Identification of risk factors for sub-optimal housing conditions in Australian piggeries: Part 2. Airborne pollutants

The concentrations of total airborne bacteria, respirable endotoxins, ammonia, and respirable and inhalable particles were monitored in 160 piggery buildings in Australia between autumn 1997 and autumn 1999. The overall mean airborne bacteria, respirable endotoxins, ammonia (NH3), and inhalable and respirable particle concentrations measured were 1.17 x 10(5) cfu m(-3), 33.1 EU m(-3), 3.7 ppm, 1.74 mg m(-3), and 0.26 mg m(-3), respectively. The characteristics of the buildings and management systems used were documented at the time of sampling. A multifactorial general linear model (GLM) statistical procedure was used to analyze the effects of housing and management factors on the concentrations of the airborne pollutants. Both airborne bacteria and respirable endotoxin concentrations were affected by building classification (type), and respirable endotoxin concentrations were positively correlated with increasing humidity. The concentrations of airborne bacteria increased as the level of pen hygiene (cleanliness) decreased. The NH3 concentrations were primarily affected by level of pen hygiene, building volume, pig flow management, and season. Building classification, pig flow management, season, building volume, ventilation rates, and temperature affected inhalable particle concentrations. Respirable particle concentrations were primarily affected by building classification, pen hygiene, pig flow management, season, ventilation rates, temperature, and humidity. These findings suggest that environmental improvement strategies (such as improved cleaning, ventilation, and temperature control) are likely to reduce airborne pollutant concentrations in pig buildings and in the environment, thus improving the health and welfare of both pigs and farm staff.     

Dust in pig buildings

It is well documented in the international scientific literature that airborne dust in pig houses can cause serious health problems for humans as well as for animals. Extensive research has been carried out in different countries during the last few decades to improve the scientific understanding of air quality issues related to intensive animal production. Research and review papers were presented at the international symposium on Dust Control in Animal Production Facilities, held in Denmark in 1999. Different techniques have been used in order to reduce dust burdens in pig confinement buildings, but up to date only the procedure of spraying oil or a mixture of oil and water has contributed to reducing the indoor dust concentrations significantly. This article summarizes the current level of understanding of dust issues in intensive animal production buildings, mainly on the basis of papers presented at the above-mentioned symposium.     

Identification of risk factors for sub-optimal housing conditions in Australian piggeries: Part 4. Emission factors and study recommendations

The internal concentrations and emission rates of ammonia (NH3), total bacteria, respirable endotoxins, and inhalable and respirable particles were monitored in 160 piggery buildings in four states of Australia (Queensland, Victoria, Western Australia, and South Australia) between autumn 1997 and autumn 1999. Emissions were calculated for individual buildings as a product of internal concentration and ventilation rate, which were estimated by a carbon dioxide balance method. Relative humidity and temperature were also measured. The overall mean emission rates of NH3, total bacteria, respirable endotoxins, inhalable particles, and respirable particles per 500 kg live weight from Australian piggery buildings were 1442.5 mg h(-1), 82.2 x 10(6) cfu h(-1), 20.1 x 10(3) EU h(-1), 1306.7 mg h(-1), and 254.7 mg h(-1), respectively. Internal concentrations of key airborne pollutants have been reported in companion articles. Building characteristics and management systems used in the piggeries were documented at the time of sampling and used in the subsequent statistical modeling of variations in pollutant emission rates. The emissions model used all statistically significant factors identified during prior modeling conducted for individual pollutant concentrations and ventilation airflow. The identification of highly significant factors affecting emission rates and internal concentrations should aid the development of strategies for the industry to reduce emission rates from individual buildings, thus improving the environmental performance of piggery operations. In the second part of the article, specific recommendations are made based on the overall study results.     

