Failing to balance the nutrients in grazed grass this summer could see milk fat content drop 0.25 percentage points and milk price cut 0.4-0.6ppl, according to KW nutritionist Mark Scott.
“DEFRA figures show national herd butterfats dropping from just under 4.10% pre-turnout to 3.80-3.85% by July in each of the last two years,” he states. “That’s a potential loss of around £1,000/month for a 200 cow herd averaging 27‑28 litres/cow.”
Further losses can come from the high levels of rumen degradable protein (RDP) in summer grass. Excess protein not captured by rumen microbes is excreted as urea, losing not only valuable protein but also the energy required to excrete it, equivalent to as much as 1‑3 litres/cow.
“Focus on properly balancing nutrient supply in the rumen to maximise conversion of all feed – including grazed grass – into milk and optimise milk value,” Mr Scott explains.
“Feeding 1-2kg FW of hay or baled silage will help sustain butterfats, for example, as will partially replacing cereals with soya hulls or sugar beet feed. And liquid feeds like Rouxminate and Molale can supply extra energy to balance grass RDP, whilst also boosting palatability, lifting intakes and supplying sugars to help drive forage fermentation in the rumen.”
