The quest for optimal nutrition and resource efficiency remains at the forefront of every shepherd's endeavor. One fundamental aspect of achieving this balance is strategically integrating forages into sheep diets. Forages, comprising a diverse array of grasses, legumes, and other plant varieties, are crucial to reducing feed costs and enhancing the overall health, productivity, and environmental sustainability of a sheep farming operation.
This comprehensive resource delves into the intricate world of sheep forages, exploring the choice between grasses and legume species and optimal grazing practices. Whether you're a seasoned shepherd seeking to enhance your flock's nutrition or a novice enthusiast embarking on your first forage journey, this guide will equip you with the knowledge and tools to ensure your sheep thrive on the land's bounty.
Benefits of Allowing Sheep to Forage
Allowing sheep to forage or graze on pasture offers several benefits for the animals and the farming operation.
Digestive Health
Sheep have a unique digestive system that relies on fibrous materials for proper function. Forages provide the necessary roughage to maintain a healthy digestive system. The fibrous content aids in rumination and helps prevent issues like bloat and acidosis.
Dental Health
Chewing on forages helps maintain sheep's dental health. The grinding action of their teeth while consuming forages helps keep them at an appropriate length and prevent dental issues.
Rumen Function
Forages are essential for developing and maintaining a healthy rumen, the largest compartment of a sheep's stomach. The rumen's microbial population breaks down fibrous materials, facilitating the digestion and absorption of nutrients.
Behavioral Stimulation
Grazing on forages allows sheep to exhibit natural behaviors, promoting physical activity and mental stimulation. This helps prevent boredom and reduces stress-related behaviors.
Reduced Feed Costs
Lastly, we can’t ignore the cost-benefit of grazing your sheep. High-quality forages, including lush pasture grasses and legumes, can meet a substantial portion of sheep's nutritional needs, reducing their reliance on purchased feeds.
Qualities to Look for When Choosing a Forage
Nutritional Value
When high-quality forages are grown and well managed, they can make up most, if not the entire, diet. Because of this, it’s critical to choose a forage (or a mix of forages) that meets your animals' nutritional needs.
Nutritional needs differ as animals progress through different physiological states or stages. Still, sheep should consume forage with a 7-9% crude protein concentration and a 50% total digestible nutrition (TDN) value for maintenance.
Forage Yield & Consistent Growth
Beyond nutrition, you also want to choose forages with good dry matter yields and consistent, persistent growth habits. On average, sheep consume 1.8 to 2.0% of their body weight in dry matter a day.
High-yielding plants are crucial to producing enough feed for your sheep, and efficient, consistent growth keeps your pasture productive all season.
Ideal Forages For Sheep
Small ruminants like sheep prefer different forages than cattle and horses. Sheep like small, soft, leafy plants and will eat shrub-like plants or shorter forbs before they graze on taller grasses.
When they graze, they’ll eat the leaves and anything soft before eating the stems or grasses. With this in mind, it’s good to have a variety of plant species in your pasture and turn animals out when the plants are in early vegetative stages instead of when they are more mature.
Forbs
Forbs are broad-leaved herbaceous plants that grow naturally in grasslands, meadows, and pastures. Unlike grasses, characterized by narrow leaves, forbs have broader leaves and diverse flowering patterns. Forbs encompass various plant species, including wildflowers, herbs, and non-grass vegetation.
They are essential in providing diversity and nutritional balance in sheep diets. Compared to grasses, they often contain different nutrients and secondary compounds that can complement the overall nutritional profile of the pasture.
- Chicory is a high-quality, palatable forage with crude protein levels ranging from 10% to 32%. New plantings can produce 2-3 tons of dry matter per acre and 4-6 tons per acre in established stands. It is well suited for finishing lambs or carrying ewes and lambs during lactation. Chicory is known for its ability to withstand high grazing pressure.
- Plantain is high-yielding and highly palatable to sheep. Under optimal management, it can yield about 6 tons of dry matter per acre. One drawback to plantain is that it doesn’t compete well in mixed swards, and its persistence is significantly reduced.
