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Whale lice (Cyamidae; Amphipoda) are ectoparasitic crustaceans adapted to the marine environment with cetaceans as their host. There are few reports of cyamids occurring in odontocetes from the North Sea, and long-term studies are lacking. Marine mammal health was monitored along the German and Dutch coasts in the past decades, with extensive post mortem investigations conducted. The aim of this study was to analyse archived ectoparasite samples from stranded cetaceans from the North Sea (2010–2019), to determine species, prevalence and impact of ectoparasite infection. Ectoparasites were found on two cetacean species – harbour porpoises (Phocoena phocoena), as the most abundant cetacean species in the North Sea, and on a pilot whale (Globicephala melas), as a rare species here. Prevalence of ectoparasitic crustaceans in cetaceans was low: 7.6% in porpoises stranded in the Netherlands (n = 608) and 1.6% in porpoises stranded in Germany (n = 122). All whale lice infections were found on hosts with skin lesions characterised by ulcerations. Morphological investigations revealed characteristic differences between the cyamid species Isocyamus (I.) delphinii and I. deltobranchium identified. Isocyamus deltobranchium was determined in all infected harbour porpoises. I. delphinii was identified on only the pilot whale. Molecular analyses showed 88% similarity of mDNA COI sequences of I. delphinii with I. deltobranchium supporting them as separate species. Phylogenetic analyses of additional gene loci are required to fully assess the diversity and exchange of whale lice species between geographical regions as well as host specificity. Differing whale lice prevalences in porpoises stranded in the Netherlands and Germany could indicate a difference in severity of skin lesions between these areas. It should be further investigated if more inter- or intraspecific contact, e.g., due to a higher density of porpoises or contact with other cetaceans, or a poorer health status of porpoises in the southern North Sea could explain these differences. [Display omitted] • First long term study of ectoparasitic crustaceans on North Sea odontocetes. • Differences in prevalence in harbour porpoises between German and Dutch waters. • Two cyamid species identified using morphological and molecular traits. • associated to skin lesions in all investigated harbour porpoises and pilot whale. • I. deltobranchium and I. delphinii closely related. [ABSTRACT FROM AUTHOR]

Effective management of natural resources involves a multidisciplinary perspective to address complex issues in data poor-environments. With mobile species that do not conform to human-defined borders a cross-boundary approach is essential. There is a continuing concern of ecological sustainability of marine environments, which demands monitoring of ecosystem indicators. Such indicators are increasingly derived from monitoring sentinel species. Harbour porpoises ( Phocoena phocoena ) are included as indicator species in several national and international agreements. Increasing exposure to anthropogenic stressors may impact harbour porpoise populations. To investigate these risks, a better understanding of threats and their effect is required. This study aimed to identify current knowledge gaps, to predict future pressures or threats, and to define useful conservation indicators to facilitate future research on harbour porpoises in the North Sea, through expert elicitation gained in a two-round Delphi approach. The three most important knowledge gaps addressed were bycatch, population dynamics, and the cumulative effects of multiple stressors. Bycatch was predicted as the highest concern for porpoises in the next 20 years, followed by chemical and noise pollution, respectively. A list of essential indicators aiming to increase understanding of harbour porpoises’ health status was established and studying causes of death, distribution, abundance, habitat use and diet composition were scored as most relevant. These results should guide research focus and management objectives of harbour porpoise populations and the study design could be translated to serve managers in other geographical areas aiming to identify knowledge gaps and defining research priorities for other wildlife species. [ABSTRACT FROM AUTHOR]

30 sperm whales ( Physeter macrocephalus ) stranded along the coasts of the North Sea between January and February 2016. The gastro-intestinal tracts of 22 of the carcasses were investigated. Marine debris including netting, ropes, foils, packaging material and a part of a car were found in nine of the 22 individuals. Here we provide details about the findings and consequences for the animals. While none of the items was responsible for the death of the animal, the findings demonstrate the high level of exposure to marine debris and associated risks for large predators, such as the sperm whale. [ABSTRACT FROM AUTHOR]

