Epidemiological investigations in regard to porcine reproductive and respiratory syndrome (PRRS) in Quebec, Canada. Part 1: biosecurity practices and their geographical distribution in two areas of different swine density

Porcine reproductive and respiratory syndrome virus (PRRSV) is a considerable threat to the swine industry and implementing biosecurity measures is essential for the control of its transmission. The aims of this study were: (1) to describe biosecurity practices in production sites located in a moderate density (MD) and a high density (HD) pig area according to production type; (2) to group sites in different patterns according to their biosecurity practices; and (3) to determine the geographical distribution of sites according to biosecurity patterns. Biosecurity practices were selected based on PRRS epidemiology. A questionnaire was completed on 125 breeding sites (MD=54; HD=71) and 120 growing (HD) sites, between 2005 and 2008. Depending on area and production type, the frequency of biosecurity practices used ranged from 0 to 2% for barrier at site entrance, 0 to 19% for use of shower, 25 to 35% for washing truck between loads of pigs, 51 to 57% for absence of rendering or rendering without access to the site, and 26 to 51% for absence of gilt purchase or purchase with quarantine. Better practices pertaining to entrance protocol (i.e. "no-entry" sign, shower, ≥24 h downtime) were reported more frequently on breeding sites in the MD than the HD area (P<0.05). In the HD area, growing sites had in general a lower level of biosecurity than breeding sites. Using a two-step clustering procedure performed separately for breeding and growing sites, two different patterns were obtained for each production type, which corresponded to a high and low level of biosecurity. For breeding sites, a higher biosecurity level was observed at sites located away from other pig sites, set at more than 300 m from the public road, having higher sow inventory, or being part of an integrated production (P<0.05). Spatial clusters of sites for each biosecurity pattern were detected. This study identified some shortcomings regarding biosecurity that should be addressed before implementing any PRRSV regional control. Vicinity of sites with different biosecurity levels also suggests difficulties in planning priorities of intervention based on geographical distribution of sites.     

Epidemiological investigations in regard to porcine reproductive and respiratory syndrome (PRRS) in Quebec, Canada. Part 2: prevalence and risk factors in breeding sites

Porcine reproductive and respiratory syndrome virus (PRRSV) is a major threat for swine industry and understanding factors involved in its epidemiology is undoubtedly essential for disease control. As a part of a larger project, a cross-sectional study was performed on breeding sites in a moderate density area of swine production in Quebec to estimate the prevalence of PRRSV infected sites and to evaluate if characteristics of sites and biosecurity practices, either as specific measures or as a global score, were associated with PRRSV status. A questionnaire and diagnostic procedures were performed on 54 breeding sites between September 2006 and August 2008. A biosecurity score that had been previously computed using two-step clustering procedure was used, classifying breeding sites into two biosecurity patterns (high vs. low) according to 21 specific biosecurity measures. The apparent prevalence of PRRSV infected sites was 74.0% (95% CI, 60.3-85.0). Univariable and multivariable logistic regression models with robust standard errors adjusting for potential clustering of sites due to same ownership were computed. In a first multivariable model evaluating characteristics of sites and specific biosecurity variables, four main effects were significantly associated (P<0.05) with PRRSV positive status: large pig inventory (OR: 10.7), proximity to closest pig site (OR: 7.3), absence of shower (OR: 8.7) and free access to the main entrance of the site by the rendering truck (OR: 7.0). In a second multivariable model including a global biosecurity score as a surrogate for a specific pattern of biosecurity measures, this score was not retained in the final model. The adjusted population attributable fractions were 16% for the proximity to closest pig site variable, 27% for the absence of shower variable, and 10% for the free access to main entrance of the site by the rendering truck. These two latter biosecurity measures, manageable directly on the site, should be prioritized and be part of any intervention strategy designed for PRRSV control.     

Evaluation of alternative strategies to MERV 16-based air filtration systems for reduction of the risk of airborne spread of porcine reproductive and respiratory syndrome virus

Porcine reproductive and respiratory syndrome (PRRS) is a re-emerging disease of pigs and a growing threat to the global swine industry. For sustainable disease control it is critical to prevent the airborne spread of the etiologic agent, PRRS virus, between pig populations. The application of MERV 16-based air filtration systems to swine facilities in an effort to reduce this risk has been proposed; however, due to the cost and air flow restrictions of such systems the need for alternative strategies has arisen. Therefore, the objective of this study was to evaluate 3 groups of alternative biosecurity strategies for reducing the risk of the airborne spread of PRRSV. Strategies evaluated included mechanical filters, antimicrobial filters and a disinfectant-EVAP (evaporative cooling) system. Results from this study indicate that while alternatives to MERV 16-based biosecurity protocols for protecting farms from the airborne spread of PRRSV are available, further information on their efficacy in the field is needed before conclusions can be drawn.     

