| Congresso Brasileiro de Microbiologia 2023 | Resumo: 1468-2 | ||||
Resumo:Animal manure, such as that derived from poultry farming, can contain a high abundance of antibiotic resistance genes (ARGs). Thermophilic composting can be an alternative for reducing ARGs, but the evaluation of the effect of composting in real conditions on an industrial scale is rarely investigated. Therefore, the objective of this work was to evaluate the relative abundance and diversity of ARGs in fresh poultry manure - poultry litter and laying hen manure - and their respective composts. For this, fresh and composted poultry litter from two sources and in a third source, fresh and composted laying hen manure were collected. The identification of ARGs in manure was carried out through metagenome sequencing, using the DeepArg software. The ARGs’ relative abundance and diversity measured by the Shannon Index were evaluated using t-tests followed by Bonferroni corrections. Thermophilic composting had no significant effects on the reduction of ARGs in poultry litter (Bonferroni Test; p>0.05). However, a significant reduction in the relative abundance of ARGs was observed in composted laying hen manure, with an average reduction of approximately 50% (Bonferroni Test; p < 0.05). On the other hand, it was observed that the diversity of ARGs in all manures evaluated was reduced after composting (Bonferroni test, p<0.05), with average values of the Shannon index of fresh manures varying between 4.15 and 4.37, and between composted manure varying between 3.43 and 3.96. Thus, thermophilic composting proved to be a promising alternative for the management of poultry residues, since there was a significant reduction in the diversity of ARGs in all of them. Notably, thermophilic composting of laying hen manure promoted both a reduction in the relative abundance and a reduction in the diversity of ARGs, which indicates that this management alternative is a good alternative for reducing ARGs in this residue. Palavras-chave: antibiotic resistance genes, sanitation, manure, composting Agência de fomento:CAPES; FAPESP | |||||