2 minute read
Maximising Milk or Meat From Forage With Molasses
Drive forage intakes
Increasing feed costs combined with good silage stocks are leading some producers to question which inputs can be reduced or removed from rations this year, with many putting a greater reliance on forage, sometimes with a hidden detriment to the diet if not balanced. This leads the question, what should be considered when assessing the use of molasses in ruminant diets?
Sugars are often ‘lumped together’ with starches in ration formulations and decisions made dependant on the cost of individual raw materials. There is increasing evidence to show that starches and sugars perform very different roles in the rumen, and should be assessed in isolation.
It is well known that sugars drive forage intakes, but it’s not just because of the sweet taste and smell! Research has shown that when supplementing diets with 6-8% (or above!) of a cow’s dry matter intake as sugar, we stimulate not only the bacteria, but in particular the protozoa in the rumen, which are very efficient at digesting fibre. We talk a lot about bacteria in the rumen, and although they play a vital role in the fermentation of feeds, protozoa are perhaps overlooked in their value in terms of fibre digestion. Protozoa love sugar!
Re-creating grazed grass
By feeding the protozoa to improve digestibility, we are maximising the potential of the forage. Think of a cow at grass. Her muck may be loose, due the high moisture content at grazing, but there is very little discernible fibre in her muck – her rumen microbes are working efficiently to maximise the digestion of fibre. What’s the main difference between grazed grass and fermented silage? SUGAR! A grazing cow might consume up to 20% of her dry matter intake as sugar, whilst a housed diet without supplemental sugar will average around 2.5-3%. It is also worth considering total ration sugar level when we buffer feed in the shoulders of the grazing season, or even finishing beef cattle rations as they are typically made up of straw or maize silage, all very low sugar and high starch.
We know that when we feed high levels of starch, we run the risk of producing too much acid (propionate) and causing rumen acidosis and milk fat suppression. Research has shown that sugars fermenting in the rumen produce a greater supply of a less strong acid (butyrate) which will not lead to an acidosis challenge. A high sugar diet will therefore not cause the same acidosis risks, and can lead to an improvement in microbial protein levels, energy to the animal for growth, and milk fat percentage.
When farmers are wanting to maximise meat or milk from forage, sugars should be considered a vital tool to ensure the most nutrition is digested from the diet regardless of the quality of the silage.
Bethany Parry
Technical Product Development Manager
m: 07771 740857 e: bethany.parry@wynnstay.co.uk
Bronwen Philwret
QLF Sales Manager
m: 07341 853721 e: bronwen@qlf.co.uk
