Parasite Index Research Articles

Comparative effects of different organic materials on nematode community in continuous soybean monoculture soil

Plant parasitic nematodes are the most devastating pest in continuous soybean monoculture, which have been managed mainly by chemical nematicides. However, safe and alternative methods need to be developed. A variety of organic materials are used for this purpose, but the control efficiency of different organic materials for nematodes has not been assessed in a comparative manner. Therefore, based on a 7-year experiment of continuous soybean monoculture, we directly compared the effects of different organic materials (maize straw combined with chemical fertilizer (F + S), poplar leaf combined with chemical fertilizer (F + L), cow manure combined with chemical fertilizer (F + C) and only fertilizer as CK) on nematode trophic groups and functional guilds under the same condition. Despite the lack of total nematode density differences, organic materials altered the soil nematode community in a soybean monoculture system. The relative abundance of plant parasites was highest in F + L treatment, followed by F + S treatment, while lowest in F + C and CK treatments. Meanwhile, bacterivores and fungivores had a higher relative abundance in CK and F + C treatments and a lower relative abundance in F + L and F + S treatments. Furthermore, significant treatment effects were also observed on the relative abundance of different functional guilds, except colonizer-persister (c-p) 5 plant parasites. The relative abundance of c-p 2 bacterivores was significantly higher in CK and F + C treatments than in F + S and F + L treatments, while the relative abundance of c-p 3 omnivore-carnivores was significantly higher in F + S and F + L treatments than in CK and F + C treatments. Organic materials treatments had a significant effect on Shannon index (H’), plant parasite index (PPI), structure index (SI) and enrichment index (EI) (P < .05), and the significant effects varied among different organic materials treatments. The results of this study suggest that the influence on the soil nematode community of organic materials is associated with their chemical composition, and so is its efficacy of controlling plant parasitic nematodes.

Metazoan parasite communities of Leporinus macrocephalus (Characiformes: Anostomidae) in cultivation systems in the western Amazon, Brazil

ABSTRACT In the Amazon, the growing demand for fish has been boosting the expansion of fish farms. However, the intensification of cultivation can generate disequilibrium in the parasite-host environment, predisposing fish to parasitic infections. The objective of this study was to evaluate the community structure of metazoan parasites in cultivation systems of piauçu, Leporinus macrocephalus, in the state of Acre, Brazil. We examined 100 specimens from a semi-intensive cultivation system (earth tanks) and 100 from an extensive system (dams). Overall 66.5% of the hosts were parasitized. We collected 1,240 parasite specimens, classified in 15 metazoan taxa (10 monogenoidean, one digenean and four nematodes). The parasite prevalence was higher by Monogenoidea in the dams, and by Nematoda in the earth tanks. The parasitic indexes were, in general, low and varied among species. Monogeneoidea had higher values for quantitative and ecological descriptors of parasitism in the dams, while Nematoda had higher values in the earth tanks. A single species of Digenea was found in the dams, with low prevalence. No taxon was classified as central. In the dams, parasite abundance was correlated only with total fish length, while in the earth tanks, it was positively correlated with total length, weight and condition factor of fish. The endoparasite and ectoparasite infracommunities presented higher richness, dominance, diversity and evenness, respectively, in the earth tanks and in the dams. This is the first study of ecological descriptors of parasites of L. macrocephalus in the Amazon.

