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1.
High levels of dust and microorganisms are known to be associated with animal confinement rearing facilities. Many of the microorganisms are carried by dust particles, thus providing an excellent vector for horizontal disease transmission between birds. Two environmentally controlled rooms containing female broiler breeder pullets (n = 300) were used to evaluate the effectiveness of an electrostatic space charge system (ESCS) in reducing airborne dust and gram-negative bacteria levels over an 8-wk period (starting when the birds were 10 wk old). The ESCS was used to evaluate the effectiveness of reducing airborne microorganism levels by charging airborne dust particles and causing the particles to be attracted to grounded surfaces (i.e., walls, floor, equipment). The use of the ESCS resulted in a 64% mean reduction in gram-negative bacteria. Airborne dust levels were reduced an average of 37% over a 1-wk period in the experimental room compared with the control room on the basis of samples taken every 10 min. The reductions of airborne dust and bacteria in this study are comparable with earlier results obtained with the ESCS in commercial hatching cabinets and experimental caged layer rooms, suggesting the system could also be applied to other types of enclosed animal housing.  相似文献   

2.
Commercial hatcheries typically infuse hydrogen peroxide or formaldehyde gas into hatching cabinets to reduce airborne pathogens that may lead to disease transmission during the hatch. A nonchemical option, an electrostatic space charge system (ESCS), was customized for full-sized commercial hatching cabinets and was tested extensively in broiler hatcheries. The ESCS cleans air by transferring a strong negative electrostatic charge to dust and microorganisms that are aerosolized during the hatch and collecting the charged particles on grounded plates or surfaces. In studies with three poultry companies, the ESCS resulted in significant (P < 0.0001) reductions of airborne dust of 77%-79%, in Enterobacteriaceae and fungus levels not significantly different (P > or = 0.05) from those with formaldehyde, and in 93%-96% lower Enterobacteriaceae than with no treatment or with hydrogen peroxide treatment (P < 0.01). The ESCS significantly (P < 0.05) reduced airborne Salmonella by 33%-83% compared with no treatment or hydrogen peroxide treatment. Results of this study suggest that the ESCS is a viable alternative to chemical treatment for reducing airborne pathogens in full-sized commercial hatchers, and it also provides dust control and containment, which should be helpful in reducing cross contamination and loading of ventilation ducts within different areas of the hatchery.  相似文献   

3.
Reduction of airborne dust in enclosed animal housing has been shown to result in corresponding reductions in airborne bacteria, ammonia, and odor. The search for strategies to reduce particulate matter and ammonia emissions from animal housing has led to considerable interest in the poultry industry for practical systems to reduce these air emissions. Technologies that have been shown to be effective for reducing airborne dust in animal areas include misting with an oil spray, water mists, extra ventilation, and electrostatic space charge systems. An electrostatic space charge system (ESCS) was designed to reduce airborne dust and ammonia emissions from a commercial broiler production house. The ESCS for this application was based on patented technology developed to reduce airborne dust and pathogens. Two commercial broiler houses with built-up litter (a control house and one outfitted with an ESCS unit) were monitored for dust and ammonia concentrations over a period of 7 flocks. Results of this study indicate the ESCS significantly reduced airborne dust by an average of 43% and reduced ammonia by an average of 13%. Power consumption of the ESCS system was less than 100 W when in operation. Commercial application of this technology within the production house has the potential to improve in-house air quality and reduce particulate emissions.  相似文献   

4.
The use of chemicals in food plant sanitation for removing and killing microorganisms could be reduced by the use of alternative nonchemical interventions. Supercharged negative air ionizers have shown potential to effectively reduce airborne and surface microorganisms. In our earlier studies, a small chamber, controlled at 85% relative humidity and supercharged with a −25 kV electrostatic space charge system (ESCS), was used to transfer a strong negative charge to bacteria on stainless steel surfaces. The ESCS treatment caused the levels of biofilm bacteria from chicken carcass rinses to be significantly decreased with 99.8% efficiency at a distance of 18 cm with ion densities of 106 negative ions/cm3 or more. In the present study, effects of the −25 kV charge of ESCS on specific pathogens important for food safety were studied. Treatment of Campylobacter jejuni, Escherichia coli, Salmonella enteritidis, Listeria monocytogenes, and Staphylococcus aureus achieved up to a 4 log reduction with 99.9% reduction efficiency in 3 h. Treatment of bacterial spores of Bacillus stearothermophilus achieved up to a 3 log reduction with a 99.8% reduction efficiency in 3 h. These significant reductions for 5 species of pathogenic bacteria and bacterial spores suggest that the ESCS is a promising alternative treatment for reduction of microbial load in a food-processing facility with the potential to reduce the amount of antimicrobials used.  相似文献   

