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PubMed1992

[Morphologic features, with particular regard to surface ultrastructure, of Docophoroides brevis (Docophoroididae, Mallophaga)].

Bodies of nymphs and adults of Docophoroides brevis (Docophoroididae), parasite of Diomedea exulans, were studied under light and scanning microscopes. Developmental features of nymphs corresponded with similar features of other Philopteroidea. In adults type and distribution of sensillae were similar to other Ischnocera. Structures pointing to parasite's adaptation to holding itself on host's feathers, were distinguished. They were, besides characteristic claws, the mouth apparatus, groups of hooked processes on tibiae of the II and III pairs of legs, and sculpture of roundish fields on the sides of abdomen sternites. In the shape of male's genital apparatus, protruding to the outside of terminal sclerite, structures helping both partners to contact during copulation were discerned.

Animals↗
PubMed2003

[Relative abundance of Amblyomma spp. (Acari: Ixodidae) in bovines (Bos taurus and B. indicus) from Costa Rica].

The research describe the big amount of ticks of the Amblyomma genus, found on bovines through monthly samplings carried out in ten farms in eight ecological zones (EZ) of Costa Rica. Ticks larger than 4 mm were picked up from the right side of the animals during the visit. The study compiled meteorological information for some farms located in the experiment, showing that the most fluctuant variable is rainfall. The most important Amblyomma species found was A. cajennense. Amblyomma nymphs were found only from January to May, which coincides with the lower humidity season in the rain seasonality area; as for it is expected only one generation per year. In the lab work Amblyomma nymphs are kept to measure the moulting season and the surviving time under controlled conditions, but no major differences were found between both sexes. The surviving periods show that it is not possible to do a grazing land handling, in order to control this genus species. Adults of the genus Amblyomma are present through all the year, not showing any specific preference for a season. The research divided the investigation areas in rain seasonability and not-seasonality systems. The highest amount of Amblyomma is found given in the rain seasonality system or of pacific influence. A. maculatum is present only in the EZ of Tropical Humid Forest transition to pre-mountainous. Likewise, Ixodes boliviensis is found in the EZ of low mountainous Very Humid Forest.

Animals↗
PubMedDate not supplied

[Anomalohimalaya lotozkyi sp. n., a new species of ixodid ticks from the Peter the First Range (Ixodoidea, Ixodidae)].

Anomalohimalaya lotozkyi sp. n., the second species of this genus, was found in Tadzhikistan, Peter I ridge, at the height of 2700 m above the sea level in rocky locality with xerophilous vegetation on Alticola argentatus. In June, 1977 there were found larvae and nymphs of the species. After feeding larvae and then nymphs females and males were obtained. All phases of the life cycle differ distinctly from those of the type species An. lama Hoog., Kais. et Mitch., 1970, from Himalayas. The diagnosis of the genus Anomalohimalaya is specified. This genus combines the characters of Haemaphysalis Koch and Rhipicephalus Koch and is of great significance for more precise definition of phylogeny of the subfamily Amblyomminae Banks.

Animals↗
PubMed2004

Prevalence of Borrelia burgdorferi sensu lato genospecies in host-seeking Ixodes ricinus ticks in selected South Bohemian locations (Czech Republic).

In selected localities of Ceské Budĕjovice and Ceský, Krumlov districts, well known by stable high incidence of tick-borne encephalitis (TBE) human cases but with low incidence of Lyme borreliosis, monitoring of Borrelia burgdorferi sensu lato (s.l.) in Ixodes ricinus ticks was performed. Research was also aimed at the spread of I. ricinus to mountain areas of this region (National Park Sumava), as well as at investigating this tick for B. burgdorferi s.l. genospecies and TBE virus infection. Altogether 498 nymphs, 88 females and 11 males of I. ricinus from lower locations and 58 nymphs from mountain locations (760-1080 m above sea level) were tested by polymerase chain reaction. In lower locations total prevalence of Borrelia burgdorferi s.l. in Ixodes ricinus ticks was 35%. Single infection of Borrelia afzelii, B. garinii and B. burgdorferi sensu stricto (s.s.) was found in 59, 50 and 63 ticks, respectively (i.e. in 12.8, 11.2 and 14.1%). Double infection was found in 42 ticks (6.0%) and triple infection in three ticks (0.4%). The high frequency of B. burgdorferi s.s. exceeds the as yet reported occurrence in Central Europe. These circumstances are discussed. In mountain locations B. afzelii was found in five ticks, that including two co-infection with B. garinii, in elevations of 762 m and 1024 m above sea level, respectively. This fact signals a real danger of human infections in a region that was previously deemed to be without risk. Moreover, this region is more and more the target destination of tourist activities. The results also suggest that the penetration of infection can be rapid and formation and establishment of natural focus of Lyme borreliosis might be rather quick.

