24 research outputs found
Occurrence and Characteristics of Escherichia albertii in Wild Birds and Poultry Flocks in Switzerland
Escherichia albertii, a zoonotic pathogen, has sporadically been associated with infectious diarrhea in humans. Poultry and wild birds are considered potential reservoirs. We assessed the occurrence of E. albertii in 280 fecal samples from wild birds (n = 130) and pooled fecal samples collected at slaughterhouse level from poultry flocks (n = 150) in Switzerland. Using an E. albertii-specific PCR targeting the Eacdt gene, 23.8% (31/130) of the samples from wild birds, but not from the pooled poultry fecal samples, tested positive for Eacdt. The positive samples originated from 11 bird species belonging to eight families. Strain isolation was attempted on the PCR-positive samples by subculturing the broth cultures onto xyloseâMacConkey plates. Isolation was possible on 12 of the 31 Eacdt-PCR-positive samples. Whole-genome sequencing revealed that the strains belonged to nine distinct sequence types, with ST13420 and ST5967 being represented by two and three isolates, respectively. All strains harbored the eae gene, while two strains were also positive for stx2f. Our study thus shows that E. albertii is present in the Swiss wild bird population, which can potentially act as a source of this pathogen to humans, other animals, and the environment
Screening of Healthy Feral Pigeons (Columba livia domestica) in the City of Zurich Reveals Continuous Circulation of Pigeon Paramyxovirus-1 and a Serious Threat of Transmission to Domestic Poultry
Pigeon paramyxovirus-1 (PPMV-1) is predominantly isolated from pigeons or doves and forms a separate group of viral strains within Avian Orthoavulavirus-1, the causative agent of Newcastle disease in poultry. Since the introduction of PPMV-1 into Europe in 1981, these strains have rapidly spread all over Europe, and are nowadays considered to be enzootic in feral and hobby pigeons (Columba livia domestica). Infections with PPMV-1 can range from asymptomatic to fatal. To assess whether PPMV-1 continuously circulates in healthy feral pigeons, 396 tissue samples of pigeons from the city of Zurich were tested by reverse transcriptase real-time PCR over the period of one year. PPMV-1-RNA was detected in 41 feral pigeons (10.35%), determined as the dominant European genotype VI.2.1.1.2.2. In 38 of the 41 pigeons where organ samples tested positive, PPMV-1-RNA was also detected in either choana or cloaca swabs. There were no significant differences in positivity rates between seasons, age, and sex. The current study shows that feral pigeons without clinical signs of disease can harbour and most likely excrete PPMV-1. Spill-over into free-range holdings of chickens are therefore possible, as observed in a recent outbreak of Newcastle disease in laying hens due to PPMV-1 genotype VI.2.1.1.2.2. in the canton of Zurich in January 2022
Screening of Healthy Feral Pigeons (Columba livia domestica) in the City of Zurich Reveals Continuous Circulation of Pigeon Paramyxovirus-1 and a Serious Threat of Transmission to Domestic Poultry.
