The Acanthocephalan Parasites of Eider Ducks

Because of their wide geographical distribution through arctic and subarctic regions of the northern hemisphere, the eider ducks offer some unusual opportunities for the study .of distribution and hostrelations of their parasites. When the Acanthocephala from eider ducks were first studied, the fauna of each continent was regarded as distinct, because it had been reasonably well established that the majority of species of these parasites encounter~d in the United States were distinct from those found in central Europe. This belief failed to take into account the fact that in the arctic the usual distributional bartl:ers to both the definitive and the intermediate hosts are lacking. Recent studies -in northern Europe, especially by Lundstrom (1941, 1942), and Dew collections. on the American continent have added significantly to an understanding, of .:this fauna. The new evidencesmake it seem apparent that for water\u27 birds of the arctic region the acanthocephalan parasites are very widely distrilmted -geographically. This statement does not contradict the generalization that migratory birds have little influence on inter-continental distribution of acanthocephalan parasites. It seems more probable that suitable intermediate hosts for Acanthocephala are widely dispersed in the arctic and subarctic regions and that local bird populations, even though they may have undergone subspecific or specific differentiation, are by food habits and habitat exposed to infection by identical species of parasites on the two continents. This condition of birds under ecologically similar conditions is a direct parallel to that described for fishes of the same regions where numerous species on the two continents serve as definitive hosts for Neoechinorhynchus rutili (Mueller) as demonstrated by Van Cleave and Lynch (1950)

The Acanthocephalan Parasites of Eider Ducks

Because of their wide geographical distribution through arctic and subarctic regions of the northern hemisphere, the eider ducks offer some unusual opportunities for the study .of distribution and hostrelations of their parasites. When the Acanthocephala from eider ducks were first studied, the fauna of each continent was regarded as distinct, because it had been reasonably well established that the majority of species of these parasites encounter~d in the United States were distinct from those found in central Europe. This belief failed to take into account the fact that in the arctic the usual distributional bartl:ers to both the definitive and the intermediate hosts are lacking. Recent studies -in northern Europe, especially by Lundstrom (1941, 1942), and Dew collections. on the American continent have added significantly to an understanding, of .:this fauna. The new evidencesmake it seem apparent that for water\u27 birds of the arctic region the acanthocephalan parasites are very widely distrilmted -geographically. This statement does not contradict the generalization that migratory birds have little influence on inter-continental distribution of acanthocephalan parasites. It seems more probable that suitable intermediate hosts for Acanthocephala are widely dispersed in the arctic and subarctic regions and that local bird populations, even though they may have undergone subspecific or specific differentiation, are by food habits and habitat exposed to infection by identical species of parasites on the two continents. This condition of birds under ecologically similar conditions is a direct parallel to that described for fishes of the same regions where numerous species on the two continents serve as definitive hosts for Neoechinorhynchus rutili (Mueller) as demonstrated by Van Cleave and Lynch (1950)

Occupational lead neurotoxicity: Improvement in behavioural effects after reduction of exposure.

To evaluate critical exposure levels and the reversibility of lead neurotoxicity a group of lead exposed foundry workers and an unexposed reference population were followed up for three years. During this period, tests designed to monitor neurobehavioural function and lead dose were administered. Evaluations of 160 workers during the first year showed dose dependent decrements in mood, visual/motor performance, memory, and verbal concept formation. Subsequently, an improvement in the hygienic conditions at the plant resulted in striking reductions in blood lead concentrations over the following two years. Attendant improvement in indices of tension (20% reduction), anger (18%), depression (26%), fatigue (27%), and confusion (13%) was observed. Performance on neurobehavioural testing generally correlated best with integrated dose estimates derived from blood lead concentrations measured periodically over the study period; zinc protoporphyrin levels were less well correlated with function. This investigation confirms the importance of compliance with workplace standards designed to lower exposures to ensure that individual blood lead concentrations remain below 50 micrograms/dl

Amino acid changes in the spike protein of feline coronavirus correlate with systemic spread of virus from the intestine and not with feline infectious peritonitis

Recent evidence suggests that a mutation in the spike protein gene of feline coronavirus (FCoV), which results in an amino acid change from methionine to leucine at position 1058, may be associated with feline infectious peritonitis (FIP). Tissue and faecal samples collected post mortem from cats diagnosed with or without FIP were subjected to RNA extraction and quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) to detect FCoV RNA. In cats with FIP, 95% of tissue, and 81% of faecal samples were PCR-positive, as opposed to 22% of tissue, and 60% of faecal samples in cats without FIP. Relative FCoV copy numbers were significantly higher in the cats with FIP, both in tissues (P < 0.001) and faeces (P = 0.02). PCR-positive samples underwent pyrosequencing encompassing position 1058 of the FCoV spike protein. This identified a methionine codon at position 1058, consistent with the shedding of an enteric form of FCoV, in 77% of the faecal samples from cats with FIP, and in 100% of the samples from cats without FIP. In contrast, 91% of the tissue samples from cats with FIP and 89% from cats without FIP had a leucine codon at position 1058, consistent with a systemic form of FCoV. These results suggest that the methionine to leucine substitution at position 1058 in the FCoV spike protein is indicative of systemic spread of FCoV from the intestine, rather than a virus with the potential to cause FIP

