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1.
Equine Vet J ; 2024 Apr 09.
Article in English | MEDLINE | ID: mdl-38594893

ABSTRACT

BACKGROUND: The neuro-central synchondrosis (NCS) is a physis responsible for the growth of the dorsal third of the vertebral body and neural arches. When the NCS of pigs is tethered to model scoliosis, stenosis also ensues. It is necessary to describe the NCS for future evaluation of its potential role in equine spinal cord compression and ataxia (wobbler syndrome). OBJECTIVES: To describe the NCS, including when it and other physes closed in computed tomographic (CT) scans of the cervical spine of foals, due to its potential role in vertebral stenosis. STUDY DESIGN: Post-mortem cohort study. METHODS: The cervical spine of 35 cases, comprising both sexes and miscellaneous breeds from 153 gestational days to 438 days old, was examined with CT and physes scored from 6: fully open to 0: fully closed. The dorsal physis, physis of the dens and mid-NCS were scored separately, whereas the cranial and caudal NCS portions were scored together with the respective cranial and caudal vertebral body physes. RESULTS: The NCS was a pair of thin physes located in a predominantly dorsal plane between the vertebral body and neural arches. The mid-NCS was closed in C1 from 115 days of age, and in C2-C7 from 38 days of age. The dorsal physis closed later than the NCS in C1, and earlier than the NCS in C2-C7. The dens physis was closed from 227 days of age. The cranial and caudal physes were closing, but not closed from different ages in the different vertebrae of the oldest cases. MAIN LIMITATIONS: Hospital population. CONCLUSIONS: The NCS was a thin physis that contributed mainly to height-wise growth, but also width- and length-wise growth of the vertebral body and neural arches. The mid-NCS was closed in all cervical vertebrae from 115 days of age. The NCS warrants further investigation in the pathogenesis of vertebral stenosis.


HISTORIAL: La sincondrosis neuro­central (NCS) es la fisis responsable del crecimiento del tercio dorsal del cuerpo vertebral y de los arcos neurales. Cuando la NCS en cerdos se asocia a un modelo de escoliosis, también se produce estenosis. Es necesario describir la NCS para la futura evaluación de su rol potencial en la comprensión de la medula espinal equina y ataxia (síndrome de Wobbler). OBJETIVOS: Describir la NCS incluyendo cuando ella y otras fisis se cierran, por tomografía computarizada (CT) de la columna cervical de potrillos, debido a su rol potencial en la estenosis vertebral. DISEÑO DEL ESTUDIO: Estudio de cohorte post­mortem. MÉTODOS: La columna cervical de 35 casos, incluyendo ambos sexos y diferentes razas, desde 153 días gestacionales hasta 438 días de edad, fueron examinadas por CT y las fisis fueron dadas un puntaje de, 6: completamente abiertas a, 0: completamente cerradas. La fisis dorsal, la fisis del hueso odontoides y NCS media fueron evaluadas en forma separada, mientras las porciones de NCS craneal y caudal fueron evaluadas juntas con las respectiva fisis del cuerpo vertebral craneal y caudal. RESULTADOS: La NCS es un par de fisis delgadas localizadas predominantemente en el plano dorsal entre el cuerpo vertebral y los arcos vertebrales. La NCS media estaba cerrada en C1 desde los días 115 de edad, y en C2­C7 a partir de los 38 días de edad. La fisis dorsal se cerró más tarde que la NCS en C1, y antes que la NCS en C2­C7. La fisis del hueso odontoides estaba cerradas a partir de los 227 días de edad. Las fisis craneal y caudal estaban cerrándose, pero no estaban cerradas a distintas edades en las diferentes vertebras en los casos mayores de edad. LIMITACIONES PRINCIPALES: Población de hospital CONCLUSIONES: La NCS es una fisis delgada que contribuye principalmente al crecimiento en altura, pero también en ancho y largo del cuerpo vertebral y arcos vertebrales. La NCS media estaba cerrada en todas las vértebras cervicales a partir de los 115 días de edad. La NCS merece ser investigada más en la patogénesis de la estenosis vertebral. Palabras Clave: ataxia, tomografía computarizada, caballo, osteocondrosis, estenosis, crecimiento vertebral.