- Dandelion can also be a helpful forb in sheep pastures. Animals don’t consider them a weed but readily graze on them for the variety they offer.
- Brassicas are annual crops that can extend the grazing season into the late fall or early winter. They include rape, kale, swede, and turnips like Purple Top, York Globe, and Seven Top.
Legumes
Several legume options stand out when selecting sheep pastures because of their nutritional value, palatability, and adaptability to various growing conditions.
- Alfalfa, white clover, red clover, and birdsfoot trefoil make excellent forage choices. They’re higher in protein, fiber (essential for digestive health), calcium, and carotene than grasses. Their nutritional value makes them especially valuable during periods of high nutritional demand, such as lactation.
Cool-Season Grasses
Cool-season grasses make excellent forages since they grow abundantly in spring and fall when temperatures are cooler, providing early and late-season grazing. They also typically retain forage quality as the season progresses better than warm-season types.
- Forage Kentucky bluegrass is very palatable, highly nutritious, and tolerant of frequent, close grazing—it grows taller and leafier than varieties used for home lawns. It forms a tight sod that provides sound footing for grazing animals.
- Perennial, annual, and intermediate ryegrasses are highly nutritious and recover rapidly from frequent, close grazing. All ryegrasses establish quickly and are tolerant of rocky or poor soils. Perennial types are better for cooler, northern climates; annual ryegrasses are not cold-tolerant.
- Endophyte-free tall fescue (Fawn Tall Fescue, Cajun II, Kentucky 32) has excellent fall productivity to extend the grazing season and is moderately tolerant of continuous grazing. Tall fescue species are also good at resisting weeds, insects, and diseases.
- Orchardgrass (Dactylis glomerata) is a highly productive forage option for grazing and hay production. It’s clean and sweet-smelling, with excellent palatability. Building an appropriate ration with orchard grass as a foundation forage is easy. Deer Creek Seed’s Amplify Brand Orchardgrass has moderate winter hardiness and grows quickly.
- Timothy grass (Phleum pratense) is full of fiber—excellent for gut health—and has a balanced ratio of calcium and phosphorus, helping maintain bone health. It produces abundant leaves in midsummer when other forages slow their growth due to the heat.
- Reed canarygrass is another cool-season perennial grass used for pasture or hay. Although it is difficult to establish because of slow emergence, once established, it is vigorous and forms a dense sod that can withstand sheep hooves. One advantage of reed canary grass is its ability to tolerate various soil conditions, including poorly drained soils. It can thrive in wet or marginal areas where other forage species may struggle to establish.
- Bromegrass is known for its high yield potential, palatability, and adaptability to various soil types and climates. It is high in crude protein and relatively low in crude fiber content. Its deep root system enables it to withstand drought conditions and recover quickly after grazing, making it suitable for intensive grazing systems.
Warm-Season Grasses
Warm-season grasses are valuable pasture forages, especially in northern climates. They are more tolerant of high temperatures and provide grazable material during the summer slump when cool-season grasses slow down or quit growing. These grasses also typically offer higher fiber content and lower crude protein and nonstructural carbohydrates than their cool-season counterparts.
- Bermudagrass produces large amounts of dry matter and can offer high nutritional value for your animals. It tolerates grazing pressure, and its crude protein content responds well to nitrogen fertilizer applications. Some cold-hardy forage varieties that establish well from seed are available.
- Bahiagrass provides nutritious forage for sheep throughout the grazing season, with peak production occurring in the warmer months. One of the critical advantages of bahiagrass as a forage for sheep is its ability to thrive in low-fertility soils and withstand drought conditions.
- Crabgrass has a deep-seated reputation as a nuisance weed, but this high-quality, palatable plant makes an excellent forage for sheep. It is typically higher in nutritional value and digestibility than other warm-season grasses, including Bermuda and Old World bluestems.
