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Sample records for gastro-intestinal parasite intensity

  1. Variation in faecal water content may confound estimates of gastro-intestinal parasite intensity in wild African herbivores.

    PubMed

    Turner, W C; Cizauskas, C A; Getz, W M

    2010-03-01

    Estimates of parasite intensity within host populations are essential for many studies of host-parasite relationships. Here we evaluated the seasonal, age- and sex-related variability in faecal water content for two wild ungulate species, springbok (Antidorcas marsupialis) and plains zebra (Equus quagga). We then assessed whether or not faecal water content biased conclusions regarding differences in strongyle infection rates by season, age or sex. There was evidence of significant variation in faecal water content by season and age for both species, and by sex in springbok. Analyses of faecal egg counts demonstrated that sex was a near-significant factor in explaining variation in strongyle parasite infection rates in zebra (P = 0.055) and springbok (P = 0.052) using wet-weight faecal samples. However, once these intensity estimates were re-scaled by the percent of dry matter in the faeces, sex was no longer a significant factor (zebra, P = 0.268; springbok, P = 0.234). These results demonstrate that variation in faecal water content may confound analyses and could produce spurious conclusions, as was the case with host sex as a factor in the analysis. We thus recommend that researchers assess whether water variation could be a confounding factor when designing and performing research using faecal indices of parasite intensity.

  2. Prevalence of gastro-intestinal parasites of backyard chickens (Gallus domesticus) in and around Shimoga.

    PubMed

    Javaregowda, Ananda K; Kavitha Rani, B; Revanna, Suresh Patel; Udupa, Ganesh

    2016-09-01

    The present study was conducted for 1 year from March 2010 to February 2011 to identify gastro-intestinal parasites of backyard chickens and to estimate its prevalence in and around Shimoga, a malnad region of Karnataka. A total of 250 gastro-intestinal tracts were collected from backyard chickens for the detection of gastrointestinal parasites. Among the 250 birds screened, 183 (73.2 %) were found positive for gastrointestinal parasites by gross examination of gastrointestinal tract. Out of 183 positive cases, 94 (51.36 %) were found positive for cestodes, includes 73 (77.6 %) Raillietina tetragona, 12 (12.8 %) Raillietina echinobothrida and 9 (9.6 %) Raillietina cesticillus. Whereas, 53 (28.96 %) were found harbouring nematode parasites includes 33 (62.3 %) had Ascaridia galli, 12 (22.6 %) had Heterakis gallinarum and 8 (15.1 %) had both A. galli and H. gallinarum infection. The remaining 36 (19.67 %) had mixed infections of both cestode and nematode parasites. The microscopic examination of the gut contents and faecal samples showed presence of coccidian oocysts and eggs of A. galli, H. gallinarum and Capillaria spp. respectively.

  3. Gastro-intestinal parasites of the Samango monkey, Cercopithecus mitis, in Natal, South Africa.

    PubMed

    Appleton, C C; Krecek, R C; Verster, A; Bruorton, M R; Lawes, M J

    1994-01-01

    Eight gastro-intestinal tracts of Cercopithecus mitis labiatus from Karkloof, Natal, and 121 fecal samples from C. m. erythrarchus from Cape Vidal, Natal, were examined for helminth parasites and/or their eggs. Fecal samples from six of the C. m. labiatus were examined for protozoan cysts. Five protozoon and six helminth species were identified from C. m labiatus. Most adult worms occurred in the caecum and colon, gut regions which also contained the highest volatile fatty acid levels. The eggs of nine helminth species were recovered from C. m. erythrarchus fecal samples; protozoans were not looked for in these samples.

  4. The point prevalence of gastro-intestinal parasites in calves, sheep and goats in Magadi division, south-western Kenya.