2.
J Wildl Dis ; 60(2): 461-473, 2024 04 01.
Article in English | MEDLINE | ID: mdl-38334201

ABSTRACT

Orf virus (genus Parapoxvirus) has been associated with gross skin lesions on muskoxen (Ovibos moschatus) from Victoria Island, Nunavut, Canada, where muskox populations are experiencing population declines. Orf virus causes painful proliferative and necrotizing dermatitis upon viral replication and shedding, which may lead to animal morbidity or mortality through secondary infections and starvation. Herpesvirus, known to cause gross lesions on skin and mucosa during active viral replication, has also been documented in muskoxen but to date has not been associated with clinical disease. Our objective was to characterize the variation of orf virus and herpesvirus in wild muskoxen of the Canadian Arctic. Tissue samples including gross skin lesions from the nose, lips, and/or legs were opportunistically collected from muskoxen on Victoria Island, Nunavut and Northwest Territories, and mainland Nunavut, Canada, from 2015 to 2017. Sampled muskoxen varied in age, sex, location, hunt type, and body condition. Tissues from 60 muskoxen were tested for genetic evidence of orf virus and herpesvirus infection using PCR targeting key viral genes. Tissues from 38 muskoxen, including 15 with gross lesions, were also examined for histological evidence of orf virus and herpesvirus infection. Eleven muskoxen (10 from Victoria Island and one from mainland Nunavut) with gross lesions had microscopic lesions consistent with orf virus infection. Muskox rhadinovirus 1, a gammaherpesvirus endemic to muskoxen, was detected in 33 (55%) muskoxen including 17 with gross lesions. In all tissues examined, there was no histological evidence of herpesvirus-specific disease. Sequencing and characterization of amplified PCR products using phylogenetic analysis indicated that a strain of orf virus, which appears to be unique, is likely to be endemic in muskoxen from Victoria Island and mainland Nunavut. Many of the muskoxen are also subclinically infected with a known muskox-endemic strain of herpesvirus.


Subject(s)
Herpesviridae Infections , Orf virus , Rhadinovirus , Animals , Canada/epidemiology , Orf virus/genetics , Phylogeny , Ruminants , Herpesviridae Infections/veterinary
3.
Article in English | MEDLINE | ID: mdl-38213106

ABSTRACT

STUDY DESIGN: Experimental porcine anterior cervical discectomy and fusion (ACDF) model: a proof-of-concept study. OBJECTIVE: The effect of monetite synthetic bone graft containing calcium pyrophosphate (Ca-PP) and ß-tricalcium phosphate (ß-TCP) on cervical spinal fusion in a non-instrumented two-level large animal model. SUMMARY OF BACKGROUND DATA: ACDF is the gold standard surgical technique for the treatment of degenerative cervical spinal diseases. However, pseudarthrosis associated with increased patient morbidity occurs in approximately 2,6% of the surgeries. Synthetic bone graft (SBG) may enhance bony fusion and subsequently decrease the risk of pseudarthrosis. Recent studies on monetite-based synthetic bone grafts for use in large cranial defects in humans have shown promising bone healing results, necessitating further investigation of their use in cervical spinal fusion. METHODS: Four adult female Danish Göttingen mini-pigs received partial cervical anterior discectomy and intervertebral defects at an upper and lower level. One defect was filled with SBG and the other was left empty. Bony fusion was evaluated using computed tomography (CT) at three-month intervals for 12 months. Fifteen months post-surgery, the animals were euthanized for further ex vivo qualitative histopathological and micro-CT evaluations. Fusion rates were compared using Fisher´s exact test at each time point. RESULTS: Increased interbody bony fusion rates were observed at synthetic bone graft levels (4/4) compared with control levels (0/4) evaluated by CT at 6- and 9-months post-surgery ( P = 0.029). Fusion was observed at all synthetic bone graft levels 12 months post-surgery and at only one control level. Histopathological evaluation confirmed high-quality interbody bony fusion at all synthetic bone graft levels, and fusion by spondylosis at one control level. CONCLUSION: This proof-of-concept study provides preliminary evidence of a novel, Ca-PP -and ß-TCP-containing monetite SBG that promotes bony fusion compared to a negative control in a clinically relevant porcine model of ACDF. LEVEL OF EVIDENCE: N/A.