Investigating the financial impact of porcine reproductive and respiratory syndrome on smallholder pig farmers in Cambodia

Porcine reproductive and respiratory syndrome (PRRS) was first identified in Cambodia in 2010, causing serious problems on affected farms, although the costs of the disease have not been well defined. The household financial impact of a PRRS outbreak in Cambodia was investigated using partial budget analysis, examining the economic benefit of three proposed interventions: (i) quarterly PRRS vaccine use, (ii) biosecurity implementation, and (iii) implementation of vaccination and biosecurity. The analyses were applied to three farm models: (i) a two-sow breeder; (ii) a five-pig fattener; and (iii) a single-sow, three-pig farrow-to-finish/breeder. Data was derived from a knowledge, attitude, and practice survey of 240 smallholder farmers (61 with pigs) from 16 villages across 5 provinces, plus case studies of 12 farmers selected for more detailed financial analysis. The study indicated that financial losses associated with PRRS were severe, with a 25% mean loss to the annual household income of 61 interviewed farmers. Partial budget analysis identified a strongly positive incentive for vaccination and biosecurity to be implemented in combination, with the highest annual net benefit of USD 357.10 realised by the breeder system. However, due to current scarcity of the PRRS vaccine and its high cost to smallholders, biosecurity interventions may be more cost-effective, especially for low PRRS incidence regions. It was concluded that PRRS critically constrains the profitability of smallholder pig farms and that these findings will assist development of village-level livestock disease risk management programmes that encourage adoption of vaccination and biosecurity practices to enhance farmer livelihoods in Cambodia.     

An assessment of external biosecurity on southern Ontario swine farms and its application to surveillance on a geographic level

Risk-based surveillance is becoming increasingly important in the veterinary and public health fields. It serves as a means of increasing surveillance sensitivity and improving cost-effectiveness in an increasingly resource-limited environment. Our approach for developing a tool for the risk-based geographical surveillance of contagious diseases of swine incorporates information about animal density and external biosecurity practices within swine herds in southern Ontario. The objectives of this study were to group the sample of herds into discrete biosecurity groups, to develop a map of southern Ontario that can be used as a tool in the risk-based geographical surveillance of contagious swine diseases, and to identify significant predictors of biosecurity group membership. A subset of external biosecurity variables was selected for 2-step cluster analysis and latent class analysis (LCA). It was determined that 4 was the best number of groups to describe the data, using both analytical approaches. The authors named these groups: i) high biosecurity herds that were open with respect to replacement animals; ii) high biosecurity herds that were closed with respect to replacement animals; iii) moderate biosecurity herds; and iv) low biosecurity herds. The risk map was developed using information about the geographic distribution of herds in the biosecurity groups, as well as the density of swine sites and of grower-finisher pigs in the study region. Finally, multinomial logistic regression identified heat production units (HPUs), number of incoming pig shipments per month, and herd type as significant predictors of biosecurity group membership. It was concluded that the ability to identify areas of high and low risk for disease may improve the success of surveillance and eradication projects.     

Swine fever: classical swine fever and African swine fever.

Because of the clinical and pathologic similarity to common endemic diseases, introduction of CSFV or ASFV strains of moderate to low virulence represents the greatest risk to North American swine herds. Producers, veterinarians, and diagnosticians should increase their awareness of these devastating diseases and request specific diagnostic testing whenever they are suspected. Production practices that improve biosecurity will reduce the risk of introduction of CSF and ASF and limit the spread if an incursion occurs. Additional resources. The following Web sites contain excellent color photographs that will assist producers and practitioners in identifying clinical signs and gross lesions associated with CSFV and ASFV: http://www.vet.uga.edu/vpp/gray_book/FAD and http://www.pighealth.com. The latter Web site and the OIE Web site (http://www.oie.int) offer updated information on current worldwide epizootics of ASF and CSF and other swine diseases. Details of biosecurity procedures can be found at http://www.agebb.missouri.edu; see publication G2340.     

