Improving the health producing attributes of meat and milk could be as simple as modifying the diet of New Zealand’s sheep.

AgResearch scientists believe enhancing the fatty acids in ryegrass – the mainstay of sheep fodder in New Zealand – could improve the health-giving benefits of the sheep eating the grass.

AgResearch Grasslands scientists have shown the potential for introducing fatty acids into a sheep’s diet, and are now working on ways to deliver more of the desirable fatty acids in forage.

Both saturated and unsaturated fatty acids are found naturally in meat and milk.  Food containing some types of unsaturated fatty acids is considered good for humans because it reduces cholesterol, and offers protection against heart disease and strokes. 

Anything that can be done to boost the ratio of unsaturated fatty acid levels in meat in a natural and sustainable way will therefore not only improve the health of meat consumers, but also offer the New Zealand farming industry a valuable opportunity to grow the type of sheep that produce products demanded by consumers world-wide.

AgResearch now know changing the diet of sheep changes the fatty acids produced in their milk and meat.   Not only that, their recent research showed an increase in the good fatty acids actually improved productivity on-farm.

The Grasslands scientists did this by artificially increasing polyunsaturated fats through dosing lambs with vegetable oils, which showed up in the carcass quality of animals in the trial.  What’s also really interesting is that the sheep had better feed efficiency, performing the same on 16 percent less feed – a finding which could ultimately mean more animals to the hectare and much greater on-farm productivity.

AgResearch is not advocating dosing lambs with polyunsaturated vegetable oils; rather AgResearch Grasslands pasture specialist Dr Gerald Cosgrove has proved modifying diet can influence fatty acids, and this opens a whole new and exciting area of research.

“With the dependence on pasture-based systems for animal production in New Zealand altering the fatty acid profile in grass may be the most economic way to change the fatty acid characteristics of the meat or milk produced by New Zealand ruminants,” Dr Cosgrove said.

The next stage for the science team is to see how fatty acid levels could be boosted in ryegrass or other forage species, either through conventional or molecular breeding techniques.   If the scientists were able to successfully modify pasture it would then be trialled on sheep to test not only its levels of fatty acids, but also on animal growth and productivity.