An increasingly popular equine forage, teff grass is grown in warm geographic regions and is commonly cultivated in the Southern USA. [1][2][3] Native to Africa, teff is a warm-season grass that is high in fibre and low in sugars and starch.

The digestible energy content of teff hay varies from high to low, depending on growing conditions and crop management strategies. Because teff does not store fructans, a form of non-structural carbohydrate (NSC), it typically contains less energy than cool-season grasses.

Due to the variable NSC content, obtaining a forage analysis is recommended before feeding teff hay to horses. Low-NSC teff provides a safe forage option for metabolic horses.

Other benefits of feeding teff to horses include its palatability, high fibre content, and digestibility. [4][5]

What is Teff Hay?

Teff (Eragrostis tef), also known as summer lovegrass or annual lovegrass, is an ancient staple grain crop from Ethiopia, originally grown for human consumption. It is an annual grass that germinates quickly and is resistant to pests. [6]

Referred to as a warm-season grass, teff grows best at temperatures between 18 to 27 degrees Celsius (65 to 80 degrees Fahrenheit). [7]

Bermudagrass, crabgrass, Sudan grass, and pearl millet are also warm-season grasses. Cool-season grasses include orchard grass, tall fescue, Kentucky bluegrass, timothy, and perennial ryegrass.

Successfully cultivated in parts of the southern United States, teff grows rapidly and can be cut multiple times to maximize yield. Under optimal conditions, it produces a high yield of approximately 5 tons per acre. [1][2][3]

Teff requires a frost-free growing season. It adapts well to various soil types, including drought-stressed and waterlogged soils, and is tolerant to different soil salinity levels. [1][2][3]

Primarily used as a hay crop in the USA, teff grass has fine leaves and stems, making it a palatable option for horses. It is also useful as a low-carbohydrate forage source (depending on when it is cut) and has moderate amounts of energy and protein.

Nutritional Composition of Teff Hay

Many factors impact teff hay’s nutritional composition, including the variety of plant species, time of day, seasonal growth patterns, plant maturity, and management factors.

Digestible Energy

Compared to cool-season grasses and legumes, teff is typically lower in digestible energy (DE).

Digestible energy content of forage is calculated from its protein and fibre content, specifically the acid detergent fibre (ADF) percentage.

Like most forages, Teff can be harvested as either high-energy or low-energy hay depending on how early in its stage of growth it is cut. Protein content and thus digestible energy level rapidly decreases after the boot stage of growth and between the first and second cut of hay. [5][8]

Submit a forage sample for analysis to determine the digestible energy content of your hay.

Fibre

Compared to other tropical grasses, the fibre content is relatively low. It is a leafy forage with fibre levels similar to timothy hay.

Fibre content is measured in the lab as neutral detergent fibre (NDF) and acid detergent fibre (ADF).

NDF measures insoluble fibre and includes the plant cell wall carbohydrates: lignin, cellulose, and hemicellulose. ADF is a subfraction of NDF consisting of cellulose and lignin.

Lignin is indigestible, but hemicellulose and cellulose can be digested by microorganisms in the hindgut.

NDF can be used to predict your horse’s forage intake. In general, the higher the NDF, the less your horse is likely to voluntarily eat. Although some horses may increase their intake to make up for lower-quality forage.

Hays with NDF levels between 40-60% are suitable for equine diets. Hays with NDF values over 65% have lower intake and may not consume enough to meet energy requirements for maintenance. [9]

Non-structural Carbohydrates (NSC)

The NSC fraction of forage consists of three components:

  1. Starch
  2. Ethanol soluble carbohydrates (ESC): monosaccharides, disaccharides, and oligosaccharides
  3. Water soluble carbohydrates (WSC): fructans and pectins

Teff hay can have a non-structural carbohydrate content under 10%, depending on how it is grown. Teff is typically lower in NSCs than cool-season grasses as it does not produce fructans.

Warm-season grasses, such as teff, store carbohydrates in their plant structure as sugars and starch and do not produce fructans. In contrast, cool-season grasses do store energy as fructans.

Sugars are typically lower in warm-season versus cool-season grasses. However, starch can be higher in late-maturity warm-season grasses compared to cool-season grasses. [7]

Fatty Acids

Teff is comprised of approximately 2.7% fat, primarily in the form of linoleic acid (omega-6). Teff also contains polyunsaturated fatty acids including alpha-linolenic acid (omega-3) and oleic acid (omega-9) and palmitic acid, a saturated fatty acid. [10]

Protein

The protein content and digestibility of teff decrease with increased plant maturity. [5] Crude protein levels in teff range between 11 – 18%. [11]

A study of various forages, including teff, found that typical protein content exceeded the requirement for mature horses in moderate exercise with a daily intake of 2.5% of body weight. [12]

Vitamins and Minerals

Teff contains low levels of key minerals, including zinc and copper. [11] Horses consuming teff hay require supplementation to avoid deficiency in these trace minerals. [5]

The calcium and phosphorous levels in teff are comparable to timothy grass and close to an optimal ratio of 2:1 Ca:P.

