Intakes rise when tasty silage replaces straw
Poor quality straw, and the
need to improve
encouraged one Leics milk
producer to feed silage to
Jessica Buss reports
SWITCHING from straw to silage-based rations has improved heifer performance for Roy Eggleston of Bridge Farm, Long Clawson.
His high merit heifers are now achieving target growth rates and coming bulling well to calve at two-years-old on diets which include some grass silage. But by feeding some straw, rather than offering an all-silage diet, he can also prevent heifers becoming too fat.
Mr Eggleston rears 80-90 heifers a year, at 178ha (440-acre) Bridge Farm, for replacements for his 130-cow milking herd and for sale as calved heifers. They must grow well to calve at more than 600kg between 22 and 26 months, and are weighed to ensure they have reached 350kg before bulling.
Mr Eggleston also expects heifers to peak at 40 litres – he seeks high outputs, with cows averaging 10,100 litres, and heifers 8330 litres.
For about five years heifers -admittedly of lower genetic merit – grew adequately on straw and maize gluten, which replaced an all-silage diet on which heifers became too fat. Switching to straw-based rations for heifers also released extra silage for the cows.
But last winter, Mr Eggleston and his independent nutrition consultant Paul Findley were disappointed to find that heifers failed to achieve target growth rates of 0.6-0.65kg a day for young calves and 0.9kg a day for older heifers.
"Heifer diets were dry and boring and we felt silage would make it more interesting, encouraging intakes," says Mr Eggleston.
Although grass silage supply was limited, they found that by offering heifers 1.5kg DM a head of grass silage, in a total mixed ration with less concentrate, performance improved dramatically.
Herdsman Andrew Spicer also noticed an improvement in the heifers. Their yields have increased by 700 litres in a year, they have greater body capacity and animals are bigger in the rib – though some of these benefits are assisted by improved genetics, he adds.
"When feed is always in front of heifers, stock are more content and there is no racing about, reducing stress," adds Mr Eggleston. This also allows smaller animals to compete well, when the age range of a group is about three to four months.
This year good quality straw is difficult to buy, it is dusty and smashed up, but luckily more silage is available, says Mr Findley.
"Older heifers that are bulling or in-calf are receiving 4.5kg DM of first cut grass silage, 2kg DM of wheat straw and 2.5kg of UK-produced maize gluten with 100g of minerals." They are also offered extra straw, but eat little of it.
"When bulling heifers come in from grass, they typically miss one or more heats, but since putting more silage in the diet, nearly all continued bulling normally after housing this year," says Mr Spicer.
The youngest heifers also began the winter on silage and straw, but did not thrive on the poor quality straw. Their ration now consists of high DM ad-lib square bale silage, and 2kg of maize gluten. This has seen growth rates and condition improve, adds Mr Findley.
As well as improved performance, purchased feed costs have fallen. Heifers on straw diets had been offered up to 4kg a day of maize gluten, but by feeding more silage concentrate use has halved.
Silage makes the heifer diet more interesting, encouraging intakes… Roy Eggleston.
SILAGE FOR HEIFERS
• Straw quality is poor this year.
• Animals meet target growth rate.
• Silage allows cake reductions.
• Fertility better, less stress.
Heifers achieve target growth rates and are bulling well on a mixed diet of grass silage, straw and maize gluten, say herdsman Andrew Spicer (right) pictured with Paul Findley. With more silage in the diet its also cheaper.