Parasitism of mosquitoes (Diptera: Culicidae) by larval mites (Acari: Parasitengona) in Adelaide, South Australia

Larval mites (Acari) from the cohort Parasitengona were collected from adult female mosquitoes captured in Adelaide, South Australia, from 1997 to 2000. Larvae from three families were identified: Arrenuridae, Hydryphantidae and Erythraeidae. Arrenurid larvae were associated with mosquitoes that use ground pools for larval habitat, while hydryphantids were associated with tree-hole and container-breeding species. Only a single erythraeid record was made. The overall prevalence of parasitism was very low (0.27% of 19 280 mosquitoes) and ranged from 0 to 5.6% for the 16 mosquito species collected. New mite–host records are presented.     

Prevalence of gastrointestinal parasites in captive non‐human primates of twenty‐four zoological gardens in China

Captive primates are susceptible to gastrointestinal (GIT) parasitic infections, which are often zoonotic and can contribute to morbidity and mortality. Fecal samples were examined by the means of direct smear, fecal flotation, fecal sedimentation, and fecal cultures. Of 26.51% (317/1196) of the captive primates were diagnosed gastrointestinal parasitic infections. Trichuris spp. were the most predominant in the primates, while Entamoeba spp. were the most prevalent in Old World monkeys (P < 0.05). These preliminary data will improve the management of captive primates and the safety of animal keepers and visitors.     

Noninvasive Monitoring of the Health of <Emphasis Type="Italic">Pan troglodytes schweinfurthii</Emphasis> in the Kibale National Park,Uganda

We assessed the health status of chimpanzees (Pan troglodytes schweinfurthii) of the Kanyawara group in the Kibale National Park in Western Uganda via noninvasive methods. We conducted visual veterinary inspection, parasitological and urine analysis in association with behavioral observations, causing minimal disturbance or stress to individually recognized chimpanzees. We applied multiple parasitological techniques to 252 stool samples to compare their efficacy in detecting parasitic infection and to increase the power of detecting a wide range of parasites at a more sensitive level. We examined 76 urine samples via a quick detection method to evaluate multiple parameters of urine that indicate organ dysfunction. Results of the different analyses are mutually supportive and provided useful information for monitoring bodily condition and diseases. The multifaceted health evaluation system is a beneficial tool for monitoring long-term and short-term changes in health status due to environmental stress, seasonal dietary change, and disease in wild chimpanzee populations. Use of this method to detect changes in health, when employed together with behavioral observations, may also provide important insights into the potential effects of self-medicative behaviors.     

Malarial parasites decrease reproductive success: an experimental study in a passerine bird

Malarial parasites are supposed to have strong negative fitness consequences for their hosts, but relatively little evidence supports this claim due to the difficulty of experimentally testing this. We experimentally reduced levels of infection with the blood parasite Haemoproteus prognei in its host the house martin Delichon urbica, by randomly treating adults with primaquine or a control treatment. Treated birds had significantly fewer parasites than controls. The primaquine treatment increased clutch size by 18%; hatching was 39% higher and fledging 42% higher. There were no effects of treatment on quality of offspring, measured in terms of tarsus length, body mass, haematocrit or T-cell-mediated immune response. These findings demonstrate that malarial parasites can have dramatic effects on clutch size and other demographic variables, potentially influencing the evolution of clutch size, but also the population dynamics of heavily infected populations of birds.     

<Emphasis Type="Italic">Cyclospora cayetanensis</Emphasis> and other intestinal parasites associated with diarrhea in a rural area of Jordan

Cryptosporidium spp. and Cyclospora cayetanensis have emerged as important causes of epidemic and endemic diarrhea in immunocompetent and immunocompromised hosts. The exact modes of transmission in certain rural areas are still unclear. Reports of water-borne and food-borne outbreaks suggest that fecally contaminated water or food acts as a vehicle of transmission. Two hundred stool samples of patients with gastroenteritis from four health centers in a rural area of Jordan were examined using formalin-ethyl acetate concentration, wet preparation, and modified acid-fast staining methods. Oocysts of C. cayetanensis and Cryptosporidium spp. were found in 6% and 8% of the samples respectively, mainly those of children. Parasites such as Entamoeba histolytica, Giardia lamblia, and other enteropathogens were also observed. The results reflect the seasonality of natural cyclosporiasis and cryptosporidiosis, being higher in the spring. The risk factors that were found by the Fisher test to be significant and might be associated with illness are the source of drinking water, contact with animals, and eating unwashed vegetables (p<0.028, p<0.0005, p<0.00005 respectively).     

