7 March 1997

Still more profits from maize silage

Maize Growers Association members heard the latest research results at its annual conference last week. Jessica Buss reports

MAIZE growers achieve £31 a cow more profit on average than those feeding grass silage alone – and top growers double this figure. But the extra earnings still fall short of the potential increase predicted by research into mixed forage diets.

This was the finding of a recent Genus, MDC and MGA-funded survey, reported at the MGA conference at Harper Adams College, Shropshire.

The potential of maize for increasing profit was £181 to £232 a cow, depending on the proportion fed, according to CEDAR, University of Reading studies. This was achieved through higher dry matter intakes, and increased milk and protein yields.

High maize feeders offering 60% in this survey produced 236 litres a cow more than low maize feeders providing 30% but used 64kg more concentrate – resulting in 55 litres less from forage.

Producers could be missing out on the full potential of maize due to poor feeding efficiency and agronomy, said Genus Manage-ments Neil Adams who compiled the survey of 60 grass silage only and 100 maize growing farms.

Maize feeders sold an extra 139 litres a cow compared with grass silage only feeders and 124 of these extra litres came from home grown forage, so concentrate use was similar. And, milk prices suggested the maize diets gave no general improvement in milk constituents.

Failing to realise the potential of maize could be caused by lack of experience, for only 28% had grown the crop for more than four years, claimed Mr Adams. There were many factors that could limit performance of maize such as limited forage stocks that were not assessed in the study.

One factor that could affect the efficiency of maize use was spread calving patterns.

"Cows respond best to maize fed in early lactation so consider feeding them a higher level of maize than later lactation cows," said Mr Adams. Genetic variations and herd health may also reduce the response seen.

Poor diet formulation was also suspected to be at fault. "To assist ration formulation an accurate analysis is needed. Yet a quarter of producers had no maize silage analysis. And, of those that had an analysis, a third showed energy levels below 10.6ME – bringing agronomy and variety choice into question."

When it came to feeding maize, many systems had been changed but expensive feeder wagons only increased gross margin a cow by £31 compared with simpler feeding systems.

"There is also confusion over concentrate allocation with over 60% of farms feeding to yield," he said. This meant that instead of increasing yield from forage, you increased yield from concentrate.

The CEDAR trial showed flat rate feeding achieved 100 litres a cow more from 100kg less concentrate. However, this was when feeding ad-lib diets which needed adequate feeding space and enough feed offered each day. In the trials 10% extra feed was offered – for the last feed left in troughs was hardest to eat. But do not allow stale feed to build up, he added.

The response to extra concentrates in both the CEDAR and Genus studies was 0.8 litres/kg. And, in the Genus study offering an extra 716kg of concentrate resulted in only 585 litres, increasing margin a cow by £68. Given that quota was limiting, warned Mr Adams it is unlikely these extra litres produced from concentrate were profitable.


&#8226 Increase the proportion fed to early lactation cows.

&#8226 Formulate diets correctly using an analysis.

&#8226 High levels of concentrates may be unprofitable.

Neil Adams of Genus Management:"Cows respond best to maize fed in early lactation."


&#8226 Increase the proportion fed to early lactation cows.

&#8226 Formulate diets correctly using an analysis.

&#8226 High levels of concentrates may be unprofitable.