Prevalence of Eimeria spp. in Sows at Piglet‐producing Farms in Germany

The prevalence of Eimeria infections was investigated in an initial survey in 54 sow herds of small (five sows) to large (1600 sows) size by random sampling (n = 1204). All sows of four Eimeria‐positive medium‐sized farms (63 or 130 sows) were re‐examined 40–99 days after the first visit. A follow‐up survey over the whole reproductive cycle was subsequently performed in a positive herd of 130 animals where faecal samples of 43 sows were repeatedly collected on seven successive farm visits. In 44 farms (81.5%) parasite stages (eggs of strongylids, Trichuris, Ascaris, Strongyloides, oocysts of Eimeria and Isospora) were identified in sow faeces, strongylids being the most prevalent intestinal parasites (34 farms resembling 63%) followed by Eimeria spp. (28 farms resembling 52%). Of the 1204 random samples collected during the initial survey 8.6% contained Eimeria oocysts. Oocysts of E. polita and E. debliecki were present in each of 25 Eimeria‐positive samples selected for species differentiation. Eimeria suis was diagnosed in 84%, E. scabra in 60%, E. porci in 52%, E. perminuta in 49% and E. spinosa in 20% of these specimens. At the second visit the prevalence rates of Eimeria infections had either increased or decreased. In the follow‐up study Eimeria infections were found to be most frequent (82%) at the service station. At the quarantine unit and the gestation stable 50 and 48% of the 43 sows were Eimeria positive. The lowest prevalence of Eimeria infection was observed in the farrowing unit (14%). With respect to the reproductive state of the sows highest infection rates were seen 2 weeks after weaning (72%) continuously decreasing until 2 weeks after farrowing (14%). A periparturient rise of oocyst excretion was not observed. The infestation rate remained low until 1 week before weaning (16%). Low infection intensities clearly dominated. Clinical disease was not associated with Eimeria infection.     

Isolation of faecal chlamydia from sheep in Britain andtheir characterization by cultural properties

Faeces samples were taken per rectum from sheep on 26 farms in England and Wales and examined for thepresence of chlamydia by culture McCoy cell monolayers. Thirteen of the fars were known to have had abortion outbreaks associated with Chlamydia psittaci (enzootic abortion) and 13 were free of this infection. The chlamydia isolated were characterized by cultural techniques. Chlamydia were isolated from the faeces of lambs on all 26 farms and the prevalence of infection varied from 5–50% on individual farms. There was no significant difference between the proportion of infected lambs on farms where enzootic abortion was present or absent. Lambs first showed infection when they were 3 months old and the prevalence rate of infection increased up to 9 months old. No chlamydia were isolated from the faeces of 316 adult ewes. The chlamydia were identified as enteric rather than abortion type and thus were C. pecorum rather than C. psittaci.     

仔猪球虫病及其防控措施

仔猪球虫病是困扰猪场的主要疾病之一，病原是猪等孢球虫。该病在临床上主要引起1~3周龄仔猪腹泻，造成仔猪生长速度缓慢，断奶体重明显降低。单纯的球虫感染引发的死亡率虽然不高，但遇到产房里其他疾病混合感染时可能出现死亡率的大幅度上升。猪等孢球虫在全世界的猪场感染率都很高，影响了猪场经济效益，但由于死亡率不高往往容易被猪场忽视，特别是在隐性感染症状不明显的猪场。文章回顾了等孢球虫的生活史、国内外的流行病学、检测方法以及控制方案，希望能为广大养猪从业者控制仔猪球虫病提供一个清晰的思路。     

规模化猪场脑心肌炎病毒感染的血清学调查

脑心肌炎病毒(EMCV)可引起猪的脑炎、心肌炎和母猪繁殖障碍,该病已在世界上多个国家暴发和流行。我国对EMCV及其所致疾病的研究工作还处于起步阶段,为了揭示EMCV在我国规模化猪场的感染情况,我们应用酶联免疫吸附试验(ELISA)对2005-2006年间采集自全国13个省市46个规模化猪场的3250份血清样本进行了EMCV抗体检测,结果显示,各省阳性率在39.64%~90%之间,平均抗体阳性率为72%,监测的46个猪场都存在EMCV感染,猪场感染阳性率为100%;对不同生长阶段猪群检测结果表明,EMCV抗体阳性率随猪龄的增长而升高,且不同生长阶段猪抗体阳性率差异极显著;成年公猪的抗体阳性率高于成年母猪。本项调查表明,我国规模化猪场已经普遍感染EMCV,这应引起我国养猪业警惕,并做好该病的综合防控。     