A PCR-based survey on Phytomonas (Euglenozoa: Trypanosomatidae) in phytophagous hemipterans of the Amazon region

ABSTRACT. We have surveyed 244 hemipterans from Western Brazilian Amazônia for the presence of trypanosomatids and identification of members of the genus Phytomonas. Examination by phase microscopy of squashes of insect salivary glands (SG) and digestive tubes (DT) revealed that 44% (108/244) of insects from seven families harbored trypanosomatids. Infections were 5 times more frequent in Coreidae than in all other families together. Smears of SG and DT of the dissected insects were fixed on glass slides with methanol and stained with Giemsa for morphological analysis. DNA was recovered from these preparations and submitted to a PCR assay that permitted amplification of all trypanosomatid genera using primers of conserved sequences flanking a segment of the spliced leader (SL) gene. Upon PCR amplification of the recovered DNA, amplicons were hybridized with an oligonucletide probe (SL3′) complementary to a SL intron sequence specific for flagellates of the genus Phytomonas. Among the trypanosomatid‐positive insects, 38.8% harbored Phytomonas spp., corresponding to an overall Phytomonas prevalence of 17.1% among phytophagous bugs, their putative vectors. Since many Phytomonas are pathogenic in plants, this high prevalence in their vectors emphasizes the permanent risk of exposure to disease by native and cultured plants of the Amazon region.     

Evolution of hemocyte concentration in the melanogaster subgroup species

We explore two possible hypotheses about the ecological factors driving the evolution of hemocyte load in insects. The first is parasite infection risk, its variability and the genetic diversity of parasites. The other supposes that all the other factors of environmental stress drive the evolution through a pleiotropic selection on metabolic rate. The two hypotheses are tested with data on hemocyte load and ecology of six Drosophila species of the melanogaster subgroup. Hemocyte load correlates significantly with the parasite-driven selection index, but not with the stress selection index. The result being based on too little data to conclude definitely, this work must be considered more as a methodological research based on published results on insect physiology immunity and ecology rather than an empirical evidence of such a relationship.     

Juvenile infection and male display: testing the bright male hypothesis across individual life histories

Current tests of the bright male hypothesis focus on assaysof adult disease resistance and their relation to male traitdevelopment and female choice. We suggest that if parasiteshave significant harmful effects on juvenile stages of a host,then females selecting males that effectively signal juvenileparasite resistance may gain a significant "good genes" benefit.Currently, there is no information on juvenile and adult infectionor resistance in the same male and whether adult male displayssignal juvenile parasite resistance. In the present study, wemeasure infection of the ectoparasitic louse, Myrsidea ptilonorhynchi,in individual male satin bowerbirds (Ptilonorhynchus violaceus)both as juveniles and nine or more years later as adults. Wetest hypotheses that examine the role of juvenile parasite infectionin mediating sexual selection. We found that (1) juvenile infectionis higher than adult infection in the same individuals, (2)adult males able to hold display sites have lower juvenile infection,and (3) juvenile and adult infection in the same individualsare not significantly correlated. In addition, comparisons amonga larger set of individuals from a single year show that bloodand ectoparasite infections are highly correlated, and bothdecrease with male age and are inversely related to male courtshipsuccess. These results, combined with the evidence that femalesmate exclusively with bower-holding males support the hypothesisthat females use adult male display traits to identify maleswith a high level of juvenile disease resistance. We suggestthat effective tests of the bright male hypothesis should include(1) assessment of infection resistance in both subadult andadult life history stages, (2) tests of whether differencesin age-specific resistance are indicated in adult male displays,and (3) tests to determine if females attend to these traitsin mate choice. Although these requirements increase the difficultyof testing the bright male hypothesis, they are necessary fora more accurate assessment of the effects of parasites on maledisplay and female choice.     

Ethologic and ontogenic significance of the Pliocene trace fossil Sinusichnus sinuosus from the northwestern Mediterranean

The trace fossil Sinusichnus sinuosus Gibert 1996 is described and interpreted as an open burrow system, attributed to a crustacean tracemaker, that shares some features with fodinichnial networks, such as Thalassinoides and Ophiomorpha , and with graphoglyptid burrows, such as Protopaleodictyon and Cosmorhaphe. These similarities suggest that Sinusichnus could have been produced by an animal combining deposit-feeding and farming (or trapping) strategies. The Sinusichnus record has yielded juvenile and adult burrows, often in close association. On account of minor morphologic differences between the two, juvenile tracemakers could have employed an agrichnial feeding strategy, whereas adults could have employed fodinichnial feeding.