Plan rations ahead, but be prepared to react
As we bed down for autumn, cows will increasingly be turning to winter rations, and where used, maize silage will be well integrated into the diet.
Managing this transition is key to a successful winter feeding program, but we must be prepared to react quickly to ensure our herd's performance is maximising the milk contract requirements.
In August 2017 the average milk price for Great Britain stood at 6.5 per cent higher than July and 36 per cent higher than the same time last year, but some milk contracts have a large variation depending on milk constituents. While the last two years' low milk price means farmers should still be keeping costs down, there is an opportunity to increase milk price by feeding for milk solids which could impact farm profitability.
While we should always look at our own situation, typically 2017 first cut and second cut grass silage averages have been better quality than 2016. Similarly, July and August milk production has increased on last year by 1.2 per cent and 1.8 per cent respectively.
Comparing this trend to milk constituents, both milk fats and proteins have slightly increased through the same period, indicating improved energy and fibre digestibility. With some milk contracts a 0.1 per cent rise in protein and fat percentage can increase milk price by 0.45ppl and 0.32ppl respectively - that’s £7,700 extra income per 1 million litres sold.
There are many factors involved including breed and selection, but diet and balance play a critical role in manipulating milk constituents.
Energy status and milk proteins go hand in hand, milk protein percentage is a key indicator for early negative energy balance and therefore fertility, feeding highly digestible feeds and forages will have a positive impact on milk proteins. More specifically feeding starch and sugars will drive a proportionate response from the rumen. This impacts on amino acid synthesis and therefore milk protein. This is why we can see a positive response to both milk yield and milk proteins when maize and cereal silage is included in the diet.
To drive milk constituents on farm, identify what the limiting factors are and therefore what element is going to provide the greatest return.
For example - if milk proteins are low and forage quality is below average and mature, drive glucogenic energy through increasing fermentable carbohydrates such as maize, cereals and/or molasses products. If milk fats are limiting and forages are high quality with limited structure, add digestible fibre such as sugar beet, pulp or soya hulls and possibly structural fibre to slow down the rumen throughput and allow the rumen microbes more time on attachment to the feed to break it down.
Buffers and probiotics may also be required to raise rumen pH to the optimum of 6.2pH, creating a more favourable environment for fibre digesting bacteria.
Adam Clay is NWF technical manager.
