RADIOGRAPHIC IMAGING OF OTITIS MEDIA AND INTERNA IN PIGS

Middle and inner ear infections have been reported as a clinical entity in swine, other animal species and humans. In pigs, the anatomical-pathological and microbiological findings have been described. In this report, we describe radiographic findings in affected pigs. A total of 25 pigs with a head tilt and circling, as clinical signs of otitis media and interna, were examined. The majority were weaner-pigs with dyspnea or rhinitis. In radiographs, there was an increased opacity of the bulla tympanica, often accompanied by marginal destruction or thickening of the bulla wall. The radiographic findings confirmed the clinical diagnosis in each affected pig, but there were 5 false positive interpretations.     

Health screening of free-ranging European brown hares (Lepus europaeus) on the German North-Sea island Pellworm

Background

A sudden decline of the European brown hare (Lepus europaeus) population in one of the best hunting districts for small game species in northern Germany, the German North-Sea island Pellworm, in the years 2007/08 following marked habitat changes led to the implementation of a thorough health assessment program of the population. 110 animals were collected during the normal hunting season in the years 2010 and 2011. A post-mortem examination and histopathological investigation was performed on all animals. Additionally, routine bacteriology of the small intestine and parasitology were carried out. Sera of hares were tested for European Brown Hare Syndrome (EBHS) by enzyme linked immunosorbent assay, and for Treponema sp. by indirect immunofluorescent test. Additional testing was performed when deemed necessary.

Results

The most striking result was a shift in the intestinal bacterial flora towards Gram-negative Enterobacteriaceae with a predominance of either Escherichia coli, or Aeromonas sp., or a high-grade double-infection with these two pathogens with subsequent catarrhal enteritis. Additionally, a marked coccidiosis, and varying infestations with the nematode Trichostrongylus retortaeformis were found. The sero-prevalence for EBHS was 78.1%, and for Treponema 43.9%.

Conclusions

The shift and decrease in diversity of the intestinal flora was the main and most consistent result found. In the authors’ opinion the change of the habitat combined with other stressors increased the animals’ sensitivity to ubiquitous bacterial species and parasites which usually would not have such fatal effects.     

Effects of the nitrification inhibitor nitrapyrin and the plant growth regulator gibberellic acid on yield-scale nitrous oxide emission in maize fields under hot climatic conditions

Nitrification inhibitors are widely used in agriculture to mitigate nitrous oxide(N₂O)emission and increase crop yield.However,no concrete information on their mitigation of N₂O emission is available under soil and environmental conditions as in Pakistan.A field experiment was established using a silt clay loam soil from Peshawar,Pakistan,to study the effect of urea applied in combination with a nitrification inhibitor,nitrapyrin(2-chloro-6-tri-chloromethyl pyridine),and/or a plant growth regulator,gibberellic acid(GA_3),on N₂O emission and the nitrogen(N)uptake efficiency of maize.The experimental design was a randomized complete block with five treatments in four replicates:control with no N(CK),urea(200 kg N ha^-1)alone,urea in combination with nitrapyrin(700 g ha^-1),urea in combination with GA_3(60 g ha^-1),and urea in combination with nitrapyrin and GA_3.The N₂O emission,yield,N response efficiency,and total N uptake were measured during the experimental period.The treatment with urea and nitrapyrin reduced total N₂O emission by 39%–43%and decreased yield-scaled N₂O emission by 47%–52%,relative to the treatment with urea alone.The maize plant biomass,grain yield,and total N uptake increased significantly by 23%,17%,and 15%,respectively,in the treatment with urea and nitrapyrin,relative to the treatment with urea alone,which was possibly due to N saving,lower N loss,and increased N uptake in the form of ammonium;they were further enhanced in the treatment with urea,nitrapyrin,and GA_3 by 27%,36%,and 25%,respectively,probably because of the stimulating effect of GA_3 on plant growth and development and the reduction in biotic and abiotic stresses.These results suggest that applying urea in combination with nitrapyrin and GA_3 has the potential to mitigate N₂O emission,improve N response efficiency,and increase maize yield.     

Erosion processes and erodibility of cultivated soils in North Rhine‐Westphalia under artificial rain. II. Results of field experiments and comparison with laboratory trials

In the densely populated state of North Rhine‐Westphalia, soil erosion by water causes substantial on‐site degradation and off‐site damages. The implementation of soil‐conservation measures is improved, if soil erodibilities and erosion processes are known. In a state‐wide investigation, we aimed to representatively assess soil‐erosion processes and erodibilities of cultivated soils. For this purpose, we measured surface runoff and soil‐loss rates of 28 cultivated soils with field plots under artificial rain. In the field experiments, surface runoff and soil loss indicated high sealing susceptibilities and high erodibilities on soils of quite different textures including a clay silt, a loam silt, a loam sand, a sand loam, and two standard loams. Rill formation causing high soil‐loss rates was observed on a clay silt (soil BM) and on a loam silt (soil RB), the latter yielding an empirical K‐factor of 1.66 t ha^–1 h N^–1. K‐factors of other silty soils ranged from 0.04 to 0.48, whereas sandy soils and clayey soils had K‐factors ranging from 0.00 to 0.32, and 0.00 to 0.12, respectively. Comparatively high erodibilities of two silt clays were due to saturation overland flow. Erosion processes and erodibilities of soils with similar texture varied to a large extent, possibly caused in part by seasonal differences in the timing of erosion tests. Surface runoff was different in field experiments compared with laboratory experiments (companion paper) conducted with topsoil material taken from the field plots. In addition, higher concentrations of suspended sediment were recorded on average in the field than in the laboratory. These differences might reflect the influence of the subsoil and are due to higher transport capacities on longer plots in the field. Thus, laboratory experiments can complement but not replace costly field trials for K‐factor determination. Empirical K‐factors derived from field and laboratory experiments are in general lower than K‐factors of other soils in Germany or calculated K‐factors derived from pedotransfer functions, which might be attributed to a more maritime‐type climate in North Rhine‐Westphalia. Since the temporal variability of erodibility was not assessed, the reported K‐factors should be regarded as preliminary.     

