Distribution, prevalence and intensity of moose nose bot fly (Cephenemyia ulrichii) larvae in moose (Alces alces) from Norway (original) (raw)

Deer ked, an ectoparasite of moose in Finland: a brief review of its biology and invasion

The deer ked (Lipoptena cervi) is an important ectoparasite of moose (Alces alces) that has rapidly invaded Finland during the last 50 years, and is currently found in southern parts of Finnish Lapland. We have studied the invasion, behavior, and ecology of this parasitic fly, and in this paper briefly review the effect of climate on the distribution of deer keds and our recent findings from host-choice experiments. The rapid increase of the deer ked is correlated with high moose densities in Finland. We propose that the availability of suitable hosts, not climate, is the primary factor affecting its northward range expansion. Our host-choice experiments indicated that deer keds are attracted by movement and large, dark objects. Our results suggest that this parasite may continue to spread northwards in the near future, and that its potential impact on cervids and human health warrants attention.

Emergence of the arterial worm Elaeophora schneideri in moose (Alces alces) and tabanid fly vectors in northeastern Minnesota, USA

Parasites & Vectors, 2018

Background: Moose (Alces alces) are a culturally and economically valued species in Minnesota. However, the moose population has experienced a sudden, marked decline in their range, including extirpation in the northwest and a 66% decline in the last decade in the northeast portions of the state. Although the exact cause of this decline is unclear, parasitic metastrongylid and filarioid nematode infections are known causes of morbidity and mortality in moose across North America. Methods: To determine if these parasitic nematodes could be contributing to the Minnesota moose population decline, we molecularly examined banked tissues obtained from moose that died of known and unknown causes for the presence of nematode DNA. Extracted brain DNA of 34 individual moose was amplified utilizing primers targeting the 18S rRNA gene and internal transcribed spacer regions of nematodes. Results: DNA sequencing revealed that PCR products obtained from 15 (44.1%) of the moose were 99% identical to Parelaphostrongylus tenuis, a metastrongylid known to cause neurological disease and death. Additionally, brain tissue from 20 (58.8%) individuals yielded sequences that most closely aligned with Elaeophora schneideri, a parasite associated with neurological impairment but previously unreported in Minnesota. Setaria yehi, a common filarioid parasite of deer, was also detected in the brain tissue of 5 (14.7%) moose. Molecular screening of 618 captured tabanid flies from four trapping sites revealed E. schneideri was present (6%) in the Minnesota environment and transmission could occur locally. Prevalence rates among the flies ranged between 0-100% per trapping site, with Chrysops spp. and Hybomitra spp. implicated as the vectors. Conclusions: Ultimately, these data confirm that P. tenuis is widespread in the Minnesota moose population and raises the question of the significance of E. schneideri as a contributing factor to morbidity and mortality in moose.

Sources of variation in endohelminth parasitism of common eiders over-wintering in the Canadian Arctic

Polar Biology, 2018

Documenting how climate change will affect Arctic ecosystems and food web dynamics requires an understanding of current sources of variation in species distributions, frequency, and abundance. Host-parasite interactions are expected to be altered in the coming decades under warming conditions. However, in many Polar Regions, there is little information describing parasite-host assemblages. We examine how gastrointestinal helminths of northern common eider ducks (Somateria mollissima sedentaria) in the low Arctic vary with host age, sex and sampling year. We found that the prevalence of an acanthocephalan (Profilicollus sp.) varied in eiders with age, sex and year, while a cestode (Microsomacanthus sp.) varied with host sex. Two other species of endohelminths (Lateriporus sp., Corysonoma sp.) were not found to vary with sex, age or sampling year, and another species (Microphallus sp.) did not vary with sex or age. Our results highlight the complexity inherent in Arctic host-parasite assemblages, and the need for more detailed studies to better understand how changing climatic conditions may affect species distributions, frequency or abundance.

