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Samples of settled dust were collected in 14 animal houses and examined for the presence of bacterial endotoxin with the Limulus (LAL) test and the gas chromatography - tandem mass spectrometry (GC-MSMS) technique, based on the detection of 3- hydroxy fatty acids (3-OH-FAs) as chemical markers of the endotoxin lipopolysaccharide. The median concentrations of the endotoxin in dust determined with LAL test in sheep sheds, poultry houses, and horse stables were 15,687.5 µg/g, 8,081.8 µg/g, and 79.3 µg/g, respectively, while those determined with the GC-MSMS technique were 868.0 µg/g, 580.0 µg/g, and 496.0 µg/g, respectively. Statistical comparison of the results yielded with LAL test and GC-MSMS technique revealed a weak correlation between both methods. Fatty acids with 14-16 carbon chains (3-OH-C₁₄ and 3-OH-C₁₆) were predominant in the settled dust of the facilities under study. In conclusion, endotoxin in the concentrations detected in this study may present a respiratory hazard to both livestock animals and farm workers. Thus, the prevention measures aiming to lower the exposure to endotoxin in livestock facilities are highly desirable.
The mathematical model to analyze ammonia concentrations inside lifestock facilities has been made. The regression relationship of the intensity of the ammonia evaporation in the pigsty for the farrowing sows and their piglets has been determined. When the surface of the concrete floor of the stall is uneven and there is a manure layer of 0.5-1.0 cm thickness, the ammonia concentration in the pigsties of sows with piglets exceeds the upper permissible limit (20 ppm). When the relative humidity of the air is normal and the ammonia concentration exceeds the permissible limit, it should be reduced by technical and zoohygienic means ( by carefully cleaning the floor surface). This lowers the ammonia concentration from 25 ppm to 10-15 ppm, and its emission.
Air samples were collected on glass fi bre fi lters in 22 animal houses and 3 hay storage barns and examined for the presence of bacterial endotoxin with the Limulus (LAL) test and the gas chromatography – tandem mass spectrometry (GC-MSMS) technique, based on detection of 3-hydroxy fatty acids (3-OH-FAs) as chemical markers of the endotoxin lipopolysaccharide. The median concentrations of airborne endotoxin determined with LAL test in poultry houses, sheep sheds, piggeries, cow barns, and horse stables were respectively 62.49 μg/m3, 26.2 μg/m3, 3.8 μg/m3, 1.65 μg/m3, and 1.14 μg/m3, while those determined with the GC-MSMS technique were respectively 1.06 μg/m3, 7.91 μg/m3, 0.2 μg/m3, 0.31 μg/m3, and 1.42 μg/m3. The median concentrations of airborne endotoxin determined with LAL test and GC-MSMS technique in hay storage barns were much smaller, 0.09 μg/m3 and 0.03 μg/m3, respectively. The concentrations of airborne endotoxin (LPS) detected with GC-MSMS method in the air of sheep sheds were signifi cantly greater than in all other examined facilities, while those detected in hay storage barns were signifi cantly smaller than in all other examined facilities (p<0.05). The concentrations of airborne endotoxin determined with LAL test and GC-MSMS analysis exceeded in most of animal houses examined (91% by each method) the threshold limit value for airborne endotoxin of 0.1 μg/m3 proposed by various authors. A signifi cant correlation (p<0.05) between the concentrations of endotoxin determined with the LAL and GC-MSMS techniques was found in the air samples collected in poultry houses and sheep sheds, but not in other examined facilities. 3-OH FAs with C14-C18 chains were predominant in the air of the facilities under study. A signifi cant correlation (p<0.05) was found between the concentrations of endotoxin determined with LAL test and the amounts of 3-OH FAs with C14-C16 chains. In conclusion, endotoxin in the concentrations detected in this study may present a respiratory hazard to both humans and livestock animals.
Agricultural work, particularly livestock farming, is considered to be a notable risk factor for occupational diseases. Endotoxin as a major component of organic dust causes adverse health effects of the airways among farmers. Endotoxin concentrations in airborne and settled dust were measured in modern, naturally ventilated animal houses for different species. Median values of airborne inhalable endotoxin ranged from 16.9 EU/m3 for dairy cattle, 557.9 EU/m3 for beef cattle, 668.7 EU/m3 for pigs, 463.2 EU/m3 for laying hens, to 1,902 EU/m3 for turkeys. The endotoxin levels in settled dust followed the same pattern as the airborne samples. The concentrations were lower than in previous studies, but the proposed Dutch endotoxin threshold (50 EU/m3) was exceeded in most cases. Thus, endotoxin levels in modern animal houses still give concern for health and further reduction of endotoxin exposure in animal houses is desirable.
This paper presents results of the verification of a heat exchanger composed of gravitation thermal pipes installed in a broiler chicken feeding facility. The objective of the study was to verify the possibility of the application of a power management system including a heat recovery system in a heavy-duty environment of a broiler chicken fattening facility and to specify effects of the system upon the specific consumption of energy for space heating and ventilation of the animal house. The calculation of the thermal balance of the animal house documents that the power management system that includes a heat recovery exchanger unit may reduce the thermal capacity of external sources of heat in the animal house by 26.5% even when subject to extreme conditions and at the atmospheric temperature of -12°C and the age of chickens being 1 day. The results of the metering and calculations of the efficiency have proven that the heat exchanger reaches the operational efficiency of 10–47% and thermal efficiency of 20–80% even during the most demanding operational first twenty days of the breeding cycle of broiler chickens. The specific consumption of energy for space heating and ventilation related to 1 kg of the live weight of chicken in the animal house facility A provided with a heat recovery exchanger unit at the average atmospheric temperature during the cycle being 4.3°C amounted to 278.5 Wh. In the animal house B as not provided with the heat recovery exchanger units hosting the same number of chickens and provided with the same process and thermal loss due heat transmission through peripheral structures being one half compared to the animal house A, the specific consumption of energy per 1 kg of the live weight of chicken was 420.5 Wh.
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