Walburga Lutz

Characterization of pseudorabies virus of wild boar origin from Europe

Pseudorabies virus (PrV) infections appear to be more widely distributed in the European wild boar (Sus scrofa) population than assumed. In Europe, attempts to isolate and characterize the causative agents have been limited so far. We therefore collected and examined a total of 35 PrV isolates obtained from wild boar or hunting dogs in Germany, France, Spain, Italy, Slovakia and Hungary between 1993 and 2008. Restriction enzyme analysis of genomic DNA using BamHI showed that all isolates, except one, belonged to genogroup I but different subtypes were evident. For further investigations of the phylogenetic relationships, a 732-bp fragment of the glycoprotein C (gC) gene was amplified by PCR. Sequence analysis revealed about 40 variant positions within this fragment. Comparison of the nucleotide sequences supported the separation into a clade containing isolates from North-Rhine Westphalia, Rhineland-Palatinate (Germany), France and Spain (clade B) and an apparently more variable clade comprising isolates from Brandenburg, Baden-Wurttemberg, Saxony, Saxony-Anhalt (Germany), Slovakia, Hungary, Italy and France (clade A).

Do Canada geese (Branta canadensis Linnaeus, 1758) carry infectious agents for birds and man?

Currently, large groups of Canada geese (Branta canadensis Linnaeus, 1758) aggregate in recreational areas of north-western Germany. Questions have arisen as to whether these birds represent a special risk factor as a source of zoonotic agents for humans and as a source of viruses, causing notifiable or reportable diseases, for domestic poultry and waterfowl. To answer these questions, a total of 289 eggs were collected in 2002 and 2003 on a recreation site and assayed. Chlamydia psittaci was not isolated and neither was chlamydial antigen detected by polymerase chain reaction. All virus-isolation attempts were unsuccessful. Neither Salmonella spp. nor Campylobacter spp. was isolated from embryonic tissues, chorioallantoic membranes or yolk-sac membranes. The presence of antibodies against Newcastle disease virus and influenza A virus (haemagglutinin subtypes H5 and H7) was demonstrated in egg yolk. Antibodies were also detected against the egg-drop syndrome 1976 and duck plague viruses. It is concluded that further surveillance studies are needed for a reliable risk assessment.

Tracing the genetic roots of the sika deer Cervus nippon naturalized in Germany and Austria

To determine the geographical origin of the sika deer (Cervus nippon) naturalized in Germany and Austria, we sequenced the mitochondrial control region for 214 individuals. Adding these sequences to previously published data from native sika deer across its natural geographic range, the total comes to 245, extending what is already known about the geographical variation in this sequence in Cervus nippon. From these sequences, a neighbour-joining tree was constructed. This tree showed that the 49 different mitochondrial (mt)DNA types are grouped into three distinct phylogenetic clusters, which correspond to different geographic areas. Similarities between sequences of the naturalized sika deer and those described from native sika deer from both southern Honshu, Kyushu with associated islands, and northern Honshu suggest that the ancestors of the sika deer populations in Germany and Austria originated from the Japanese archipelago. In contrast, there is no evidence that female sika deer of Chinese, Taiwanese or north Vietnamese origin were involved in the ancestry of the present sika population in Germany and Austria.

A broad spectrum screening of Schmallenberg virus antibodies in wildlife animals in Germany

To identify native wildlife species possibly susceptible to infection with Schmallenberg virus (SBV), a midge-transmitted orthobunyavirus that predominantly infects domestic ruminants, samples from various free-living ruminants, but also carnivores, small mammals and wild boar were analyzed serologically. Before 2011, no SBV-specific antibodies were detectable in any of the tested species, thereafter, a large proportion of the ruminant population became seropositive, while every sample taken from carnivores or small mammals tested negative. Surprisingly, SBV-specific-antibodies were also present in a large number of blood samples from wild boar during the 2011/2012 and 2012/2013 hunting seasons. Hence, free-ranging artiodactyls may play a role as wildlife host.

Population genetic structure and the effect of founder events on the genetic variability of introduced sika deer, Cervus nippon, in Germany and Austria

The relationships among 214 wild-living sika deer from five locations in Germany and two in Lower Austria were examined using mitochondrial DNA (mtDNA) control region sequence. A total of 18 haplotypes are grouped consistently into two major divergent clades, A and B, which differ by a mean of 8.4% sequence divergence. Recently introduced sika deer showed a complex pattern of population structuring, which probably results from historical vicariance in at least two unknown source populations from southeastern Asia (as previously described by morphological and mtDNA findings), and subsequent population admixture as a result of human-mediated restocking. A strong genetic differentiation among populations was indicated by a global ΦST value of 0.78 reflecting mainly the differential distribution of clades A and B haplotypes. There was no association between related haplotypes and their distribution among local populations. These indicate that genealogy is a better predictor of the genetic affinity among most sika deer populations than their present-day locations. The abundant mitochondrial divergence we observed, may reflect a subspecies differentiation and could be associated with phenotypic differences among the introduced sika deer.

Absence of Antibodies to Foot-and-Mouth Disease Virus in Free-ranging Roe Deer from Selected Areas of Germany (2001-2002)

Blood samples (n =223) of free-ranging roe deer (Capreolus capreolus) were collected from selected hunting grounds in Germany between October 2001 and October 2002. Samples originated from Lower Saxony (n =43) and North-Rhine Westphalia (n =108) within a 20-km area (“cordon”) cordoned off along the border of The Netherlands. This is adjacent to the area of a foot-and-mouth disease outbreak that occurred between 21 March and 22 April 2001 in The Netherlands. Negative control samples were taken from northern Germany (Schleswig-Holstein, n =72). Two different enzyme-linked immunosorbent assays (ELISAs) were used for the detection of antibodies against foot-and-mouth disease virus (FMDV) serotype O strain Manisa. To confirm ELISA-positive results, a virus neutralization test was performed. All samples tested negative for antibodies against FMDV. These results suggest that FMDV was not transmitted to free-ranging roe deer living in parts of Germany adjacent to the area affected by the 2001 foot-and-mouth disease outbreak in The Netherlands.