Prevalence and Pathogenicity of Cryptosporidium suis in Pre‐ and Post‐weaned Pigs

A total of 4338 faecal samples, 135 of sows, 3368 of pre‐weaned and 835 of post‐weaned piglets from eight farms in South Bohemia, Czech Republic were collected and examined for Cryptosporidium infection. No sow, but 5.7% pre‐weaned and 24.1% post‐weaned piglets were positive for Cryptosporidium infection. No relationship was found between diarrhoea and Cryptosporidium infection in any of the different age groups (pre‐ and post‐weaned piglets). Four piglets, which were sporadically shedding cryptosporidia in faeces, were necropsied. Neither clinical signs of diarrhoea nor macroscopical changes were found. Histologically, a moderate infection of cryptosporidia was detected in the glandular epithelium along the large intestine, with predisposition to the ansa centralis of the colon. No inflammatory response in the lamina propria was observed. Cryptosporidia were also commonly found in the glandular epithelium of submucosal lymphoglandular complexes in the colon. Cryptosporidium isolates from all farms were identified as Cryptosporidium suis using molecular markers (SSU rRNA). All of the C. suis strains obtained were larger [6.2 (6.0–6.8) × 5.5 (5.3–5.7) μm] than any isolate described so far [4.6 (4.4–4.9) × 4.2 (4.0–4.3) μm] and did not appear to be infective for neonatal BALB/c mice.     

Prevalence of Chlamydia infections in breeding sows and their importance in reproductive failure

To investigate the prevalence of chlamydial infection and their significance for reproductive disorders in sow breeding herds in Germany, blood samples of 1493 pigs were taken for a serological survey by enzyme-linked-immunosorbent-assay (ELISA). Antibodies to Chlamydiae were found in 33% of the samples, in all herds investigated responders could be detected. The rate of seropositive animals in different farms varied from 4.3% to 72.7%. The percentage of positive responders in the farms correlated positively with the occurrence of MMA-syndrome (mastitis, metritis, agalactia), return to oestrus and diseases of the piglets. Also these herds showed less weaned piglets per sow and litter. Comparison of seronegative and seropositive sows within single farms revealed also worse reproductive data for seropositive sows. A significant relationship could be found between farms with a high quota of sero-positive sows and poor hygiene status as well as poultry keeping. As a second step 124 cervical swabs and 9 aborted piglets were investigated for chlamydial antigen by capture-ELISA and polymerase chain reaction (PCR). Using the capture-ELISA for investigation only 3 probes with chlamydial antigen could be detected, however, examination by the more sensible PCR gave positive results in 50% of the probes. 20% of the PCR-positive animals were clinically healthy sows, 80% of the PCR-positive probes originated from sows with reproductive disorders. A significant relationship could be shown between PCR-positive probes and the incidence of abortion and litters with stillborn piglets and piglets with low viability. Swabs from 93 of the 124 sows were investigated as well for other bacterial pathogens of reproductive disorders. A high degree of micro-organisms of different species could be detected in 70% of the samples of sows with reproductive disorders and in 35% of the samples of clinically healthy sows. Species differentiation of the chlamydial antigen positive samples was done by southern blot hybridisation. Herewith C. psittaci could be diagnosed in all positive samples. Additionally 8 probes revealed a mixed infection with C. psittaci and C. trachomatis. The results of the present study show, that the prevalence of chlamydial infections in breeding herds is high and underline the importance of chlamydial infections for reproductive disorders. Single chlamydial infections as well as mixed infections with other pathogens must be considered.     

