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Genetic analyses of highly pathogenic avian influenza A(H5N8) virus from the Netherlands, and comparison with strains from Europe, South Korea, and Japan, showed a close relation. Data suggest the strains were probably carried to the Netherlands by migratory wild birds from Asia, possibly through overlapping flyways and common breeding sites in Siberia.

At the end of 2011, a new Orthobunyavirus was discovered in Germany and named Schmallenberg virus (SBV). In the Netherlands malformations in new-born ruminants were made notifiable from the 20th of December 2011. After a notification, malformed new-borns were necropsied and brain tissue was sampled for reverse transcription-polymerase chain reaction (RT-PCR). In addition, blood samples from mothers of affected new-borns were tested for antibodies in a virus neutralization test (VNT). The aim of this study was to summarize and evaluate the diagnostic data obtained and to gain insight into the possible regional differences. In total 2166 brains were tested: 800 from lambs, 1301 from calves and 65 from goat kids. Furthermore 1394 blood samples were tested: 458 from ewes, 899 from cows and 37 from goats. Results showed that 29% of the lamb brains, 14% of the calf brains, and 9% of the goat kid brains were RT-PCR positive. The number of malformed and RT-PCR positive lambs decreased over time while the number of malformed and RT-PCR positive calves increased. In the VNT 92% of the ewes, 96% of the cows and 43% of the goats tested positive. Combining RT-PCR and VNT results, 18% of all farms tested positive in both the RT-PCR and VNT. The relative sensitivity and specificity of the RT-PCR are 19% and 97% respectively, and of the VNT 99% and 6%. The results show a widespread exposure to SBV and the regional evaluation seems to indicate an introduction of SBV in the central/eastern part., (Copyright © 2013 Elsevier B.V. All rights reserved.)

The emergence of Schmallenberg virus (SBV), a novel orthobunyavirus, in ruminants in Europe triggered a joint veterinary and public health response to address the possible consequences to human health. Use of a risk profiling algorithm enabled the conclusion that the risk for zoonotic transmission of SBV could not be excluded completely. Self-reported health problems were monitored, and a serologic study was initiated among persons living and/or working on SBV-affected farms. In the study set-up, we addressed the vector and direct transmission routes for putative zoonotic transfer. In total, 69 sheep farms, 4 goat farms, and 50 cattle farms were included. No evidence for SBV-neutralizing antibodies was found in serum of 301 participants. The lack of evidence for zoonotic transmission from either syndromic illness monitoring or serologic testing of presumably highly exposed persons suggests that the public health risk for SBV, given the current situation, is absent or extremely low.

Infections with Schmallenberg virus (SBV) are associated with congenital malformations in ruminants. Because reporting of suspected cases only could underestimate the true rate of infection, we conducted a seroprevalence study in the Netherlands to detect past exposure to SBV among dairy cattle. A total of 1,123 serum samples collected from cattle during November 2011-January 2012 were tested for antibodies against SBV by using a virus neutralization test; seroprevalence was 72.5%. Seroprevalence was significantly higher in the central-eastern part of the Netherlands than in the northern and southern regions (p<0.001). In addition, high (70%-100%) within-herd seroprevalence was observed in 2 SBV-infected dairy herds and 2 SBV-infected sheep herds. No significant differences were found in age-specific prevalence of antibodies against SBV, which is an indication that SBV is newly arrived in the country.

A randomized, controlled field trial with dairy cows demonstrated an adverse effect of vitamin E supplementation during the dry period on mastitis incidence in early lactation. This study was conducted on farms with historically high rates of mastitis to investigate the benefit of vitamin E supplementation on udder health; however, the outcome showed an adverse effect. The aim of the study was to evaluate whether daily supplementation of 3,000 IU of vitamin E to dairy cows during the dry period could improve udder health in commercial herds with a high incidence of mastitis. On 5 dairy farms, dry cows were randomly divided into 2 experimental groups: a high and a low group. Both groups received a dry cow mineral mix providing 3,000 or 135 IU of vitamin E/cow per day, respectively, between dry-off and calving for a mean period of 8 wk. Providing 3,000 IU of vitamin E exceeds NRC standards, but this amount has been used in previous studies. The experiment, as well as the majority of the statistical analysis, were carried out blinded. Blood was sampled 3 times before calving and on calving day. Serum was analyzed for vitamin E and cholesterol. Vitamin E and the vitamin E:cholesterol ratio were analyzed as dependent variables in mixed models and Student's t-tests to study trends in time and differences between groups. Relative risk calculation and survival analysis were used to study the effect of supplementation on mastitis incidence in the first 3 mo of lactation. The results showed that vitamin E supplements increased both absolute vitamin E and the ratio of vitamin E to cholesterol in blood. In the high group, significantly more subclinical and clinical cases occurred, showing the same trend on all farms. In this study, an initial vitamin E level at dry off above 14.5 μmol/L was a risk factor for clinical mastitis, suggesting that the vitamin E status at the start of the dry period is important. It is recommended to work out exactly at what threshold vitamin E is harmful for udder health before new trials with high dosages of vitamin E are started. Additionally, further research is required to investigate the mechanism by which vitamin E affects udder health., (Copyright © 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