Multivariate analysis of management and biosecurity practices in smallholder pig farms in Madagascar

A cross-sectional study was carried out in 2005 and 2006 in three geographical areas of Madagascar to investigate and differentiate swine farm management and biosecurity practices in smallholder farming communities. Questionnaire data from a total of 709 pig farms were analysed using multiple factor analysis (MFA) and hierarchical cluster analysis (HCA). Variables describing management and biosecurity practices were organised into five groups: structure of the farm, animal-contacts, person- and vehicle-contacts, feeding, and sanitary aspects. In general, few biosecurity measures were implemented in the pig farms included in the study. Regional differences in management and biosecurity practices emerged from the MFA and were mainly due to, in order of decreasing importance: structure of the farm, sanitary aspects, feeding and animal-contacts and, to a lesser extent, person- and vehicle-contacts. HCA resulted in the differentiation of four distinct types of farms in each of two study areas, Arivonimamo and Marovoay, while no grouping could be identified amongst farms in Ambatondrazaka area. The characterisation of the different types of smallholder pig farms will allow adapting recommendations on husbandry practices and control measures in pig farms of these regions of Madagascar. The development of tailored recommendations is essential for Malagasy smallholders who have limited resources and need to make evidence-based management changes to reduce the risk of contagious diseases in their herds.     

Risk factors associated with Salmonella enterica prevalence in three-site swine production systems in North Carolina, USA

The goal of this study was to identify risk factors associated with increased fecal shedding of Salmonella enterica (SE) in groups of market swine reared in large three-site production units. We conducted an intensive, long-term investigation of potential management and environmental risk factors operating during the growing phase of pig production. Data regarding finisher site characteristics, biosecurity protocols, group growth performance, medication usage, and environmental temperature were collected. Results indicate that SE infection is common. Risk factors were identified at both the finisher site and group level. Biosecurity and hygiene practices (absence of a toilet, more than 2 people present at a finisher site daily, and other domestic species at the site), environmental temperature (winter and spring seasons, increased temperature variability, and below median high temperature the day of sampling), and production performance (above median feed conversion) were associated with elevated SE prevalence. In addition, an association between the floor space allowances per pig at the time of sampling (a measure of the number of pigs sold prior to sampling) was identified, with greater space allowance associated with decreased prevalence. The results of this study identify potential management practices for evaluation for SE control and suggest caution in interpretation of fecal culture results when sampling from different marketing groups in swine production systems.     

Associations between genetics, farm characteristics and clinical disease in field outbreaks of porcine reproductive and respiratory syndrome virus

Porcine reproductive and respiratory syndrome (PRRS) is a disease of domestic swine characterized by exceptionally high clinical variability. This study addresses the question of whether clinical variability in PRRS results from (a) genetic variation among viral isolates and/or (b) variation in management practices among farms on which isolates are found. Genetic data (open reading frame 5 gene sequences) and data on farm characteristics and associated clinical disease signs were collected for 62 PRRS virus (PRRSV) field isolates, representing 52 farms. Clinical disease signs were interrelated — confirming that a true reproductive syndrome exists (involving abortions, infertility in sows, deaths of sows and preweaning mortality).

Pairs of farms experiencing deaths in their sow populations also tended to share viral isolates which were more similar to one another than expected by chance alone. This implies that sow death (one of the more-severe manifestations of PRRS) is under genetic influence. Large herd size was a significant risk factor for the death of sows and for respiratory disease in nursery pigs. All-in–all-out management practices in the nursery were protective against reproductive signs in the sow herd. All-in–all-out management practices in the finishing stages of production were protective against respiratory disease in nursery pigs — but were paradoxically associated with an increased risk of infertility in sows. These results suggest that farm-management practices can also influence which PRRS clinical signs are manifested during an outbreak. In general, signs associated with PRRS appear to result from a combination of genetic factors and herd-management characteristics. The relative contributions of these two influences differ depending on the specific clinical sign in question.     

Factors associated with vesicular stomatitis in animals in the western United States

OBJECTIVE: To compare published recommendations regarding biosecurity practices for various production animal species and classes. DESIGN: Literature review. POPULATION: Educational materials available on the World Wide Web that provided biosecurity recommendations for dairy cattle, beef cattle, small ruminant, swine, and poultry producers. PROCEDURES: Web sites for national producer organizations, university cooperative extension services, and state departments of agriculture were searched to identify educational materials with biosecurity recommendations. RESULTS: A single national organization was selected as representing each animal agriculture commodity group. A total of 53 university Web sites were visited, and 65 publications prepared by university cooperative extension services were identified and evaluated. Web sites for all 50 state departments of agriculture were searched, and 29 were found to have at least 1 publication related to biosecurity practices, for a total of 46 publications. Evaluation of the biosecurity recommendations revealed wide variations by source and within and among commodity groups. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that educational materials for producers contained wide variations in recommended biosecurity practices. It is possible that some producers choose not to implement biosecurity recommendations because of confusion as to the specific recommendations they should follow.     