4.
Pathogens ; 12(2)2023 Jan 25.
Article in English | MEDLINE | ID: mdl-36839459

ABSTRACT

Attraction sites are important for environmental pathogen transmission and spillover. Yet, their role in wildlife disease dynamics is often poorly substantiated. Herein, we study the role of salt licks as potential attraction sites for the spillover of gastrointestinal parasites from domestic sheep to wild reindeer. Eggs from the introduced sheep nematode Nematodirus battus were found in faecal samples of both species, suggestive of spillover. DNA metabarcoding of soil, collected at salt licks, revealed that N. battus, in addition to Teladorsagia circumcincta, were the most frequently occurring parasitic nematodes, with a significantly higher prevalence of nematodal DNA in salt lick soil compared to soil from control sites nearby. The finding of similar DNA haplotypes of N. battus in sheep, reindeer, and salt lick soil supports the hypothesis of spillover to reindeer via salt licks. More detailed investigation of the genetic diversity of N. battus across these hosts is needed to draw firm conclusions. Infection with these sheep nematodes could potentially explain a recently observed decline in the calf recruitment rate of the Knutshø reindeer herd. This study also supports the hypothesized role of artificial salt licks as hot spots for the transmission of environmentally persistent pathogens and illustrates the importance of knowledge about such attraction points in the study of disease in free-roaming animals.

5.
Pathogens ; 12(2)2023 Feb 07.
Article in English | MEDLINE | ID: mdl-36839541

ABSTRACT

Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy negatively impacting cervids on three continents. Soil can serve as a reservoir for horizontal transmission of CWD by interaction with the infectious prion protein (PrPCWD) shed by diseased individuals and from infected carcasses. We investigated the pathways for PrPCWD migration in soil profiles using lab-scale soil columns, comparing PrPCWD migration through pure soil minerals (quartz, illite and montmorillonite), and diverse soils from boreal (Luvisol, Brunisol) and prairie (Chernozem) regions. We analyzed the leachate of the soil columns by immunoblot and protein misfolding cyclic amplification (PMCA) and detected PrP in the leachates of columns composed of quartz, illite, Luvisol and Brunisol. Animal bioassay confirmed the presence of CWD infectivity in the leachates from quartz, illite and Luvisol columns. Leachates from columns with montmorillonite and prairie Chernozems did not contain PrP detectable by immunoblotting or PMCA; bioassay confirmed that the Chernozemic leachate was not infectious. Analysis of the solid phase of the columns confirmed the migration of PrP to lower layers in the illite column, while the strongest signal in the montmorillonite column remained close to the surface. Montmorillonite, the prevalent clay mineral in prairie soils, has the strongest prion binding ability; by contrast, illite, the main clay mineral in northern boreal and tundra soils, does not bind prions significantly. This suggests that in soils of North American CWD-endemic regions (Chernozems), PrPCWD would remain on the soil surface due to avid binding to montmorillonite. In boreal Luvisols and mountain Brunisols, prions that pass through the leaf litter will continue to move through the soil mineral horizon, becoming less bioavailable. In light-textured soils where quartz is a dominant mineral, the majority of the infectious prions will move through the soil profile. Local soil properties may consequently determine the efficiency of environmental transmission of CWD.

