We have been measuring tracheas for some time now. It isn't common practice in Australia to do so, but I am so pleased to hear that other breeders are on board so more and more are starting to be done. A trachea changes in that first 12 months of life as their bodies grow and they are impacted by their owner’s lifestyle choices.
See some of our dogs tracheas below and please keep reading for more great info!
Our Cydi’s gorgeous trachea at 0.19 ratio
Harlie's 0:20 tracheal ratio
Ryobis trachea with a 0:21 ratio
The below is a shared post from "Brachy 101" Facebook group -great info courtesy of Lea Malory Archer, thank you!
What is Tracheal Hypoplasia?
Tracheal hypoplasia is a narrowing of the trachea that is present from birth. The trachea is made up of multiple cartilage rings, and in affected dogs the growth of these ring is inadequate. The trachea does not always grow at the same rate as a puppy and in some cases, it will require careful management until the puppy outgrows the condition.
Tracheal hypoplasia is one component of brachycephalic airway obstruction complex.
Affected animals may present. with strider (wheeze), dyspnoea (laboured breathing), reduced exercise tolerance and coughing. Excitement can make the condition worse.
It is not known whether this is a hereditary problem, however affected dogs should not be bred from.
Tracheal hypoplasia is diagnosed by Xray over the age of 12 months. For USA requirements the dog must be awake during the xray, other countries may anaesthetise the dog. The Xray is taken at peak inspiration (breathing in).
Measurements are then taken at the Thoracic Inlet, TI (number 1 in the diagram) and the diameter of the trachea TD (Number 2).
This is then written as a ratio. In Bulldogs a TD/TI ratio of 0:116 is considered the average. A ratio below this number would be considered tracheal hypoplasia, a ratio above this would be good.
There are also other measurement methods used to establish a ratio.
Below are X ray examples of normal trachea and a narrow (hypoplastic) trachea, there is also a diagram showing where the measurements are taken.
Information courtesy of Linda Dempsey.