Factors affecting deer ked (Lipoptena cervi) prevalence and infestation intensity in moose (Alces alces) in Norway

Parasites & Vectors, 2012

Background: The deer ked (Lipoptena cervi), a hematophagous ectoparasite of Cervids, is currently spreading in Scandinavia. In Norway, keds are now invading the south-eastern part of the country and the abundant and widely distributed moose (Alces alces) is the definitive host. However, key factors for ked abundance are poorly elucidated. The objectives of our study were to (i) determine deer ked infestation prevalence and intensity on moose and (ii) evaluate if habitat characteristics and moose population density are determinants of deer ked abundance on moose. Methods: In order to identify key factors for deer ked abundance, a total of 350 skin samples from the neck of hunted moose were examined and deer keds counted. Infestation intensity was analyzed in relation to moose age and sex, moose population density and landscape characteristics surrounding the killing site. Results: Deer ked infestation prevalence was 100%, but infestation intensity varied from 0.001 to 1.405 keds/cm 2 . Ked intensity was highest in male yearlings (~1.5 years) and positively associated with longitude and Scots pine (Pinus sylvestris) dominated habitat and negatively associated with bogs and latitude. Moose population density during autumn showed a tendency to be positively associated, while altitude tended to be negatively associated with ked intensity. Conclusions: Deer keds exploit the whole moose population within our study area, but are most prevalent in areas dominated by Scots pine. This is probably a reflection of Scots pine being the preferred winter browse for moose in areas with highest moose densities in winter. Ked intensity decreases towards the northwest and partly with increasing altitude, probably explained by the direction of dispersal and reduced temperature, respectively. Abundant deer ked harm humans and domestic animals. Moose management authorities should therefore be aware of the close relationship between moose, deer ked and habitat, using the knowledge as a management tool for locally regulating the ked burden.

REVIEW OF DEER KED (LIPOPTENA CERVI) ON MOOSE IN SCANDINAVIA WITH IMPLICATIONS FOR NORTH AMERICA

… Management of Moose, 2012

The deer ked (Lipoptena cervi) is an Old World dipteran ectoparasite of moose (Alces alces) and other Cervidae. It has undergone significant expansion in distribution on moose of Scandinavia in recent decades. This has been accompanied by much published research dealing with the range expansion and possible factors involved, problems for moose, exposure of northern populations of reindeer (Rangifer rangifer tarandus), and public health issues. Apparently, Lipoptena cervi was introduced into northeastern United States in the late 1800s, presumably on an unknown species of European deer, and it soon spread to white-tailed deer (Odocoileus virginianus). We review the current situation in Scandinavia and North America and document the first record of L. cervi on moose in northeastern United States.

Epizootiology of Elaphostrongylus Alces in Swedish Moose

2016

A total of 961 harvested and 241 unharvested moose ( Alces alces ) carcasses and parts from throughout Sweden were examined for Elaphostrongylus alces from 1985 to 1989. When available, the central nervous system and skeletal muscles were searched for adult nematodes, and lungs and feces were examined for first-stage larvae. The parasite was distributed throughout Sweden with highest prevalence (56%) in the central region and lowest in the south (13%). Prevalence was highest in calves and old moose (>9 years) and lowest in middle-aged animals (5–9 years), with no statistical difference between sexes, although prevalence trended higher in young males. Body condition and abundance of Elaphostrongylus alces were negatively correlated, and condition was poorer in unharvested than harvested moose. A short (39–73 days) prepatent period was documented, and calves as young as 1.5 months were infected. These results indicate the importance of continued surveillance of Elaphostrongylus alc...

Parasites in ungulates of Arctic North America and Greenland: a view of contemporary diversity, ecology, and impact in a world under change

Advances in parasitology, 2012

Parasites play an important role in the structure and function of arctic ecosystems, systems that are currently experiencing an unprecedented rate of change due to various anthropogenic perturbations, including climate change. Ungulates such as muskoxen, caribou, moose and Dall's sheep are also important components of northern ecosystems and are a source of food and income, as well as a focus for maintenance of cultural traditions, for northerners. Parasites of ungulates can influence host health, population dynamics and the quality, quantity and safety of meat and other products of animal origin consumed by people. In this article, we provide a contemporary view of the diversity of nematode, cestode, trematode, protozoan and arthropod parasites of ungulates in arctic and subarctic North America and Greenland. We explore the intricate associations among host and parasite assemblages and identify key issues and gaps in knowledge that emerge in a regime of accelerating environment...

