Seroepidemological investigations on the distribution of European Brown Hare Syndrome (EBHS) and Rabbit Haemorrhagic Disease (RND) in the field hare populations of selected districts in the Federal Republic of Germany

During the investigations of 100 field hare sera from the year 1994 and 402 field hare sera from 1997 for antibodies to EBHSV (EBHSV-AK) using an anti body- ELISA 20 % respectively 10 % reagents could be determined. The blood samples came from freshly killed field hares from various districts in Hess e, neighboring Rhineland-Palatinate, as well as two districts not from this region. The determined titers - in 1994 up to 10000, in 1997 up to 100 - d iffered during these two periods. Significant differences in respect to the proportion of serological reagents were observed in the individual distric ts. A correlation between the number of reagents and the population density mostly assessed by headlight counting could not be determined. In the sera of 1994 with the hemagglutination inhibiting reaction (HAH) determined ant ibodies to RHDV were highly independent of the respective EBHSV-antibodies. For animals up to one year of age the frequency and amount of EBHSV-AK wer e the same as for old animals. The presented data show a decreased signific ance in the importance of EBHS for the field hare populations in the invest igated areas.