National Dairy Conference Questions Answered: Slurry additives benefits

All this week Teagasc Specialists answer the unanswered questions from the Virtual Dairy Conference on the Dairy Daily. Today's question is about Slurry additives and whether they are beneficial at making slurry agitation easier and at increasing nutrient supply to grassland.

With the large increases observed recently in fertiliser prices, attention has focused on maximising the role of slurry in meeting the nutrient requirements of pasture and silage crops. Slurry additives are available which claim to be beneficial at making slurry agitation easier and at increasing nutrient supply to grassland. 

In terms of slurry use, has any work been done on the claims of the slurry additive people?

Research at Johnstown Castle and AFBI has found no differences between treated (treated with a number of different commercially available additives) and untreated slurry in terms of slurry organic N conversion to plant available (ammonium) N or reducing N loss from slurry over the winter. Similarly some initial trials results have shown no evidence of an additional dry matter response to pastures on which treated slurry has been applied, compared to untreated slurry. Anecdotally, slurry additives make agitation/mixing of treated slurry easier.

The slurry additives mentioned in the Teagasc ammonia and greenhouse gas MACC documents are chemical slurry additives which are currently not commercially available and are cost prohibitive at farm level at current prices.

See more on the Virtual Dairy Conference 2021 here.

The complete Dairy Conference Proceedings can be viewed here and the individual articles were published on Teagasc Daily throughout last week. See Teagasc Daily - Dairy for more.