Tommi Paakkonen

Seasonal Rhythms of Body Temperature in the Free‐Ranging Raccoon Dog (Nyctereutes procyonoides) with Special Emphasis on Winter Sleep

The raccoon dog (Nyctereutes procyonoides) is the only canid with passive overwintering in areas with cold winters, but the depth and rhythmicity of wintertime hypothermia in the wild raccoon dog are unknown. To study the seasonal rhythms of body temperature (Tb), seven free‐ranging animals were captured and implanted with intra‐abdominal Tb loggers and radio‐tracked during years 2004–2006. The average size of the home ranges was 306±26 ha, and the average 24 h Tb was 38.0±<0.01°C during the snow‐free period (May–November). The highest and lowest Tb were usually recorded around midnight (21∶00–02∶00 h) and between 05∶00–11∶00 h, respectively, and the range of the 24 h oscillations was 1.2±0.01°C. The animals lost approximately 43±6% of body mass in winter (December–April), when the average size of the home ranges was 372±108 ha. During the 2–9‐wk periods of passivity in January–March, the average 24 h Tb decreased by 1.4–2.1°C compared to the snow‐free period. The raccoon dogs were hypothermic for 5 h in the morning (06∶00–11∶00 h), whereas the highest Tb values were recorded between 16∶00–23∶00 h. The range of the 24 h oscillations increased by approximately 0.6°C, and the rhythmicity was more pronounced than in the snow‐free period. The ambient temperature and depth of snow cover were important determinants of the seasonal Tb rhythms. The overwintering strategy of the raccoon dog resembled the patterns of winter sleep in bears and badgers, but the wintertime passivity of the species was more intermittent and the decrease in the Tb less pronounced.

Freezing tolerance and low molecular weight cryoprotectants in an invasive parasitic fly, the deer ked (Lipoptena cervi)

Insect cold hardiness is often mediated by low molecular weight cryoprotectants, such as sugars, polyols, and amino acids (AA). While many free-living northern insects must cope with extended periods of freezing ambient temperatures (Ta), the ectoparasitic deer ked Lipoptena cervi imago can encounter subfreezing Ta only during a short autumnal period between hatching and host location. Subsequently, it benefits from the body temperature of the cervid host for survival in winter. This study investigated the cold tolerance of the species by determining its lower lethal temperature (100% mortality, LLT100) during faster and slower cold acclimation, by determining the supercooling point (SCP) and by measuring the concentrations of potential low molecular weight cryoprotectants. The LLT100 of the deer ked was approximately -16 ° C, which would enable it to survive freezing nighttime Ta not only in its current area of distribution but also further north. The SCP was -7.8 ° C, clearly higher than the LLT100 , indicating that the deer ked displays freezing tolerance. The concentrations of free AA, especially nonessential AA, were higher in the cold-acclimated deer keds similar to several other insects. The concentrations of proline increased together with γ-aminobutyrate, arginine, asparagine, cystine, glutamate, glutamine, hydroxylysine, sarcosine, serine, and taurine. AA could be hypothesized to act as cryoprotectants by, e.g., protecting enzymes and lipid membranes from damage caused by cold.

Threat of An Invasive Parasitic Fly, the Deer Ked (Lipoptena cervi), to the Reindeer (Rangifer Tarandus Tarandus): Experimental Infection and Treatment

Range expansion of ectoparasites can cause parasites to attack new host species. In these cases it is important for the parasite to be able to adapt to the new environment and to reproduce on the host. For the host, it is crucial to hinder successfully the development of long-lasting parasitic relationship. The deer ked (Lipoptena cervi) is a novel ectoparasite for northern cervids. We investigated if the deer ked can use the reindeer (Rangifer tarandus) as a host and, if it can, whether antiparasitic treatment against this parasite would be available. Three groups of reindeer were monitored: two groups of 6 reindeer were infected with 300 flies per each individual; a control group comprised 6 animals. One of the infected groups was treated with subcutaneous ivermectin. At the end of the experiment the infestation rate of the infected animals was low. The reindeer in the non-treated group had both live and dead deer keds and also a single pupa while the ivermectin-treated reindeer had only dead deer keds. As some deer keds survived and reproduced, the deer ked can potentially use the reindeer as a host but antiparasitic treatment may be effective against this parasite.