Pigeon paramyxovirus-1 (PPMV-1) is predominantly isolated from pigeons or doves and forms a separate group of viral strains within Avian Orthoavulavirus-1, the causative agent of Newcastle disease in poultry. Since the introduction of PPMV-1 into Europe in 1981, these strains have rapidly spread all over Europe, and are nowadays considered to be enzootic in feral and hobby pigeons (Columba livia domestica). Infections with PPMV-1 can range from asymptomatic to fatal. To assess whether PPMV-1 continuously circulates in healthy feral pigeons, 396 tissue samples of pigeons from the city of Zurich were tested by reverse transcriptase real-time PCR over the period of one year. PPMV-1-RNA was detected in 41 feral pigeons (10.35%), determined as the dominant European genotype VI.2.1.1.2.2. In 38 of the 41 pigeons where organ samples tested positive, PPMV-1-RNA was also detected in either choana or cloaca swabs. There were no significant differences in positivity rates between seasons, age, and sex. The current study shows that feral pigeons without clinical signs of disease can harbour and most likely excrete PPMV-1. Spill-over into free-range holdings of chickens are therefore possible, as observed in a recent outbreak of Newcastle disease in laying hens due to PPMV-1 genotype VI.2.1.1.2.2. in the canton of Zurich in January 2022
On the reproductive biology of the Fossa (Cryptoprocta ferox)
Die Fossa (Cryptoprocta ferox Bennet, 1833) gehört zu der Familie Herpestidae
und ist das gröĂte endemische Raubtier Madagaskars. Als einziger natĂŒrlicher
Feind der groĂen Lemurenarten spielt sie eine potentiell wichtige Rolle im
RĂ€uber-Beute System der Insel. Seit 2002 wird sie auf der roten Liste der
bedrohten Tierarten gefĂŒhrt. Die Fossa ist ein monöstrischer EinzelgĂ€nger mit
einer kurzen Paarungszeit im FrĂŒhjahr. In der vorliegenden Studie sollte die
europÀische Zoopopulation durch reproduktionsbiologische Parameter
beschrieben, saison- und geschlechtsspezifische Unterschiede erfasst und der
reproduktive Gesundheitsstatus erhoben werden. Hierzu wurden ĂŒber den Zeitraum
von zwei Jahren 16 mÀnnliche und 15 weibliche Fossas aus zehn europÀischen
Zoos, und somit ĂŒber 50% des europĂ€ischen Zoobestandes, meist zu beiden
Saisons - Paarungszeit (PZ) und Nicht-Paarungszeit (NPZ) - untersucht. Die
KörpermaĂe der Fossa wurden erfasst und der Penis detailliert beschrieben.
Kranial des Skrotums wurde eine Erhebung entdeckt, die ultrasonographisch als
zweilappige, in der Haut gelegene DrĂŒse identifiziert und angesichts ihrer
Lage als PraeskrotaldrĂŒse bezeichnet wurde. Das Hodenvolumen und die LĂ€nge des
Os penis wurden vermessen und dabei festgestellt, dass beide GröĂen mit dem
Alter zunehmen. Das weibliche Genitale wurde auf das Vorkommen von Os clitoris
und Klitorisstacheln untersucht und bei Vorkommen beider Merkmale das
entsprechende Tier als maskulinisiert eingestuft. Das Os clitoris wurde
aufgrund seiner geringen GröĂe ultrasonographisch dargestellt und vermessen -
die LĂ€nge nahm mit dem Alter ab. Die ultrasonographische Darstellung und
Vermessung der inneren Geschlechtsorgane und -drĂŒsen zeigten eine Tendenz zu
gröĂeren Volumina in der PZ; bei weiblichen Tieren wurde eine
Follikelanbildung auf den Ovarien festgestellt. Zu den pathologischen Befunden
zÀhlten der unilaterale Kryptorchismus sowie Zysten und schlechte AusprÀgung
des weiblichen Genitaltrakts. Die Hormonanalysen spiegelten die
ultrasonographischen Befunde wider. Bei der Kothormonanalyse zeigten die
MÀnnchen, zwei nicht-trÀchtige sowie das trÀchtige Weibchen die höchsten
Konzentrationen der gemessenen Sexualhormonmetabolite (Dihydrotestosteron bzw.
