Tenebrio molitor Larvae Meal Affects the Cecal Microbiota of Growing Pigs

Abstract

<jats:p>The hypothesis tested was that dietary inclusion of insect meal (IM) causes an alteration in the cecal microbiota composition and its fermentation activity of growing pigs. Five-week-old male crossbred pigs were randomly assigned to three groups of 10 pigs each, and fed isonitrogenous diets either without (CON) or with 5% IM (IM5) or 10% IM (IM10) from Tenebrio molitor larvae for four weeks. The relative abundance of the phylum Bacteroidetes was lower in group IM10 than in group CON (p &lt; 0.05), whereas the relative abundance of Firmicutes and the Firmicutes:Bacteroidetes-ratio tended to be higher in groups IM10 and IM5 than in group CON (p &lt; 0.1). The relative abundance of the Proteobacteria tended to be higher in group IM10 than in groups CON and IM5 (p &lt; 0.1). The concentrations of the total short-chain fatty acids in the cecal digesta did not differ between the three groups, but the concentrations of the branched-chain fatty acids in the cecal digesta were higher in group IM5 and IM10 than in group CON (p &lt; 0.05). The present study shows for the first time that the replacement of soybean meal by Tenebrio molitor larvae meal causes a shift of the cecal microbial community and its fermentation activity in growing pigs.</jats:p>

Apparent Digestibility Coefficients of Black Soldier Fly (Hermetia illucens), Yellow Mealworm (Tenebrio molitor), and Blue Bottle Fly (Calliphora vicina) Insects for Juvenile African Catfish Hybrids (Clarias gariepinus × Heterobranchus longifilis)

“…The role of chitin in feed digestion may be influenced by several factors, considering that chitin has an immunostimulatory effect to the intestine [ 13 , 70 ] and chitin was also shown to stimulate bile acid excretion resulting in an increased fecal loss of bile acids [ 71 ]. Compared to BSL, MW presents a more complex chitin-protein matrix [ 44 ] and lower trypsin susceptibility [ 72 ].…”

Feeding of cuticles from Tenebrio molitor larvae modulates the gut microbiota and attenuates hepatic steatosis in obese Zucker rats

“…Further processing of raw sequences was carried out as described recently. 10 Finally, sequences with a relative abundance > 0.5% in at least one sample were sorted, merged and operational taxonomic units (OTU) were picked at a threshold of 97% similarity. Taxonomic classification to the OTU was assigned using the RDP classifier.…”

“…Most of these studies revealed that larvae meal from TM and HI is a suitable protein source in practical feeding rations for broiler and pigs which can replace conventional protein sources, such as soybean protein, without impairing animal performance or causing adverse effects. 3–11 Apart from this, few studies dealing with the potential of the isolated fat from TM and HI larvae in broiler demonstrated that insect biomass is also a suitable source of fat which can replace other fat sources in feeding rations for monogastric farm animals. 12,13 In addition, recent studies demonstrated that larvae meal from TM has strong lipid-lowering effects in the obese Zucker rat, 14–16 a rodent model of obesity, steatosis, dyslipidemia and metabolic syndrome, indicating that insect larvae meal might be also used as a bioactive, health-promoting food being of particular interest for humans suffering from obesity-associated metabolic disorders.…”

Feeding of Hermetia illucens Larvae Meal Attenuates Hepatic Lipid Synthesis and Fatty Liver Development in Obese Zucker Rats

“…Although we did not analyze the gut microbiota structure of the rats, it is not unlikely that feeding of the HI larvae meal-diets has also modified the gut microbiota composition of the obese rats in a beneficial manner, thereby contributing to the strong antisteatotic effects observed. In line with this, several studies with broilers and pigs have demonstrated that feeding of different insect larvae meals affects the gut microbiota composition [ 12 , 48 , 49 ]. However, in order to clarify this speculative issue, future studies have to demonstrate that HI larvae meal alters the gut microbiota composition in a favorable manner in the obese Zucker rat.…”

“…Although the bioactive compounds responsible for the inhibitory effect of TM larvae meal on lipogenesis remain to be identified, different constituents of TM larvae meal may be likely candidates for its lipid-lowering action. One is chitin, an intrinsic constituent of the insect’s exoskeleton, which makes up 9–13% of dry matter in TM larvae meal [ 8 , 12 ], and has been demonstrated to cause lipid-lowering effects [ 13 ]. Other possible candidates are biologically active peptide sequences, which have been found in different dietary proteins including milk protein [ 14 ], egg protein [ 15 ], soybean protein [ 16 , 17 ] and peanut protein [ 18 ].…”