Alfalfa is a popular forage choice for horses and an ingredient in many equine feeds. This legume forage can be processed and preserved in many different ways to make it easier to incorporate into the diet.
Alfalfa is nutrient-dense and is an excellent source of energy, protein and minerals in the equine diet. It is also typically low in non-structural carbohydrate content.
This makes it a valuable roughage to include in the diets of pregnant and lactating mares, mature performance horses, or other horses requiring protein supplementation.
However, some horse owners hesitate to feed alfalfa due to concerns about its safety. If you are considering adding alfalfa to your horse’s diet, and want to know if it is a good choice, then this article is for you.
Alfalfa for Horses
Alfalfa (Medicago sativa) or lucerne is a perennial legume plant that is grown as a high-yield forage crop around the world.
Alfalfa originates from the Mediterranean and southwest Asia. It has since been developed into various cultivars that can withstand a range of growing conditions.
Due to its deep root structure, alfalfa is known to be drought tolerant and grows best in well-drained, loamy soil.
Optimal growing conditions are average day temperatures of 25oC (77oF), 600 – 1200 mm annual rainfall and soil pH of 6.5 – 7.5. 
Alfalfa is a high-yielding forage crop that can produce up to 27 tons of dry matter per hectare with a higher protein yield than soybeans. 
It can be seeded for pasture grazing but requires rotational grazing strategies because it is less tolerant to intensive grazing than grasses such as timothy or teff.
Nutritional Composition of Alfalfa
Alfalfa is known as the “Queen of Forages” because of its high protein and energy content, making it an important protein source for the livestock industry. 
Below are averages and reported ranges of nutritional profiles over 200,000 legume hay samples analyzed by Equi-Analytical from 2004 – 2022: 
- Crude Protein: 21% (18 – 24%)
- Acid Detergent Fibre: 30.5% (27 – 34%)
- Neutral Detergent Fibre: 38.5% (33.5 – 43.5%)
- Water-soluble carbohydrates: 8.8% (6.8 – 10.8%)
- Ethanol-soluble carbohydrates: 6.8% (5.2 – 8.4%)
- Starch: 1.3% (0.5 – 2.15%)
Grass hays such as timothy, teff, orchard grass, or brome tend to be lower in protein and higher in neutral detergent fibre (NDF) than alfalfa hay. NSC (starch and sugar) content is also higher in grass hay.
Nutritional values vary depending on growing conditions, soil nutrient levels and harvesting conditions. The only way to know the composition of the alfalfa hay you are feeding to your horse is to submit a sample for analysis.
The major factors that influence the nutritional composition of alfalfa include: 
- Growth stage
- Cut number
- Leaf-to-stem ratio
- Moisture conditions
- Processing methods
As the plant matures, the protein content decreases and can become bound by lignin making it unavailable. The fibre (NDF and ADF) content increases with maturity. The protein content is densest in the leaves, whereas the stems are high in fibre.
The leaf-to-stem ratio is higher in earlier growth stages; at this stage, the stems are lower in fibre. The leaves are less abundant at later growth stages, and the stem becomes more rigid due to higher fibre and lignin content.
|Vegetative (30 cm)||No visible buds, flowers, or seed pods||24.6||20.1|
|Vegetative (60 cm)||May feel buds, no flowers or seed pods||22.5||24|
|Bud||Visible buds, no flowers or seed pods||19.3||30|
|Flowering||Visible flowers, no seed pods||17.8||31.5|
Alfalfa should be harvested between the late vegetative and early flowering stages to obtain the most nutritionally-dense and palatable hay while supporting plant regrowth.
Alfalfa is a high-yielding crop that can be cut several times through the growing season. In North America, three or four cuts of alfalfa hay are typically achieved in one season.
The first cut often contains weeds and other grasses, and the alfalfa may have a high stem content. Depending on growing conditions, the second cut may have a lower leaf-to-stem ratio than later cuts. 
The handling of alfalfa after cutting can significantly impact its nutritional profile. Baling at a lower moisture content increases the loss of leaves and therefore reduces the protein content.
Processing methods, such as raking during hay curing, can also affect leaf loss and nutritional value. 
Forms of Alfalfa for Horses
As a feed for horses, alfalfa can come in many shapes and sizes, from pasture to chopped hay to processed pellets. While most forms of alfalfa provide the same nutrients on a dry weight basis, some forms may have unique nutritional qualities.
Below are some of the characteristics of different forms of alfalfa.
Alfalfa pasture is generally higher in protein and energy content than grass pasture. This makes it a good option for horses in heavy exercise, growing horses and lactating mares.
Alfalfa is also a palatable forage; horses often prefer it over grass. However, some research suggests that horses prefer clover over alfalfa pasture. 
Alfalfa hay can be purchased alone or mixed with grass hay (i.e. Timothy/Alfalfa blends). Horses typically prefer alfalfa hay over grass hays, such as Bermuda or Brome hay. 
Alfalfa is easily digested and provides a good source of calories, protein, vitamins and minerals, making it ideal for horses that need a nutrient-dense diet. 
The hay is also rich in digestible fibre, which supports hindgut health and microbial fermentation. Microbes in the horse’s hindgut convert the fibre into volatile fatty acids, which are an excellent source of energy for horses. 
Alfalfa haylage is a fermented form of alfalfa that is commonly fed to dairy cattle. It provides a higher nutrient density when compared to alfalfa hay, but it must be processed and preserved properly so that mold and bacterial toxins do not form.
Haylage and silage are commonly fed to horses in Europe and other parts of the world, where frequent rainfall makes it hard to dry properly and bale hay.
Chopped alfalfa, also called green chop alfalfa, is cut and fed immediately before it has dried. This form of alfalfa is commonly fed to dairy cattle.
Green chop alfalfa has a nutritive value similar to alfalfa pasture, although its energy and protein content can vary depending on the plant’s maturity stage at the time of harvesting.
Chopped alfalfa can also be fed after it has dried, although the nutrient density is lower due to leaf fracture and loss.
Cubes and Pellets:
Alfalfa cubes and pellets are made from dried, compressed alfalfa hay. They can also be sold in a mix with other forages.
The pellets typically have a smaller particle size than alfalfa cubes. Both typically have a nutrient profile similar to alfalfa hay and are digested similarly.