- Indiangrass is highly palatable to sheep flocks and, when correctly managed, suitable for grazing and hay. This native grass is a good pasture addition for arid climates; it prefers dry climates and limited rainfall.
- Pearl millet is commonly grown for forage, wildlife, or as a cover crop. Under ideal conditions, it can reach 3 to 5 feet tall. This multi-cut forage grass is preferred over other millets for hay, pasture, and silage production because it is highly digestible, high in protein, and free of prussic acid.
Forages to Avoid With Sheep
While many forages are suitable for sheep, some should be used cautiously or avoided due to potential toxicity or poor nutritional content.
- Johnsongrass can accumulate toxic levels of cyanide, especially when stressed by drought or frost. Ingesting large amounts of cyanogenic plants can be lethal to sheep.
- Certain lupine species contain toxic alkaloids to sheep, causing a condition known as "lupinosis." Sheep grazing on lupine-rich pastures may exhibit symptoms such as muscle twitching, convulsions, and, in severe cases, death.
- White snakeroot contains tremetol, which can cause "milk sickness" in sheep. Symptoms include tremors, incoordination, and respiratory distress.
- Bracken fern contains thiaminase, an enzyme that breaks down thiamine (vitamin B1). Ingesting large amounts of bracken fern can cause thiamine deficiency, resulting in neurological issues.
- Nightshade plants, such as horsenettle and black nightshade, can be toxic to sheep. They contain solanine, which can cause symptoms like drooling, diarrhea, and respiratory distress.
- Oleander is highly toxic to sheep, containing compounds known as cardiac glycosides. Ingesting even small amounts can lead to severe cardiovascular issues and may be fatal.
- Alsike clover can harbor slaframine, a toxin produced by certain fungi. Ingesting slaframine causes slobbers (excessive salivation).
Are Forage Grasses or Legumes Better for Sheep Pastures?
Growing mono stands of grasses or legumes has advantages and drawbacks. Since both offer excellent forage potential, it’s hard to say which is better.
Pros of Forage Grasses
✓ High fiber content
✓ Longer growing season
✓ Tolerant of frequent, close grazing
✓ Establish quickly
✓ Tolerant of a variety of soils
✓ Better drought tolerance over legumes
✓ Can be grazed or used for hay
Cons of Forage Grasses
✗ Lower crude protein
✗ Less tolerant of trampling
✗ Lower yields
Photo Source: Jeffrey Surianto | Pexels
Pros of Forage Legumes
✓ High in crude protein
✓ Nitrogen fixation lowers fertilizer costs
✓ Improved palatability and digestibility
✓ Useful for grazing or hay
Cons of Forage Legumes
✗ Less tolerant of heat, cold, and drought
✗ Higher management requirements
Photo Source: Wikimedia Commons
Growing Mixed Species Pastures
Instead of growing mono stands, many producers plant mixed forage pastures that include multiple grass or legume species or legumes and grasses to reap more benefits. Some of the advantages of mixed species pastures include:
- Increased dry matter weight and crop yield
- Reduced weed competition
- Improved distribution of forage growth through the season
- Greater adaptability to weather conditions
- Reduced nitrogen fertilizer needs from the leguminous nitrogen-fixation
Looking for high-quality pasture mixtures? Deer Creek Seed offers the following selections that are fantastic for sheep.
- #4 Pasture Mix
- Pastureland Over-Seeder South
- Premium Grass Base Forage Mix
- Premium Lowland Clover Mix
- Wetland & Waterway Mix
If you try a grass-legume pasture mix, keep it simple: two grass species and one legume are recommended starting points.
Forage Quality Analysis
Three principal quality parameters are commonly used when evaluating forages, whether pasture, hay, or silage: crude protein (CP), neutral detergent fiber (NDF), and acid detergent fiber (ADF).
Parameters such as total digestible nutrients (TDN), net energies, and mineral concentrations are also commonly reported for sheep that rely heavily on forages for their diet.
Understanding Crude Protein (CP)
Forages and other feeds are analyzed for crude protein (CP), the combined percentage of true protein and non-protein nitrogen. This number tells a forage’s ability to meet your sheep’s protein needs and is useful when developing a feed ration.
