No Coffee Breaks for Horses By Kentucky Equine Research Staff · September 24, 2012
In regions of the world where coffee beans are grown and harvested, the discarded husks (thin outer coatings of coffee beans) have sometimes been used as bedding in horse stalls. According to a study conducted at Universidade Estadual Paulista in Sao Paulo, Brazil, this seemingly harmless use of a plentiful byproduct could be dangerous or even deadly.
Six horses in the study were placed in stalls bedded with coffee bean husks and were given a normal ration of hay. The horses showed little interest in the husks during the first 12 hours, but after sampling a few mouthfuls, they all quickly developed a preference for husks instead of hay. Within the next 48 hours the horses showed excitability, restlessness, raised heart rates, and excessive sweating, signs that are consistent with caffeine overload. Blood samples taken after 56 hours showed caffeine levels that were more than 20 times higher than what is generally considered toxic.
The horses were removed from the husk-bedded stalls and all returned to normal within 12 to 40 hours, though there are anecdotal reports of horses dying after extended exposure to coffee bean husks. The researchers concluded that this material is not a recommended bedding choice for horses.