What is the contribution of piglet waste in the first week after weaning to greenhouse gas emissions?

Abstract

This study aims to characterize the waste of weaned piglets and estimate the emissions of N2O in kg of CO2 eq/kg of weight gain in the first week of housing. Primary data were obtained in the first week after weaning of piglets to identify how much waste from this animal category may affect the environment. The life cycle assessment was applied to verify the amount of manure and the emission of nitrous oxide (N2O) considering the weight gain (WG) of piglets in the first post-weaning week. Eight waste collections were carried out in two lots representing an average of 8,099 animals with initial and final weight of 5.01 and 5.84 kg, respectively. The production of residues was 0.128 kg of dry matter (DM) for each kilogram of WG produced. This waste production has an emission capacity of approximately 4x10-4 kg N2O/kg WG in the first post-weaning week. Considering that N2O has a global warming potential almost 300 times higher in retaining heat than CO2, each 1 kg of piglet produced can emit about 0.129 kg of CO2 equivalent from the N2O produced. According to the number of piglets evaluated in this study, the total emission can reach 1.85 tons of CO2 equivalent in the first post-weaning week alone.