Circadian Corticosterone Profile in Laying Hens (Gallus gallus domesticus).

Measurement of blood corticosterone concentrations has been established as an indicator for assessment of acute distress. Therefore, knowledge on physiological fluctuations is required, but previous studies allow little conclusion on daily fluctuations in domestic chickens (Gallus gallus domesticus). To verify the presence of a circadian corticosterone rhythm in socialized chickens, blood samples were taken at four-hour intervals from 12 laying hens kept in groups of four over three days, each. Prior to experiments, hens were adapted to repeated handling for stress reduction. Corticosterone concentration was determined using radioimmunoassay. Blood sampling time and duration were recorded, and audio and video recordings were analyzed to assess the impact of behavior on corticosterone concentrations. Despite individual fluctuations, most hens showed a circadian course with two peaks per day. Statistics revealed a significant peak during the day (between 12:00 p.m. and 04:00 p.m.) and a tendency for a second peak at night (12:00 a.m.). The daily corticosterone peak was not explained by daytime social stress and needs to be seen as an endophenotype. The role of nightly corticosterone production has to be investigated in further studies. There might be a relation between corticosterone and reproduction since the only hen not showing peaks was not laying eggs.

[Influence of the Verordnung über Tierärztliche Hausapotheken on antimicrobial use in dogs and cats in Bavaria]. / Einfluss der Verordnung über Tierärztliche Hausapotheken auf den Antibiotikaeinsatz bei Hund und Katze in Bayern.

OBJECTIVE: Aim of the study was to collect data concerning the use of antibiotics (AB) in dogs and cats in veterinary practices and clinics in Bavaria, Germany. It was evaluated, whether changes in the use of AB since the amendment of the Verordnung über Tierärztliche Hausapotheken (TÄHAV, German Regulation on the Veterinary In-house Pharmacy) in March 2018 could be documented. MATERIAL AND METHODS: Using 2 anonymous online surveys in 2017 and 2020, veterinarians treating dogs and cats in Bavaria were questioned about their usage of AB and their assessment of the current antimicrobial resistance situation. The results of both surveys were evaluated statistically and compared with each other. RESULTS: While in 2017 a total of 238 questionaries were evaluated, 160 could be included in 2020. The three most commonly used antibiotics for systemic therapy were Amoxicillin/Clavulanic acid (74.8 % of veterinarians), Enrofloxacin (56.7 %) and Amoxicillin (53.4 %) in 2017; and Amoxicillin/Clavulanic acid (88.8 %), Amoxicillin (67.5 %) and Metronidazole (33.8 %) in 2020, respectively. The participating veterinarians stated that their overall use of 3 rd and 4th generations cephalosporins (from 20.2 % of veterinarians in 2017 to 9.4 % in 2020, p = 0,005) as well as fluoroquinolones (from 80.3 % to 33.1 %, p < 0.001) had significantly declined. In 2020, the choice of AB in veterinarians was affected by legal requirements (83.8 %), tolerability (81.3 %), way of application (76.9 %), acceptance by the patient (70.0 %), and frequency of application (64.4 %), with the last parameter being significantly more important to veterinarians working in a practice (83.8 %, p = 0.004) than to veterinarians in a clinic. CONCLUSION: Veterinarians report a significantly reduced usage of fluoroquinolones and 3 rd and 4th generation cephalosporines in dogs and cats compared to 2017. These changes in prescribing practice could be a consequence of the amendment of the TÄHAV, which dictates a prohibition of rededication as well as an obligation for microbial sensitivity testing for these AB classes. CLINICAL RELEVANCE: Legal restrictions could have a positive influence on the amount and type of antibiotics used and therefore help to prevent antimicrobial resistance.

Canary Bornavirus (Orthobornavirus serini) Infections Are Associated with Clinical Symptoms in Common Canaries (Serinus canaria dom.).