Malaria prevalence in Mangaluru city area in the southwestern coastal region of India

BackgroundMalaria is highly prevalent in many parts of India and the Indian subcontinent. Mangaluru, a city in the southwest coastal region of Karnataka state in India, and surrounding areas are malaria endemic with 10–12 annual parasite index. Despite high endemicity, to-date, very little has been reported on the epidemiology and burden of malaria in this area.MethodsA cross-sectional surveillance of malaria cases was performed among 900 febrile symptomatic native people (long-time residents) and immigrant labourers (temporary residents) living in Mangaluru city area. During each of dry, rainy, and end of rainy season, blood samples from a group of 300 randomly selected symptomatic people were screened for malaria infection. Data on socio-demographic, literacy, knowledge of malaria, and treatment-seeking behaviour were collected to understand the socio-demographic contributions to malaria menace in this region.ResultsMalaria is prevalent in Mangaluru region throughout the year and Plasmodium vivax is predominant species compared to Plasmodium falciparum. The infection frequency was found to be high during rainy season. Infections were markedly higher in males than females, and in adults aged 16–45 years than both younger and older age groups. Also, malaria incidence was high among immigrants compared to native population. In both groups, infection rate was directly correlated with their literacy level, knowledge on malaria, dwelling environment, and protective measures used. There was also a significant difference in treatment-seeking behaviour between these two groups.ConclusionsMalaria incidences in Mangaluru region are predominantly localized to certain hotspot areas within the city, where socioeconomically underprivileged and immigrant labourers are densely populated. These areas have inadequate sanitation and constant water stagnation, harbouring high vector density and contributing to high infection incidences. Additionally, people in these areas seldom practice preventive measures such as using bed nets. The high incidences of malaria in adults are due to minimal cloth wearing, and long working hours stretching to late evenings in places with high vector density. Instituting heightened preventive public measures by governments and creating awareness on using preventive protective and environmental hygienic measures through educational programmes may substantially reduce the risk of contracting infections in these areas and spreading to other areas.

Urban malaria transmission in a non-endemic area in the Andean region of Colombia.

BACKGROUNDRapid urbanisation in difficult socio-economic conditions such as inadequate housing infrastructure, lack of public services, improper sanitation, and poor water drainage systems in vegetation-rich areas lead to ecological conditions that are conducive to the breeding of mosquitoes and transmission of malaria, in semi-urban and urban settings.OBJECTIVESThis study aimed to describe the cases of malaria that were reported in the peri-urban areas of Pereira (Colombia), between 2008 and 2015.METHODSA retrospective study was conducted using data from the Malaria Surveillance System 2009-2015 and an outbreak study (between December 2008 and March 2009). Frequency distributions and summary measures, as well as univariate analysis were performed for all the variables in consideration. The annual parasite index (API) was calculated.FINDINGSData on 214 cases were obtained from the surveillance system. A majority of the cases were reported in men (63.1%), followed by in children < 15 years (23.8%), and were caused predominantly by Plasmodium vivax (86.0%), with most of the infection occurring in the urban areas (52.8%) of Pereira. The API, by sex and age group, was higher among men ≥ 80 years. The outbreak study reported 14 cases of malaria in rural/peri-urban neighborhoods, and it was observed that the anopheline breeding sites were in close proximity to the houses in these areas. This population did not use protective measures against mosquitoes and chemical control was conducted through residual and spatial insecticide spraying.MAIN CONCLUSIONSThis study suggested the presence of autochthonous malaria transmission, in Pereira, between 2008 and 2015, most of which were cases of P. vivax. A greater intensity was observed between 2008 and 2009 when malaria was possibly reintroduced to the region. During the years of the study, a gradual decrease in the number of reported cases of malaria was observed in Pereira, except for the time period between 2008 and 2009 when a spike was noted (estimated using the API); this was most likely caused by an outbreak. Interventions that are more aggressive in nature are required to prevent further malarial transmission and dissemination.

The study of response of electro-optic phase modulator based on LiNbO3 with the aim of improving the accuracy of fiberoptic gyroscope

The work offers the method for a study of parasitic refractive index drift (RID) of electro-optical modulator (EOM) based on the lithium niobate (NL) crystal under the action of applied electric voltage. As a result there is proposed a method of compensation EOM’s inertial behavior. Described method can be used for improving the accuracy of fiber-optic interferometric sensors and of fiber-optic gyroscope in particular.

