Frequently Asked Questions

What is “High Sugar Grass”?

Aber® High Sugar Grass (HSG) is the term given to new ryegrass varieties that have been bred specifically to contain very high levels of water soluble carbohydrate (sugars). These have been bred by IBERS, the Institute of Biological, Environmental and Rural Sciences and carry the prefix “Aber”, which denotes the origin and authenticity of the breeding. However, not all “Aber” varieties are HSG varieties.

Why has Aber HSG been developed?

Breeding for increased quality, such as high sugar content to improve the efficiency of rumen function, is the next logical stage in the development of new grass varieties in the 21st century. IBERS’ scientists discovered more than two decades ago that livestock grazing grass with a high sugar content produced more meat and milk. Forage breeders at IBERS have since worked to develop new varieties with this valuable quality trait, combined with other important agronomic characteristics such as high yield, persistency and disease resistance.

How does Aber HSG work?

Aber HSG varieties provide extra energy (sugar) for the rumen microbes, which allows them to utilise more of the available protein from grass and clover. The proportion of this protein used in meat or milk production is increased, and the amount lost via dung and urine is reduced.

Is Aber High Sugar Grass a GMO?

No. Aber HSG varieties have been developed using traditional grass breeding techniques.

What are the main economic benefits of Aber HSG for the livestock farmer?

Extensive research has shown that HSG varieties produce measurable performance benefits for dairy, beef and lamb producers, such as:

  • Cows fed HSG produced 10% more autumn milksolids than cows fed standard ryegrass1
  • Lambs grazing HSG finished 17% faster, with 19% heavier carcass weights than lambs grazing standard ryegrass2
  • Overseas trials have shown a 20% higher daily liveweight gain for beef cattle when fed or grazed on HSG3

Are there any other significant benefits?

There are significant environmental benefits, due to more efficient use of feed nitrogen and a reduction in the nitrogen excreted into the environment. This is highly significant in the context of future farming practices. Nitrogen emissions by ruminant livestock are considerable, so any technology that can reduce overall levels is increasingly important.

Are the benefits of Aber HSG retained when ensiling?

On–going research is showing that the higher levels of water soluble carbohydrate in Aber HSG varieties can lead to a higher feed value silage, particularly where an effective inoculant is used to encourage an efficient fermentation. An effective additive will promote a rapid and efficient fermentation, which drops the pH quickly and maximises the amount of sugar retained in the silage.

How much higher is the sugar content of an Aber HSG variety, compared with other grass varieties?

The level of water soluble carbohydrate in all grass varieties varies according to the seasonal conditions and the growth period. Independent trial results have proven Aber HSG’s deliver up to 17% more water soluble carbohydrates than standard diploid perennial ryegrass4. As well as more sugar, research has shown Aber HSG’s to have lower levels of fibre than control ryegrasses and 15% greater lipid (wax, oil and fat) content4, which acts as another source of energy.

1Cosgrove, G. P.; Burke, J.L.; Death, A.F.; Hickey, M.J.; Pacheco, D.; Lane, G.A. 2007. Ryegrasses with increased water soluble carbohydrate: evaluating the potential for grazing dairy cows in New Zealand. Proceedings of the New Zealand Grassland Association 69: 179–185.

2Craig, H.; Fennessy, P.; McLean, N.; Chuah, J.; Campbell, A. 2014. High Sugar Ryegrass. Report on project prepared for Alliance Group Limited and Germinal Seeds Limited.

3British Seed Houses. 2012. Aber High Sugar Grasses trial work was conducted at the Institute of Biological, Environmental and Rural Sciences (IBERS) and on commercial farms.

4Jonker, A.; Molano, G.; Sandoval, E.; Taylor, P.; Antwi, C.; Cosgrove, G.P. 2014. Methane emissions by sheep offered high–sugar or conventional perennial ryegrass at two allowances. Proceedings of the New Zealand Society of Animal Production 74: 145–147.