规模猪场PRRS风险因素分析

猪繁殖与呼吸综合征造成养猪产业巨大经济损失,预防和消除该病已成为世界性难题。本文根据猪繁殖与呼吸综合征流行病学特性,结合规模化猪场生产管理实际,采用风险列举法对规模猪场PRRS传入和场内传播流行的风险因素进行了系统分析。提出规模猪场PRRS风险因素主要包括猪场选址、用品和工具进入、员工和访客进入、活猪运输、饲料运输、死猪处理、粪便管理、猪舍条件、生物传播媒介、引种等外部风险因素和PRRSV状态、管理措施、猪只流动、设施条件、协同病原、猪舍布局等内部风险因素。这为进一步开展规模猪场PRRS风险评估研究,制订科学有效的PRRS风险管理措施奠定了良好基础。     

Biosecurity in 116 Danish fattening swineherds: descriptive results and factor analysis

Biosecurity measures are important for the herd's protection against diseases and also to provide nationwide protection against the introduction of exotic diseases. In this paper, we describe the farmers’ choices and routines regarding biosecurity in Danish fattening herds.

Overall, 116 Danish swine fattening herds in three areas of different pig density were interviewed.

Of these herds, 78% purchased weaners from one sow herd only, whereas 10% purchased from >5 sow herds during 1 year. Large herds (>500 finishers) purchased weaners more often than smaller herds (≤500 finishers). Only two swine producers purchased weaners from a market. Almost all herds (95%) received weaners from one sow herd at one time, and only one herd received from >5 sow herds in one batch. Twenty-one percent did not use an effective barrier between the loading area and the stables when delivering pigs for slaughter. Entry rooms (in which clothing and boots are changed) were common at the farm, and the numbers of visitors were generally low (<10 visitors a year).

Factor analysis was performed to find underlying structures of the biosecurity measures in the herd; four factors were chosen (eigenvalue > 3.10). A site scoring high on factor 1 was a large SPF herd, which received weaners from a single source, had biosecurity requirements for the transport vehicles, and had a high level of biosecurity for visitors. A site scoring high on factor 2 was a multi-site farm, which had personnel working on more than one of the sites, only received weaners from one sow herd, had delivering herds placed close to the participating site, and transported animals themselves. A site scoring high on factor 3 was a site which hired commercial transport for slaughter, was situated far from the abattoir and had a high level of biosecurity when loading pigs. A production site scoring high on factor 4 was a large site, which used all-in/all-out management, washed and disinfected between each group, and purchased many weaners.     

Biosecurity practices on intensive pig production systems in Chile

Chile eradicated classical swine fever (CSF) in April 1998, following a 17-year eradication programme. The authors describe biosecurity levels of pig farms in Chile after the eradication of CSF. A formal survey was administered to 50 large integrated pig farms, which represented almost 60% of the swine population. The main topics on the questionnaire were production, health management, biosecurity, insurance and information about CSF outbreaks in the past. Biosecurity practices were analysed according to the criteria stated by Barcelo and Marco in 1998. A scoring system to measure biosecurity was designed and pig farms were classified according to this score. An adjusted specific measure is discussed as a potential indicator of risk for disease infections. The authors explore associations between biosecurity herd size and insurance policy against CSF.     

Detection of swine torque teno virus in Italian pig herds

Anellovirus is a recently created, floating genus of viruses. Torque teno virus (TTV), the type species in the genus, was first discovered in a human patient with a post-transfusion hepatitis of unknown aetiology. Recently, TTV genetically related to but distinct from those discovered in humans have also been found in animals, including pigs. The aims of this study were to estimate the prevalence of swine TTV in Italian pig herds and some risk factors possibly associated with this infection. Serum samples from 179 healthy pigs from 10 farms located in north-central Italy were tested by polymerase chain reaction for the presence of swine TTV DNA. Viral DNA was found in the sera of 43 pigs (24.0%), coming from eight of the 10 farms examined. Prevalence was significantly higher in finishing herds (40.1%) than in farrow-to-finish herds (11.0%) and did not depend on the size of the herd. Within the finishing herds the prevalence was significantly higher in weaners (57.4%) than in fatteners (22.9%), but this difference was not observed in farrow-to-finish herds. No relationship was observed between the prevalence of swine TTV and the implementation of some general hygiene practices and biosecurity procedures within the herds.     

