Attraction and antennal response of the common wasp,Vespula vulgaris (L.), to selected synthetic chemicals in New Zealand beech forests

BACKGROUND: The common wasp, Vespula vulgaris (L.), and the German wasp, Vespula germanica (F.), are significant problems in New Zealand beech forests (Nothofagus spp.), adversely affecting native birds and invertebrate biodiversity. This work was undertaken to develop synthetic attractants for these species to enable more efficient monitoring and management. RESULTS: Seven known wasp attractants (acetic acid, butyl butyrate, isobutanol, heptyl butyrate, octyl butyrate and 2,4‐hexadienyl butyrate) were field tested, and only heptyl butyrate and octyl butyrate attracted significantly higher numbers of wasps than a non‐baited trap. Accordingly, a series of straight‐chain esters from methyl to decyl butyrate were prepared and field tested for attraction of social wasps. Peak biological activity occurred with hexyl butyrate, heptyl butyrate, octyl butyrate and nonyl butyrate. Polyethylene bags emitting approximately 18.4–22.6 mg day^?1 of heptyl butyrate were more attractive than polyethylene bags emitting approximately 14.7–16.8 mg day^?1 of heptyl butyrate in the field. Electroantennogram (EAG) studies indicated that queens and workers of V. vulgaris had olfactory receptor neurons responding to various aliphatic butyrates. CONCLUSION: These results are the first to be reported on the EAG response and the attraction of social wasps to synthetic chemicals in New Zealand beech forests and will enable monitoring of social wasp activity in beech forests. Copyright © 2009 Society of Chemical Industry     

Detection of pigeon circovirus by polymerase chain reaction

Pigeon circovirus was identified by polymerase chain reaction (PCR) in young pigeons belonging to 12 different lofts. Viral DNA was extracted from formalin-fed, paraffin-imbedded tissues containing primarily bursa and occasionally liver and spleen with a commercial kit. PCR primers were selected from a published sequence for columbid circovirus and evaluated in a PCR assay. The histopathologic examination of various tissues revealed basophilic globular intracytoplasmic inclusions in the mononuclear cells of the bursa of Fabricius and occasionally in the spleen characteristic for a circovirus. Transmission electron microscopy of a few bursas of Fabricius revealed virus particles measuring 18-21 nm. All the samples were negative by PCR for psittacine beak and feather disease (PBFD) virus and chicken infectious anemia virus. The primers for both pigeon circovirus and PBFD virus did not react in PCR with the chicken anemia virus DNA. Most of the circovirus-infected pigeons had concurrent infections of Escherichia coli, Salmonella, Pasteurella, Aspergillus, candidiasis, nematodiasis, or capillariasis.     

Experiments to determine the fate of dead birds at sea

This paper describes three experiments aimed at determining the proportion of dead birds at sea which come ashore and are found by members of the public, and discusses the results in relation to wind velocities. From 11% to 58% of the ringed (Larus spp.) corpses thrown into the Irish Sea between Liverpool and the Isle of Man on three occassions in 1973 and early 1974 were recovered. There were large differences between experiments in the timing of the recoveries, although half usually occurred within 11–14 days of dropping. The resultant wind velocities during the time the first bodies recovered from each experiment were at sea were calculated. Comparison of the observed and expected tracks of these bodies confirmed that the wind was the main factor influencing the direction of drift. Gull corpses drifted at a minimum of 2·55±0·93% of the wind speed, although there was much variation and some travelled at over 4% windspeed. With a few exceptions, the observed distribution of recoveries could be broadley predicted by wind vector analysis. The amount of onshore wind when the bodies had reached coastal waters was not related to the subsequent recovery rates. Further experiments are necessary if some of our findings are to be explained and examination of the effect of tidal cycles on the beaching of corpses would also be of value.     