Monitoring neurotoxins in industry: development of a neurobehavioral test battery

Huguet Françoise. 104 - Elémens (Les) ou premières instructions de la jeunesse. In: , . Les Livres pour l'Enfance et la Jeunesse de Gutenberg à Guizot. Les collections de la Bibliothèque de l'Institut National de Recherche Pédagogique. Paris : Institut national de recherche pédagogique, 1997. p. 57. (Bibliothèque de l'Histoire de l'Education, 16

Renewing the Exploration Approach for Mid-Enthalpy Systems: Examples from Northern England and Scotland

After a promising start in the 1970s and 80s, the UK rather fell behind other countries in the search for viable mid-enthalpy geothermal resources. This situation began to turn around in 2004, when the first of three deep geothermal exploration boreholes were drilled in northern England. What distinguished these from earlier drilling in Cornwall was the deliberate search for naturallyhigh permeability associated with major faults, especially those that have undergone strike-slip reactivation during the Cenozoic. Boreholes at Eastgate in the North Pennines targeted buried radiothermal granite, whereas the 1,821m-deep Science Central Borehole in Newcastle upon Tyne targeted a postulated deep sedimentary aquifer (the Fell Sandstones), which were inferred to be connected laterally to the granitic heat source by a major fault (the reactivation of the Iapetus geo-suture). The drilling was in both cases rewarded with impressive heat flows, and in the case of Eastgate with what is believed to be the highest permeability yet found in a deep granite batholith anywhere in the world. In parallel with these developments, a re-assessment was made of the preexisting geothermal heat flow database for the UK, applying newly-standardised correction protocols for palaeoclimatic and topographic distortions, which were found to be particularly marked in Scotland (where only shallow boreholes had been used to establish geothermal gradients in the original 1980s analysis), Similar prospects in northern England (similar to that drilled at Science Central) are now the focus of commercial exploration efforts. Appraisal of fault dispositions relative to the present-day maximum compressive stress azimuth are being used to identify the most promising areas for intersecting fault-related permeability at depth. New geophysical tools – most notably atomic dielectric resonance scanning – are also being appraised for their ability to directly detect features (such as hot brines) which are indicative of localised convection in target fault zones and aquifers

The effect of mixing entire male pigs prior to transport to slaughter on behaviour, welfare and carcass lesions

peer-reviewedData set for article is also provided.Research is needed to validate lesions recorded at meat inspection as indicators of pig welfare on farm. The aims were to determine the influence of mixing pigs on carcass lesions and to establish whether such lesions correlate with pig behaviour and lesions scored on farm. Aggressive and mounting behaviour of pigs in three single sex pens was recorded on Day −5, −2, and −1 relative to slaughter (Day 0). On Day 0 pigs were randomly allocated to 3 treatments (n = 20/group) over 5 replicates: males mixed with females (MF), males mixed with males (MM), and males unmixed (MUM). Aggressive and mounting behaviours were recorded on Day 0 at holding on farm and lairage. Skin/tail lesions were scored according to severity at the farm (Day −1), lairage, and on the carcass (Day 0). Effect of treatment and time on behaviour and lesions were analysed by mixed models. Spearman rank correlations between behaviour and lesion scores and between scores recorded at different stages were determined. In general, MM performed more aggressive behaviour (50.4 ± 10.72) than MUM (20.3 ± 9.55, P < 0.05) and more mounting (30.9 ± 9.99) than MF (11.4 ± 3.76) and MUM (9.8 ± 3.74, P < 0.05). Skin lesion scores increased between farm (Day −1) and lairage (P < 0.001), but this tended to be significant only for MF and MM (P = 0.08). There was no effect of treatment on carcass lesions and no associations were found with fighting/mounting. Mixing entire males prior to slaughter stimulated mounting and aggressive behaviour but did not influence carcass lesion scores. Carcass skin/tail lesions scores were correlated with scores recorded on farm (rskin = 0.21 and rtail = 0.18, P < 0.01) suggesting that information recorded at meat inspection could be used as indicators of pig welfare on farm.This study was part of the PIGWELFIND project funded by the Department of Agriculture, Food and the Marine (DAFM), Ireland

Timing of UHT metamorphism at Mather Peninsula in Rauer Islands: Zircon and monazite U-Th-Pb and rare earth elements chemistry constraints

第6回極域科学シンポジウム[OG] 地圏11月16日（月）　国立極地研究所３階セミナー