Jesper Johannes Madsen

Verocytotoxin-Producing Escherichia coli in Wild Birds and Rodents in Close Proximity to Farms

ABSTRACT Wild animals living close to cattle and pig farms (four each) were examined for verocytotoxin-producing Escherichia coli (VTEC; also known as Shiga toxin-producing E. coli). The prevalence of VTEC among the 260 samples from wild animals was generally low. However, VTEC isolates from a starling (Sturnus vulgaris) and a Norway rat (Rattus norvegicus) were identical to cattle isolates from the corresponding farms with respect to serotype, virulence profile, and pulsed-field gel electrophoresis type. This study shows that wild birds and rodents may become infected from farm animals or vice versa, suggesting a possible role in VTEC transmission.

Transmission of Salmonella between wildlife and meat-production animals in Denmark.

Aims:u2002 To investigate the transmission of Salmonella spp. between production animals (pigs and cattle) and wildlife on production animal farms in Denmark.

Campylobacter jejuni and Campylobacter coli in wild birds on Danish livestock farms

BackgroundReducing the occurrence of campylobacteriosis is a food safety issue of high priority, as in recent years it has been the most commonly reported zoonosis in the EU. Livestock farms are of particular interest, since cattle, swine and poultry are common reservoirs of Campylobacter spp. The farm environment provides attractive foraging and breeding habitats for some bird species reported to carry thermophilic Campylobacter spp. We investigated the Campylobacter spp. carriage rates in 52 wild bird species present on 12 Danish farms, sampled during a winter and a summer season, in order to study the factors influencing the prevalence in wild birds according to their ecological guild. In total, 1607 individual wild bird cloacal swab samples and 386 livestock manure samples were cultured for Campylobacter spp. according to the Nordic Committee on Food Analysis method NMKL 119.ResultsThe highest Campylobacter spp. prevalence was seen in 110 out of 178 thrushes (61.8xa0%), of which the majority were Common Blackbird (Turdus merula), and in 131 out of 616 sparrows (21.3xa0%), a guild made up of House Sparrow (Passer domesticus) and Eurasian Tree Sparrow (Passer montanus). In general, birds feeding on a diet of animal or mixed animal and vegetable origin, foraging on the ground and vegetation in close proximity to livestock stables were more likely to carry Campylobacter spp. in both summer (Pxa0<xa00.001) and winter (Pxa0<xa00.001) than birds foraging further away from the farm or in the air. Age, fat score, gender, and migration range were not found to be associated with Campylobacter spp. carriage. A correlation was found between the prevalence (%) of C. jejuni in wild birds and the proportions (%) of C. jejuni in both manure on cattle farms (R2xa0=xa00.92) and poultry farms (R2xa0=xa00.54), and between the prevalence (%) of C. coli in wild birds and the proportions (%) of C. coli in manure on pig farms (R2xa0=xa00.62).ConclusionsThe ecological guild of wild birds influences the prevalence of Campylobacter spp. through the behavioural patterns of the birds. More specifically, wild birds eating food of animal or mixed animal and vegetable origin and foraging on the ground close to livestock were more likely to carry Campylobacter spp. than those foraging further away or hunting in the air. These findings suggest that wild birds may play a role in sustaining the epidemiology of Campylobacter spp. on farms.

Surveillance for Avian Influenza Viruses in Wild Birds in Denmark and Greenland, 2007–10

SUMMARY. In Denmark and Greenland, extensive surveillance of avian influenza (AI) viruses in wild bird populations has been conducted from 2007 through 2010. In Denmark, the surveillance consisted of passive surveillance of wild birds found dead or sick across Denmark and active surveillance of apparently healthy live birds in waterfowl reservoirs and along migratory flyways, birds living in proximity to domestic poultry, and hunted game birds. Dead birds were sampled by oropharyngeal swabbing. Healthy live wild birds were captured with nets, traps, or by hand and were sampled by swabbing of the oropharyngeal and cloacal tracts, or swabs were collected from fresh fecal droppings. Hunted game birds were delivered to game-handling establishments, where each bird was sampled by oropharyngeal and cloacal swabbing. During the 2007–10 period, a total of 11,055 wild birds were sampled in Denmark, of which 396 were birds that were found dead. In Greenland, samples were collected mainly from fecal droppings in breeding areas. Samples from 3555 live and apparently healthy wild birds were tested. All swab samples were tested by pan-influenza reverse transcriptase–PCR (RT-PCR), and the positive samples were further tested by H5/H7 specific RT-PCRs. H5/H7-positive samples were subjected to hemagglutination cleavage site sequencing for pathotyping. In addition, all RT-PCR–positive samples were subjected to virus isolation, and the virus isolates were subsequently subtyped. In Denmark, low pathogenic (LP) H5 viruses were detected throughout the period, in addition to a few LPAI H7 and several other subtypes. In Greenland, very few samples were positive for AI. None of them were found to be of the H5 or H7 subtypes by RT-PCR. Isolation of these viruses in eggs was unsuccessful; thus, they were not subtyped further. The findings did, however, demonstrate the presence of LPAI viruses in Greenland. For several water bird species overwintering in North America and northwest Europe, respectively, Greenland constitutes a common breeding area. This raises the possibility that viruses could be transmitted to North America via Greenland and vice versa. In Denmark, the screenings for AI showed LPAI viruses to be naturally occurring in the wild bird population, particularly in waterfowl. The occurrence of AI viruses in the wild bird population may pose a risk for AI infections in Danish poultry.