Characterisation of the intestinal microbiota of commercially farmed saltwater crocodiles, Crocodylus porosus
The Australian saltwater crocodile (Crocodylus porosus) industry began commercially in the 1980s, producing skins for export and crocodile meat as a by-product. Industry research has thus far focused on strategies to improve production efficiency. In the current study, we utilised 16S rRNA sequencing to characterise the intestinal microbiome of Australian saltwater crocodiles. Samples were collected from 13 commercially farmed crocodiles from six sample sites along the length of the intestinal tract. The results indicate a similar microbiome composition to that found in the freshwater alligator, with the dominate phyla represented by Firmicutes, primarily Clostridia, and Fusobacteria, which appears to be distinct from mammalian, fish, and other reptile phyla which are generally dominated by Firmicutes and Bacteroidetes. The high abundance of ‘pathogenic’ bacteria, with no apparent consequence to the host’s health, is of great interest and warrants further additional investigation. This will enable expansion of the current understanding of host immune function and how it is modified by host and intestinal microbiome interactions.
Keywords: Saltwater crocodile Crocodylus porosus Microbiota Gastrointestinal tract
The authors would like to thank the staff at the Koorana Crocodile Farm and Joshua McIntyre for assistance with sample collection.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no competing interests.
The sample collection was approved by the Central Queensland University Animal Ethics Committee, Project Number: / 0000020311
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