Dried fruit pomace inclusion in poultry diet: growth performance, intestinal morphology and physiology

Elena Colombino; Ilario Ferrocino; Ilaria Biasato; Luca Simone Cocolin; Daniel Prieto-Botella; Zenon Zduńczyk; Jan Jankowski; Joanna Milala; Monika Kosmala; Bartosz Fotschki; Maria Teresa Capucchio; Jerzy Juśkiewicz

doi:10.1186/s40104-020-00464-z

Dried fruit pomace inclusion in poultry diet: growth performance, intestinal morphology and physiology

J Anim Sci Biotechnol. 2020 Jun 19:11:63. doi: 10.1186/s40104-020-00464-z. eCollection 2020.

Affiliations

¹ Department of Veterinary Sciences, University of Torino, Largo Paolo Braccini 2, Grugliasco, 10095 Turin, Italy.
² Department of Agricultural, Forest and Food Sciences, University of Torino, Torino, Italy.
³ Research Team on Occupational Therapy (InTeO), Department of Surgery and Pathology, University Miguel Hernandez of Elche, Alicante, Spain.
⁴ Polish Academy of Sciences, Institute of Animal Reproduction and Food Research, Olsztyn, Poland.
⁵ Department of Poultry Science, University of Warmia and Mazury, Olsztyn, Poland.
⁶ Institute of Chemical Technology of Food, Lodz University of Technology, Lodz, Poland.

Abstract

Background: Fruit pomaces are by-products rich in polyphenol compounds and dietary fiber. They seem to play an important role in regulating the gut microbiota, morphology and physiology. The aim of this study was to assess whether apple (A), blackurrant (B) or strawberry (S) pomaces could be suitable ingredients in broiler diets and their effect on gut health. A total of 480 male broilers were randomly allotted to 8 dietary treatments with lower (3%-L) or higher (6%-H) dietary fiber content: two control groups (CL/CH), two A diets (AL/AH), two B diets (BL/BH), two S diets (SL/SH). Diet and fruit pomaces were chemically analyzed to assess polyphenol concentration and fibre fraction content. After the evaluation of growth performance, 6 birds/group were slaughtered at 35 days of age. Morphometric and histopathological investigations were performed on duodenum, jejunum and ileum. Excreta were collected to perform microbiota evaluation by 16S DNA sequencing. Weight, viscosity, enzymatic activity, short chain fatty acid (SCFAs) and ammonia concentration were determined in ileum and/or ceca content.

Results: A pomace and A diets showed the lowest polyphenol content and the highest content of soluble fibre fraction. No significant differences were observed for growth performance, gut morphometry and histopathology (P > 0.05). Dietary fruit pomace inclusion increased the weight of ileum and ceca and the ileum digesta viscosity (P < 0.05). In the ileum, A and S groups showed lower bacterial α-glucosidase activity than C groups. Moreover, small intestine SCFAs concentration was higher in fruit pomaces diets (P < 0.05). In ceca, B and S groups showed lower ammonia concentration and higher SCFAs than C. Dietary treatments also influenced the activity of α-glucosidase, α-galactosidase, β-galactosidase β-glucuronidase and xylase. Regarding microbiota, at phylum level, Firmicutes were differentially abundant across treatment (maximum for C and minimum in S, FDR > 0.05). At genus level, an increase of Weissella in AH and Erwinia in S/B diets, as well as a decrease of Lactobacillus in all fruit pomace groups were recorded (P < 0.05).

Conclusions: Fruit pomaces could be suitable ingredients in poultry nutrition even if further studies are needed to better understand which doses is more recommended to avoid negative effects on gut microbiota.

Keywords: Fruit Pomace; Gut health; Morphohistology; Polyphenols; Poultry.