如何降低家禽沙门氏菌感染的风险(续完)

3预防沙门氏菌传播的措施3.1卫生和消毒在引进新一批鸡群前,所有鸡舍和器具必须进行清洁消毒,特别是在前一批鸡群为沙门氏菌阳性的情况下,清洁消毒就更有必要。卫生措施的有效性可通过严格的细菌学定量检测验证,要求肠道细     

Administration of autochthonous intestinal microflora--a method to prevent Salmonella infections in poultry

Administration of autochthonous intestinal microflora to chicks during the early period after hatching (Competitive Exclusion) is a widely accepted prophylactic method to control Salmonella infections in poultry. The method of competitive exclusion consists in an administration of intestinal flora from healthy adult birds to chicks during the first hours or days of their life. Use of competitive exclusion cultures will considerably enhance resistance to all Salmonella serovars colonising the chicken intestine and reduce shedding of salmonellas by infected animals. However, sole use of this method does not completely prevent Salmonella colonisation of the animals nor elimination of the agents from poultry flocks. At present, only complex competitive exclusion cultures whose composition has not been defined are capable of inducing an adequately high and reproducible efficacy. Effective preparations with a defined composition have not yet been developed because knowledge of the mechanisms of action of the competitive exclusion cultures as well as the effective species of the various bacterial genera is still inadequate. Since in approval procedures, the competitive exclusion cultures with a non-defined composition can neither be classified as medicines nor feed additives nor vaccines, WHO has proposed to establish the product category "Normal Gut Flora" (WHO, 1994). Basic prerequisites for an effective reduction of non-host-adapted Salmonella serovars in, or their elimination from poultry flocks are the performance and assurance of effective hygienic measures. Like the methods of immunisation using live or inactivated Salmonella vaccines in poultry, the method of competitive exclusion constitutes an additional prophylactic method that may be applied directly in the animal to enhance its resistance to Salmonella infection.     

控制鸡的支原体感染

由于支原体感染事件在世界各地的鸡群中接连发生,因而有必要对该病加以控制。对蛋种鸡、后备母鸡和肉鸡施予适当的控制方法后,就能够成功地减少因支原体感染造成的经济损失。     

"养鸡生产中沙门氏菌病的预防与控制策略"专栏(四)沙门氏杆菌和弯曲杆菌在家禽群体中的动态变化特征

难道我们不想掌控自身命运吗?虽然这是-个很广博的问题,但如果你在考虑幼龄肉鸡群沙门氏菌感染这个特定话题以及考虑它与人食源性疾病可能的关系时,这个问题就具有特殊的意义.出席美国国家家禽改良计划(the National Poultry Improvement Plan,NPIP)第40届年会(两年一次)的大多数代表,在投票是否采用美国肉鸡扩繁群肠炎沙门氏菌监测方案时,对该特殊问题给出了肯定回答.     

Immune mechanisms in infections of poultry

Resistance to infectious agents may depend upon innate mechanisms or acquired immune responses. Inflammation, phagocytosis, cell-mediated immunity and antibodies are components of a complex reaction which result either in resistance or in susceptibility. Most infectious organisms stimulate immune responses within every compartment of the immune system. In rather few infections of poultry, it is possible to pinpoint a limited number of immune reactions that are primarily responsible for resistance. In some situations, autoimmunity may contribute to the pathology associated with infections.     

饲料添加剂可降低家禽沙门氏菌的感染率

对家禽生产者而言,沙门氏菌出现在家禽中绝对是一件高成本的事故。饲料添加剂能通过多种方式来降低沙门氏菌感染的风险。精油化合物的抗菌特性会使家禽具有良好的健康状况,并可确保消费者的食品安全。     

E-nose identification of Salmonella enterica in poultry manure

1. A DiagNose II electronic nose (e-nose) system was tested to evaluate the performance of such systems in the detection of the Salmonella enterica pathogen in poultry manure.

2. To build a database, poultry manure samples were collected from 7 broiler houses, samples were homogenised, and subdivided into 4 portions. One portion was left as is; the other three portions were artificially infected with S. enterica.

3. An artificial neural network (ANN) model was developed and validated using the developed database.

4. In order to test the performance of DiagNose II and the ANN model, 16 manure samples were collected from 6 different broiler houses and tested using these two systems.

5. The results showed that DiagNose II was able to classify manure samples correctly as infected or non-infected based on the ANN model developed with a 94% level of accuracy.