While parrot bornaviruses are accepted as the cause of proventricular dilatation disease (PDD) in psittacine birds, the pathogenic role of bornaviruses in common canaries is still unclear. To answer the question of whether canary bornaviruses (species Orthobornavirus serini) are associated with a PDD-like disease in common canaries (Serinus canaria f. dom.), the clinical data of 201 canary bird patients tested for bornaviruses using RT-PCR assays, were analyzed for the presence of PDD-like gastrointestinal or central nervous system signs and for other viruses (mainly circovirus and polyomavirus), yeasts and trichomonads. Canary bornavirus RNA was detected in the clinical samples of 40 out of 201 canaries (19.9%) coming from 28 of 140 flocks (20%). All nucleotide sequences obtained could unequivocally be determined as canary bornavirus 1, 2, or 3 supporting the current taxonomy of the species Orthobornavirus serini. PDD-like signs were found associated with canary bornavirus detection, and to a lesser extent, with circoviruses detection, but not with the detection of polyomaviruses, yeasts or trichomonads. The data indicate that canary bornaviruses contribute to a PDD-like disease in naturally infected canaries, and suggest a promoting effect of circoviruses for the development of PDD-like signs.

Investigation of Meat from Ostriches Raised and Slaughtered in Bavaria, Germany: Microbiological Quality and Antimicrobial Resistance.

Ostrich meat is characterized by high nutritional value; however, it remains an exotic product in most countries worldwide. In Europe, only few data are available regarding its microbial contamination, prevalence of antimicrobial-resistant bacteria, and safety. Therefore, this study aimed to investigate the microbiological quality and safety of ostrich meat samples (n = 55), each from one animal, produced in Bavaria, Germany. The provided microbiological status of ostrich meat included mesophilic aerobic bacteria, Enterobacteria, and mesophilic yeast and molds. In terms of food safety, all meat samples were negative for Salmonella spp. and Trichinella spp. Additionally, meat samples and a further 30 stool samples from 30 individuals were investigated for Shiga toxin-producing Escherichia coli genes, with two meat samples that were qPCR-positive. Antimicrobial-resistant Enterobacteriaceae, Enterococcus faecalis, and Enterococcus faecium strains were from meat and stool samples also analyzed; 13 potentially resistant Enterobacteriaceae (meat samples) and 4 Enterococcus faecium (stool samples) were isolated, and their susceptibility against 29 and 14 antimicrobials, respectively, was characterized. The results of this study provide an overview of microbial loads and food safety aspects that may be used as baseline data for the ostrich meat industry to improve their hygienic quality. However, the implementation of monitoring programs is recommended, and microbiological standards for ostrich meat production should be established.

[X-Ray Dark-field radiography: Does this carry potential for diagnosing gout in exotic pets?] / Die Dunkelfeld-Radiografie ­ ein neuer Weg zur Diagnostik von Gichterkrankungen bei Vögeln und Reptilien?

OBJECTIVE: The aim of this study is to evaluate whether X-ray dark-field (DF) radiography is useful for the diagnosis of gout in birds and reptiles and whether this preclinical model could be helpful to establish this non-invasive imaging method in human medicine. MATERIAL AND METHODS: A total of 18 limbs originating from 11 birds (7 different species) and 7 reptiles (4 different species) with and without suspected joint gout were measured using a grating-based X-ray dark-field setup and conventional X-ray examination, respectively. Each image acquisition generated a dark-field and a conventional absorption x-ray image. The results of the individual scans were compared with the results of a pathological examination and arthrocentesis. RESULTS: In 5 of the birds and 4 of the reptiles examined, gout was detected by pathologic examination. In each group, uric acid crystals were found in the joints of 3 animals by means of arthrocentesis. The uric acid crystals were detectable in 2 bird and 2 reptile limbs in the dark-field image. CONCLUSION: The study demonstrated that the urate crystals evoke a clearly visible dark field signal, whereas this was not the case in the conventional radiographs. CLINICAL RELEVANCE: The results obtained show that uric acid crystal detection using less invasive imaging methods in an animal model with birds and reptiles may expand gout diagnostics not only in veterinary medicine but also in human medicine and possibly replace arthrocentesis if a DF signal is detectable. Preclinical scanners which use X-ray dark-field and phase-contrast radiography already exist for hands and mammography.

