Grazing Management for Sheep Production
Effective grazing management is an important part of the overall ranch or farm business. It combines livestock management, forage management and farm business management. A grazing management plan includes setting goals with available resources, creating and implementing an adaptive plan, followed by monitoring and adjusting. Creating a grazing management plan helps recognize weaknesses in the operation by identifying what resources they have and what they need.
It is important that operational goals are clearly stated and are specific, measurable, action-orientated, realistic and time-based. Identify where the operation is currently and clearly define where the operation will be in a set period of time. Goals can be short term, intermediate or long term. For example, a grazer may identify a low-producing overgrazed field in their grazing rotation. A goal for this field may be to increase litter levels to 400 lbs per acre in three growing seasons by decreasing forage utilization to 25 per cent removal per year. Every operation is unique in their operational goals and capabilities.
There are many different tools and infrastructure available to a grazer to assist with managing livestock grazing. Operators must first outline what infrastructure currently exists. This can include (but is not limited to) land, permanent and temporary fencing, water systems, lambing facilities and barns. It also includes existing labour capabilities. Once the existing infrastructure is inventoried, determine additional requirements that are needed to reach the operational goals.
Sheep can be managed with a number of or a combination of different fence types. It is important to consider not only keeping the sheep in the field, but also keeping predators such as coyotes or wolves out. Woven or high-tensile electric fences are common for perimeter fencing. High-tensile electric fence can be constructed to electrify some or all of the wires, enhancing predator control and livestock management. Interior fences can be permanent or temporary. Temporary fencing is a useful tool that can create flexible, multi-sized grazing areas to use at different times and locations throughout the grazing season. When inventorying and planning fencing, calculate the Fencing Costs as an addition to routine maintenance and repair costs.
Water and water systems
Water is the most essential nutrient in a livestock grazing system. Sheep require clean, good-quality water. Poor water quality can reduce livestock performance, impair reproduction, and cause livestock death. Water should be tested to ensure it is suitable for animal health and welfare.
Sheep consume eight to 12 litres of water per day. They will walk approximately 1.5 miles (2.4 kilometres) to water, but will not often travel farther than 2.5 miles (four kilometres) to reach water. Sheep are less able to access drinking water from dugouts than cattle are. Direct access to dugouts and other natural water sources increases the risk of contaminating the water and reducing water quality. Water can be delivered from dugouts, natural water sources, and wells by pasture pipelines, permanent or temporary solar water systems or by water hauling.
Sheep, especially lambs and sick or old sheep, are susceptible to injury and death from predators. The most common predator throughout Saskatchewan is the coyote. Other predators present in some areas of the province include wolves, bears, cougars, and ravens. Livestock guardian dogs are excellent resources for livestock protection. Some breeds of livestock guardian dogs are Turkish Kangal, Great Pyrenees, Maremma and Anatolian Shepherds. The number of dogs needed will depend on the operation's goals, landscape and predator threat.
Balance Animal Inventory with Available Forage Inventory
Forage supply and animal demand need to be balanced to ensure the nutrient demands of livestock are met and to ensure the health and sustainability of the forage stand. This balance is referred to as carrying capacity. Carrying capacity in tame pastures can be estimated using Initial Stocking Rate Recommendations for Seeded Pastures in Saskatchewan. Carrying capacity in native pastures can be estimated using Saskatchewan Rangeland Ecosystems: Ecosite Guide. Both resources express forage supply estimates based on Animal Unit Months (AUMs) per acre. An AUM is the amount of forage consumed by an 1000 lb. cow for one month. Adjustments are made for different livestock types and expressed as Animal Unit Equivalents (AUE).
|Table 1 Sheep Animal Unit Equivalents
|5 (100 lb.) ewes (with or without unweaned lambs)
|Weaned lamb/kid (to 12 months old)
|Source: Grazing Management for Healthy Rangelands 2008
Carrying capacity can also be determined by clipping and weighing samples from a field using the following method:
- Clip five to 15 representative samples from a 1.92 square foot area.
- Dry and weigh samples.
- Average the weight of the samples then multiply by 50 to calculate the pounds of forage per acre.
- Apply a 25 per cent harvest efficiency rate (what the livestock will consume). Over time, harvest efficiency can be adjusted based on monitoring. Generally, tame pastures have a higher harvest efficiency rate than tame pastures.
Ranchers Guide to Grassland Management IV
Grazing Management Plan
A grazing management plan is based on grazing management principles including:
- Provide adequate rest – Plants require time in the growing season to recover from grazing. Adequate rest ensures plants can replace leaves that will continue the process of photosynthesis and replace roots that will continue nutrient and water uptake within the soil profile.
- Balance livestock demand with forage supply – It is important to balance the number of animals with available forage. Grazing too many animals with not enough forage creates serious problems for animal performance and rangeland health.
- Timing of grazing – The recovery for plants changes as the time of grazing changes. Plants grazed in the spring and summer are rapidly growing and are most susceptible to grazing. Ensure adequate rest matches the timing of the grazing period.
- Animal distribution – Livestock will graze near water areas and familiar areas repeatedly which can lead to over-grazing some areas under-grazing others. Distribution can be managed with tools such as planned water development, salt placement and temporary electric fencing.
- Intensity, frequency and duration of grazing – Grazing intensity affects root growth and replacement. Individual grass species respond uniquely, but in general, root growth is unimpeded when 50 per cent or less of the above ground biomass is removed. When more than 50 per cent of the above ground biomass is removed, the grass responds by stopping root growth for a period of time. If grazing pressure continues frequently or for a longer duration, the roots are not replaced and, eventually, grow only close to the soil surface. Thus, they are unable to reach nutrients and water deep in the soil profile.
Monitoring rangeland health provides a documented baseline for decision-making. It allows the manager to assess impacts to the rangeland and the rangeland's response to those impacts. Some monitoring methods include:
- Rangeland/riparian health assessments
- Range inventory
- Photo reference points
- Grazing response index
To ensure successful grazing management, animal management and farm business management, include flexibility by creating a contingency plan. There are many external factors such as drought, excessive moisture, or market influences that can disrupt even the best plans. Contingency plans should address the manager's goals with potential solutions when complications arise.
Additional resource to review: An Introduction to Managed Grazing for Sheep and Goat Producers, Government of Alberta provides additional information that will assist in development of a grazing management plan for your operation.