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Outbreak of subclinical mastitis due to beta hemolytic group L streptococci (S. dysgalactiae ssp. equisimilis) in an Austrian dairy herd

This study is reporting an outbreak of subclinical mastitis due to beta-hemolytic group L streptococci in an Austrian dairy herd with a history of high somatic cell count. At the first survey 16 of 33 lactating cows (28 quarters of 132) were cultured positive for beta-hemolytic, CAMP and esculin negative cocci that grew on Columbia blood agar with small grey catalase negative colonies. With the commercial API 20 Strep system (bioMerieux, F) isolates were classified as members of streptococci group L. All tested strains (eight of 28) produced acid from ribose, lactose, trehalose, amidon and glycogen; they hydrolysed hippurate and showed beta-glucuronidase, beta-galactosidase, alkaline phosphatase, leucinaminopeptidase and arginindehydrolase activity. Isolates were sensitive to bacitracin but resistant to tetracycline. Using phenotypic characterisation as well as sequence analysis of the 16S-23S intergenic spacer region of a representative strain, recovered isolates were identified as Streptococcus (S.) dysgalactiae ssp. equisimilis. Mastitis was characterized by normal milk secretions and absence of clinical abnormalities but high elevations of somatic cell count. Based on the characteristics of the strains and on the observations during the first herd survey, contagious transmission during milking as a result of poor milking hygiene was assumed. The mastitis was controlled through implementation of a strict hygiene protocol including use of single-use udder towels, post milking teat desinfection and cluster disinfection between milking cows in combination with antibiotic treatment of infected udders.     

Field and laboratory investigations of Lumbricus badensis ecology and behaviour

正Dear Editor,Deep burrowing and soil surface feeding earthworms,so-called strict-anecic and epi-anecic species (Hoeffner et al., 2019), are a highly influential soil faunal group in many natural and manmade environments. Typically, they are relatively large and contribute substantially to the formation and processes of mull-type soils through effective foraging and incorporation of plant litter (Edwards and Bohlen,     

Climate change impacts on stand structure and competitive interactions in a southern Swedish spruce–beech forest

It is believed that European beech (Fagus sylvatica L.) will increase its competitive ability at its northern range margin in Scandinavia due to climate change. In mixed old-growth forests of beech and Norway spruce (Picea abies (L.) Karst.) at Siggaboda nature reserve (southern Sweden), stand structure characteristics were sequentially recorded in the years 2004, 2005 and 2007 as well as growth in stem diameter using tree-coring analyses. Using these measurements, we studied the effects on stand dynamics of an extreme storm event (2005 “Gudrun” hurricane), drought and heat (mid-summer 2006, spring 2007) and subsequent bark beetle attacks on spruce (growing season 2007), overlaid with warming tendencies. The storm, which caused disastrous damage in many stands nearby, had comparatively little impact on the structure of the spruce–beech stand. All together, only 32 trees (19 spruces, 10 beeches, 3 other species) per hectare were thrown or broken mainly in the leeward direction (NE) or impacted by secondary damage by uprooted neighbour trees; this represents 7% of the total tree number and 11% of the growing stock. Diameter and height structure did not change significantly. However, the 2006 drought and the 2007 attack of biotic agents changed the stand structure and composition strongly due to the death of about 19% of the dominating older spruce trees that accounted for 35% of total stand volume. This resulted in a considerable increase in beech’s contribution to stem number (4% increase) and wood volume of the living stand (7% increase). A comparison of diameter growth of beech and spruce during the periods 1894–1949 and 1950–2005 showed a distinct decrease in growth superiority of spruce during the last 50 years. These results support the idea of a northward migration of European beech as a nemoral tree species in Sweden, due to a higher tolerance to the abiotic and biotic threats accompanying climate change and an increased competitive ability compared to boreal tree species Norway spruce.     

Multivariate genetic analysis of canine hip and elbow dysplasia as well as humeral osteochondrosis in the Bernese mountain dog

In the present study genetic parameters for canine hip dysplasia (CHD), canine elbow dysplasia (CED) and osteochondrosis dissecans of the humeral head (OCD) were analysed in Bernese mountain dogs. The data set included the official scores for CHD and CED from 5534 Bernese mountain dogs born in the years 1995-2008. A multivariate linear animal model was employed to estimate heritabilities, additive genetic and residual correlations using residual maximum likelihood (REML). Heritability estimates were h2 = 0.26 for CHD, h2 = 0.22 for CED and h2 = 0.40 for OCD. The additive genetic correlation between CHD and CED was 0.31, between CHD and OCD 0.25, and between CED und OCD -0.49. A further multivariate analysis of the prevalence of the FCP (fragmented coronoid processus), CHD and OCD revealed a heritability of h2 = 0.59 for FCP. The additive genetic correlations among FCP and CHD as well CED except FCP were positive, but negative with OCD. Multivariately estimated breeding values will lead to higher genetic progress because the correlation structure of the traits can be taken into account and possible genetic antagonisms among traits are better reflected in the breeding values.     

