Standardizing a freely-behaving canine videofluoroscopic swallow study protocol to investigate dysphagia in primary aging and neurological diseases

Abstract

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] The goal of this study was to establish a freely-behaving videofluoroscopic swallow study protocol (VFSS) for dogs that permits identification of translational biomarkers of dysphagia in primary aging and neurological disease conditions. A VFSS protocol was established using 49 dogs, divided into seven conditions: control, canine degenerative myelopathy, Batten disease, cricopharyngeal dysfunction, cerebellar ataxia, megaesophagus, and dysphagia of an unspecified etiology. Healthy controls dogs were further divided into three age groups: juvenile (1 month to less than or equal to 1 years), adult (> 1 to less than or equal to 10 years in small-medium breeds; (> 1 to less than or equal to 7 years in large breeds), and geriatric (>10 years in small-medium breeds; >7 in large breeds). Videos were analyzed to quantify sixteen swallow metrics. Significant differences were identified between swallow metrics of healthy controls and disease conditions. No significant differences were identified between juvenile, adult, and geriatric healthy controls. This study provides preliminary evidence that a freely-behaving canine VFSS protocol, including observation kennels, palatable recipes, and a 12-step protocol, can be used to characterize dysphagia in dogs. Additional research is needed to further validate the utility of this protocol and identify specific swallow metrics that differ between healthy controls and dogs with disease conditions. Our ultimate goal is to identify VFSS metrics that can facilitate early detection and differential diagnosis of dysphagia in dogs while serving as functional biomarkers to quantify treatment efficacy.