Growing and harvesting factors affecting the carbohydrate profile of teff grass (Eragrostis tef) for horses

Natalie Suzanne Shaw

The demand for low non-structural carbohydrate (NSC) horse hay is growing due to increased prevalence of equine metabolic disease and the associated risk of laminitis. Teff (Eragrostis teff Zucc.) has been identified as a potential forage for horses that require low NSC diets, but growing and harvesting techniques that reduce NSC and increase quality must be refined in order to improve availability, consistency, and horse health outcomes. Eight teff production strategies and environmental factors were examined over three years in the Pacific Northwest as to their effects on the ethanol soluble carbohydrates (ESC), water-soluble carbohydrates (WSC), acid detergent fiber (ADF), neutral detergent fiber (NDF, lignin, crude protein, yield and digestible energy of teff hay. Statistical analysis revealed significant effects of nitrogen fertilization, stage of maturity, cutting number, variety, and time of day harvested. Cutting height, diurnal temperature fluctuations on harvest day, and growing degree days had no effect on the NSC of teff grass harvested for hay. Generally, as nitrogen fertilization increased NSC decreased (P<0.0001) while advancing stages of maturity increased NSC (P<0.0001). Second cutting teff across multiple studies showed lower NSC values than first cutting (P<0.0001). In the teff v variety trial, ‘Dessie’ had the lowest WSC values (5.37%) while ‘Excalibur’ had the highest (6.89%; P<0.0001) indicating selection potential for lower NSC teff. The Time of Day harvested showed PM cuttings with higher NSC values in all years (P<0.0001), but no variation in AM and NOON which increases the window of opportunity for growers. Yield increased from 3,922 kg ha-1 at boot stage to 4,416 kg ha-1 at late heading stage of maturity. Digestible energy increased with higher levels of nitrogen application (P<0.0001), decreased with advancing stage of maturity (P<0.0001), and was highest for first compared to second cutting (P<0.0001). In summary, for teff to produce the highest yield, best quality, and lowest NSC the crop should be fertilized at 67.39 kg N ha-1 before each cutting, harvested before noon, and at early heading stage of maturity. Results from these studies illustrate teff’s unique ability to meet the nutritional needs of horses while diversifying crop rotations for hay growers.

Growing and harvesting factors affecting the carbohydrate profile of teff grass (Eragrostis tef) for horses

Files and links (1)

Abstract

Metrics

Details