26 July 2002

Liver boost lifts yield

By Jeremy Hunt

North-west correspondent

MILK yields have increased by 1000 litres a cow in a Lancashire college herd fed a dietary additive designed to enhance liver function.

The Nu-Tec additive, LiFT has been on trial at Myerscough College, Lancs, where it was included in cow diets for 21-days pre-calving and for the first 100 days of lactation at a cost of £21 a cow, but the increase in milk income is worth £165.

Two evenly matched groups of cows were involved. Both were fed grass silage and a dry cow ration in the pre-calving period, then a grass and maize silage mix plus compound during lactation. One of the groups received the additive, says Sion Richards of Provimis Nu-Tec division, who carried out the trial in conjunction with Pye Farm Feeds.

In the Myerscough trial additive-fed cows gave an extra two litres a day in the week after calving, followed by 4.3 litres at six weeks into lactation which continued for another six weeks. The rate of inclusion was 50g a day during the dry period increasing to 100g a day post-calving.

"Yields were 3.4 litres a day higher in the additive fed group for the first 100 days in-milk, with increased yield continuing throughout the 305-day lactation," says Mr Richards. Results also showed lower somatic cell counts in cows fed LiFT and improved conception rates. Average days to first service for treated cows was 80 compared with 85 days for the control group.

The additive is said to help optimise the livers natural resources and assist it in overcoming areas of metabolic weakness, therefore increasing its efficiency. It helps to free metabolisable fatty acids in the liver, decrease ketones and transport fat from the liver.

Other data collected from the trial showed that half the cows fed LiFT achieved more than 9000 litres and a third of them gave more than 10,000 litres. But Myerscough agriculture programme leader Allan Nickson didnt see any major difference in body condition despite higher production from treated cows.

"We believe the 12-month trial has proved conclusively that LiFT is an ideal feed additive for high performance cows, while remaining mindful of the welfare implications of pushing for higher yields," says Mr Nickson.

"I see LiFT as part of the technical armoury of todays producer, where extra production can be gained by natural methods, based on improving cow efficiency."

John Long of Lancaster-based Pye Farm Feeds adds that we are at last seeing a feed additive improve the function of the liver with substantial benefits in yield. "But its important to stress that this product is not aimed at pushing cows beyond their capabilities. All that is happening is that the liver is being made to function efficiently, allowing cows to express their full milking potential, naturally." &#42

Despite higher yields using LIFT in cow feed, body condition score remained similar in treated and untreated cows, says Allan Nickson.

&#8226 Boosts yield through lactation.

&#8226 Cell counts reduced.

&#8226 Better fertility results.