Manure Management by Animal

Manure is not one material. Pig slurry at 92% moisture is a pumpable liquid that must be separated before it can be stacked. Goat droppings at 45% moisture are already a stackable solid that composts in a fortnight with almost no preparation. Layer manure is dry enough to pile but so rich in ammonia that it will burn a crop and offend a neighbour within a day. Horse manure arrives mixed with bedding, which supplies exactly the carbon the manure lacks. Cattle slurry has more water than all of them combined and more fibre than any of them except horse.

Those differences decide the equipment list more than the tonnage does. A 10 t/day goat manure project needs a shredder, a small turner, a screener and a bagging scale. A 10 t/day pig slurry project needs a separator, a flocculation or settling system, a much larger fermentation area, a deodorising strategy and a plan for the liquid fraction — and the equipment budget can easily be twice as large for the same tonnage of finished fertilizer.

This section collects our practical guidance by animal. Each page covers how much manure the animal produces, what its handling characteristics are, the process route that works, the machine set and the specific mistakes we see most often. If you already know your animal and your daily volume, that is enough for us to give you a meaningful process recommendation.

Manure management is increasingly a compliance subject as well as an agronomic one. In most jurisdictions a farm must be able to demonstrate that manure storage has enough capacity for the longest period during which spreading is prohibited, that fields receive no more nitrogen than the crop can take up, and that no runoff reaches surface water or groundwater. Nutrient accounting, storage capacity and spreading records are the three documents usually requested.

Processing manure into compost or fertilizer changes this picture substantially, and generally for the better. Composting reduces the volume and stabilises the nitrogen, so storage requirements fall. A registered fertilizer product can be sold and transported rather than applied to land within a fixed area, which removes the land-bank constraint that limits many large livestock operations. And the thermophilic temperature reached during composting provides documented pathogen reduction, which is increasingly required for any product moving off the farm.

In practice, the farms that find compliance easiest are the ones that installed treatment equipment before they were required to. Separation, a concrete composting pad with proper drainage and a covered storage area are the three investments that do the most to reduce both environmental risk and regulatory exposure.