Written by: Niels Harmuth (Agronomist)
Multispecies grazing refers to the use of more than one species of herbivores to graze a common forage resource.
Photo credit: Bertie Coetzee (Lowerland, Prieska)
The overriding principle favouring multispecies grazing is that intraspecific (between individuals of the same species) competition is always greater than interspecific (between different species) competition. This can also be described by the ecological principle that a niche defines the ultimate distributional unit and no two species living in the same area can occupy the same niche. Each species of animal, whether wild or domesticated, will tend to exploit different portions of a common environment. Thus competition for limiting resources has led ungulates in a given area to occupy different dietary niches, to develop complementary forage preferences and grazing habits.
Benefits of multispecies grazing:
Cattle prefer grass over other types of plants and are less likely to be selective when grazing than sheep or goats. Sheep and goats will also eat weeds. Goats also have a preference for browsing on brush and shrubs.
Grazing cattle, sheep and goats together on a diverse pasture should result in all types of plants being eaten, therefore controlling weeds and brush. This should yield more kilograms per hectare compared to single species grazing.
Recommended multiple species cover crops would be both beneficial and suitable for multispecies grazing.
Adding goats to cattle pasture can reduce browse plants and broad-leaved weeds. This permits more grass growth. Adding just one goat per cow should not affect cattle performance and is a cheap way of rejuvenating pastures. The same principle applies to sheep.
Supplemental feeding can be a problem, including the feeding of trace elements/minerals. A mineral supplement that is adequate for sheep may not be so for cattle, and the mineral supplement that is best for cattle may be toxic to sheep. Copper comes to mind in this case. This difficulty, and the one of aggressive animals may be overcome by simply rotating the animals. If sheep are grazed for a few days and then moved to a fresh pasture the next species can follow where the sheep have been. This can be beneficial to the pasture and avoid the problems mentioned.
Fencing is another issue to consider. Fencing for cattle may not be adequate for controlling sheep or goats. Electric fencing is generally considered to be the most economical and convenient.
Parasites are a major concern for sheep and goats under any system. Parasites are species specific; cattle parasites affect cattle and not sheep or goats, while parasites from the latter do not affect cattle. Cattle can act as vacuum cleaners ingesting sheep or goat worm larvae and thus preventing them from affecting sheep or goats. This is most useful when sheep and cattle follow each other in a grazing system. Remember sheep and goats do share parasites, therefore grazing them together does not improve parasite control. Because parasite eggs are deposited in the manure, and larvae only travel a short distance up grass blades, animals grazing taller forages will not consume worm eggs or larvae. Goats therefore, given ample browse, will be much lest likely infested with parasites. However, if goats are forced to graze at ground level, they can acquire a serious parasite load.
In summary the basic principles of grazing management are control of:
1. Intensity of grazing (stocking rate)
2. Timing of grazing
3. Kind and class of herbivore
4. Distribution of grazing