Diversity of soil nematode communities in the subalpine and alpine forests of western Sichuan, China.

In order to understand the diversity of soil nematodes in the subalpine/alpine forests of the eastern Qinghai-Tibet Plateau, soil nematodes in the primary forest, mixed forest and secondary forest of Abies faxoniana were extracted by elutriation and sugar-centrifugation method in July 2015, and the composition and structure characteristics of soil nematode communities were studied in the three forests at different altitudes. A total of 37950 soil nematodes were collected, which belonged to 20 families and 27 genera, and the mean density was 4217 ind·100 g-1 dry soil. Filenchus was the dominant genus in the primary forest, and Filenchus and Pararotylenchus in the mixed forest and secondary forest, respectively. The individual number of each dominant genus was significantly affected by forest type. All nematode individuals were classified into the four trophic groups of bacterivores, fungivores, plant-parasites and omnivore-predators. The fungivores were dominant in the primary and secondary forest and the bacterivores in the mixed forest. The number of soil nematode c-p (colonizer-persister) groups of c-p 1, c-p 2, c-p 3 and c-p 4 accounted for 6.1%, 51.1%, 30.0% and 12.7% of the total nematode abundance, respectively. The maturity index (MI), the total maturity index (∑MI) and the plant parasitic index (PPI) of soil nematodes decreased gradually with the increase of altitude. The nematode channel ratio in the mixed forest was higher than 0.5, but that in the primary forest and secondary forest was below 0.5. The forest type significantly affected the soil nematode maturity index and channel ratio, but the forest type, soil layer and their interaction had no significant effect on the diversity index. There were obvious diffe-rences in the composition, nutrient structure and energy flow channel of soil nematodes in the subalpine/alpine forests of western Sichuan, providing an important reference for understanding the function of soil nematodes in soil processes of this region.

Effect of pea crab Pinnotheres vicajii (Chhapgar, 1957) on immunocompetence of bivalve Paphia malabarica (Chemnitz, 1782)

The endosymbiont-host relationship between a pea crab and its bivalve host has been studied previously using bivalve's multi-physiological parameters. The present study is first of its kind that uses hemocyte's immune functionality to evaluate the symbiotic relationship between bivalve Paphia malabarica and its symbiont crab, Pinnotheres vicajii. The sampling was carried out at two stations (differed in nutrient concentration, productivity, and bacterial abundance) located along the southwest coast of India. The results showed lower immunocompetence in the case of bivalves infested with pea crabs. The lowering of hemocyte population was the most prominent and perhaps the initial reaction in response to focal inflammation or wound inflicted by the pea crabs. A significant lowering of phagocytosis, lysozyme, and esterase activity was also observed, indicating the detrimental impact of crab infestation. Interestingly, no significant correlation was found between parasitism and condition index despite the lower immunocompetence, validating the effectiveness of using hematological parameters in comparison to other life-history traits. This indicates that the immune parameters being directly related to the organism's metabolic state can elucidate the early effect of stressors, therefore, proving to be a better proxy for understanding a host-pathogen relationship. Disparity found in bivalve's immunocompetence between the sampling sites could be linked to either variation in environmental parameters, the size of the symbiont or the infection level. Our preliminary results provide a direction towards examining immunodepression in parasitized bivalves by considering ex-situ controlled parasitism induction along with varying environmental conditions. In view of this, efforts must be directed towards minimizing pea crab's outbreaks, especially in cultivated shellfish farms. Future studies should elucidate molecular mechanisms involved in the immunocompetence of P. malabarica, hosting the parasitic pea crabs.

