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REPLACEMENT HEIFER CARE
X
First things first; weigh your weanling (called R1's) and
your incalf (R2's) heifers now to see how they compare
with the targets.
Targets: R1's and R2's should be 40 per cent and
80 per cent respectively of their mature weights.
Mature weights are: HF = 580 kg: NZ/Br Fr =
550kg; J x HF = 545kg.
Then act on the results.
X
On many farms, replacement heifers are below target
weights at most stages in their lifetime, with the result
that culling from 1st to 2nd lactations are very high.
Being away over targets is also seriously damaging:
Weanlings gaining more than 0.8kg/day deposit
too much udder fat and consequently milk
poorly,
Heifers calving down 40+ kgs over target
weights, while milking more in their 1st lactation,
subsequently milk a lot less and suffer early
culling.
X
The target weights for 1st November are as follows:
Breed
Weanling (40 % Mature Wt)
In Calf Heifers (80 % Mature Wt.)
Holstein:
224 kg
448kg
British Fr/NZ Fr
220 kg
440 kg
Jersey x HF
218 kg
436 kg
X
Animals under target should get extra meal. With good
silage, for every 10kgs R1's are under target they need
40kgs of extra meal and for every 10 kgs R2's are under
target they need an extra 60 kgs meal over a period to
bring them to target.
X
Heifers suffer on most farms at this time of year.
They are left to "run around" cleaning up bad
pastures, either at home or particularly on out -
farm blocks.
There is only 90-120 days to calving.
At an expected weight gain of 0.75 Kgs per day,
you need 100 days to put on 75Kgs.
Remember the last 3-4 weeks before calving do
not count for weight gain as the animal's intake
is way below normal and she diverts most feed
into calf growth.
Mix the incalf heifers with the 1st calvers so as
to minimise stress now and particularly after
calving when stress then can have a detrimental
effect on her subsequent weight gain.
X
Use Tables 2 & 3 to plan your meal feeding strategy for
your weanlings.
Meals will give the following weight gains:
1kg and 2 Kgs of meal will give 0.25 and 0.4 Kgs
gain per day respectively.
Weanlings should be fed to gain at least 0.5Kgs
per head per day. Some will have to gain more
to catch up.
X
At grass next spring they should gain 0.75Kgs.(60 days
of Mar and Apr X 0.75=45 kgs). From this information
you can decide what management treatment animals
of various weights require.
Table 2: Meal requirements for Weanling Heifers on Silage.
Weanling
Silage DMD
65
70
75
Gain on Silage only (kg/day)
0.24
0.41
0.58
Light Weanlings
(Meal to give 0.7kg/day)
2.0
1.4
0.5
Heavy Weanlings
(Meal required to give 0.5kg/day)
1.0
0.4
-*
*Because of the good response to meals at low levels, feed at least 1kg/
day to all weanlings until January.
X
It is obvious from above that:
Silage must be analysed (contract rearers must do also)
A weighing scales is essential to manage heifer target
weights, therefore, discussion groups should buy one
together.
X
With good management weanlings that are 20 per cent
under target would achieve target mating weights.
X
All this information is essential to bring to the
attention of contract calf rearer's so that subsequent
hastle doesn't arise.
We have had cases where the owner of the animals has
been very thrusting of the rearer's ability, based on past
history, and hasn't monitored silage quality and animal
target weights. There is only one looser in that situation!
NOVEMBER 2019
Management Hints
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NOVEMBER 2019
www.irishfarmersmonthly.com
Management Hints
51