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Classical swine fever (CSF) in wild boar repeatedly appeared in different federal states of the Federal Republic of Germany since 1995, from which it has been successfully eradicated sometimes fast, sometimes in a more time taking way using oral immunization as a main element of control. Since 2005 the cases focused solely on North Rhine-Westphalia and Rhineland-Palatinate. In the present study, therefore, the situation of CSF in wild boar has been closely investigated concerning the period 2005 to 2012 in these two regions. It is noteworthy that in this period two different variants of the virus subtype 2.3 occurred in two regionally defined areas of the "Eifel" and "Westerwald" as well as in the "Pfalz". The two Federal States have undertaken extensive oral vaccination campaigns and surveillance activities, which enabled an assessment of the existing virus prevalence and serological prevalence in the different regions. After an initial high serological prevalence, caused probably by interaction of infection and vaccination, the serological levels stabilized seasonally adjusted in a range from 50 to 60% in almost all areas. The vaccination campaigns have been maintained by both Federal States over a period of at least 2.5 years after virus has been detected for the last time. In consequence Germany as a whole has been recognized for the first time to be officially free from CSF in wild boar. By genotyping of virus isolates it has been demonstrated that the virus changed over time and played a role in the outbreak area "Westerwald".

In recent foot and mouth disease outbreaks, many healthy animals have been culled to prevent disease transmission. Emergency vaccination is discussed as an alternative to culling of unaffected animals. A spatial and temporal Monte-Carlo simulation model was used to compare preventive culling and emergency vaccination. Different outbreaks are described using additional influence factors such as airborne spread, farm density, type of index-case farm and delay until establishment of the control strategies. The fewest farms were infected establishing a combined strategy including a 1 km preventive culling and 1-10 km emergency vaccination zone around each outbreak farm. Taking the number of culled and vaccinated farms into account, vaccination around the first diagnosed farm combined with the baseline strategy (culling of outbreak farms, protection and surveillance zone, contact tracing) is to be preferred. In the present study, emergency vaccination was an effective control strategy especially in densely populated regions., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

We conducted phylogenetic and epidemiologic analyses to determine sources of outbreaks of highly pathogenic avian influenza virus (HPAIV), subtype H5N1, in poultry holdings in 2007 in Germany, and a suspected incursion of HPAIV into the food chain through contaminated deep-frozen duck carcasses. In summer 2007, HPAIV (H5N1) outbreaks in 3 poultry holdings in Germany were temporally, spatially, and phylogenetically linked to outbreaks in wild aquatic birds. Detection of HPAIV (H5N1) in frozen duck carcass samples of retained slaughter batches of 1 farm indicated that silent infection had occurred for some time before the incidental detection. Phylogenetic analysis established a direct epidemiologic link between HPAIV isolated from duck meat and strains isolated from 3 further outbreaks in December 2007 in backyard chickens that had access to uncooked offal from commercial deep-frozen duck carcasses. Measures that will prevent such undetected introduction of HPAIV (H5N1) into the food chain are urgently required.

In the present study the effect of control measures implemented during the classical swine fever (CSF) epidemic in wild boar in the Eifel region of the German federal state of Rhineland-Palatinate from 1999 to 2005 was assessed. During the first 3 years after official confirmation of virus detection these measures comprised intensive hunting, especially of young animals and hygiene measures. Subsequently oral immunisation (o.i.) using a modified live virus vaccine was introduced as an additional control tool. All shot wild boar from the restricted area were tested virologically and serologically for CSF. The laboratory results from over 110,000 animals accompanied by information about age, gender and geographical origin of the animals were collected in a relational database. In total about 82% of all virologically positive wild boars were piglets, thus confirming the importance of this age group in the perpetuation of the epidemic. An analysis of the hunting bag showed that piglets were underrepresented compared to older animals throughout the eradication programme. This finding indicated that hunters did not comply with the control strategy of intense targeting of young animals. Before as well as after the implementation of o.i. a significantly higher virological prevalence and a significantly lower serological prevalence were observed in piglets compared to yearlings and adults. Shortly after the beginning of the vaccination campaign in February 2002 CSFV prevalence decreased significantly whereas the serological prevalence increased markedly in all age classes. In order to test the influence of age and vaccination on the serological prevalence a logistic regression model was used. Our results strongly suggest that under the field conditions in the Eifel region vaccination against CSFV had a crucial influence on the increase of seroprevalence rate and the elimination of CSFV. The last virus-positive pig was found 13 months after start of o.i.