5alpha-Progesteron) innerhalb der PZ. Die Werte des trÀchtigen Weibchens
ĂŒberstiegen dabei die Konzentrationen der nicht-trĂ€chtigen um ein Vielfaches
und blieben bis kurz nach der Geburt auf einem deutlich erhöhten Niveau. Im
Kot zweier weiterer nicht-trĂ€chtiger Weibchen wurden ĂŒber den Jahresverlauf
keine deutlichen Ănderungen der Sexualhormonmetabolite festgestellt. Die
Bluthormonanalyse wies bei MÀnnchen höhere Testosteronwerte als bei Weibchen
nach; saisonal waren diese bei MĂ€nnchen in der PZ und bei Weibchen in der NPZ
erhöht. Die bei Weibchen gemessenen Estrogenwerte waren in der PZ erhöht, die
Progesteronwerte in der NPZ. Die spermatologische Untersuchung umfasste die
Erhebung der klassischen Ejakulat-Parameter sowie die ultrastrukturelle
Beschreibung der Fossa-Spermien. Es zeichnete sich eine Tendenz zu höheren
Ejakulatvolumina, höherer MotilitÀt und geringerer Spermienkonzentration in
der PZ ab. Morphologisch konnten fĂŒnf Kopftypen abgegrenzt werden, welche
saisonal zu unterschiedlichen prozentualen Anteilen im Ejakulat vorkamen. Im
Weiteren war in der PZ eine Tendenz zu lÀngeren Spermien festzustellen. Die
Duftstoffanalyse an Fossa-Haaren zeigte saison- und geschlechtsspezifische
Duftstoffmuster und es konnten einige geschlechtsspezifische Substanzen
identifiziert werden.The Fossa (Cryptoprocta ferox Bennet, 1833) belongs to the family herpestidae
and is the largest endemic carnivore on Madagascar. It is the only predator of
large lemur species and thus plays a potential key role in the predator-prey-
relationship of this island. Since 2002 the fossa is listed in the red list of
endangered species. The fossa is a solitary animal with a brief breeding
season in spring. The aim of the present study was to describe the European
zoo population using reproductive parameters; seasonal and gender specific
differences were to be detected and the reproductive health to be evaluated.
Over the period of two years, 16 male and 15 female fossas of ten European
zoos, and thus over 50% of the European zoo population, were assessed during
both seasons: the breeding season (BS) and the non-breeding season (NBS). The
body size was depicted using morphometric measurements and the morphology of
the penis was described in detail. A two-lobed gland was detected in the skin
cranial to the scrotum and named by its location as "prescrotal gland". The
testical volume and the length of the Os penis were measured; the size of both
structures increased with the age of the animal. The female genitals were
inspected for the existence of an Os clitoris and clitoridal spikes; animals
exhibiting both traits were classified as masculinised. Due to its small size,
the Os clitoris was visualised and measured using ultrasonographic imaging:
the length of the Os clitoris decreased with the age of the animal. The
ultrasonographic analysis of the internal reproductive organs and sexual
glands showed a tendency towards larger volumes during the BS; in female
animals ovarian follicles were detected. The reproductive organs showed
several pathologies such as unilateral cryptorchism, cysts of the female
genital tract or poor development of female reproductive organs. The hormone
analysis refl ects the ultrasonographical findings. The assessment of faecal
steroid metabolites (dihydrotestosterone, 5alpha-progesterone) showed in males
as well as in two non-pregnant and one pregnant females the highest
concentrations during the BS. In the pregnant animal the concentrations
exceeded the values of non-pregnant animals significantly and stayed elevated
until shortly after parturition. The annual pattern of faecal steroid
metabolites of the remaining two non-pregnant females did not show any
significant changes in concentration. The analysis of serum testosterone
showed higher values in males than in females with seasonally higher values in
the BS for males and the NBS for females. The levels of estrogen were higher
during BS and of progesterone during NBS - both hormones were measured in
females only. The spermatological analysis included the assessment of the
classical semen parameters as well as the description of the ultra structure
of fossa spermatozoa. The volume of the ejaculate and the motility of the
spermatozoa were increased during the BS while the sperm-concentration was
decreased. The morphological analysis revealed five different sperm-head
categories showing a seasonal difference in abundance. Additionally, there was