6.
J Wildl Dis ; 58(3): 550-561, 2022 07 01.
Article in English | MEDLINE | ID: mdl-35666850

ABSTRACT

Rabies is an important zoonotic disease with high fatality rates in animals and humans. In the Arctic, the Arctic fox (Vulpes lagopus) is regarded as the principal reservoir, but there is considerable debate about how the disease persists at the low population densities that are typical for this species. We describe an outbreak of rabies among Arctic foxes and Svalbard reindeer (Rangifer tarandus platyrhynchus) during 2011-12 on the remote Arctic archipelago of Svalbard, an area with a very low and relatively stable Arctic fox density. The aim of the research was to increase knowledge of Arctic rabies in this ecosystem and in the presumed spillover host, the Svalbard reindeer. Phylogenetic analysis of rabies virus (RABV) RNA isolates from Arctic fox and reindeer was performed, and clinical observations and histologic and immunohistochemical findings in reindeer were described. An ongoing capture-mark-recapture project allowed collection of serum samples from clinically healthy reindeer from the affected population for detection of rabies virus-neutralizing antibodies. The outbreak was caused by at least two different variants belonging to the RABV Arctic-2 and Arctic-3 clades, which suggests that rabies was introduced to Svalbard on at least two different occasions. The RABV variants found in Arctic fox and reindeer were similar within locations, suggesting that Arctic foxes and reindeer acquired the infection from the same source(s). The histopathologic and immunohistochemical findings in 10 reindeer were consistent with descriptions in other species infected with RABV of non-Arctic lineages. Evidence of RABV was detected in both brain and salivary gland samples. None of 158 examined serum samples from clinically healthy reindeer had virus-neutralizing antibodies against RABV.


Subject(s)
Rabies virus , Rabies , Reindeer , Animals , Antibodies, Neutralizing , Antibodies, Viral , Arctic Regions , Disease Outbreaks/veterinary , Ecosystem , Foxes , Humans , Norway/epidemiology , Phylogeny , Rabies/epidemiology , Rabies/veterinary , Svalbard
7.
Acta Vet Scand ; 64(1): 13, 2022 Jun 06.
Article in English | MEDLINE | ID: mdl-35668456

ABSTRACT

BACKGROUND: Chronic wasting disease (CWD) is a prion disease of cervids first reported in North America in the 1960s. In Europe, CWD was first diagnosed in 2016 in a wild reindeer in Norway. Detection of two more cases in the same mountain area led to the complete culling of this partially confined reindeer population of about 2400 animals. A total of 19 CWD positive animals were identified. The affected area is extensively used for the grazing of sheep during summers. There are many mineral licks intended for sheep in the area, but these have also been used by reindeer. This overlap in area use raised concerns for cross-species prion transmission between reindeer and sheep. In this study, we have used global positioning system (GPS) data from sheep and reindeer, including tracking one of the CWD positive reindeer, to investigate spatial and time-relevant overlaps between these two species. Since prions can accumulate in lymphoid follicles following oral uptake, samples of gut-associated lymphoid tissue (GALT) from 425 lambs and 78 adult sheep, which had grazed in the region during the relevant timeframe, were analyzed for the presence of prions. The recto-anal mucosa associated lymphoid tissue (RAMALT) from all the animals were examined by histology, immunohistochemistry (IHC) and enzyme-linked immunosorbent assay (ELISA), and the ileal Peyer's patch (IPP) from a subsample of 37 lambs were examined by histology and IHC, for the detection of prions. RESULTS: GPS data showed an overlap in area use between the infected reindeer herd and the sheep. In addition, the GPS positions of an infected reindeer and some of the sampled sheep showed temporospatial overlap. No prions were detected in the GALT of the investigated sheep even though the mean lymphoid follicle number in RAMALT and IPP samples were high. CONCLUSION: The absence of prions in the GALT of sheep that have shared pasture with CWD-infected reindeer, may suggest that transmission of this novel CWD strain to sheep does not easily occur under the conditions found in these mountains. We document that the lymphoid follicle rich RAMALT could be a useful tool to screen for prions in sheep.


Subject(s)
Deer , Prions , Reindeer , Sheep Diseases , Wasting Disease, Chronic , Animals , Norway , Sheep , Wasting Disease, Chronic/diagnosis , Wasting Disease, Chronic/epidemiology
8.
Mar Environ Res ; 177: 105625, 2022 May.
Article in English | MEDLINE | ID: mdl-35462230