5.
The species composition of airborne gram-negative bacteria and the relationship between inhalable endotoxin, inhalable dust and airborne bacteria were studied in 4 pig houses. The airborne gram-negative bacterial flora was dominated by Enterobacteriaceae. Within the Enterobacteriaceae the species E. coli and Enterobacter agglomerans were predominant. Significant correlation were found between the concentration of inhalable dust and inhalable endotoxin as well as between the concentration of airborne gram-negative bacteria and inhalable endotoxin. However these correlation were not very strong. With respect to the characterization of the potential hazard of organic dust exposure, measurements of the concentration of airborne dust or airborne bacteria should not be used for the estimation of the concentration of airborne endotoxin.  相似文献   

6.
Consumption of poultry meat is associated with human Campylobacter and Salmonella infections. One way to control the presence of these bacteria in broiler flocks is to make chickens less susceptible for colonisation. Acidification of feed may be a tool to reduce the Campylobacter and Salmonella carriage in broiler chickens. In the present experiments an acidified feed with high levels of organic acid, 5.7% lactic acid and 0.7% acetic acid, was applied. In an in vitro experiment the reduction or growth of Campylobacter and Salmonella was measured after addition of 10(7)cfu of these bacteria into a conventional broiler feed, acidified feed and fermented feed, whereas the numbers of Salmonella increased in non-acidified feed. The number of Campylobacter decreased 2-3 (10)log cfu. In the acidified and fermented feed a complete reduction of Campylobacter was observed within 20 min, and a total Salmonella reduction started after 1h, and was complete after 2h. Subsequently, an in vivo experiment with 100 individually housed broiler chickens showed that chickens fed acidified feed were less susceptible to an infection with Campylobacter than were chickens fed conventional feed. The size of reduction was however limited. The susceptibility for Salmonella colonisation was not affected by acidified feed. It is concluded that the role for acidified feed in the control of Campylobacter and Salmonella is limited.  相似文献   

7.
Prevention of Salmonella contamination of poultry products requires detailed knowledge of the main sources associated with its presence in the production system. The aims of this study were to determine the main sources of Salmonella contamination in broiler production during growing, to assess the risk factors for Salmonella contamination at the end of the rearing period and to determine the main serovars involved in broiler production systems in Eastern Spain. A total of 65 different broiler houses from different farms were sampled. Each house was sampled at different times during the rearing period. First, when the previous flock was taken to the slaughterhouse, samples of dust, surfaces and previous flock faeces were collected. After cleaning and disinfection (C&D), samples of dust and surfaces were also taken. On the first day of rearing, samples of water, bedding, farming boots, meconiums, delivery-box liners and feed were collected. During rearing, feed samples were taken directly from the truck and from feeders. On slaughter day, samples of dust, surfaces, water, feed and faeces were also collected. Finally, two days after slaughter, carriers (rodents, flies and beetles) were trapped. All samples collected were analysed according to ISO 6579:2002 (Annex D) and positive samples were serotyped in accordance with Kauffman-White-Le-Minor technique. Our results showed that all different types of samples collected were contaminated with Salmonella (prevalence ranged between 1.5% and 38.6%). The most contaminated samples related with poultry production were: delivery-box liners (32.0%), faeces samples (31.2%), dust samples (25.0%), farming boots (19.7%) and feed from feeders (16.0%). However, the most important risk factors for Salmonella contamination of the flocks at the end of the rearing period were Salmonella status of the house after cleaning and disinfection, Salmonella status of day-old chick flocks and feed from feeders. Twenty-one different serovars were isolated from the samples analysed. The most prevalent were in decreasing order: Salmonella Enteritidis (52.9%), S. Hadar (17.8%), S. Virchow (8.9%) and S. Ohio (5.4%). The study suggested that there are many sources for Salmonella contamination and persistence in broiler production. Hence, the whole production chain needs to be controlled to eradicate the bacteria from primary production.  相似文献   

