2 August 2002

ACCURATE FORAGE INTAKE PREDICTION WITH SILAGE VALUE

WITH many producers receiving their analysis results from first-cut silage, a new silage analysis value will allow forage intake predictions to be more accurate this winter.

When formulating a new cow ration, a good estimate of how much will be eaten is essential, says independent nutritionist Geoff Hughes. "The new Feed into Milk (FiM) system uses a new equation to predict dry matter intake, which should prove more accurate than existing methods.

Where intakes are overestimated, animals receive insufficient nutrients, limiting milk output, while underestimating intakes lead to over expensive rations. To address this, the FiM system includes a Silage Intake Potential value to ensure that the correct silage intake is predicted.

Typical values of SIP are about 120 for fresh grass, 90 for high acid silage and 105 for low acid silage. The higher the value, the greater the intake potential of silage, explains Mr Hughes.

"However, predicted intake is a baseline level which should be regarded as a minimum target. Herds fed mixed rations should achieve a higher intake than those feeding silage plus concentrates in the parlour."

Mr Hughes believes when adjusting for individual farm conditions, higher intakes than predicted may be achieved. This difference depends on genetics, ration presentation and whether trough space is restricting cow access. &#42


England Northern

and Wales* Ireland

Mean 103 90

Range 49-154 70-130

* Frank Wright silage analysis