Global changes such as deforestation, climate change, and invasive species have the potential to greatly alter zoonotic disease systems through impacts on biodiversity. This study examined the impact of the invasive pathogen that causes sudden oak death (SOD) on the ecology of Lyme disease in California. The Lyme disease bacterium, Borrelia burgdorferi, is maintained in the far western United S...

Borrelia burgdorferi, the Lyme disease pathogen, dramatically alters its protein profile when it is transmitted between ticks and mammals. Several differentially expressed proteins have been shown to be critical for the enzootic cycle of B. burgdorferi. In this study, we demonstrated that expression of the surface lipoprotein-encoding gene bba07 is induced by an elevated temperature and a reduc...

Because the nymphal stages of L. serrata isolated from different animals have different strains, it was assumed that their somatic proteins would be different. The present study was conducted to evaluate and characterise the somatic proteins of L. serrata nymphs, isolated from goats and cattle mesenteric lymph nodes. Nymphs were collected from the infected mesenteric lymph nodes of slaughtered ...

Risk of exposure to Lyme disease is a function of the local abundance of nymphal Ixodes ticks that are infected with the etiological agent, the spirochete Borrelia burgdorferi. We monitored abundance of white-footed mice (the principal B. burgdorferi reservoir in the eastern and central United States) and acorns (a critical food resource for mice), and Ixodes scapularis ticks, as well as ambien...

Some biological and population parameters of Ronderosia bergi (Stål) (Orthoptera: Acrididae: Melanoplinae) were estimated by monitoring five cohorts of the first generation (F1) of individuals born in captivity from grasshoppers collected in the South of Misiones province, northeastern Argentina, and held under controlled conditions (30 degrees C, 14:10 L:D, 40% RH). The mean embryonic developm...

BACKGROUND The Asian citrus citrus psyllid, Diaphorina citri Kuwayama, transmits a bacterium that causes huanglongbing in citrus. Frequent and repeated use of neurotoxic insecticides against D. citri has resulted in the development of insecticide resistance. We evaluated the effects of the juvenile hormone analog methoprene on egg hatch, nymphal development, adult emergence, reproduction and be...

A large number of coccoid, or oval to spindle-shaped rickettsialike microorganisms are detected intracellularly within the primordial ovaries of all examined molting larvae and nymphs, descendants of a female Ixodes ricinus collected in a forest near Neuchâtel, Switzerland, and within all molting nymphal I. ricinus captured as starved ticks in the same area. The morphology of the microor­ ganis...

Ecdysteroidogenesis is essential for arthropod development and reproduction. Although the importance of ecdysteroids has been demonstrated, there is little information on the sites and enzymes for synthesis of ecdysteroids from Chelicerates. Ecdysteroid functions have been well studied in the soft tick Ornithodoros moubata, making this species an excellent candidate for elucidating ecdysteroido...

Twocommercial formulations ofBeauveria bassiana(Balsamo-Crivelli)Vuilleminwere applied to residential sites in Old Lyme, CT, for the control of nymphs of the blacklegged tick, Ixodes scapularis, in 1999 and 2000. The pyrethroid bifenthrin was applied to other premises for comparison with B. bassiana. A wood chip barrier was installed and maintained at six of the treated properties. In 1999, con...

We found that sexual differentiation of all the nymphal stages of Pycnoscelus indicus (Fabricius) was possible by observing the developmental features of their posterior abdominal segments. Using this observation, the sex of even the 1st stage instar nymph could be determined. The female of the 1st to 6th stage instar nymph possess a V-shaped notch at the middle of the posterior edge of the 9th...