Molecular subtype-specific clinical diagnosis of prion diseases

Sporadic Creutzfeldt-Jakob disease (sCJD) is a rare transmissible disease caused by accumulation of pathological prion protein (PrP(sc)) in the CNS. According to the codon 129 polymorphism (methionine or valine) and the prion protein type 1 or 2, a classification into distinct subtypes was established. Further analysis of these subtypes detected atypical clinical forms with longer disease duration or younger age at onset. The CJD subtype influences sensitivity of the technical investigations such as 14-3-3 in CSF, periodic sharp wave complexes in the EEG or hyperintense basal ganglia in MRI. A further characterization of these subtypes is important for reliable diagnosis and identification of rare disease variants. The aim is to establish specific patterns of test results and clinical findings. These improvements in diagnostics may be the reason for the apparent increase in sCJD incidence in Germany from 0.9 in 1994 to 1.6 in a million in 2005. Despite careful surveillance, no patient with variant CJD has been detected to date in Germany. Here we present the data of the CJD surveillance of the last 13 years. Additionally, the improvements in diagnostics and differential diagnosis are discussed.     

Molybdenum fractions and mobilization kinetics in acid forest soils

We extracted molybdenum (Mo) from eight acid forest soils (19 A, E, and B horizons) in NE-Bavaria and from one site in the Ore Mountains, using (1) anion exchange-resin, (2) 0.2 M ammonium oxalate, and (3) ascorbic acid/ammonium oxalate. The Mo concentrations in the anion exchange-resin fraction varied between 5 and 28 μg kg^-1. Oxalate-extractable Mo ranged from 44 to 407 μg kg^-1 and after reduction of iron (Fe) with ascorbic acid, 135 to 1071 μg Mo kg^-1 were extracted. The lowest concentrations of Mo were measured in acid and sesquioxide impoverished E horizons. The total concentrations of Mo in spruce needles correlated with ion exchange resin extractable Mo, indicating that this fraction represents Mo readily available to plants. The Mo and Fe dissolution kinetics during oxalate extraction were studied on 8 of the soil samples to obtain further information on Mo mobilization. Oxalate extractable iron (Fe_o) was mobilized within a few hours. A first order equation was applicable to the Fe dissolution kinetics with the rate constants ranging between 0.9 and 9.0 h^-1. The mobilization of Mo occurred in two distinct stages. An initially rapid dissolution was followed by a further increase in extractable Mo but with slower kinetics. A combined first order-diffusion equation was found to be appropriate for modelling the results. The first order rate constants for Mo mobilization ranged from 0.6 to 11.4 h^-1. However, correlations between the rates of reaction of Mo and Fe could not be established, indicating that Mo is either not distributed equally along Fe minerals or that there is another pool, possibly the organic substance of the soil, from which Mo is extractable by oxalate.     

Experience versus expectation: farmers’ perceptions of smart farming technologies for cropping systems across Europe

Precision Agriculture - Technological innovations are changing mechanisation in agriculture. The most recent wave of innovations referred to as smart farming technologies (SFT), promise to improve...     

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Earthworms promote the reduction of Fusarium biomass and deoxynivalenol content in wheat straw under field conditions

A field experiment was conducted to elucidate ecosystem services provided by earthworms on the repression of phytopathogenic and toxinogenic fungi. The study focussed on decomposing Fusarium culmorum-infected and deoxynivalenol (DON)-contaminated wheat straw remaining on the soil surface as part in conservation tillage. Mesocosms were established in the topsoil of a winter wheat field located in Northern Germany, where conservation tillage has been practised for 20 years. Besides a non-earthworm treatment, two earthworm species were inoculated in the mesocosms either separately or combined: Lumbricus terrestris (anecic, detritivorous) and Aporrectodea caliginosa (endogeic, geophagous). The earthworms were exposed either to artificially Fusarium-infected wheat straw highly contaminated with DON or to non-infected straw serving as a control. The experiment was conducted during an eight week period after harvest from mid August to mid October. For both species, the artificially Fusarium-infected and DON-contaminated wheat straw was a more attractive food source than the non-infected control. In contrast to A. caliginosa, L. terrestris incorporated infected straw faster into the soil compared to control straw. Furthermore, the reduction of Fusarium biomass and DON concentration in wheat straw was significantly higher in the presence of L. terrestris than in treatments with A. caliginosa and without earthworms. Here, no significant differences could be measured between the Fusarium biomass and DON concentration in wheat straw. A. caliginosa seems not to be relevant for the reduction of Fusarium biomass and DON concentration. We concluded that amongst earthworms, anecic detritivorous species are the drivers to compensate possible negative consequences (like crop infection) of conservation tillage. They take an important role in the control of phytopathogenic and toxinogenic fungi surviving on plant residues and in the degradation of their mycotoxins.