ABSTRACT

Beachcast events, where a large number of seabird carcasses drift ashore, occur with irregular intervals. These events are due to specific situations where mass mortality of seabirds have occurred. Disentangling the cause of these events can provide valuable information on stressors impacting seabird populations. Following several mass mortality events involving gulls in northern Norway, an investigation of the probable cause of death was initiated. In total 75 dead gulls were collected at two occasions and necropsies were carried out. The findings from the necropsy of the gulls were consistent with drowning as the primary cause of death. Bycatch in coastal purse seine fishery was considered a potential cause of the mortality and monitoring of seabird bycatch in this fishery was thus initiated. The monitoring of fishing operations revealed that 10% of 91 fishing events observed led to bycatch, with a total of 32 bycaught seabirds. These bycatch events resulted in a total estimated bycatch rate of 0.356 (95% CI = 0.133-0.949) birds per haul. These findings are consistent with the hypothesis that the registered mortality events were caused by bycatch in the purse seine fishery. The highly episodic and unpredictable nature of these events makes it demanding to achieve solid estimates of the occurrence and extent of bycatch without a very high monitoring effort. Our study shows that systematic investigation following beachcast events can shed light on the occurrence of such extreme events.


Subject(s)
Charadriiformes , Fisheries , Animals , Birds , Conservation of Natural Resources , Norway
9.
J Infect Dis ; 226(5): 933-937, 2022 09 13.
Article in English | MEDLINE | ID: mdl-33502474

ABSTRACT

Chronic wasting disease (CWD) is the transmissible spongiform encephalopathy or prion disease affecting cervids. In 2016, the first cases of CWD were reported in Europe in Norwegian wild reindeer and moose. The origin and zoonotic potential of these new prion isolates remain unknown. In this study to investigate zoonotic potential we inoculated brain tissue from CWD-infected Norwegian reindeer and moose into transgenic mice overexpressing human prion protein. After prolonged postinoculation survival periods no evidence for prion transmission was seen, suggesting that the zoonotic potential of these isolates is low.


Subject(s)
Deer , Prions , Reindeer , Wasting Disease, Chronic , Animals , Deer/metabolism , Humans , Mice , Mice, Transgenic , Norway , Prions/genetics , Prions/metabolism , Reindeer/metabolism , Wasting Disease, Chronic/genetics
10.
J Wildl Dis ; 58(1): 228-231, 2022 01 01.
Article in English | MEDLINE | ID: mdl-34780597

ABSTRACT

Erysipelothrix rhusiopathiae was detected immunohistochemically in contagious ecthyma (orf virus) dermatitis in two muskoxen (Ovibos moschatus), harvested and found dead in 2014 and 2015, respectively, on Victoria Island, Canada. This may help target further research on E. rhusiopathiae epidemiology and mechanisms of infection in muskoxen, recently associated with widespread mortalities in Canada's Arctic.


Subject(s)
Dermatitis , Ecthyma, Contagious , Erysipelothrix , Sheep Diseases , Animals , Canada/epidemiology , Dermatitis/epidemiology , Dermatitis/veterinary , Ecthyma, Contagious/epidemiology , Ruminants , Sheep
11.
Int J Parasitol Parasites Wildl ; 15: 120-126, 2021 Aug.
Article in English | MEDLINE | ID: mdl-33996444

ABSTRACT

High host density combined with climate change may lead to invasion of harmful parasites in cervid (host) populations. Bot flies (Diptera: Oestridae) are a group of ectoparasites that may have strong impact on their hosts, but data on the current distribution, prevalence and intensity of the moose nose bot fly (Cephenemyia ulrichii) in Scandinavia are lacking. We estimated prevalence and intensity of nose bot fly larvae in 30 moose from southern and 79 moose from central Norway. All larvae detected were identified as the moose nose bot fly. We found surprisingly high prevalence in these areas, which are up to 1300 km south-southwest of the first published location in Norway and west of the distribution in Sweden. Prevalence (0.44-1.00) was higher in areas with higher moose density. Parasite intensity in hunter killed moose was higher in central Norway (mean 5.7) than southern Norway (mean 2.9), and in both regions higher in calves and yearlings than adults. Fallen moose had higher parasite intensity (mean 9.8) compared to hunter killed moose in the subsample from central Norway, suggesting a link to host condition or behavior. Our study provides evidence of parasite range expansion, and establishing monitoring appears urgent to better understand impact on host populations.

