Managing Natural Grazing Behavior for Impoved Pasture Productivity
by Dean Oswald - Animal Systems Educator - University of Illinois Extension
Managed grazing has long been celebrated for improved forage quality and quantity. Multiple species grazing has many potential benefits for rough, weedy or brush covered pastures. If we examine the goals of managed grazing we would expect: 1) Increased yields of high quality forage; 2) Maintained pasture stands for long periods of time; 3) Meet a large portion of livestock nutritional needs from forage and 4) Reduce the need for stored and purchased feed Meeting these goals requires an understanding of animal behavior and controlled animal feeding habits.
As we investigate species behaviors, horses have a preferred grazing height of 2-4 inches. Their upper and lower incisors permit closer grazing. Treading and hoof action may also damage forages. These factors contribute to overgrazing, poor pasture quality and weed growth. Efficient grazing heights for sheep are 2-6 inches. This demonstrates the need for managing forage stubble residues to prevent overgrazing. Cattle on the other hand prefer a taller sward of 4-10 inches tall to increase their bite efficiency. Goats have a narrower muzzle than sheep with a split upper lip which adapts them for selecting plant parts. They are top down grazers preferring tall feeds and seed heads. They prefer browsing over grazing and rough and steep land. Goats can be considered renovators and be useful to control certain weeds and unwanted vegetation. They can return a mature pasture to a vegetative, higher quality stage of production. Does this mean that cattle and goats will not overgraze? Certainly not! Managed grazing needs the watchful eye of the pasture manager and 3-4 inch minimum of pasture residue remaining when animals leave a paddock. Paddock size should be small enough for uniform grazing by the animals in the paddock within a give grazing interval.
Different forage preferences show sheep consuming many weeds or forbes even when other high quality forages are available. Goats prefer brush or browse plants including brambles, mulberry, honeysuckle and multi-fora rose for example. Cattle prefer more coarse, longer forage compared with sheep. Horses and cattle tend to have considerable un-grazed material near dung piles and urine spots. Sheep or goats will graze much of this material.
Mixed species grazing can often improve pasture utilization, productivity and control problem weeds and brush without the need for chemicals. This practice takes advantage of different grazing habits and species forage preferences. Reduced parasite loads can occur with mixed species grazing or alternating species in a grazing program. Some predator control may be achieved from larger animals protecting the smaller ruminants. Economic returns can be greater from more pounds of livestock produced per acre.
Generally in a good pasture system 6-8 goats consume as much as 1 cow or 5-6 sheep. Heavy brush-browse systems will support 9-11 goats; 6-7 sheep or a cow. With mixed species grazing 1 or 2 goats or sheep could be added per cow grazing to improve pasture utilization. This uses the different feeding habits to manage pasture and optimize animal production.
Impacts of multiple-species grazing include:
1) Positive Environmental Impact- By using proper vegetation management (rotational grazing) and well balanced pressure on vegetation (weed and brush control) we can protect our natural resources, reduce soil erosion, improve water infiltration by maintaining ground cover and forage root growth.
2) Livestock Productivity Impact – Feed quality and quantity improvement through proper forage management techniques.
3) Producer Economic Impact – More pounds of livestock produced per acre. Diversity of livestock sales throughout the year.
Managing natural grazing behavior and comingling grazing species has numerous advantages to pasture sustainability. However, certain challenges or limitations exist that deserve consideration. Increased operation cost is a factor in the overall farm budget. Added costs for livestock, feed, fencing, necessary housing and animal handling facilities may be needed. Nutrient requirements are different between animal species. Copper levels in cattle mineral can be toxic if fed to sheep. Additional labor may be needed for the operation. Increased knowledge and management skills are necessary for successful mixed species operations.