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 3.98×103 CFU m-3 to 5.11×104 CFU m-3 and in the coop from 6.89 ×104 CFU m-3 to 1.13×105 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.
Determination of Aspergillus Fumigatus Allergen 1 in Poultry Farms Using the Enzyme Immunoassay
Poultry farms contain high levels of allergenic fungi, and Aspergillus spp. is the most common genus of moulds. Aspergillus fumigatus antigens are responsible for the development of several respiratory diseases including asthma. The aim of this study was to measure the mass fraction of Asp f 1, a major allergen of Asperillus fumigatus in 37 indoor dust samples collected from four poultry farms in a rural area of the Zagreb County (Croatia) using the enzyme-linked immunosorbent assay. More than 62 % of dust samples had detectable Asp f 1 levels (limit of detection 3.6 ng g-1). The overall mean Asp f 1 level was 17.9 ng g-1 [range (3.8 to 72.4) ng g-1]. Satisfactory results were obtained for analytical within-run imprecision (6.7 %), between-run imprecision (10.5 %), and accuracy (91 % to 115 %). Microclimate parameters (air temperature, relative humidity, and velocity) were within the recommended ranges in all poultry farms. This study has shown that Asp f 1 settles on dust at poultry farms and that occupational exposure to this allergen deserves monitoring in livestock buildings.
In the present study, postural behaviour was compared between gilts kept in service unit with different types of flooring during all seasons. The study included four 28-day production cycles and 10 gilts per cycle, equally divided into a control and an experimental group. Control gilts were housed in gestation stalls with slatted concrete floor, whereas in the experimental group the floor was covered with an adjusted rubber mat. Postural behaviour of gilts was observed 4 times per cycle for 4 hours. Study results showed that during cooler seasons, gilts in concrete stalls spent more time standing and lying sternally, whereas gilts in matted stalls were mostly lying, predominantly laterally (P<0.001 all). There were no significant between group differences according to the time the gilts spent sitting or the frequency of changing posture in any season observed. Nevertheless, experimental animals spent significantly less time changing standing to both lying positions during all seasons (P<0.01 all). In conclusion, rubber mats may improve lying comfort in gilts; however, when using rubber mats, the house thermal conditions should be taken in consideration.