Animals↗
PubMed2004

Mixed domestic infestation by Rhodnius prolixus Stal, 1859 and Panstrongylus geniculatus Latreille, 1811, vector incrimination, and seroprevalence for Trypanosoma cruzi among inhabitants in El Guamito, Lara State, Venezuela.

Mixed infestation of nymphs and adults of Rhodnius prolixus Stal, 1859 and Panstrongylus geniculatus Latreille, 1811 was detected in 3 (15%) of 20 dwellings in El Guamito, an endemic focus of Chagas disease in Lara State, Venezuela. In one of the houses, both species were positive for Trypanosoma cruzi: 14.3% (R. prolixus) and 20% (P. geniculatus ). The overall infection rate in 143 of 352 R. prolixus was 16.1%. Parasites isolated from R. prolixus were identified as T. cruzi I by random amplified polymorphic DNA analysis. Dot-enzyme-linked immunosorbent assays of 36 R. prolixus showed that 58.3% of the R. prolixus had fed on humans. The gut contents of one fifth-instar nymph of P. geniculatus that was positive for T. cruzi also reacted with anti-human serum. A questionnaire was used to gather data on the demographic and socioeconomic characteristics of the population. An indirect immunofluorescent test, an indirect hemaglutination test, and an ELISA were used to detect the presence of antibodies against T. cruzi in 84 of 86 inhabitants and in 15.5% of people more than 20 years old. The relative risk (RR) of infection was greater in men than in women (RR = 1.61, 95% confidence interval = 0.54-4.80). Of the people more than 15 years old, 36.6% had no formal education. All respondents recognized triatomine bugs, but they did not relate them to Chagas disease transmission. A total of 85.7% of the houses were "ranchos" suitable for the colonization of triatomine bugs. The possible domiciliation of P. geniculatus and the implications of competition with R. prolixus for resources are discussed. Since there is no clear separation of food sources, abiotic factors such as microclimatic variation within houses may be critical to predict the outcome of the process of competition and potential domestication of this generally sylvatic species.

Adolescent↗
PubMedDate not supplied

[Methods for estimating the demographic structure of the taiga tick (Ixodidae) based on results of standard parasitological observations].

A retrospective estimation of the abundance dynamics of the taiga tick Ixodes persulcatus in mixed coniferous and leaf-bearing forests of the Udmurtia Republic in the period 1957-1986 was carried out. A possibility to estimate the absolute number of all stages of I. persulcatus based on relative indices. Females of I. persulcatus lay 20,250 eggs per 1 hectare, and this number of eggs gives birth to 15,000 larvae. From this number, 7870 larvae hibernate and 6550 individuals became fed. The number of nymphs is 5930, among which 5110 individuals live up to spring, and 1390 became fed. The number of adult mites in autumn is 1250; in subsequent spring this number decreases to 780. The mean number of engorged females is 8. The mortality rate of ticks caused by the deficit of hosts increases from preimaginal stages to adults; for larvae, nymphs and imago this index is 16.6, 72.8, and 97.9%, respectively. Quotas of individuals with 3-, 4- and 5-year life cycle among the unfed imago are 70.4, 28.0, and 1.6%, respectively.

Animals↗
PubMed2005

Study of soybean leafhoppers fauna and an investigation on biology of dominant species Empoasca decipienspaoli in Karaj area.

