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Within the entomological monitoring program of the German federal ministry of food, agriculture, and user protection (BMELV), at 12 cattle farms in Rhineland-Palatinate and two in Saarland, ultraviolet lamp traps were used to monitor the distribution and seasonal appearance of potential vectors of the bluetongue virus, with special consideration of species of Culicoides. Using the traps during the first seven nights of each month from April 2007 to May 2008, 5,000-120,000 ceratopogonids were caught at different locations, in total about 500,000 and mainly females. Ninety-four percent belonged to the genus Culicoides, and of these, 90% were Culicoides obsoletus s.l., 6% were Culicoides pulicaris s.l., and 4% were other species of this genus. In all traps, the first ceratopogonids were caught in April 2007, the total number peaking in August 2007. After a reduction in September, a lower peak occurred in October. During the whole winter, some ceratopogonids were active. At nearly all locations, the total numbers of C. obsoletus s.l., C. pulicaris s.l., and of other ceratopogonids were significantly correlated with the temperatures, and higher population densities of C. obsoletus s.l. seemed to occur at altitudes of about 300 m above sea level.

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A cDNA encoding a trypsin-like protease from the salivary glands of the haematophagous reduviid Panstrongylus megistus was cloned and sequenced. The deduced protein sequence showed similarities to serine proteases of other hemipterans but with substitutions in the catalytic triad and the substrate binding site. The expression of the gene increased more than sixfold after feeding. Saliva showed the highest proteolytic activity at neutral to slightly basic pH. Substrate and inhibitor profiles and zymography indicated the presence of a trypsin-like protease with preference for Arg and Lys at P1. Using chromatography, a fibrinolytic enzyme was purified whose sequence was identified by tandem mass spectrometry as that encoded by the cDNA.

The outbreak of bluetongue disease in Central Europe necessitates new approaches in the identification of vectors to follow-up changes of populations of species and not of complexes. Since females of species of the complex of Culicoides obsoletus are difficult to be identified according to morphological criteria, we applied a polymerase chain reaction (PCR)-based strategy targeting the mitochondrial cytochrome oxidase subunit I to differentiate between the species Culicoides obsoletus s.s. and Culicoides scoticus. Catches of culicoids obtained from May to November 2007 in an ultraviolet lamp trap at a cattle farm in Rhineland-Palatinate, Southern Germany were surveyed for changes of the abundance of both species. Only in May 2007, the samples contained similar proportions of both species. Afterwards, C. scoticus dominated with up to 88%. Calculating the number of specimens of both species within the total catches of culicoids, the numbers of C. obsoletus s.s. slightly decreased from May to July and increased to a little maximum in August. C. scoticus seemed to have three maxima in this period of time, the strongest one in August, presumably due to different generations and not to climatic conditions. These results indicate that the applied PCR strategy can be used for a detailed analysis of culicoids as basis for the estimation of the transmission risk of the bluetongue virus by different species of the Obsoletus complex.

Antibacterial proteins like lysozyme are important components of the insect non-specific immune response against bacteria. The complementary deoxyribonucleic acid (cDNA) encoding a new lysozyme from Triatoma infestans, named lysozyme2, has been amplified by polymerase chain reaction and the rapid amplification of cDNA ends technique. The gene is expressed in the small intestine of the insect. The deduced protein sequence shows up to 70% similarity to lysozymes from other species. Furthermore, the protein exhibits significant structural concordance to other insect lysozymes. A striking feature of the lysozyme2 protein is the replacement of the conserved amino acid residues of the active site of classical c-type lysozymes, glutamate and aspartate, by valine and tyrosine.

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