A guide to the award-winning Aber HSG range


Aber High Sugar Grass varieties (Aber HSG) are identifiable by the ‘Aber’ prefix and feature strongly in the Recommended Grass & Clover Lists. They will perform outstandingly in high-performance grass mixtures for grazing and cutting, for all ruminant species.

Quality forage options with Aber HSG grass seed

These high sugar ryegrasses are bred at the Institute of Biological, Environmental and Rural Sciences (IBERS) Aberystwyth University, where the ambition to achieve nutritional quality – alongside dry matter yield and strong agronomic performance – was first conceived.

The IBERS programme links grass breeding with animal performance and continues to produce new and improved varieties, year on year.

Average water soluble carbohydrate level

Data from IBERS' long-term trial: Average WSC over five years, seven cuts per year, three HSG varieties (AberDart, AberStar, AberMagic) and two normal varieties (Premium, Talbot).

Aber HSG – the key difference

  • Contains higher levels of water-soluble carbohydrate (WSC or sugar) than conventional ryegrasses
  • Provides increased readily available energy to feed fibre-digesting rumen microbes
  • More active rumen microbes convert more forage protein into milk or meat, with less being wasted

Aber HSG – performance benefit

  • Higher dry matter yields from grazing or cutting
  • Improved dry matter (DM) intakes from enhanced fibre digestion and greater palatability
  • Higher milk yields or growth rates resulting from more efficient forage protein conversion

Aber HSG – environmental benefit

  • In zero-grazing trials involving early, mid and late lactation dairy cows, the amount of feed nitrogen lost in urine was reduced by up to 24% in animals fed HSG
  • Reduced nitrogenous waste resulting from more efficient forage protein conversion
  • Lower emissions of ammonia

Trial Results

Aber HSG for milk production

Accumulated studies at IBERS and on commercial dairy farms have shown that grass protein is used more efficiently when extra energy is provided by feeding HSG varieties.

  • 6% more milk per cow over a grazing season
  • DM intakes increased by 2 kg/cow/day
  • 3% improvement in diet digestibility

Aber HSG for beef production

Grazing trials and companion zero-grazing trials at IBERS have shown that when extra energy is provided to beef cattle by feeding our HSG varieties, grass protein is used more efficiently, and performance is enhanced.

  • DM intakes increased by 25%
  • 20% high liveweight gains
  • Slaughter weights reached earlier

Aber HSG for lamb production

Performance in lambs grazing this ryegrass was higher in upland and lowland situations.

  • Higher forage intakes
  • 20% higher liveweight gains
  • 20% higher sward carrying capacity

High Sugar Grass reduces environmental impact

Reductions in nitrate leaching (4-6%) and lower ammonia losses to the atmosphere (7-11%) contribute to a significantly lower carbon footprint when cows graze Aber HSG swards, according to the CLEANER COWS* modelling study. When combined with improved manure management the carbon footprint per litre of milk production can be as much as 40% lower.

* Soteriades, A., Gonzalez-Mejia, A., Styles, D., Foskolos, A., Moorby, J. and Gibbons, J. (2018). Effects of high-sugar grasses and improved manure management on the environmental footprint of milk production at farm level. Journal of Cleaner Production. 202 (1), 1241-1252.

The science behind Aber High Sugar Grass

This cutting-edge grass range has been developed to remedy the imbalance between readily available energy and protein.

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