8.
试验研究了添加不同梯度水苏糖对肉鸡鼠伤寒沙门氏菌攻毒的控制效果。试验选用1日龄体重相近(45.52±1.48)g的健康AA肉鸡公雏72只,随机分为3个处理,设6个重复,每个重复4只。在玉米-大豆浓缩蛋白日粮基础上分别添加0、0.4%和0.8%水平的水苏糖。结果表明:日粮添加水苏糖降低了肉鸡体重;肉鸡肠道沙门氏菌控制效果不显著,第19天时,0.4%水苏糖添加组的大肠杆菌数显著高于其他2组(P<0.05),乳酸菌各处理之间差异不显著;pH值与盲肠指数无差异(P>0.05)。以上研究表明,该梯度水苏糖不能控制肉鸡沙门氏菌感染,对肉鸡无保护作用。  相似文献   

9.
M Padron 《Avian diseases》1990,34(2):463-465
This study was undertaken to demonstrate penetration of Salmonella typhimurium through the eggshell of newly laid broiler hatching eggs. Eggs were challenged either by lightly spraying the bacteria over the blunt end of the egg or by contact with contaminated dry nest litter. Exposure time for both groups was 10 minutes; afterward, all eggs were disinfected and incubated 19 days under normal conditions. Chorioallantoic membranes and yolk sacs were cultured in brain-heart infusion broth on day 19 to demonstrate penetration. Isolation of the bacteria from chorioallantoic membranes and yolk sacs, respectively, were as follows: sprayed group: 100% and 83%; contact group: 59% and 29%. These results showed that although water enhanced S. typhimurium penetration, its presence on the eggshell is not essential for penetration to occur.  相似文献   

10.
Bacteriologic culturing of environmental samples taken from sources such as manure pits and egg belts has been the principal screening tool in programs for identifying commercial laying flocks that have been exposed to Salmonella enteritidis and are thus at risk to produce contaminated eggs. Because airborne dust and aerosols can carry bacteria, air sampling offers a potentially efficient and inexpensive alternative for detecting S. enteritidis in poultry house environments. In the present study, an electrostatic air sampling device was applied to detect S. enteritidis in a room containing experimentally infected, caged laying hens. After oral inoculation of hens with a phage type 13a S. enteritidis strain, air samples were collected onto agar plates with the electrostatic sampling device, an impaction air sampler, and by passive exposure to the settling of aerosols and dust. Even though the floor of the room was cleaned once per week (removing most manure, dust, and feathers), air samples were positive for S. enteritidis for up to 4 wk postinoculation. On the basis of both the number of S. enteritidis colonies observed on incubated agar plates and the frequency of positive results, the efficiency of the electrostatic device was significantly greater than that of the passive exposure plates (especially at short collection intervals) and was similar to that of the far more expensive impaction sampler. The electrostatic device, used for a 3-hr sampling interval, detected airborne S. enteritidis on 75% of agar plates over the 4 wk of the study.  相似文献   

11.
In the study presented here the relationship between the hygienic condition and the concentration of different air contaminants in two pig fattening houses was investigated. Deficiencies in routine cleaning, which were characterized by an increased soiling of animals and stable surfaces with faeces, led to increased concentrations of airborne dust, airborne endotoxins as well as increased numbers of total airborne bacteria and airborne gram-negative bacteria. However these deficiencies were not reflected by the concentration of airborne Clostridium perfringens which were earlier postulated as an indicator of faecal pollution in the air of cattle barns. Furthermore the results of this study were used to discuss advantages and disadvantages of impingement and impaction for the sampling of airborne microorganisms in animal houses.  相似文献   

12.
微生态制剂作为一种新型饲料添加剂已得到广泛的应用。为验证北京伟嘉集团生产的微囊包裹的微生态制剂对肉种鸡在生产性能和蛋品质方面的影响,我们对其应用效果进行观察和分析。结果表明,微生态制剂添加组(试验组)产蛋率和种蛋合格率较对照组分别提高了1.12%和2.27%;蛋品质方面,可提高平均蛋重,试验组较对照组提高了4.75%,达到了极显著水平(P<0.01);蛋白高度和哈氏单位,试验组较对照组分别提高了9.45%(P<0.01)和6.64%(P<0.05),蛋白高度达到极显著水平(P<0.01);而在蛋壳厚度和蛋壳强度方面,试验组与对照组相比差异都不显著(P>0.05)。  相似文献   