a tendency towards a greater total length in spermatozoa during the BS. The
analysis of volatiles in fossa hair showed seasonal and gender specific
patterns and a number of gender specific substances were identified
Chlamydiaceae in wild, feral and domestic pigeons in Switzerland and insight into population dynamics by Chlamydia psittaci multilocus sequence typing
Feral pigeons, common wood pigeons and Eurasian collared doves are the most common representatives of the Columbidae family in Switzerland and are mostly present in highly populated, urban areas. Pigeons may carry various members of the obligate intracellular Chlamydiaceae family, particularly Chlamydia (C.) psittaci, a known zoonotic agent, and C. avium. The objective of the study was to identify the infection rates of common free-roaming pigeons for different Chlamydia species with the overall aim to assess the risk pigeons pose to public health. In this study, 431 pigeons (323 feral pigeons, 34 domestic pigeons, 39 Eurasian collared doves, 35 common wood pigeons) from several geographic locations in Switzerland were investigated for the presence of Chlamydiaceae. Samples consisted of pooled choanal-cloacal swabs (n = 174), liver samples (n = 52), and paired swab and liver samples from 205 pigeons (n = 410). All 636 samples were screened using a Chlamydiaceae family-specific 23S rRNA real-time PCR (qPCR). Subsequent species identification was performed by DNA-microarray assay, sequencing of a 16S rRNA gene fragment and a C. psittaci specific qPCR. In total, 73 of the 431 pigeons tested positive for Chlamydiaceae, of which 68 were positive for C. psittaci, four were C. avium-positive and one pigeon was co-infected with C. avium and C. psittaci. The highest infection rates were detected in feral (64/323) and domestic pigeons (5/34). Common wood pigeons (2/35) and Eurasian collared doves (2/39) revealed lower infection rates. Additionally, multilocus sequence typing of twelve selected C. psittaci-positive samples revealed closely related sequence types (ST) between and within different Swiss cities. Furthermore, liver and corresponding swab samples from the same bird were colonized by the same ST. Considering the high infection rates of C. psittaci in domestic and feral pigeons, close or frequent contact to these birds poses a human health risk
Occurrence of Chlamydiaceae in Raptors and Crows in Switzerland
Bacteria of the family Chlamydiaceae are globally disseminated and able to infect many bird species. So far, 11 species of Chlamydia have been detected in wild birds, and several studies found chlamydial strains classified as genetically intermediate between Chlamydia (C.) psittaci and C.abortus. Recently, a group of these intermediate strains was shown to form a separate species, i.e., C.buteonis. In the present study, 1128 samples from 341 raptors of 16 bird species and 253 corvids representing six species were examined using a stepwise diagnostic approach. Chlamydiaceae DNA was detected in 23.7% of the corvids and 5.9% of the raptors. In corvids, the most frequently detected Chlamydia species was C.psittaci of outer membrane protein A (ompA) genotype 1V, which is known to have a host preference for corvids. The most frequently detected ompA genotype in raptors was M56. Furthermore, one of the raptors harbored C.psittaci 1V, and two others carried genotype A. C.buteonis was not detected in the bird population investigated, so it remains unknown whether this species occurs in Switzerland. The infection rate of Chlamydiaceae in corvids was high compared to rates reported in other wild bird species, but neither Chlamydiaceae-positive corvids nor raptors showed overt signs of disease. Since the Chlamydiaceae of both, raptors and crows were identified as C.psittaci and all C.psittaci genotypes are considered to be zoonotic, it can be suggested that raptors and crows pose a potential hazard to the health of their handlers
Inconspicuous post-mortem findings in rabbits from Switzerland naturally Âinfected with Rabbit Haemorrhagic ÂDisease Virus 2
