Journal Article

Dietary Inclusion of Tenebrio Molitor Meal in Sea Trout Larvae Rearing: Effects on Fish Growth Performance, Survival, Condition, and GIT and Liver Enzymatic Activity

Nogales-Merida, Silvia, Hoffmann, Lilianna, Rawski, Mateusz, Mazurkiewicz, Jan

2020

Overview

Sea trout ( m. ) is a species for which effective methods of rearing are still being developed. They need high-quality protein in their diet, but, considering the ecological consequences of fishmeal production, new sources of protein are needed. Presently, insect meal is one of the most promising alternative sources of protein in the diets of farm animals. Insect production does not result in excessive gas emissions, waste generation or the risk of obtaining low-quality dietary protein. The study on sea trout larvae was carried out for 60 days. Four diets were given to the fish: one control (C), without the inclusion of insect meal, and three experimental, with one unhydrolysed meal (TM) and two hydrolysed meal treatments. The effects of the diets were evaluated on the basis of growth performance (weight and length of the fish, SR, SGR, RGR, FCR and PER), somatic indices (HSI and VSI) and fish condition (CF). We observed that the highest body mass and weight gain were obtained in the control group. However, the lowest mortality and the highest values of RGR were observed only in groups fed diets containing mealworm meal. The results for the hepato- and viscerosomatic indices showed a lack of statistically significant differences between the control group and the unhydrolysed meal group in terms of the enzymatic activities of amylase, lipase and trypsin in the fish intestine and both aminotransferases in the liver. Our study demonstrated that the inclusion of 20% mealworm meal in practical diets for sea trout did not negatively affect growth performance or gastrointestinal tract (GIT) enzyme activity. The hydrolysed mealworm meal and the non-processed mealworm meal had similar effects.

• Publisher: Sciendo,De Gruyter Brill Sp. z o.o., Paradigm Publishing Services
• Subject: amylases / animal growth / Body mass / body weight / Body weight gain / carboxylic ester hydrolases / Diet / dietary protein / digestive tract / Ecological effects / Enzymatic activity / Enzyme activity / farms / Fish / Fish meal / Gastrointestinal system / Gastrointestinal tract / growth performance / High protein diet / hydrolysed protein / hydrolysis / insect meal / Insects / Intestine / intestines / Larvae / larvae rearing / Lipase / Liver / Low protein diet / mortality / Proteins / risk / Salmo trutta / sea trout / Statistical analysis / Tenebrio molitor / transaminases / Trout / Trypsin / weight gain