background image
APRIL 2019
Education
www.irishfarmersmonthly.com
More than half the replacement heifer calves being reared
on UK commercial dairy units could be growing too slowly
to hit targets for optimal health and lifetime productivity.
New practical research, carried out by a team from the
Royal Veterinary College (RVC), has found that 70% of
nearly 500 pre-weaned calves on 11 dairy farms in south east
England had growth rates below the recommended 0.7kg
per day and of these 20% grew at less than 0.5kg per day.
More than 70% of the heifers studied were pure Holsteins.
The amount of milk solids fed to individual calves on the
11 farms over their first 63 days of life ranged from 16kg to
56kg. Weaning age varied between 37 and 97 days.
The work was co-funded by the Biotechnical and Biological
Sciences Research Council (BBSRC) and Volac. Research
scientists hope the study findings will encourage more dairy
farmers to feed calves more milk during the pre-weaned
phase and to monitor growth rates more closely.
According to Professor Claire Wathes, who led the RVC
study team, the amount of milk offered correlated positively
with growth. "To achieve the recommended growth rate
of at least 0.7kg per day, calves need at least 750g of milk
powder per day. They should also be offered calf starter
ad lib, together with forage and clean water. This improves
animal health, as well as growth, and sets them up to calve
for the first time by the optimum two years of age," she said.
Dr Jessica Cooke, research scientist with Volac, pointed
out that the calf experiences significant health and
environmental stresses during the first two weeks of life and
that feeding more milk
from a few days of age
is important for lifetime
productivity.
"During the first few
weeks of life, calves are
unable to eat enough dry
feed to meet their energy
requirements and are
almost entirely dependent
on their milk feed," she
said.
"Early growth restriction can affect the long-term
performance of the adult cow. As expected, the heifer calves
offered more milk in the RVC study were found to have
better growth rates up to 63 days of age. But this research
also highlights the growth benefits long after weaning of
providing a good milk supply in early life. Those fed more
were heavier and taller at seven months of age.
As a result of this work and other studies, Volac has recently
refined its milk feeding recommendations. The result is a
`best- practice' feed plan to achieve optimum results.
"As a guide, calves should be fed five litres per day following
the colostrum period, increasing to a minimum of six litres
per day from day eight through to 35 days of age. Milk
replacer levels should then be gradually reduced over a
three-week period before weaning at day 56 (see table).
After three weeks, the rumen should have enough bacteria
fermenting enough solid feed to supply substantial amounts
of energy, ensuring no growth setbacks around weaning," Dr
Cooke said.
PRE-WEANED HEIFER CALVES
NEED MORE MILK
Week
Age
(days)
Twice daily feeding rates
(litres)*
am
pm
1
0-3
Colostrum
4 - 7
2.5
2.5
2
8 - 14
3
3
3
15 - 21
3
3
4
22 - 28
3
3
5
29-35
3
3
6
36-42
2.5
2.5
7
43 - 49
2.5
2.5
8
50 - 56
2.5
0
9
57
0
Recommended milk feeding plan, with a 3-week
weaning period, for calves fed twice daily
During the first few weeks of life, calves are unable to eat enough
dry feed to meet their energy requirements and are almost entirely
dependent on their milk feed to hit targets for optimal health and
lifetime productivity.
Dr Jessica Cooke, research scientist
with Volac
*Milk replacer mixed at either 12.5% or 15%.
Commercial Feature
Volac Advertorial 197x279.indd 1
26/03/2019 11:41