    PubMed

    Maichomo, M W; Kagira, J M; Walker, T

    2004-12-01

    Helminths cause great economic loss in livestock in Africa, and can be categorized as either direct or indirect losses. Arid and semi-arid lands (ASAL) in Kenya comprise 71% of total land area and harbour the largest population of cattle, sheep and goats. However, little information on the distribution and impact of gastro-intestinal (GIT) parasitism in these animals is available. This survey was conducted to establish the prevalence of GIT parasites infecting calves, sheep and goats and their relative importance in Magadi division, which is semi-arid. Faecal samples were obtained directly from the rectum of 109 calves, 133 goats and 20 sheep and submitted to the laboratory for faecal worm egg counts, and coccidial oocysts examination using a modified McMaster method. The significance of differences in mean egg count per gram (epg) between animal species and herds (farms) were assessed using analysis of variance. The overall prevalence of nematodes in the calves, sheep and goats was 69.2%, 80% and 82%, respectively. About 10% of sheep and goats had epgs higher than 1 000, the remainder having light to moderate infections. The overall prevalence of coccidial oocysts in calves, sheep and goats was 30%, 44% and 45%, respectively. Poor productivity in ASAL areas, where nutrition is often poor, is likely to be pronounced in the presence of parasite infections. These findings indicate that viable internal parasite control should be implemented in the study area in order to increase the productivity of the livestock there.

  5. Incidence of gastro-intestinal parasites in horses of Shimoga region, Karnataka state.

    PubMed

    Adeppa, J; Ananda, K J; Krishna Murthy, C M; Satheesha, G M

    2016-09-01

    A study was conducted to ascertain the incidence of gastrointestinal parasites in horses of Shimoga region, to generate the data regarding status of parasitic infections of equines in Karnataka state due to paucity of information. A total of 100 fresh fecal samples of equines were collected and examined by direct and sedimentation method for the detection of parasitic egg/ova. Among 100 samples examined, 84 (84.0 %) were found positive for various gastrointestinal helminths. Out of 84 positive cases, 44 (52.38 %) were found positive for Strongylus spp. eggs, 09 (10.71 %) showed Parascaris equorum eggs, 06 (7.14 %) had Gastrodiscus spp. eggs, 04 (4.76 %) harbored Oxyuris equi and the remaining 21 (25.0 %) had a mixed infection of Strongylus spp., Strongyloides spp. and Gastrodiscus spp.

  6. Does meatiness of pigs depend on the level of gastro-intestinal parasites infection?

    PubMed

    Knecht, Damian; Popiołek, Marcin; Zaleśny, Grzegorz

    2011-05-01

    The aim of the present paper was to determine an influence of the presence and a level of intestine parasites infection on the quality of pork carcass expressed by the content of meat in carcass (meatiness) in pigs. The experimental part of the study was conducted on pigs farm produced in a closed cycle. The population in the study included 120 fattening pigs maintained in two keeping systems: group I--60 individuals kept on slatted floor, and group II--60 individuals kept on deep litter. All the experimental animals were treated in the same manner. The analysed fatteners were slaughtered in Meat Processing Plant when their body mass reached 110 kg, and the post-slaughter assessment was conducted according to the EUROP classification of pigs carcass using the Ultra-Fom 300 device. The study concerning the internal parasites were conducted basing on coproscopic quantitative McMaster method. As a results, the eggs of three nematode taxa were isolated and identified: Oesophagostomum spp., Ascaris suum and Strongyloides ransomi. Overall prevalence of infection of fatteners kept on litter was lower (25%±11.2) as compared to those kept on slatted floor (38.3%±12.6), however the differences were not statistically significant (χ(2)=2.465; df=1; P=0.116). The mean value of meatiness for pigs free from parasites was 53.68, while in the case of infected pigs the meatiness was statistically lower and was 52.12 (t=2.35; P=0.02). The analysed pigs were classified into three categories and conducted analysis of an influence of parasites on meatiness demonstrate the relationship that is statistically significant. The analysis of correlation between meatiness and an average number of helminth eggs also demonstrated the negative, statistically significant, relationship (F=5.52; P=0.020), i.e. in fatteners with higher EPG value the meatiness was lower.