The aim of this study was to evaluate, retrospectively, which physiological states influenced the effect of vitamin E supplements during the dry period on the level of oxidative stress at 2 wk antepartum. Furthermore the effect of oxidative stress at 2 wk antepartum on the risk of clinical mastitis in early lactation was investigated. Cows experience oxidative stress around calving. Vitamin E is able to decrease oxidative stress by scavenging free radicals. Normally, vitamin E radicals formed when vitamin E reacts with free radicals are regenerated by a network of other antioxidants, termed the "vitamin E regeneration system" (VERS). In case of vitamin E supplementation, VERS should be sufficient to regenerate formed vitamin E radicals; if not, oxidative stress might increase instead of decrease. Additionally, the level of oxidative stress and vitamin E might be important physiological states to evaluate before supplementation. In a clinical trial, 296 cows on 5 farms were randomly divided into 2 groups, supplemented with a mineral mix between dry off and calving that supplied 3,000 or 135 IU/d, respectively. Blood samples collected at dry off and 2 wk antepartum were analyzed for vitamin E, reactive oxygen metabolites, ferric-reducing ability of plasma, glutathione peroxidase, and malondialdehyde. Cows were allocated retrospectively into 8 subgroups based on the level of oxidative stress, vitamin E, and VERS status at dry off. To evaluate whether differences in physiological states at dry off influenced the effect of vitamin E supplementation on the level of oxidative stress, group effects (supplemented vs. control) were studied with Student's t-test for all 8 subgroup at 2 wk antepartum. Differences in physiological states at dry off influenced the effect of vitamin E supplements. In 2 insufficient VERS subgroups, the supplemented group had higher levels of free radicals at 2 wk antepartum compared with the control group. Relative risk calculation was used to study the effect of oxidative stress at 2 wk antepartum on the incidence of mastitis in the first 100 d of lactation. Higher levels of oxidative stress at 2 wk antepartum were related to higher risk of clinical mastitis. In conclusion, not every dry cow responded well to high vitamin E supplementation. This subgroup analysis provides a possible explanation for the unexpected adverse effects observed in the clinical trial., (Copyright © 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

The effect of oral vitamin E supplementation during the dry period on serum biomarkers of oxidative status was evaluated in an observational field study. Ninety-eight cows were selected from 26 herds in the Netherlands. On 15 farms dry cows were supplemented with a dry-cow mineral mix containing 1000 IU vitamin E (vitamin E+ group, n = 52), and on 11 other farms dry cows did not receive the supplement (control group, n = 48). A blood sample was taken from all cows between 0 and 28 days before calving. Serum levels of alpha-tocopherol, cholesterol, triacylglycerol, superoxide dismutase (SOD), glutathione peroxidase (GSHpx), uric acid, albumin, protein sulphydryl oxidation level, reactive oxygen metabolites (ROM), iron, the ferric reducing ability (FRAP), and malondialdehyde (MDA) were measured. Alpha-tocopherol levels were significantly higher in the vitamin E+ group, as was the alpha-tocopherol:cholesterol ratio. MDA levels were significantly lower in the vitamin E+ group, suggesting that levels of lipid peroxidation were lower with vitamin E supplementation. In conclusion, vitamin E supplementation increases alpha-tocopherol and lowers MDA serum levels.

Within a week of being turned out to pasture, 3 of 30 heifers displayed a symptom described in the literature as "Flying Scapulas". The cause of this symptom is severe muscular dystrophy, with subsequent rupture of the ventral serrate muscles. Blood analysis revealed a deficiency of both vitamin E and selenium in all three heifers. No new clinical cases of muscular dystrophy were observed after the animals were housed and given vitamin E and selenium supplements. As far as is known, this is the first report in which a deficiency of both vitamin E and selenium was found in animals with the clinical symptoms of Flying Scapulas. This is the first description of Flying Scapulas in cattle in The Netherlands.