Heterotrophic nitrification is the predominant NO3 − production pathway in acid coniferous forest soil in subtropical China

To date, occurrence and stimulation of different nitrification pathways in acidic soils remains unclear. Laboratory incubation experiments, using the acetylene inhibition and ¹⁵N tracing methods, were conducted to study the relative importance of heterotrophic and autotrophic nitrification in two acid soils (arable (AR) and coniferous forest) in subtropical China, and to verify the reliability of the ¹⁵N tracing model. The gross rate of autotrophic nitrification was 2.28 mg?kg^?1?day^?1, while that of the heterotrophic nitrification (0.01 mg?kg^?1?day^?1) was negligible in the AR soil. On the contrary, the gross rate of autotrophic nitrification was very low (0.05 mg?kg^?1?day^?1) and the heterotrophic nitrification (0.98 mg?kg^?1?day^?1) was the predominant NO₃ ^? production pathway accounting for more than 95 % of the total nitrification in the coniferous forest soil. Our results showed that the ¹⁵N tracing model was reliable when used to study soil N transformation in acid subtropical soils.     

Metabolomic responses in grain,ear, and straw of winter wheat under increasing sulfur treatment

Only little is known about the effect of a varying sulfur (S) nutrition on the pattern of metabolites in different organs of the ears of winter wheat (Tritcum aestivum L.) at final maturity. More insights into the metabolome as influenced by increasing S‐fertilizer rates would, however, be of particular interest in order to unravel S‐dependent physiological processes related to grain filling in wheat. We have therefore investigated the effects of varying sulfur nutrition on metabolite composition and distribution in the organs of the wheat ear and vegetative organs at final maturity. Gas chromatography–mass spectrometry–based metabolite profiles revealed that S deficiency decreased the bulk of metabolites in the straw in favor of an increasing metabolite concentration in the husk, rachis, and grains. Surprisingly, only four out of 109 detectable metabolites, namely N‐acetyl glucosamine, lysine, ferulic acid, and β‐aminoisobutyric acid were most responsible for organ‐specific differences in the metabolite profiles. Under S‐deficient conditions, N‐acetyl‐glucosamine, lysine, and β‐aminoisobutyric were increasingly transferred from source tissues into the ears and grains.     

Functional beetle diversity in managed grasslands: effects of region,landscape context and land use intensity

Current biodiversity conservation policies have so far had limited success because they are mainly targeted to the scale of individual fields with little concern on different responses of organism groups at larger spatial scales. We investigated the relative impacts of multi-scale factors, including local land use intensity, landscape context and region, on functional groups of beetles (Coleoptera). In 2008, beetles were suction-sampled from 95 managed grasslands in three regions, ranging from Southern to Northern Germany. The results showed that region was the most important factor affecting the abundance of herbivores and the abundance and species composition of predators and decomposers. Herbivores were not affected by landscape context and land use intensity. The species composition of the predator communities changed with land use intensity, but only in interaction with landscape context. Interestingly, decomposer abundance was negatively related to land use intensity in low-diversity landscapes, whereas in high-diversity landscapes the relation was positive, possibly due to enhanced spillover effects in complex landscapes. We conclude that (i) management at multiple scales, from local sites to landscapes and regions, is essential for managing biodiversity, (ii) beetle predators and decomposers are more affected than herbivores, supporting the hypothesis that higher trophic levels are more sensitive to environmental change, and (iii) sustaining biological control and decomposition services in managed grassland needs a diverse landscape, while effects of local land use intensity may depend on landscape context.     

Fusarium genetic traceability: Role for mycotoxin control in small grain cereals agro-food chains

Risks associated with mycotoxin contamination of cereals, that are included in the ten major staple foods and greatly contribute to the dietary energy intake, are of worldwide relevance. In small grain cereals, mycotoxins are produced by fungi such as Aspergillus, Penicillium, Alternaria and Fusarium that colonize the plant in the field and can grow during the post-harvest period, producing several classes of mycotoxins. The identification of mycotoxigenic fungal species and strains is essential for developing effective strategies for control. For this purpose, genetic traceability has proved to be a valuable tool that can be applied along the whole production chain, starting in the field for early diagnosis of FHB (Fusarium Head Blight) disease to the final processing steps, such as malting or pasta making. In this paper, DNA-based analytical tools that are currently available for the identification and quantification of mycotoxigenic fungal species and strains are reviewed, with particular emphasis on Fusarium, and their possible applications in mycotoxin control in small grain cereal chains are discussed.