Tenebrio molitor and Zophobas morio Full-Fat Meals in Broiler Chicken Diets: Effects on Nutrients Digestibility, Digestive Enzyme Activities, and Cecal Microbiome
Department of Animal Nutrition, Poznań University of Life Sciences, Wołyńska 33, 60-637 Poznań, Poland
HiProMine S.A., Poznańska 8, 62-023 Robakowo, Poland
Division of Inland Fisheries and Aquaculture, Institute of Zoology, Poznań University of Life Sciences, Wojska Polskiego 71c, 60-625 Poznań, Poland
Department of Preclinical Sciences and Infectious Diseases, Poznań University of Life Sciences, Wołyńska 35, 60-637 Poznań, Poland
Department of Poultry Science, Faculty of Animal Bioengineering, University of Warmia and Mazury in Olsztyn, Oczapowskiego 5, 10-719 Olsztyn, Poland
Author to whom correspondence should be addressed.
Animals 2019, 9(12), 1128; https://doi.org/10.3390/ani9121128
Received: 7 November 2019 / Revised: 5 December 2019 / Accepted: 7 December 2019 / Published: 12 December 2019
(This article belongs to the Collection Insects as Animal Feed: a New Promising Sector)
In animal nutrition, the links among health status, alimentary tract factors and gastrointestinal tract (GIT) integrity are increasing in importance. It has been documented that insects are useful as novel ingredients in poultry diets because they contain bioactive compounds such as chitin, melanin, and antimicrobial peptides, in addition to protein and dietary fat, and these bioactive compounds have been reported to modulate the GIT microbiome. From this perspective, insects could be promising functional feed additives to stimulate GIT health through inhibition of potentially pathogenic bacteria. Therefore, we evaluated the effect of the addition of a small amount of insects to the broiler chicken diet on the GIT microbiota composition and activity. Six experimental groups were used in the current study, i.e., two different levels (0.2% and 0.3%) of yellow mealworm and super mealworm full-fat meals, a positive control with salinomycin addition, and a negative control without any additives. Insect full-fat meals were capable of improving the health status of the birds by a positive reduction in potentially pathogenic bacteria in the cecal digesta and stimulation of the GIT microbiome to produce enzymes, especially glycolytic enzymes.
This study was conducted to investigate the effect of insect full-fat meals added in relatively small amounts to a complete diet on the coefficients of apparent ileal digestibility, short-chain fatty acid (SCFA) concentrations, bacterial enzymes, and the microbiota community in the cecal digesta of broiler chickens. In total, 600 one-day-old female Ross 308 broiler chicks were randomly assigned to six dietary treatments with 10 replicate pens/treatment and 10 birds/pen. The groups consisted of a negative control (NC) with no additives; a positive control (PC; salinomycin 60 ppm), and supplementation with 0.2% or 0.3% Tenebrio molitor or Zophobas morio full-fat meals. Z. morio (0.2%) addition increased the activities of α- and β-glucosidase and α-galactosidase. Dietary insects significantly decreased the cecal counts of the Bacteroides–Prevotella cluster in comparison to those in the NC and PC. Whereas, Clostridium perfringens counts were increased in the broiler chickens subjected to the 0.3% Z. morio treatment. In conclusion, small amounts of full-fat insect meals added to broiler diets were capable of reducing the abundance of potentially pathogenic bacteria, such as the Bacteroides–Prevotella cluster and Clostridium perfringens. In addition, this supplementation was able to stimulate the GIT microbiome to produce enzymes, especially glycolytic enzymes.