Net Feed Intake Explained

WHY IS NFI IMPORTANT?

• Animals with negative NFI require less feed to produce the same level of production.
• Under pasture systems you can have higher stocking rates but still meet animal requirements for growth.
• It is a moderately heritable trait (39%) which means that progress in improving the trait can be made via selection.

FEED EFFICIENCY IS THE MOSTIMPORTANT PRODUCTION TRAIT

Breedplan has adopted the Feed Efficiency measure, NET FEED INTAKE(NFI) and in simple terms, this is the amount of actual feed an animaleats on a daily basis, under or over, what is expected for its weight and gain. This measure has the important benefit of being independent of the animal’s weight and gain.

With NFI, more efficient cattle can be found within any desired cattlerange and selection will not increase mature size.

Reporting Net Feed Intake EBV’s…

NFI EBV’s are reported as kg of feed eaten per day. Like most EBV’s theycan be + or – relative to the breed average. The more negative the NFI EBV, the less feed eaten and the more efficient the animal. An animalthat eats more than expected will have a positive EBV.

How is NFI measured…

The initial measurements were based on measuring individual animal feedintakes and weight gains. In 2004, researchers at AGBU found a positive relationship between Insulin – like Growth Factor (IGF-1) and NFI. IGF-1 is a circulating blood hormone. It is heritable and correlated to NFI. A blood test determines the level of IGF-1 in a particular animal, which is of immense value to the seedstock producer.

Selecting for Net Feed Intake…

Selecting for NFI will reduce feed intake without compromising body weight or performance.

Correlation with other traits, particularly meat quality research indicatesthere is no effect on other traits, when selecting for NFI apart from asmall link with leanness (cattle with lower NFI EBV’s being slightly leaner). The correlation is however low, and can therefore be managed by selectingon both traits.