  7. Effect on performance of weanling alpacas following treatments against gastro-intestinal parasites.

    PubMed

    Thomas, Susan M; Morgan, Eric R

    2013-11-15

    Nematodes and coccidia are common parasites of alpacas (Vicugna pacos), and important causes of disease in this increasingly popular livestock species. Endoparasitic infestation is thought to increase at times of natural or imposed stress, and antiparasitic treatments are often administered, although to date there is little evidence regarding their effect. Thirty-one alpaca juvenilles (cria) were divided into four groups at weaning, and received either no treatment as a control (C), fenbendazole anthelmintic (FB), toltrazuril coccidiostat (T), or both treatments (FBT). Body weights and faecal egg/oocyst counts were recorded weekly for six weeks following treatment. Although the prophylactic treatments decreased faecal egg/oocyst counts of the target organisms in the short term, there was no significant difference in egg/oocyst output over the course of the trial from animals given wormer, coccidiostat or both treatments. The group receiving anthelmintic only showed a significant reduction in live weight gain (LWG), with no significant difference in LWG between the other groups. At the conclusion of the trial, 'wormed only' alpacas weighed 3.3% less than at weaning, losing an average 1.3 kg over six weeks, whereas average LWG in the control group was 2.5 kg. Antiparasitics transiently reduced egg/oocyst output but results suggest that further investigation is required on the action of anthelmintics administered to alpaca cria at weaning and their effect on animal health and welfare. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. The effect of grazing forage containing condensed tannins on gastro-intestinal parasite infection and milk composition in Angora does.

    PubMed

    Min, B R; Hart, S P; Miller, D; Tomita, G M; Loetz, E; Sahlu, T

    2005-06-10

    does was higher (P < 0.01) for SL and ROT than for CTF (27, 26 and 23%, respectively). Does that grazed CT-containing forage had considerably lower milk somatic cell counts (SCC) than does grazing non-CT-containing forage. In summary, grazing CT forages reduced FEC, larval development and worm burden, and also appeared to enhance immune response. The CT-containing forage SL reduced gastro-intestinal parasite infections of Angora does and kids.

  9. Ethnoveterinary uses of medicinal plants: a survey of plants used in the ethnoveterinary control of gastro-intestinal parasites of goats in the Eastern Cape Province, South Africa.

    PubMed

    Maphosa, Viola; Masika, Patrick Julius

    2010-06-01

    Conventional drugs have become expensive and therefore unaffordable to resource-limited farmers, causing farmers to seek low cost alternatives, such as use of medicinal plants. In this study, a survey was conducted in order to document information on medicinal plants used by farmers in the control of internal parasites in goats in the Eastern Cape Province. Structured questionnaires and general conversation were used to collect the information from farmers and herbalists. The survey revealed 28 plant species from 20 families that are commonly used in the treatment of gastro-intestinal parasites in goats. The plant family Asphodelaceae was frequent in usage, comprising 21.4% of the plants, and the Aloe was the most utilized species (50%). Leaves were the most frequently used plant parts (45.9%), and decoctions constituted the majority of medicinal preparations (70%). Medicinal plants are generally used in combination with other plants, and/or non-plant substances, but a few plants are used on their own. These medicinal plant remedies are administered orally, mainly by use of bottles and this is done twice in summer at intervals of one month, only once in winter and when need arises thereafter. Some of the mentioned plants have been reported in literature to possess anthelmintic properties, while others possess activities ranging from anti-inflammatory, analgesic, antimicrobial, purgative, anti-edema to immuno-regulation. If their safety and efficacy could be confirmed, these plants could form an alternative cost effective strategy in managing helminthiasis in the province.

  10. A survey of gastro-intestinal parasitic infection in domestic and wild birds in Chittagong and Greater Sylhet, Bangladesh.

