NIS Boosts Rumen Function and Butterfats on Scottish Dairy Farm
Incorporating Nutritionally Improved Straw (NIS) into cow diets has resulted in an uplift in milk butterfats and reduced milk price penalties at Hotts Farm in Dumfries and Galloway.
Last summer, milk butterfats plummeted to 3.33% resulting in significant penalties for Lockerbie dairy farmers Gavin and Victoria Hamilton.With base milk price also at an all time low, they were keen to tackle the problem head on.
Gavin says: "We were losing about £4,000-£5,000 a month from the milk cheque. Butterfats kept on slipping and stayed below 3.5% for a couple of months."
As a result, the farm's vet consultant Will Tulley from EBVC suggested introducing NIS into the diet.
NIS is made up of chopped and milled straw which has been treated with sodium hydroxide and pelleted. The resulting alkaline product acts as a rumen buffer, whilst providing compressed functional fibre in a pelleted form.
With the Hamilton's herd yielding 11,800 litres a cow a year and being fed a proportion of wet first and second cut grass silage of around 22% dry matter, NIS would help improve rumen health and constituents.
Will explains: "In this herd, cows are being fed high levels of concentrate, together with wet silage, so there is little structural fibre. NIS provides structural fibre and also buffers the rumen, which helps boost rumen function and drive butterfats."
This is a good example of how NIS can help increase butterfats in herds where rumen function is challenged. Independent trial work carried out on other dairy units by EBVC has also found that, when rumen function is good, displacing straw with NIS can increase yields by 1.63 to 6.34 litres a cow a day.
At Hotts Farm, cows receive a full TMR, with the forage component made up of 90% grass silage and 10% wholecrop. Cows were traditionally fed 2kg a head of straw which was processed in the wagon. However the decision was made to incorporate 3.2kg of NIS per head into the diet and just feed 0.5kg of straw. NIS levels were gradually increased, while the amount of soya hulls and straw was reduced.
Gavin adds: "In an ideal world we wouldn't need to feed any straw, but because last year was such a wet year and we have two very wet grass silages, we are still feeding straw to help keep the ration open."
Having experienced some sorting when feeding higher levels of straw, Gavin says NIS blends well into the diet and he has witnessed an increase in dry matter intakes. Milk butterfats are currently 3.75%.
In recent months, Gavin has chosen to bring back diets slightly to reduce yields to avoid producing lower value "B" litres. As a result, it's difficult to assess the effect of NIS on yields. However he believes it hasn't had a negative impact.
"We've definitely got less problems with the cows. Fertility is fantastic at the moment. That's due a lot to the diet being toned back, but NIS must help with rumen health and cows looking well. I'm absolutely delighted with what NIS has done. It's cost effective as I'm getting improvements in butterfats and it’s saving me about £4,000 a month," says Gavin.
Read more about EBVC's NIS trial work.