Characterising the gut microbiome of stranded harbour seals (Phoca vitulina) in rehabilitation.

Animal rehabilitation centres provide a unique opportunity to study the microbiome of wild animals because subjects will be handled for their treatment and can therefore be sampled longitudinally. However, rehabilitation may have unintended consequences on the animals' microbiome because of a less varied and suboptimal diet, possible medical treatment and exposure to a different environment and human handlers. Our study describes the gut microbiome of two large seal cohorts, 50 pups (0-30 days old at arrival) and 23 weaners (more than 60 days old at arrival) of stranded harbour seals admitted for rehabilitation at the Sealcentre Pieterburen in the Netherlands, and the effect of rehabilitation on it. Faecal samples were collected from all seals at arrival, two times during rehabilitation and before release. Only seals that did not receive antimicrobial treatment were included in the study. The average time in rehabilitation was 95 days for the pups and 63 days for the weaners. We observed that during rehabilitation, there was an increase in the relative abundance of some of the Campylobacterota spp and Actinobacteriota spp. The alpha diversity of the pups' microbiome increased significantly during their rehabilitation (p-value <0.05), while there were no significant changes in alpha diversity over time for weaners. We hypothesize that aging is the main reason for the observed changes in the pups' microbiome. At release, the sex of a seal pup was significantly associated with the microbiome's alpha (i.e., Shannon diversity was higher for male pups, p-value <0.001) and beta diversity (p-value 0.001). For weaners, variation in the microbiome composition (beta diversity) at release was partly explained by sex and age of the seal (p-values 0.002 and 0.003 respectively). We mainly observed variables known to change the gut microbiome composition (e.g., age and sex) and conclude that rehabilitation in itself had only minor effects on the gut microbiome of seal pups and seal weaners.

Highly pathogenic avian influenza A virus (HPAIV) H5N1 infection in two European grey seals (Halichoerus grypus) with encephalitis.

ABSTRACTRecent reports documenting sporadic infections in carnivorous mammals worldwide with highly pathogenic avian influenza virus (HPAIV) H5N1 clade 2.3.4.4b have raised concerns about the potential risk of adaptation to sustained transmission in mammals, including humans. We report H5N1 clade 2.3.4.4b infection of two grey seals (Halichoerus grypus) from coastal waters of The Netherlands and Germany in December 2022 and February 2023, respectively. Histological and immunohistochemical investigations showed in both animals a non-suppurative and necrotising encephalitis with viral antigen restricted to the neuroparenchyma. Whole genome sequencing showed the presence of HPAIV H5N1 clade 2.3.4.4b strains in brain tissue, which were closely related to sympatric avian influenza viruses. Viral RNA was also detected in the lung of the seal from Germany by real-time quantitative PCR. No other organs tested positive. The mammalian adaptation PB2-E627K mutation was identified in approximately 40% of the virus population present in the brain tissue of the German seal. Retrospective screening for nucleoprotein-specific antibodies, of sera collected from 251 seals sampled in this region from 2020 to 2023, did not show evidence of influenza A virus-specific antibodies. Similarly, screening by reverse transcription PCR of tissues of 101 seals that had died along the Dutch coast in the period 2020-2021, did not show evidence of influenza virus infection. Collectively, these results indicate that individual seals are sporadically infected with HPAIV-H5N1 clade 2.3.4.4b, resulting in an encephalitis in the absence of a systemic infection, and with no evidence thus far of onward spread between seals.

