Investigations of the health condition of Canada geese (Branta canadensis, Linnaeus 1758) in North Rhine- Westphalia on the basis of an analysis of eggs | Untersuchungen zum Gesundheitsstatus von Kanadagänsen (Branta canadensis, Linnaeus, 1758) in Nordrhein-Westfalen an Hand der Analyse von Eiern Recherches sur l'état sanitaire d'oies du Canada (Branta canadensis, Linnaeus 1758) en Rhénanie- Westphalie sur base d'analyses d'oeufs

107 eggs of Canada geese from clutches within the environs of the recreational area of “Saaler Mühle” in North Rhine-Westphalia were morphometrically, microbiologically, and serologically analyzed. Investigations for the following pathogens or their antibodies were conducted: (i) zoonoses (Salmonella sp.,Campylobacter sp.,Chlamydia sp.) (ii) the antibodies to or the pathogens causing epidemics (virus of Newcastle Disease, Influenza A-Virus of haemagglutinin (HA-)- Subtypes H5 and H7); (iii) pathogens or their antibodies of primary diseases of waterfowl (Riemerella sp.,Pasteurella sp.,Escherichia coli, mold and yeast fungi, Paramyxovirus for the Serotypes 4 and 6, Egg-Drop Syndrome 1976, and duck plague herpes virus.Salmonella could not be culturally isolated from embryos, egg yolks, and egg membranes. Neither could Chlamydia be verified using HELA cell cultures.The isolation of pathogens for virally caused animal epidemics (Newcastle Disease and Fowl Pest was unsuccessful. A proof of the presence of antibodies to Newcastle Disease could only be shown in samples of egg yolks from 9 eggs. Antibodies to the Influenza A-Virus of the HA-Subtype H5 could only be determined in the yolk of one egg, and antibodies against the Influenza A-Virus HA -Subtype H7 could only be verified from 2 eggs.The cultural isolation of pathogens causing primary bacterial diseases of waterfowl could only be verified forPasteurella sp. (one egg),Escherichia coli (one egg), andStaphylococcus sp. (23 eggs).Various molds were isolated from 6 eggs. The cultural propagation of yeasts was unsuccessful.From one egg (Nr. 102) a virus belonging to the group of avian reoviruses was isolated. Antibodies against the Paramyxovirus Serotype 4 could not be detected. In 4 egg yolk samples antibodies against the Paramyxovirus Serotype 6 were found. Antibodies against the Egg-Drop Syndrome-1976 Virus were found in 20 egg yolk samples. A total of 14 yolk samples contained antibodies against the herpes virus of duck plague. The Hepatitis B virus of geese could not be determined with PCR.No pathogenic agents causing infectious diseases harmful to people were found.The demonstrated pathogens/antibodies of waterfowl epidemics and diseases present a potential danger for domestic poultry as well as for a few other species of wild birds. Careful observation of the Canada geese population and further investigations are necessary.