Question

I read with great interest your article titled “Revelations About Ponies and Pastures.” I breed Miniature Horses, and have encountered some problems with obesity. I would like to incorporate muzzled grazing into the diets of my horses. We are just coming into summer here in Queensland (Australia), and the summer grasses are starting to grow. My questions relate to the type of muzzle to use and how much grass I can expect a Miniature Horse to consume in four hours of grazing. Rubber muzzles are available here in Australia, and these have a hole in the base for the horse to graze through. Is this type suitable? Would the horse be more likely to consume weeds if their mouth is restricted by a muzzle? Does the grass need to very long for the horse to access it as part of the diet, as opposed to just playing? Would the total-consumption figures for ponies in your article be the same for a Miniature Horse?

Answer

The muzzle you described in your question sounds nearly identical to ones typically used in the United States, so it should work fine. As with any piece of equipment, fit is important. Muzzles adjusted too tightly can cause rubs and hair loss, and those fitted too loosely can be challenging to keep on the horse. 

In regard to weed consumption, horses would likely maintain the same selectivity in plant choices as they would when unmuzzled. The amount of grass horses eat when muzzled is probably somewhat dependent on grass height. The horses will have to work a lot harder, for little reward, when the grass is short.

In terms of quantity eaten, I would suspect that the Miniature Horses would eat similar amounts as the ponies in the study mentioned in my article: 3.8% of body weight when left unmuzzled all day on pasture; 0.8% of body weight during three hours of unmuzzled turnout; and 0.14% of body weight during three hours of muzzled turnout. Be sure to feed adequate hay (at least 1.5% of body weight) when the horses are not on the pasture.