Partially Defatted <i>Tenebrio molitor</i> Larva Meal in Diets for Grow-Out Rainbow Trout, <i>Oncorhynchus mykiss</i> (Walbaum): Effects on Growth Performance, Diet Digestibility and Metabolic Responses
Giulia Chemello,
Manuela Renna,
Christian Caimi,
Inês Guerreiro,
Aires Oliva-Teles,
Paula Enes,
Ilaria Biasato,
Achille Schiavone,
Francesco Gai,
Laura Gasco
Affiliations
Giulia Chemello
Department of Agricultural, Forest and Food Sciences, University of Turin, Largo P. Braccini 2, 10095 Grugliasco (TO), Italy
Manuela Renna
Department of Veterinary Sciences, University of Turin, Largo P. Braccini 2, 10095 Grugliasco (TO), Italy
Christian Caimi
Department of Agricultural, Forest and Food Sciences, University of Turin, Largo P. Braccini 2, 10095 Grugliasco (TO), Italy
Inês Guerreiro
CIMAR/CIIMAR-Centro Interdisciplinar de Investigação Marinha e Ambiental, Universidade do Porto, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4450-208 Matosinhos, Portugal
Aires Oliva-Teles
CIMAR/CIIMAR-Centro Interdisciplinar de Investigação Marinha e Ambiental, Universidade do Porto, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4450-208 Matosinhos, Portugal
Paula Enes
CIMAR/CIIMAR-Centro Interdisciplinar de Investigação Marinha e Ambiental, Universidade do Porto, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4450-208 Matosinhos, Portugal
Ilaria Biasato
Department of Agricultural, Forest and Food Sciences, University of Turin, Largo P. Braccini 2, 10095 Grugliasco (TO), Italy
Achille Schiavone
Department of Veterinary Sciences, University of Turin, Largo P. Braccini 2, 10095 Grugliasco (TO), Italy
Francesco Gai
Institute of Science of Food Production, National Research Council, Largo P. Braccini 2, 10095 Grugliasco (TO), Italy
Laura Gasco
Department of Agricultural, Forest and Food Sciences, University of Turin, Largo P. Braccini 2, 10095 Grugliasco (TO), Italy
Insect meals are good candidates to replace fishmeal as new protein sources in aquafeeds. This study evaluated the effects of fishmeal replacement with different dietary inclusion levels of a partially defatted Tenebrio molitor (L.) larva meal (TM) on rainbow trout (Oncorhynchus mykiss Walbaum) growth, diet digestibility, and hepatic intermediary metabolism. A 154-day growth trial was performed with 252 rainbow trout (78.3 ± 6.24 g) randomly divided into twelve tanks and fed four experimental diets containing increasing levels of TM: 0% (TM0), 25% (TM25), 50% (TM50), and 100% (TM100) of fishmeal substitution, corresponding to TM dietary inclusion levels of 0%, 5%, 10%, and 20%, respectively. A digestibility trial was performed feeding 180 rainbow trout (94.6 ± 7.31 g) with the experimental diets used in the growth trial. The growth parameters were not affected by TM dietary inclusion. Regarding the evaluated apparent digestibility coefficients (ADC), only the ADC of crude protein was affected, showing the following trend: TM0 = TM25 > TM50 > TM100. The activities of key hepatic amino acid catabolic and lipogenic enzymes were not affected by the dietary composition. The results suggest that a partially defatted TM could totally replace fishmeal in commercial rainbow trout diets without negative effects on fish performance.
