A long-term serological survey on Aujeszky's disease virus infections in wild boar in East Germany.

Between 1985 and 2008, a total of 102,387 wild boar sera originating from Eastern Germany covering an area of 108 589 km2 were tested for the presence of Aujeszky's disease virus (ADV)-specific antibodies. From 1985 until 1991 and from 1992 until 2008, wild boar sera were exclusively investigated using either conventional seroneutralization assays (n=39 621) or commercial gB and full antigen ELISAs (n=62,766), respectively. Spatial-temporal analysis revealed an increasing ADV seroprevalence from 0·4% to 15·9%, on average, during the 24-year observation period that went along with a continuous spread of the infection in a western direction. During 2006 and 2008, 18% of the 66 affected districts had ADV seroprevalences >30%. There was a significant correlation between ADV seroprevalence and the hunting index of population density (HIPD) of wild boar in the entire study area, although this did not hold true for some regions. Seroprevalences did not differ between sexes but were age-dependent. East Germany has been officially free of Aujeszky's disease (pseudorabies) in domestic pigs since 1985. Although a risk for domestic pigs cannot be completely ruled out, experience has shown that ADV in domestic pigs could be eliminated although the virus was present in the wild boar population. Despite increasing ADV seroprevalence in the East German wild boar population no spillover infections from wild boar to domestic pigs have been reported. To further trace ADV infections in the wild boar population in Germany, a nationwide serological monitoring programme should be implemented.

Retrospective serological survey on selected viral pathogens in wild boar populations in Germany.

The objective of this study was to retrospectively evaluate the occurrence of porcine parvovirus (PPV), Aujeszky's disease virus (ADV), transmissible gastroenteritis virus (TGEV), porcine respiratory coronavirus (PRCV), porcine reproductive and respiratory syndrome virus (PRRSV) and swine influenza virus (SIV) in selected wild boar populations in Germany (n = 1,221). Commercial enzyme linked immunosorbent assay and hemagglutination inhibition tests were used for serological monitoring. The serosurvey revealed seroprevalence rates of 64.28%, 11.26%, 7.87%, 7.84%, 3.82% and 1.59% for PPV, ADV, PRCV, SIV, PRRSV and TGEV, respectively. The seroprevalence rates differed between populations and age classes with the highest number of antibody-positive wild boars in older animals (>1 year old). No antibodies to TGEV were found in Baden-Wuerttemberg and in Mecklenburg-Western Pomerania (investigation period 1997/1998). In addition, sera collected in Mecklenburg-Western Pomerania in 1997/1998 were negative for SIV. Even though the seroprevalence rates established for these viruses, except for PPV, were relatively low, wild boars may act as a reservoir for pathogens and a source of infection for domestic pigs and humans. Based on the epidemiological situation, no risk of a spread of these viruses should emanate from wild boars, neither for wildlife nor for livestock. However, effective and science-based disease monitoring programmes should continuously be carried out in wild boar populations.

Diagnostic procedures after completion of oral immunisation against classical swine fever in wild boar.

The purpose of this paper is to define diagnostic procedures for wild boar after the completion of oral immunisation against classical swine fever (CSF). Epidemiological analysis of CSF in wild boar in Germany demonstrated that it is vital to carry out virological investigations on all animals found dead, sick or involved in traffic accidents. In principle, this should ensure an effective and prompt diagnosis of CSF. In addition, a defined number of wild boar, especially young animals < or = 6 months old, should also be tested for CSF virus to guarantee a high confidence level in the virological monitoring. Which animals should be examined serologically depends on the age class investigated, the season in which vaccination was stopped and the period of time since completion of vaccination. Therefore, different serological procedures have been defined for different situations during the first three years after completion of oral immunisation.

Epizootiological investigations of canine distemper virus in free-ranging carnivores from Germany.

Canine distemper virus (CDV) infects a broad range of carnivores. To assess whether wild carnivores may play a role in the epidemiology of CDV in domestic dogs in Germany, the seroprevalence of CDV was determined. In sera from red foxes (30 of 591 (5%)) and stone martens (2 of 10 (20%)) antiviral antibodies were detected using a neutralization assay, whereas sera of raccoons, two mink, one pine marten and one raccoon dog were negative. In foxes, there was a significantly higher prevalence in urban and suburban compared to rural regions. When testing lung and spleen tissue samples (fox, badger, stone marten, polecat, raccoon dog) 13 of 253 (5.1%) foxes, 2 of 13 (15.4%) stone martens and 2 of 6 (33%) badgers were virus positive using RT-PCR. Phylogenetic analysis based on partial sequences of the F gene revealed a distinct relatedness to canine CDV isolates. Together, the data support the concept of transmission of CDV between domestic dogs and wild carnivores.