Caracterización clínico-quirúrgica de pacientes con pancreatitis aguda, Guantánamo 2016-2020

Introducción: La pancreatitis aguda es una problemática de salud médico-quirúrgica a escala mundial. En Guantánamo, no se encuentran estudios sobre las características clínicas y quirúrgicas de pacientes con esta afección. Objetivo: Caracterizar a pacientes con pancreatitis aguda atendidos en el Hospital General Docente "Dr. Agostinho Neto", provincia Guantánamo, Cuba, durante los años 2016-2020 desde una perspectiva clínica y quirúrgica. Método: Se realizó un estudio descriptivo, retrospectivo y longitudinal en 86 pacientes egresados de dicho hospital, donde fueron analizadas las variables: edad, sexo, clasificación, etiología, diagnóstico, tratamiento, complicaciones de la pancreatitis, estadía evolución y otras. Se asumieron los resultados al momento del ingreso de: glucemia, calcemia, amilasemia, ultrasonido diagnóstico abdominal y tomografía axial computadorizada de abdomen. Resultados: La edad media del grupo fue de 53,8 ± 18,6 años. Fue más frecuente la pancreatitis aguda en fase temprana (70,9 %), la edematosa intersticial (90,7 %), tipo grave (51,2 %) y la biliar (32,6 %). El dolor abdominal (100 %) fue el principal síntoma. El 77,9 % presentó hiperamilasemia. El 77,4 % y el 73,3 % mostró anormalidades en el ultrasonido y en la tomografía de páncreas, respectivamente. El tratamiento quirúrgico más realizado fue la necrosectomía y abdomen cerrado (60,4 %). El 100 % presentó alguna complicación. La estadía fue de 11,0 ± 7,2 días. Conclusiones: La pancreatitis aguda impacta como problemática de salud, de modo más común en su forma grave, determinada por litiasis en la vía biliar, y por la elevada frecuencia de complicaciones.

Introduction: Acute pancreatitis is a medical and surgical health problem at worldwide. In Guantanamo, there is not studies found related to patients with the over mentioned clinical and surgical characteristics. Objective: Characterization, from a clinical and surgical perspective, of patients with acute pancreatitis attended at the Hospital General Docente "Dr. Agostinho Neto", Guantánamo province, Cuba, throughout 2016 to 2020. Method: A descriptive, retrospective and longitudinal study was carried out in 86 discharged patients. Variables used were as follow: age, sex, classification, etiology, diagnostic, treatment, pancreatitis complications, stay, evolution and, others. The clinical outcomes assumed at admission time were as follow: glycemia, calcaemia, amylasemia, abdominal ultrasound diagnosis and abdominal computed tomography. Results: The mean age of the group studied was 53.8 ± 18.6 years. Early stage acute pancreatitis (70.9 %), interstitial edematous (90.7 %), severe pancreatitis (51.2 %) and, biliary pancreatitis (32.6 %) were more frequent. Abdominal pain in the patients studied (100 %) was the main symptom. Hyperamylasemia was present in 77.9 %. The 77.4 % of the patients showed abnormalities in ultrasound and 73.3 % at the Computed tomography of the pancreas. The most frequently performed surgical treatment was necrosectomy and closed abdomen (60.4 %). The 100 % of the patients admitted presented some complications. The term of stay in admission was 11.0±7.2 days. Conclusions: Acute pancreatitis as a health problem commonly arises in its severe form, characterized by the presence of lithiasis in the biliary tract and the high frequency of complications.

Introdução: A pancreatite aguda é um problema de saúde médico-cirúrgico em todo o mundo. Em Guantánamo, não há estudos sobre as características clínicas e cirúrgicas dos pacientes com essa condição. Objetivo: Caracterizar os pacientes com pancreatite aguda atendidos no Hospital General Docente "Dr. Agostinho Neto", província de Guantánamo, Cuba, durante os anos 2016-2020 do ponto de vista clínico e cirúrgico. Método: Foi realizado um estudo descritivo, retrospectivo e longitudinal em 86 pacientes egressos do referido hospital, onde foram analisadas as variáveis: idade, sexo, classificação, etiologia, diagnóstico, tratamento, complicações da pancreatite, tempo de internação e outros. Os resultados no momento da admissão foram assumidos: glicemia, calcemia, amilase, ultrassonografia abdominal diagnóstica e tomografia axial computadorizada de abdome. Resultados: A média de idade do grupo foi de 53,8 ± 18,6 anos. Pancreatite aguda na fase inicial (70,9%), edema intersticial (90,7%), grave (51,2%) e biliar (32,6%) foram mais frequentes. Dor abdominal (100%) foi o principal sintoma. 77,9% apresentaram hiperamilasemia. 77,4% e 73,3% apresentaram anormalidades na ultrassonografia e tomografia pancreática, respectivamente. O tratamento cirúrgico mais realizado foi necrosectomia e abdome fechado (60,4%). 100% apresentaram alguma complicação. A permanência foi de 11,0 ± 7,2 dias. Conclusões: A pancreatite aguda impacta como problema de saúde, mais comumente em sua forma grave, determinada pela litíase no ducto biliar e pela alta frequência de complicações.