Abstract: Clostridium perfringens is one of the major causes of intestinal disease in humans and animals. Its pathogenicity is contributed to by the production of a variety of toxins. In addition, predisposing environmental factors are important for the induction of C. perfringens-associated enteritis as shown by infection models. Environmental contamination, gastric and intestinal pH, intestinal microflora, nutrition, concurrent infections, and medical interventions may influence the intestinal colonization, growth, and toxin production by C. perfringens. Prevention of C. perfringens-associated enteritis may be mediated by the use of feed additives like probiotics, prebiotics, organic acids, essential oils, bacteriophages, lysozymes, bacteriocins, and antimicrobial peptides. Here we summarize and discuss published data on the influence of different environmental predisposing factors and preventive measures. Further research should focus on feed composition and feed additives in order to prevent C. perfringens-associated enteritis. [Copyright &y& Elsevier]

The virulence of Clostridium perfringens, a bacterium causing enteritis and enterotoxaemia in domestic and wild animals and humans, results largely from its ability to produce toxins. In 1997, an unknown toxin of C. perfringens, the β2-toxin, and its encoding gene cpb2 were described. Since that time numerous studies have been published dealing with a possible association of cpb2-harbouring strains of C. perfringens and the occurrence of enteric disease in domestic and wild animals and humans. This article offers an overview of the current literature on the spread and pathological significance of cph2-harbouring C perfringens. Unambiguous conclusions on the prevalence of cpb2 and the contribution of β2-toxin to the disease cannot be drawn from existing studies but in some animal species a strong correlation between the presence of cpb2-harbouring C. perfringens, the β2-toxin and enteric disease has been reported. [ABSTRACT FROM AUTHOR]

Respiratory viral infections are among the major causes of disease in poultry. While viral dual infections are known to occur, viral interference in chicken airways is mechanistically hardly understood. The effects of infectious bronchitis virus (IBV) infection on tissue morphology, sialic acid (sia) expression and susceptibility of the chicken trachea for superinfection with IBV or avian influenza virus (AIV) were studied. In vivo , tracheal epithelium of chickens infected with IBV QX showed marked inflammatory cell infiltration and loss of cilia and goblet cells five days post inoculation. Plant lectin staining indicated that sialic acids redistributed from the apical membrane of the ciliated epithelium and the goblet cell cytoplasm to the basement membrane region of the epithelium. After administration of recombinant viral attachment proteins to slides of infected tissue, retained binding of AIV hemagglutinin, absence of binding of the receptor binding domain (RBD) of IBV M41 and partial reduction of IBV QX RBD were observed. Adult chicken trachea rings were used as ex vivo model to study the effects of IBV QX-induced pathological changes and receptor redistribution on secondary viral infection. AIV H9N2 infection after primary IBV infection was delayed; however, final viral loads reached similar levels as in previously uninfected trachea rings. In contrast, IBV M41 superinfection resulted in 1000-fold lower viral titers over the course of 48 h. In conclusion, epithelial changes in the chicken trachea after viral infection coincide with redistribution and likely specific downregulation of viral receptors, with the extend of subsequent viral interference dependent on viral species. • Infectious bronchitis virus (IBV) induces sialic acid redistribution in the trachea. • Previous IBV infection changes influenza virus and IBV attachment protein binding. • Adult chicken tracheal organ cultures (TOCs) provide a suitable ex vivo model. • Primary IBV infection hampers influenza virus less than secondary IBV infection. [ABSTRACT FROM AUTHOR]

