MANUAL ON IMPROVED FEEDING OF DAIRY CATTLE BY ... - Gart

Obviously the maintenance requirement of an animal is related to its
bodyweight. It has been established that a cow with a bodyweight of
450 kg, which walks during grazing about 5 km per day, has a
maintenance requirement of 3400 gramTDN and 275 gram dcp per day.
In relation to milk the production requirement depends strongly on the
fat-percentage in the milk. It has been concluded that a cow producing
milk with 4 % fat has a
production requirement of 330 gm TDN and 51 gm dcp per kg milk.
In Table 3 is indicated that 1 kg dairy meal contains approx. 648 gm TDN
and 108 gm dcp. That is more or less twice the production requirement
for 1 kg milk.
As a rule of thumb we may thus conclude that a cow is able to produce:
2 kg milk out of 1 kg dairy meal or equivalent concentrate mixture.
8.2 Daily fodder rations
We can use the following presumptions as a first step towards the
calculation of daily rations for cows. It is assumed that the animal has an
unlimited access to the roughage and eats as much as it likes. In case
of a cut-and-carry system, this means that about 10% of the supplied
fodder remains in the feed-trough as a leftover. Calculations show the
following indications of the quantity of milk a cow of approx. 450 kg
bodyweight can produce from some common fodder rations, which are
supplied unlimited.
Maintenance Kg milk per day
Natural grass
Poor quality - -
Good quality
Improved pastures
√ 6
Poor quality √ 0
Average quality √ 3
Good quality
Green fodder
√ 11
Napier/Bana grass (overgrown) √ 0
Napier/Bana grass (good quality)
Mixture with legumes
√ 8
Improved grass / Lucern (75/25%) √ 9
Napier grass / Desmodium (75/25%)
Hay
√ 0
Natural grass √ 0
Rhodes grass √ 0
Lucerne
Silage
√ 8
Maize √ 4
Napier/Bana grass
Straw
√ 3
Maize stover √ 0
Cowpea straw √ 0
TABLE 4: Estimates of the maximum quantity of milk which a cow of 450 kg is able to produce on
different fodder rations.
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Manual on improved feeding of Dairy Cattle by Smallholder Farmers