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DEEP LITTER PIG PRODUCTION SYSTEM AS A SUSTAINABLE ALTERNATIVE FOR SMALL FARMERS

Small backyard farmers produce pigs mainly on concrete floors, which generates wastewater rich in nitrogenous substances created by the continuous washing of the sheds. The objective of this study was to integrate a systematic review of the information on the deep litter pig production system (SPCCP) as an environmentally sustainable alternative for small farmers in Mexico. The SPCCP uses a layer of absorbent organic matter on which the animals are kept. This technology is considered economical to implement, as it requires less infrastructure. The height of the bedding that favours the transformation of organic matter is 50 to 60 cm. Agricultural by-products such as plant debris or stubble can be used for bedding. The productive parameters of pigs in deep litter (CP) are adequate, with lower labour costs, and the animals have more time to eat, drink and play, which improves animal welfare. The product obtained from the deep bed at the end of the productive cycle has desirable properties to regenerate degraded soils or to enrich soils and can be used in agricultural crops. The SPCCP is simple and efficient, the infrastructure and equipment required are more economical; this production system improves feed conversion and daily weight gain, and benefits animal health and comfort. Since this system does not require washing the sheds, it reduces labour, as well as water needs, and does not generate wastewater. Therefore, the SPCCP complies with technical, financial, environmental, and animal welfare characteristics; it is an alternative for small backyard producers.