- Legume forages have 20 to 24% CP.
- Spring and summer grass pastures contain upwards of 20% CP.
Understanding Fiber Content: Neutral Detergent Fiber (NDF) & Acid Detergent Fiber (ADF)
Another critical measure of a forage’s quality is the amount of fiber in the plant material, as fiber is the predominant factor in forage digestibility. The fiber content includes structural components like cellulose, hemicellulose, and lignin.
Generally speaking, fiber levels and digestibility are inversely correlated. Lower fiber means higher digestibility; higher fiber means lower digestibility.
Higher digestibility typically means higher energy value for the animal and better forage quality. Low fiber values also suggest that forage is easier to chew and is considered more palatable (i.e., sheep will consume more).
Neutral detergent fiber (NDF) and acid detergent fiber (ADF) measure a forage’s cell wall composition.
- NDF measures hemicellulose, cellulose, and lignin levels and is typically used to predict intake potential.
- In grasses, NDF < 50% is considered high quality; NDF > 60% is low.
- In legumes, NDF < 40% is considered good quality; NDF > 50% is considered poor.
- ADF measures cellulose and lignin and is commonly used to calculate digestibility.
- Forages with less than 35% ADF are typically considered high-quality.
Grasses typically contain more NDF and ADF than legumes because of greater lignification. However, you see a wide variability of NDF and ADF within grass species. And the hemicellulose, cellulose, and lignin amounts typically increase in all forages as they mature.
Understanding Moisture and Dry Matter (DM)
Dry matter (DM) is the non-moisture portion of a forage; it indicates the nutrient concentration available to your animals. The higher the dry matter, the higher the nutrients.
- Pastures typically contain 75 to 90% moisture content or 10-25% DM, regardless of the forage type.
Understanding Total Digestible Nutrients (TDN)
Total digestible nutrients (TDN) estimates the energy content of a food source. It is the sum of the digestible fiber, protein, carbohydrates, and lipids that supply energy to the animal.
TDN is directly correlated to digestible energy and is often determined using CP and ADF values.
- Low quality usually contains 45 - 52% TDN
- Mid-quality usually contains 52% - 58% TDN
- High quality usually contains greater than or equal to 58% TDN
Understanding Energy Content
The energy content of forage can be tricky to understand. At the fundamental level, the energy content of a forage (or other feed source) is the energy available to an animal for activities like growth, breathing, lactation, etc.
However, there are different ways to express energy content and some controversy surrounding this aspect of forage quality analysis.
- Gross energy (GE) is the total energy content of a forage. Not all gross energy is usable by an animal because of digestion and metabolism.
- Digestible energy (DE) is the energy of a forage absorbed by a sheep, accounting for the energy lost in feces during digestion.
- Metabolizable energy (ME) is the energy left after accounting for the energy lost during digestion from the production of urine and gases. It’s the energy available for maintenance, growth, and production.
- Net energy (NE) represents the energy the sheep’s body utilizes for maintenance, growth, and production. It’s calculated by subtracting all energies lost to metabolic processes from the metabolizable energy.
In America, the energy content of a forage is usually expressed as digestible energy (DE) and is reported in mega-calories per pound (Mcal/lb). A forage's crude protein and ADF content reasonably estimate the DE.
However, DE is considered quite archaic because there are significant differences in how digested energy is utilized from different forages and across livestock species. Keep this in mind and view DE values as an estimate.
Understanding Mineral Content
The mineral content in any plant directly reflects the soil it grew in and fertilizer management. The total mineral content is reported as “ash” in a forage analysis. Macronutrient concentrations of the macronutrients are expressed as percentages (%) or grams per pound; trace mineral concentrations are expressed as parts per million (ppm) or milligrams per pound.
All minerals reported on a forage analysis are essential nutrients for overall health. Your sheep’s diet must contain adequate quantities to satisfy daily requirements, and some nutrients must also be balanced with others.