12.
J Wildl Dis ; 57(2): 282-291, 2021 04 01.
Article in English | MEDLINE | ID: mdl-33822153

ABSTRACT

In Norway, the Willow Ptarmigan (Lagopus lagopus lagopus) is experiencing population declines and is nationally Red Listed as Near Threatened. Although disease has not generally been regarded as an important factor behind population fluctuations for Willow Ptarmigan in Norway, disease occurrence has been poorly investigated. Both louping-ill virus (LIV) and the closely related tick-borne encephalitis virus are found along the southern part of the Norwegian coast. We assessed whether and where Norwegian Willow Ptarmigan populations have been infected with LIV. We expected to find infected individuals in populations in the southernmost part of the country. We did not expect to find infected individuals in populations further north and at higher altitudes because of the absence of the main vector, the sheep tick (Ixodes ricinus). We collected serum samples on Nobuto filter paper and used a hemagglutination inhibition assay for antibodies against LIV. We collected data at both local and country-wide levels. For local sampling, we collected and analyzed 87 hunter-collected samples from one of the southernmost Willow Ptarmigan populations in Norway. Of these birds, only three positives (3.4%) were found. For the country-wide sampling, we collected serum samples from 163 Willow Ptarmigan carcasses submitted from selected locations all over the country. Of these birds, 32% (53) were seropositive for LIV or a cross-reacting virus. Surprisingly, we found seropositive individuals from locations across the whole country, including outside the known distribution of the sheep tick. These results suggest that either LIV or a cross-reacting virus infects ptarmigan in large parts of Norway, including at high altitudes and latitudes.


Subject(s)
Bird Diseases/virology , Encephalitis Viruses, Tick-Borne/isolation & purification , Galliformes , Louping Ill/blood , Animals , Bird Diseases/epidemiology , Louping Ill/epidemiology , Norway/epidemiology , Seroepidemiologic Studies , Serologic Tests , Sheep
13.
Sci Rep ; 10(1): 22168, 2020 12 17.
Article in English | MEDLINE | ID: mdl-33335134

ABSTRACT

Prion diseases constitute a class of invariably fatal and degenerative encephalopathies. Chronic Wasting Disease (CWD) is a contagious prion disease among cervids, which is spreading and causing marked population declines in USA and Canada. The first outbreak of CWD in Europe was discovered in a reindeer population in Norway in 2016. In the worst-case scenario with continental-wide spreading of CWD in Eurasia, an annual harvest of around 4 million cervids is at stake only in Europe, with huge economic and cultural significance. An in situ origin of CWD was suspected, and it appear urgent to identify the likely cause to prevent future emergences. Here, we document the novel phenomenon of extensive antler cannibalism prior to shedding among reindeer in the CWD-infected population. The extent of antler cannibalism increased over the last decades when CWD emerged, and included ingestion of vascularized antlers. Ingestion of tissues from conspecifics is a risk factor for the emergence of prion diseases, where the presence of extensive antler cannibalism opens the intriguing possibility of a 'Kuru-analogue' origin of CWD among the reindeer in Europe. Based on general insight on pathology of prion diseases and strain selection processes, we propose an hypothesis for how contagious CWD may emerge from sporadic CWD under the unique epidemiological conditions we document here. More research is required to document the presence of prions in reindeer antlers, and whether antler cannibalism actually led to a strain selection process and the emergence of a contagious form of CWD from a sporadic form of CWD.


Subject(s)
Antlers , Cannibalism , Reindeer , Animals , Animals, Wild , Norway
14.
J Wildl Dis ; 56(3): 687-692, 2020 07.
Article in English | MEDLINE | ID: mdl-32195641

ABSTRACT

The deer ked (Lipoptena cervi), a hematophagous ectoparasite of cervids, is currently spreading in Scandinavia, and the moose (Alces alces) is its main host. However, little is known about the impact of deer keds on moose. We analyzed the hair cortisol concentration (HCC) from 262 moose harvested in the fall in relation to age class, sex, body mass (BM), and deer ked infestation intensity, and BM in relation to age class, sex, and infestation intensity. We found that HCC decreased with increasing deer ked intensity at low ked intensities, but for the higher levels of ked intensities, there was a positive relationship between HCC and ked intensity. The HCC was higher in males than in females and lower in yearlings than in calves and adults. Our failure to find any association between BM and deer ked intensity suggested a negligible impact of deer ked infestation on moose foraging and metabolism at the level of infestation observed early in the infestation, but did not exclude an effect later in winter. Our findings suggested that moose generally tolerated moderate parasitism by keds. However, the increase in HCC at higher ked intensities suggested that the tolerance strategy could be disrupted with further increases in intensities and consequently may negatively affect animal health and welfare.


