A. Scientists at the University of Indiana gave five older male rabbits the opportunity to listen to songs specifically selected for calming rabbits for six months. They measured the amount of the stress hormone cortisol they released into their poop. The scientists found that music therapy reduced the amount of the stress hormone in the rabbit droppings from about 12,000 picograms per milligram to about 4,000 picograms per milligram. That is a reduction of about 2/3. It is important to understand that the scientists played the songs to calm rabbits softly. They were careful to avoid cranking up the volume of their CD players. The researchers noticed that every rabbit reacted to music just a little differently and that stress levels rose again when they stopped playing the music for their rabbits. However, the beneficial effects of soft music for rabbits lasted six months.