Trichinae certification in the United States pork industry

Control of Trichinella infection in U.S. pork has traditionally been accomplished by inspection of individual carcasses at slaughter or by post-slaughter processing to inactivate parasites. We propose that an alternative to individual carcass testing or processing can be used when pigs are raised in production systems where risk of exposure to Trichinella spiralis has been mitigated. Declines in prevalence of this parasite in U.S. domestic swine during the last 30 years, coupled with improvements in pork production systems, now allow Trichinella control to be shifted to the farm through implementation of specific pork production practices. Knowledge of risk factors for exposure of swine to T. spiralis was used to develop an objective audit of risk that can be applied to pork production sites. In a pilot study, 461 production site audits were performed by trained veterinary practitioners. The on-farm audit included aspects of farm management, bio-security, feed and feed storage, rodent control programs and general hygiene. Of the 461 production site audits, 450 audits (97.6%) indicated compliance with the required good production practices. These sites are eligible for certification under the U.S. Trichinae Certification Program and will be audited regularly to maintain that status. The described trichinae certification mechanism will establish a process for ensuring the Trichinella safety of swine, and ultimately food products derived from swine, at the production level.     

Estimating the level of disease risk and biosecurity on commercial poultry farms in New Zealand

ABSTRACT

Aims: To collect baseline data on the contact risk pathways and biosecurity practices of commercial poultry farms in New Zealand, investigate the relationship between the farm-level disease contact risks and biosecurity practices, and identify important poultry health concerns of producers.

Methods: A cross-sectional survey of all registered New Zealand commercial poultry operations was conducted in 2016 collecting information on farm demographics, biosecurity practices, and contact risk pathways. Survey responses were used to generate an unweighted subjective disease risk score based on eight risk criteria and a subjective biosecurity score based on the frequency with which producers reported implementing seven biosecurity measures. Producer opinions towards poultry health issues were also determined.

Results: Responses to the survey response were obtained from 120/414 (29.0%) producers, including 57/157 (36.3%) broiler, 33/169 (19.5%) layer, 24/55 (44%) breeder, and 6/32 (19%) other poultry production types. Median disease risk scores differed between production types (p?<?0.001) and were lowest for breeder enterprises. The greatest risk for layer and broiler enterprises was from the potential movement of employees between sheds, and for breeder enterprises was the on- and off-farm movement of goods and services. Median biosecurity scores also differed between production types (p?<?0.001), and were highest for breeder and broiler enterprises. Across all sectors there was no statistical correlation between biosecurity scores and disease risk scores. Producers showed a high level of concern over effectively managing biosecurity measures.

Conclusions: The uptake of biosecurity measures in the commercial poultry farms surveyed was highly variable, with some having very low scores despite significant potential disease contact risks. This may be related to the low prevalence or absence of many important infectious poultry diseases in New Zealand leading farmers to believe there is a limited need to maintain good biosecurity as well as farmer uncertainty around the efficacy of different biosecurity measures. Further research is needed to understand barriers towards biosecurity adoption including evaluating the cost-effectiveness of biosecurity interventions.     

Monitoring porcine reproductive and respiratory syndrome virus infection status in swine herds based on analysis of antibodies in meat juice samples

An indirect ELISA test was developed as a novel tool aimed at monitoring the herd infection status of swine herds. Meat juice samples from pig carcasses were analysed for the presence of antibodies against porcine reproductive and respiratory syndrome virus (PRRSV). A study of samples from herds with known PRRS status was undertaken. The PRRS status of the herds was evaluated based on the analysis of blood samples by another serological test (blocking ELISA) capable of differentiating between infection with PRRSV of the American type and European type. The specificity of the indirect ELISA test on meat juice samples was 0.98. The sensitivity of the test depended on the type of the PRRSV strain involved. The apparent prevalence in herds infected with the American type of PRRSV was 0.44. The apparent prevalence in herds infected with the European type of PRRSV was 0.64. Herd level sampling and herd level criteria for assessing the PRRS status of herds by the new test were developed. Herds were classified as PRRS negative or PRRS seropositive based on 10 meat juice samples collected randomly at slaughter throughout a 3-month-period. Herd PRRS status classification by the indirect ELISA was validated in 47 herds by collection of blood samples from the herds. Eighteen herds were classified as PRRS negative by both test systems. Twenty-nine herds were classified as PRRS seropositive by both test systems. Acceptable herd classification was achieved using this test.     