Molecular detection of Bartonella spp. in deer ked pupae, adult keds and moose blood in Finland

The deer ked (Lipoptena cervi) is a haematophagous ectoparasite of cervids that harbours haemotrophic Bartonella. A prerequisite for the vector competence of the deer ked is the vertical transmission of the pathogen from the mother to its progeny and transstadial transmission from pupa to winged adult. We screened 1154 pupae and 59 pools of winged adult deer keds from different areas in Finland for Bartonella DNA using PCR. Altogether 13 pupa samples and one winged adult deer ked were positive for the presence of Bartonella DNA. The amplified sequences were closely related to either B. schoenbuchensis or B. bovis. The same lineages were identified in eight blood samples collected from free-ranging moose. This is the first demonstration of Bartonella spp. DNA in a winged adult deer ked and, thus, evidence for potential transstadial transmission of Bartonella spp. in the species.

Experimental infection of the deer ked (Lipoptena cervi) has no negative effects on the physiology of the captive reindeer (Rangifer tarandus tarandus)

The deer ked (Lipoptena cervi) is a haematophagous parasitic fly of cervids that spread to Finland in the early 1960s. Presently its northern distribution limit lies at approximately 65°N and it is gradually spreading northwards. In Finland the principal host species has been the moose (Alces alces), but the deer ked is about to establish contact with another potential host, the semi-domesticated reindeer (Rangifer tarandus tarandus) causing possible threats to reindeer health and management. The aim of this study was to investigate if the deer ked would have an influence on the welfare of the reindeer. Eighteen adult reindeer were divided into three experimental groups: the control group and two infected groups with 300 deer keds per reindeer introduced in August-September. One of the infected groups was treated with subcutaneous ivermectin in November. To gather comprehensive data on potential health hazards caused by the deer ked a wide array of physiological variables was measured during and at the end of the experiment in December. The keds caused no clear changes in the complete blood count, plasma clinical chemistry, amino acids, endocrinology, energy stores, enzyme activities or tissue fatty acid profiles of the host. The haematological, clinical chemical and endocrinological values displayed changes that could be related to the seasonal physiological adaptations of the species. In conclusion, at the duration and intensity of infection that were employed, the effects of the deer ked on the measured physiological variables of the reindeer were insignificant.

The effects of an abundant ectoparasite, the deer ked (Lipoptena cervi), on the health of moose (Alces alces) in Finland

The deer ked (Lipoptena cervi, Diptera, Hippoboscidae) is a haematophagous parasitic fly of the moose (Alces alces) and other cervids, and it is very common in southern and central parts of Finland. The aim of this study was to determine how the intensive parasitism caused by the deer ked affects the health and welfare of the moose. Moose blood samples (n = 78) were collected from deer ked-infested and ked-free regions at 62–68° N and analysed for haematology and clinical chemistry. In addition, tissue samples of moose (n = 23) were collected from a deer ked-infested region at 62° N to determine how the parasite load correlates to several physiological variables of the host. The differences in the blood and plasma values between the deer ked-free and ked-infested animals were minor. In the infested regions, the moose had higher mean corpuscular haemoglobin concentrations unlikely to have been caused by the parasitism. The intensities of deer keds had no consistent correlations with the values of plasma clinical chemistry, endocrinology, amino acids, tissue enzyme activities or body energy stores. However, the hepatic percentages of several individual n-3 polyunsaturated fatty acids (PUFA) and the n-3 PUFA sum correlated inversely with the intensity and density of deer keds. Although a wide array of physiological variables was determined, only minor effects caused by the heavy deer ked parasitism could be detected, suggesting that the moose might tolerate this parasite relatively well.

Life stage-related differences in fatty acid composition of an obligate ectoparasite, the deer ked (Lipoptena cervi)—Influence of blood meals and gender

Metamorphosis and diet often influence fatty acid (FA) signatures (FAS) of insects. We investigated FAS in a hematophagous ectoparasite, the deer ked (Lipoptena cervi). Deer keds shed their wings upon attachment on the host and, thus, the FAS of an individual blood-fed imago/pupa in the fur of its host can be traced back to the blood FA profile of a single moose (Alces alces). Host blood and different life stages of deer keds were investigated for FA by gas chromatography. The FAS of life stages resembled each other more closely than the diet. Blood meals modified the FAS of both sexes but the FAS of the blood-fed females were closer to those of the prepupae/pupae. The parasitizing males had higher proportions of major saturated FA (SFA) and polyunsaturated FA (PUFA) than the females, which contained more monounsaturated FA (MUFA) with higher ratios of n-3/n-6 PUFA and unsaturated FA (UFA)/SFA. The proportions of 16:1n-7 were <1% in the blood but 18% (males) and 29% (females) in the blood-fed keds. Allocation of lipids to offspring by the females and possible accumulation of PUFA in male reproductive organs may have induced these sex-related differences. MUFA percentages and UFA/SFA ratios increased while SFA and many PUFA decreased from the reproducing females to the pupae. The diapausing pupae displayed lowered n-3/n-6 PUFA ratios and could have mobilized 16:0 and 18:3n-3 for the most fundamental metabolic processes. In conclusion, FAS are modified through the life stages of the deer ked possibly due to their different FA requirements.