Examination of the nasal botfly (Cephenemyia stimulator, Clark, 1815) in the roe deer (Capreolus capreolus, Linnaeus, 1758), in Hungary

2017

We examined roe deer in the southern part of Hungary, in different habitats, in the last two hunting seasons. The subject of the examination was the nasal botfly (Cephenemyia stimulator) larvae in the roe deer. We examined to what extent the larva influences key parameters of the roe deer. We researched the skulls of roe deer and we found the different developmental instar larvae. We collected all possible data about these roe deer: the age, the body weight, the condition, the sex and the trophy (antler) weight in case of the bucks. We analyzed and classified the collected and calculated data and specified the typical indicators of parasitology, e.g. the number of infected roe deer, the proportion of infected roe deer, the number of larvae, the parasitism, the prevalence, the mean intensity.

Vectors and transmission dynamics for Setaria tundra (Filarioidea; Onchocercidae), a parasite of reindeer in Finland

Parasites & Vectors, 2009

Background: Recent studies have revealed expansion by an array of Filarioid nematodes' into the northern boreal region of Finland. The vector-borne nematode, Setaria tundra, caused a serious disease outbreak in the Finnish reindeer population in 2003-05. The main aim of this study was to understand the outbreak dynamics and the rapid expansion of S. tundra in the sub arctic. We describe the vectors of S. tundra, and its development in vectors, for the first time. Finally we discuss the results in the context of the host-parasite ecology of S. tundra in Finland Results: Development of S. tundra to the infective stage occurs in mosquitoes, (genera Aedes and Anopheles). We consider Aedes spp. the most important vectors. The prevalence of S. tundra naturally infected mosquitoes from Finland varied from 0.5 to 2.5%. The rate of development in mosquitoes was temperature-dependent. Infective larvae were present approximately 14 days after a blood meal in mosquitoes maintained at room temperature (mean 21 C), but did not develop in mosquitoes maintained outside for 22 days at a mean temperature of 14.1 C. The third-stage (infective) larvae were elongated (mean length 1411 m (SD 207), and width 28 m (SD 2)). The anterior end was blunt, and bore two liplike structures, the posterior end slight tapering with a prominent terminal papilla. Infective larvae were distributed anteriorly in the insect's body, the highest abundance being 70 larvae in one mosquito. A questionnaire survey revealed that the peak activity of Culicidae in the reindeer herding areas of Finland was from the middle of June to the end of July and that warm summer weather was associated with reindeer flocking behaviour on mosquito-rich wetlands.

Endoparasites in a Norwegian moose (Alces alces) population – Faunal diversity, abundance and body condition

International Journal for Parasitology: Parasites and Wildlife, 2015

Many health surveillance programs for wild cervids do not include routine parasite screening despite evidence that gastrointestinal parasites can affect wildlife population dynamics by influencing host fecundity and survival. Slaughter weights of moose in some regions of Norway have been decreasing over recent decades but any role of parasites has not yet been considered. We investigated parasite faunal diversity of moose in Hedmark, SE Norway, by faecal analysis and identification of adult abomasal and caecal nematodes during the autumn hunting season. We related parasite prevalence and abundance to estimates of body condition, gender and age. We identified 11 parasite groups. Moose had high abomasal gastrointestinal nematode (GIN) burdens and all individuals were infected. Ostertagia antipini and Spiculopteragia alcis were the most prevalent abomasal GINs identified. O. leptospicularis and Telodorsagia circumcincta were also identified in the abomasa while a range of other GIN and Moniezia sp. eggs, and coccidia, Dictyocaulus sp. and Protostrongylid larvae were found in faeces.