Improving slurry management pays

Making full use of slurry took on a whole new dimension when Phil Brooke from Nicholson Farm near Leominster took the decision to go organic. Biotal SlurriNprove is helping get the best from this valuable resource.

Phil runs a herd of 160 all year calving cows on a robotic milking system with three Merlin M2 robots. The herd averages 9500 litres and has been milked through robots since early 2016 but moved to an organic system in April 2017.

“We decided to go organic in search of a more stable milk price,” Phil explains. “It had an impact on performance with yields falling back, in part as we had to stop growing maize.”

“The cows graze from late April to October but have free access back to the robots. When grazing the visits per robot drop back from 3.2 to 2.8.”

In the winter they are housed in cubicles over slats and are TMR fed a diet based on grass silage and wholecrop although this year he has added 300 tonnes of organic potatoes to the diet to make up for a reduced wholecrop tonnage, a consequence of the difficult season.

Since moving to the organic system, Phil has had to revise his slurry management.

“Previously, most of the slurry would have gone onto the maize land but now we need to improve the usage of it as slurry is the key nutrient supply to our grassland.”

“We need to apply it little and often using an umbilical system with some fields around a mile away. We look to apply the first dressing as soon as the NVZ window opens and follow this up in late March, after first cut and then after every cut. We need it to spread easily and consistently.”

“All slurry is stored in a clay lined lagoon which is gravity fed from the cow accommodation. In 2016 there was a considerable build-up of solid material in the lagoon which despite agitation would not mix.”

“It cost us over £2000 to move the build-up and spread it so we decided we had to do something to avoid problems like this in the future.”

Following discussion with local agent Tom Lazenby and John Thomas from Biotal who applied for the organic certificate for the product, Phil started using Biotal SlurriNprove in October 2017 with the aim of improving the pumping characteristics in particular. SlurriNprove is a biological treatment containing a specific blend of enzymes and bacteria which can improve the handling characteristics and nutritive value of slurry.

The enzymes and bacteria help break down some of the fibre fraction in the slurry, and reduce sedimentation of solids so less of a crust forms and the material is easier to handle with less agitation needed. Reduced ammonia The bacteria in SlurriNprove also compete with the normal microflora present in manures and responsible for slurry’s pungent odour. They reduce the ammonia production which leads to a more nutrient rich fertiliser with a reduced odour too. The first dose was added when the lagoon had been emptied and was topped up in January and June.

Phil adds the inoculant at the end of the lagoon furthest from the building, giving the bacteria a chance to multiply away from parlour washings.

“Adding the SlurriNprove has made a big difference to our slurry handling. As we are tight for storage we need to be able to get slurry out quickly and timeliness is essential in an organic system.”

“We can now agitate the entire lagoon from a single point in just 20 minutes which is saving a lot of time and money. There is far less crusting, the slurry is far more consistent and holds in suspension better. We have been able to improve our timeliness of spreading and so exploit the full potential of slurry.”