Parasite community dynamics in an invasive vole – From focal introduction to wave front

Multiple parasite species simultaneously infecting a host can interact with one another, which has the potential to influence host-parasite interactions. Invasive species typically lose members of their parasite community during the invasion process. Not only do the founding population escape their parasites, but the rapid range expansion of invaders once in the invaded range can lead to additional stochastic loss of parasites. As such, parasite community dynamics may change along an invasion gradient, with consequences for host invasion success. Here, we use the bank vole, Myodes glareolus, introduced as a small founding population at a point source in the Republic of Ireland in c.1920's and its ecto- and endoparasites to ask: i) how does the parasite community vary across an invasion gradient, and ii) are parasite community associations driven by host traits and/or distance from the point of host introduction? We sampled the parasite community of M. glareolus at the proposed focal site of introduction, at mid-wave and the invasion front, and used a parasite interactivity index and statistical models to determine the potential for the parasite community to interact. Bank voles harboured up to six different parasite taxa, with a significantly higher parasite interactivity index at the foci of introduction (z = 2.33, p = 0.02) than elsewhere, suggesting the most established parasite community has greater opportunities to interact. All but one of four synergistic parasite community associations were driven by host traits; sex and body mass. The remaining parasite-parasite associations occurred at the mid-point of the invasion wave, suggesting that specific parasite-parasite interactions are not mediated by distance from a focal point of host introduction. We propose that host traits rather than location along an invasion gradient are more likely to determine parasite-parasite interactions in the invasive bank vole.

The effect of excluding ungulates on the abundance of ixodid ticks on wild rabbit (Oryctolagus cuniculus).

Tick abundance depends heavily on host density, so reducing access to the host should reduce tick populations in a determined area. In this study we compared the Parasitic Index (PI=average number of ticks per rabbit) of two wild rabbit populations separated 16years ago by a fence keeping ungulates from moving freely. Two areas were selected (closed and open) wherein 50 wild rabbits per area were sampled for ticks. The PI in the open area (PI=989.62) was significantly higher than in the closed area (PI=515.40). Hyalomma lusitanicum Koch was globally the most abundant species, followed by Rhipicephalus pusillus Gil Collado, Rhipicephalus bursa Canestrini and Fanzago, Haemaphysalis hispanica Gil Collado, Rhipicephalus sanguineus s.l. Latreille and Ixodes ventalloi Gil Collado. Differences between areas varied depending on the species. The number of H. hispanica, R. bursa and R. pusillus were significantly more abundant on rabbits in the closed area, whereas H. lusitanicum predominated in the open area. Ungulates in the open area may have played an important role as the main or alternative host for ticks and/or drawing some tick species away from rabbits. In the closed area other reasons such as inter-specific competition could have influenced the tick abundance. These results show a clear reduction in tick abundance for at least 16years as well as influenced species distribution.

Diagnostic Efficacy of Microscopy, Rapid Diagnostic Test and Polymerase Chain Reaction for Malaria Using Bayesian Latent Class Analysis

Introduction: The diagnostic techniques for malaria are undergoing a change depending on the availability of newer diagnostics and annual parasite index of infection in a particular area. At the country level, guidelines are available for selection of diagnostic tests; however, at the local level, this decision is made based on malaria situation in the area. The tests are evaluated against the gold standard, and if that standard has limitations, it becomes difficult to compare other available tests. Bayesian latent class analysis computes its internal standard rather than using the conventional gold standard and helps comparison of various tests including the conventional gold standard. Materials and Methods: In a cross-sectional study conducted in a tertiary care hospital setting, we have evaluated smear microscopy, rapid diagnostic test (RDT), and polymerase chain reaction (PCR) for diagnosis of malaria using Bayesian latent class analysis. Results: We found the magnitude of malaria to be 17.7% (95% confidence interval: 12.5%–23.9%) among the study subjects. In the present study, the sensitivity of microscopy was 63%, but it had very high specificity (99.4%). Sensitivity and specificity of RDT and PCR were high with RDT having a marginally higher sensitivity (94% vs. 90%) and specificity (99% vs. 95%). On comparison of likelihood ratios (LRs), RDT had the highest LR for positive test result (175) and the lowest LR for negative test result (0.058) among the three tests. Conclusion: In settings like ours conventional smear microscopy may be replaced with RDT and as we move toward elimination and facilities become available PCR may be roped into detect cases with lower parasitaemia.

