'Super-grass' aims to boost milk production

NZPA - Stuff, New Zealand

02/03/2010

Researchers planning on launching a genetically-engineered "super-grass" by 2013 claim cows grazing on it will produce up to 20 percent more milk.

The GE ryegrass - being developed in Australia for New Zealand seed company PGG Wrightson - has potential to make a huge difference to agriculture, according to the chief executive of the Australia's Molecular Plant Breeding Cooperative Research Centre (MPBCRC), Glenn Tong.

Existing dairy farming pasture-grasses are mainly perennial ryegrass and tall fescue, but the perennial ryegrass grows best in temperate areas that are becoming warmer with climate change.

Mr Tong told the ABC that the technology works to increase the carbohydrates or energy molecules in the grass, and the fodder will also be more digestible than existing ryegrass so the sheep and cows can access those energy molecules more easily.

The Australian researchers working with PGG Wrightson Genomics are also developing a GE grass to reduce the amount of methane given off by livestock, blamed for contributing to global warming.

The scientists at Gramina - the joint biotech venture by New Zealand rural services group PGG Wrightson Genomics and the MPBCRC - are also developing a grass that will not only reduce the amount of methane cows burp up when chewing the cud, but also grow in warmer climates.

This means that farmers may be able to maintain dairy herds' productivity and profitability in the face of a global warming, while reducing their greenhouse gas emissions.

Methane makes up 14.3 percent of humanity's contribution to global warming and nearly half of New Zealand's.

Ruminant livestock such as cattle and sheep produce methane generated by the micro-organisms in their gut that help them break down cellulose in grass.

Gramina has been using "sense suppression" technology to prevent the expression of an enzyme - making the grass more easily digested.

The Gramina partnership and PGG Wrightson Ltd, the parent company of PGG Wrightson Genomics, have so far been given over $NZ5 million in funding from New Zealand taxpayers.

Wrightson has previously predicted global markets will be ready for milk and meat grown on genetically engineered pastures by the time it releases its GE ryegrass, even though some consumers may object to dairy products and meat reared on GE pastures.

By the time commercial seed was available there would be consumers willing to accept produce from animals fed on GE grass, it said.

Importantly, the grasses would not be transgenic - containing genetic codes from other species - but would have some of their existing genes either switched off, or boosted in terms of proteins they produced - a research path recently promoted by the biotechnology sector as "cisgenic".

Ad Feedback In August 2003, former Environment Minister Marian Hobbs said that - hypothetically speaking - if a state science company wanted to apply to release GE ryegrass without conditions "I'm pretty sure that wouldn't get through at the moment".

The Environmental Risk Management Authority (Erma) had to take into account the national economic benefit implicit in any approval of GE organisms, she said. One problem would be perceptions GE pasture plants might raise overseas of key export sectors such as dairying.

"If you're doing things that were to go immediately into the food chain in New Zealand, that would begin to raise some issues around timing and confidence and risk and food safety," she said.

In a separate project, NZ Agriseeds Ltd scientists are working on producing temperate pasture grasses with enhanced heat-stress tolerance, water efficiency and increased pest resistance.

Giant dairy cooperative Fonterra initially joined with a United States company, Orion Genomics, to identify the complete gene set of ryegrass, in privately-funded research.

Since then Fonterra has been part of a "pastoral genomics consortium" with AgResearch, Meat and Wool NZ, DairyNZ and the Deer Industry New Zealand, set up to develop a functional genome for clover.

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