Novel 3D in situ visualization of seal heartworm (Acanthocheilonema spirocauda) larvae in the seal louse (Echinophthirius horridus) by X-ray microCT.

The seal heartworm Acanthocheilonema spirocauda (Nematoda: Onchocercidae) parasitizes the heart and pulmonary arteries of various phocid seals of the Northern Hemisphere. Over many decades, potential vectors of this parasite have been discussed, and to this date, the life cycle is not fully known. The seal louse Echinophthirius horridus (Anoplura: Echinophthiriidae) is an obligatory, permanent and haematophagous ectoparasite of phocids that has been hypothesized to function as obligate intermediate host for A. spirocauda. We examined 11 adult E. horridus specimens collected from stranded harbour seals (Phoca vitulina) in rehabilitation at the Sealcentre Pieterburen by X-ray microCT imaging, aiming to illustrate larval A. spirocauda infection sites in situ. In three of these specimens, thread-like larvae were detected in insect organs. Detailed imaging of the most infected louse revealed a total of 54 A. spirocauda larvae located either in fat bodies or the haemocoel. Histological analysis of the same specimen illustrated nematode cross-sections, confirming X-ray microCT data. The current data strongly suggest that E. horridus is a natural intermediate host for A. spirocauda. Moreover, we demonstrate the potential of X-ray microCT-based imaging as a non-destructive method to analyze host-parasite interactions, especially in the neglected field of marine mammal parasitology.

Prevalence of metabolic syndrome and related factors in a large sample of antipsychotic naïve patients with first-episode psychosis: Baseline results from the PAFIP cohort.

BACKGROUND: Few investigations have been carried out on metabolic syndrome in antipsychotic- naïve patients with schizophrenia. METHODS: Our primary objective was to compare the prevalence of Metabolic Syndrome (MetS), as defined by the National Cholesterol Education Program, Adult Treatment Panel III in 2001 (NCEP-ATP III), between a Spanish cohort of 303 drug-naïve patients with a first episode of psychosis (FEP) without any previous cardiovascular condition, and 153 healthy individuals. RESULTS: Participants included 303 patients with FEP (M:F 53:46) and 153 control subjects (M:F 56:43). The mean and standard deviation ages were 31(9.38) and 29 (7.57) years in the study and control groups respectively (F = 4.09; p = 0.93). We found that the prevalence of MetS in drug-naïve patients with FEP (5.6 %) was similar to the prevalence of MetS in age-sex matched controls (5.12 %). However, 60.7 % of patients with FEP met at least one of the five MetS components, while among the control subjects only 36.5 % met at least one component. Additionally, we found that other factors not included among the operational definition of MetS, but still important in cardiovascular risk, were also altered. CONCLUSION: FEP patients have a greater risk of presenting at least one altered MetS component than healthy controls which could indicate the need of development of screening methods detecting cardiovascular risk. Likewise, gender differences in metabolic components such as waist circumference, which is a predictor of cardiovascular events have been found. Similarly, research should focus on metabolic risk predictors that include not only MetS, but also specific parameters for the early psychosis population.

Vocal tract allometry in a mammalian vocal learner.

