Holger Andreas Volk

Holger Andreas Volk
University of Veterinary Medicine Hannover | TiHo · Klinik für Kleintiere

Professor DVM PhD PGCAP DipECVN

About

321
Publications
87,552
Reads
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5,036
Citations
Introduction
Holger is currently Professor of Small Animal Diseases and the Head of Department of Small Animal Medicine and Surgery, University of Veterinary Medicine Hanover and holds an Honorary Senior Lecturer position from University College, London and an Honorary Professorship in Veterinary Neurology and Neurosurgery at the Royal Veterinary College and an Affiliate Professor of Veterinary Neurology at University of Copenhagen.
Additional affiliations
January 2019 - present
University of Veterinary Medicine Hannover
Position
  • Head of Department
September 2004 - January 2019
Royal Veterinary College
Position
  • Head of Department
September 2004 - September 2016
Royal Veterinary College
Position
  • Professor (Full), Head of Department

Publications

Publications (321)
Article
Full-text available
Ataxia is an impairment of the coordination of movement or the interaction of associated muscles, accompanied by a disturbance of the gait pattern. Diagnosis of this clinical sign, and evaluation of its severity is usually done using subjective scales during neurological examination. In this exploratory study we investigated if inertial sensors in...
Article
Full-text available
Phenobarbital (PB) is one of the most important antiseizure drugs (ASDs) to treat canine idiopathic epilepsy (IE). The effect of PB on the taxonomic changes in gastrointestinal microbiota (GIM) and their functions is less known, which may explain parts of its pharmacokinetic and pharmacodynamic properties, especially its antiseizure effect and drug...
Article
Background: The treatment of canine adrenal insufficiency consists of hormone substitution and requires high owner compliance and intense human-dog interaction. This might affect the quality of life (QoL) of owners and their pets. The aim of the study was to evaluate the impact of hypoadrenocorticism and its treatment on the QoL of dogs and their...
Article
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To provide students of veterinary medicine with the necessary day 1 competences, e-learning offerings are increasingly used in addition to classical teaching formats such as lectures. For example, virtual patients offer the possibility of case-based, computer-assisted learning. A concept to teach and test clinical decision-making is the key feature...
Article
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Background: Nausea and emesis can be, among other signs, common manifestations of acute vestibular system dysfunction in dogs. Currently, antiemetic drugs, such as maropitant and metoclopramide, are used commonly, but do not appear to control nausea. A non-placebo-controlled preliminary study suggested good efficacy of 5-HT3-receptor antagonists,...
Article
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Background: Owners often feel the cost of veterinary care is too high, as there remains a limited understanding of the cost of health care in human and veterinary medicine alike. Pet health insurance is often seen as a universal solution. However, especially for patient owners with few financial resources, both the bill at the vet and the monthly...
Article
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A male 10-year-old captive red kangaroo (Macropus rufus) was presented with a chronic progressive pelvic limb lameness and reluctance to jump. The general examination revealed a palpable induration of the lumbar epaxial muscles. Magnetic resonance imaging performed under general anesthesia revealed bilateral almost symmetric, well-circumscribed mas...
Article
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Background This case report describes the clinical presentation, magnetic resonance imaging (MRI) as well as the histopathological findings in an elderly cat with an intracranial cholesterol granuloma. Case presentation An 11.5-year-old, male neutered cat was presented at the emergency service with deteriorating behavioral changes including aggres...
Article
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The oral palatability of functional foods such as medium-chain triglycerides (MCT) play a crucial role in owner and patient compliance when used as an adjunct in the management of health conditions such as epilepsy. Despite the promising benefits, the palatability of MCT has not undergone a more recent evaluation in dogs. The aim of this study was...
Article
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Modulation of neuronal activity for seizure control using various methods of neurostimulation is a rapidly developing field in epileptology, especially in treatment of refractory epilepsy. Promising results in human clinical practice, such as diminished seizure burden, reduced incidence of sudden unexplained death in epilepsy, and improved quality...
