A recent report by Michael Garvey, a dairy development adviser, with the College of Agriculture, Food and Rural Enterprise (CAFRE), outlined a basic winter milking diet and how cows within this system diet should transition during the lactation.
Michael stated that: “Cows fed through a diet feeder should be grouped for feeding into early and late lactation groups and the amount of blend fed per cow in the feeder should be set to suit the lowest yielding cows in each group.
”For a diet feeder mix, each kg of blend adds approximately 2L of milk to the production from the silage [maintenance (M)+ figure] giving a combined base production M+ for the ration.
With good silage, 8kg of concentrates in the diet feeder supports a base production of 27kg in the early lactation group.
”Cows yielding 28kg of milk or more require to be topped up with additional concentrate.”
Michael added: “Cows should be moved between the groups as their yield declines. Cows more than 150 days in milk should be moved to the late lactation group.
”At this stage they may receive a greater proportion of their concentrate in the parlour than previously. However, to maintain feed efficiency, it is important that cows in late lactation are not over fed.
The late lactation group does not always require blend in the diet feeder, if parlour feeding is available. A feed rate of 0.45kg of concentrate per kg of additional required milk is satisfactory.
”Good silage and up to 8kg daily of parlour feeding allows cows with yields of 27kg of milk to be managed satisfactorily without concentrate in the wagon.”
Michael concluded: “A review of your feeding can refocus your objectives. Monthly use of a margin over concentrate programme can help monitor herd performance and ensure milk from forage is being optimised within your herd.”