Tuesday, August 20, 2019

How to make most of grazed grass during the autumn

October 31, 2017 by  
Filed under Livestock

Dairy farmers taking advantage of the extended grazing window this autumn are reminded that grass dry matter variability could inhibit milk production without a well-balanced buffer ration.

Recent reports have shown that grass has huge variability in dry matter and acid detergent fibre levels, says Rob Fowkes, from Quality Liquid Feeds. Some areas have seen DM levels below 40kg/DM/ha, according to recent a AHDB report.

He therefore advises that it is essential that cows are supplemented with dense energy feeds to achieve their full potential. “Dry matter intake (DMI) has a significant impact on milk yield, body condition, fertility and disease prevention,” says Mr Fowkes.

A drop in body condition score of just 0.5 can result in a reduced milk yield of two litres/day and therefore rations need to drive dry matter intakes. “In lactating cows, we tend to find that energy, rather than protein or minerals, is the most limiting nutrient.”

Energy should be the first nutrient to check if cows are not milking as well as expected, milk protein is low or cows are losing excessive condition. “Measuring total dry matter intake for grazing herds rather than assuming intakes, is key to ensuring energy requirements are being met.”

A buffer feed containing a minimum 10.5 MJ/kg metabolisable energy should be fed alongside grazing for herds to utilise the last available grass. Incorporating a molasses-based liquid into a buffer ration can provide a good source of rumen fermentable energy to increase DMI.