Classical swine fever virus: clinical, virological, serological and hematological findings after infection of domestic pigs and wild boars with the field isolate "Spante" originating from wild boar.

A classical swine fever virus (CSFV) field isolate originating from wild boar was investigated on its virulence in domestic pigs and wild boar. Three weaner pigs and two wild boars (yearlings) were intranasally inoculated with the isolate "Spante" and tested for clinical, virological, hematological and serological findings until day 31 after infection (p. i.). One day p. i. the piglets were put in contact to three sentinel pigs. During a period of 31 d neither the domestic pigs nor the wild boars showed clinical signs specific for CSF. Two infected weaner pigs became transiently viraemic, transmitted CSFV in nasal secretions, showed a slight leukopenia and reacted serologically positive. The contact infection resulted in a viraemia in two sentinel piglets on day 30. Only one contact animal developed antibodies. None of the wild boars became viraemic, excreted CSFV in nasal secretions or developed antibodies. The CSFV isolate "Spante" represents a low virulent virus. Referring to a significant higher percentage of virologically positive tissue samples after nested PCR compared with the virus isolation, persistence of CSFV is discussed.

Antibodies against rabbit hemorrhagic disease virus in free-ranging red foxes from Germany.

Antibodies against rabbit hemorrhagic disease virus (RHDV) from 352 red fox (Vulpes vulpes) sera collected in Germany (Mecklenburg-Vorpommern) in 1993 were tested by a blocking enzyme-linked immunosorbent assay (ELISA) test kit. Ninety samples with positive or suspected results also were analyzed by the hemagglutination inhibition test (HIT). Eighteen serum samples (5%) were positive with the blocking ELISA and eight of these also were positive with HIT. The 18 positive sera also were tested by blocking ELISA for antibodies against European brown hare syndrome virus (EBHSV) and by sandwich ELISA to detect for antibodies against RHDV and EBHSV antigen. Antibodies were not found against EBHSV using the blocking ELISA. With the sandwich ELISA, six samples were positive against RHDV and also against EBHSV, indicating cross-reactivity between determinants of both viruses. However, antibody titers against RHDV were higher than against EBHSV in five samples, and in one animal titers were similar. In addition, two positive samples were investigated by Western blot immunoassay which showed clear positive reactions with the two main peptide bands of EBHSV and RHDV. Comparison of the areas below the peaks of the bands after immunoblotting indicated that there was a stronger reaction with the two main polypeptides of RHDV than with the two main peptides of EBHSV. This is the first report of calicivirus antibodies in free-ranging red foxes. Based on the specificity of the tests, the antibodies detected against caliciviruses may be induced by RHDV. There is a potential link for RHDV between free-ranging rabbits and foxes.

[Serologic investigations on the occurrence of Maedi-Visna antibodies in game ruminants]. / Serologische Untersuchungen zum Vorkommen von Maedi-Visna-Virusantikörpern bei Wildwiederkäuern.

The lentiviruses of small domestic ruminants (maedi-visna and caprine arthritis-encephalitis virus) have been shown to be infective for each other. There are only few investigations of virus susceptibility of other species of animals. The aim of our study reported here was to evaluate sera of wild animal species for lentivirus antibodies. 344 sera of Capreolus capreolus, Cervus elaphus and Dama dama from a territory with known sheep populations prevalence were tested in the agar gel immunodiffusion test using MVV-p28 and -gp 135 antigens. While about 27% of sheep herds have been shown to be MVV positive, no wild animal serum has been reacted with any of the antigens.

[Thiocyanate blood levels in roe deer, red deer, fallow deer and wild boar]. / Untersuchungen zum Thiocyanatserumspiegel bei Reh-, Rot-, Dam- und Schwarzwild.

The following serum levels of thiocyanate (SCN-) were found in game: roe 6.6 +/- 4 mg/l, red deer 5.5 +/- 3.2 mg/l, fallow-deer 5.1 +/- 2.8 mg/l, and wild boar 4.8 +/- 4.5 mg/l (variation 0.6-32.6 mg SCN-/l). These levels are distinctly higher than in domestic animals under stall-feeding with exception of mast calves which were fed milk-substitutes. The SCN- serum level of calves, sheep and horses reach at pasturing nearly the level of game. The higher SCN- serum level of cloven-hoof game resp. by pasturing of domestic animals is caused by higher alimentary SCN- intake.