The fauna of soybean leafhoppers and the biology of dominant species were investigated in Karaj during 1992-1994. For identification of species the male genitalia and other taxonomic characters were used. In order to find the duration and number of nymph stages, leaf cages were used on the plants. A thermograph was used to study the effect of temperature on nymphal stages in greenhouse. To study biology of E. decipiens in field four cages prepared and the trials has done inside them, and weekly all its life cycle observed. The following six species from four genera were identified: Empoasca decipiens Paoli, Macrosteles quadripunctulatus (KIrschbaum), M. laevis (Rib). Psammotettix alienus (Dahlbom), P. Striatus (Linne), Neoaliturus tenellus (Baker). Our investigations showed that Empoasca decipiens was the dominant species with the highest abundance. This specie is one of the important pests in many parts of Iran where oilseed crops are planted. The results showed that the soybean leafhopper over winters as adult under the debris of host plants and weeds. The first generation completes their life cycle on weeds before planting soybean. The second, third, and fourth generation lived on soybean. The time taken for the first, second, third, fourth and fifth nymphal stages were 6-7, 5-6, 2-4, 4-6 and 6-8 days, respectively. Adult longevity was 17-19 days, so that duration of first generation on weeds was 54-66 days. Our experiments showed that, at 18 degrees C condition, the first stages have been the maximum nymph period and at 23 degrees C condition, have been the lowest period.

Animals↗
PubMed2005

Seasonal coincidence between rosy apple aphid fundatrices and their parasitoids: implications for an early biological control of Dysaphis plantaginea.

The potential contribution of the aphid parasitoid Ephedrus persicae Froggatt (Hymenoptera: Braconidae, Aphidiinae) in regulating stem mothers of the rosy apple aphid Dysaphis plantaginea (Passerini) (Homoptera: Aphididae) was investigated in culture conditions using both species' phenological emergence data in spring and host stage suitability trials. In 2003, emergence of E. persicae started on April 1st, i.e., 108.2 degree-days (base: 4.5 degrees C; start date: January 1st) later than its host on March 10th. When less than 3% of parasitoids had emerged on April 12th, more than 97% of D. plantaginea stem mothers had moulted beyond their 1st instar. The latest parasitoids left their diapause mummies in late April as the majority of fundatrices had reached the adult stage. Parasitisation trials demonstrated the suitability for E. persicae of all developmental stages of rosy apple aphid fundatrices, including mature individuals. No offspring were deposited by fundatrices parasitised as Ist-instar nymphs but later instars did produce a progeny whose size was substantially reduced compared with unparasitised individuals, and scaled against their age at the time of parasitisation. Although the temperature accumulation required for emergence in spring is reached later for E. persicae than for its host aphids, thus allowing part of the stem mother population to temporarily escape parasitisation and reach maturity, the marked reduction in fecundity of individuals parasitised even as late-instar nymphs does confer to E. persicae a non-negligible role in potentially regulating D. plantaginea.

Animals↗
PubMed2004

[Participation of Ixodes ricinus developmental stages in transmission of Anaplasma (Ehrlichia) phagocytophila].

The present study constitutes a survey on the prevalence of human granulocytic ehrlichiosis agent, Anaplasma (Ehrlichia) phagocytophila, infecting ticks, Ixodes ricinus. I. ricinus were collected in the spring and autumn of the years 2000-2002 in western Pomerania (Poland), on vegetation using cloth drags. In all, 3340 individuals of I. ricinus were collected from the sampling sites. This total comprised of 511 females, 525 males, and 1998 nymphs. The prevalence of this pathogen in ticks was assessed using the PCR technique (a fragment of 16S rDNA gene amplified with EHR 521 and EHR 747 primers). The overall prevalence of A. phagocytophila in I. ricinus was 3 % in adults but only 1.6% in nymphs.

Anaplasma phagocytophilum↗
PubMed2000

[The occurrence of Ixodes ricinus in the selected recreative areas in the province of Szczecin. Part II].

The aim of the study was to estimate the occurrence (the quantative and rate percent) of Ixodes ricinus in the popular recreation areas in Szczecin (Arkonka, Osów, Głebokie, Landscape Park of Szczecin, Dabie Forest Park, Zdroje Forest Park) and in province of Szczecin (Forest of Goleniów, Ińsko, Pobierowo, Chojna). Investigations were performed in 1998 year, twice on each places; in May/June and repeted in September/October. The temperature and humidity of air were measured. Obtained specimens were regard of sex and growing stage during each collection. A total of 2.055 specimens collected 49% were nymphs, 13.9% female, 11.3% male and 25.8% larvaes. The nymphs the most frequently were in spring when humidity of air was 55% and temperature 24 degrees C. The larvaes, in autumn were most frequently (31.4%) then in spring (20.5%) when the temperature of the air was 18-22 degrees C, and the humidity from 60 to 85% during the collections.