A preliminary investigation of New Zealand isolates of Pasteurella multocida

Abstract

AIMS: To determine the proportion of residential land parcels with backyard poultry in an urban and urban-rural fringe area of provincial New Zealand. To document key husbandry and biosecurity practices of owners of backyard poultry, and to identify factors that might assist animal health authorities in locating backyard poultry flocks in the event of an infectious disease emergency.

METHODS: A cross-sectional survey was undertaken, in which residents of 449 land parcels in an urban and urban-rural fringe area within and adjacent to the city of Palmerston North, respectively, were visited between February and November 2006. Residents were asked if backyard poultry were kept on the premises. Details recorded for those that kept poultry included the type and number of birds kept, and details of management and biosecurity practices. The geographical distribution of poultry-positive land parcels was assessed for evidence of spatial clustering.

RESULTS: Backyard poultry were kept on 3.5 (95% CI=2.15.0)% of land parcels; 1.6 (95% CI=0.7-3.4)% in the urban area and 18.9 (95% CI= 11.6–29.3)% in the urban-rural fringe area. There were no significant clusters of poultry-positive land parcels in either area. On all poultry-positive parcels birds were allowed, for at least a portion of the day, to range freely over the property. Three poultry-positive land parcels were within a distance of 1 km of a commercial poultry enterprise in the urban-rural fringe area. Most owners of backyard poultry used feed prepared commercially.

CONCLUSIONS: The prevalence of ownership of backyard poultry in this area of New Zealand was low, and varied according to classification of the land, viz urban, or urban-rural fringe. The close proximity of backyard flocks to the single commercial enterprise in the urban-rural fringe area reiterates the importance of strict biosecurity measures on commercial farms. In the event of an infectious disease emergency, it is proposed that a sampling frame of owners of backyard poultry might be rapidly obtained by contacting suppliers of commercial feed.     

三明市某规模化猪场几种疫病的检测情况与分析

通过对三明市某大型猪场进行猪瘟、普通蓝耳病、高致病性蓝耳病、伪狂犬病的病原学和血清学检测,以更好地了解这些疫病在猪场的流行情况,为猪场这几种疫病的防控和净化奠定基础。本次调查分别检测45份后备母猪血清、92份生产母猪血清、13份生产公猪血清,共计150份血清,150份扁桃体样品。通过ELISA方法分别检测了猪瘟、普通蓝耳病、伪狂犬病gE和伪狂犬病gB。荧光定量PCR方法检测了猪瘟、高致病性蓝耳病。结果猪瘟和高致病性蓝耳病病原学阳性率分别为8%和5.3%。一个月后对病原学检测阳性猪采样复查,结果猪瘟阳性率4.6%,高致病性蓝耳病阳性率2.6%。猪瘟免疫抗体合格率93.3%,普通蓝耳病免疫抗体合格率96%,伪狂犬病gB免疫抗体合格率100%,伪狂犬病gE感染抗体2%。生产母猪胎次越多,猪瘟和普通蓝耳病的免疫抗体水平越高。     

酒泉市猪繁殖与呼吸综合征的流行病学监测和分析

为掌握酒泉市猪繁殖与呼吸综合征(PRRS)的流行情况,本试验在酒泉市五个农业县市采集638份样品,采用反转录-聚合酶链式反应(荧光RT-PCR)方法进行核酸检测,对不同地域、不同生长期、不同饲养模式的流行情况进行分析。结果显示,638份样品共检测出PRRS核酸阳性样品29份,PRRS阳性感染率为4.55%。不同地域PRRS阳性感染率介于0-7.95%;屠宰场、规模场、散养户PRRS阳性感染率分别为0、2.96、6.82%;种公猪、育肥猪、仔猪、母猪PRRS阳性感染率分别为0、3.1、5.38、6.36%。结果表明,酒泉市PRRS呈散发流行,规模养殖场标准化高,饲养管理模式先进PRRS阳性感染率低,此病仔猪和母猪更容易感染,本试验将对我市PRRS综合防控提供技术支撑。