Prevalence and risk factors associated with intestinal parasites in pigs in Chongqing, China

From 2007 to 2009, the prevalence of intestinal parasites was investigated in intensive and extensive pig farms in Chongqing, China. A total of 2971 samples from both sexes and five age categories (breeding boars, breeding sows, fatteners, growers and weaners) were evaluated by standard methods for the presence of helminth ova and protozoan oocysts, cysts and/or trophozoites. Of the 2971 pigs sampled, 362(12.18%) were infected with Ascaris suum, 301(10.13%) with Trichuris suis, 301(10.13%) with Oesophagostomum spp., 491(16.53%) with Eimeria spp., 149(5.02%) with Isopora suis, 677(22.79%) with Balantidium coli and 196(6.60%) with Cryptosporidium spp. Growers had the highest infection rate while breeding boars had the lowest among the five age categories. B. coli was the most common protozoan in all pig age groups. Pigs infected with multiple parasites were common. Risk factors such as management methods, seasons, ages, etc. can influence the infection rate to a certain degree. This investigation provides relevant data about risk factors for pig farmers, thus allowing them to make more appropriate antiparasitic treatments according to farm conditions and local climate in Chongqing.     

青海省农业区主要猪病的流行病学调查

采用ELISA检测方法和流行病学调查方法，于2004～2005年对青海省互助、湟中、大通、乐都、民和、西宁6县（市）的142个规模养猪场和部分养殖户进行了猪瘟、猪生殖与呼吸综合征、猪圆环病毒2型感染、伪狂犬病等流行状况的调查。结果显示，猪瘟、猪生殖与呼吸综合征、猪圆环病毒2型感染、伪狂犬病在青海省农业区普遍存在，6县（市）之间血清抗体阳性率无明显差异；母猪繁殖障碍覆盖了所有种猪场，后备母猪不发情率约为8．2％，产死胎、木乃伊、弱仔的母猪占繁殖母猪的21％左右；猪瘟仍然是引起当地猪死亡的主要原因。     

广东地区猪传染性萎缩性鼻炎流行病学调查

为了解广东地区猪传染性萎缩性鼻炎(AR)的流行情况,本研究采用细菌分离、鼻甲骨组织形态学测定(TPR值)等方法,对广东各区14个规模在500头母猪的养猪场随机抽样进行AR的流行病学调查。试验统计数据显示,调查的14个猪场均存在AR,平均发病率为58.58%,平均支气管败血波氏杆菌(Bb)感染率为46.74%;抽样猪场中猪的萎缩指数平均数为1.286,萎缩指数标准差为1.871。结果表明,AR在广东省广泛流行,Bb感染率高。     

The prevalence of isospora suis and strongyloides ransomi in suckling piglets in the Netherlands

Summary

Faecal samples from suckling piglets from 113 litters on 25 farms in the Netherlands were examined to study the prevalence of gastrointestinal parasites, in particular Strongyloides ransomi and Isospora suis. S. ransomi was not found but I. suis was demonstrated in 17 of the 25 farms and in 41 out of 77 litters of these farms (53%). No other parasites were found. On the basis of these results, a longitudinal study on the incidence and significance of I. suis was performed on 10 farms (5 litters/farm). I. suis was found on 9 out of 10 farms and in 56% of the litters. Farms differed in infection levels, measured as the numbers of patent litters, and in the onset of patency. Other parasites were only found in faecal samples from the sows and from farrowing pens. These were, in order of prevalence, Balantidium coli, Ascaris suum, Eimeria spinosa, E. debliecki and E. suis.     

Salmonella in breeding pigs: Shedding pattern,transmission of infection and the role of environmental contamination in Irish commercial farrow‐to‐finish herds

