Abstract
ABSTRACT
Digital dermatitis (DD) is the leading cause of lameness in cattle, posing major animal welfare and economic concerns. Effective prevention strategies are increasingly important given emerging antimicrobial resistance associated with common DD treatments. Supplementation with
Saccharomyces cerevisiae
fermentation postbiotics (SCFP) has been shown to enhance innate immunity and reduce DD lesion development. This study evaluated the effect of a commercial SCFP supplement on the microbial composition of DD lesions using shotgun metagenomic sequencing to characterize microbial communities and associated antimicrobial resistance genes. Beta diversity analysis revealed that stage M4 DD lesions from SCFP-supplemented cows had a trend for different microbial compositions compared with controls (
P
= 0.051). At the genus level, M2 lesions were found to have statistically significant lower abundance of the genera
Desulfovibrio
,
Pseudomonas
,
Staphylococcus
,
Anaerotignum
,
Caproicibacterium
, and
Bacteroides
in the SCFP treatment group compared with the control (
P
Fusobacterium
,
Citricoccus
,
Listeria
, and
Fundicoccus
as compared with the control (
P
Blautia
and
Petrimonas
in the SCFP treatment group compared with the control (
P
Desulfovibrio sp. G11
,
Anaerotignum sp. MB30-C6
,
Caproicibacterium argilliputei
, and
Prevotella intermedia
in the SCFP treatment group compared with the control (
P
Fundicoccus culcitae
and
Helcococcus ovis
as compared with the control (
P
IMPORTANCE
Digital dermatitis (DD) causes substantial economic loss and welfare concerns in cattle production systems worldwide. Our findings show that dietary supplementation with
Saccharomyces cerevisiae
fermentation postbiotics (SCFP) has the potential to alter the microbial ecology of DD lesions. Importantly, this work identifies antimicrobial resistance genes within DD lesions, underscoring the limitations of antibiotic-based control strategies. By linking nutritional supplementation to changes in microbial communities and resistance gene profiles, this study advances understanding of non-antibiotic approaches to disease mitigation and supports the development of sustainable, microbiome-informed management practices in food animal production.