- Calcium and phosphorus should be in a 2:1 ratio of approximately two parts calcium to one part phosphorus.
- Zinc and copper should have a 4:1 balance, with more zinc in the plant than copper.
- Iron levels should be no higher than 500 ppm; excess iron can inhibit the absorption of other nutrients and, in extreme cases, trigger insulin resistance. Legumes tend to have higher iron levels than grass forages.
Physical Assessment of Forage Hays
When choosing hay to feed your sheep, a visual inspection of the quality is as important as its chemical analysis. You’ll want to look at color, smell, maturity, leafiness, and foreign matter.
Color
Color is one of the first things you look at when inspecting forage. You preferably want the hay to be green, which indicates good nutrient content, but it should not be the primary or only focus. Remember that weeds also stay green when they’re dried.
Light or pale yellow on the outside of a bale indicates sun-bleaching. This isn’t necessarily bad as long as the sun-bleaching doesn’t penetrate the bale more than one-half to a full inch. The bleached areas on the outside will be lower in carotene and less palatable, but they don’t reduce the nutrient value too much until they extend beyond that inch mark.
A completely yellow bale typically indicates the forage was too mature when harvested, and the hay will have reduced nutrient value and even poor palatability. If in doubt, have a forage analysis to evaluate the nutrient concentration.
Dark brown or black hay is usually a sign the forage was harvested and baled when wet. Under these circumstances, fungi and bacteria feed on the nutrients, producing heat that turns the hay darker. The bale may also have a distinctively sweet odor, almost like caramel. Head-damaged hay may contain bacteria, fungi, or mold, potentially producing dangerous mycotoxins. It will also have reduced nutritional value, digestibility, and palatability.
Pro tip: Remember that red clover naturally turns brown as the hay dries. It doesn’t indicate poor quality but is a good reminder to identify the forage species when evaluating hay.
Smell
Hay should have a clean, fresh, slightly sweet smell. It shouldn’t smell musty or stale. If it does, there’s a chance of mold within the forage, and you should pass on purchasing it or feeding it to your animals.
Also, check for excessive dust. If a bale creates a dust cloud as you move it, it can exacerbate or trigger respiratory ailments in your sheep.
Maturity
Look at the number and size of seedheads in grass-type hays and the number of flowers in legume hays. The low presence of seedheads, smaller seedheads, and fewer flowers indicate less mature, more desirable hay.
As a forage plant matures, it becomes less nutritious. Lignin content in the cell walls increases, potentially decreasing the digestibility. The cutting number has much less impact on its nutritional value—just the maturity at harvest time.
Leafiness
Take a look at how leafy the hay is within the bale. Leaves contain more nutrients, protein, and digestible carbohydrates than stems—you want your forage source to have plenty of leaves and fewer stems and seedheads.
You also want to note stem thickness, which indicates the state of maturity of the material harvested. Hay with thick, coarse stems was harvested when it was more mature than the same species with finer stems. However, hay with fine stems that lack leaves means it was harvested too early and is immature.
Foreign Matter
Lastly, look for foreign matter that adds no nutritional value to the hay or is dangerous or inedible for the sheep. This includes insects, trash that could puncture the gut or cause an impaction, and dead animals that could introduce neurotoxins that cause botulism.
Understanding Fresh Forage Versus Hay Quality
There are some significant nutritional differences between fresh forages and hay. These differences are primarily because fresh pasture grasses and legumes have a considerably higher water content, which affects the other dietary components.
Moisture Content
- Pasture plants contain 75 - 90% water
- Hay contains 10 - 12% moisture
Hay's lesser moisture content is the main reason it can be stored successfully for periods without seeing mold growth. However, due to the hay's lower moisture content, you must increase the sheep’s water intake when feeding it hay.
