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Adult Ticks (adult + tick)
Selected AbstractsSeasonal dynamics of the brown dog tick, Rhipicephalus sanguineus, on a confined dog population in ItalyMEDICAL AND VETERINARY ENTOMOLOGY, Issue 3 2010V. LORUSSO This study evaluated the seasonal dynamics of Rhipicephalus sanguineus (Latreille) (Acari: Ixodidae) on naturally infested dogs in a private shelter in southern Italy. From March to May 2008, 39 autochthonous mixed-breed young dogs and 10 beagles were enrolled in the study. From March 2008 until March 2009, every 21 ± 2 days, 11 body sites of each dog were checked for ticks. At each follow-up, the number of ticks, their developmental stage, sex and location on the dog's body were recorded. Adult ticks were found throughout the year, but immatures were absent in January and February. The adult tick population increased from July to August, whereas the load of immatures increased in early July and peaked in September, which suggests that R. sanguineus develops one generation per year in this area. The mean number of immature ticks per infested dog was higher than that of adults from March to October 2008. Ears, interdigital areas and armpits were the most frequent attachment sites of adult ticks. At the last follow-up, a total of 2266 ticks were collected and identified as R. sanguineus. The results suggest that R. sanguineus develops one generation per year in the study area, but that it infests dogs in all seasons. This information should be taken into account when planning control programmes against this tick species and the pathogens it transmits. [source] Detection and typing of Borrelia burgdorferi sensu lato genospecies in Ixodes persulcatus ticks in West Siberia, RussiaFEMS MICROBIOLOGY LETTERS, Issue 2 2003Anatoly B Beklemishev Abstract The prevalence of Borrelia burgdorferi sensu lato (s.l.) genospecies in West Siberia as well as in many other regions of Russia remains insufficiently investigated. In the present study a total of 151 adult female ticks Ixodes persulcatus Schulze, collected at three localities in eastern regions of West Siberia, where Lyme disease is endemic, were examined for the presence of the spirochete B. burgdorferi s.l. by polymerase chain reaction targeting the 23S,5S rRNA intergenic spacer regions. Spirochetal DNA was detected in on average 15.2±3.0% of the ticks examined. The infection rate of adult ticks with B. burgdorferi s.l. at various localities ranged from 8.6±3.4% to 29.0±7.6%, being greatest in the northernmost site studied and decreasing southwards. The restriction patterns obtained after MseI digestion of the 23S,5S rRNA intergenic spacer amplicons assigned 23 DNA samples to the following genomic groups: 19 to B. garinii (12 to group NT29 and seven to group 20047T), three to B. afzelii, and one to mixed B. afzelii and B. garinii NT29. We have not detected other genospecies, which were found in ticks in Europe, the Russian Far East and Japan. Thus, the ticks examined were associated only with two genospecies of Borrelia burgdorferi s.l. pathogenic to humans (B. garinii and B. afzelii), and B. garinii was the major genospecies infecting adult I. persulcatus in eastern regions of West Siberia. [source] Molecular characterization of a peroxiredoxin from the hard tick Haemaphysalis longicornisINSECT MOLECULAR BIOLOGY, Issue 2 2001N. Tsuji Abstract Antioxidant enzymes in eukaryotes play an important role in protection against the oxygen radicals generated during aerobic metabolism. Here we report the cloning and characterization of a cDNA encoding the antioxidant enzyme peroxiredoxin from the hard tick Haemaphysalis longicornis (HlPrx). HlPrx is 939 bp long and contains a 101 bp non-translated sequence at the 5, end and a polyadenylation singnal followed by a poly(A) tail at the 3, end. HlPrx encodes a full-length protein with a predicted molecular mass of 26 kDa that possesses one cysteine residue at amino acid 49 that is conserved among Prx proteins of various species. GenBankÔ analysis showed that the deduced amino acid sequence had significant similarity to mammalian and plant Prxs at the amino acid level. A DNA-nicking assay revealed that Escherichia coli,expressed recombinant HlPrx (rHlPrx) inhibited oxidative-nicking of supercoiled plasmid DNA. Two-dimensional immunoblot analysis with mouse antirHlPrx serum showed reaction with a major constituent protein spot in extracts of adult ticks. In addition, immunoblot analysis showed that rHlPrx was immunoreacted with serum from rabbits repeatedly infested with H. longicornis. Localization analysis using mouse antirHlPrx serum revealed that native HlPrx was highly expressed in the salivary gland of the tick. Moreover, Northern blot analysis showed that the level of HlPrx transcripts was increased during blood sucking. The present results indicate that HlPrx may be an important detoxifying enzyme during the normal life span as well as during blood sucking in ticks. [source] Ticks and Lyme borreliosis in an alpine area in northeast ItalyMEDICAL AND VETERINARY ENTOMOLOGY, Issue 3 2010F. NAZZI A 2-year study was conducted in a mountainous area of northeast Italy to evaluate the occurrence and distribution of ticks, as well as to assess the prevalence of the spirochaete Borrelia burgdorferi sensu lato. All ticks collected were Ixodes ricinus L. (Parasitiformes: Ixodidae). In general, most nymphs and adult ticks were collected from April to July. Tick density was highly variable among sites; however, two areas with different infestation