Mortality of bats at wind turbines links to nocturnal insect migration?

This note is based on a literature search and a recent review of bat mortality data from wind farms in Europe (published elsewhere). We suggest that mortality of bats at wind turbines may be linked to high-altitude feeding on migrating insects that accumulate at the turbine towers. Modern wind turbines seem to reach high enough into the airspace to interfere with the migratory movements of insects. The hypothesis is consistent with recent observations of bats at wind turbines. It is supported by the observation that mortality of bats at wind turbines is highly seasonal (August–September) and typically peaks during nights with weather conditions known to trigger large-scale migratory movements of insects (and songbirds). We also discuss other current hypotheses concerning the mortality of bats at wind turbines.     

Light dependent shift in the anti-predator response of a pyralid moth

Male small china-mark moth Cataclysta lemnata (Pyralidae) swarming over shallow water show a flight activity that peaks during the afternoon but which sometimes is extended into the night. We exposed wild, naturally flying C. lemnata to simulated predator attacks consisting of a) bursts of ultrasound (26 kHz, simulating a bat) and b) a thrown stick (rapid movement, simulating a small bird), during day and night, respectively. We thus investigated the possibility that these moths are able to switch between defensive strategies as the predator regime shifts from insectivorous birds to bats in the evening. The defensive response differed qualitatively between day and night, as expected, but it was independent of the kind of stimulus. We thus demonstrate a previously unknown flexibility in the defensive strategy of moths.     

Use of lamplit roads by foraging bats in southern England

Roads illuminated by white streetlamps attracted three times more foraging bats (mostly Pipistrellus pipistrellus ) than did roads lit by orange streetlamps or unlit roads (3.2, 1.2 and 0.7 bat passes/km, respectively). More insects flew around white lamps than around orange lamps (mean 0.67 and 0.083 insects per lamp, respectively). The mean number of bat passes recorded in any 1-km section of road was positively correlated to the number of white streetlamps along the section, and also, independently, to the amount of trees and hedgerows. Bat activity was not related to the number of houses along the road, ambient temperature or cloud cover. The attractive effect of the lamps on the bats was diminished in windy weather.     

The G428A Nonsense Mutation in FUT2 Provides Strong but Not Absolute Protection against Symptomatic GII.4 Norovirus Infection

In November 2004, 116 individuals in an elderly nursing home in El Grao de Castellón, Spain were symptomatically infected with genogroup II.4 (GII.4) norovirus. The global attack rate was 54.2%. Genotyping of 34 symptomatic individuals regarding the FUT2 gene revealed that one patient was, surprisingly, a non-secretor, hence indicating secretor-independent infection. Lewis genotyping revealed that Lewis-positive and negative individuals were susceptible to symptomatic norovirus infection indicating that Lewis status did not predict susceptibility. Saliva based ELISA assays were used to determine binding of the outbreak virus to saliva samples. Saliva from a secretor-negative individual bound the authentic outbreak GII.4 Valencia/2004/Es virus, but did not in contrast to secretor-positive saliva bind VLP of other strains including the GII.4 Dijon strain. Amino acid comparison of antigenic A and B sites located on the external loops of the P2 domain revealed distinct differences between the Valencia/2004/Es and Dijon strains. All three aa in each antigenic site as well as 10/11 recently identified evolutionary hot spots, were unique in the Valencia/2004/Es strain compared to the Dijon strain. To the best of our knowledge, this is the first example of symptomatic GII.4 norovirus infection of a Le^a+b− individual homozygous for the G428A nonsense mutation in FUT2. Taken together, our study provides new insights into the host genetic susceptibility to norovirus infections and evolution of the globally dominating GII.4 viruses.     

Flight and thermoregulation in moths were shaped by predation from bats

Most larger nocturnal moths ("macrolepidoptera") are equipped with ultrasonic tympanic organs (ears), which give them a considerable survival advantage in encounters with echolocating bats. However, 4.2% of the Scandinavian species lack such organs, and are presumably deaf. Our results show that the earless species are larger and have higher wing loadings than the tympanate forms. They also fly with higher body temperatures. They are thus adapted for fast and erratic flight, and may represent an alternative evolutionary pathway to efficient bat defence, but one that is energetically more demanding. We suggest that the tympanic organs in nocturnal moths were key innovations that "released" their bearers from the energetic constraints imposed by a high flight body temperature, necessary to avoid bats, and probably set the stage for subsequent adaptive radiation of slow flying forms.     

