Effects of Yellow Mealworm (Tenebrio molitor) on Growth Performance, Hepatic Health and Digestibility in Juvenile Largemouth Bass (Micropterus salmoides)

Abstract

This study investigated the effects of yellow mealworm meal (TM) on growth performance, hepatic health and digestibility in juvenile largemouth bass (Micropterus salmoides). The fish were fed with the basic feed and the test feed (70% basic feed and 30% raw materials) containing Cr2O3, and feces were collected for digestibility determination. The fish were fed with five isonitrogenous (47% crude protein) and isolipidic (13% crude lipid) diets, in which fishmeal (FM) was replaced with 0% (TM0), 12% (TM12), 24% (TM24), 36% (TM36) and 48% (TM48) TM. The fish were reared in cylindrical plastic tanks in a recirculating aquaculture system for 11 weeks. The apparent digestibility coefficients (ADC), of dry matter, crude protein and crude lipid, in largemouth bass of TM were 74.66%, 91.03% and 90.91%, respectively. The ADC of total amino acid (TAA) of TM in largemouth bass was 92.89%, and the ADC of essential amino acid (EAA) in TM in largemouth bass was 93.86%. The final body weight (FBW), weight gain rate (WGR) and specific growth rate (SGR) in the TM24 group were significantly higher than those in other groups. Similarly, the highest mRNA expression levels of hepatic protein metabolism genes (pi3k, mtor, 4ebp2 and got) and antioxidant enzyme (glutathione peroxidase, Gpx; catalase, Cat) activities were observed in the TM24 group. Moreover, the expression levels of anti-inflammatory factors (il-10 and tgf) in liver were up-regulated and the expression levels of pro-inflammatory factors (il-8 and il-1β) in liver were down-regulated. Quadratic regression model analysis, based on weight gain rate (WGR) against dietary TM level, indicated that the optimum level of dietary TM replacing FM in largemouth bass diet was 19.52%. Appropriate replacement levels (less than 36%) of FM by TM in the diets can enhance the antioxidant capacity and immunity of largemouth bass. However, high levels of FM substitution with TM (more than 48%) in the feeds can damage the liver health and inhibit the growth of largemouth bass. Notably, largemouth bass has high ADC and high utilization of TM, which indicates that it is feasible to use TM as feed protein source for largemouth bass.

Biodegradation of polystyrene nanoplastics by Achromobacter xylosoxidans M9 offers a mealworm gut-derived solution for plastic pollution

“…Approximately 50 mealworms were placed in a polypropylene (PP) box with a capacity of 200 mL. The mealworms were then placed in incubators that were kept at a temperature of 25 °C and a humidity level of 70% (Yang et al 2021b ; Bulak et al 2021 ; Chen et al 2023 ; Cheng et al 2023 ). The mealworms were divided into four experimental groups Fig.…”

“…Extensive studies have shed light on the remarkable ability of Tenebrio molitor larvae and other invertebrates to consume and degrade plastic materials efficiently. These organisms demonstrate a unique capacity to break down various polymers, effectively metabolizing the resulting substances (Yang et al 2015a , b , 2020 ; Urbanek et al 2020 ; Yang et al 2021a ; Bulak et al 2021 ). Identifying specific bacteria in the gut microbiomes of these invertebrates has proven vital in this process.…”

Enzymatically Hydrolyzed Poultry By-Product Supplementation, Instead of Fishmeal, Alone Improves the Quality of Largemouth Bass (Micropterus salmoides) Back Muscle without Compromising Growth

“…Fishmeal is a crucial component of largemouth bass farming, accounting for a significant portion of the feed costs [ 25 ]. Several studies have investigated alternative feed options for largemouth bass [ 26 , 27 , 28 ]. Furthermore, there is a growing concern regarding the muscle quality of largemouth bass [ 29 , 30 ].…”