Adding ative live yeast Vistacell can improve rumen function in grazing cows, says supplier AB Vista.
Pointing to a farm-scale study using a herd of 300 robot-milked cows in Waikato, AB Vista says it can improve dry matter digestibility by 30%, lift average daily milk yields by 2.1L/cow and increase cow liveweight (LW) by up to 20kg in just five weeks.
The Waikato herd contained a mix of autumn and spring calvers, with all cows also having access to a mixed ration of grass silage, maize silage, straw and concentrates, plus an extra 3-6kg/day of concentrates fed during milking depending on yield.
“This is the first time we’ve had access to individual cow data on such a large scale, and the results are relevant to any herd where grazing accounts for a significant portion of the daily feed intake,” says Dr Nicola Walker, AB Vista’s ruminant product development manager.
“When supplemented with additional feeding, grazed grass is now known to pose a significant risk of inducing low rumen pH and sub-acute ruminal acidosis (SARA), both of which can significantly compromise fibre digestion and feed conversion efficiency.”
The impact of the yeast was confirmed when removed after an initial five week period. Milk yields dropped 1-2L/cow over the following two weeks, with cows losing an average of 5-10kg LW as they attempted to maintain production by drawing on body reserves.
“Manure sieving results taken throughout the trial highlighted the huge impact on fibre digestion,” adds Walker. “Dry matter digestibility increased 30% following addition of Vistacell to the ration, with a similar reduction when it was removed.
“That represents a lot of extra nutrients that can go into producing milk or rebuilding body reserves, and would otherwise be lost in the manure.”
AB Vista is a global supplier of micro-ingredients for the animal feed industry.
www.abvista.com