Fatty acid modifications during autumnal cold-hardening in an obligatory ectoparasite, the deer ked (Lipoptena cervi)

Poikilothermic organisms often modify their tissue fatty acids (FA) in response to cold exposure by increased unsaturation. In insects, this has been found to be accompanied by increases in the activities or mRNA expression of desaturase enzymes. In the present study, the FA composition of an obligatory ectoparasite, the deer ked (Lipoptena cervi), was analyzed in August-November. In addition to studying the general FA profile of the species, the possible contribution of FA to autumnal cold-hardening was examined. The FA composition of the deer ked imago was relatively similar to previously studied dipteran species, with high percentages of monounsaturated FA (especially 18:1n-9 and 16:1n-7) and 16:0. The individuals caught later in autumn had significantly higher values for the ratio of unsaturated to saturated FA and, regarding individual FA, the percentages of 18:1n-9, 18:2n-6, 18:3n-3, 20:4n-6 and 22:6n-3 were higher but those of 16:0 and 16:1n-7 lower than in August. Potential selective use of particular FA for energy could not account for the large increase in the levels of polyunsaturated FA (PUFA). The observed increased degree of FA unsaturation may have resulted from cold-induced desaturation, as observed previously in other species, or increased survival of the keds with relatively large PUFA contents. The PUFA with low melting points probably allow lipid membranes to maintain sufficient fluidity required to maintain protein functions at low ambient temperatures.

Salt licks do not increase local densities of the deer ked, Lipoptena cervi, an abundant ectoparasite of cervids

The deer ked, Lipoptena cervi (Diptera: Hippoboscidae), is a common ectoparasite of the moose, Alces alces (Artiodactyla: Cervidae). Salt licks are widely used to manipulate moose movements to prevent damage to saplings and traffic accidents. They may cause moose to gather in small areas, which could create aggregates of deer ked pupae as the parasite is a short‐distance flyer and its dispersion depends on its hosts. We investigated whether the population density of flying deer keds could be influenced by manipulating salt licks and how environmental variables affect parasite density. Densities were estimated in 40 experimental sites with four treatments (no salt licks, introduced salt licks, removed salt licks, permanent salt licks) in September during 2007–2010. Forest edges, mixed forests on mineral soil and coniferous forests on peat soil were the habitats with high numbers of parasites. The manipulation of salt licks seemed to be ineffective in reducing the density of deer keds as the only factor to show statistical significance with parasite numbers in the mixed‐model analysis was year of determination. Annual deer ked densities correlated with the abundance of moose in the region. Moreover, high spring and summer temperatures seemed to increase the numbers of flying imagos.

Abortion debates in Finland and the Republic of Ireland: textual analysis of experiential thinking and argumentation in parliamentary and layperson discussions

BackgroundThe ethical discussion about abortion has been polarized in Finland and the Republic of Ireland, two European countries with very different abortion legislation (liberal vs. highly restrictive). The aim of the present study was to analyze experiential thinking patterns and argumentative strategies in political and layperson debates regarding induced abortion.MethodsThe content of Finnish and Irish texts (n = 493), consisting of transcripts of parliamentary debates and online texts, such as blogs, was analyzed systematically. The texts were investigated for the aspects of experiential thinking, for selected argumentative moves and for any differences in the prevalence of these features between countries or between political vs. layperson debates.ResultsThe Finnish and Irish discussions about induced abortion relied heavily on experiential thinking patterns and emotionally laden arguments instead of objective research data. This was evident in the very high prevalence of testimonials, narratives, loaded language and appeals to emotion in both political and layperson debates regardless of the country or the debaters position on abortion issue. Research data that did not support the position of the debater were relatively often omitted by confirmation bias. The Irish debaters appealed to popularity more often than the Finnish ones, while magical/religious thinking was mainly observed in the Finnish layperson discussion. The national history and the prevailing cultural and religious atmosphere of the two countries could explain these differences.ConclusionsThe abortion debate mostly reinforces the opinions of ones peer group rather than convinces the opposite party to change their position. The stalemate and continuation of the same arguments being repeated could be associated with experiential thinking and emotional argumentative strategies in both political and layperson debates.