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Abstract: Philometra rubra (Leidy, 1856) is a pathogenic parasitic nematode infecting striped bass (Morone saxatilis (Walbaum, 1792)) in eastern North America. Identification of philometrids is difficult, male P. rubra have [...]

An isolated population of beluga (Delphinapterus leucas) inhabits the St Lawrence Estuary, Quebec, Canada. This population has failed to recover despite the prohibition of hunting >30 years ago, suggesting the presence of other limiting factors. The authors summarize the reported causes of death and propose risk factors to explain the lack of recovery of this population. From 1983 to 2012, a total of 472 beluga were found stranded. Complete necropsies were carried out on 222 beluga, including 178 adults, 25 juveniles, and 19 newborn calves. Infectious diseases, the most prevalent cause of mortality in this population, accounted for the death of one-third of all beluga (32%). Verminous pneumonia was the cause of mortality of 13 juvenile beluga (52% of juvenile beluga). A total of 39 malignant neoplasms, diagnosed in 35 beluga, caused the death of 31 beluga (20% of beluga >19 years old). Median age at diagnosis of cancer was 48 years (range, 30–61 years). Dystocia and postpartum complications were the cause of death in 18 beluga, accounting for 19% of the females >19 years old examined. The occurrence of parturition-associated complications, as well as mortality of calves <1 year old, have increased recently in this population and may be the probable cause of the recent decrease in the size of this population. One of the hypotheses proposed to explain the unusually high occurrence of some of the pathologic conditions observed in this population is chronic exposure to environmental contaminants. [ABSTRACT FROM AUTHOR]

Intestinal volvulus was recognized as the cause of death in 18 cetaceans, including 8 species of toothed whales (suborder Odontoceti). Cases originated from 11 institutions from around the world and included both captive (n = 9) and free-ranging (n = 9) animals. When the clinical history was available (n = 9), animals consistently demonstrated acute dullness 1 to 5 days prior to death. In 3 of these animals (33%), there was a history of chronic gastrointestinal illness. The pathological findings were similar to those described in other animal species and humans, and consisted of intestinal volvulus and a well-demarcated segment of distended, congested, and edematous intestine with gas and bloody fluid contents. Associated lesions included congested and edematous mesentery and mesenteric lymph nodes, and often serofibrinous or hemorrhagic abdominal effusion. The volvulus involved the cranial part of the intestines in 85% (11 of 13). Potential predisposing causes were recognized in most cases (13 of 18, 72%) but were variable. Further studies investigating predisposing factors are necessary to help prevent occurrence and enhance early clinical diagnosis and management of the condition. [ABSTRACT FROM AUTHOR]

A survey of external lesions on Atlantic tomcod from the St Lawrence River was carried out between mid-December 1992 and the end of January 1993 (n = 1674). Jaw ulcerations were observed in 3.8% of the fish. These ulcers were usually single, and located at the junction between the skin epidermis and oral mucosa. They progressed from shallow lesions to deep ulcers with pathological fracture of the facial bone secondary to osteitis. The aetiology of these lesions could not be determined. Fish with ulcers were generally older than those of the monitored spawning population. The reason for a higher prevalence in older tomcods is unknown, but decreased immune functions and healing capacity caused by ageing are suggested as potential predisposing factors. [ABSTRACT FROM AUTHOR]

Abstract Background In high grade gliomas, 1p19q codeletion and EGFR amplification are mutually exclusive and predictive of dramatically different outcomes. We performed a microarray gene expression study of four high grade gliomas with 1p19q codeletion and nine with EGFR amplification, identified by CGH-array. Results The two groups of gliomas exhibited very different gene expression profiles and were consistently distinguished by unsupervised clustering analysis. One of the most striking differences was the expression of normal brain genes by oligodendrogliomas with 1p19q codeletion. These gliomas harbored a gene expression profile that partially resembled the gene expression of normal brain samples, whereas gliomas with EGFR amplification expressed many genes in common with glioblastoma cancer stem cells. The differences between the two types of gliomas and the expression of neuronal genes in gliomas with 1p19q codeletion were both validated in an independent series of 16 gliomas using real-time RT-PCR with a set of 22 genes differentiating the two groups of gliomas (AKR1C3, ATOH8, BMP2, C20orf42, CCNB1, CDK2, CHI3L1, CTTNBP2, DCX, EGFR, GALNT13, GBP1, IGFBP2, IQGAP1, L1CAM, NCAM1, NOG, OLIG2, PDPN, PLAT, POSTN, RNF135). Immunohistochemical study of the most differentially expressed neuronal gene, alpha-internexin, clearly differentiated the two groups of gliomas, with 1p19q codeletion gliomas showing specific staining in tumor cells. Conclusion These findings provide evidence for neuronal differentiation in oligodendrogliomas with 1p19q codeletion and support the hypothesis that the cell of origin for gliomas with 1p19q codeletion could be a bi-potential progenitor cell, able to give rise to both neurons and oligodendrocytes.