levels were recognized. Prevalences of B. burgdorferi s.l. in nymphal stages were rather variable between sites; overall the prevalence of infected nymphs in the whole area was slightly higher than 20%. The prevalence of B. burgdorferi s.l. in nymphs does not seem to be correlated with nymph density. The correlation between the incidence of Lyme borreliosis (reported human cases/1000 inhabitants/year) and Borrelia prevalence in nymphs was not significant, although a significant correlation was found between borreliosis incidence and nymph density. [source] Seasonal dynamics of the brown dog tick, Rhipicephalus sanguineus, on a confined dog population in ItalyMEDICAL AND VETERINARY ENTOMOLOGY, Issue 3 2010V. LORUSSO This study evaluated the seasonal dynamics of Rhipicephalus sanguineus (Latreille) (Acari: Ixodidae) on naturally infested dogs in a private shelter in southern Italy. From March to May 2008, 39 autochthonous mixed-breed young dogs and 10 beagles were enrolled in the study. From March 2008 until March 2009, every 21 ± 2 days, 11 body sites of each dog were checked for ticks. At each follow-up, the number of ticks, their developmental stage, sex and location on the dog's body were recorded. Adult ticks were found throughout the year, but immatures were absent in January and February. The adult tick population increased from July to August, whereas the load of immatures increased in early July and peaked in September, which suggests that R. sanguineus develops one generation per year in this area. The mean number of immature ticks per infested dog was higher than that of adults from March to October 2008. Ears, interdigital areas and armpits were the most frequent attachment sites of adult ticks. At the last follow-up, a total of 2266 ticks were collected and identified as R. sanguineus. The results suggest that R. sanguineus develops one generation per year in the study area, but that it infests dogs in all seasons. This information should be taken into account when planning control programmes against this tick species and the pathogens it transmits. [source] Field and laboratory studies in a Neotropical population of the spinose ear tick, Otobius megniniMEDICAL AND VETERINARY ENTOMOLOGY, Issue 1 2009S. NAVA Abstract One ear of each of five cows on a property close to Dean Funes, province of Córdoba, Argentina, was inspected monthly from December 2004 to November 2006 to determine the presence of Otobius megnini (Dugès) and to ascertain its seasonality. Ticks were collected to study the biological parameters of larvae, nymphs and adult ticks. Groups of nymphs were also maintained at three different photoperiods at 25 °C. The abundance of immature stages was greatest during January,April and August,October in the first and second years of the study, respectively. No larvae successfully moulted. Nymphs weighing < 17 mg also failed to moult, but 89% of heavier nymphs moulted into adults. Nymphs moulting to males weighed less (49.5 ± 16.09 mg) than nymphs moulting to females (98.1 ± 34.08 mg). The pre-moult period was similar for nymphs moulting to either sex and significantly longer (P < 0.01) for female nymphs maintained at 25 °C compared with nymphs kept at 27 °C. No effect of photoperiod on the pre-moult periods of nymphs was detected. Female ticks produced a mean of 7.0 ± 1.94 egg batches after a preoviposition period of 16.4 ± 8.41 days for the first batch. The mean oviposition period was 61 ± 20.8 days and the duration of oviposition for each batch varied from 1 to 6 days. The mean number of eggs per batch was 93.1 ± 87.53. The minimum incubation period for the first egg batch was 13.6 ± 2.77 days. The total number of eggs laid by each female was 651.6 ± 288.90. Parthenogenesis was not observed. The reproductive efficiency index (REI) (number of eggs laid/weight of female in mg) was 5.5 ± 1.26. Pearson's correlations showed a significant direct relationship between the weight of the female and number of eggs laid (P < 0.01) and REI (P < 0.05). Several of the biological values presented above for the tick population from the Neotropical zoogeographic region showed marked differences to equivalent values for O. megnini populations from the U.S.A. (Nearctic) and India (Oriental). Nevertheless, the only two sequences of 16S rDNA deposited in GenBank from ticks originating in Argentina and allegedly in the U.S.A. indicate that they are conspecific (99.8% agreement). We tentatively consider the biological differences among populations of this tick species to represent adaptations for survival at different conditions. [source] Effects of infection of the tick Ornithodoros moubata with African swine fever virusMEDICAL AND VETERINARY ENTOMOLOGY, Issue 4 2000L. Rennie Summary The effects of infection with African swine fever virus (ASFV) on adult and nymphal Ornithodoros moubata Murray (Ixodoidea, Argasidae) ticks were examined. Three groups of ticks were used, an uninfected control group, one group infected with the VIC T90/1 isolate of ASFV and another group infected with the LIV 13/33 isolate of ASFV. Infection with ASFV did not affect the oviposition rates of infected ticks when compared with uninfected ticks. There was no difference between infected and uninfected ticks in progeny hatching rates and first nymphal stage feeding rates. Feeding rates of infected adult ticks were also unaffected. However, a significant increase in mortality rates was observed amongst the adult ticks that fed on an infective bloodmeal compared to ticks fed on an unifected bloodmeal. [source] |