Exploring rumen fermentation and microbial populations in Dhofari goats fed a chitosan-added diet

Abstract

The use of chitosan (CHI) in ruminant diets is a promising natural modifier for rumen fermentation, capable of modulating both the rumen pattern and microbial activities. The objective of this study was to explore the rumen fermentation and microbial populations in Dhofari goats fed a diet supplemented with CHI. A total of 24 Dhofari lactating goats (body weight, 27.32 ± 1.80 kg) were assigned randomly into three experimental groups (n = 8 ewes/group). Goats were fed a basal diet with either 0 (control), 180 (low), or 360 (high) mg CHI/kg of dietary dry matter (DM) for 45 days. Feeding high CHI linearly increased (p < 0.05) the propionate level and reduced the acetate, butyrate, and total protozoa count (p < 0.05). Ruminal ammonia nitrogen (NH₃–N) concentrations and the acetate:propionate ratio decreased linearly when goats were fed CHI (p < 0.05). The abundances of both Spirochetes and Fibrobacteres phyla were reduced (p < 0.05) with both CHI doses relative to the control. Both low and high CHI reduced (p < 0.05) the relative abundances of Butyrivibrio hungatei, Fibrobacter succinogenes, Ruminococcus albus, Ruminococcus flavefaciens, Selenomonas ruminantium and Neocallimastix californiae populations. Adding CHI significantly decreased (p < 0.05) the abundances of Ascomycota, Basidiomycota, and Bacillariophyta phyla compared to the control. Adding CHI to the diet reduces the abundance of fibrolytic-degrading bacteria, however, it increases the amylolytic-degrading bacteria. Application of 360 mg of CHI/kg DM modified the relative populations of ruminal microbes, which could enhance the rumen fermentation patterns in Dhofari goats.

Keywords:

• Chitosan additive
• rumen fermentation
• microbiome sequencing
• Dhofari goats

Acknowledgments

The authors acknowledge the Livestock research station and Feed analytical laboratory staff for their technical assistance during the experiment, sampling collection, and analyses.

Authors contribution

Hani M. El-Zaiat: project administration, investigation, funding acquisition, conceptualization, supervision and editing, methodology, writing-original draft, validation-review, and editing. Waleed Al-Marzooqi: data curation, writing-editing and review, resources, validation, methodology, investigation. Kaadhia Al-Kharousi: sample collections, formal analysis, methodology, and validation.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This study was funded by Sultan Qaboos University, Project No. IG/AGR/ANVS/21/01.