This study aimed to provide new insights into the epidemiology of Salmonella in pig production, focusing on potential shedding patterns in breeding pigs throughout a full production cycle and the risk of transmission of infection from the sow to her offspring. A longitudinal study was conducted on five farrow‐to‐finish commercial pig farms. In each herd, shedding of Salmonella in faeces was monitored in breeders through service, gestation and lactation. Swabs of the farrowing room floor and pools of faeces from piglets were collected on two occasions during lactation. Environmental pen swabs were also taken in the weaning and finisher houses. Salmonella isolates were serotyped, tested for antimicrobial resistance (AMR) and typed by Multiple‐Locus Variable number tandem repeat Analysis (MLVA). Shedding by breeding pigs was low in all stages of the production cycle; 5% of sows shed at service, the production stage with highest risk of shedding (p < .01), 1.6% shed during gestation and 2.5% after farrowing. Salmonella was detected in 4% of piglet faecal pools in the second week post‐farrowing and 5% in the fourth week. Serotyping and AMR profiles of Salmonella isolates revealed that strains in sows and gilts were mostly different from strains isolated in weaner and finisher facilities. MLVA typing confirmed that the source of infection in piglets was in most instances the contaminated environment rather than their dam. Based on the typing results, it appears that sows do not pose a major risk in the maintenance and transmission of Salmonella to their progeny but instead the contaminated pen environment is more significant in the perpetuation of the organism on farm.     

Reproductive Performance of Native Pulawska and High Productivity Polish Landrace Sows in the Context of Stress During the Period of Early Pregnancy

Experiments revealed that it is necessary to get rid of genotypes RYR1C/T and RYR1T/T because of problems with meat quality and reproduction of gilts and sows. This phenomenon, however, is of individual nature and is characterized by high variability. The aim of the study was to analyse the influence of stressogenic factors in native Pu?awska and high productivity Polish Landrace breed sows during the period of low pregnancy on reproductive performance and maternal behaviour. Sows in the 2nd reproduction cycle were assigned into groups of five animals as follows: control (C) of RYR1 C/C genotype and experimental (E) of RYR1 C/T genotype. In all, 30 Pu?awska breed sows and 30 PL breed sows were analysed. During the early stage of pregnancy (days 42–84), experimental groups were subjected to the action of stressogenic factors: elevated temperature, noisy and rough treatment of sows by service personnel and immobilization stress. The effect of stressogenic factors was referred to the reproductive performance of sows. Pu?awska and PL breed sows from the experimental groups were subjected to the evaluation of maternal traits on the basis of perinatal behaviour determined with the help of an ethogram. Analysis of the results of reproduction and the behaviour of the sows confirmed the higher resistance to stressogenic factors of the Pu?awska breed. The performed analysis of reproduction and behaviour confirmed that heterozygotic genotypes in the RYR1 locus exhibited less advantageous reproduction, which corroborates the hypothesis about a negative impact of the T allele on swine productivity.     

Prevalence of Chlamydia psittaci in different cat populations in Britain

The prevalence of Chlamydia psittaci infection in household, feral and farm cats in Britain was investigated. Chlamydia were isolated from 30 per cent of conjunctival swabs collected from 753 household cats with conjunctivitis. The prevalence of active chlamydial infection was highest in cats in the age group five weeks to nine months. Males were more frequently infected than females. Cats with chlamydial conjunctivitis usually had antibody titres greater than 1024 as assessed by indirect immunofluorescence. Chlamydia appeared to be endemic in two out of three feral cat colonies on the basis of serological evidence and occasional isolations. Cats on 10 of 22 sheep farms (45 per cent) had serological evidence of chlamydial infection, and this was confirmed on two farms by isolation of the organism from conjunctival and, or, rectal swabs. This is the first survey of infection with Chlamydia psittaci in cat populations in Britain.     

Phenotypic characteristics and virulence genotypes of Trueperella (Arcanobacterium) pyogenes strains isolated from European bison (Bison bonasus)

In a breeding and fattening pig farm an increasing number of cases of abortion and generalized mycobacteriosis at slaughter occurred. Pathological findings compatible with mycobacteriosis, acid-fast organisms in tissues, and isolation of mycobacteria from tissue samples including fetuses, lungs and reproductive organs from sows, genital swabs, mesenteric lymph nodes, and from a sperm sample revealed the cause of the disease. Bacterial cultures were identified as Mycobacterium avium subsp. hominissuis using IS901-/IS1245-specific PCR. Genotyping of selected isolates from animals as well as from their environment by MIRU-VNTR analysis showed that the herd was infected with one single outbreak strain. The same genotype was also isolated from pigs of two other farms which showed comparable symptoms and were in direct contact with the index farm as well as from their environment. Immunological host responses detected by tuberculin skin test and ELISA gave positive results at herd level only. Despite the detection of other potential pathogens mycobacteria were regarded as the causative agent of the reproductive disorders. To our knowledge this is the first report of an epidemic mycobacterial infection in a pig holding associated with reproductive disorders, which could be attributed to one single virulent strain, and the first report of detection of M. avium subsp. hominissuis in pig sperm.     