Crude Protein (CP)
- Grass pastures contain 10 - 20%
- Legume pastures contain 20 - 24% protein
- Grass hays contain 6 - 10%
- Legume hays contain 12 - 20%
In general, fresh pasture forages have higher crude protein levels than hay. After harvesting, proteins undergo proteolysis, breaking them down into nonprotein nitrogen-based compounds like ammonia and urea. This breakdown reduces the CP percentage and alters the hay’s amino acid profile.
The CP of all pasture forages also declines as the season progresses and plants mature.
Fiber and Digestibility
- Early pasture forages have better digestibility than mature plants
- Fresh pasture is more digestible than hay harvested at the same time
Digestibility differences are inversely related to a forage’s fiber content. As plants mature, the lignin, cellulose, and hemicellulose concentrations increase, making them harder for animals to digest.
Vitamin Levels
- Pasture forages are higher in vitamins A, C, and E levels than hay
After forage is harvested, exposure to oxygen and sunlight degrades these essential nutrients. This degradation continues during hay storage, leading to significantly lower vitamin levels than fresh forages.
Grazing Strategies for Better Pasture Efficiency
Sheep are continuously grazed on the entire pasture or rotated through different areas to allow forages to regrow before being grazed again.
Continuous Grazing
Continuous grazing is a one-pasture system where sheep have unrestricted access to the pasture area during the grazing season. In most cases, all animals are turned out on pasture simultaneously without giving the forages any rest.
It is a simple system to manage and requires minimal capital investment, but continuous grazing usually leads to overgrazing, which results in reduced forage quantity and quality. Manure is distributed unevenly, weeds usually persist, and stocking rates generally need to be lower to provide enough forage per animal.
Rotational Grazing
Rotational grazing employs many smaller pastures, usually called paddocks or cells. Based on forage regrowth, the livestock are moved from one paddock to another every few days. The number of paddocks and rotation frequency depend upon many factors, including the class of animals and the manager's production goals.
The standard recommendation is to rotate livestock to a new paddock every 3 - 7 days, as after three days, sheep will start to come back and graze regrowth of preferred forages instead of grazing different forages.
Rotational grazing requires more management and careful oversight of the pasture, but it offers big payoffs over continuous grazing. It usually results in a higher forage output per acre, increased forage feed value, better weed control, evenly distributed manure, and higher stocking rates than those in a continuous grazing system.
One challenge with rotational grazing is providing water and shelter for the animals. Some producers solve this problem by connecting all paddocks to a single, central sacrifice lot with gates. The sacrifice lot, or dry lot, has shelter, a water source, and any supplemental feed offered. The sheep have constant access to it and can easily be rotated through the different paddocks by changing which gate is open.
Recommended Stocking Rates for Sheep Pastures
The recommended stocking rate for sheep pasture varies depending on local climate, forage type, soil fertility, and grazing management. There isn’t a one-size-fits-all answer, so it’s essential to consider your situation and the factors involved.
That said, the recommended stocking rate for sheep on pasture can range from 6 to 10 sheep per acre. This rate is for extensive grazing systems where animals primarily rely on pasture forages for their nutrition and are not heavily supplemented with feed.
Deer Creek Seed Can Help With Your Sheep Forage Needs
Whether you need help choosing between grass or legume forages or picking the best seeds for your sheep forage needs, look no further than Deer Creek Seed! Our high-quality seeds grow productive, nutritious pasture forages, and our experts are here to answer questions about seed selection or crop management.
Deer Creek Seed aims to provide you with the highest quality seed at competitive prices and exceptional customer service. Our staff works diligently to serve our customers!
Additional Resources
- Crabgrass seems unlikely as a pasture grass, but Rutgers University researchers have shown the weed’s strengths make it an excellent choice for summer forage.
- What should your forage analysis include? The Ohio State Sheep Team talks about the numbers you need.
- Whether you need help with pasture establishment, renovation, or management, Susan Schoenian, a sheep and goat specialist at the University of Maryland's Western Maryland Research & Education Center in Keedysville, Maryland, has a guide on pasture management filled with helpful information.
- Deer Creek Seed eliminates the guesswork involved in determining how and when to harvest forages for hay or silage.