Feeding Territoriality in Female Northern Bats,Eptesicus nilssoni

A nursing colony of 26 Northern bats was studied in South-Central Sweden. The foraging behaviour is described with emphasis on social interactions on feeding grounds. The bats foraged in small feeding territories used night after night. The reproducing females defended feeding territories against other colony members as well as non-members by means of aggressive chases and vocalizations. A linear dominance order occurred among the females that regularly visited a feeding site. Intrusions into already occupied feeding sites resulted in territorial conflicts (47 %), passive departure by one or both opponents (43%) or mutual acceptance (11%). Conflicts occurred throughout the summer, but became less frequent in July when insect abundance increased.     

Food habits of northern (Eptesicus nilssoni) and brown long-eared (Plecotus auritus) bats in Sweden

Food habits of sympatric northern and brown long-eared bats were examined by analysis of droppings collected in six maternity roosts of each species. Relatively large, nocturnal flying insects such as moths (Lepidoptera), June-beetles (Coleoptera: Scarabaeidae), crane-flies (Diptera: Tipulidae) and caddis-flies (Trichoptera), were eaten by both bat species, representing 47% (by volume) of the northern and 57% of the long-eared bat's diet. Small dipterans were important food items for the northern bat (47% of the diet) but not for the long-eared bat, which instead consumed large amounts of diurnal or predominantly non-flying taxa such as blow-flies (Diptera: Calliphoridae), earwigs (Dermaptera), spiders (Araneae) and harvestmen (Opiliones) (40% of the diet). The difference in food selection by the two species is probably due to the different foraging strategies used.     

Norwalk virus-like particles bind specifically to A,H and difucosylated Lewis but not to B histo-blood group active glycosphingolipids

Noroviruses and norovirus virus-like particles (VLPs) exhibit strain specific patterns in their binding to ABH and Lewis histo-blood group antigens. In this study we demonstrate for the first time specific binding of Norwalk virus VLPs to type 1 and type 2 chain glycosphingolipids (GSLs) carrying ABH and Lewis antigens. N-succinimidyl-3-tributylstannyl benzoate (ATE) was precursor labeled with ¹²⁵I and then conjugated to VLPs. The ¹²⁵I-VLPs were used in GSL thin-layer chromatogram binding assays and displayed binding to H type 1, Lewis b, A type 1, A Lewis b GSLs but no binding to B type 1 or B Lewis b GSLs. For the type 2 chain GSLs the Norwalk VLPs bound to H type 2, Lewis y, A type 2 and A Lewis y. In addition, the VLPs bound to several complex GSLs from blood group O and A, but not from blood group B red blood cells.     

A recombinant vaccine effectively induces c5a-specific neutralizing antibodies and prevents arthritis

Objectives

To develop and validate a recombinant vaccine to attenuate inflammation in arthritis by sustained neutralization of the anaphylatoxin C5a.

Methods

We constructed and expressed fusion protein of C5a and maltose binding protein. Efficacy of specific C5a neutralization was tested using the fusion protein as vaccine in three different arthritis mouse models: collagen induced arthritis (CIA), chronic relapsing CIA and collagen antibody induced arthritis (CAIA). Levels of anti-C5a antibodies and anti-collagen type II were measured by ELISA. C5a neutralization assay was done using a rat basophilic leukemia cell-line transfected with the human C5aR. Complement activity was determined using a hemolytic assay and joint morphology was assessed by histology.

Results

Vaccination of mice with MBP-C5a led to significant reduction of arthritis incidence and severity but not anti-collagen antibody synthesis. Histology of the MBP-C5a and control (MBP or PBS) vaccinated mice paws confirmed the vaccination effect. Sera from the vaccinated mice developed C5a-specific neutralizing antibodies, however C5 activation and formation of the membrane attack complex by C5b were not significantly altered.

Conclusions

Exploitation of host immune response to generate sustained C5a neutralizing antibodies without significantly compromising C5/C5b activity is a useful strategy for developing an effective vaccine for antibody mediated and C5a dependent inflammatory diseases. Further developing of such a therapeutic vaccine would be more optimal and cost effective to attenuate inflammation without affecting host immunity.