41-Title: Comparative metagenomic analysis of samples from footrot-affected sheep and healthy sheep
Authors: Apurva Gupta, Anil Taku, MA Bhat, Indica Sharma, Deep Shikha, Ufaq Aijaz, GA Badroo and Faizan Javid
Source: Ruminant Science (2022)-11(1):203-208.
How to cite this manuscript: Gupta Apurva, Taku Anil, Bhat MA, Sharma Indica, Shikha Deep, Aijaz Ufaq, Badroo GA and Javid Faizan (2022). Comparative metagenomic analysis of samples from footrot-affected sheep and healthy sheep. Ruminant Science 11(1):203-208.
Abstract
The present study aimed to analyse the metagenome associated with ovine footrot based on 16S rRNA gene by next-generation sequencing methodology. Two samples were collected, one from footrot-affected sheep and one from healthy sheep and both were compared for their associated microbial diversity. Footrot was detected in the affected sample by 16S rRNA gene-based PCR for D. nodosus which showed an amplicon size of 783 bp. Metagenomic analysis of the samples was done using Oxford Nanopore Technology GridION done by Biokart India Pvt. Ltd.(Bangalore) and obtained reads were clustered into Operational Taxonomic Units (OTU’s). The top ten genera found in footrot-affected sheep were Treponema (27%), Acinetobacter (26%), Brevundimonas (17%), Staphylococcus (13%), Candidatus (6%), Agrobacterium (4%), Mycoplasma (2%), Corynebacterium (2%) Ralstonia (2%) and Megasphaera (1%). In the healthy sheep, the top ten genera were Stenotrophomonas (27%), Achromobacter (24%), Brevundimonas (19%), Staphylococcus (14%), Comomonas (5%), Candidatus (3%), Ralstonia (3%), Agrobacterium (2%), Megasphaera (2%) and Rhizobium (1%). Although Brevundimonas and Staphylococcus were also abundant in apparently healthy sheep samples, we envisage that extrinsic and intrinsic factors might affect their niche, producing an imbalance in the bacterial community from healthy to diseased feet. Dichelobacter nodosus, which is the main causative agent of the disease was among the top ten enriched organisms in the footrot-affected sheep sample and was completely absent from apparently healthy sheep. Thus, footrot can be considered a polymicrobial disease as several taxa other than Dichelobacter nodosus are linked to footrot lesions in sheep. To the best of our knowledge, this is the first such study from India.
References
Billington SJ, Johnston JL and Rood JI (1996). Virulence regions and virulence factors of the ovine footrot pathogen, Dichelobacter nodosus. FEMS Microbiology Letter 145:147-156.
Collighan RJ, Naylor RD, Martin PK, Cooley BA, Buller N and Woodward MJ (2000). A spirochete isolated from a case of severe virulent ovine foot disease is closely related to a Treponeme isolated from human periodontitis and bovine digital dermatitis. Veterinary Microbiology 74:249-257.
Devi Sarita, Padhiyar AP, Saxsena Anshul and Jadhav KM (2017). Therapeutic management of foot rot in caprines. Ruminant Science 6(2):389-390.
Dhawi A, Hart CA, Demirkan I, Davies IH and Carter SD (2005). Bovine digital dermatitis and severe virulent ovine foot rot: A common spirochaetal pathogenesis. Veterinary Journal 169:232-241.
Egerton JR and Parsonson IM (1969). Benign foot-rot – a specific interdigital dermatitis of sheep associated with infection by less proteolytic strains of Fusiformis nodosus. Australian Veterinary Journal 45:345-349.
Hudson D (1982). Footrot. Historical Materials from University of Nebraska Lincoln Extension. Paper 6.
Joe (2015). Foot Rot and Hoof Rot in Sheep. RaisingSheep.net.
Lavín S, Ruiz-Bascarán M, Marco I, Abarca ML, Crespo MJ, Franch J (2004). Foot infections associated with Arcanobacterium pyogenes in free-living fallow deer (Dama dama). Journal of Wildlife Diseases 40:607-611.
La Fontaine, Egerton JR and Rood JI (1993). Detection of Dichelobacter nodosus using species-specific oligonucleotides as PCR primers. Veterinary Microbiology 35:101 – 117.
Naylor RD, Martin PK, Jones JR and Burnell MC (1998). Isolation of spirochetes from an incident of severe virulent ovine foot rot. Veterinary Research 143:690-691.
Qureshi Beenish, Fazili MR, Handoo Nida, Ahmad RA, Dar SH and Gugjoo MB (2020). Foot affections in sheep: Clinical observations. Ruminant Science 9(2):413-418.
Roberts DS and Egerton JR (1969). The aetiology and pathogenesis of ovine foot-rot. II. The pathogenic association of Fusiformis nodosus and F. necrophorus. Journal of Comparative Pathology 79:217-227.
Stewart DJ (1989). Footrot of sheep. In: JR Egerton, WK Yong, GG Riffkin (eds), Footrot and Foot Abscess of Ruminants. CRC Press: Boca Raton, FL, pp 5-45.
Teshale S (2005). Recent footrot outbreak in Debrezeit swine farm, central Ethiopia. Journal of Veterinary Sciences 6:367-368.