Article
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There is a growing number of COVID-19 patients experiencing long-term symptoms months after their acute SARS-CoV-2 infection. Previous research proved dogs' ability to detect acute SARS-CoV-2 infections, but has not yet shown if dogs also indicate samples of patients with post-COVID-19 condition (Long COVID). Nine dogs, previously trained to detect...
Article
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Autoantibodies against neurotransmitter receptors detected in cerebrospinal fluid (CSF) and serum are increasingly recognized in people with human autoimmune encephalitis causing severe neurological deficits, such as seizures and behavioral abnormalities. This case report describes the first encephalitis associated with antibodies against the γ-ami...
Article
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Epilepsy is the most common chronic neurological disease in humans and dogs. Epilepsy is thought to be caused by an imbalance of excitatory and inhibitory neurotransmission. Intact neurotransmitters are transported from the central nervous system to the periphery, from where they are subsequently excreted through the urine. In human medicine, non-i...
Article
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Status epilepticus (SE) can be effectively resolved if diagnosis and treatment are addressed at an early stage, although this is not always possible in clinical practice. If untreated, continuous seizure activity leads to refractory SE which does not respond to antiseizure medication. Although refractory SE is a life-threatening emergency, there is...
Article
We report the clinical, pathological and immunohistochemical characteristics of a phaeochromocytoma (PCC) in a 9-year-old male neutered Golden Retriever dog. The dog presented with acute onset of deteriorating cervical pain but was otherwise normal on general physical and neurological examinations. Magnetic resonance imaging of the cervical spine r...
Book
Full-text available
The new edition of this innovative textbook on clinical reasoning in veterinary medicine, provides a simple and logical approach for solving a wide range of clinical problems Clinical Reasoning in Veterinary Practice: Problem Solved! 2nd Edition continues to provide a revolutionary approach for rapidly and efficiently solving clinical problems enc...
Article
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Drug-resistant epilepsy is a common complaint in dogs and affects up to 30% of dogs with idiopathic epilepsy. Experimental data suggest that targeting cyclooxygenase-2 (COX-2) mediated signaling might limit excessive excitability and prevent ictogenesis. Moreover, the role of COX-2 signaling in the seizure-associated induction of P-glycoprotein has...
Article
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Background: Meningioma is the most common primary brain neoplasm in dogs. Further information is required regarding the expected long-term prognosis of dogs following the surgical resection of an intracranial meningioma together with the influence of adjunctive therapies. Whilst there have been several studies reporting the long-term outcome of in...
Article
Breed specific paroxysmal dyskinesias are increasingly recognised in veterinary medicine. We aimed to characterise the phenomenology, clinical course and prevalence of a previously unreported paroxysmal dyskinesia in the Welsh terrier breed. Clinical records of five Welsh terriers with paroxysmal episodes were reviewed. Additionally, owners of Wels...
Article
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Background: Dogs can be trained to identify several substances not detected by humans, corresponding to specific Volatile Organic Compounds (VOCs). The presence of VOCs, triggered by SARS-CoV-2 infection, was tested in sweat from long COVID patients. Patients and methods: An axillary sweat sample of long COVID patients and of COVID-19 negative, asy...
Article
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Background Different 3D-printed materials polyactic acid (PLA), polyamide (PA), polycarbonates (PC), acrylonitrile butadiene styrene (ABS) and GreenTEC Pro® I have been considered for surgical templates, but there is a sparity of data about how these materials are affected by steam sterilization. The aim of the current study was to test if and how...
Article
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We investigated a highly inbred family of British Shorthair cats in which two offspring were affected by deteriorating paraparesis due to complex skeletal malformations. Radiographs of both affected kittens revealed vertebral deformations with marked stenosis of the vertebral canal from T11 to L3. Additionally, compression of the spinal cord, cereb...
Article
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Background: Testing of possibly infected individuals remains cornerstone of containing the spread of SARS-CoV-2. Detection dogs could contribute to mass screening. Previous research demonstrated canines' ability to detect SARS-CoV-2-infections but has not investigated if dogs can differentiate between COVID-19 and other virus infections. Methods: T...