Subject(s)
Deer/parasitology , Diptera , Hair/chemistry , Hydrocortisone/metabolism , Myiasis/veterinary , Aging , Animals , Body Weight , Female , Hydrocortisone/chemistry , Male , Myiasis/parasitology , Myiasis/pathology , Norway
15.
Ambio ; 49(3): 805-819, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31187429

ABSTRACT

Muskoxen (Ovibos moschatus) are an integral component of Arctic biodiversity. Given low genetic diversity, their ability to respond to future and rapid Arctic change is unknown, although paleontological history demonstrates adaptability within limits. We discuss status and limitations of current monitoring, and summarize circumpolar status and recent variations, delineating all 55 endemic or translocated populations. Acknowledging uncertainties, global abundance is ca 170 000 muskoxen. Not all populations are thriving. Six populations are in decline, and as recently as the turn of the century, one of these was the largest population in the world, equaling ca 41% of today's total abundance. Climate, diseases, and anthropogenic changes are likely the principal drivers of muskox population change and result in multiple stressors that vary temporally and spatially. Impacts to muskoxen are precipitated by habitat loss/degradation, altered vegetation and species associations, pollution, and harvest. Which elements are relevant for a specific population will vary, as will their cumulative interactions. Our summaries highlight the importance of harmonizing existing data, intensifying long-term monitoring efforts including demographics and health assessments, standardizing and implementing monitoring protocols, and increasing stakeholder engagement/contributions.


Subject(s)
Ecosystem , Ruminants , Animals , Arctic Regions , Biodiversity , Uncertainty
16.
J Wildl Dis ; 55(4): 970-972, 2019 10.
Article in English | MEDLINE | ID: mdl-30920905

ABSTRACT

Chronic wasting disease (CWD) is a fatal contagious prion disease naturally occurring in cervids in North America. In 2016, CWD was detected in wild reindeer (Rangifer tarandus) and moose (Alces alces) in Norway. Here, we report the first known naturally infected wild Norwegian red deer (Cervus elaphus).


Subject(s)
Deer , Wasting Disease, Chronic/epidemiology , Animals , Brain/pathology , Female , Norway/epidemiology , Prions/isolation & purification , Wasting Disease, Chronic/pathology
17.
Front Vet Sci ; 5: 252, 2018.
Article in English | MEDLINE | ID: mdl-30374443

ABSTRACT

Intraperitoneal radio transmitters have been widely used in free-ranging wild mammals, but there are no long-term studies on their biocompatibility or technical stability within the abdominal cavity of animals. Possible negative health effects may bias results from ecological studies on instrumented animals and raise concerns over animal welfare issues. The aim of this study was to evaluate the long-term technical stability and pathological effects of Telonics intraperitoneal very high frequency (VHF) radio transmitters in brown bears (Ursus arctos). We instrumented 305 individual bears with intraperitoneal VHF radio transmitters during a 19-year period. We surgically removed devices that had been in bears for 1-9 years and collected transmitters from animals that died 1-13 years after implantation. We took biopsies for histopathology from tissue encapsulating implants in live bears. Retrieved transmitters underwent a technical inspection. Of the 125 transmitters removed from live bears, 66 were free-floating in the peritoneal cavity [a mean (SD) of 3.8 (1.5) years after implantation], whereas 59 were encapsulated in the greater omentum [4.0 (1.8) years after implantation]. Histopathology of biopsies of the 1-15 mm thick capsules in 33 individuals showed that it consisted of organized layers of connective tissue. In one third of the bears, the inner part of the capsule was characterized by a foreign body reaction. We inspected 68 implants that had been in bears for 3.9 (2.4) years. The batteries had short-circuited four (5.9%) of these devices. This resulted in the death of two animals 10 and 13 years after implantation. In two other bears that underwent surgery, we found the short-circuited devices to be fully encapsulated within the peritoneal cavity 5 and 6 years after implantation. A significant proportion of the other 64 inspected implants showed serious technical problems, such as corrosion of metal parts or the batteries (50%), detachment of the end cap (11.8%), and erosion (7.4%) or melting (5.9%) of the wax coating. We conclude that the wax coating of the transmitters was not biocompatible, that the technical quality of the devices was poor, and that these implants should not be used in brown bears.

