European Adder bites in dogs in southern Germany. A retrospective study over a 6.5-year period

Objective: In some regions of Germany dogs are presented to the veterinarian due to a snake bite, especially during the summer. These patients often show multiple clinical and laboratory deviations. Without a significant history diagnosis is commonly difficult. Aim of this retrospective study was to analyze exposure, physical examination and clinical pathology results as well as course and outcome in dogs presented after European adder bites.

Material and methods: Patient history of 15 dogs diagnosed with European adder bites over a 6.5-year-period were evaluated retrospectively. Normality of data distribution was tested by D'Agostino and Pearson omnibus normality test. Data were analyzed by T-test and Wilcoxon-matched-pairs-signed rank-test. P-values < 0.05 were considered significant.

Results: All 15 dogs were presented within 1-48 hours after the snakebite. Most common clinical signs were local swelling and pain. Clinical pathology results on day 1 included haemoconcentration, leukocytosis and coagulopathy. On the second day of hospitalization heart rate and haematocrit declined significantly. Treatment included fluid therapy, antibiotic and antihistaminic drugs, glucocorticosteroids, antivenom and analgesics. One of 15 dogs died on the third day of hospitalization, all others were discharged. Duration of hospitalization was between 1 and 8 days (mean 4.2 ± 1.9 days).

Clinical relevance: Dogs affected by European adder bites most often present with swelling and pain at the site of the bite, most frequently on the head and limbs. Patients require intensive symptomatic therapy including antibiotics and analgesics, if indicated. With adequate therapy survival rate is high. For some patients European adder bites may be lethal.