The purpose of the study was to gain knowledge about the prevalence and identity of rumen flukes (RF) in cattle and sheep in the Netherlands. Routine faecal examinations of diagnostic submissions between May 2009 and September 2014 showed a mean annual herd or flock RF prevalence of 15.8% for cattle and 8.0% for sheep. Prevalence in cattle was higher after 2012 than before, which may reflect a change in detection method as well as an increase in true prevalence. During November and December 2014, an abattoir survey was conducted to allow for scoring of rumen fluke burden and to obtain specimens for molecular species characterization. Over 8 visits to 5 abattoirs in areas deemed to pose a high risk for trematode infection, 116 cows and 41 sheep from 27 herds and 10 flocks were examined. Prevalence of RF was higher in beef cattle than in dairy cattle and higher in cattle than in sheep. Median fluke burden was >100 specimens per animal for most positive animals. Using a semi-quantitative RF density score as a gold standard, sensitivity and specificity of a modified quantitative Dorsman egg counting method were estimated at 82.6% and 83.3%, respectively. Of 14 collected adult rumen flukes, twelve (8 bovine and 4 ovine specimens) were identified as Calicophoron daubneyi. The other two, of bovine origin, were identified as Paramphistomum leydeni, which was unexpected as in other European countries all recently collected rumen flukes in both cattle and sheep were identified as C. daubneyi. The findings implicate that multiple rumen fluke species, intermediate host species and transmission cycles may play a role in rumen fluke infections in the Netherlands.

In the period from 2005 to 2009, Coxiella burnetii was a cause of abortion waves at 28 dairy goat farms and 2 dairy sheep farms in the Netherlands. Two years after the first abortion waves, a large human Q fever outbreak started mainly in the same region, and aborting small ruminants were regarded as most probable source. To distinguish between infected and noninfected herds, a surveillance program started in October 2009, based on PCR testing of bulk tank milk (BTM) samples, which had never been described before. The aim of this study was to analyze the effectiveness of this surveillance program and to evaluate both the effect of culling of pregnant dairy goats on positive farms and of vaccination on BTM results. Bulk tank milk samples were tested for C. burnetii DNA using a real-time PCR, and results were analyzed in relation to vaccination, culling, and notifiable (officially reported to government) C. burnetii abortion records. In spring and autumn, BTM samples were also tested for antibodies using an ELISA, and results were evaluated in relation to the compulsory vaccination campaign. Between October 2009 and April 2014, 1,660 (5.6%) out of 29,875 BTM samples from 401 dairy goat farms tested positive for C. burnetii DNA. The percentage of positive samples dropped from 20.5% in 2009 to 0.3% in 2014. In a multivariable model, significantly higher odds of being PCR positive in the BTM surveillance program were found in farms of which all pregnant dairy goats were culled. Additionally, the risk for C. burnetii BTM PCR positivity significantly decreased after multiple vaccinations. Bulk tank milk ELISA results were significantly higher after vaccination than before. The ELISA results were higher after multiple vaccinations compared with a single vaccination, and ELISA results on officially declared infected farms were significantly higher compared with noninfected farms. In conclusion, BTM surveillance is an effective and useful tool to detect C. burnetii shedding dairy goat herds and to monitor a Q fever outbreak, and thus the effect of implemented measures.

In a sheep farm in the Netherlands with a suspected Haemonchus contortus resistance to monepantel (Zolvix®, Novartis Animal Health), a fecal egg count reduction test was carried out in two groups of lambs, according to the method of the World Association for the Advancement of Veterinary Parasitology. Group 1 was the untreated control group, and group 2 was treated with monepantel at the manufacturer's recommended dose rate. Efficacy of treatment with monepantel was 0%. Larval identification of pre- and post-treatment coprocultures revealed 100% H. contortus larvae. On this farm, after a perceived reduction in efficacy of ivermectin and doramectin, the sheep farmer started using monepantel in July 2012, and since then, monepantel was used as the sole anthelmintic. Breeding sheep were treated twice each year in 2013 and 2014, and lambs two times in 2012, four times in 2013, and three times in 2014, before monepantel resistance was suspected, and confirmed three weeks later. Although the frequency of monepantel treatments on this farm was relatively high with treatments on thirteen separate occasions in two years time, possibly establishing favorable conditions for a competitive advantage for resistant H. contortus, it is remarkable that resistance to monepantel was established in such a very short period. This study confirms, to the best of our knowledge, the first case of H. contortus resistance to monepantel occurring in the field.

