Produção animal e o meio ambiente: uma comparação entre potencial de emissão de metano dos dejetos e a quantidade de alimento produzido

Abstract

RESUMO:O objetivo do trabalho foi efetuar a comparação das principais espécies de interesse agropecuário, em relação à eficiência de conversão das dietas em produtos de origem animal (carne ou ovo), produção de resíduo e potencial de emissão de metano, a partir da fermentação dos resíduos. Para isso, foram selecionadas cinco espécies de animais durante a fase de produção: 1) suínos, do nascimento ao abate (peso vivo (PV) final de 90 kg) ; 2) bovinos, do desmame ao abate (PV: 520 kg); 3) caprinos, do desmame ao abate (PV: 30 kg); 4) aves, durante toda a fase de postura (14,7 kg de ovos); 5) frango de corte, do nascimento ao abate (PV: 3,1 kg). Para a estimativa dos parâmetros propostos, foram medidos os dados do desempenho e efetuou-se a biodigestão anaeróbia dos dejetos produzidos pelos animais. De maneira geral, os dejetos dos ruminantes apresentaram altas concentrações de fibra e baixos potenciais de produção de biogás; no entanto, o menor desempenho destes animais na conversão do alimento em produto e a maior produção de dejetos fizeram com que eles apresentassem maiores produções de metano por kg de alimento produzido. PALAVRAS-CHAVE:conversão alimentar, coeficiente de resíduo, resíduos. ANIMAL PRODUCTION AND ENVIRONMENT: A COMPARISON BETWEEN POTENTIAL OF METHANE EMISSION FROM WASTE AND QUANTITY OF PRODUCED FOODABSTRACT: The aim of this study was to compare the main species of husbandry interest, in relation to the efficiency of food conversion into animal origin products (meat and egg), residue production and potential of methane emission from residue fermentation. This way, five species of animal during production phase were selected: 1) pigs, from birth to slaughter (final live weight (LW) of 90 kg); 2) cattle, from weaning to slaughter (LW: 520 kg); 3) goat, from weaning to slaughter (LW: 30 kg); 4) poultry, during the complete phase of laying (14.7 kg of eggs); 5 ) broiler, from birth to slaughter (LW: 3.1 Kg). For estimating proposed parameters, data of performance were measured and anaerobic digestion of produced waste by animals was done. In a general way, ruminant waste showed height concentration of fiber and low potential of biogas production, although the lower performance of those animals in the conversion of food into the product and increased production of waste, made that those animals showed greater production of methane per kg of produced food.

Anaerobic co-digestion of hatchery waste and wastewater to produce energy and biofertilizer - Batch phase

“…The biogas/methane production potentials per kg of the added TS and VS are more reliable once the interference of the water content present in the biomass is eliminated (Orrico et al, 2007), and they reflect the amount and quality of the carbon that can be converted into energy (Orrico Júnior. et al, 2011).…”

Energy management: a synthesis of scientific publications on biodigestion for waste management

“…All productive activity has an impact on the environment and the great challenge is to adapt animal production to the population's demand and at the same time to maintain sustainability (Lucas Júnior and Amorim, 2005). This fact became a central point of current discussions in several production chains, as the studies on composting, vermicomposting and anaerobic biodigestion techniques demonstrate, as they relate to aspects of sanitation, energy and nutrient recycling (Orrico Júnior et al, 2011;Martins and Oliveira, 2011). The use of biodigestors in animal production systems is important, because in addition to promoting the treatment of waste, they generate energy that can keep the production system energetically balanced (Orrico Júnior et al, 2011;Martins and Oliveira, 2011).…”

Effect of different substrates on composting of poultry litter

“…The composting process is the most suitable method for waste recycling, which besides having the advantage of reducing mass, volume and pathogenic micro-organisms, also enables the obtainment of a final product with good fertilizing characteristics that should be consciously exploited for agricultural production (Orrico et al, 2007). Like any other biological process, composting needs some factors to ensure satisfactory results, including the most important ones: temperature, moisture, pH and chemical composition of the material; the latter is the most challenging to be controlled and thus leads to varied results during the process (Orrico Junior et al, 2010).…”

“…Like any other biological process, composting needs some factors to ensure satisfactory results, including the most important ones: temperature, moisture, pH and chemical composition of the material; the latter is the most challenging to be controlled and thus leads to varied results during the process (Orrico Junior et al, 2010). Huang et al (2008) and Perez et al (2002) showed that the composition of the fibrous fraction of plant materials (cellulose, hemicellulose and lignin) significantly influences the degradation rate of these compounds, mainly when the lignin comprises the major part of the substrate. Thus, it is clear that the poultry litter content may vary significantly according to the initial litter material and the lignin content present in it (Orrico Junior et al, 2011).…”

“…Huang et al (2008) and Perez et al (2002) showed that the composition of the fibrous fraction of plant materials (cellulose, hemicellulose and lignin) significantly influences the degradation rate of these compounds, mainly when the lignin comprises the major part of the substrate. Thus, it is clear that the poultry litter content may vary significantly according to the initial litter material and the lignin content present in it (Orrico Junior et al, 2011).…”