There are many benefits to feeding high forage rations to dairy cows. Benefits include:
With highly digestible forage, it is common for high production cows to consume 1.5% of bodyweight as NDF and even higher for low production cows.
With higher quality forage, more needs to be fed in order to maintain rumen health and not simply allow more grain to be consumed as part of total TMR intake.
High quality forages required
Generally, 24 hour NDF digestibility of total TMR needs to be more than 60%.
The individual forages both corn silage as BMR and grass silage were more than 55% NDFD24.
The single greatest factor in determining quality is the stage of plant maturity.
Grasses at vegetative stage with NDF less than 52%, legumes at bud NDF 40 - 45%.
Corn varieties selected for high fiber or high starch digestibility.
As for preservation, pack density more than 20kgs per cubic foot at a minimum, the tighter the better.
Forage harvested too mature, too dry or too wet are not suited for high forage rations.
Farm management considerations
Feeding high forage rations and maintaining high milk production at the same time is possible.
Forage quality needs to be consistent as it becomes a higher proportion of the diet.
Forage inventory needs to be increased 15 - 30% or more and requires segregated storage space based on quality/NDFD.
During summer, aerobic stability of the TMR needs to be monitored.