Vegetable oil sprinkling as a dust reduction method in swine confinement

The aim of this project was evaluate the effectiveness of an oil sprinkling system as a dust-reduction method for swine production facilities. This article presents the results of the second-year experiment of a multi-year study. The first-year experiment demonstrated that a 5% oil-water emulsion automatically applied at the rate of 3 and 5 g/pig/day achieved a 23% to 34% reduction in total dust. The modifications for the second year experiment included: (1) increasing oil application rate to 7 and 8 g/pig/day, (2) replacing sprinkler heads to achieve a smaller droplet size and a more direct spray pattern on pen-floor surfaces, and (3) more closely matching the treatment and control rooms by stage in the pig production cycle. Four swine finishing rooms were used for this study; two were treatment rooms (soybean oil at 7 g/pig/day, and canola oil 8 g/pig/day) and two were control rooms. The treatment rooms had a low-pressure oil-sprinkling system, which sprinkled 5% oil-to-water mixture 12 times per day, 12 s each time. Concentrations of several environmental contaminants were measured. The average total dust concentration in the control rooms was 1.39 mg/m3. The average total dust concentration in the treatment rooms was 0.65 mg/m3. The treatment reduced dust by an average of 52%, (p = 0.0001). There was no difference in the degree of dust control between soybean oil and canola oil. The respirable dust concentrations were very low in all rooms, and there were no significant differences between rooms in ammonia, carbon dioxide, temperature, or humidity.     

蛋鸡福利化养殖模式及技术装备研究进展

自1999年欧洲福利法提出全面禁止传统笼养以来,世界各国开展了很多蛋鸡福利化养殖系统的研究,以保障蛋鸡福利,取得了很多方面的改进。然而,在世界上的主要蛋品生产国家中,福利化养殖设施所占蛋鸡养殖模式的比例仍然较低。随着人们对动物福利的重视和行业的可持续发展要求的提高,开发新型养殖设施的呼声日益高涨。根据国内养殖业建筑现状以及现代高产品种抗病力差的特点,发展福利化养殖装备提高蛋鸡鸡体本身的健康和福利,减少因药物使用带来的负面影响,中国开发福利化蛋鸡养殖设施以提高鸡体健康和福利以抵抗疾病,减少用药;同时促进舍内环境良好,创造适应现代鸡群的生存条件显得至关重要。该文通过概述世界现存的几种替代传统笼养的福利化养殖模式及装备,比较它们各自的特点以及它们在蛋鸡福利、生产性能及蛋品质、社会经济环境对它们产生的不同影响等方面的差异。提出并分析了不同养殖系统存在的主要问题。通过总结国外蛋鸡福利化养殖设施的优缺点,为国内蛋鸡福利化系统的开发提供参考。在改善行为福利的同时,还需要结合传统笼养鸡体与粪便分离、动物健康状况好、投资较低的优点,改变现有的福利化养殖装备系统设计。另外,该文展望了福利化养殖设施的发展方向,并提出了发展福利化养殖设施的新思路。     

Temporal variation of indoor air quality in an enclosed swine confinement building

Human health hazards can exist in swine confinement buildings due to poor indoor air quality (IAQ). During this study, airborne dust and ammonia concentrations were monitored within a working farrowing facility as indicators of IAQ. The purposes of this study were to assess the temporal variability of the airborne dust and ammonia levels over both a daily and seasonal basis, and to determine the accuracy of real-time sensors relative to actively sampled data. An ammonia sensor, aerosol photometer, indoor relative humidity sensor, and datalogger containing an indoor temperature sensor were mounted on a board 180 cm above the floor in the center of a room in the facility. Sensor readings were taken once every 4 minutes during animal occupancy (3-week intervals). Measurements of total and respirable dust concentrations by standard method, aerosol size distribution, and ammonia concentrations were taken once per week, in addition to temperature and relative humidity measurements using a thermometer and sling psychrometer, respectively. Samples were taken between September 1999 and August 2000. Diurnal variations in airborne dust revealed an inverse relationship with changes in indoor temperature and, by association, changes in airflow rate. Ammonia levels changed despite relatively stable internal temperatures. This change may be related to both changes in flow rates and in volatility rates. As expected, contaminant concentrations increased during the cold weather months, but these differences were not significantly different from other seasons. However, total dust concentrations were very low (geometric mean = 0.8 mg/m3) throughout the year. Likewise, ammonia concentrations averaged only 3.6 ppm in the well-maintained study site.     

