Background: In domestic animals (sheep and rats), is already known to have hepatotoxic effects of Echium plantagineum alkaloids (pyrrolizidine). These alkaloids and their metabolites can cause hemorrhagic liver dystrophy in the liver. Objectives: In exotic ruminants, such as the Mhorr gazelle (Nanger dama), no data on similar cases were found in the literature. Thus, this report describes the first case of Echium toxicosis in a dama Mhorr gazelle. Material and methods: The gazelle carcass found dead in the open area was necropsied and histopathological examination of liver and kidneys was performed according to paraffin embedding standard methods. E. plantagineum, flourished in large numbers as undergrowth of cork oak grove forest in the habitat of the animal, was collected and identified. Result and discussion: The authors found a dead Mhorr gazelle (Nanger dama) carcass in a paraoak forest near Rabat where purple viper's bugloss (Echium plantagineum) formed a significant, continuous vegetation. During the necropsy, the authors found hemorrhagic, toxic liver dystrophy with severe bleeding, sometimes destroying large area of the parenchyma, and dilation of urinary space of Bowman's capsule in the glomeruli of the kidney, as well as leakage of red blood cells. The pathological changes found may have been caused by the liver-damaging effect of the plant's pyrrolizidine alkaloids and their metabolites, known in other animal species. In connection with the case found in Morocco, since the occurrence of E. plantagineum is already known in our country, in the case of hemorrhagic liver dystrophy, this poisoning should also be considered from a differential diagnostic point of view.

Dirofilaria immitis is a worldwide spread, mosquito-borne nematode of zoonotic concern, with domestic and wild canids serving as the main reservoirs of the infection in Europe. In this study we describe eleven cases of cardiovascular dirofilariosis in Hungarian zoos, including three Eurasian wolves (Canis lupus lupus), two Arctic wolves (Canis lupus arctos), an African lion (Panthera leo), an African leopard (Panthera pardus pardus), a Red panda (Ailurus fulgens), an Arctic fox (Vulpes lagopus), a Harbour seal (Phoca vitulina), and an Asian small-clawed otter (Aonyx cinereus). Heartworm disease presumably contributed to the deaths of three Eurasian wolves, one Red panda, one Arctic fox and one Harbour seal, as indicated by necropsy results, whereas the remaining infections were regarded as incidental findings. These cases represent the first documented occurrence of D. immitis in captive felids in Hungary and the first report of D. immitis in Arctic wolves. The present case series provides data about host range of dirofilariosis and discusses their potential role as reservoirs of the infection in autochthonous wild animals in Europe underlining the need for implemented surveillance and preventive strategies in zoo animal populations.

Arthropod molting hormones, the so-called ecdysteroids were experimentally shown to have anabolic effects in higher vertebrates, promoting energy supply, protein synthesis, and tissue growth. Insectivorous songbirds (Aves: Passeriformes) and bats (Mammalia: Chiroptera) were demonstrated to have naturally acquired ecdysteroids in their blood. However, it is not known if partly insectivorous or artificially insect-fed vertebrates would also have ecdysteroids in their circulation. The aim of this screening study was to clarify this, by collecting blood samples of mammals, birds and reptiles that are wild-living or receive insect diet at zoological gardens, followed by ultra-high performance liquid chromatography and high-resolution quadrupole-orbitrap mass spectrometry analyses. The zoo animal samples originated from one reptilian species (n = 3), as well as one species of insectivorous mammals (n = 8), three species of carnivores (n = 17) and one species of primates (n = 2). Three further species of road-killed mammalian carnivores were sampled postmortem (n = 15). Finally, blood samples were also drawn and analyzed from six species of water-associated (n = 44) and three species of predatory birds (n = 47). Ecdysteroids were detected in two out of 136 samples: from a Common Kestrel (Falco tinnunculus) that contained 58.9 nM 20-hydroxyecdysone (20E), and from a beech marten (Martes foina) that contained 40.9 nM dacryhainansterone (a phytoecdysteroid). Although these concentrations do not mean evidence for sustained biological or anabolic effects, 20E was reported to transactivate estrogen receptors β and α with EC50 values of 13.0 and 25.7 nM, respectively. Accordingly, our results show for the first time that ecdysteroids may be present in pharmacologically relevant concentrations in the blood of predominantly carnivorous species of birds and mammals. However, unlike in songbirds and bats which continuously feed on insects, detectable levels of ecdysteroids appear only rarely in the blood of opportunistic insectivores, therefore their health benefits remain questionable in artificially and occasionally insect-fed zoo animals.