[IBR/IPV virus antibodies in the wild boar--the host spectrum of herpesviruses]. / IBR/IPV-Virusantikörper beim Schwarzwild--Beitrag zum Wirtsspektrum der Herpesviren.

Studies with serum neutralization test on 443 sera from black boar against antibodies of BHV 1 have produced the first evidence ever to the presence in this species. Titres were about 1:2. Findings are discussed under aspects of spectrum of BHV 1 with reference to swine and under epizootiological aspects.

[Seroepidemiologic studies of the distribution of respiratory syncytial virus in wild ruminants]. / Seroepidemiologische Untersuchungen zur Verbreitung von Respiratory Syncytial Virus unter Wildwiederkäuern.

Sera from wild ruminants (302 roe, 39 red deer, 17 fallow deer, 1 mouflon) were tested for antibodies against respiratory syncytial virus (RSV). 22 sera (6.1%) were positive: 20 roe, 1 red deer, 1 mouflon. The findings are discussed from the epizootiological point of view.

[Detection of antibodies against Brucella in the aqueous humor using ELISA]. / Nachweis von Antikörpern gegen Brucellen im Augenkammerwasser mittels ELISA.

In aqueous bulbi of experimentally against Brucella abortus immunized guinea pigs and rabbits specific antibodies could be detected by ELISA-tests. This first demonstration of brucella antibodies in the aqueous shows that aqueous can be used for serological examinations. For practical use more investigations in experimental animals are necessary, e.g. on kinetics of orbital antibodies absence of interfering factors and biomechanics of proteins in aqueous.

Fengabine, a novel antidepressant GABAergic agent. II. Effect on cerebral noradrenergic, serotonergic and GABAergic transmission in the rat.

The effects of fengabine (a novel benzylidene derivative possessing clinically demonstrated antidepressant action) on neurochemical parameters related to norepinephrine, serotonin and gamma-aminobutyric acid (GABA) neurons have been investigated in the rat and mouse brain. When given acutely, fengabine (50-1000 mg/kg i.p.) does not alter norepinephrine uptake but accelerates the turnover rate of norepinephrine in the rat brain as demonstrated by the enhancement of: the alpha-methyl-p-tyrosine-induced disappearance of norepinephrine in the hypothalamus; 3,4-dihydroxyphenylacetic acid levels in noradrenergic cell body areas; the pargyline-induced accumulation of normetanephrine in the hypothalamus; and 3,4-dihydroxyphenylethyleneglycol levels in the hypothalamus, septum and spinal cord. No tolerance to the effect of fengabine on the latter biochemical parameter was observed after repeated treatment for 2 weeks at doses of 100 or 200 mg/kg i.p., b.i.d. Fengabine (100 or 200 mg/kg i.p., b.i.d.), given for 14 days, causes a desensitization of isoprenaline-stimulated adenylate cyclase in septal and cortical slices of the rat but fails to modify cortical beta, alpha-1 or alpha-2 adrenoceptor binding sites. Fengabine (up to 400 mg/kg i.p.) has no effect on rat cerebral serotonin uptake, synthesis or metabolism. Moreover, when given subacutely (100 or 200 mg/kg i.p., b.i.d. for 2 weeks), it fails to alter rat cortical serotonine receptors or [3H]imipramine binding sites. Fengabine (up to 50-100 microM) is also inactive in vitro on [3H] GABA binding to GABAA or GABAB receptors in the rat brain or on GABA transaminase activity in the mouse brain.(ABSTRACT TRUNCATED AT 250 WORDS)

Measurement of 5-HIAA levels in ventricular CSF (by LCEC) and in striatum (by in vivo voltammetry) during pharmacological modifications of serotonin metabolism in the rat.

The relationship between the concentrations of 5-hydroxyindoleacetic acid (5-HIAA) in the CSF and in the striatum has been evaluated in the rat by measuring the levels of this metabolite in ventricular CSF (by liquid chromatography coupled with electrochemical detection) and in the striatal extracellular fluid (by in vivo voltammetry) after administration of inhibitors of serotonin synthesis or degradation. Pargyline, NSD 1015 and alpha-propyldopacetamide all caused an exponential decline of 5-HIAA in both CSF and striatum. For a given drug, the rate constants for 5-HIAA disappearance were identical in the CSF and in the striatal extracellular fluid. These results confirm the view that CSF 5-HIAA may serve as a good index of brain serotonin turnover.