Benzimidazole resistance in sheep was first described in 1964 (Drudge and others 1964). Nowadays, multiple anthelmintic resistance is of major concern for the sheep and goat industry (Sargison 2012). In Europe, resistance to moxidectin (MOX) has been described in Germany in Haemonchus contortus (Scheuerle and others 2009), in the UK in Teladorsagia circumcincta (Wilson and Sargison 2007, Sargison and others 2010), and recently to long-acting injectable MOX in northwestern Spain (Martinez-Valladares and others 2013), and is not as common as resistance to ivermectin (IVM) and doramectin (DRM) (Maingi and others 1997, Ambrosini 2000, Sargison and others 2001, Cernanska and others 2006, Borgsteede and others 2007). On a Dutch sheep farm, MOX resistance was suspected, and a study was conducted aiming (1) to investigate this suspected case, (2) to simultaneously test the efficacy of DRM, monepantel (MPL), fenbendazole (FBZ) and levamisole/triclabendazole (LEV/TCBZ) and (3) to identify the genus and species of nematodes before and after treatment by larval culture. On a farm with 700 breeding ewes, around 150 ewe lambs were purchased annually as replacements. On arrival, these lambs were treated with MOX (Cydectin 0.1 per cent Oral Solution for Sheep, Zoetis BV), and subsequently placed onto low-contaminated pastures with a pre-existing population of the farm's endemic worm population. In preceding years, all breeding ewes were treated with MOX (Cydectin 0.1 per cent Oral Solution for Sheep, Zoetis BV) directly after lambing, and with DRM (Dectomax Solution for Injection, Zoetis BV) six weeks prior to breeding. Lambs were treated …

Q fever is a zoonotic disease, caused by the obligate intracellular bacterium Coxiella burnetii. Between 2007 and 2010, Q fever has been a major public health concern in the Netherlands, with almost 3500 human cases reported and dairy goats considered to be the most probable source. At the end of 2009, the Dutch government decided to cull all pregnant dairy sheep and dairy goats based on bulk tank milk C. burnetii positive farms, aiming to preventing shedding and to reducing environmental contamination. On bulk tank milk C. burnetii PCR positive farms, a life-time breeding ban was implemented for all remaining non-pregnant small ruminants. This study describes test results on a bulk tank milk C. burnetii PCR positive dairy goat farm on which all goats had been vaccinated against Q fever with an inactivated phase one vaccine since 2008. All pregnant dairy goats of this farm were culled in 2010, after which bulk tank milk was negative in the C. burnetii PCR. One year later, however, this farm became bulk tank milk C. burnetii PCR positive again. From all lactating animals on the farm (n = 350), individual milk samples were collected and tested using a commercial real-time PCR assay. Individual milk samples from five dairy goats appeared to be C. burnetii PCR positive. These positive goats had been born on the farm between 2002 and 2006. At postmortem examination, out of 33 mostly tissue samples per animal, only milk and mammary tissue samples were C. burnetii PCR positive. Moreover, immunohistochemical examination did not reveal the source of C. burnetii. After culling of these C. burnetii PCR milk positive animals, the bulk tank milk remained negative in C. burnetii PCR until the end of the observation period. The results indicate that vaccination of Q fever infected dairy goat farms does not completely prevent intermittent shedding of C. burnetii in probably previously infected goats. Further research is needed to investigate how and where C. burnetii multiplies in such intermittently shedding animals.

In 2007, a human Q fever epidemic started, mainly in the south eastern part of The Netherlands with a suspected indirect relation to dairy goats, and, to a lesser degree, to dairy sheep. This article describes the Q fever prevalences in Dutch dairy goat and dairy sheep bulk tank milk (BTM) samples, using a real-time (RT) PCR and ELISA. Results of BTM PCR and ELISA were compared with the serological status of individual animals, and correlations with a history of Q fever abortion were determined. When compared with ELISA results, the optimal cut-off value for the RT-PCR was 100 bacteria/ml. In 2008, there were 392 farms with more than 200 dairy goats, of which 292 submitted a BTM sample. Of these samples, 96 (32.9 per cent) were PCR positive and 87 (29.8 per cent) were ELISA positive. All farms with a history of Q fever abortion (n=17) were ELISA positive, 16 out of 17 were also PCR positive. BTM PCR or ELISA positive farms had significantly higher within-herd seroprevalences than BTM negative farms. In the south eastern provinces, the area where the human Q fever outbreak started in 2007, a significantly larger proportion of the BTM samples was PCR and ELISA positive compared to the rest of The Netherlands. None of the BTM samples from dairy sheep farms (n=16) were PCR positive but three of these farms were ELISA positive. The higher percentage of BTM positive farms in the area where the human Q fever outbreak started, supports the suspected relation between human cases and infected dairy goat farms.