Benefits of Feeding Teff Hay

1) Low in Non-Structural Carbohydrates

The NSC content of teff forage ranges from 5.4% (at boot stage maturity) to 8.4% (at late stage maturity). At all stages of growth, non-structural carbohydrates measure below 10%. [5]

Forages containing less than 10% NSCs are generally considered safe for horses with metabolic conditions such as: [13]

Feeding low-NSC forages helps to maintain normal blood glucose (sugar) and insulin levels in horses. [14][15][16]

Consuming pasture grasses with greater than 10% NSC can worsen hyperinsulinemia in insulin-resistant horses and potentially trigger laminitis.

Fall grazing presents a risk for metabolic horses because warm days and cool nights increase NSCs in cool-season grasses. Research shows that horses grazing on teff in the fall have lower blood sugar and insulin levels than horses grazing cool-season grasses and legumes. [13]

2) High in Fiber

Horses should be provided with a forage that they can consume free-choice and meet their energy requirements.

The high fibre content in teff tends to slow down feed intake, which is an advantage for horses requiring an energy-restricted diet.

3) Palatable

Teff is a palatable forage for horses due to its fine stems and leafy composition.

Horses unaccustomed to teff generally prefer mature alfalfa and timothy hay over teff hay. [17] However, horses consumed the same amount of mature teff as mature timothy if not given a choice between forages. [17]

Like other forages, the quality and palatability are largely affected by environmental conditions, maturity at the time of harvest, and production and cultivation methods.

Researchers assessed the intake of teff hay cut at three different stages of growth (boot stage when the developing seedhead is still in the leaf sheath of the uppermost leaf, early maturity, and late maturity).

Horses prefer boot and early maturity teff with lower fibre content than late maturity teff hay. [17]

4) Easily Digested in Early Growth Stages

Since teff plants are fine-stemmed, they are easy for horses to chew and digest. Teff grass is softer and leafier than other hay grasses when harvested in the boot and early growth stages.

Digestibility of non-fibre carbohydrates and water-soluble carbohydrates increases from boot to early-heading to late-heading hay. [5]

Digestibility of crude protein and fibre decreases as teff hay matures from boot to late-heading stages of growth. [5]

5) Suitable for Horses with Low Energy Demands

Because teff forage contains less than 10% NSC and is high in fibre, it is suitable for horses with lower energy demands. This includes easy keepers and overweight horses. [5]

Teff provides lower digestible energy than cool-season forage varieties. However, boot and early heading maturities of teff hay meet 90 to 97% of the average dietary energy needs of horses. [5]

The overall digestibility and nutrient concentration of teff decline with maturity. Late maturity teff does not meet the dietary energy and crude protein requirements of most horses. [5]

Horses with higher nutrient requirements may require additional feeds or other forages to meet energy and protein needs.

Considerations When Feeding Teff Hay

Quality of Protein in Teff

Teff is a lower-quality protein than other forages. Compared to teff, alfalfa and cool-season grasses contain higher levels of most amino acids.

Amino acids are the building blocks of protein and are important for muscle repair and recovery following exercise. Ten essential amino acids must be provided in your horse’s diet because they cannot be synthesized in the body.

Lysine, methionine, and threonine are considered limiting amino acids because they are the most likely to be deficient in the equine diet. [18] Protein synthesis can be compromised if one of these essential amino acids is not supplied adequately.

A study of horses grazing on teff pasture found that they had similar total amino acid levels in their blood compared to horses grazing other types of forages. [19]

However, blood levels of threonine were lower in horses grazing on teff than mixed cool-season grasses. [19] Horses in heavy work or with higher protein requirements may benefit from a high-quality protein supplement while consuming teff hay.

NSC Levels Range Significantly

Teff typically has low NSC levels of 10% or less. However, NSC levels can increase as the plant matures and stores more starch.

Environmental conditions while growing and during harvest can impact NSC concentrations of teff hay. Submitting a forage sample for analysis is the best way to determine any forage’s sugar and starch content.

Low in Trace Minerals and Vitamins

Teff contains low levels of certain trace minerals and vitamins. One study found that teff hay failed to meet copper or zinc requirements for horses. [5]

Horses consuming teff hay should be fed a high