A necropsy was performed on a Common Raven ( Corvus corax ) presenting an opportunistic fungal respiratory infection and a bursal lymphoid depletion with inclusion bodies, suggestive of a circovirus infection. High-throughput sequencing of circular DNA in the bursa of Fabricius revealed a complete genome sequence of a Circovirus pigeon strain., Competing Interests: The authors declare no conflict of interest.

The last few years have seen a surge of interest from field ecologists and evolutionary biologists to study neoplasia and cancer in wildlife. This contributes to the One Health Approach, which investigates health issues at the intersection of people, wild and domestic animals, together with their changing environments. Nonetheless, the emerging field of wildlife cancer is currently constrained by methodological limitations in detecting cancer using non-invasive sampling. In addition, the suspected differential susceptibility and resistance of species to cancer often make the choice of a unique model species difficult for field biologists. Here, we provide an overview of the importance of pursuing the study of cancer in non-model organisms and we review the currently available methods to detect, measure and quantify cancer in the wild, as well as the methodological limitations to be overcome to develop novel approaches inspired by diagnostic techniques used in human medicine. The methodology we propose here will help understand and hopefully fight this major disease by generating general knowledge about cancer, variation in its rates, tumour-suppressor mechanisms across species as well as its link to life history and physiological characters. Moreover, this is expected to provide key information about cancer in wildlife, which is a top priority due to the accelerated anthropogenic change in the past decades that might favour cancer progression in wild populations., (© 2024 The Author(s). Journal of Animal Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society.)

Introduction: This study aimed to evaluate the color and the discriminating compounds for two types of cocoa beans (black and brown beans) related to 70% dark chocolates of black and brown colors from a previous work of our group., Methods: Color analysis and untargeted high-resolution mass spectrometry-based metabolomic analysis were performed on eight beans of each type. Mass spectral data processing, univariate and multivariate statistical methods were conducted for classification of beans and selection of discriminant features., Results and Discussion: The results showed that the color difference already observed for black and brown chocolates preexists in the beans. Black and brown beans had 45 and 50 discriminant features, respectively, of which 16 and 41 were phenolic compounds. Most of them were also previously identified as discriminating compounds for black and brown chocolates. Black beans predominantly contained glycosylated flavanols, ranging from monomers to trimers, with dimers and trimers being A-type procyanidins, along with a phenolic acid (protocatechuic acid), and an O-glycosylated flavonol (quercetin-3-O-glucoside). In contrast, brown beans mostly contained non-glycosylated B-type procyanidins ranging from dimers to decamers, but also dimers and trimers of A-type procyanidins, and a glycosylated and sulfated flavanol ((epi) catechin hexoside-sulfate). These markers may be useful for quality control purposes and may contribute to the selection of beans that yield black or brown dark chocolates., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 de Sousa Dias, Meudec, Verbaere, Lair, Boulet and Sommerer.)

