I recently acquired a new horse, who lived on a quiet dirt road before moving to Groton Street. She has adjusted just fine to the traffic and road noise in the neighborhood, and did not even react adversely to the noise of the sirens and fire engines connected with the 4th of July parade.
She was nervous during the town fireworks display, which she could hear but not really see, but did not panic. However, on two separate occasions, she has broken through my electric fence when nearby neighbors have set off barrages of firecrackers.
She is genuinely terrified -- trembling and dripping with sweat until the explosions stop.
Fortunately, I was there both times and could catch and confine her before she could break through the pasture fence and get out on the road. But I dread every July 4th. Neighbors who have dogs also report that their animals are traumatized by the fireworks.
If you live in an area with numerous animals, think twice before lighting your Roman candles and cherry bombs -- or at least inform your neighbors with animals that you will be shooting off fireworks, and WHEN you'll be doing it, to give them time to either take the animals to a quiet area or get some tranquilizers from their veterinarians.