13.
Concentration of airborne endotoxins, airborne aerobic bacteria and airborne aerobic gram-negative bacteria were measured in 3 rabbit houses. Further, the species composition of the airborne gram-negative bacterial flora was investigated. The total amount of airborne endotoxin ranged from 22 to 774 EU/m3 (Endotoxin Units/m3). The number of total airborne aerobic bacteria varied between 780 and 20100 CFU/m3, the number of airborne aerobic gram-negative bacteria between 39 and 1030 CFU/m3. Most gram-negative bacterial isolates belonged to the family Enterobacteriaceae with E. coli as primary species. In two rabbit houses also airborne Pasteurella multocida spp. multocida, the most common respiratory pathogen of rabbits, was isolated.  相似文献   

14.
One-day-old broiler chicks were inoculated with volatile fatty acid producing cecal flora from adult chickens. The chicks were divided into four groups and provided 1) no lactose, 2) 2.5% lactose in water, 3) 5% lactose in feed, or 4) 10% lactose in feed, until 10 days of age. All groups were challenged at 3 days of age with 10(6) or 10(8) S. typhimurium. At 10 days, the number of Salmonella in the ceca of the chicks challenged with 10(6) Salmonella was significantly decreased (P less than 0.01) in the groups provided lactose as compared with the controls. A significant decrease (P less than 0.01) in Salmonella numbers occurred in the chicks challenged with 10(8) Salmonella and provided 10% lactose. Providing 2.5% lactose or 5% lactose failed to inhibit Salmonella growth in chicks challenged with 10(8) Salmonella. The pH of the ceca of the groups provided lactose decreased significantly (P less than 0.05) and was accompanied by significant increases (P less than 0.01) in the concentrations of bacteriostatic acetic and propionic acids. Results showed that providing dietary lactose to broiler chicks and inoculation with normal cecal flora decreased cecal pH, increased the concentrations of bacteriostatic volatile fatty acids, and inhibited Salmonella colonization.  相似文献   

15.
利用微生物气溶胶评价鸡舍除尘间的应用效果   总被引:1,自引:0,他引:1  
为研究除尘间对鸡场环境的改善状况,试验以红色荧光蛋白(RFP)基因标记大肠杆菌为指示菌,建立微生物气溶胶传播模型。利用自然沉降法在场区内均匀设置112个采样位点,每个采样位点均进行3次重复收集,以探究除尘间对环境的改善状况。结果显示:试验舍或对照舍散发出的标记菌,均可在场区70%左右布点位置收集到,其中60.94%的布点位置可收集到的标记菌菌落数,试验舍高于对照舍。除尘间内可收集到的平均标记菌菌落数高出对照舍相应位置303.82%(P<0.05)。综合结果,除尘间对舍内排出微生物气溶胶有蓄积作用,便于集中处理,建议在除尘间内加装独立喷淋降尘系统,更有效地减少微生物气溶胶污染。  相似文献   

16.
1. The goal of this study was to evaluate the effects of three chemical treatments on pH and bacterial populations (total aerobic bacteria and gram-negative bacteria) in poultry litter under laboratory conditions. 2. Litter obtained from poultry houses was treated with three chemical treatments (alum, AlCl(3) and FeSO(4)) at the same concentration (8 g/100 g litter), while untreated litter served as a control. The study was conducted for 3 weeks. 3. All of the chemical treatments reduced total aerobic bacteria (22 to 87% of the untreated control) and gram-negative bacteria (63 to 99% of the untreated controls) populations and lowered litter pH values (5.95 to 6.64). However, a significant difference in gram-negative bacteria did not exist among chemical treatments at 0, 1 and 2 weeks. 4. These results suggest that the reduction in total aerobic bacteria and gram-negative bacteria populations is highly related to a decrease in litter pH, and acidifying treatment (alum, AlCl(3) and FeSO(4)) of poultry litter may serve as a means to help the reduction in pathogen populations and to improve economical benefits under commercial production conditions.  相似文献   