Animals↗
PubMed2002

[The occurrence of Ixodes ricinus in the selected recreative areas in the province of Szczecin. Part III].

Within the last years, the incidences of diseases transmitted by Ixodes ricinus tick have rapidly increased. We estimated the occurrence of Ixodes ricinus in the popular recreation urban areas in Szczecin and in the Province of Szczecin. The study was carried out in 1999, with two samples at each site, and were compared with data of 1998. The temperature and humidity of air were measured. The most ticks were found in the range of 70-80% relative humidity of air. Among 3.198 specimens collected 59.5% were nymphs, 19.0% larvae, 11.1% females and 10.4% males. The nymphs were the most frequent in spring and in autumn, while the larvae were most frequent in autumn (26.2%) then in spring (11.9%).

Animals↗
PubMed2003

[Evaluation of occurrence of spirochetes Borrelia burgdorferi sensu lato in Ixodes ricinus ticks in selected areas of the Lublin region by polymerase chain reaction method (PCR)].

During the period 2001-2002, 1098 Ixodes ricinus ticks were collected at forest sampling sites and the degree of their infection with Borrelia burgdorferi spirochetes was determined by means of polimerase chain reaction (PCR). The presence of Borrelia burgdorferi genetic material was noted in 69 cases (6.3%). It was confirmed that the frequency of infection of adult forms of ticks (males and females) was nearly twice as high as nymphs. The highest degree of infection was observed in females--9.5%. The degree of infection among males and nymphs was smaller--5.9% and 4.4% respectively in individual provinces. The percentage of infected females ranged from 7.9% in the Zamość Province to 13.6% in the Włodawa Province. In males, the percentage of infected ticks remained within the range from 3.1% in the Lublin Province to 13.3% in the Lubartów Province.

Animals↗
PubMedDate not supplied

[The correlation variability of the morphometric traits in 4 species of ixodid tick species (Ixodidae)].

Correlation analysis of 10 characters was run in three species of Dermacentor, D. nuttalli, D. ushakovae, D. niveus, and in Ixodes persulcatus, separately for each phase and sex. Correlation coefficients are very low in larvae of all species. In male nymphs correlation coefficients are on the same level in all species while the correlation coefficient level in female nymphs reflects the degree of independence of the development of characters. This defines the degree of manifestation of sexual dimorphism at the nymphal phase: the more rigid the connections between the characters the less number of characters shows sexual differences. At the phase of imago the lowest correlation coefficients are in I. persulcatus. This species displays most distinct differences in the morphology of females and males. On the basis of comparison of correlation and variability coefficients the functional role of the characters is discussed.

Animals↗
PubMedDate not supplied

[The morphogenic diapause of the taiga tick and the methods for its quantitative assessment in a field experiment].

Methods of quantitative estimation of critical photoperiod and critical date of entering the diapause in ixodids have been worked out. S-shaped dependence of the number of diapausing larvae and nymphs of Ixodes persulcatus on their feeding periods has been shown. It has been established that in Central Udmurtia the average critical date of entering the diapause in 50% of satiated larvae and nymphs falls at the 18th and 29th of June, respectively, with the light day length of 17 hr 10 min and 16 hr 22 min.

Animals↗
PubMed1991

Differential detachment from resting hosts of replete larval and nymphal Ixodes ticks.