Acoustic allometry occurs when features of animal vocalisations can be predicted from body size measurements. Despite this being considered the norm, allometry sometimes breaks, resulting in species sounding smaller or larger than expected for their size. A recent hypothesis suggests that allometry-breaking mammals cluster into two groups: those with anatomical adaptations to their vocal tracts and those capable of learning new sounds (vocal learners). Here, we tested which mechanism is used to escape from acoustic allometry by probing vocal tract allometry in a proven mammalian vocal learner, the harbour seal (Phoca vitulina). We tested whether vocal tract structures and body size scale allometrically in 68 young individuals. We found that both body length and body mass accurately predict vocal tract length and one tracheal dimension. Independently, body length predicts vocal fold length while body mass predicts a second tracheal dimension. All vocal tract measures are larger in weaners than in pups and some structures are sexually dimorphic within age classes. We conclude that harbour seals do comply with anatomical allometric constraints. However, allometry between body size and vocal fold length seems to emerge after puppyhood, suggesting that ontogeny may modulate the anatomy-learning distinction previously hypothesised as clear cut. We suggest that seals, and perhaps other species producing signals that deviate from those expected from their vocal tract dimensions, may break allometry without morphological adaptations. In seals, and potentially other vocal learning mammals, advanced neural control over vocal organs may be the main mechanism for breaking acoustic allometry.

Trauma and stressor-related disorders among health care workers during COVID-19 pandemic and the role of the gender: A prospective longitudinal survey.

INTRODUCTION: Health-care Workers (HCW) are facing a critical situation caused by Coronavirus Disease 2019 (COVID-19) which could impact on their mental health status. In addition, HCW women have been identified as a group at high-risk of developing psychological distress, although no previous longitudinal studies have explored this issue in a sample of HCW. AIMS: The main aim of the study was to observe the temporal pattern of the stress reactions among HCW as well as to explore its potential predictors of poor outcome. Moreover, we analyzed possible gender differences in stress reaction responses. METHODS: One thousand for hundred and thirty-two HCW responded an online survey including sociodemographic, clinical, and psychometric tests in May 2020 while 251 HCW answered in November 2020. Bivariate and multivariate analyses as well as repeated measures analyses were used to achieve the aims of the study. RESULTS: The proportion of HCW who fulfilled Acute Stress Disorder criteria did not change over the follow-up period, although we observed a significant improvement in stress reactions responses among HCW. Proximal factors were the most salient predictors of traumatic reactions. Repeated analyses revealed significant gender differences in acute stress reactions. In addition, women showed significantly greater improvement than men in re-experiencing the traumatic event and hyperarousal dimensions. CONCLUSIONS: Monitoring of working conditions as well as emotional reactions in HCW facing major disasters should be carried out to prevent the development of peritraumatic stress reactions. In addition, HCW women are characterized by a different pattern of progression in stress responses.

Drug-drug Interactions between COVID-19 Treatments and Antidepressants, Mood Stabilizers/Anticonvulsants, and Benzodiazepines: Integrated Evidence from 3 Databases.