Rabbit Haemorrhagic Disease Virus 2 (RHDV-2) emerged in France in 2010. In Switzerland, RHDV-2 was first identified in 2015 and apparently has almost replaced the classical Rabbit Haemorrhagic Disease Virus (RHDV) by now. Like RHDV, RHDV-2 causes a viral hepatitis with a peracute course and an increased mortality rate within the rabbitry. RHDV infection causes consistent gross pathological findings, especially in the liver and respiratory tract. Reports about gross pathology for animals naturally infected with RHDV-2 is scarce. The present study analysed the anamnesis and necropsy reports of 35 rabbits examined during routine diagnostics between March 2015 and May 2017. A reverse transcriptase real-time polymerase chain reaction (RT-qPCR) specific for RHDV-2 and RHDV proved a total of 25 animals to be positive for RHDV-2, while none was positive for RHDV. Additionally, histological examinations were performed on liver, lung, and kidney of 18 rabbits that had tested positive by RHDV-2 RT-qPCR. The anamnestic report more often stated an increased mortality rate in RHDV-2 positive (16/18, 89 %) compared to RHDV-2 negative rabbits (3/9, 33 %). Gross pathology did not reveal any pathognomonic changes in RHDV-2 positive animals. Histologically, the liver showed the most severe lesions followed by lung and kidney. Animals positive for RHDV-2 frequently showed signs of gastro-intestinal disease (n = 5) and/or septicaemia (n = 6) masking possible indicators of an RHDV-2 infection, such as the rather unspecific findings of an enlarged spleen or an enlarged, friable, tan-coloured liver. The authors want to raise awareness among clinicians and pathologists that in case of sudden death in commercial or pet rabbits, RHDV-2 needs to be considered as differential diagnosis and should be confirmed by laboratory diagnosis
Antimicrobial resistant and extendedâspectrum ÎČâlactamase producing Escherichia coli in common wild bird species in Switzerland
A total of 294 fecal swabs from 294 wild birds in Switzerland were cultivated for antimicrobial resistant (AMR) Escherichia coli. Samples were also subcultivated to detect E. coli with extended-spectrum ÎČ-lactamases (ESBL), carbapenemases, and plasmid-mediated aminoglycoside or colistin resistance, respectively. Samples from 17 (5.8%) of the birds contained 19 AMR E. coli, whereof 26.3% were multidrug resistant. Five (1.7%) ESBL-producing E. coli were detected. The isolates harbored blaCTX-M-1 (two isolated from carrion crows and from one great spotted woodpecker, respectively), blaCTX-M-15 (originating from a grey heron), blaCTX-M-55 (from a carrion crow), and blaCTX-M-65 (from a common blackbird). Phylogenetic analysis assigned three isolates to commensal phylogroups A and B1, one to extraintestinal pathogenic group B2, and one to phylogroup F. Multilocus sequence typing identified sequence types (STs) that have been found previously in ESBL E. coli in wild birds (ST58, ST205, ST540). One isolate harboring blaCTX-M-55 was assigned to the recently emerged fluoroquinolone-resistant, extraintestinal pathogenic E. coli clone ST1193. Wild birds have the potential to disperse AMR, including clinically important resistance genes, from anthropogenic-influenced habitats to diverse areas, including vulnerable natural environments such as surface waters or mountain regions
Survey on Chlamydiaceae in cloacal swabs from Swiss turkeys demonstrates absence of Chlamydia psittaci and low occurrence of Chlamydia gallinacean
In Switzerland, domestic turkey meat is a niche product. Turkeys are fattened on mixed family-based farms scattered across the country, with most providing access to an uncovered outdoor pasture for the birds. Swiss fattening turkeys may therefore get infected with Chlamydiaceae via wild birds or their faeces, potentially shedding these bacteria at a later stage. The aim of the present study was to acquire baseline data about the shedding of Chlamydiaceae in clinically unremarkable Swiss fattening turkeys at slaughter, potentially exposing slaughterhouse workers to infection. In this large-scale study, 1008 cloacal swabs of Swiss turkeys out of 53 flocks from 28 different grow-out farms with uncovered outdoor pasture were collected over the course of 14 months and examined for the occurrence of Chlamydiaceae by a family-specific 23S-rRNA real-time PCR. Positive samples were further analyzed by Chlamydia psittaci (C. psittaci)-specific real-time PCR and the Arraymate DNA Microarray for species identification. All samples were negative for C. psittaci, but seven swabs out of one flock were tested positive for Chlamydia gallinacea (0.7%). Although turkeys with access to pasture may have contact with Chlamydiaceae-harbouring wild birds or their faeces, the infection rate in Swiss turkeys was shown to be low