Prevalence and age-related infection of Cryptosporidium suis, C. muris and Cryptosporidium pig genotype II in pigs on a farm complex in the Czech Republic

A total of 413 pig faecal samples were collected from pre-weaners (119), starters (131), pre-growers (123) and sows (40) from a farm with a closed breeding system segmented into two breeding complexes and a growing complex in the region of Vysočina, Czech Republic and screened for the presence of Cryptosporidium using staining methods and genotyping (SSU rRNA). Cryptosporidium oocysts were detected by microscopy in the faeces of 21.1% of the samples (87/413). Sequence analyses and RFLP identified C. suis in 44, Cryptosporidium pig genotype II in 23 and C. muris in 2 samples. No mixed infections were found.Pigs under 7 weeks of age were infected with C. suis only. Cryptosporidium pig genotype II was found in animals from 7 weeks of age. No relationship was found between diarrhoea and any Cryptosporidium infection in any of the different age groups (P < 0.05). The pre-weaned pigs shed significantly more Cryptosporidium oocysts than older pigs and it was associated with C. suis infection.     

A Survey of Gastrointestinal Pig Parasites on Free-range,Organic and Conventional Pig Farms in The Netherlands

The prevalence of gastrointestinal parasites in suckling piglets, weaners, fattening pigs and sows was studied from November 2001 to October 2002 on 16 free-range farms (FRF), 11 organic farms (OF) and 9 conventional farms (CF) by means of faecal examinations of composite samples. Each farm was visited four times with a 3-month interval. Infections with coccidia were found on 43.8% of the FRF, 90.9% of the OF and 66.7% of the CF. Sows had the highest prevalence, particularly on FRF (87.5%) and OF (80%).Ascaris suum was present on 50% of the FRF, 72.7% of the OF and 11.1% of the CF, whereas fattening pigs on FRF (42.9%) and OF (54.5%) had the highest prevalence.Oesophagostomum spp. were observed on 25% of the FRF, 27.2% of the OF and 22.2% of the CF. The infection was most prevalent in the sows on all farm types: 37.5% on FRF, 30% on OF and 22.2% on CF.Trichuris suis was found on 37.5% of the FRF, 36.4% of the OF and 11.1% of the CF. Again, this infection was most prevalent in the sows, particularly on the FRF (50%) and OF (30%). No other gastrointestinal parasite species were found and no clinical signs were observed. No seasonal trends could be distinguished. In many cases, when an age group on a farm was positive for a certain parasite, it remained so during the whole study. This indicates that this parasite was really ‘endemic’ on that farm. The results of this study demonstrate that the prevalence of helminth infections of pigs on farms with outdoor facilities is higher than in pigs on conventional farms.     

集约化养猪场嗜流产衣原体病流行状况的初步调查

本试验对北京郊区5个规模化猪场断奶仔猪、育成猪、育肥猪和怀孕母猪采集血清共507份,同时采集密切接触饲养人员、仔猪、育肥猪的喉头拭子、母猪阴道拭子及公猪的精液共183份。分别使用间接血凝诊断试剂盒、法国ELISA试剂盒检测抗体;利用直接荧光染色法检测抗原,包括166份猪喉头拭子、阴道拭子和精液以及17份饲养人员喉头拭子。结果发现间接血凝诊断试剂盒、ELISA试剂盒抗体阳性率分别为4.14%和2.17%;抗原平均阳性率为14.8%,其中精液阳性率达到37.5%,母猪阴道拭子阳性率为27.5%,饲养人员阳性率为23.5%。本试验证实北京郊区猪嗜流产衣原体在种公猪、母猪群和饲养员呈高流行趋势。同时研究结果显示,5个被调查的规模化猪场嗜流产衣原体抗体阳性率显著低于有报道的其他省市,这与间接血凝诊断试剂盒检测结果高于ELISA试剂有关。针对发现的问题,必须采取有效措施控制种公猪精液污染衣原体现象,阻断向母猪和饲养人员传播,以降低人兽共患病发生的风险。     