Article
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Objectives A previous single-country pilot study indicated serum anti-GM2 and anti-GA1 anti-glycolipid antibodies as potential biomarkers for acute canine polyradiculoneuritis. This study aims to validate these findings in a large geographically heterogenous cohort. Materials and Methods Sera from 175 dogs clinically diagnosed with acute canine po...
Article
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Deep Learning based Convolutional Neural Networks (CNNs) are the state-of-the-art machine learning technique with medical image data. They have the ability to process large amounts of data and learn image features directly from the raw data. Based on their training, these networks are ultimately able to classify unknown data and make predictions. M...
Article
We conducted a severe acute respiratory syndrome coronavirus 2 antibody seroprevalence study among >2,000 domestic cats from 4 countries during the first coronavirus disease wave in Europe. We found 4.4% seroprevalence using a virus neutralization test and 4.3% using a receptor-binding domain ELISA, demonstrating probable human-to-cat transmission.
Poster
Epilepsy is the most common chronic neurological disease in humans and dogs. Seizures greatly impact patients' and caretakers' quality of life. One of the caretakers' major concerns is that seizures may remain unnoticed or may be noticed too late. There is need for reliable detection of seizures in order to apply quick emergency treatment for preve...
Article
The aetiology of canine idiopathic vestibular syndrome (IVS) remains unclear. In human medicine, characteristic magnetic resonance imaging (MRI) techniques are used to demonstrate differences in endolymph composition between affected and unaffected inner ears. The purpose of this study was to determine whether similar MRI techniques could help to d...
Article
Full-text available
Circadian and other physiological rhythms play a key role in both normal homeostasis and disease processes. Such is the case of circadian and infradian seizure patterns observed in epilepsy. However, these rhythms are not fully exploited in the design of active implantable medical devices. In this paper we explore a new implantable stimulator that...
Article
Full-text available
The extraordinary olfactory sense of canines combined with the possibility to learn by operant conditioning enables dogs for their use in medical detection in a wide range of applications. Research on the ability of medical detection dogs for the identification of individuals with infectious or non-infectious diseases has been promising, but compar...
Article
Full-text available
Background The main strategy to contain the current SARS-CoV-2 pandemic remains to implement a comprehensive testing, tracing and quarantining strategy until vaccination of the population is adequate. Scent dogs could support current testing strategies. Methods Ten dogs were trained for 8 days to detect SARS-CoV-2 infections in beta-propiolactone...
Preprint
Full-text available
Circadian and other physiological rhythms play a key role in both normal homeostasis and disease processes. Such is the case of circadian and infradian seizure patterns observed in epilepsy. However, these rhythms are not fully exploited in the design of active implantable medical devices. In this paper we explore a new implantable stimulator that...
Article
We report a therapy cat in a nursing home in Germany infected with severe acute respiratory syndrome coronavirus 2 during a cluster outbreak in the home residents. Although we confirmed prolonged presence of virus RNA in the asymptomatic cat, genome sequencing showed no further role of the cat in human infections on site.
Article
Full-text available
In contrast to food-producing animals, where the documentation of the usage of antimicrobials is regulated by law, antimicrobial usage (AMU) in dogs and cats is only sparsely monitored. We collected data generated by an electronic practice management software (EPMS) between January 1, 2017 and December 31, 2018 to investigate AMU. All information w...
Article
Full-text available
Background Vestibular syndrome is often accompanied by nausea. Drugs currently approved for its treatment have been developed to stop vomiting but not nausea. The efficacy of 5-HT 3 receptor antagonists to reduce nausea has been described for chemotherapy, but not for nausea secondary to vestibular disorders. Methods Sixteen dogs with vestibular s...
Article
Full-text available
Many studies show that glucose metabolism in epileptic brain areas can be impaired. Energy is crucial to maintain normal brain function, including ion and neurotransmitter balances. Energy deficits can lead to disruption of ion gradients, which can trigger neuronal depolarization and generation of seizures. Thus, perturbed metabolic processing of g...
Article
Full-text available
An infection with the cat lungworm, Aelurostrongylus abstrusus, can be subclinical, but it can also cause severe respiratory clinical signs. Larvae excretion, antibody levels, clinical assessment findings of the respiratory system and diagnostic imaging findings were recorded and compared for six cats with experimental aelurostrongylosis. In five c...