Airborne antibiotic concentrations in a swine feeding operation

During the past 50 years, it has become common practice in the U.S. to add antibiotics to livestock feed to reduce disease and promote growth. Use of antibiotics in this manner has become the source of increasing controversy because overuse of antibiotics is suspected of leading to resistance in bacteria that cause human diseases. The purpose of this study was to measure airborne antibiotic concentrations in a swine production facility that routinely included antibiotics in feed. Samples were collected in a hog facility that included rooms devoted to farrowing, nursery, and growing operations. Analytical methods were developed to measure concentrations of the antibiotics tylosin and lincomycin in air samples. Tylosin was mixed in the feed in some of the rooms in the facility. While lincomycin was not added during this study, it had been used in this facility in the past and therefore was included in the analytical testing. Inhalable (n = 34), respirable (n = 37), and high-volume (n = 16) dust samples were collected on PVC filters over a two-month period. Tylosin concentrations were above the limit of quantification (LOQ) in 93% of the samples, while lincomycin concentrations were above the LOQ in only 9% of the samples (LOQ = 0.04 ng/sample). The average tylosin concentrations were 3, 18, and 49 ng/m3 in the respirable, inhalable, and high-volume samples, respectively. No occupational or environmental worker exposure criteria currently exist for antibiotics in air. The results of this study may be used to estimate potential swine production worker exposures and to further study the association between these exposures and health effects.     

Dust deposition and particle size in Mali, West Africa

Dust deposition samples were collected during April and May (1990) at four sites on the inland delta region of Mali in West Africa. High dust deposition rates were measured and characterised by considerable variations between sites. A major dust plume passed over the area, following a dust storm near Gao, 500 km to the east, however the contribution of this plume to overall deposition was surprisingly small.Dust particle-size characteristics indicate mixing of dusts from three sources. Long-distance dust deposition producing fine deposits (mainly < 5 μm); dust from regional sources producing deposits mainly in the size range 20–40 μm; and local dust arising from human activities, particularly vehicle and livestock movements, producing relatively coarse material in the size range 50–70 μm, plus some fines. Local dusts appear to have made the greatest contribution to deposition, with a moderate (though less than expected) contribution from the plume and a minor contribution from long-distance dusts.These results have implications for dust deposition studies aimed at quantifying dust contributions to soils. Although these Mali dust deposition rates are high (2.5–28.6 t⁻¹ km⁻² day⁻¹), the significant proportion of locally derived dust means that new dust inputs to the soils of the Inland Delta region of Mali are small.     

SE—Structures and Environment: Measurement and Analysis of Dust Spatial Distribution in a Mechanically Ventilated Pig Building

Dust has been implicated as a major contributor to the increased incidence of respiratory disorders among pig workers. Unlike gaseous contaminants, dust is not uniformly distributed within pig buildings. Dust spatial distribution is an important variable in the understanding of dust transportation and the implementation of appropriate control strategies. There is a lack of data on dust spatial distribution in livestock confinement buildings because of a lack of adequate sampling techniques. In this project, a multi-point sampler was used to measure the dust spatial distribution in a mechanically ventilated pig building. Experimental results show that there was a high variation in the dust spatial distribution within the mechanically ventilated pig building. Ventilation rate and diurnal change of weather affect the dust spatial distribution. It was shown that dust source control such as oil sprinkling at regular frequencies was an effective measure to control the dust levels. Room air cleaning such as dedusters can be used to reduce dust concentration and change dust spatial distribution.     