The objective of this study was to investigate the maternal protection of gruntlings derived from wild sows vaccinated orally against classical swine fever (CSF) using C-strain vaccine. Three vaccinated sows and one unvaccinated control sow were included. Challenge infection of the progeny was carried out either intranasally or by contact at the beginning of the third month of life (61-65 days post-natum). Whereas, two of three litters had maternal antibodies, the progeny of one vaccinated sow was seronegative at challenge. The progeny of the control sow, which was challenged by contact infection, developed moderate clinical signs except for one animal which became ill and died. Two gruntlings derived from the vaccinated sows also died of CSF, although one of them had a relatively high maternal antibody titre (128 ND(50)). The transient infection and partial virus shedding observed in a small number of gruntlings with maternal antibodies and the fact that one animal with maternal antibodies became ill and died confirm the incomplete maternal protection at this age. The reason for this incomplete protection is discussed. As none of the surviving gruntlings could be shown to carry CSFV or viral RNA at the end of the experiment (36 or 70 d.p.i.), it may be concluded that these animals do not represent a potential CSFV reservoir.

In Germany, eleven outbreaks of CSF in domestic pig holdings were reported in 2002. They occurred exclusively in regions where CSF virus circulated in the wild boar population. In ten cases the phylogenetic analysis revealed that the isolates from domestic pigs and wild boar had identical sequences in the 5' non-translated region (5'NTR). However, in one case a subtype was isolated which was slightly different from the virus subtype found in the wild boar population of that region. This case is decribed in detail. The epidemiological significance of different diagnostic methods is discussed, in particular the genetic typing of CSF virus isolates.

The aim of the studies was to fathom the duration and the role of maternal immunity for Aujeszky's disease (AD) and classical swine fever (CSF) in wild boar offspring. In one experiment, two wild boar sows were infected with a low pathogenic pseudorabies virus (PRV) in 1999. A total of 51 offspring was born between 1999 and 2002 and was monitored for PRV maternal antibodies. In a second experiment, the maternal immunity for CSF was analysed. Therefore, a sow was orally vaccinated against CSF using vaccine baits containing the live-attenuated C-strain vaccine. The vaccination took place in January 1999. The sow gave birth to four piglets in 2001 and to two piglets in 2002. With respect to maternal immunity for AD, some piglets reacted positive in the ELISA up to 27-week post-partum while in the neutralization test antibodies were detected up to 15-week post-partum. The calculated half-life of neutralizing antibodies was 21 days. Regarding CSF, the neutralization titres of maternal antibodies dropped continuously reaching values of < or =10 ND50 20-week post-partum. After the 12th week post-partum, most of the sera reacted negative in the ELISA. However, after the third month, low levels of neutralization titres were still detectable. The results are discussed with respect to the epidemiology and control of both diseases in wild boar populations.

In Germany the last outbreak of Aujeszky's disease (AD) in a holding of domestic pigs had been officially confirmed in the year 2000, and, since February 2003 Germany is officially confirmed free of AD. Since this time the AD free status is monitored according to chapter II of the annex of the regulation for the protection against Aujeszky's disease. As an alternative monitoring protocol two variants of a two step random sampling scheme is proposed which reduces the sample size from a complete investigation of all domestic pig holdings to a sample of pig fattening and pig breeding farms. Within the random selected farms, pigs are sampled as usual according to chapter II of the annex of the regulation for the protection against Aujeszky's disease. In this paper, the measures to be taken in case of a positive AD result are discussed: In case of conformation of an AD suspicion it is proposed to establish a restriction area. In addition measures based on regionalisation are proposed in order to maintain the AD free status for areas outside established restriction areas. The proposed monitoring schemes potentiate an enormous reduction of sampling costs, but call for a revision of the regulation for the protection against Aujeszky's disease.

Objective: To determine susceptibility of European wild boars (Sus scrofa) to infection with pseudorabies virus (PrV) and to characterize the virulence of a wildboar PrV isolate for wild and domestic pigs., Animals: 18 wild boars and 16 domestic pigs., Procedure: Three groups of 4 wild boars were inoculated with PrV Bartha, Kaplan, and a wild-boar isolate (BFW1) and housed with uninfected pigs. Two groups of domestic pigs (4 and 8 pigs/group, respectively) were inoculated with various doses of BFW1. Animals were observed daily for clinical signs, and samples were tested for PrV excretion and homologous antibodies. After reactivation of latent infection by induced immunosuppression, PrV was detected in tissues of necropsied animals, using cell culture and a polymerase chain reaction (PCR)., Results: Clinical signs depended on virulence of the PrV strain and dose of inoculum. Only infection with PrV Kaplan resulted in severe disease and death. Virus was isolated from nasal and genital swab specimens. Antibodies were first detected on day 7 after inoculation; a specific humoral immune response was delayed in BFW1-infected animals. Virus was isolated from various tissues of Kaplan-infected wild boars, whereas mainly viral DNA was detected in a few tissues of Bartha- and BFW1-infected animals, using PCR after immunosuppression., Conclusions and Clinical Relevance: European wild boars are susceptible to transmission of PrV infection from domestic pigs and vice-versa. The PrV isolate BFW1 is of low virulence and seems to be adapted to the wild boar population from which it was isolated.