    PubMed

    Hoque, Md Ahasanul; Hassan, Mohammad Mahmudul; Haque, Enamul; Shaikat, Amir Hossan; Khan, Shahneaz Ali; Alim, Abdul; Skerratt, Lee Francis; Islam, Ariful; Tun, Hein Min; Dissanayake, Ravi; Day, Tapan Kumar; Debnath, Nitish Chandra; Yamage, Mat

    2014-11-01

    A survey of gastrointestinal parasitic infection as determined by faecal examination was conducted among domestic and wild birds in Bangladesh. Birds were sampled from households, wet markets and wetlands in Chittagong and Greater Sylhet districts during April 2012 to February 2013. Mist nets were used to catch resident wild and migratory birds. The overall prevalence of parasitic infection ranged among locations from 25 to 55% in indigenous domestic ducks (live bird samples=304), 20% in resident wild birds (environmental faecal samples=40) and 40% in migratory birds (live bird samples=35). The prevalence of parasitic infection was significantly higher in indigenous domestic ducks collected during summer (39%) than winter (22%) (p=0.04). In domestic indigenous ducks and Muscovy ducks, both single and multiple types of parasitic infections were found. However, other domestic birds and wild birds often had a single type of parasitic infection. Ascaridia spp. with an average egg load of 50-900, was commonly detected in faecal samples of domestic and wild birds in this study. Other identified parasites were Capillaria spp. and Heterakis spp. both in domestic and wild birds. Improvement of biosecurity measures for household duck farms through educating and motivating household farmers could help mitigate the effects of parasitic infection on production.

  11. Transcriptomic response of red grouse to gastro-intestinal nematode parasites and testosterone: implications for population dynamics.

    PubMed

    Webster, L M I; Paterson, S; Mougeot, F; Martinez-Padilla, J; Piertney, S B

    2011-03-01

    A central issue in ecology is in understanding the relative influences of intrinsic and extrinsic effects on population regulation. Previous studies on the cyclic population dynamics of red grouse (Lagopus lagopus scoticus) have emphasized the destabilizing effects of either nematode parasites or territorial behaviour and aggression. The potential interacting effects of these processes, mediated through density-dependent, environmentally induced alterations of host immunocompetence influencing susceptibility to parasites have not been considered. Male red grouse at high density are more aggressive, associated with increased testosterone, which potentially could lead to reduced immunocompetence at a stage when parasites are most prevalent. This could depress individual condition, breeding performance and survival and thus drive or contribute to overall reductions in population size. Here, we characterize the transcriptomic response of grouse to nematode parasite infection and investigate how this is subsequently affected by testosterone, using a microarray approach contrasting red grouse with high and low parasite load at both high and low testosterone titre. A suite of 52 transcripts showed a significant level of up-regulation to either chronic parasite load or experimental parasite infection. Of these, 51 (98%) showed a reduced level of expression under conditions of high parasite load and high testosterone. The genes up-regulated by parasites and then down-regulated at high testosterone titre were not necessarily associated with immune response, as might be intuitively expected. The results are discussed in relation to the fitness and condition of individual red grouse and factors influencing the regulation of abundance in natural populations. © 2010 Blackwell Publishing Ltd.

  12. Evaluation of gastro-intestinal nematode parasite control strategies for first-season grazing cattle in Sweden.

    PubMed

    Dimander, Sten-Olof; Höglund, Johan; Uggla, Arvid; Spörndly, Eva; Waller, Peter J

