An aerobiological study in the rural areas of Aragon (Spain) with a high population of pigs

Abstract

The development of intensive livestock farming in the swine industry has created problems associated not only with disease control but also with the disposal of excreta and other waste products. Both waste products and animals can contaminate the air of confinement swine buildings and their surroundings. The objective of this work was to determine the concentration and species composition of the bacterial and fungal microflora in the air of different villages with a high population of pigs in their surroundings. Outdoor air sampling was conducted in 24 rural urban nucleus of Aragon (Spain). In each site, three sampling points were done: one in the center of the town, another in the outskirts of the same town, and the last one in the surrounding farms. Microorganisms were isolated with a sampler Surface Air System (S.A.S.). In the quantitative analysis, the potential risk of exposure to airborne microorganisms decreased outside and near of the farms and, of course, in other sampling points, because the airborne levels of total bacteria and fungi found in the three points are similar, slightly higher in the surrounding farms and lower inside of the buildings. The genera Staphylococcus and Bacillus among isolated Gram-positive bacteria were the most common, while among the Gram-negative genera often were Alcaligenes and Acinetobacter in most cases observed. In fungi, the most isolated genera were Cladosporium, Aspergillus, Penicillium and Alternaria, which are very important aeroallergens. In this work, were found no differences between the three sampling, which are indicative of few microbial contamination of the air from swine confinement buildings at short distances.