Evaluation of different laboratory methods for diagnosis of pig chlamydiosis in Lithuania

Pig chlamydiosis is antrophozoonosis caused by Chlamydophila abortus. Chlamydias (C type) are widely found in nature and can infect humans, domestic and wild mammals, and 139 types of birds. The peculiar feature of chlamydias is the tropism to different tissues, organs and organisms. In 2502 pig blood sera tests from Lithuanian farms, anti-chlamydia complement binding (CB) antibodies were detected in 192 cases (7.7%). Serological tests showed the following (C type) chlamydia bearing regions: 22.0% Mazeikiai district, 17.2%--Kaisiadorys district, 13.5%--Panevezys district, 12.3%--Vilkaviskis district. Rare incidence of the disease was found in Siauliai district 1,2% and Klaipeda district 2.5% farms. The highest antibody titers in blood serum tests were found in Joint Stock Company (JSC) "Krekenava" and "Vejine", i.e. 1:128 and 1:64, respectively. The following methods for the study of pig chlamydiosis were used and comparatively evaluated: complement binding reaction (CBR), direct immunofluorescence (DIF), imunoenzyme assay (IEA), indirect immunofluorescense (IIF), micro immunofluorescense (MIF), polymerase chain reaction (PCR) and cell culture (CC) test. PCR method was found to be more sensitive and reliable compared to imunoenzyme assay, but the latter is more economic especially for screaning. In pigs with the clinically expressed symptoms, 108 pigs infected with chlamydia were detected. CB assay revealed the infection rate from 3.4% to 7.9% in piglets, sows and boars. The highest level of chlamydia infection was detected in fatteners (17.6%). Seroepizootic study of pig chlamydiosis revealed the different infection rate in the animals investigated. The highest chlamydia infection risk is in winter (10.4%) and the lowest--in summer (2.8%).     

Serovar profiling of Haemophilus parasuis on Australian farms by sampling live pigs

Objective Investigate the diversity of serovars of Haemophilus parasuis (Hps) present in Australian pig herds. Design Nasal swabs were used to obtain multiple isolates of Hps, which were grouped first by genotyping and then by serotyping representative isolates. Procedure Swabs were taken from the nasal cavity of just-weaned healthy pigs from multiparous sows on 12 farms and from post-weaned pigs of multiparous sows on 1 farm. On 5 of the 13 farms, nasal swabs were also obtained from pigs showing clinical signs suggestive of Glässer's disease. On a further 7 farms, nasal swabs were obtained only from pigs with clinical signs suggestive of Glässer's disease. Results A total of 556 Hps isolates were genotyped, and 150 isolates were serotyped. Hps was detected on 19 of the 20 farms, including 2 farms with a long history of freedom from Glässer's disease. Isolates of Hps belonging to serovars regarded as potentially pathogenic were obtained from healthy pigs at weaning on 8 of the 10 farms with a history of Glässer's disease outbreaks. Sampling 213 sick pigs yielded 115 isolates of Hps, 99 of which belonged to serovars that were either potentially pathogenic or of unknown pathogenicity. Only 16 isolates from these 213 sick pigs were of a serovar known to be non-pathogenic. Conclusion Healthy pigs contain a range of Hps serovars, even on farms free of Glässer's disease. Nasal swabbing of both healthy and sick pigs seems a useful method of serovar profiling of farms.     

关于三元母猪种用价值和改善措施的探讨

非洲猪瘟背景下,猪场面临两大难题,一是安全问题,二是种源问题。通过不断提升生物安全等级能够有效保障猪场安全,但种源问题却一时难以解决。在这种特殊背景下,部分猪场开始大胆创新的将三元母猪作为种源进行生产。但是,国内外关于三元母猪种用的资料文献几乎没有,无法形成有效的借鉴。一时之间,关于三元母猪究竟有没有种用价值和如何提高其种用价值成为养猪业的热门话题。文章从三元母猪种用价值、种用劣势和改善措施三个方面进行深入剖析和探讨,旨在为猪场了解和使用三元母猪提供参考。