Limited hybridization between domestic sheep and the European mouflon in Western Germany

European mouflons (Ovis orientalis musimon) are Mediterranean sheep that were introduced worldwide as park and game animals during the last few centuries. Today, European mouflons are endangered in their natural refuge areas. Mouflons are able to interbreed with domestic breeds to form fertile hybrids of an intermediate phenotype. As some introduced mouflon populations were deliberately crossed with primitive domestic breeds to improve their hardiness and trophy size and as evidence of uncontrolled interbreeding exists, the alleged purity of most mouflon populations has been debated for decades. In this study, we developed a genetic test to separate pure bred mouflons and domestic sheep from their hybrids. We searched for hybridization using insertionally polymorphic endogenous retroviruses and a set of novel microsatellites. Three instances were found of domestic sheep alleles in a retrotype dataset out of 192 mouflons from Western Germany. Considering the combined outcome of microsatellite and retrotype profiling, the amount of hybridization is negligible. We assume that the selective hunting of animals that show signs of hybridization in their phenotype is responsible for the low number of hybrids.

Schmallenberg virus in Germany 2011–2014: searching for the vectors

Following the emergence of Schmallenberg virus (SBV) in 2011, 21,397 culicoid biting midges (Diptera: Ceratopogonidae) from targeted and non-targeted sampling activities carried out during the summer months of 2011 to 2013 and in late 2014 in various regions in Germany were analyzed for the virus by real-time RT-PCR. While no SBV was found in biting midges collected during 2011 and 2013, 2 out of 334 pools including 20 and 22 non-engorged females of the Obsoletus complex sampled in 2012 tested positive for the SBV S-segment with Ct values of 42.46 and 35.45. In addition, 673 black flies (Diptera: Simuliidae) captured during the same studies were screened for the presence of SBV and proved negative. In late autumn 2014, biting midges were collected again in a limited study in eastern Germany after some cases of SBV infection had occurred in a quarantine station for cattle. Due to the unfavorable seasonal weather conditions, only few specimens were caught, and these were also negative for SBV. The German experience suggests that biting midge collections launched only after an outbreak and are not locally targeted may be ineffective as to virus detection. It rather might be advisable to collect biting midges at sentinel farms on a permanent basis so to have material available to be examined in the case of a disease outbreak.

Teilergebnisse der Nahrungsanalysen am Waschbären (Procyon lotor [L.]) in Nordhessen

ZusammenfassungVon 1976 bis 1979 wurden 150 Magen-Darm-Trakte und 250 Losungen des Waschbären (Procyon lotor [L.]) aus Nordhessen und angrenzenden Teilen von Nordrhein-Westfalen auf ihren Nahrungsinhalt untersucht. Annähernd jeweils ein Drittel der Nahrungsanteile entfallen auf Wirbeltiere, Wirbellose und Pflanzen. Jahreszeitlich bedingte Schwankungen der Beuteanteile sind naclizuweisen.SummaryFrom 1976 to 1979, 150 stomach/intestinal tracts and 250 faeces of raccoon (Procyon lotor [L.]) from North-Hessen and adjoining areas of North-Rhine Westphalia were examined on the basis of their food content. In each case, approximately one third of the food components were vertebrates, invertebrates and plants. Seasonal differences in the prey material can be detected.RésuméDe 1976 à 1979, le contenu alimentaire de 150 tractus digestifs et de 250 échantillons de matière fécale de ratons laveurs (Procyon lotor [L.]) récoltés dans le Nord de la Hesse et dans les régions limitrophes de Rhénanie-Westphalie a été analysé. Les Vértébrés, les Invertébrés et les végétaux se partagent chaque fois approximativement le tiers du contenu stomacal. Des variations saisonnières des quantités de proies sont décelables.

Dental Defects as a Potential Indicator of Chronic Malnutrition in a Population of Fallow Deer (Dama dama) from Northwestern Germany

We studied enamel defects in mandibular cheek teeth of fallow deer from an enclosed population that had grown far beyond the carrying capacity of its habitat. Macroscopic inspection revealed a high frequency of pathological enamel alterations in the permanent premolars and the third molar, which form late during dental development, while earlier forming teeth (deciduous premolars and first molar) were generally not affected. Macroscopic enamel alterations comprised opacity and posteruptive discoloration, loss of occlusal enamel ridges, and presence of enamel surface lesions. Backscattered electron imaging in the SEM revealed a marked hypomineralization and related increased porosity of the outer compared to the central and inner enamel portions in the affected teeth. In contrast, the enamel of the unaffected first molars showed a homogeneous high degree of mineralization. Microindentation hardness testing demonstrated a significantly reduced and highly variable hardness of the outer enamel of the affected teeth. The recorded enamel alterations are indicative of a disturbance of enamel maturation. Based on findings of experimental studies by other authors that explored the effects of dietary deficiencies on the mineralization of dental hard tissues in different mammal species, we suggest a dietary calcium deficiency as the cause of the observed pathological enamel changes in the fallow deer. The supposed calcium deficiency only affected teeth whose crown mineralization takes place after weaning, while the deciduous premolars and the first molar, whose crown formation occurs prenatally or during the early postnatal period of intense milk feeding, were unaffected. Anat Rec, 299:1409–1423, 2016.