18.
Sci Rep ; 8(1): 13786, 2018 09 13.
Article in English | MEDLINE | ID: mdl-30214004

ABSTRACT

Shooting is an important tool for managing terrestrial wildlife populations worldwide. To date, however, there has been few quantitative methods available enabling assessment of the animal welfare outcomes of rifle hunting. We apply a variety of factors to model flight distance (distance travelled by an animal after bullet impact) and incapacitation from the moment of bullet impact. These factors include body mass, allometric and isometric scaling, comparative physiology, wound ballistics and linear kinematics. This approach provides for the first time a method for quantifying and grading the quality of shooting processes by examining only body mass and flight distance. Our model is a universally applicable tool for measuring animal welfare outcomes of shooting regimes both within and among species. For management agencies the model should be a practical tool for monitoring and evaluating animal welfare outcomes regarding shooting of mammalian populations.


Subject(s)
Animal Culling/methods , Animal Welfare/statistics & numerical data , Escape Reaction/physiology , Firearms/statistics & numerical data , Forensic Ballistics/statistics & numerical data , Animals , Animals, Wild , Body Mass Index , Deer/physiology , Foxes/physiology , Models, Theoretical , Ursidae/physiology
19.
Vet Res ; 47(1): 88, 2016 09 15.
Article in English | MEDLINE | ID: mdl-27641251

ABSTRACT

Chronic wasting disease (CWD) is a fatal contagious prion disease in cervids that is enzootic in some areas in North America. The disease has been found in deer, elk and moose in the USA and Canada, and in South Korea following the importation of infected animals. Here we report the first case of CWD in Europe, in a Norwegian free-ranging reindeer in Southern Norway. The origin of the disease is unknown. Until now a low number of cervids, and among them a few reindeer, have been tested for CWD in Norway. Therefore the prevalence of CWD is unknown.


Subject(s)
Reindeer , Wasting Disease, Chronic/epidemiology , Animals , Blotting, Western/veterinary , Brain/pathology , Female , Norway/epidemiology , Wasting Disease, Chronic/diagnosis , Wasting Disease, Chronic/pathology
20.
Parasit Vectors ; 9: 95, 2016 Feb 20.
Article in English | MEDLINE | ID: mdl-26897626

ABSTRACT

BACKGROUND: The deer ked (Lipoptena cervi) is an ectoparasite on cervids that has invaded large parts of Norway, Sweden and Finland during recent decades. During their host-seeking flight activity, the adult deer keds constitute a considerable nuisance to people and limit human outdoor recreation. The bites of the deer ked can cause long-lasting dermatitis in humans. Determining the pattern of flight activity during autumn is hence important. METHODS: Data on flight phenology was gathered by walking along transects in the forest in two counties of Norway during 2009-2013, counting the number of host-seeking keds. We analysed how the flight activity of deer keds varied depending on date and prevailing weather during autumn. RESULTS: The best model of flight activity included both date and temperature, both as nonlinear terms. Host-seeking deer keds were observed from early August to mid-November with a marked peak in late September. Number of host-seeking keds declined with temperatures falling below the mean, but did not increase much at above mean temperatures. The pattern of flight phenology was similar across the two counties and five years. CONCLUSIONS: Parasitic arthropods may be strongly affected by prevailing weather during off-host periods. Our study shows an estimated positive effect of temperature on deer ked flight activity mainly for below mean temperatures in late autumn, while the effect of temperature on flight activity in early autumn was weak. The pattern of host-seeking flight activity during late, rather than early autumn, is hence more likely to change with ongoing climate change, with a predicted increase in duration of the host-seeking period.


Subject(s)
Behavior, Animal , Deer/parasitology , Diptera/physiology , Locomotion , Animals , Humans , Norway , Seasons , Temperature , Weather
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