Airborne Microbial Contents in Two Types of Swine Confinement Buildings in Quebec

Abstract

Airborne microorganisms were isolated with a sampler in two types of swine confinement buildings (farrowing units and fattening units). Respirable (particles less than 5 microns) and total dust fractions were obtained. Samplings were repeated every 2 weeks for a total of 6 samplings per unit between January and April. The predominant microorganisms isolated were bacteria (up to 1.25 x 10(6) CFU/m3) with an important fraction in the respirable size range (up to 0.5 x 10(6) CFU/m3). Only small quantities of gram-negative bacteria, yeasts, and molds were found. Identification of the colonies isolated revealed a great diversity of microorganisms present in the air of the different buildings. Enterobacter agglomerans, Moraxella, Acinetobacter calcoaceticus, and Pseudomonas were the most frequently identified bacteria. Scopulariopsis, Aspergillus, Penicillium, and Candida were the most numerous fungi. Faenia rectivirgula, the causative agent of farmer's lung, was not a major contaminant. The results show some differences in airborne microbial contamination between farrowing and fattening units; the distinction, however, is not clear-cut and was observed only for the total bacteria. The level of airborne microbial contamination in swine units does not significantly vary as a function of the outside temperature. Some species of bacteria and fungi isolated in this study are known to induce extrinsic allergic alveolitis. Other fungi are known to be potentially pathogenic for man. The air of swine confinement buildings is highly contaminated with bacteria, yeasts, and molds at a level up to 1200 time higher than so-called "normal air."

Characteristics of Microbial Aerosols Released from Chicken and Swine Feces

“…6 However, Cladosporium was not identified in another swine study. 16 Acremonium was the most abundant (29.4%) fungi in the swine fecal sample in the study presented here. This finding is consistent with a previous finding that Acremonium was the second-most predominant (7.6%) airborne fungal species during the composting of pig manure.…”

“…Penicillium has also been identified from chicken and swine feces, accounting for less than 10% of all colonies. This fungus has been identified frequently in swine buildings, but not as a dominant species, 6,15,16 and it has been identified as a predominant airborne fungus in factories that manufacture feedstuff. 28 Although Penicillium may originate from feed, Penicillium, identified in the current fecal sample, may have also resulted from the poor sanitation of the humid and poorly ventilated pig house.…”

Farming practices and the respiratory health risks of swine confinement buildings

“…Also, the sizes of buildings and the density of pigs raised vary considerably. It is known that the number of microbial contaminants, dust and gas levels vary considerably from one swine building to another [15,20]. Before generalizing that all SCB constitute a health risk, it is only fair to verify whether different buildings are similarly hazardous and whether modern designs and production techniques have improved or eliminated the risk to exposed humans.…”

Cyclosporin A increases the pulmonary eosinophilia induced by inhaledAspergillusantigen in mice

“…One was an Aspergillus aniigen mixture consisting of two strains of A. fumigatus and one strain of .4..^(/ri/.v isolated from swine confinement buildings [14], The other was an A. fumlgaliis strain isolated from Ihis /),s7' (T.tf/7/H.v mixture. Both antigens induced a lung inflammatory response characterized by a pulmonary eosinophilia similar to that induced by an ATCC A. fumigatus strain (data nol shown).…”