Parasite infection and immune and health-state in wild fish exposed to marine pollution

Association between parasitism and immunity and health-state was investigated in wild Sebastes oculatus after having determined that pollution exposure is associated with altered immune and health-state parameters. Given the importance of the immune system in antiparasite defense we predicted: (i) parasite infection would be higher in pollution-exposed than in control fish and (ii) fish with lower immune and health-state parameters would show higher parasitism than fish in better condition. Metazoan parasite fauna was compared between pollution-exposed and non-exposed fish and parasitic indices were correlated with integrated measures of immunity and health-state. Results provided little support for the predictions; some parasite taxa increased, some decreased, and some were not affected in pollution-exposed fish despite their altered health and immunity. Furthermore, there was no link between individual immune and health-state parameters and parasitism. These findings highlight the complexity of host-parasite-environment interactions in relation to pollution in natural marine ecosystems.

Toxicity and parasiticidal in vivo and in vitro evaluation of acetic acid on metazoan ectoparasites in juvenile Mugil liza

In this study, the anti-parasitic activity of acetic acid was evaluated in vivo and in vitro in juveniles of Mugil liza. The parasites studied were the copepods Ergasilus lizae and E. versicolor and the monogenoideans Solostamenides cf. platyorchis and Ligophorus spp. To determine concentrations for use in the in vivo evaluation, and to determine the therapeutic index, a toxicity test (LC50-1h) was carried out using juveniles of M. liza. The LC50-1h was estimated at 1402.62mgL−1. Glacial acetic acid concentrations were determined for in vivo evaluation from the values of 0%, 25%, 50% and 75% of LC50-1h, which corresponded to concentrations of 0mgL−1 (control), 350.65mgL−1, 701.31mgL−1 and 1051.96mgL−1, respectively. Due to high mortality, fish exposed to 701.31mgL−1 and 1051.96mgL−1 concentrations were not examined in the in vivo evaluation. The results of the in vivo evaluation were presented in parasitic indexes of prevalence (P%), mean infestation intensity (MII) and mean abundance (MA). The MA values were used to determine the efficacy of the 350.65mgL−1 concentration for each parasite found, which was 100% for S. cf. platyorchis, 91.47% for Ligophorus spp. and 73.57% for E. lizae. No specimens of E. versicolor were found in the in vivo evaluation. The in vitro evaluation comprised toxicity tests (EC50-1h) for each parasite taxa. The EC50-1h values were 83.38mgL−1 for E. lizae, 89.97mgL−1 for E. versicolor, 144.79mgL−1 for S. cf. platyorchis and 289.58mgL−1 for Ligophorus spp. With the values of LC50-1h of M. liza and EC50-1h values of each parasite taxa, the therapeutic indices were calculated, ranging from 16.82 for E. lizae, 15.59 for E. versicolor, 9.69 for S. cf. platyorchis and 5.53 for Ligophorus spp. It is possible that the presence of parasites affected the survival of the fish during in vivo evaluation. Although E. lizae presented the highest therapeutic index, it was the taxon that presented the lowest efficacy, probably due to the strong adhesion in the gills by its modified antennas, even after the death of the parasite. It has been found that glacial acetic acid at a concentration of 350.65mgL−1 is an effective drug against M. liza parasites.

Outcome analysis of patients presenting with neurological manifestations of Plasmodium Vivax malaria in tertiary care hospital of Mumbai.