Background: In addition to domestic birds, lymphoma is also known in exotic species, it is particularly common in parrots and songbirds, but it can also occur in other species, so the form of the tumor localized to the skin has also been described in peacocks. Basically, two forms are known, B- and T-cell lymphoma. In the event when immature lymphoid cell elements also appear in the blood circulation, we are talking about a leukemic form. If only the organs are filtered by the lymphoid cell population, then we are dealing with an aleukemic form. Lymphoid cells infiltrating and proliferating in organs significantly change the basic tissue structure (creating atrophy and degeneration in the parenchymal cell populations), causing partial or even complete dysfunction of the organ or organ system. Liver involvement is very common in ornamental birds, which can be accompanied by liver enlargement (hepatomegaly), and leads to liver failure due to loss of hepatocyte function. When the kidney is affected, excretion is disturbed in all cases, and the removal of toxins and waste products is delayed. Objectives: The authors were the first in Hungary to describe a T-cell, aleukemic, multicentric lymphoma in mountain quail. Materials and Methods: The Mountain quail was dissected according to the rules of diagnostic examination, histopathological sections were prepared from the organs showing changes, and CD3 immunohistochemical reaction was performed. Blood smear was examined with Giemsa staining, and an aerobic bacteriological examination was performed on the liver. Small parts from the organs (liver, kidney) of the bird's carcass were pooled and used for PCP -based detection of the genetic material of some viruses (circo, polyoma, herpes and retrovirus). Results and Discussion: Due to the proliferation of lymphoid cells, the liver and the kidneys became enlarged, and due to the atrophy of the parenchyma, these two organs also lost their detoxification function. In other organs, such as the glandular stomach and the testicle, lymphoid cell proliferation could be detected by histological examination. The tumor cells gave a positive reaction in the CD3 immunohistochemical test, based on which the T-cell line lymphoma could be confirmed. It was not possible to detect with the PCR test the genetic material of circoviruses, polyomaviruses, herpesviruses and retroviruses that often play an oncogenic role in birds. Thus, in our case, the viral background could not be verified.

Parasitic crustaceans represent a significant threat to both freshwater and marine aquaculture, with several families capable of inducing severe diseases with high mortality rates and therefore significant economic losses. Among them, isopods of the genus Braga (Cymothoidae) are haematophagous parasites of neotropical fish, causing anaemia, tissue damage, and mortality. Braga nasuta , endemic to Brazil, has been reported from various hosts, including ornamental species exported worldwide. During routine examination of imported cardinal tetra ( Paracheirodon axelrodi , Schultz, 1956), the authors detected that one of the fish harbored an adult male isopod (∼6.21 mm long, 2.66 mm wide) attached anterior to the dorsal fin. Based on morphological identification, the parasite was identified as Braga nasuta . No secondary pathogens were observed in affected fish. Given the global trade in ornamental species, the introduction of B. nasuta into non-native regions underscores the importance of quarantine and parasite monitoring. While the potential ability of this parasite to establish populations in Europe requires further studies, vigilance is warranted to prevent potential spread and ecological impact. In this study, the authors document the first occurrence of B. nasuta in Europe, detected on a cardinal tetra ( P. axelrodi ) imported to a Hungarian public aquarium.

