I wonder if there are right-hand-riding horses and left-hand-riding horses, i.e. horses that are used to galloping on one particular side of the road.
>"Many horses are allowed to more or less 'drive themselves,'" the Saint John Globe warned, "and until the horses become accustomed to the change, drivers will have to exercise exceptional caution or collisions will surely result."
[...]
>"In Lunenburg County, 1923 is still known as The Year of Free Beef; the price of beef dropped precipitously because oxen which had been trained to keep to the left could not be retrained," according to Ivan Smith's History of Nova Scotia.
>"Oxen are notoriously slow-witted and many teamsters had to replace their oxen with new ones trained to keep to the right; the displaced oxen were sent to slaughter."
<https://www.cbc.ca/news/canada/new-brunswick/new-brunswick-d...>