INTRODUCTION: The SARS-CoV-2 pandemic with psychiatric comorbidities leads to a scenario in which the use of psychotropic drugs may be required. This requires the support of evidence-based medicine to take into account possible interactions between antidepressants, mood stabilizers, benzodiazepines, and coronavirus infection treatments. METHODS: Three databases were consulted: (a) Lexicomp Drug Interactions, (b) Micromedex Solutions Drugs Interactions, (c)Liverpool Drug Interaction Group for COVID-19 therapies. The CredibleMeds QTDrugs List was also queried. Hydroxychloroquine, chloroquine, azithromycin, lopinavir-ritonavir, remdesivir, favipiravir, tocilizumab, baricitinib, anakinra, and dexamethasone - drugs used for SARS-CoV-2 - were analyzed, and consensus recommendations are made. RESULTS: The potential interactions of agomelatine, desvenlafaxine, duloxetine, milnacipran, and vortioxetine with COVID-19 treatments shall be considered less risky. Antidepressant interactions with hydroxychloroquine, chloroquine, and azithromycin enhance the risk of QT prolongation, and ECG monitoring is advised for most antidepressants. Antidepressants with lopinavir/ritonavir involve multiple CYP enzyme interactions (except with milnacipran). Gabapentin, oxcarbazepine, pregabalin, topiramate, and zonisamide are safe treatment options that have no significant interactions with COVID-19 treatments. Lithium is contraindicated with hydroxychloroquine, chloroquine, and azithromycin. Precaution should be taken in using valproic acid with lopinavir-ritonavir. The use of benzodiazepines does not present a risk of drug interaction with COVID-19 treatments, except lopinavir/ritonavir. CONCLUSIONS: Clinicians prescribing antidepressants, mood stabilizers/anticonvulsants, and benzodiazepines, should be aware of the probable risk of drug-drug interaction with COVID-19 medications and may benefit from heeding these recommendations for use to ensure patient safety.

Neuroanatomy of the grey seal brain: bringing pinnipeds into the neurobiological study of vocal learning.

Comparative animal studies of complex behavioural traits, and their neurobiological underpinnings, can increase our understanding of their evolution, including in humans. Vocal learning, a potential precursor to human speech, is one such trait. Mammalian vocal learning is under-studied: most research has either focused on vocal learning in songbirds or its absence in non-human primates. Here, we focus on a highly promising model species for the neurobiology of vocal learning: grey seals (Halichoerus grypus). We provide a neuroanatomical atlas (based on dissected brain slices and magnetic resonance images), a labelled MRI template, a three-dimensional model with volumetric measurements of brain regions, and histological cortical stainings. Four main features of the grey seal brain stand out: (i) it is relatively big and highly convoluted; (ii) it hosts a relatively large temporal lobe and cerebellum; (iii) the cortex is similar to that of humans in thickness and shows the expected six-layered mammalian structure; (iv) there is expression of FoxP2 present in deeper layers of the cortex; FoxP2 is a gene involved in motor learning, vocal learning, and spoken language. Our results could facilitate future studies targeting the neural and genetic underpinnings of mammalian vocal learning, thus bridging the research gap from songbirds to humans and non-human primates. Our findings are relevant not only to vocal learning research but also to the study of mammalian neurobiology and cognition more in general. This article is part of the theme issue 'Vocal learning in animals and humans'.

The seal louse (Echinophthirius horridus) in the Dutch Wadden Sea: investigation of vector-borne pathogens.

BACKGROUND: Belonging to the anopluran family Echinophthiriidae, Echinophthirius horridus, the seal louse, has been reported to parasitise a broad range of representatives of phocid seals. So far, only a few studies have focused on the vector function of echinophthiriid lice, and knowledge about their role in pathogen transmission is still scarce. The current study aims to investigate the possible vector role of E. horridus parasitising seals in the Dutch Wadden Sea. METHODS: E. horridus seal lice were collected from 54 harbour seals (Phoca vitulina) and one grey seal (Halichoerus grypus) during their rehabilitation period at the Sealcentre Pieterburen, The Netherlands. DNA was extracted from pooled seal lice of individual seals for molecular detection of the seal heartworm Acanthocheilonema spirocauda, the rickettsial intracellular bacterium Anaplasma phagocytophilum, and the cell wall-less bacteria Mycoplasma spp. using PCR assays. RESULTS: Seal lice from 35% of the harbour seals (19/54) and from the grey seal proved positive for A. spirocauda. The seal heartworm was molecularly characterised and phylogenetically analysed (rDNA, cox1). A nested PCR was developed for the cox1 gene to detect A. spirocauda stages in seal lice. A. phagocytophilum and a Mycoplasma species previously identified from a patient with disseminated 'seal finger' mycoplasmosis were detected for the first time, to our knowledge, in seal lice. CONCLUSIONS: Our findings support the potential vector role of seal lice in the transmission of A. spirocauda and reveal new insights into the spectrum of pathogens occurring in seal lice. Studies on vector competence of E. horridus, especially for bacterial pathogens, are essentially needed in the future as these pathogens might have detrimental effects on the health of seal populations. Furthermore, studies on the vector role of different echinophthiriid species infecting a wide range of pinniped hosts should be conducted to extend the knowledge of vector-borne pathogens.

