Fig. 1

Line plot showing the incidence rate of canine megaoesophagus (expressed as the number of cases per 100,000 dogs per day) 1 January 2012 to 15 February 2018. The solid line shows the point estimate of megaoesophagus incidence rate as a function of calendar date. The lower and upper dashed lines show the lower and upper 95% confidence intervals around the incidence rate estimates. Superimposed on this plot is a frequency histogram showing date of onset of clinical signs for megaoesophagus cases used in the case-control study