Winter milking: Finding the 'sweet spot' with concentrates
With winter milking being a costly system, ensuring you formulate the appropriate diet is essential in boosting margins.
Concentrates play a significant role in the majority of these winter-milk diets, but it is important to play the balancing game, as excessive or over-feeding is wasteful and expensive.
This 'sweet spot' is crucial as there is not going to be any more benefit in production if you are overfeeding, but it will happily continue to burn a hole in your wallet.
Ideally, you should be formulating the diet to suit the lower yielding cows in the herd and making further adjustment based on the quality of silage being fed, then if possible feed the higher yielding cows a higher feeding rate.
Winter-milk
Concentrates act as substitute, so the more you feed the more their forage intake will reduce, which will ultimately reduce the response rate of the concentrates.
This ends up being an expensive system, as you are effectively swapping out a relatively cheap forage for an expensive concentrate.
Feeding less concentrates starts with having good quality silage to feed your milking cows, as less energy will be required to bridge the gap in the diet.
You should test your silage as soon as possible so you know what the value of your silage is and how much silage your cows are going to need to meet their nutritional demand.
This will help you formulate a plan for winter and save on unnecessary spending on concentrates.
The concentrate feeding levels at different levels of silage quality and different yields, as per Teagasc, are as follows:
| Milk yield | 65 DMD | 70 DMD | 75 DMD |
|---|---|---|---|
| 20L | 5.5kg | 4.0kg | 3.0kg |
| 25L | 8.0kg | 6.5kg | 5.5kg |
| 30L | 10.0kg | 8.5kg | 7.5kg |
| 35L | 12.5kg | 11.0kg | 10.0kg |
High dry matter digestibility (DMD) silage leads to increased forage intake, which in turn drive milk solid production and boosts better rumen.
The typical 600kg cow will require 7.5kg of concentrate to produce 30kg of milk on 75% DMD silage, whereas that requirement would be 10kg if the silage was 65% DMD.
Typically, every five unit drop in DMD will need 1.0-1.5kg extra concentrates to compensate for the lower energy level.
A cow producing high litres will require more energy than those producing low litres, so every diet needs to be adjusted. This can be done through the grouping of animals.
Poor silage quality will lead to reduced intake levels, it may also alter neutral detergent fibre (NDF) levels in the diet, meaning extra fibreous feeds such as straw will be needed.