    2003-02-13

    A three-year grazing experiment (1998-2000) was conducted with first-season grazing cattle (FSGC) on improved pastures in central-eastern Sweden. Comparison was made between five groups with 10 calves in each group where four of these were set stocked and either (1) untreated, (2) ivermectin bolus treated, (3) subjected to biological control with the nematophagous fungus Duddingtonia flagrans, or (4) treated with a copper wire particle bolus. The fifth treatment was an evasive grazing strategy, whereby untreated calves were turned out onto pasture used by older cattle the previous year and then these calves were moved to silage aftermath in mid-July. To introduce low-levels of parasite infection to the experiment, each animal received a 'priming dose' of approximately 5,000 Ostertagia ostertagi and 5,000 Cooperia oncophora infective third stage larvae immediately prior to the start of the first grazing year of the trial. Results showed that efficient and sustainable parasite control of FSGC was possible to achieve without the use of anthelmintics by using turnout pastures that the previous year had been grazed by older cattle, in combination with a mid-July move to aftermath leys. Biological control also proved beneficial but the efficacy was impaired if high faecal egg counts coincided with rapid dung pat degradation due to heavy rainfall. No indication of parasite control was observed with the copper wire particle bolus. It was also demonstrated that the impact of gastrointestinal (GI) parasitism varied between years and that the level of overwintering contamination is important but likewise, is unpredictable. Although faecal egg counts in 1999 were low, due both to a delayed turnout and drought for the major part of the grazing season, deposited eggs successfully developed to infective larvae and overwintered in large numbers. The population of overwintered infective larvae at the time of turnout in early May played an important role in the course of infection

  13. Prevalence and risk factors for development of hemorrhagic gastro-intestinal disease in veterinary intensive care units in the United Kingdom.

    PubMed

    Swann, James W; Maunder, Christina L; Roberts, Emma; McLauchlan, Gerard; Adamantos, Sophie

    2016-05-01

    To determine the prevalence of hemorrhagic gastro-intestinal (GI) disease developing in dogs and cats admitted for management of non-GI disease in veterinary intensive care units (ICUs). Retrospective study of animals presented between October 2012 and July 2013. Three ICUs located in veterinary teaching hospitals in the United Kingdom. Dogs (n = 272) and cats (n = 94) were consecutively enrolled from 3 ICUs if they were hospitalized in the unit for at least 24 hours. Cases were excluded if they had hemorrhagic GI disease in the 48-hour period before presentation or in the 24-hour period after admission. Cases were also excluded if they suffered skull fracture, epistaxis, or hemoptysis, if they underwent surgical procedures of the GI or upper respiratory tracts, or if they were presented for management of GI disease. Hemorrhagic GI disease was observed in dogs at all 3 units, but at different rates (Center 1: 10.3%, Center 2: 4.8%, Center 3: 2.2%). Hemorrhagic GI disease was not observed in cats at any of the participating centers. Construction of a multivariable logistic regression model revealed that serum albumin concentration, administration of prophylactic gastro-protectant drugs, and institution were significantly associated with the development of hemorrhagic GI disease in dogs. Development of hemorrhagic GI disease and placement of a feeding tube were significantly associated with mortality during the period of hospitalization in dogs. Thirty-seven (13.6%) dogs and 12 (12.8%) cats died or were euthanized while hospitalized, with a higher mortality rate (42.1%) in dogs with hemorrhagic GI disease. Hemorrhagic GI disease does develop in dogs hospitalized for management of non-GI disease, but this phenomenon was not observed in cats. Development of hemorrhagic GI disease appeared to have a significant impact on survival in veterinary ICUs. © Veterinary Emergency and Critical Care Society 2015.

  14. Heritability of resistance to infestation with the body louse, Bovicola ovis, in Romney sheep bred for differences in resistance or resilience to gastro-intestinal nematode parasites.

    PubMed

    Pfeffer, A; Morris, C A; Green, R S; Wheeler, M; Shu, D; Bisset, S A; Vlassoff, A