浅谈纵向负压通风

舍内环境因素诸如温、湿、有害气体、风速等很大程度上受通风工艺的影响。横向通风改为纵向通风后,舍内气流速率提高近6倍,且气流分布均匀,舍内氨气浓度和微生物数量分别降低50％和68％,粉尘含量也由34.6mg/m~3下降为11.4mg/m~3,节省电力23.7％     

西安市汽车站地表灰尘中重金属的污染评价及其来源识别

[目的]研究西安市长途汽车站地表灰尘中重金属的主要成分、可能来源及其污染水平,为改善汽车站内及周边环境现状提供科学依据。[方法]利用X-Ray荧光光谱仪对西安市内20个具有代表性的汽车站地表灰尘中Cu,Mn,Ni,Pb,V和Zn的元素含量进行分析,采用地积累指数法及潜在生态风险指数法评价灰尘重金属的污染水平及环境风险,利用主成分分析。聚类分析等方法来研究城市汽车站地表灰尘中重金属的主要成分及其可能来源。[结果]Cu,Pb,Zn均在不同程度上超过陕西省土壤背景值,其含量的平均值分别为36.3,107.7,113.5mg/kg。地积累指数法评价表明,除Pb为中度污染以外,其余元素均为无污染;潜在生态风险指数法表明,西安汽车站地表灰尘中的重金属元素处于中等污染水平,具有中等潜在生态风险。[结论]Cu,Mn和Ni主要来自于自然源和交通源,Pb和Zn主要来自汽车尾气的排放及零部件的磨损,V则主要来自于自然源。     

Is Oil-Well Produced Water Effective in Abating Road Dust?

Energy development in the Bakken and Three Forks formations of the USA has led to an increase in fugitive dust from unpaved roads. A dust abatement alternative that has been considered in this region is oil-well produced waters. The objectives of this study were to compare dust loading at sites abated with produced water to non-abated control sites and to determine if the elemental constituents in released dust are different compared to control roads. Three previously untreated unpaved roads were selected, and passive dust collectors were placed at 10, 20, 40, and 60 m from the road on the downwind side of the dominant prevailing wind in each mile section. Eighty-four days post-application, two sections treated with produced waters failed to reduce dust when compared to the controls. Dust elemental changes were found on two of the three roads. Elements that were found to have differences included Mo, Mn, Fe, As, Au, and Hg. Overall results indicated that oil-well produced water is not effective at controlling road dust. Results of this study are important to road managers who are contemplating the usage of produced waters to reduce dusts from unpaved roads.     

鸡舍排出空气过滤清洗装置设计与试验

为降低鸡舍排风对场区环境和生物安全的影响,规模化鸡场开始普遍采用在鸡舍排风机外侧设置过滤网的方式拦截羽毛和过滤粉尘。羽毛和粉尘在过滤网积聚易导致鸡舍通风效率降低,因此需要定期进行人工清洗,既费工费时又危害清洗人员呼吸道健康。为实现鸡舍排出空气的自动化高效净化,该研究设计了一种由过滤机构、清洗机构、驱动机构和控制机构组成的鸡舍排出空气过滤清洗装置,并进行了试验验证和运行能耗及成本核算。根据鸡舍排风污染物特性和过滤清洗需求,确定了过滤网材质及孔径、冲洗杆喷头选型及布置方式,以及驱动小车电机选型和车轮直径等关键参数,编写了装置运行控制程序。该装置通过自走式小车沿导轨往返运动驱动连接在过滤网内外侧竖直布置的冲洗杆和收集槽同步运动,冲洗杆采用喷水反向冲洗的方式,将过滤网内侧积聚的羽毛和粉尘冲洗至收集槽中,再排放至鸡场废水收集系统,从而实现过滤网的定期自动清洗功能,保证过滤效果的同时减少人力投入。试验验证结果表明,该装置运行可靠、控制简单,能够过滤拦截收集鸡舍排出空气中的羽毛,对鸡舍排出空气中粉尘的去除率可达到55.0%;运行能耗及成本核算结果表明,装置耗水量为2.17 L/(次·m^2<...     

