It’s no secret that horses in modern management situations can benefit from slowed forage intake, which mimics feral horses' natural foraging tendencies. But do these slow feeders really work? A group of University of Minnesota researchers recently put two slow-feed haynets—one with medium-sized and one with small-sized openings—to the test to find out.
“The small and medium haynets offer two different size options in the ‘slow-feed’ haynet market,” said Krishona Martinson, PhD, associate professor and Equine Extension Specialist at the University of Minnesota. "We wanted to see if there was a difference between these haynets."
The researchers also wanted to see how the two slow-feed nets compared to a standard haynet or no haynet at all. The researchers employed eight healthy adult horses in their two-part study, using four treatments:
- A standard net with 6-inch openings;
- A "medium" net with 1.75-inch openings;
- A "small" net with 1.25-inch openings; and
- No net with hay fed on the stall floor.
The researchers offered the horses hay at 1% body weight twice daily in individual stalls and allowed the animals four hours to eat their mixed-grass hay from one of the treatment protocols. At the end of each four-hour period, the researchers removed the haynets and weighed the remaining hay from the net and the floor. Each horse received each treatment twice during the eight-week study.
Ultimately, the team found no difference in the amount of hay consumed between the standard haynet and control treatment. Horses in both treatment groups finished eating their hay in about three hours.
On the other hand, the medium and small nets increased horses' consumption time considerably. Since none of the horses in the small net treatment and only five of eight horses in the medium net treatment were able to consume all their hay in the four-hour time period, the researchers devised a second experiment to determine how long it would take horses to finish hay from the small- and medium-holed haynets.
In this experiment the researchers split the same eight horses into two groups and assigned them to either the small or medium net treatment for seven days. Then, the horses switched treatment groups and repeated the same process for another week. This time horses were allowed continuous access to hay until they either finished it or showed no interest in eating for 10 minutes or longer.
The researchers found that horses with the medium net finished their hay in an average of 5.1 hours, while horses with the small net took an average of 6.5 hours to finish their hay.
“The use of haynets with small and medium openings offers horse owners … a practical and affordable option to reduce dry matter intake rates and extend foraging time in adult horses,” the team concluded.
The study, "The Effect of Haynet Design on Rate of Forage Consumption when Feeding Adult Horses," was published in Journal of Equine Veterinary Science.
Disclaimer: Seek the advice of a qualified veterinarian before proceeding with any diagnosis, treatment, or therapy.