Introduction: Bats are one of the most important reservoirs of zoonotic pathogens, carrying many viruses such as coronaviruses, filoviruses, lyssaviruses, etc. Rabies virus, the most known representative of the Lyssavirus genus poses a significant threat to public health worldwide, with a nearly 100% mortality rate amongst humans. The European Bat Lyssavirus-1 (EBLV-1) is the most widespread Lyssavirus species in European bats that also occurs in Hungary. Our main goal was to establish a passive surveillance system for bat-borne viruses in Hungary, and to study the bat lyssavirus situation in the country. Methods: Samples were donated mostly by Hungarian bat rehabilitation centres and national park directorates as well as bat workers and researchers. Dead-found or injured/ill bats that died despite of the utmost care were subjected for investigation. Bats were identified by professionals and necropsy was carried out to sample different organs. For Lyssavirus screening, RNA was extracted from the brain, and pan-lyssa nested-RT-PCR was performed. In case of positivity, the samples were sequenced on Illumina platform after viral enrichment. Complete genomes were de novo assembled and manually error corrected. Results: More than 200 bats were received in the frame of our program between 2018 and 2023. Till date 84 individuals of 11 bat species were necropsied. Out of the examined animals we detected two positive samples originated from Serotine bats (Eptesicus serotinus). Sanger sequencing showed that the viruses belong to EBLV-1, which was further confirmed by whole genome sequencing. The new genomes are close to the published ones from Hungary and belong to the EBLV-1a strain. Interestingly, one of the infected bats was transferred to a rehabilitation centre because a frog captured it. It was kept for months in captivity without any sign of illness from a disease, and suddenly died in a few days in rabies. Discussion: Passive surveillance is an important method to study viruses circulating in the bat fauna, and as most bats found are from urban areas, this especially applies for the study of bats close to humans. According to our experience, it is worth to record as much information about the circumstances of the finding of the bat as possible, as it may be indicative for the presence of pathogens. Our results are congruent with former works as Serotine bat is the main host of EBLV-1. The virus is still present and circulating among these animals in Hungary. Conclusion: Passive surveillance systems are important and effective methods to study bat-borne virus circulation among these flying mammals, especially in urban settings. In the frame of our study, we have found Serotine bats which were infected with the European Bat Lyssavirus. Two new complete genomes of EBLV-1a strain were retrieved from the brains of these bats.

Although the clinical course and pathogenesis of lymphocystis disease virus (LCDV) infection have been extensively described in freshwater and seawater environments, lymphocystis disease has not been studied in the copperband butterflyfish (Chelmon rostratus) or described at the molecular level in orbicular batfish (Platax orbicularis). The present study aimed to identify LCDV in a copperband butterflyfish and an orbicular batfish using light and electron microscopy (morphological) and molecular methods, namely PCR followed by phylogenetic analysis. We present a case series of two representatives of two distinct fish species with stress-induced chronic LCDV infection, which presented with typical, recurring, macroscopically visible lymphocystis nodules on their pectoral, caudal, and dorsal fins. After collecting lymphocystis nodules from live animals using skin scraping, we processed the hypertrophic giant cells for qualitative analysis using light and electron microscopy. Through our qualitative morphological analysis, we also share intimate observations of putative viral replication and assembly in the intracytoplasmic inclusion bodies of lymphocystis nodules. We present LCDV infection in a novel species, the copperband butterflyfish, and our molecular analysis identified the virus from the orbicular batfish as a novel LCDV species.

Avian pox is a globally spread viral disease affecting a wide spectrum of wild and domesticated bird species. The disease is caused by a diverse group of large DNA viruses, namely, avipoxviruses (genus Avipoxvirus, family Poxviridae). In this study, gross pathological examination and histopathological examination of skin lesions and several organs suggested acute poxvirus infection of a Eurasian crane (Grus grus, Linnaeus, 1758). Avipoxvirus infection was confirmed by testing wart-like lesions via gene-specific PCR assay and sequencing the obtained amplicon. Phylogenetic analysis of the gene encoding the DNA polymerase revealed that the crane poxvirus clustered in clade A, subclade A3. A large fragment of the poxvirus genome (306,477 bp in length) was assembled from the DNA of a skin specimen. Our study reaffirms previous findings that even complex virus genomes can be determined from a metagenomic assemblage generated directly from avian tissue samples without prior virus isolation, a promising approach for the epidemiologic surveillance of avipoxvirus infections in wild birds and domestic poultry.

