Gut Microbiome Alterations in Canine Idiopathic Epilepsy: A Pairwise Case-Control Study

Area of Science:

• Veterinary Neurology
• Microbiome Research
• Canine Health

Background:

• Idiopathic epilepsy (IE) is a prevalent neurological disorder in dogs with unknown etiology.
• The microbiota-gut-brain axis is increasingly implicated in neurological conditions, including IE.
• Understanding the canine gut microbiome's role in IE is crucial for advancing diagnostics and therapeutics.

Purpose of the Study:

• To investigate alterations in the fecal microbiome composition of dogs with idiopathic epilepsy compared to healthy controls.
• To identify specific bacterial taxa associated with IE using robust statistical methods.
• To explore potential links between the gut microbiome and the microbiota-gut-brain axis in canine epilepsy.

Main Methods:

• A case-control observational study involving 98 dogs (49 IE, 49 controls).
• Fecal samples were analyzed using 16S rRNA gene sequencing to characterize the gut microbiome.
• Six differential abundance methods were employed to identify significant microbial variations between groups.

Main Results:

• A modest but significant shift in overall microbial community structure (Weighted-Unifrac distance, P = 0.042) was observed in IE dogs.
• One specific amplicon sequencing variant (ASV) of the genus *Collinsella* was consistently more abundant in IE dogs across all tested methods.
• Gut microbial composition varied significantly by household but not by dog's sex, age, or breed. Phenobarbital treatment did not alter the microbiome.

Conclusions:

• The study suggests a significant association between gut microbiome alterations and idiopathic epilepsy in dogs.
• The increased abundance of *Collinsella* in IE dogs warrants further investigation into its specific role.
• Elucidating the precise mechanisms underlying the gut microbiome-IE relationship is essential for future research.