Carcasses of endangered beluga whales Delphinapterus leucas from the St. Lawrence Estuary, Canada, have been examined consistently since 1983 to determine causes of death. The objective of this study is to compare the nutritional condition of belugas that died of different causes. Previously published categories of death were refined to discriminate acute from chronic pathological processes. Bayesian linear models were used to predict cause of death from the scaled mass index (SMI). Causes of death were as follows: 'bacterial diseases', 'verminous pneumonia', 'toxoplasmosis', 'other parasitic diseases', 'other infectious diseases', 'trauma-entrapment', 'other noninfectious diseases', 'dystocia-postpartum complications', 'neonatal mortality', 'cancer', 'primary starvation' and 'undetermined'. The models predicted a lower nutritional condition for the 'neonatal mortality' in belugas <290 cm in length and for 'primary starvation' and 'verminous pneumonia' categories for belugas ≥290 cm. Belugas that died from 'dystocia-postpartum complications' or from 'undetermined causes' had a higher-than-average SMI. Animals in the 'trauma-entrapment' category did not exhibit the highest nutritional condition, which was unexpected since individuals that died from trauma or entrapment are often used as references for optimal nutritional condition in other cetacean populations. Females that died from dystocia and postpartum complications were in similar nutritional condition as females dead from other causes during, or shortly after, pregnancy. This suggests that these females are not obese, ruling out a possible cause of dystocia. Although studying dead animals biases results toward low nutritional condition, our findings support the link between chronic pathological processes and poorer nutritional condition in belugas.

Following the detection of novel highly pathogenic avian influenza virus (HPAIV) H5N1 clade 2.3.4.4b in Newfoundland, Canada, in late 2021, avian influenza virus (AIV) surveillance in wild birds was scaled up across Canada. Herein, we present the results of Canada's Interagency Surveillance Program for Avian Influenza in Wild Birds during the first year (November 2021-November 2022) following the incursions of HPAIV from Eurasia. The key objectives of the surveillance program were to (i) identify the presence, distribution, and spread of HPAIV and other AIVs; (ii) identify wild bird morbidity and mortality associated with HPAIV; (iii) identify the range of wild bird species infected by HPAIV; and (iv) genetically characterize detected AIV. A total of 6,246 sick and dead wild birds were tested, of which 27.4% were HPAIV positive across 12 taxonomic orders and 80 species. Geographically, HPAIV detections occurred in all Canadian provinces and territories, with the highest numbers in the Atlantic and Central Flyways. Temporally, peak detections differed across flyways, though the national peak occurred in April 2022. In an additional 11,295 asymptomatic harvested or live-captured wild birds, 5.2% were HPAIV positive across 3 taxonomic orders and 19 species. Whole-genome sequencing identified HPAIV of Eurasian origin as most prevalent in the Atlantic Flyway, along with multiple reassortants of mixed Eurasian and North American origins distributed across Canada, with moderate structuring at the flyway scale. Wild birds were victims and reservoirs of HPAIV H5N1 2.3.4.4b, underscoring the importance of surveillance encompassing samples from sick and dead, as well as live and harvested birds, to provide insights into the dynamics and potential impacts of the HPAIV H5N1 outbreak. This dramatic shift in the presence and distribution of HPAIV in wild birds in Canada highlights a need for sustained investment in wild bird surveillance and collaboration across interagency partners., Importance: We present the results of Canada's Interagency Surveillance Program for Avian Influenza in Wild Birds in the year following the first detection of highly pathogenic avian influenza virus (HPAIV) H5N1 on the continent. The surveillance program tested over 17,000 wild birds, both sick and apparently healthy, which revealed spatiotemporal and taxonomic patterns in HPAIV prevalence and mortality across Canada. The significant shift in the presence and distribution of HPAIV in Canada's wild birds underscores the need for sustained investment in wild bird surveillance and collaboration across One Health partners., Competing Interests: The authors declare no conflict of interest.

