A new infrared test that measures the quality of different hays will help farmers to determine how much feed an animal will eat.

CSIRO's Near Infrared Reflectance Spectroscopy (NIRS) is the subject of patents in a number of countries including the United States, Australia, Europe and Japan.

According to Dr David Henry, Project Leader at CSIRO Livestock Industries, the objective measurement of the 'toughness' or shear energy of hay quality using NIRS is a world first.

"In the fodder industry, there is a large reliance on subjective assessments to determine which is the better hay," he says.

"Many producers look at the hay's colour, texture and taste it for sweetness. However, people vary in their interpretation for a variety of reasons and while the current chemical analyses used can estimate the nutritive value of the feed, they cannot predict feed intake."

At CSIRO Livestock Industries, forty years of research into what drives feed intake culminated in the development in 1993 of a 'shear energy' measurement. This measurement reflects the time it takes an animal to break down feed into small particle sizes that can be easily digested. The higher a plant's shear energy measurement (or toughness), the less an animal will eat when offered the feed in a voluntary situation.

"What we've now done is develop the use of NIR to measure that shear energy," Dr Henry says. "The beauty of NIRS is that it is inexpensive, rapid and accurate."

Around the world, NIRS is already used for forage or feed testing to measure fibre and sugar content to help predict animal performance. Dr Henry envisages NIR measurement of the shear energy character of fibre as an additional test which can rapidly and accurately measure forage quality. In many cases, standard industry laboratory equipment can be used and existing samples recalibrated for shear energy or toughness.

Much of CSIRO's research has focussed on the oaten hay industry, where Australia has a large export hay market to Japan, South East Asia and the Middle East.

"This market is very competitive and you need an objective measurement of quality," Dr Henry says. "There is wide recognition of the need to trade fodder on the basis of its feeding value, rather than on traditional subjective criteria, like colour, aroma and texture."

"What we have found is that there is an extremely wide variation in all forage quality characters from season to season, region to region, across varieties of forage species and differing agronomic practices," he says.

"We feel we have a robust and accurate method of measuring quality, based on the oaten hay industry, and would like to make that test widely available."

Dr Henry believes there are real field applications for the NIRS technology to measure feed quality. A NIR measurement of shear energy could be incorporated into standard tests for other characteristics, such as fibre and carbohydrate.

"Incorporation of the shear energy measurement into NIR laboratory testing is a relatively simple task," Dr Henry said.

"In the future, we might see a scenario where a NIR machine is fitted to a hay baler. As the farmer is going across his paddock and baling his hay, he gets a measurement of feed quality across the entire paddock. That hay then goes to the processor or export company, where there is capacity for a NIR machine to continuously measure the quality of hay moving along the conveyor belts."

When coupled to a Global Positioning System (GPS) this could create yield maps and other data for precision agriculture. In-field measurement will allow better quality control, traceability and feed security.

More information:

Dr David Henry, CSIRO Livestock Industries 08 9333 6689, 0429 088 112

Anton Coppens, CSIRO Livestock Industries 08 9333 6684