Background: The barn swallow (Hirundo rustled) is a migratory bird with a characteristic color, shiny black on the back, dirty white feathers on the belly, rust-red throat, weighing 17-20 g. This species mainly hunts flying insects, catching them in flight and the swallows are constantly hunting in the air between sunrise and sunset. As the food-scarce autumn season approaches, swallows gather in large flocks and when the daytime temperature drops permanently below 15 degrees C, they leave for their wintering grounds in Africa. The birds are preparing for the migration, replenishing their body's fat depots. By the time of leaving, the birds reach a body weight of 22-25 g, which enables them to travel thousands of kilometers. The metabolism of birds is fast, which is especially noticeable in smaller species. Shortterm starvation is already associated with a significant deterioration in nutritional status. Objectives: The carcasses of the swallows that were still alive at the time of capture, but died during transport were examined to identify to cause of sudden death. Materials and Methods: On September 16, 2024, 34 immobile and flightless swallows were delivered to the Clinic of the Department of Exotic Animal and Wildlife Medicine from the beach in Csopak, Hungary (46 degrees 58' 10.4 '' N, 17 degrees 56' 13.9 '' E). Five randomly selected carcasses of swallows were examined according to the standard pathological methods (dissection, histopathology, special stainings, bacteriological examination, PCR). Results and Discussion: During the dissection the body weight of the swallows delivered to the clinic was 12.0-13.0 g (12.6 g on average) which is around half of the normal bodyweight of these birds before migration. The supplementary examinations were negative for known pathogens and histopathology showed extreme lack of glycogen. According to the weather data from 11th of September 2024, a cyclone with significant cooling and heavy rainfall hit Hungary. The reason behind the death of the swallows was starvation caused by the sudden disappearance of the population of flying insects that could be caught by swallows due to cold and rainy weather. This case draws attention to the dangers of sudden extreme effects of global climate change in the case of some sensitive animal populations.

A szerzők hazánkban elsőként írtak le T-sejtes, aleukaemiás, multicentrikus lymphomát hegyi fürjben. A lymphoid sejtek burjánzása miatt a máj és a vesék megnagyobbodtak és a parenchyma sorvadása miatt a méregtelenítő funkcióját is elvesztette ez a két szerv. Egyéb szervekben mint a mirigyesgyomorban és a herében kórszövettani vizsgálattal lehetett lymphoidsejt-burjánzást kimutatni. A daganatos sejtek pozitív reakciót adtak a CD3 immunhisztokémiai vizsgálatban, ami alapján a daganat T-sejtes eredetét lehetett igazolni. A PCR-vizsgálattal nem lehetett kimutatni a circovírusok, a polyomavírusok, a herpeszvírusok és a madarakban gyakran onkogén tulajdonságú retrovírusok genetikai anyagát, így a vírusos háttér nem volt igazolható.

Acipenserid species play an important role in aquaculture. Emerging viral diseases can cause high mortality on farms. During our investigations, Siberian sturgeon herpesvirus (SbSHV) was detected on a fish farm in Hungary rearing Russian sturgeon (Acipenser gueldenstaedtii) and Siberian sturgeon (Acipenser baerii). Herpesvirus infection may result in mortality rates up to 100% in young animals; on the other hand, adults usually suffer much less mortality. The affected fingerlings initially showed neurological symptoms and lost their appetite. Opaque deposits and haemorrhages were observed on the skin. After necropsy, samples were taken for virological and bacteriological investigation. A broad-spectrum PCR, developed for the detection of acipenserid and ictalurid herpesviruses (genus Ictavirus), was applied. The sequence analysis of the detected PCR fragment showed high identity to a previously described SbSHV strain originating from Russia. There is currently neither a cure nor an effective vaccine available on the market against this disease. Therefore, prevention and strict biosecurity protocols are the most important ways to keep the animals healthy.

In late November 2021, a male serval (Leptailurus serval) which had escaped from an unknown holding facility was observed in the Bükk Mountains of Northern Hungary. A few days were needed to capture the animal with a live trap, after which it was transported to a national Rescue Centre at the Budapest Zoo and Botanical Garden. The exact origin of the specimen was never identified and apart from being emaciated, it seemed only to be stressed and weakened by the cold weather and starvation. Contrary to the initial fair prognosis, 2.5 days after admittance, the animal rapidly developed pronounced respiratory and central nervous system signs and despite intensive treatment died within a few hours. The subsequent diagnostic investigation revealed that the cause of death was SARS-CoV-2 infection. These diagnostic steps excluded other possible, lethal felid pathogens as causative agents and confirmed that the disease process was attributed to this virus.

