Turning a horse out should not be a problem; however, grazing muzzles are often used when a horse is turned out to pasture. Why are grazing muzzles used? Actually, there are several reasons to use a grazing muzzle, although, I must admit my horses hated them!

• Reduce sugar intake if a horse is insulin resistant.
• Management of an easy keeper's weight while at pasture.
• Restrict food intake in obese horses.
• Restrict intake of unwanted articles for horses with pica.
• Restrict cribbing.
• Restrict unwanted vices such as horses habitually biting.

When using a grazing muzzle there are certain safety rules one should consider.

• A breakaway feature. Must have a break away strap. I like leather because it is less likely to hang up than nylon.
• Must fit properly to
• Adjustable hook and loop straps.
• 1" opening to limit grass intake.
• Horse must be able to drink water without any inhibition.

The study, "Interaction of Grazing Muzzle Use and Grass Species on Forage Intake of Horses," was published in the Journal of Equine Veterinary Science. Interaction of Grazing Muzzle Use and Grass Species on Forage Intake of Horses/Abstract

Emily C. Glunk, MS Craig C. Sheaffer, PhD, Marcia R. Hathaway, PhD, Krishona L. Martinson, PhDemail
Received: February 20, 2014; Received in revised form: April 16, 2014; Accepted: April 29, 2014; Published Online: May 06, 2014

"The impact of horse preference and grass morphology on grazing muzzle effectiveness has not been investigated. The objective of this study was to determine the effectiveness of grazing muzzle use at reducing forage intake when horses grazed grasses with different morphology and preferences. The study was conducted in 2012 and 2013. Four horses were grazed in 2012, and three horses were grazed in 2013. Four species of perennial cool-season grasses were grazed in 2012 including Kentucky bluegrass (Poa pratensis L.), meadow fescue (Schedonorus pratensis Huds.), perennial ryegrass (Lolium perenne L.), and reed canarygrass (Phalaris arundinacea L.). In 2013, only Kentucky bluegrass and reed canarygrass were grazed because of winter kill of other species. Horses were allowed to graze a small pasture seeded with an individual species for 4 hours each day in June and August of 2012 and August and September of 2013. Horses grazed the same grass species for two consecutive days, one day with a muzzle and one day without. Before and after each grazing, a strip was mechanically harvested to determine initial and residual herbage mass. The difference was used to estimate forage intake. The effectiveness of a grazing muzzle was not affected by forage species (P = .05). Use of a grazing muzzle decreased the amount of forage consumed by an average of 30% compared with not using a grazing muzzle (P < .0001). Results will aid horse owners and professionals in estimating forage intake of muzzled horses on pasture."