Buffer feeding is a tool used on
many dairy farms in early spring, with this being particularly evident on farms
where grass availability is limited. Cows of higher genetic merit have a high nutrient
requirement in the immediate period after calving, and in general this cannot
be bridged by spring grass and parlour feeding alone. Adverse weather conditions,
high stocking rates and varying grass digestibility are all important factors
that impact on the level of additional feeding required.
Transitioning cows to a predominantly
grass-based diet is the main aim after calving. However, grass availability and
digestibility, ground conditions and stocking rates will all dictate the level
of grass available for inclusion in this regard. Early spring grass, contains
both high protein and digestibility levels and has a feed value that is closely
correlated to cow dry matter intake (DMI). Teagasc reports indicate, that a
rise of 1% in grass digestibility will increase (DMI) by 0.3-0.4kg (DM) per cow
and milk yield by 0.25 litres. Significant falls in grass (DMD) are not common
in early spring, but correct management practices undertaken during this period
will condition swards for improved grazing in later rotations.
Where grass availability is
limited, a well-constructed buffer feed should be used to supplement the feed
deficit. As a rule of thumb, a cow will require 5.5-6.0 UFL for maintenance
with an additional 0.43 UFL per kg of milk produced – solids dependent. Due to
reduced (DMI) the energy deficit in cows is at its greatest in the immediate period
after calving. This however, is well improved by week 6, with intakes fully
restored 10-12 weeks post calving. Confining this negative energy balance (NEB)
to the first 6 weeks of lactation is therefore extremely important, thus,
preventing any negative effects on future milk yield potential and cow
fertility.
Buffer feeding to deliver energy,
protein and fibre within this time period should therefore be considered to
offset this imbalance. A good buffer feed can result in positive responses to
milk yield and composition while also aiding to improve cow body condition
score (BCS). Maize silage, sugar beet pulp, citrus pulp, soya bean meal and
straw are all high-quality ingredients that can be offered. Including molasses
to this list will also have many positive effects, stimulating milk protein
production, increasing rumen digestion rates, preventing total mixed ration
(TMR) sorting and improving palatability can all be attributed to its
inclusion. However, it is important to note, that buffer feeding is there to
supplement grass intake and not replace it.
Detailed below are sample buffer feeds and are formulated to accompany restricted grass and parlour feeding
Diet Specification
|
Diet A
|
Diet B
|
Spring grass 79% (DMD)
|
3.5 kg(DM)
|
4.0 kg(DM)
|
Dairy nut 14% crude protein
|
1.7 kg(DM)
|
–
|
Dairy nut 16% crude protein
|
–
|
1.7 kg(DM)
|
Buffer Feed for diet wagon
|
–
|
–
|
Soya Hulls
|
2.6 kg(DM)
|
1.8 kg(DM)
|
Sugar cane molasses
|
0.4 kg(DM)
|
0.6 kg(DM)
|
Maize distillers grains
|
1.6 kg(DM)
|
–
|
Maize silage 25% starch
|
–
|
1.5 kg(DM)
|
Rolled Barley
|
0.4 kg(DM)
|
0.9 kg(DM)
|
Barley straw
|
1.0 kg(DM)
|
0.9 kg(DM)
|
Energy requirements
|
0.88-0.95 UFL
|
0.88-0.95 UFL
|
Energy supplied
|
1.01 UFL
|
0.97 UFL
|
Protein requirements
|
15-17% CP
|
15-17% CP
|
Protein supplied
|
17.7 CP
|
15.2
|
Energy values are based on predicted energy requirement for a 600kg dairy cow in early lactation.