Ultrasonographic evidence of gastrointestinal hypomotility in dogs with tick paralysis (Ixodes holocyclus): a prospective pilot study.

Tick paralysis (TP) caused by Ixodes holocyclus is associated with regurgitation, vomiting and an increased risk of aspiration pneumonia. However, objective assessment of gastrointestinal (GI) motility in affected dogs has not been systematically described. The aim of this prospective pilot study was to evaluate GI motility using 2D ultrasonography in dogs with TP at hospital admission compared to healthy and disease controls and to assess short-term changes following sedation. Seven dogs with TP and eight each of healthy and disease controls were enrolled. Gastric, duodenal and jejunal contractions were counted over 3 min at standardised anatomical sites, and in dogs with TP reassessed 30-60 min following administration of butorphanol with or without acepromazine. Dogs with TP had lower contraction frequencies than healthy controls in the stomach (Hodges-Lehmann difference -2.5 [Confidence interval -4.00 to -1.33], P = 0.014), duodenum (-3.67 [-4.00 to -2.33] P = 0.002) and jejunum (-2.67 [-4.33 to -1.67] P = 0.002). Following sedation, contraction frequency reduced further or remained absent. No statistically significant differences were detected between TP and disease controls. Although limited by small case numbers, these findings provide preliminary objective evidence of generalised GI hypomotility in dogs with TP, which appears to be exacerbated by commonly used sedative protocols. These results support the clinical perception of ileus in TP and highlight the need for larger prospective studies to further characterise the prevalence, severity and clinical implications of GI dysmotility in this population.