Drug-drug interactions between COVID-19 treatments and antipsychotics drugs: integrated evidence from 4 databases and a systematic review.

RATIONALE: Management of anxiety, delirium, and agitation cannot be neglected in coronavirus disease (COVID-19). Antipsychotics are usually used for the pharmacological management of delirium, and confusion and behavioral disturbances. The concurrent use of treatments for COVID-19 and antipsychotics should consider eventual drug-drug interactions OBJECTIVE: To systematically review evidence-based available on drug-drug interactions between COVID-19 treatments and antipsychotics. EVIDENCE REVIEW: Three databases were consulted: Lexicomp® Drug Interactions, Micromedex® Solutions Drugs Interactions, and Liverpool© Drug Interaction Group for COVID-19 therapies. To acquire more information on QT prolongation and Torsade de Pointes (TdP), the CredibleMeds® QTDrugs List was searched. The authors made a recommendation agreed to by consensus. Additionally, a systematic review of drug-drug interactions between antipsychotics and COVID-19 treatment was conducted. RESULTS: The main interactions between COVID-19 drugs and antipsychotics are the risk of QT-prolongation and TdP, and cytochromes P450 interactions. Remdesivir, baricinitib, and anakinra can be used concomitantly with antipsychotics without risk of drug-drug interaction (except for hematological risk with clozapine and baricinitib). Favipiravir only needs caution with chlorpromazine and quetiapine. Tocilizumab is rather safe to use in combination with antipsychotics. The most demanding COVID-19 treatments for coadministration with antipsychotics are chloroquine, hydroxychloroquine, azithromycin, and lopinavir/ritonavir because of the risk of QT prolongation and TdP and cytochromes interactions. The systematic review provides highly probable drug interaction between lopinavir/ritonavir plus quetiapine and ritonavir/indinavir plus risperidone. CONCLUSIONS: Clinicians prescribing antipsychotics should be aware of the likely risk of drug-drug interaction with COVID-19 medication and may benefit from taking into account present recommendations of use to preserve patient safety.

After the bite: bacterial transmission from grey seals (Halichoerus grypus) to harbour porpoises (Phocoena phocoena).

Recent population growth of the harbour porpoise (Phocoena phocoena), grey seal (Halichoerus grypus) and common seal (Phoca vitulina) in the North Sea has increased potential interaction between these species. Grey seals are known to attack harbour porpoises. Some harbour porpoises survive initially, but succumb eventually, often showing severely infected skin lesions. Bacteria transferred from the grey seal oral cavity may be involved in these infections and eventual death of the animal. In humans, seal bites are known to cause severe infections. In this study, a 16S rRNA-based microbiome sequencing approach is used to identify the oral bacterial diversity in harbour porpoises, grey seals and common seals; detect the potential transfer of bacteria from grey seals to harbour porpoises by biting and provide insights in the bacteria with zoonotic potential present in the seal oral cavity. ß-diversity analysis showed that 12.9% (4/31) of the harbour porpoise skin lesion microbiomes resembled seal oral microbiomes, while most of the other skin lesion microbiomes also showed seal-associated bacterial species, including potential pathogens. In conclusion, this study shows that bacterial transmission from grey seals to harbour porpoises by biting is highly likely and that seal oral cavities harbour many bacterial pathogens with zoonotic potential.

HEMATOLOGY AND SERUM BIOCHEMISTRY OF HARBOR SEAL (PHOCA VITULINA) PUPS AFTER REHABILITATION IN THE NETHERLANDS.