At the end of 2007, the first year of what later turned out to be one of the largest Q fever outbreaks in the world with ultimately almost 3500 human patients notified in three years time, daily goats were suspected to be the possible cause. However, current information on the Q fever prevalence in small ruminants in The Netherlands was lacking.A serological survey, using an indirect ELISA, was carried out in 15,186 sheep and goats in The Netherlands in 2008. In total, 2.4% (95% CI: 2.2-2.7) of the sheep and 7.8% (95% CI: 6.9-8.8) of the goats was seropositive for antibodies against Coxiella burnetii. In 14.5% (95% CI: 12.5-16.5) of the sheep flocks and 17.9% (95% CI: 14.2-21.5) of the goat herds at least one seropositive animal was found. In sheep flocks with at least one seropositive sheep, the within herd seroprevalence was 14.8% (95% CI: 12.6-17.0). In goat herds with at least one seropositive goat, the within herd seroprevalence was 29.0% (95% CI: 24.6-333).The seropositive sheep were equally distributed across the country. The seroprevalence in goats in the south-eastern part of The Netherlands, the area where most of the human Q fever cases were notified, was significantly higher than the seroprevalence in goats in the rest of The Netherlands. Dairy sheep and dairy goats had a significantly higher chance of being seropositive than non-dairy sheep and goats. During pregnancy and in the per-parturient period, small ruminants tested significantly more often seropositive than in the early- or non-pregnant period.The seroprevalence as well as the true prevalence among small ruminants in The Netherlands were lower than prevalences reported elsewhere. The seroprevalence among sheep was also lower than reported in an earlier Dutch study in 1987. The Q fever seroprevalence was highest in pregnant and periparturient dairy goats in the south-eastern part of The Netherlands, which coincides with the region with the highest human incidence of Q fever. (C) 2012 Elsevier B.V. All rights reserved.

In Autumn 2009, a faecal egg count reduction test (FERCT) was carried out on three sheep farms. Groups of 8-11 lambs were treated with ivermectin or moxidectin, with a 14-day interval between treatment and sampling. Ivermectin resistance was present on all three farms. Treatment with ivermectin resulted in a reduction in faecal egg numbers of 94.6%, 63%, and 59%. On two farms, 14 days after treatment pooled faecal samples yielded predominantly larvae of Hamonchus contortus (100% and 98%, respectively). On the third farm, H. contortus and (probably) Teladorsagia circumcincta were resistant to ivermectin (64% and 36% of the larvae, respectively). Treatment with moxidectin resulted in a 100% reduction in egg output in sheep on all three farms. More sensitive culture techniques failed to detect any larvae in samples taken from two farms, but a few Ostertagia-type larvae, probably of T. circumcincta, were detected in samples from the third farm. It can be concluded that gastrointestinal nematodes in sheep from these three farms were resistant to ivermectin, whereas resistance to moxidectin was not detected.

In 1862, the veterinarian Loman reported the first sheep in The Netherlands with symptoms associated with lentiviral infection, although at the time the symptoms were ascribed to ovine progressive pneumonia. In the following century, similar cases were reported by South African, French, American, and Icelandic researchers. Extensive research into the pathology, aetiology, and epidemiology of this slowly progressive and ultimately fatal disease was initiated in several countries, including the Netherlands. Studies of the causative agents--maedi visna virus (MVV) in sheep and caprine arthritis encephalitis virus (CAEV) in goats, comprising the heterogeneous group of the small ruminant lentiviruses (SRLV)--prompted the development of diagnostic methods and the initiation of disease control programmes in many European countries including the Netherlands, as a pioneer in 1982, and in the U.S.A. and Canada.

