addition, they presented similar values of biochemical components compared to animals fed the standard diet. Lipogenic genes were significantly higher expressed in groups fed mealworm larvae meal. In view of the findings, the inclusion of mealworm larvae meal in the diet of Nile tilapia is a viable approach, and inclusion levels of up to 26% of replacement of digestible protein have no negative impacts on the analysed parameters.