Research on the Components of Dust Fall in Hohhot in Comparison with Surface Soil Components in Different Lands of Inner Mongolia Plateau

The dust fall in a region is closely related to upwind sources. Dust fall from sandstorms has a strong influence on industry, agriculture, and daily life. Hohhot, the capital of Inner Mongolia Autonomous Region, is downwind of the Inner Mongolia Plateau and experiences frequent sandstorms during the spring monsoon season. This study investigated the relationship between dust fall in the Hohhot area and surface soils on the Inner Mongolia Plateau. Samples of dust fall from Hohhot and surface soils from the plateau were analyzed for major and trace elements. The SiO₂ content of dust fall from sandstorms differs from that of the plateau soils by only 2.77%, indicating that the main dust fall source for Hohhot is surface soils from the plateau. Dust samples from coal smoke, roads, and buildings were used for comparison. The As content in dust fall from sandstorms is greater than that found in the plateau soils and in dust from non-sandstorm days. This indicates that As is added to the sand during transport from the plateau by coal factories near Hohhot. The second most important dust source is traffic, as evidenced by Pb contents. Preventing erosion of sand upwind of Hohhot during the spring monsoon is key to improving and managing air quality in the Hohhot region. This can be accomplished through management of the farm grassland areas.     

Human health effects of dust exposure in animal confinement buildings

Work in swine and poultry units is associated with exposure to significant levels of organic dust and endotoxins with the highest concentrations found in poultry houses, whereas values found in dairy and in cattle farming are much lower. Corresponding to this is an excess of work-related respiratory symptoms in swine farmers. A dose-response relationship exists between symptoms and number of working hours. Longitudinal studies have demonstrated an accelerated decline of lung function in swine farmers large enough to cause clinically significant disease in some farmers. Because of the large number of people needed in swine farming and the long working hours, swine farming has emerged as the major respiratory problem in farming. Experimental studies indicate that exposure has to be lowered substantially to avoid acute effects and longitudinal studies demonstrate that loss of lung function occurs in non-smoking swine farmers without respiratory symptoms and that accelerated decline in lung function occurs below endotoxin concentrations in dust (100 ng/m3) proposed as a safe threshold.     

蛋鸡舍冬季CO2浓度控制标准与最小通风量确定

中国现行的蛋鸡舍内CO_2浓度控制的农业行业标准为1 500 mg/m~3,主要适用于传统的刮板式清粪鸡舍。目前新建、改建鸡舍都采用传送带清粪方式,鸡舍内的相对湿度和氨气等有害气体浓度均明显减少,其冬季最小通风量和舍内CO_2浓度参数标准均有待重新研究。该文通过总结分析国内外相关学者对不同清粪方式蛋鸡舍内NH_3、CO_2浓度的测试数据,提出传送带清粪蛋鸡舍内CO_2浓度取值建议,并根据CO_2浓度平衡原理,提出该类蛋鸡舍冬季最小通风量的取值建议。结果表明:传送带清粪蛋鸡舍内CO_2浓度参数控制标准建议可取5 000 mg/m~3;蛋鸡舍冬季连续通风最小通风量为0.40~0.50 m~3/(h·kg)。该研究为中国新建、改建传送带清粪模式蛋鸡舍CO_2浓度参数标准的取值以及调控蛋鸡舍冬季通风与保温矛盾等问题提供了参考依据。     

蛋鸡舍臭气组成及不同管理措施对臭气特性的影响

随着中国蛋鸡养殖规模化的快速发展,蛋鸡场排出的臭气已成为影响周边环境质量的重要因素,但有限的关于蛋鸡舍臭气特性的研究严重制约着臭气污染程度的量化和除臭措施的制定,因此该研究通过对2种不同类型蛋鸡舍（商品蛋鸡舍和种用蛋鸡舍）的臭气进行综合分析,以探究不同管理措施（无管理操作、喂料、喷雾消毒、清粪）对臭气组成及其对臭气贡献率的影响。结果表明,2种类型蛋鸡舍的臭气组成和浓度相似,蛋鸡舍内臭气成分的浓度从高到低为NH3、挥发性脂肪酸（Volatile Fatty Acids,VFA）、挥发性含硫化合物（Volatile Sulfur Compounds,VSC）、酚类、吲哚类和胺类,对臭味贡献率从大到小为吲哚类、酚类、VSC、VFA、胺类和NH3。无管理操作和喂料过程中臭气组成和浓度相似,饲料的味道对蛋鸡舍臭气浓度影响较小。喷雾消毒和清粪过程中NH3、吲哚类和臭气浓度均显著增加（P<0.05）。此外,粪污在清粪带滞留期间,NH3浓度增加了6倍,胺类、VSC、吲哚类、酚类和VFA的浓度相对稳定。除NH3以外的其他成分主要来自肠道微生物的降解,对臭气贡献率高达99.99%,是臭味的主要来源。     