Spread of West Nile Virus and Usutu Virus in the German Bird Population, 2019-2020.

West Nile virus (WNV) and Usutu virus (USUV) are important flaviviruses circulating in Germany. While USUV was first reported more than 10 years ago, WNV has only reached the country in 2018. Wild birds are important amplifying hosts for both viruses. Therefore, we have been monitoring the bird population in different regions of Germany by a previously established network for many years. This report summarizes the results of molecular and/or serological methods of 2345 blood samples from birds of 22 different orders and over 2900 bird carcasses from 2019 and 2020. USUV RNA circulation was found in different regions of Germany, with emphasis on USUV lineages Europe 3 and Africa 3. Increased evidence of USUV lineage Europe 2 was detected in eastern Germany. WNV RNA was found only in birds from the eastern part of the country. The seroprevalence for USUV was between 3.11% and 7.20% in all three regions investigated, whereas the WNV seroprevalence spanned from 14.77% to 16.15% in eastern Germany, with a noticeable tendency for a westward and southward expansion in both years. Thus, wild bird monitoring for WNV and USUV can serve as an early warning system for a human exposure risk.

Penetration of Enrofloxacin in Aqueous Humour of Avian Eyes.

Enrofloxacin has been shown to be appropriate to treat bacterial eye infections in mammals. However, the anatomy and physiology of the avian eye substantially differ from those in mammals, and pharmacokinetic data substantiating the clinical efficacy of enrofloxacin in birds are still lacking. In total, 40 chickens (Gallus gallus, Lohman Selected Leghorn) received single intramuscular administration of enrofloxacin at a dosage of 25 mg/kg body weight (BW). Serial blood and aqueous humour samples were taken at 12 different time points after administration (0-60 min and 2-32 h) and were analysed for their fluoroquinolone concentrations using a competitive enzyme immunoassay. The metabolization of enrofloxacin to ciprofloxacin was determined using liquid chromatography-mass spectrometry. The maximum serum concentrations of fluoroquinolones were observed at the time point of 2.82 ± 0.1 h and amounted to 10.67 ± 0.5 µg/mL. Fluoroquinolones redistributed to a minor extent into the aqueous humour reaching maximum concentrations of 4.52 ± 1.2 µg/mL after 7.54 ± 1.0 h of drug administration. The mean residence time (MRT), volume of distribution (Vd), and terminal half-life (t1/2 ß) were 1.68-, 2.84-, and 2.01-fold higher in aqueous humour than in serum, indicating that fluoroquinolones were trapped in aqueous humour. Enrofloxacin was only marginally metabolized into ciprofloxacin. A single intramuscular injection of a therapeutical dose of enrofloxacin (25 mg/kg BW) thus generated sustained and therapeutically active levels of enrofloxacin in the aqueous humour of chicken eyes.

X-ray dark-field radiography for in situ gout diagnosis by means of an ex vivo animal study.

Gout is the most common form of inflammatory arthritis, caused by the deposition of monosodium urate (MSU) crystals in peripheral joints and tissue. Detection of MSU crystals is essential for definitive diagnosis, however the gold standard is an invasive process which is rarely utilized. In fact, most patients are diagnosed or even misdiagnosed based on manifested clinical signs, as indicated by the unchanged premature mortality among gout patients over the past decade, although effective treatment is now available. An alternative, non-invasive approach for the detection of MSU crystals is X-ray dark-field radiography. In our work, we demonstrate that dark-field X-ray radiography can detect naturally developed gout in animals with high diagnostic sensitivity and specificity based on the in situ measurement of MSU crystals. With the results of this study as a potential basis for further research, we believe that X-ray dark-field radiography has the potential to substantially improve gout diagnostics.