We describe an unusual mortality event caused by a highly pathogenic avian influenza (HPAI) A(H5N1) virus clade 2.3.4.4b involving harbor (Phoca vitulina) and gray (Halichoerus grypus) seals in the St. Lawrence Estuary, Quebec, Canada, in 2022. Fifteen (56%) of the seals submitted for necropsy were considered to be fatally infected by HPAI H5N1 containing fully Eurasian or Eurasian/North American genome constellations. Concurrently, presence of large numbers of bird carcasses infected with HPAI H5N1 at seal haul-out sites most likely contributed to the spillover of infection to the seals. Histologic changes included meningoencephalitis (100%), fibrinosuppurative alveolitis, and multiorgan acute necrotizing inflammation. This report of fatal HPAI H5N1 infection in pinnipeds in Canada raises concerns about the expanding host of this virus, the potential for the establishment of a marine mammal reservoir, and the public health risks associated with spillover to mammals.Nous décrivons un événement de mortalité inhabituelle causé par un virus de l'influenza aviaire hautement pathogène A(H5N1) clade 2.3.4.4b chez des phoques communs (Phoca vitulina) et gris (Halichoerus grypus) dans l'estuaire du Saint-Laurent au Québec, Canada, en 2022. Quinze (56%) des phoques soumis pour nécropsie ont été considérés comme étant fatalement infectés par le virus H5N1 de lignées eurasiennes ou de réassortiment eurasiennes/nord-américaines. Un grand nombre simultané de carcasses d'oiseaux infectés par le H5N1 sur les sites d'échouement a probablement contribué à la contamination de ces phoques. Les changements histologiques associés à cette infection incluaient : méningo-encéphalite (100%), alvéolite fibrinosuppurée et inflammation nécrosante aiguë multi-organique. Cette documentation soulève des préoccupations quant à l'émergence de virus mortels, à la possibilité d'établissement de réservoirs chez les mammifères marins, et aux risques pour la santé publique associés aux propagations du virus chez les mammifères.

Of the 202 species of Chamaeleonidae, 38.6% are globally threatened. Currently, nearly a thousand individual chameleons from 36 different species are kept in zoological institutions worldwide. The objectives of this study were to assess the main mortality causes of chameleons in zoological institutions, the prevalence of renal lesions at necropsy, and the environmental factors associated with renal lesions. An online survey was sent to 245 zoological institutions worldwide to collect information about species and sex distribution, necropsy results, and husbandry parameters. Necropsy reports of the last 10 yr were requested from participating institutions ( n = 65) when available. Mortality causes were classified into three categories (open diagnosis, infectious, and noninfectious), and noninfectious causes were further subdivided into seven categories (renal, reproductive, myoarthroskeletal, digestive, ophthalmologic, denutrition/multisystemic, and neoplastic). The prevalence of renal lesions was recorded. Multiple linear regression models were used with the prevalence of renal diseases as the dependent variable, and exhibit minimum and maximum hygrometry; exhibit highest and coolest temperature; as well as minimum, mean, and maximum hygrometry of the geographical area as independent variables, combining all chameleon species with similar environmental requirements. Results were obtained for 14 species ( n = 412 individuals). The main mortality causes were infectious (46.8%), noninfectious renal (11.4%), and noninfectious reproductive (10.7%) diseases, with all cases of fatal reproductive diseases reported in females. Of the individuals that underwent renal histopathology, 41.7% displayed renal lesions. There was a tendency towards higher renal lesion prevalence in zoos located in areas with lower mean hygrometry ( P = 0.05). Further research studies about infectious, renal, and reproductive diseases of Chamaeleonidae are warranted.

The striped bass ( Morone saxatilis ) has been a fish species of special concern in Canada since its marked decline in the early 21st century in the St. Lawrence River. Individuals kept in public aquaria contribute to public education and could support conservation efforts through research. Over a 3-yr period, 12 male striped bass housed in a multispecies exhibit developed coelomic distension. The testes were enlarged (12/12), cystic (2/12), and heterogeneous (3/12) on coelomic ultrasound. Upon coeliotomy, enlarged (12/12), partially (4/12) or totally white discolored (6/12) testes were noted. These were associated with coelomic hemorrhage (8/12), effusion (3/12) or adhesions to surrounding organs (9/12). Orchiectomies were performed in all fish. Among these, seven fish survived 2 mon postsurgery, and four fish were still alive 900 d postsurgery. Germ cell neoplasia was diagnosed on histopathological examination in 9 of 12 individuals, but no abnormalities were found in the three other cases. Preventive orchiectomies were performed on the remaining six male striped bass in this exhibit. Germ cell neoplasms were present in two of these six fish. No anesthetic or surgical complications were noted; all six cases were alive 2 mon postsurgery and four of the fish survived 900 d postsurgery. Survival times were not significantly different between fish that underwent preventive or curative orchiectomy ( P = 0.19). Although risk factors associated with the development of these gonadal tumors remain unknown, a genetic or environmental origin is suspected. Orchiectomy should be considered in suspected cases of testicular tumors.