Effect of dietary supplementation with chitooligosaccharides on wound healing in dogs

Abstract

Abstract Background Wound healing has long been a subject of great interest for pathologists. Previous research has established the effectiveness of topical application of chitooligosaccharides (COSs) on wound healing. However, studies on their potential usefulness as food additives to improve wound healing are lacking. Objective Here, we investigated whether dietary supplementation with COSs could promote wound healing using Beagle dogs as an animal model. Methods Nine dogs were evenly assigned randomly into control, 0.5% COSs and 1% COSs groups. Control dogs were fed with a non‐supplemented dietary formula (vehicle). Dogs in 0.5% COSs and 1% COSs groups were fed with a dietary formula supplemented with 0.5% and 1% COSs. After 8 weeks of feeding, dogs in each group underwent surgery with three matching full‐thickness 2 × 2‐cm skin defects were created with a scalpel on the left side of the dorsal midline, 2 cm apart from each other. Wounds were photographed and the healing percentage was determined on day 0, 2, 4, 7, 9, 11, 14, 16, 18 and 21. The healing process was assessed by daily gross examination, histologic examination and Masson's trichrome staining on days 7, 14 and 21. Considering the important role of the transforming growth factor‐β (TGF‐β1) signalling pathway in wound healing, immunostaining was used to evaluate TGF‐β1 expression. Results The results showed that wound healing was accelerated; collagen synthesis and TGF‐β1 expression were enhanced in response to dietary supplementation with COSs. Conclusions This study makes an original contribution to the understanding of wound healing in dogs and other animals and supports the use of COSs as a supplement to be added to animal diets.

Keywords

• chitooligosaccharides
• dog food
• TGF‐β
• wound healing