This the first report on the presence of Ehrlichia cf. ewingii in a reindeer (Rangifer tarandus) in Hungary. The animal started to show apathy and loss of appetite and subsequently died shortly after being placed in an enclosure with dense vegetation, following a quarantine period. During the diagnostic necropsy, a large volume of reddish pericardial and thoracic effusion was observed resembling heartwater disease. Ehrlichia cf. ewingii was detected from the thoracic effusion by PCR and sequencing. The selenium content of multiple organs (liver, kidney, heart and skeletal muscles) were measured, but no increase was found. PCR tests for the detection of adenoviruses from the liver, lungs and spleen were negative. The routine bacteriological culture from the liver did not yield specific results either. To establish a causal relationship between the presence of E. cf. ewingii and the animal's death, further investigations are necessary.

In a preliminary survey study, the authors measured intraocular pressure in the right and left eye of 63 (32 females and 31 bucks) 3-8 month old, clinically healthy European brown hares (Lepus europaeus, Pallas, 1778). The mean intraocular pressure was 25.35 millimeters of mercury (mmHg) (n = 63), 25.4 mmHg for bucks and 25.3 mmHg for females. The average standard deviation was 4.86. The difference in intraocular pressure (IOP) between rabbits aged 3-5 months and 6-8 months was not significant, nor was the difference between females and bucks.

Background: Tarantulas (or bird-eating spiders), as exotic pets, have long been kept in Hungary. Nevertheless, our knowledge regarding their pathogens remains limited. Viruses, bacteria, mites and endoparasitic nematodes have been associated with tarantula diseases. Among the latter, members of the Tarantobelus genus, specifically Tarantobelus arachnicide and Tarantobelus jeffdanielsi deserve particular attention. Both species can infect tarantulas, causing similar clinical symptoms, most commonly manifesting as loss of appetite. Another characteristic symptom is the appearance of a white secretion around the mouth opening and chelicerae. Materials and methods: In the autumn of 2024, a Chilobrachys dyscolus (SIMON, 1886) tarantula was presented at the Clinic of the Department of Exotic Animal, Wildlife, Fish, and Bee Health at the University of Veterinary Medicine, Budapest. According to the owners, the spider had a loss of appetite. After observation in an awake state, the animal was anesthetized using 5% isoflurane gas mixture with an oxygen flow rate of 2000 cc/min. Following anesthesia, matting of the hairs and the presence of a white secretion around the mouth opening and chelicerae were observed. The oral cavity of the spider was rinsed with warm physiological saline solution. The collected rinse fluid contained small, worm-like structures, approximately 1 mm in size. Conventional light microscopy confirmed the presence of helminth infection, prompting further examination at the Parasitology and Zoology Laboratory of the University of Veterinary Medicine. The nematodes were treated with approximately 24% lactic acid and subsequently examined under light microscope. Results and Discussion: With the light microscopic examination, the detected nematodes were classified within the Tarantobelus genus. The morphological characteristics of male and female parasites found and their reproductive structures were the same as the worms that we lavaged from the spider's mouth. Our case was the first diagnosed infection in a tarantula.

Bats are vital parts of ecosystems but also act as important reservoirs of viruses that can infect humans. Studying bat-borne viruses is essential for preventing spillover events, and passive surveillance offers a promising, bat-friendly approach. Among these viruses, lyssaviruses are a major public health concern because infection in humans is almost always fatal. In Europe, the European bat lyssavirus type 1 (EBLV-1) is the most widespread. We aimed to expand the Hungarian rabies surveillance system into a One Health-based passive surveillance framework for multiple bat viruses, using lyssaviruses and filoviruses as examples. Dead-found or injured bats that died despite care were collected for examination. In total, 208 bats from 15 species were tested for lyssaviruses and Lloviu virus. Three serotine bats (Cnephaeus serotinus, formerly Eptesicus) tested positive for EBLV-1, and complete viral genomes were obtained. All sequences belonged to the EBLV-1a lineage, closely related to previously described Hungarian strains. All bats tested negative for Lloviu virus. These results confirm the feasibility of passive surveillance for detecting bat-borne viruses and highlight the importance of collaborative monitoring systems for future zoonotic outbreak preparedness.