Objective: Plasmodium vivax (P. vivax) infection has been considered for a long time a benign and self-limited disease. Percentage of complicated cases of vivax malaria is on the increasing trend, cerebral malaria being the most dreaded and a potentially life-threatening complication. Material and Methods: A prospective observational study was done after institutional ethics committee approval from July 2011 to February 2012 at tertiary care hospital in Mumbai. We studied the clinical profile and outcome of all the 48 patients above the age of 12 years diagnosed with Cerebral Malaria. Results: Incidence of neurological manifestations of vivax malaria in our hospital was 14.15%, with 32(66.7%) out of 48 patients being males. The mean age of patients with neurological manifestations of vivax malaria was 29.66 years in discharged patients and 50.88 years in expired patients. Altered sensorium 37(77.1%) followed by convulsion 28(58.3%) were common findings, but focal neurological deficit, Bell’s palsy, ataxia, psychosis were also seen. Mortality was higher (62.5%) in patients with premorbid conditions (p value <0.05) and that of with other system involvements (87.5%) including hepatic, renal, hepatorenal, pulmonary involvement (p value<0.05). Association between outcome with older age & high parasite index patients is significant (p value<0.001), however no such significant association was found in terms of gender distribution. Conclusion: Plasmodium vivax, as has been traditionally believed, is no longer a benign species and is causing presentations akin to P. falciparum. It is imperative that clinicians are aware of and ready to handle the complications caused by Plasmodium vivax.

A study of clinical profile of malaria with special reference to complications and outcome

Background: Malaria has a wide clinical spectrum ranging from uncomplicated disease to a fatal one. The objectives were to study clinical profile of Malaria with special reference to its complications and outcome.Methods: A prospective observational study was done in a tertiary care hospital including total of 300 patients diagnosed with Vivax or Falciparum Malaria. Data on patients’ clinical details with investigations, complications, and outcome was recorded and analysed using SPSS version 17.Results: Out of 300 patients, 179 had Vivax and 121 had Falciparum Malaria. Oliguria, high coloured urine, altered sensorium, convulsion, breathlessness, bleeding was more common in Falciparum malaria. Hypoglycaemia, thrombocytopenia, renal and hepatic involvement and ALI/ARDS were also more common in falciparum group. However, ALI/ARDS was more fatal in vivax group. Complications, outcome and biochemical parameters were correlated with parasite index and the correlations were statistically significant. Out of 22 deaths, 12 patients were from falciparum and 10 were from vivax group. Most common complication leading to death was ARDS/ALI, followed by AKI, convulsion, hepatic involvement and bleeding in decreasing order in both types of Malaria. Three patients with parasitic index &lt;5% and 19 patients with parasitic index &gt;5% died.Conclusions: Clinical profile of Falciparum Malaria was more complicated. Metabolic complications with multi organ involvement, ALI/ARDS and mortality were more in Falciparum Malaria. Correlation of parasitic index with complications, biochemical parameters and outcome in both the groups was statistically significant.

An experimental approach to the immuno-modulatory basis of host-parasite local adaptation in tapeworm-infected sticklebacks

The evolutionary arms race of hosts and parasites often results in adaptations, which may differ between populations. Investigation of such local adaptation becomes increasingly important to understand dynamics of host-parasite interactions and co-evolution. To this end we performed an infection experiment involving pairs of three-spined sticklebacks and their tapeworm parasite Schistocephalus solidus from three geographically separated origins (Germany, Spain and Iceland) in a fully-crossed design for sympatric and allopatric host/parasite combinations. We hypothesized that local adaptation of the hosts results in differences in parasite resistance with variation in parasite infection rates and leukocyte activation, whereas parasites from different origins might differ in virulence reflected in host exploitation rates (parasite indices) and S. solidus excretory-secretory products (SsESP) involved in immune manipulation.In our experimental infections, sticklebacks from Iceland were more resistant to S. solidus infection compared to Spanish and German sticklebacks. Higher resistance of Icelandic sticklebacks seemed to depend on adaptive immunity, whereas sticklebacks of German origin, which were more heavily afflicted by S. solidus, showed elevated activity of innate immune traits. German S. solidus were less successful in infecting and exploiting allopatric hosts compared to their Icelandic and Spanish conspecifics. Nevertheless, exclusively SsESP from German S. solidus triggered significant in vitro responses of leukocytes from naïve sticklebacks. Interestingly, parasite indices were almost identical across the sympatric combinations.Differences in host resistance and parasite virulence between the origins were most evident in allopatric combinations and were consistent within origin; i.e. Icelandic sticklebacks were more resistant and their S. solidus were more virulent in all allopatric combinations, whereas German sticklebacks were less resistant and their parasites less virulent. Despite such differences between origins, the degree of host exploitation was almost identical in the sympatric host-parasite combinations, suggesting that the local evolutionary arms race of hosts and parasites resulted in an optimal virulence, maximising parasite fitness while avoiding host overexploitation.

