Airborne fungi in dwellings for dairy cows and laying hens.

The air of animal dwellings can contain great amounts of bioaerosol composed of dust, bacteria, fungi, and endotoxins. The composition may depend on animal species, building construction, animal accommodation, and microclimate parameters, to name just a few factors. Pathogens contained may be a serious threat to animal and human health.The aim of our study was to analyse the fungi aerosol content in a stable housing dairy cows and in a coop for laying hens over the three autumn months of 2007. The air was sampled on Petri dishes with Sabouraud glucose agar. After laboratory treatment, we identified the most common fungi. Their count in the stable ranged from 3.98 x 103 CFU m-3 to 5.11 x 104 CFU m-3 and in the coop from 6.89 x 104 CFU m-3 to 1.13 x 105 CFU m-3. The difference between the two animal dwellings was statistically different at the level of p<0.05. In both dwellings, the most common were the fungi Aspergillus sp., Penicillium sp., and yeasts, followed by Cladosporium sp., Fusarium sp., Mucor sp., Scopulariopsis sp., Alternaria sp., and Rhizopus sp.Our results are entirely in line with values reported in literature and are at the lower end of the range. They call for further investigation that would eventually lead to setting air quality standards for animal dwellings and to developing reliable monitoring systems in order to ensure safe food and safe environment.

Effect of microclimate on bacterial count and airborne emission from dairy barns on the environment.

The main microclimate parameters, i.e. bacterial count and airborne emission to the immediate environment, were analyzed in a dairy barn. Air temperature, relative humidity and air flow velocity were measured on an attested Testo 400 device (Testo Inc., Germany). Air samples were collected by use of a Merck MAS-100 device (Merck KgaA, Darmstadt, Germany) onto a commercially available nutrient Columbia agar (Biolife, Milan, Italy) and incubated for 24 h in an incubator at 37 degrees C work temperature. Measurements were carried out once a week in the morning, at noon, and in the evening during October and November 2002. In the barn, measurements were performed in the animal housing area along the feedlot, and outside the barn at a distance of 5 m, 25 m and 50 m eastward and westward from the barn. The measured dairy barn temperature ranged from 11.2 degrees C to 13.1 degrees C, relative humidity from 71.3-78.6 %, and air flow velocity from 0.09-0.11 m/s. The mean value of total bacterial count in the barn air ranged from 2.82 x 10 (4) cfu/m(3) at noon to 7.76 x 10(4) cfu/m(3) in the evening. Bacterial count decreased at particular measuring sites outside the barn, with Wilcoxon matched pair test showing statistical significance (p < 0.05) at a distance of 5 m eastward and 5 m westward of the barn.