     

Salmonella contamination of poultry flocks in The Netherlands

The contamination of poultry in the Netherlands with Salmonella enteritidis was tested. For this, different methods (detection of S. enteritidis in faecal samples of 25 g; detection of S. enteritidis in cloacal swabs; detection of S. enteritidis by serological testing of antibodies in serum) were compared for their efficiency to detect S. enteritidis in flocks of poultry. Testing of faecal samples clearly yielded the best results. This method was used in a transmission study, in which 14 flocks descending from a contaminated primary mother flock were screened for the presence of S. enteritidis. The method was also used for screening 49 flocks of laying hens and 52 flocks of broiler chickens throughout the Netherlands. From the transmission study it became clear that S. enteritidis, phage type 2 (Dutch phage set) was isolated both from the mother flock and from five of the descendent flocks. Screening of poultry flocks for the presence of salmonella revealed that salmonella was present in 47% of the layer flocks and in 94% of the broiler flocks. S. enteritidis was isolated from 15% of the flocks screened.     

Four multistate outbreaks of human Salmonella infections associated with live poultry contact, United States, 2009

Outbreaks of human salmonellosis associated with live poultry contact have been reported since 1955. Multiple Salmonella serotypes have been associated with these outbreaks, and specific outbreak strains have been repeatedly linked to single hatcheries over multiple years. During 2009, four multistate outbreaks of human Salmonella infections associated with direct and indirect exposure to live poultry purchased from mail-order hatcheries and agricultural feed stores were identified, resulting in 165 culture-confirmed cases in 30 states. This report describes the epidemiologic, environmental and laboratory investigations conducted by state and local health departments, state departments of agriculture, the U.S. Department of Agriculture (USDA), Animal and Plant Health Inspection Service (APHIS), National Poultry Improvement Plan (NPIP) and National Veterinary Services Laboratories (NVSL), and the Centers for Disease Control and Prevention (CDC). Case-patients were identified through PulseNet, the national molecular subtyping network for foodborne disease surveillance, and interviewed using the CDC standard live poultry contact questionnaire that asks about poultry-related exposures during the 7 days before illness onset. These outbreaks highlight the need to focus efforts on strategies to decrease and prevent human illness associated with live poultry contact through comprehensive interventions at the mail-order hatchery, agricultural feed store and consumer levels. Additional consumer education and interventions at mail-order hatcheries and venues where live poultry are sold, including agricultural feed stores, are necessary to prevent transmission of Salmonella from poultry to humans.     

Use of delayed secondary enrichment for the isolation of Salmonella in poultry and poultry environments

A conventional method of isolating Salmonella was compared with isolation using novobiocin-supplemented plating media and delayed secondary enrichment (DSE). The DSE greatly increased the ability to isolate Salmonella from poultry and environmental samples. Four hundred sixty-four isolations of Salmonella were made from a total of 4377 cultures (11%). Two hundred sixty-nine (58%) isolations of Salmonella were made following the 24-hour incubation; of these, 43 (9%) isolates were isolated only at this time. In comparison, a total of 421 (91%) Salmonella were isolated by DSE, of which 195 isolates (42%) were isolated only with DSE. The addition of novobiocin to the selective plating medium increased the isolation rate for Salmonella and reduced the level of contaminating bacteria growing on the plate.     

减少沙门氏菌在猪场传播的机会

猪随时随地都可能感染沙门氏菌,无论是在配种过程中,还是断奶时,抑或是在屠宰场。研究表明,尽管很难将沙门氏菌从猪场中根除,但还是有机会减少其在猪场中的传染。     

Control of avian mycoplasma infections in commercial poultry

Control of pathogenic avian mycoplasmas can consist of one of three general approaches: Maintaining flocks free of infection, medication, or vaccination. Maintaining flocks free of pathogenic mycoplasmas consists of maintaining replacements from mycoplasma-free sources in a single-age, all-in all-out management system. Good biosecurity and an effective monitoring system are necessary aspects of this program. Medication can be very useful in preventing clinical signs and lesions, as well as economic losses, but cannot be used to eliminate infection from a flock and is therefore not a satisfactory long-term solution. Vaccination against Mycoplasma gallisepticum (MG) or M. synoviae (MS) can be a useful long-term solution in situations where maintaining flocks free of infection is not feasible, especially on multi-age commercial egg production sites.