Review systems for calf rearing to achieve growth
Dairy farmers breeding their own replacements should review their calf rearing systems once a year, according to Volac International’s Maggie Gould.
“Great investments have been made in cattle genetics during the last decade, yet calf feeding and management practices have remained largely unchanged. This may in turn, be preventing animals from achieving their true genetic potential,” she says.
The continuing use of traditional feeding systems was reflected in a survey of 297 dairy producers carried out by Volac earlier this year – see graph.
“We were surprised to find that over 80 per cent of farmers continue to use bucket systems,” says Mrs Gould. “While traditional calf rearing systems can be cost-effective, the practice of feeding once or twice a day, and limiting calf milk replacer intake to weaning, results in restricted early growth and requires calves to catch up later.
“This practice has a low cost per kilo daily liveweight gain to weaning, however it also leads to low liveweight gains in the first few months and may not be the most cost effective solution overall.
“This is particularly important when rearing a high genetic merit calf, which must be viewed from the moment it is born as the high performing cow of the future. Build a feeding system and management plan to maximise its performance potential.”
Farmers have an array of calf rearing systems to choose from, says Trevor Hamilton, Clyde Veterinary Group (see panel below).
“It's a case of selecting the system which fits your own bespoke action plan for your farm,” he says.
“There are two basic ways of delivering milk to a calf, either through a teat or straight from a bucket, which requires training the calf to properly suckle milk.
“There are benefits of teaching a calf to suck milk, as it will stimulate the oesophageal groove reflex in the stomach, ensuring the milk passes straight into the abomasum, or true stomach. If calves do not suckle, milk can enter the rumen, where it is not properly digested, and you'll find yourself with so-called ‘rumenal drinkers' which fail to thrive until weaned.”
Mr Hamilton says when reviewing systems, research all possibilities and discuss requirements with vets and equipment suppliers.
Pros and cons of different feeding systems
Feeding can be controlled very precisely and measured amounts given in one or more daily feeds; problems evident if feeds not taken.
Exposure to infections vastly reduced as mixing is minimal.
Labour intensive and requires a large area for small numbers.
Socialising is limited as
contact is normally over a gate
or solid partition.
Exercise is limited. Feed is often restricted, which can limit growth rates.
Group rearing (milkbars and ad-lib systems)
Feeding can be in troughs at defined intervals, often following on from individual pens, or from a machine where feeding is on an ad-lib basis rather than at set times. This matches the calf's natural feeding pattern more closely.
Calves can socialise more easily and exercise freely.
Infection spreads more easily. If calves become ill they require individual penning.
Hard to check individual calves are feeding as they should (unless transponder collars are used).
Keeping feeding machines clean.
Difficult to control individual intake, as calves can feed as often as they like, sometimes leading to scours and making weaning harder.
Group Rearing with programmed feeding (computerised feeders)
Collars or eartags identify individual calves and control feeding precisely, prevent overfeeding and bring attention to calves that stop feeding.
Feeding machines need to be kept clean to limit infection spread and stop tubes getting blocked.