A horse that makes a strange noise when he’s exercising at high speed could be a roarer with a lazy flapper. What’s that you say?

More technically, the horse might have recurrent laryngeal hemiplegia, a degenerative upper-airway condition generally referred to as ‘roaring.’ The condition occurs when the nerve supplying one or both of the cricoarytenoid dorsalis muscles near the larynx (the voicebox) is damaged and becomes fully or partially paralyzed.

What Causes Roaring in Horses?

The arytenoids, essentially big pieces of cartilage on either side of the larynx, usually close over the trachea (windpipe) when a horse swallows and then open quickly to allow breathing. When paralysis sets in, the arytenoid (colloquially “the flapper”) flops into the larynx. Because the larynx acts as a valve to regulate airflow into the trachea and then on to the lungs, the dangly bit not only creates the whistling or roaring noise, but due to reduced oxygen reaching the lungs, also results in progressive exercise intolerance.

Advertisement