Careful feeding rearing heifers can boost results

Published 28 May 10

Dairy farmers could save £1000s by improving their heifer rearing system, according to experts speaking at a series of recent DairyCo meetings across the South West.

With careful feeding heifers can calve at 22-24 months instead of the typical 33 months, resulting in fewer calving difficulties, lower mortality over five years and significantly higher milk yields over the same time, says Chris Coxon, South West extension officer at DairyCo.

"A lot of people say they can't calve their heifers at two years old because they are not big enough - but it is all down to feeding them right. You need to get the calves off to a good start and feed them properly when young, as that is when the feed conversion efficiencies are at their best. Feed conversion is very high at 1.25:1 in early life and we need to be making the most of that."

Newborn calves should receive 10% of their bodyweight in colostrum in the first 24 hours, with half of that in their first six hours of life, says Mr Coxon. For a 40kg calf that equates to two litres of milk, or 15 minutes of suckling, ideally in the first two hours of life. "Only 40% of calves achieve this unaided, so farmers need to be there to assist both cow and calf."

When feeding milk powder farmers should use a teat system to start with, and opt for an enhanced growth, high quality powder. This provides 18% fat and 26% protein instead a typical formula of 20% of each. It should be diluted at a rate of 15% rather than 10%, and with daily intakes of six litres the calf should consume 900g of powder per day, compared to just 500g on a normal system. Combined with ad-lib creep feed, calves can be expected to put on 0.8kg of weight per day over the first six weeks - 0.2kg/day more than average.

"It is also really important to provide good quality 18% protein concentrate and fresh water from day one, to help rumen development," says Mr Coxon. "Roughage, preferably in the form of straw, should be provided in racks to minimise intakes of contaminated feed."

Although an enhanced feeding regime costs more in the short term, bringing heifers into heat earlier and calving at 24 months means they start milking and paying back their rearing costs more quickly. Rearing heifers to calve at 33 months in a very low input autumn-calving herd costs a net average £1211 per head, while heifers calving at 22 months on a high input system have already paid back their rearing costs by £68 after a further 11 months have passed, he adds.

In addition, younger calving heifers tend to have fewer calving difficulties, live longer and produce more milk. A five-year study by DairyCo showed that only 17% of those calving at 22-23 months, at a pre-calving weight of 591kg, required calving assistance, compared to 67% of those calving at 32-26 months.

"Ideally, producers should aim to bull heifers when they are 70% grown at the withers and 50-60% of their adult weight," says Mr Coxon. "That way they will be easier to get into calf, and be nicely grown but not overweight by the time they calve. Older, fatter heifers can suffer from fertility and calving difficulties, as well as metabolic problems after calving."

Some 86% of the younger calving group were still alive at five years of age, against just 33% of the older group, he adds. "The younger cows spent 48% of their first five years in milk, resulting in a five-year yield of 25,031 litres. That compared to 18% of the older group, which had a five-year yield of just 8029 litres. The more time that a cow spends in milk, the better the income for the business. Calving heifers younger also has clear health and welfare benefits, which has to be good for the entire industry."

For more information on heifer rearing, order your free feeding+ manual from DairyCo by calling 024 76 478702or visit www.dairyco.org.uk