A SRLV-free sheep flock incurred infection which led to an SRLV infection rate of over 50% of the ewes (34/64) within a 30 months period, indicating that environmental conditions were favourable to transmission. An intensive regimen of sampling at short intervals and testing for SRLV antibodies and proviral DNA combined with strict management was implemented for the entire flock, lambs and yearlings included. This resulted in eradication of the infection within two testing and culling rounds with a 3 months interval. The additional value of the proviral DNA detection by PCR in identifying infected animals was clear in that nine infected animals were found that would have been missed if tested by serology alone. PCR also saved two lambs from being culled; they were sero-positive probably due to maternal antibodies, but not infected.

The objective of the study was to evaluate the diagnostic performances of the ELITEST-MVV ELISA for detection of antibodies against small ruminant lentiviruses and of two recently published PCRs for the detection of proviral DNA of SRLV in blood and corresponding individual milk samples. In addition, the feasibility of bulk milk testing was investigated by titrating ELISA positive pooled milk samples in negative milk, and by investigating bulk milk samples by ELISA and PCR in relation to the SRLV-status of the flocks. The results show that plasma and milk are suitable replacements for serum. For sheep, both PCRs showed a better diagnostic performance than for goats. ELISA results for bulk milk samples were promising with a putative detection limit of <3% within-herd prevalence using 1/10 pre-diluted samples and even <1% within-herd prevalence when samples were tested undiluted. In a panel of 249 bulk milk samples, all samples from SRLV free flocks (n=138) tested negative in the ELISA, while 50% of the samples from flocks with an unknown SRLV-status (n=111) were positive. For a subset of 59 bulk milk samples, agreement between ELISA results and leader-gag PCR results was almost 100%. These results demonstrate the potential of bulk milk testing as a cost effective tool for early detection of infection in dairy flocks, which is essential for SRLV-monitoring programs.

Veterinary RecordVolume 156, Issue 11 p. 350-351 Short Communication Lack of reversion in triclabendazoleresistant Fasciola hepatica F. H. M. Borgsteede PhD, F. H. M. Borgsteede PhD Animal Sciences Group WUR, Division of Infectious Diseases, PO Box 65, NL-8200 AB Lelystad, The NetherlandsSearch for more papers by this authorL. Moll, L. Moll Animal Health Service, PO Box 9, NL-7400 AA Deventer, The NetherlandsSearch for more papers by this authorP. Vellema DVM, PhD, P. Vellema DVM, PhD Animal Health Service, PO Box 9, NL-7400 AA Deventer, The NetherlandsSearch for more papers by this authorC. P. H. Gaasenbeek,, C. P. H. Gaasenbeek, Animal Sciences Group WUR, Division of Infectious Diseases, PO Box 65, NL-8200 AB Lelystad, The NetherlandsSearch for more papers by this author F. H. M. Borgsteede PhD, F. H. M. Borgsteede PhD Animal Sciences Group WUR, Division of Infectious Diseases, PO Box 65, NL-8200 AB Lelystad, The NetherlandsSearch for more papers by this authorL. Moll, L. Moll Animal Health Service, PO Box 9, NL-7400 AA Deventer, The NetherlandsSearch for more papers by this authorP. Vellema DVM, PhD, P. Vellema DVM, PhD Animal Health Service, PO Box 9, NL-7400 AA Deventer, The NetherlandsSearch for more papers by this authorC. P. H. Gaasenbeek,, C. P. H. Gaasenbeek, Animal Sciences Group WUR, Division of Infectious Diseases, PO Box 65, NL-8200 AB Lelystad, The NetherlandsSearch for more papers by this author First published: 12 March 2005 https://doi.org/10.1136/vr.156.11.350Citations: 32AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat No abstract is available for this article.Citing Literature Volume156, Issue11March 2005Pages 350-351 RelatedInformation

This paper describes an application of the second generation Sepia architecture implementation (Sepia-2) to support interactive visualization of scalar fields represented as very large 3D rectilinear grids. By employing pipelined sort-last associative blending operators a demonstration system yields scalable interactivity at 30 frames per second. We believe these results can be extended to support other types of structured and unstructured grids and a variety of GL rendering techniques. We show how to extend our single-stage demonstration system to larger multi-stage networks. This requires solving a dynamic mapping problem for blending operators that are similar to Porter-Duff compositing operators. We conclude by discussing technical and fundamental issues to address in future work.