Hematology and serum biochemistry profiles are used to evaluate the health status of animals ongoing rehabilitation. The aim of this project was to develop blood and biochemistry ranges for harbor seal pups (Phoca vitulina) after rehabilitation; thus, 22 different blood parameters in 60 animals were tested before release. The second goal was to test for differences due to sex, stranding location, body condition at admission, and presence or absence of umbilical cord. The alanine aminotransferase, ALT (or glutamate pyruvate transaminase, GPT), (ALT-GPT) differed significantly (P bq = 0.00851) between sexes. Lower leukocyte counts and higher liver enzyme values were the most remarkable findings when comparing the results of this study to other published data. This is the first study to report blood reference ranges for harbor seal pups in the Dutch Wadden Sea after rehabilitation.

RETROSPECTIVE STUDY OF SURGICAL TREATMENT OF REFRACTIVE OSTEOMYELITIS AND INFECTIOUS ARTHRITIS IN THE FLIPPERS OF SEALS IN THE NETHERLANDS.

Amputation surgery in pinniped rehabilitation centers is a feasible procedure when animals are presented with open fractures, osteomyelitis, and/or infectious arthritis of the flippers that appear to be refractory to medical treatment. From 2011 to 2017, the Sealcentre Pieterburen in The Netherlands admitted 3,775 seals for rehabilitation. Of these, 37 individuals presented clinical and radiologic signs of bone abnormalities indicative of osteomyelitis or infectious arthritis refractory to medical treatment. Seven cases resulted in euthanasia, and 30 cases underwent amputation surgery. The surgical procedure involved amputation of part of a flipper (24; two animals twice) or of a complete flipper (eight). All procedures were done under general anesthesia except one that was performed with local anesthesia, and all 30 animals were released. In two cases, the osteomyelitis presented with the rare Totenlade phenomenon, a sequestrum surrounded by new periosteal bone formation. The purpose of this retrospective study was to evaluate the outcome of the operative treatment of osteomyelitis and infectious arthritis in the flippers of harbor (Phoca vitulina) and grey seals (Halichoerus grypus) during this 6-yr period.

Ontogeny of vocal rhythms in harbor seal pups: an exploratory study.

Puppyhood is a very active social and vocal period in a harbor seal's life Phoca vitulina. An important feature of vocalizations is their temporal and rhythmic structure, and understanding vocal timing and rhythms in harbor seals is critical to a cross-species hypothesis in evolutionary neuroscience that links vocal learning, rhythm perception, and synchronization. This study utilized analytical techniques that may best capture rhythmic structure in pup vocalizations with the goal of examining whether (1) harbor seal pups show rhythmic structure in their calls and (2) rhythms evolve over time. Calls of 3 wild-born seal pups were recorded daily over the course of 1-3 weeks; 3 temporal features were analyzed using 3 complementary techniques. We identified temporal and rhythmic structure in pup calls across different time windows. The calls of harbor seal pups exhibit some degree of temporal and rhythmic organization, which evolves over puppyhood and resembles that of other species' interactive communication. We suggest next steps for investigating call structure in harbor seal pups and propose comparative hypotheses to test in other pinniped species.

Association of Batai Virus Infection and Encephalitis in Harbor Seals, Germany, 2016.

We isolated Batai virus from the brain of a euthanized, 26-year-old, captive harbor seal with meningoencephalomyelitis in Germany. We provide evidence that this orthobunyavirus can naturally infect the central nervous system of a mammal. The full-genome sequence showed differences from a previously reported virus isolate from a mosquito in Germany.

Campylobacter blaseri sp. nov., isolated from common seals (Phoca vitulina).