北京地区平养育成鸡舍粉尘浓度分布的测试分析

鸡舍内粉尘浓度过高，会危害饲养员的健康和家禽的生产力，还会对周围环境造成污染。了解鸡舍内粉尘浓度空间分布情况，有助于进一步分析粉尘释放和传播规律，为开发更有效的除尘方法，提供一定的理论支持。该文首次应用恒流量多点粉尘测量仪在横断面处均匀布点，对北京某鸡场平养育成鸡舍的粉尘浓度进行了监测，就温湿度、风速、鸡群活动状况等影响粉尘浓度的相关因素进行了比较分析。结果表明：在日间，影响粉尘浓度的主要因素为动物活动。舍内风速对粉尘浓度的影响不显著(p<0.05)。     

Acaricidal activity of constituents identified in Foeniculum vulgare fruit oil against Dermatophagoides spp. (Acari: Pyroglyphidae)

Acaricidal activities of components derived from Foeniculum vulgare fruit oil against Dermatophagoides farinae and Dermatophagoides pteronyssinus were examined using direct contact application and compared with that of the commercial repellent benzyl benzoate. The major biologically active constituent of Foeniculum fruit oil was characterized as (+)-fenchone by spectroscopic analyses. On the basis of LD(50) values, the compound most toxic to D. farinae was p-anisaldehyde (11.3 mg/m(2)) followed by (+)-fenchone (38.9 mg/m(2)), (-)-fenchone (41.8 mg/m(2)), benzyl benzoate (89.2 mg/m(2)), thymol (90.3 mg/m(2)), and estragol (413.3 mg/m(2)). Against D. pteronyssinus, p-anisaldehyde (10.1 mg/m(2)) was much more effective than benzyl benzoate (67.5 mg/m(2)), thymol (68.5 mg/m(2)), and estragol (389.9 mg/m(2)). These results indicate that the acaricidal activity of F. vulgare fruit oil likely results from (+)-fenchone and p-anisaldehyde. (+)-Fenchone was 20.3 times more abundant in the oil than p-anisaldehyde. (+)-Fenchone and p-anisaldehyde merit further study as potential house dust mite control agents or as lead compounds.     

Identification of risk factors for sub-optimal housing conditions in Australian piggeries: Part 1. Study justification and design

We undertook a literature search related to pig production facilities with two major aims: first, to review all the likely benefits that might be gained from air quality improvements; and second, to review previous research that had identified statistically significant factors affecting airborne pollutants and environmental parameters, so that these factors could be considered in a multifactorial analysis aimed at explaining variations in air pollutant concentrations. Ammonia, carbon dioxide, viable bacteria, endotoxins, and inhalable and respirable particles were identified as major airborne pollutants in the review. We found that high concentrations of airborne pollutants in livestock buildings could increase occupational health and safety risks, compromise the health, welfare, and production efficiency of animals, and affect the environment. Therefore, improving air quality could reduce environmental damage and improve animal and worker health. To achieve a reduction in pollutant concentrations, a better understanding of the factors influencing airborne pollutant concentrations in piggery buildings is required. Most of the work done previously has used simple correlation matrices to identify relationships between key factors and pollutant concentrations, without taking into consideration multifactorial effects simultaneously in a model. However, our review of this prior knowledge was the first important step toward developing a more inclusive statistical model. This review identified a number of candidate risk factors, which we then took into consideration during the development of multifactorial statistical models. We used a general linear model (GLM) to model measured internal concentrations, emissions, and environmental parameters in order to predict and potentially control the building environment.