Background: Mycoplasmosis in reptiles, which requires some predisposing factors, was first confirmed in a tortoise showing clinical signs. In Hungary, mycoplasmosis has been described in turtles, tortoises and also in a ball python (Python regius). Mycoplasma infection is also known worldwide in other species, such as green iguanas (Iguana iguana). Sometimes the animals are asymptomatic. Mycoplasmosis has already been described in a bearded dragon, in which M. pogonae has been detected. Objectives: To the authors' knowledge mycoplasmosis has not yet been described in bearded dragons in Hungary. The authors were the first to investigate the case and clarify its postmortem lesions. Materials and Methods: The lizard presented to the clinic was returned home after clinical examination and sampling, but it died the next night. Subsequently, autopsy was performed, samples were taken for histopathological and bacteriological examinations. PCR testing was also performed to detect mycoplasma infection. Results and Discussion: Acute rhinitis, tracheitis with epithelial degeneration and pneumonia accompanied by muco-serous fluid accumulation were found at autopsy. During the PCR test, bacteria with 76% overlap on the 165 rRNA - 235 rRNA intergenic spacer region of M. iguanae were isolated. In the presented case, inadequate feed was identified as a predisposing factor in the properly housed, bearded dragon. The case is considered to be the first case and description of mycoplasmosis in Hungary in this lizard species.

A csirkék mirigyesgyomor-elhalását okozó birnavírusa (chicken proventricular necrosis virus, CPNV) az elsősorban brojlercsirkékben ismert átoltható mirigyesgyomor- gyulladás nevű kórkép feltételezett kóroka. A szerzők tudomásuk szerint elsőként igazolták a CPNV-fertőzést pettyes fogasfürjben. Az esetleírás célja, hogy felhívja a figyelmet az egyéb, tyúkalakúak közé tartozó madárfajok esetleges szerepére a vírus járványtanában. A szerzők egy pettyes fogasfürj tetemét vizsgálták makroszkópos és mikroszkópos vizsgálattal, rutin bakteriológiai, ill. molekuláris biológiai módszerekkel. A mirigyesgyomor-mintát kilenc vírus jelenlétére vizsgálták, amelyek közül csak a CPNV-re adott pozitív eredményt a PCR-vizsgálat.

Diagnostic imaging techniques provide a new aspect of the ante-mortem and post-mortem diagnostics in fish medicine. Ultrasonography, computed tomography (CT) and magnetic resonance imaging (MRI) can provide more information about the internal organs and pathognomic lesions. The authors used diagnostic imaging techniques to evaluate and describe the neoplastic malformation in a 3-year-old female rainbow trout (Oncorhynchus mykiss). The fish was examined with Siemens Somatom Definition AS + CT scanner and Siemens Biograph mMR scanner. The animal was lethargic and showed anorectic signs and muscular dystrophy. During the post-mortem investigation, histopathology and immunohistochemistry were also performed allowing us to identify the neoplasms. The results showed a large soft tissue mass in the first mid-intestine segment, which proved to be an adenocarcinoma. This subsequently led to digestion problems and absorption disorders. Immunohistochemically, neoplastic cells of carcinoma revealed E-cadherin and pancytokeratin positivity. This is the first study to report the use of MRI and CT for studying gastrointestinal adenocarcinoma in rainbow trout.

Polyomaviruses are widely distributed viruses of birds that may induce developmental deformities and internal organ disorders primarily in nestlings. In this study, polyomavirus sequence was detected in kidney and liver samples of a common kestrel ( Falco tinnunculus ) that succumbed at a rescue station in Hungary. The amplified 5025 nucleotide (nt) long genome contained the early (large and small T antigen, LTA and STA) and late (viral proteins, VP1, VP2, VP3) open reading frames (ORFs) typical for polyomaviruses. One of the additional putative ORFs (named VP4) showed identical localization with the VP4 and ORF-X of gammapolyomaviruses, but putative splicing sites could not be found in its sequence. Interestingly, the predicted 123 amino acid (aa) long protein sequence showed the highest similarity with human papillomavirus E4 early proteins in respect of the aa distribution and motif arrangement implying similar functions. The LTA of the kestrel polyomavirus shared <59.2% nt and aa pairwise identity with the LTA sequence of other polyomaviruses and formed a separated branch in the phylogenetic tree among gammapolyomaviruses. Accordingly, the kestrel polyomavirus may be the first member of a novel species within the Gammapolyomavirus genus, tentatively named Gammapolyomavirus faltin .