An experimental study was conducted to investigate the clinical course of classical swine fever (CSF) in wild boar piglets partially protected by maternal antibodies. Five healthy wild boar piglets with a low serum titre of colostral antibodies against CSF virus were challenged with virulent CSF virus at the age of three months. Apart of reduced food intake and diarrhoea no major clinical symptoms were noticed after challenge. These signs were seen during the second and third week of infection, afterwards the piglets recovered completely. CSF virus could be re-isolated from blood samples taken on day 12 and day 19 post challenge. From blood samples taken later on and from the organ material taken at post mortem examinations no CSF virus could be isolated anymore. It can be concluded that the presence of maternal antibodies influences the clinical course of CSF in terms that the outcome is rather transient than lethal. Such wild boar could play a crucial role in the spread of CSF virus and might contribute to the maintenance of long lasting epizootics.

Based on an experimental study using two and six PRRS-negative young boars and gilts, respectively, it was proven wether boar semen could be a risk factor in the transmission of the disease. The two boars were inoculated intranasally with the PRRS-virus strain I10 (Intervet) containing 107 TCID50/ml. Using ovulation synchronization six gilts were prepared as bioindicators to be inseminated, two of them with semen of the two boars at day 4, 8 and 12 after infection. Following inoculation of the boars, PRRS virus was shown to be present in blood from the 2nd until the 35th and 40th day p.i., respectively. PRRS virus could also be isolated from nasal swabs at day 6, 9, 12 and 19 and from preputial swabs at day 4, 12 and 27 after infection. PRRS virus could only be detected at day 19 p.i. in semen of one boar. Drastic changes in quality and volume of the ejaculate were observed about day 25 p.i. in both animals. Insemination of the gilts with semen collected at day 4, 8 and 12 p.i., however, did not lead to an infection of the females, because neither clinical signs typical for PRRS nor seroconversion could be observed. Reproductive parameters as well as birth and growing traits of the gilts were in accordance with norm values.

Since the first test in spring 1990, aerial distribution of baits has been developed as the main bait distribution variant in the new federal states of Germany. Experiences are given in respect of organisation, management and enforcement of oral immunization campaigns and cooperation between veterinary agencies and flight enterprises. Practical aspects are described to ensure bait density, preparation of maps, creation of technical preconditions and realisation of dropping rhythm. Aerial dropping in comparison with hand distribution of baits was shown to be equivalent at least in respect of bait uptake and seroconversion rate.

Three high-performance cows in lactation were tested each for the effects of two kinds of infusion each, 500 ml of Tetamag-2 solution (60 g of calcium gluconate and 60 g of magnesium adipate) and 500 ml of Calcimag (100 g of calcium gluconate and 20 g of magnesium adipate), upon the levels of calcium, magnesium, Pa, potassium, and sodium as well as upon the activities of aspartate-aminotransferase, leucine-aminopeptidase, and alkaline phosphatase in blood serum and upon glucose levels in blood plasma. Migration of calcium out of blood plasma was found to take place at much higher rate than that of magnesium. Infusion of Pa and glucose was followed soon by some temporary drop of values. No directional effects were recordable from potassium and sodium. Aspartate-aminotransferase activity did not change in response to transfusion. Intravenous infusion of Tetamag-2 solution caused strong temporary rise in magnesium concentration and, consequently, activation of leucine-aminopeptidase.

The levels of various compounds in blood serum and blood plasma were tested in 14 heads of cattle with hypomagnesiaemia (x = 0.76 +/- 0.29 mg/100 ml), prior to and following infusion of 500 ml of a calcium-magnesium solution (containing 60 g of magnesium adipate and 60 g of calcium gluconate). Concomitant hypocalcaemia (6.1 mg/100 ml) was recordable only from one animal. Most of the potassium as well as all Pa and protein values in blood serum were physiologically normal, while sodium ws somewhat reduced. The glucose level in blood plasma was increased in the animal with concomitant hypocalcaemia and in one animal with poor recovery potential. The drops in magnesium and calcium levels in blood serum, following infusion, in cattle with hypomagnesiaemia was very similar to that in clinically intact cattle. Aspartate-aminotransferase and creatinine-phosphokinase activities of the serum were increased in all cattle, but leucine-aminopeptidase activity in only some of them. The activity of alkaline phosphatase of the blood serum was physiologically normal.