Effects of optimized fertilization on nematode community in greenhouse soils

Excessive fertilization easily leads to the degradation of greenhouse vegetable fields, therefore rational fertilizations are important to maintain the production and sustainable development of vegetable. In this study, two fertilization treatments (optimized fertilization and conventional fertilization, noted as OF and CF, respectively) under continuous tomato-pepper cropping were arranged to investigate soil physicochemical properties, abundance and trophic groups of nematode and vegetable yield. The results showed that OF could maintain soil pH at the relatively higher level and increase the yield of tomato and pepper by 9.0% and 6.9% compared to CF treatment. In contrast to CF, OF increased nematode quantity and the relative abundance of bacterivores, but decreased the relative abundance of fungivores and plant-parasites, more obviously in the growth season of tomato. No obvious differences in plant parasite index, diversity, and richness were observed between CF and OF treatments across all sampling stages of tomato and pepper. Nematode channel ratio ranged from 0.39 to 0.64 in CF treatment, which was significantly lower than that in OF treatment (0.67-0.84), suggesting that the decomposition of food network was dominated by fungi in CF treatment but by bacteria in OF treatment. Based on soil physicochemical properties, nematode groups and vegetable yield, we concluded that optimized fertilization could not only increase vegetable growth but also improve soil ecological environment.

Chapiniella variabilis (Nematoda) parasitizing Chelonoidis carbonarius and C. denticulatus (Testudinidae) in the state of Piauí.

Chapiniella variabilis (Chapin, 1924), a strongylid nematode, was collected parasitizing the large intestine of the tortoises Chelonoidis carbonarius (Spix, 1824) (Cc) and C. denticulatus (Linnaeus, 1766) (Cd) in the Zoobotanical Park of the municipality of Teresina, state of Piauí, Brazil. The taxonomic identification was based on morphological and morphometric features, using bright-field and scanning electron microscopy. The present study adds new observations on the morphology, mainly relating to the mouth papillae, external and internal leaf-crown elements, excretory pore, deirids and male and female posterior end. The parasitic indices of prevalence (P), mean intensity (MI), mean abundance (MA) and range of infection (RI) of C. variabilis in these two tortoise species were: P = 100%, MI = 833.3, MA = 833.3, RI = 500-1,500 (Cc); P = 100%, MI = 472.2, MA = 472.2, RI = 333-500 (Cd). This record expands occurrences of C. variabilis to a new host, C. carbonarius, and to another state in Brazil, in the Neotropical region of South America. Adjustment to host management with the aim of improving hygiene and health conditions is suggested.