Article
Full-text available
Background: Epilepsy is the most common chronic neurological disease in dogs that adversely affects the quality of life (QoL) of affected dogs and their owners. Research on epilepsy in dogs is expanding internationally, but where best to focus limited research time, funds, and expertise to achieve better outcomes for affected dogs and their owners...
Article
Full-text available
In recent years sensorineural hearing loss was found to affect not exclusively, nor at first, the sensory cells of the inner ear. The sensory cells’ synapses and subsequent neurites are initially damaged. Auditory synaptopathies also play an important role in cochlear implant (CI) care, as they can lead to a loss of physiological hearing in patient...
Article
Full-text available
Movement disorders are a heterogeneous group of clinical syndromes in humans and animals characterized by involuntary movements without changes in consciousness. Canine movement disorders broadly include tremors, peripheral nerve hyperexcitability disorders, paroxysmal dyskinesia, and dystonia. Of these, canine paroxysmal dyskinesias remain one of...
Article
Full-text available
Background Canine idiopathic epilepsy (IE) is the most common chronic neurological brain disease in dogs, yet it can only be diagnosed by exclusion of all other potential causes. In people, epilepsy has been associated with a reduction in brain volume. The objective was to estimate the volume of the forebrain (FB), subarachnoid space (SAS) and late...
Preprint
Full-text available
Background: The main strategy to contain the current SARS-CoV-2 pandemic remains to implement a comprehensive testing, tracing and quarantining strategy until vaccination of the population is adequate. Methods: Ten dogs were trained to detect SARS-CoV-2 infections in beta-propiolactone inactivated saliva samples. The subsequent cognitive transfer p...
Article
Full-text available
Status epilepticus (SE) or prolonged epileptic seizure activity is a common neurological emergency with a high mortality rate and, if left untreated, can lead to irreversible cerebral damage and systemic complications. Fast and effective first-line management is of paramount importance, particularly in the at-home management of seizures where drug...
Preprint
Full-text available
Background: Vestibular syndrome is often accompanied by nausea. Drugs currently approved for its treatment have been developed to stop vomiting but not nausea. The efficacy of 5‑HT3 receptor antagonists to reduce nausea has been described for chemotherapy, but not for nausea secondary to vestibular disorders. Methods: Sixteen dogs with vestibular s...
Article
Full-text available
Background Although the use of clinical reasoning has been evaluated for several neurological presentations, this approach has not yet been investigated for dogs with vestibular syndrome. Methods Two hundred and thirty‐nine dogs presenting with vestibular syndrome were included in this retrospective study. Univariate analysis of variables (clini...
Preprint
Status epilepticus (SE) or prolonged epileptic seizure activity is a common neurological emergency with a high mortality rate and, if left untreated, can lead to irreversible cerebral damage and systemic complications. Fast and effective first-line management is of paramount importance, particularly in the at-home management of seizures where drug...
Article
Full-text available
C-type natriuretic peptide (CNP) is the major natriuretic peptide of the central nervous system and acts via its selective guanylyl cyclase-B (GC-B) receptor to regulate cGMP production in neurons, astrocytes and endothelial cells. CNP is implicated in the regulation of neurogenesis, axonal bifurcation, as well as learning and memory. Several neuro...
Article
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Citation: Mirczuk, S.M.; Scudder, C.J.; Read, J.E.; Crossley, V.J.; Regan, J.T.; Richardson, K.M.; Simbi, B.; McArdle, C.A.; Church, D.B.; Fenn, J.; et al. Natriuretic Peptide Expression and Function in GH3 Somatolactotropes and Feline Somatotrope Pituitary Tumours. Int.
Article
Full-text available
Background: Poor medication compliance by human epilepsy patients is one of the leading causes of treatment failure and increased seizure frequency. The aim of this cross-sectional study was to analyse owner compliance in pharmacological treatment of canine idiopathic epilepsy and to identify factors associated with poor compliance. Methods: The...