Along the Dutch shores hundreds of harbour porpoises Phocoena phocoena are stranded each year. A recurrent phenomenon in the Netherlands is a surge of strandings in late winter and early spring of severely mutilated porpoises, that are mostly in good nutritional body condition (thick blubber layer). These mutilated porpoises have parts of the skin and blubber, and sometimes of the muscle tissue missing. By reviewing photographs of stranded animals taken at the stranding sites as well as autopsy results we found 273 mutilated animals from 2005 to 2012. Mutilations could be classified into several categories, but wounds had been mostly inflicted to the sides of these animals, in a zigzag fashion, or to the throat/cheek region. The stomach contents of 31 zigzags, 12 throats/cheeks and 31 control animals that were not mutilated, from the same age and blubber thickness categories were compared; all these animals had stranded between December and April, 2006–2012. The diet of individuals with zigzag lesions to their sides consisted for a large part of gobies, while animals that had wounds at the throat/cheek had been feeding predominately on clupeids. In comparison, animals without mutilations had a more varied diet, including gobies and clupeids, but also a large proportion of sandeels and gadoids. The finding that the type of mutilation corresponds to a certain diet suggests that porpoises that were feeding on different prey, or in different micro-habitats, were hit in different ways. Animals feeding at the sea floor (on gobies) apparently run a risk of being hit from the side, while animals supposedly feeding higher in the water column (on schooling clupeids), were predominantly hit from below, in the throat region. The wider variation in the diets of non-mutilated porpoises is suggestive of them using a larger variety of micro-habitats. [ABSTRACT FROM AUTHOR]

• Influenza D has a wide host tropism in both domestic and wild animals despite a very specific receptor preference. • Differences in tissue tropism exist between the two major influenza D clades in water buffalo, Asian elephant, and hedgehog. • Despite positive serosurveillance data, wild Suidae and Cervidea do not express influenza D receptors. • Influenza D has potential to spread from domesticated animals to wildlife and vice versa. The influenza D virus (IDV) uses a trimeric hemagglutinin-esterase fusion protein (HEF) for attachment to 9-O-acetylated sialic acid receptors on the cell surface of host species. So far research has revealed that farm animals such as cattle, domestic pigs, goats, sheep and horses contain the necessary receptors on the epithelial surface of the respiratory tract to accommodate binding of the IDV HEF protein of both worldwide clades D/Oklahoma (D/OK) and D/Oklahoma/660 (D/660). More recently, seroprevalence studies have identified IDV-seropositive wildlife such as wild boar, deer, dromedaries, and small ruminants. However, no research has thus far been conducted in wildlife to reveal the distribution of acetylated sialic acid receptors that accommodate binding of IDV. Using our previously developed tissue microarray (TMA) system, we developed TMAs containing respiratory tissues of various wild and domestic species including wild boar, deer, dromedary, springbok, water buffalo, tiger, hedgehog, and Asian elephant. Protein histochemical staining of these TMAs with HEF proteins showed no receptor binding for wild Suidae, Cervidae and tiger. However, receptors were present in dromedary, springbok, water buffalo, Asian elephant, and hedgehog. In contrast to previously tested farm animals, a difference in host tropism was observed between the D/OK and D/660 clade HEF proteins in Asian elephant, and water buffalo. These results show that IDV can attach to the respiratory tract of wildlife which might facilitate transmission of IDV between wildlife and domestic animals. [ABSTRACT FROM AUTHOR]

Abstract: Pneumoviruses such as pneumonia virus of mice (PVM), bovine respiratory syncytial virus (bRSV) or human (h)RSV are closely related pneumoviruses that cause severe respiratory disease in their respective hosts. It is well-known that T-cell responses are essential in pneumovirus clearance, but pneumovirus-specific T-cell responses also are important mediators of severe immunopathology. In this study we determined whether memory- or pre-existing, transferred virus-specific CD8+ T-cells provide protection against PVM-induced disease. We show that during infection with a sublethal dose of PVM, both natural killer (NK) cells and CD8+ T-cells expand relatively late. Induction of CD8+ T-cell memory against a single CD8+ T-cell epitope, by dendritic cell (DC)-peptide immunization, leads to partial protection against PVM challenge and prevents Th2 differentiation of PVM-induced CD4 T-cells. In addition, adoptively transferred PVM-specific CD8+ T-cells, covering the entire PVM-specific CD8+ T-cell repertoire, provide partial protection from PVM-induced disease. From these data we infer that antigen-specific memory CD8+ T-cells offer significant protection to PVM-induced disease. Thus, CD8+ T-cells, despite being a major cause of PVM-associated pathology during primary infection, may offer promising targets of a protective pneumovirus vaccine. [Copyright &y& Elsevier]

