Buffer feeding is a tool used on many dairy farms in early spring, with it 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 as quickly as possible 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 adverse 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, soya hulls and soya bean meal are all high-quality ingredients that can be included, with the addition of straw acting as an excellent roughage source. Adding 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 formulated to accompany restricted grass and parlour feeding.
|Ingredients||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|
|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|
|Feed quality barley straw||1.0 kg/DM||0.9 kg/DM|
|Crude Protein Requirement||15-17%||15-17%|
|Crude Protein Supplied||17.7%||15.2%|
|Energy Requirement||0.88-0.95 UFL kg/DM||0.88-0.95 UFL kg/DM|
|Energy Supplied||1.01 UFL kg/DM||0.97 UFL kg/DM|
Energy values are based on predicted energy for a 600kg dairy cow in early lactation.