Analysis of 2-methylisoborneol and geosmin in catfish by microwave distillation--solid-phase microextraction

The semivolatile cyclic alcohols 2-methylisoborneol (MIB) and geosmin (GSM) impart muddy or musty flavors to water and food products. A rapid quantitative analytical technique has been developed whereby microwave distillation is used to remove the volatile organic compounds from a lipophilic matrix into an aqueous matrix. Solid-phase microextraction (MD-SPME) is then used to extract and concentrate the analytes, which are then desorbed in the injection port of a gas chromatograph/mass spectrometer (GC/MS) for analysis. Limits of detection are 0.01 microg/kg and limits of quantification are 0.1 microg/kg. MD-SPME is comparable in precision, requires no solvents, and is faster than current methods of analysis. This methodology allows detection of MIB and GSM at concentrations below human sensory thresholds in fish tissue.     

Public health education at the University of California, Davis: past, present, and future programs

This article reviews the history of public-health education at the University of California, Davis, from the inception of the Master of Preventive Veterinary Medicine Program in the School of Veterinary Medicine through the creation of the Master of Public Health Program offered jointly by the Schools of Medicine and Veterinary Medicine. The long history of collaborative teaching and research between the schools, as well as the university's close proximity to and relationship with numerous university-affiliated and state public-health agencies, has created remarkable opportunities for novel and creative public-health education. The university is already anticipating the approval of a School of Public Health on its campus, which will create even more educational opportunities in both human and veterinary public-health disciplines. Given the projected shortfall of veterinarians entering such fields, the opportunity of a novel Doctor of Public Health degree program specifically suited to the needs of veterinary medicine is also discussed as a means of addressing this shortage.     

Microbial C and N dynamics during mesophilic and thermophilic incubations of ryegrass

Laboratory studies were conducted to determine C and N dynamics during the decomposition of ryegrass straw under mesophilic and thermophilic conditions. A K_C of 0.61 was developed for the chloroform-fumigation extraction method to estimate microbial biomass C. These estimates showed that the C and N requirement of the thermophilic biomass was approximately 50% of the mesophilic biomass. There was no relationship between chloroform-fumigation microbial biomass estimates and plating of microorganisms from straw on specific media. Mineralized C was measured as 185 and 210 g kg^-1 straw in the 25°C and 50°C treatments, respectively. The efficiency of microbial substrate use, on a total straw basis, was 34 and 28% in the 25°C and 50°C incubations, respectively. The level of soluble C declined more slowly than total C mineralization at both temperatures, indicating that a portion of the labile C was not readily biodegradable. The addition of N decreased the rate of C mineralization at both temperatures. The reduced N requirement of the thermophiles explains why rapid degradation of the high C:N residue occurred without additional N or the need for the addition of a low C:N ratio substrate. Additional inoculum did not affect the decomposition process. We conclude that the promotion of thermophilic biomass activities, through composting for example, may prove useful in upgrading agricultural wastes for introduction into sustainable cropping systems.     

A critical role for eosinophils in allergic airways remodeling

Features of chronic asthma include airway hyperresponsiveness, inflammatory infiltrates, and structural changes in the airways, termed remodeling. The contribution of eosinophils, cells associated with asthma and allergy, remains to be established. We show that in mice with a total ablation of the eosinophil lineage, increases in airway hyperresponsiveness and mucus secretion were similar to those observed in wild-type mice, but eosinophil-deficient mice were significantly protected from peribronchiolar collagen deposition and increases in airway smooth muscle. These data suggest that eosinophils contribute substantially to airway remodeling but are not obligatory for allergen-induced lung dysfunction, and support an important role for eosinophil-targeted therapies in chronic asthma.     

Aggressive mimicry in photuris fireflies: signal repertoires by femmes fatales

Females of Photuris versicolor prey on males of other species by mimicking the flash responses of the prey's own females. They adjust their responses according to the male pattern, and attract males of four species with distinctively different flashed responses. The capabilities of the firefly brain are more complex than previously suspected. The mimicry is quite effective, and females seldom answered more than ten males without catching one.