Development and Application of the Owner-Bird Relationship Scale (OBRS) to Assess the Relation of Humans to Their Pet Birds.

Only a few birds besides domestic pigeons and poultry can be described as domesticated. Therefore, keeping a pet bird can be challenging, and the human-avian relationship will have a major influence on the quality of this cohabitation. Studies that focus on characterizing the owner-bird relationship generally use adapted cat/dog scales which may not identify its specific features. Following a sociological approach, a concept of human-animal relationship was developed leading to three types of human-animal relationship (impersonal, personal, and close personal). This concept was used to develop a 21-item owner-bird-relationship scale (OBRS). This scale was applied to measure the relationship between pet bird owners (or keepers) (n = 1,444) and their birds in an online survey performed in Germany. Factor analysis revealed that the relationship between owner and bird consisted of four dimensions: the tendency of the owner to anthropomorphize the bird; the social support the bird provides for the owner; the empathy, attentiveness, and respect of the owner toward the bird; and the relationship of the bird toward the owner. More than one quarter of the German bird owners of this sample showed an impersonal, half a personal, and less than a quarter a close personal relationship to their bird. The relationship varied with the socio-demographic characteristics of the owners, such as gender, marital status, and education. This scale supports more comprehensive quantitative research into the human-bird relationship in the broad field of human-animal studies including the psychology and sociology of animals as well as animal welfare and veterinary medicine.

[Phenotypical antibiotic resistances of bacteriological isolates originating from pet, zoo and falconry birds]. / Phänotypische Antibiotikaresistenzen von Bakterienisolaten aus Zier-, Zoo- und falknerisch gehaltenen Greifvögeln.

OBJECTIVE: The prevalence of resistant bacteria in pet birds, zoo birds and falconry birds is still largely unknown. Therefore, antibiograms of rapidly-growing aerobic bacteria obtained from these birds were retrospectively evaluated. MATERIAL AND METHODS: Between 2007 and 2016 a total of 1036 antibiograms were evaluated. The bacteria isolates originated from 811 birds of 20 zoological orders (mostly Psittaciformes [61.8 %] and Passeriformes [14.5 %] and from alive patients or pathological examinations. The birds were primarily kept in Southern Germany. Phenotypic in vitro sensitivity of bacterial isolates to various antibiotics was determined using a standardized agar diffusion test. RESULTS: The most frequently examined bacteria species were Escherichia coli (n = 386 isolates), Staphylococcus (S.). aureus (n = 150), Enterobacter cloacae (n = 122), Klebsiella pneumoniae (n = 86) and Pseudomonas aeruginosa (n = 64). Resistance to at least one antibiotic agent was detected in 53.1 % of the E. coli isolates, most commonly to doxycycline (50.3 %) and ampicillin (46.1 %), as well as in 95.9 % of Enterococcus faecalis isolates and 78.0 % of Staphylococcus aureus isolates. Multidrug resistance to 3 or more antibiotic groups was frequent in S. aureus (37.3 % of isolates). Resistance rates were higher in isolates from pet birds and captive birds of prey than in isolates from zoo birds.Resistant isolates were more common in Psittaciformes than in Passeriformes. An increasing resistance rate for fluoroquinolones in E. coli (a minimum of 0 % in 2005 and a maximum of 27.3 % in 2011) and decreasing resistance rates for tetracyclines in S. aureus (a maximum of 38.2 % in 2007 and lowest values of 0 % in 2014 and 2015) were observed over the examined period. CONCLUSION AND CLINICAL RELEVANCE: The detected resistance rates of bacteria in pet birds, zoo birds and falconry birds must be considered as being problematic. They indicate the importance of microbial sensitivity testing for a conscientious therapy of pet birds, zoo birds and falconry birds. Critical treatment situations may arise from infections with S. aureus.