Virulence in the three-spined stickleback specific parasite Schistocephalus solidus is inherited additively

Parasite virulence is a key trait in host-parasite interactions and plays a crucial role in infection dynamics. Our study system offers the rare opportunity to study the virulence of an individual macroparasite (Schistocephalus solidus) in its vertebrate fish host (Gasterosteus aculeatus). The size of the tapeworm in the fish can be regarded as a good proxy for individual parasite virulence, as parasite size correlates negatively with fitness traits of the stickleback host (i.e. the bigger the parasite, the lower the host's reproductive success) as well as directly with the number of parasite offspring to be expected.To investigate how virulence is inherited, laboratory bred, parasite-naïve stickleback were infected with a cross of two S. solidus populations of either high or low virulence, as well as one hybrid cross between the two. The relative weight of the parasite as expressed in the parasite index served as a measure of virulence. Furthermore, we measured several condition and immune related traits in the fish host to assess parasite impact on the stickleback. We hypothesized that parasite virulence is to a large extent genetically determined and correlated with several fitness traits in the stickleback host.We found that virulence is inherited additively in S. solidus, with hybrids of high and low virulence parasites displaying intermediate levels. However, contrary to expectation, infection rate of S. solidus in three-spined stickleback is not related to virulence. Even though the presence of the parasite caused differences in host condition, these were indistinguishable between the different levels of virulence in this experiment. Fish immune traits also showed a response to infection but had no correlation with level of parasite virulence.With this experiment we have taken the first step towards understanding how virulence is inherited and how it is driven in the Schistocephalus-stickleback system, even though virulence, as measured here, does not directly translate into cost for the host. A better understanding of the costs inflicted on the host by S. solidus infection is needed to understand this interaction in greater detail.

Intestinal Parasitic Infection and Body Mass Index among School Children in Oshodi Lagos Nigeria

Background Intestinal parasitic infections are still major public health problems in the world particularly in developing countries These parasitic infections have adverse effect on the health status of individuals particularly children Objective The study is designed to determine the effect of nutritional status on the prevalence of intestinal parasites among the school children in Oshodi Lagos State Nigeria between June and August Methods A total of consented from seven public primary schools in Oshodi boys and girls school children provided stool samples their height and weight measured to calculate the body mass index BMI for the evaluation of the nutritional status of children and questionnaire were given to be completed Their ages were between years Stool samples collected were examined using direct wet mount and the formal ether concentration technique The BMI was classified based on children with normal weight and those that are under weight Results Three species of intestinal parasitic infections were identified with overall prevalence of The predominant parasites were Entamoeba histolytica Entamoeba coli and Ascaris lumbricoides The prevalence among sex is in males and in females The children with normal weight were while underweight were The relationship between infectivity and BMI was determined as normal weight P and under weight P P gt Conclusion and Recommendations This study has shown that intestinal parasitic infections are prevalent and have adverse effect on nutritional status of children in Oshodi and there is need for improved nutritional personal and environmental hygiene of these children so as to reduce the infection rate

Soil nematodes in alpine meadows of the Tatra National Park (Slovak Republic)

SummaryThe assemblages of soil nematodes were studied at five alpine meadow sites, 1763-2200 m. a. s. I., in the Tatra National Park in the Slovak Republic. A total of 110 species were distinguished, 19 species were recorded in the Slovak Republic for the first time. The interesting new records are the occurrence of Sphaeronema alni at the elevation of 2003 m a . s. I. and the populations of Coomansus menzeli at four sites. The total numbers of species at individual sites varied from 45 to 72. The most abundant nematode genera were Aglenchus, Plectus. Acrobeloides, Paratylenchus, Eudorylaimus, Helicotylechus, and Aphelenchoides. The total mean abundance ranged from 704 to 2054 × 103ind.m-2and the total mean biomass from 442 to 1531 mg.m-2. The lowest values of the Maturity Indices (ΣMI, Ml) were found at the highest elevation. The significantly highest values of the Plant Parasite Index were at the lowest elevation. The mean values of the of the Enrichment Index varied from 16.3 to 38.4, the mean values of the Structure Index from 64.1 to 85.4. The Structure metabolic footprints were significantly greater at the lowest elevation than at the highest elevation. Cluster Analysis and Principal Component Analysis performed on species presence and absence, genera abundance and genera metabolic footprints showed nematode assemblages at sites of high­er elevations different from those at sites of lower elevations.