In this pilot study, we hypothesize that waveform patterns of the celiac and cranial mesenteric arteries differ pre- and postprandially in normal dogs compared to those with chronic enteropathy. We further suggest that it is possible to classify these findings according to the type of disease present. Eleven dogs with chronic enteropathy and eight normal dogs were examined. Doppler examinations were performed at times 0 (fasted), and at 20, 40, 60 and 90 min post-prandially. The waveform shapes were described and the following features were extracted: resistive and pulsatility index, mean maximum velocity, mean diastolic velocity, peak systolic velocity, early diastolic notch ratio and the deceleration time interval. Dogs with inflammatory bowel disease had either lower or absent flow at fasting in early diastole compared to the other groups. Resistive and pulsatility indices decreased during digestion in all groups except those with protein losing enteropathy. The increase in mean diastolic flow daring digestion in affected dogs was either lacking (protein-losing enteropathy) or significantly lower (inflammatory bowel disease, P < 0.05) compared to normal dogs. Dogs with chronic enteropathies had abnormal arterial waveform shapes and suboptimal increases in diastolic blood flow during digestion and these findings worsened with the severity of the histological lesions present. Doppler ultrasound of the celiac and mesenteric arteries has great potential to enhance our understanding of intestinal disease in conscious dogs. [ABSTRACT FROM AUTHOR]

With global increases in anthropogenic pressures on wildlife populations comes a responsibility to manage them effectively. The assessment of marine ecosystem health is challenging and often relies on monitoring indicator species, such as cetaceans. Most cetaceans are however highly mobile and spend the majority of their time hidden from direct view, resulting in uncertainty on even the most basic population metrics. Here, we discuss the value of long-term and internationally combined stranding records as a valuable source of information on the demographic and mortality trends of the harbour porpoise (Phocoena phocoena) in the North Sea. We analysed stranding records (n = 16,181) from 1990 to 2017 and demonstrate a strong heterogeneous seasonal pattern of strandings throughout the North Sea, indicative of season-specific distribution or habitat use, and season-specific mortality. The annual incidence of strandings has increased since 1990, with a notable steeper rise particularly in the southern North Sea since 2005. A high density of neonatal strandings occurred specifically in the eastern North Sea, indicative of areas important for calving, and large numbers of juvenile males stranded in the southern parts, indicative of a population sink or reflecting higher male dispersion. These findings highlight the power of stranding records to detect potentially vulnerable population groups in time and space. This knowledge is vital for managers and can guide, for example, conservation measures such as the establishment of time-area-specific limits to potentially harmful human activities, aiming to reduce the number and intensity of human-wildlife conflicts. • International data synthesis to understand wildlife mortality and demographic trends • We demonstrate the value of long-term surveillance exemplified by stranding records. • Our analyses indicate potential vulnerable population groups in time and space. • Analytical methods allow establishment of robust baseline of spatiotemporal variation. • Results guide conservation measures aiming to reduce human-wildlife conflicts at sea. [ABSTRACT FROM AUTHOR]

In 2010, a mass die-off of over 1000 wild water frogs (Pelophylax spp.) and at least 10 common newts (Lissotriton vulgaris) occurred in a pond in The Netherlands. Haemorrhagic disease with hepatomegaly and splenomegaly was evident. Microscopically, multiple organs presented cells with multifocal intracytoplasmic inclusion bodies, in which ranavirus-like particles were demonstrated ultrastructurally. All specimens examined tested positive for ranavirus by PCR. The sequence obtained showed a 100% identity with the one deposited for common midwife toad virus (CMTV). This is the first report of ranavirus-associated mortality in wild amphibian populations in The Netherlands. It is also the first time CMTV or a CMTV-like virus has been reported in these two species in the adult stage and outside of Spain. [ABSTRACT FROM AUTHOR]