During a study to assess the faecal microbiome of common seals (Phoca vitulina) in a Dutch seal rehabilitation centre, 16S rRNA gene sequences of an unknown Campylobacter taxon were identified. Campylobacter isolates, which differed from the established Campylobacter taxa, were cultured and their taxonomic position was determined by a polyphasic study based on ten isolates. The isolates were characterized by 16S rRNA and atpA gene sequence analyses and by conventional phenotypic testing. Based on the whole genome sequences, the average nucleotide identity and core genome phylogeny were determined. The isolates formed a separate phylogenetic clade, divergent from all other Campylobacter taxa and most closely related to Campylobacter corcagiensis, Campylobacter geochelonis and Campylobacter ureolyticus. The isolates can be distinguished phenotypically from all other Campylobacter taxa based on their lack of motility, growth at 25 °C and growth on MacConkey agar. This study shows that these isolates represent a novel species within the genus Campylobacter, for which the name Campylobacter blaseri sp. nov. is proposed. The type strain for this novel species is 17S00004-5T (=LMG 30333T=CCUG 71276T).

How small could a pup sound? The physical bases of signaling body size in harbor seals.

Vocal communication is a crucial aspect of animal behavior. The mechanism which most mammals use to vocalize relies on three anatomical components. First, air overpressure is generated inside the lower vocal tract. Second, as the airstream goes through the glottis, sound is produced via vocal fold vibration. Third, this sound is further filtered by the geometry and length of the upper vocal tract. Evidence from mammalian anatomy and bioacoustics suggests that some of these three components may covary with an animal's body size. The framework provided by acoustic allometry suggests that, because vocal tract length (VTL) is more strongly constrained by the growth of the body than vocal fold length (VFL), VTL generates more reliable acoustic cues to an animal's size. This hypothesis is often tested acoustically but rarely anatomically, especially in pinnipeds. Here, we test the anatomical bases of the acoustic allometry hypothesis in harbor seal pups Phoca vitulina. We dissected and measured vocal tract, vocal folds, and other anatomical features of 15 harbor seals post-mortem. We found that, while VTL correlates with body size, VFL does not. This suggests that, while body growth puts anatomical constraints on how vocalizations are filtered by harbor seals' vocal tract, no such constraints appear to exist on vocal folds, at least during puppyhood. It is particularly interesting to find anatomical constraints on harbor seals' vocal tracts, the same anatomical region partially enabling pups to produce individually distinctive vocalizations.

Lungworm seroprevalence in free-ranging harbour seals and molecular characterisation of marine mammal MSP.

Harbour seals (Phoca vitulina) are frequently infected with the lungworms Otostrongylus circumlitus and Parafilaroides gymnurus. The infection is often accompanied by secondary bacterial infections and can cause severe bronchopneumonia and even death in affected animals. Hitherto, the detection of lungworm infections was based on post mortem investigations from animals collected within stranding networks and a valid detection method for live free-ranging harbour seals was not available. Recently, an ELISA was developed for detecting lungworm antibodies in harbour seal serum, using major sperm protein (MSP) of the bovine lungworm, Dictyocaulus viviparus as recombinant diagnostic antigen. To determine lungworm seroprevalence in free-ranging harbour seals, serum was taken from four different seal age groups (n = 313) resulting in an overall prevalence of 17.9% (18.9% of males, 16.7% of females). 0.7% of harbour seals up to six weeks of age were seropositive, as were 89% of seals between six weeks and six months, 53.6% between six and 18 months and 24.2% of seals over 18 months of age. In the 18 months and over age group, seropositive animals showed statistically significant reductions in body weight (P = 0.003) and length (P < 0.001). Sera from lungworm infected harbour seals in rehabilitation (n = 6) revealed that duration of antibody persistence may be similar to that of lungworm infected cattle, but further studies are needed to confirm this. Phylogenetic analyses of MSP sequences of different marine and terrestrial mammal parasitic nematodes revealed that lungworm MSP of the genus Dictyocaulus (superfamily Trichostrongyloidea) is more closely related to metastrongylid marine mammal lungworms than to trichostrongylid nematodes of terrestrial hosts.