To determine whether replete subadult Ixodes ticks detach more frequently from resting than from active hosts, diverse rodents and lizards were caged in an apparatus designed to record the ticks' sites of detachment relative to the resting site of the host. Replete larval Ixodes ricinus and Ixodes dammini accumulated mainly beneath the resting places of the mice (Apodemus agrarius and Peromyscus leucopus) most frequently parasitized in nature. Although nymphal I. ricinus similarly detached where these mice rested, nymphal I. dammini detached more randomly. When lizards were used as hosts, both subadult stages of I. ricinus tended to detach away from their main resting sites; these ticks detached from squirrels more randomly. Detachment ratios for other rodent hosts, that are abundantly infested by the larvae of these ticks in nature (Apodemus flavicollis and Clethrionomys glareolus), could not be derived because nymphs generally failed to attach. Our observations are consistent with reports that both subadult stages of I. dammini, but not the adult, feed on the same kind of nest-dwelling hosts and that the host range of I. ricinus is less focused. Detachment of mouse-feeding larvae from resting mice promotes subsequent nymphal attachment to conspecific hosts, and the absence of such behavior among nymphs facilitates access of the resulting adults to deer.

Animals↗
PubMed1990

Tick parasitism and antibodies to Borrelia burgdorferi in cats.

Ticks were removed from naturally infested cats, and serum samples from these cats were tested for antibodies to Borrelia burgdorferi. Twenty-two of 93 cats (23.7%) had one or more motile stages of Ixodes dammini attached. Of 2 larvae and 20 nymphs removed from cats, 1 larva and 2 nymphs were infected with B burgdorferi. Spirochetes were not found in tissues of 13 female and 4 male ticks. Ten of 71 serum samples analyzed by indirect fluorescent antibody staining or ELISA contained antibodies to this spirochete. Maximal antibody titers were 1:256 and 1:2,560, respectively. At titers greater than or equal to 1:160 in ELISA, seropositivity ranged from 8.8% (n = 34 sera tested from 34 cats) in May through July to 33.3% (n = 12 cats tested) during February through April. In clinical studies of 30 cats, there were nearly equal percentages of seropositive cats with limb or joint disorders not accompanied by fever, anorexia, or fatigue (5 of 21 cats) and cats with these signs of illness but lacking lameness (2 of 9 cats.)

Animals↗
PubMed1978

Transmission of Kyasanur Forest disease virus by Rhipicephalus haemaphysaloides ticks.

Larvae of Rhipicephalus haemaphysaloides were infected with Kaysanur Forest disease (KFD) virus by feeding on viraemic rodents and reared into next generation larvae. Fed larvae, nymphs, unfed adults, fed adult males, and females after oviposition were found infected, while the larvae were found free from infection. Nymphs and adults transmitted the infection by bite to rodents and rabbits respectively. The virus was also passed through a second rodent-tick cycle. Adult ticks showed a titre of 3.1 to 4.5 dex mouse LD50/0.03 ml, and the virus was also detected 245 days after infection.

Animals↗
PubMed1989

Composition and distribution of retinal and 3-hydroxyretinal in the compound eye of the dragonfly.

Retinoids in the compound eyes of nymphs and adult dragonflies in 11 families of the 3 suborders were extracted by the oxime method, and analysed by high performance liquid chromatography. Almost all of the species examined contained both retinal and 3-hydroxyretinal in the compound eye. The ratio of 11-cis 3-hydroxyretinal to 11-cis retinal (3-OH ratio) was calculated as an index of the retinoid composition. The 3-OH ratios of the whole eye of nymphs in all the suborders and of adults of the suborder Zygoptera were very high, 2.2 at the minimum, but in Anisozygoptera and Anisoptera most of the ratios were distributed between 1 and 2.7. In the family Gomphidae, exceptionally low 3-OH ratios, less than 1, were observed in several species. The regional distributions of the retinals in the adult compound eyes were also examined. In the Zygopteran compound eye, both retinals were distributed evenly all over the eye, while in the compound eye of the other two suborders, the 3-OH ratios in the dorsal area of the eye were extremely low. In several species of Gomphidae and Libellulidae the ratios in the dorsal areas were zero. From the correspondence of these results and the compartment of the compound eye, it appeared that the large ommatidia in the dorsal area contained only retinal. This was confirmed when the large facet region in the dorsal part of the compound eye of an Anax was excised and examined, and only retinal was detected. However, the ventral area of the true dragonflies' compound eye which did not include the large ommatidia contained both retinals, and the 3-OH ratio was more than ten. The biological significance of using both retinals as chromophores of visual pigments in the dragonfly eye is discussed in relation to the structure of the ommatidia and to the vision of dragonflies.

Animals↗