Pig production has expanded dramatically in recent years. A high pressure to environment has accompanied this increase.
As major environmental impacts result from livestock excreta, special care has to be given to manure management. If there is plenty of manure management techniques available, they are often only known locally. Besides, the farmer or the decision maker most often insufficiently knows the economic, environmental and public health implications of these technical options.

To fill this gap, the LEAD Initiative is preparing a Decision Support Tool (DST) on manure management to facilitate the identification, evaluation and selection of manure management options for confined pig production in rapidly growing economies.

Objectives of the Decision Support Tool

This Decision Support Tool will be designed to facilitate the identification, evaluation and selection of manure management options for confined pig production.

For example, the selection of options would be significantly affected if the decision maker’s primary objective is to use the manure as feed or as power generation rather than land application. A decision maker’s objective to sell solid fertiliser would result in a manure management option different from one that would emphasise on the liquid manure system.

This Decision Support Tool is intended for pig producers, farmers associations, extension services and related administration at local and national levels.

Design of the Decision Support Tool

Step 1: Formulate alternative solutions

Manure management system alternatives are developed using the total system approach, which consists of the following five basic functions (1) production, (2) collection, (3) storage, (4) process and (5) utilisation as shown in the schematic diagram of manure management system functions
(Click on the diagram for detailled information).

Step 2: Inventory manure management options

The entry point for the Decision Support Tool is the collection of manure.
The user is given a choice of manure management options according to the differences in livestock house structures (concrete floor or partially-slatted floor or slatted floor) and the collection of manure (in house separation or not) and the impact that the collection has on the consistency of the manure (slurry, liquid fraction, solid fraction).

Different options will be available for the decision maker. For example, the solid fraction of the manure can be composted or treated with the larvae of the black soldier fly or used for earthworm production or stored in heaps (anaerobic storage). For liquid fraction of manure or slurry, the management options can be grouped as composting, anaerobic digestion, aerobic digestion, separation, storage for sufficient time with cover or with additives, wetlands...Then the manure can be for example recycled as feed or as fertilizer (Click on the diagram for detailled information).

Step 3: Evaluate the manure management options

Alternative manure management options selected by the user will be evaluated to determine if they meet requirement of the user and if they are socially, environmentally and economically acceptable. The Decision Support Tool will provide additional information and links for the different options.

To facilitate the evaluation of each technique, a standard sheet will be presented to the user. These include the step (collection or storage or utilisation), the name of the technique, the reference of the articles or book cited, the type of input (e.g. solid or liquid manure), the type of output (e.g. compost, aerobically digested slurry, aerated slurry...), the aims of the technique (e.g. produce energy, removal of the nutrient), the process (brief description), N removal (%), P removal (%), BOD removal (%), Pathogens abatement (%), Water removal (%), type of equipment or design, investment cost, running cost, ease of use, farm type for which the technique is suitable, climate for which the technique is suitable, space for which the technique is suitable, environmental issues, human health issues, animal health issues (Click on the diagram for detailled information).