17.
Because of recent interest in bacteriophage therapy in poultry, information regarding the interaction of bacteriophages and potential host bacteria in the environment should be collected. The present studies were initiated with a rather typical commercial broiler integrator within the south-central United States to examine environmental Salmonella levels in two broiler complexes, attempt to isolate Salmonella-lytic bacteriophages, and elucidate a possible reason for differing apparent Salmonella prevalence. Significantly (P < 0.05) less Salmonella was isolated from houses in complex 1 (15/44 [34%] Salmonella-positive drag swabs) as compared to houses in complex 2 (22/24 [92%]). A total of seven Salmonella-lytic bacteriophages were isolated from Salmonella-positive environments, and two bacteriophages were isolated from a single Salmonella-negative house. During the initial bacteriophage isolation, individual bacteriophages did not replicate in the Salmonella host isolated from the same environment, and lysis of additional Salmonella hosts relied on high numbers of bacteriophage to be present. This suggests that the presence of these bacteriophages in the environment of a commercial broiler house had little to no effect on the presence of Salmonella. This study highlights the need to find additional bacteriophage sources, more effective isolation methods, and more innovative approaches to using bacteriophages to treat enteric disease.  相似文献   

18.
Prevalence and persistence of Salmonella in broiler chicken flocks.   总被引:2,自引:0,他引:2  
Cecal contents of 2,345 broiler chickens consisting of 28 flocks originated from 12 farms were examined for the prevalence of Salmonella to know the actual status of infection with Salmonella in the chicken flocks. Salmonella was isolated from 336 (14.3%) samples. From these isolates, eight serovars were identified. Of the 336 Salmonella isolates, 242 (72.0%) were serotyped as S. Blockley, 60 (17.9%) S. Hadar, 15 (4.5%) S. Bredeney, nine (2.7%) S. Schwarzengrund, four (1.2%) S. Anatum, three (0.9%) S. Enteritidis, two (0.6%) S. Ohio, and one (0.3%) S. Livingstone. The same serovars of Salmonella were repeatedly found in the chickens from the same farms. S. Typhimurium and S. Enteritidis were detected in pooled broken eggshell samples collected from the hatchery. Analysis of plasmid profiles revealed 11 patterns of S. Blockley and seven patterns of S. Hadar. Strains of the same plasmid profiles of S. Blockley were isolated repeatedly from the same farm over one year after the first isolation.  相似文献   

19.
In Austria an EU-wide baseline survey on the prevalence of Salmonella spp. in broilers organized by the EU commission was conducted from October 2005 to September 2006. The aim of this study was to produce comparable data on the prevalence of Salmonella in broiler flocks and holdings for all member states and for the EU-Commission to set EU-wide targets for the control of Salmonella in the broiler populations. A randomised sampling plan was designed according to EU-commission parameters (p = 50%; CI = 95%, a = 5%). Sampling was carried out regularly throughout the whole year. On every farm one flock was sampled with five pairs of boot swabs and analysed in the lab according to appendix D of ISO 6579 (2002). In Austria, 363 flocks on farms consisting of at least 5000 broilers each were tested. 28 flocks (7.7%) showed infections with Salmonella spp., eight flocks (2.2%) had either S. Enteritidis (six flocks) or S. Typhimurium (two flocks). In detail, S. Enteritidis (1.7%), S. Typhimurium (0.6%), S. Montevideo (4.1%), S. Infantis 0.6%, S. Senftenberg, S. Tennessee and S. Virchow (0.3% each) have been found. Data indicated that the risk of vertical transmission of Salmonella spp. to broiler flocks has almost been kept at bay; however, the risk of horizontal transmission still needs attention. Contamination of feeding stuff, possible persistence, spreading between barns of a farm as well as introduction of Salmonella spp. through individuals or materials are important factors for future control strategies.  相似文献   

20.
1. Deep litter and raised netting flooring systems in broiler houses were compared for their effects on air quality and bird health during an 8-week growing period. 2. Weekly measurements were taken of respirable dust, numbers of airborne microorganisms and concentrations of gaseous pollutants. Airborne fungi and bacteria were identified to species. 3. At the end of the experimental period, randomly sampled bird lungs were examined for the presence of viable microorganisms and for pathological changes. Bird health and performance were monitored throughout the 8 weeks. 4. Respirable dust concentrations and numbers of airborne microorganisms were significantly higher in the litter rooms. The type of floor had no effect on concentrations of gaseous ammonia. 5. Floor type had no significant effect on bird mortality but birds on litter had a slightly better gain:food ratio. However, birds on litter were observed to have a higher incidence of lung damage and more of the birds on litter had viable microorganisms present in the lungs at necropsy.  相似文献   

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