12 May 1995

INOCULANTS

"INOCULANT" is an umbrella term used to describe products that apply bacteria to grass at ensiling, according to Dr Keady.

In 11 Hillsborough experiments in which different inoculants were evaluated using herbages of low dry matter and sugar content, inoculant treatment increased silage intake and animal performance with dairy cows, as measured by milk yield, by 7% from 19.9kg to 21.2kg a cow a day.

Other studies there have shown an effective inoculant, under conditions where the untreated silage was poorly preserved, raised beef performance, measured by daily carcass gain. The lift was from 0.46kg to 0.52kg a day, similar to that obtained from a well-preserved formic acid-treated silage.

"The main aim is to apply the inoculant at the recommended level," says Dr Keady. "Aim for 1m colony forming units (bacteria) a gram of herbage ensiled.

"You cant judge an inoculant by its bacterial composition. It is important to have evidence from positive trial results from independent research centres, where animal performance was assessed under similar conditions in which the product will be used." &#42