Monoamine abnormalities in the brain of scrapie-infected rats.

The effects of the scrapie agent on the levels of monoamines and their metabolites, and on choline acetyltransferase (CAT) activity have been investigated in discrete brain areas in the rat. Two strains of scrapie (8745 from sheep brain and C506 M3 from mice brain) were inoculated. Scrapie-infected rats showed a reduction in the levels of serotonin (prefrontal cortex, hippocampus, striatum) and dopamine (striatum) and an elevation of 5-HIAA levels (cerebral cortex, striatum, thalamus). Noradrenaline levels were decreased only in the cerebral cortex and cerebellum of rats infected with the scrapie strain C506 M3. CAT activity remained unchanged. These data suggest that the scrapie agent causes a derangement of noradrenergic, serotonergic and dopaminergic systems in the rat brain.

Two-way avoidance and acute shock stress induced alterations of regional noradrenergic, dopaminergic and serotonergic activity in Roman high- and low-avoidance rats.

Various brain regions of male RHA/Verh and RLA/Verh rats were dissected out and deep-frozen immediately after 30 min in a shuttle box involving a) no shock (control), b) 40 inescapable shocks or c) 40 avoidable shocks. The RHA/Verh rats used in the "c" category exhibited about 80-85% learned avoidance. 5-HT, 5-HIAA, NA, MHPG-SO4, DA, DOPAC and HVA levels were subsequently measured in selected regions. NA levels were considerably reduced in the hypothalamus and pons/medulla of both selected lines of rats after acute shock stress, supporting the results of numerous studies which have indicated that NA turnover is nonspecifically increased by all types of stress, at least in those regions. An increase in cortical MHPG-SO4 and a reduction in hypothalamic 5-HT seen after avoidance learning also occurred after shock stress in RHA/Verh rats. Whereas RLA/Verh rats showed an increased metabolism of 5-HT in the hypothalamus and pons/medulla after shock stress, RHA/Verh rats showed the opposite response in the hypothalamus after the same treatment. A reduction in 5-HT metabolism was also evident in RHA/Verh rats, after avoidance learning, in the cortex, hippocampus and hypothalamus. These results indicated, pending further studies regarding, for example, possible genetic differences in tryptophan uptake and utilization, that 5-HT probably plays at least a modulatory role in the reaction to stress, and in avoidance behavior. That role may be either active or passive, depending upon the emotional status of the subjects. In regard to the DA responses measured in striatum and hypothalamus of the two rat lines, some divergent inter-treatment tendencies, as well as some similarities, were seen in DA metabolism in both regions, but almost none of the differences were significant.

Alterations of noradrenaline and serotonin uptake and metabolism in chronic cobalt-induced epilepsy in the rat.

The high affinity uptake of noradrenaline and serotonin, and the concentrations of these monoamines and their metabolites, have been measured in the perifocal cortical area at various stages of the evolution of cobalt-induced epilepsy in the rat. Noradrenaline uptake was maximally reduced at days 8-10 after cortical cobalt application, a time corresponding to the onset of epileptic discharges; it remained diminished during the spiking activity period of the focus (days 14-20) and was back to normal values at day 40, at which time the epileptic syndrome had disappeared. Serotonin uptake was also diminished at days 8-10 but to a lesser extent than was noradrenaline uptake. In the homotopic cerebral cortex contralateral to cobalt application, noradrenaline uptake was reduced at day 10 only and to a lesser extent than in the perifocal area, whereas serotonin uptake was unaffected. Kinetic analysis of the cobalt-induced monoamine uptake alterations at day 10 revealed a diminution of the maximal velocity with no change in the Km. Noradrenaline and dihydroxyphenylethyleneglycol concentrations in the perifocal area were also maximally reduced at days 8-10 but were unaffected at day 2 and day 40 post cobalt application. A reduction of serotonin levels in the perifocal area was observed only at days 8-10 while 5-hydroxyindoleacetic acid remained unaffected throughout the time period studied. The levels of these monoamines and their metabolites were unchanged in the homotopic contralateral cortex 2-40 days after cobalt application. These results indicate that cortical cobalt application induces alterations of the biochemical indices of the density of noradrenaline-containing terminals that closely parallel the evolution of the epileptic syndrome. These data further emphasize the important role of the cortical noradrenergic system in cobalt-induced epilepsy.