    2007-12-01

    The inheritance of resistance to louse infestation and the related allergic skin disease, cockle, was examined in Romney lambs. The lambs used in the study were the 2001- and 2004-born progeny of four experimental breeding lines ("Resistant", "Susceptible", "Resilient" and "Control") developed as part of a long-term study of the genetics of host resistance (maintenance of low faecal egg count (FEC) under nematode challenge) or resilience (maintenance of health and productivity under nematode challenge irrespective of FEC) to nematode parasites in sheep. Between 13 and 22 progeny (equally distributed between males and females, where possible) from each of five sires in each line were selected each year for this trial. All lambs (n=701) were examined for lice (Bovicola ovis) before artificial infestation; in 2001 the lambs were free of natural infestation, whilst in 2004 naturally acquired infestation was evident. In November 2001 and May 2002, approximately 60 B. ovis were transferred to each lamb, followed by monitoring at approximately 2-monthly intervals until August 2002. Similar procedures, but with fewer monitoring times, were repeated on the 2004 lambs. Overall, lambs in the Control line were significantly more susceptible to louse infestation and cockle compared with those in the other three lines (P<0.001). Least squares-means (SEM) of log-transformed louse score for the control, resistant, susceptible and resilient lines, respectively, were 2.178 (0.045), 1.499 (0.050), 1.618 (0.050) and 1.587 (0.044), and for cockle score were 1.36 (0.05), 0.76 (0.05), 0.95 (0.05) and 0.78 (0.05). From all progeny together, the heritability of log-transformed louse score was 0.22 (Standard Error (SE) 0.06) in autumn and 0.34 (SE 0.08) in winter, with a value of 0.44 (SE 0.09) when these data were combined. These estimates were similar to those obtained for resistance to gastro-intestinal nematodes in these breeding lines, using log-transformed FECs. Heritability estimates

  15. Prevalence of the gastro-intestinal parasites of domestic chicken Gallus domesticus Linnaeus, 1758 in Tunisia according to the agro-ecological zones.

    PubMed

    Ben Slimane, Badreddine

    2016-09-01

    Helminthosis is a very important disease affecting the poultry industry, especially the traditionally reared free ranging chickens. In Tunisia, the poultry production is considered as the most important source of protein in as much as chickens provide 53 % of animal protein production. The traditionally reared poultry farming system exposes chickens to many types of parasites, however, very little work has been done to establish the extend of helminth infection in Tunisia. The aim of this work is to investigate various aspects of helminth infections. A significant difference (p < 0.01) was found between the prevalence rates of helminth parasites in the different agro-ecological zones. The highest prevalence was observed in lowland areas of northern Tunisia (Siliana district). This suggests that agro-ecology has a major influence on the distribution of helminth parasites. Recovered nematodes included Heterakis spp. (100 %), Ascaridia galli (53.33 %) and Acuaria hamulosa (37 %). The principal cestode species encountered were Hymenolepis spp. (73.33 %) and Raillietina spp. (33.33 %).

  16. Impact of post operative intensity modulated radiotherapy on acute gastro-intestinal toxicity for patients with endometrial cancer: results of the phase II RTCMIENDOMETRE French multicentre trial.

    PubMed

    Barillot, Isabelle; Tavernier, Elsa; Peignaux, Karine; Williaume, Danièle; Nickers, Philippe; Leblanc-Onfroy, Magali; Lerouge, Delphine

    2014-04-01

    Whole "conventional" pelvic irradiation (up to 45-50Gy) following hysterectomy is associated with a high rate of adverse gastro-intestinal (GI) adverse events, of which around 60% correspond to acute grade 2 toxicity. The phase II RTCMIENDOMETRE trial was designed to test the hypothesis that IMRT could reduce the incidence of grade 2 or more acute GI toxicity to less than 30% in patients irradiated post-operatively for an endometrial cancer. Patients with post-operative stage Ib G3, Ic or II endometrial carcinomas with no history of chronic inflammatory bowel disease were eligible. Guidelines for volume delineation and dose prescription were detailed in the protocol. The investigators were advised to use a web-based atlas developed for the RTOG 0418 study. The dose of the vaginal and nodal PTV was 45Gy in 25 fractions. To assess the ability of the participating centres to comply with the protocol guidelines, they were requested to complete a dummy run procedure before inclusion of their 1st patient. GI and genito-urinary (GU) toxicity were graded according to the CTCAE V 3.0 classification and were prospectively recorded every week during irradiation, as well as at time of brachytherapy insertions and during the follow-up visit at week 15 (W15). Special attention was given to note any changes to the grade of adverse events between W5 and W15. From May 2008 to April 2010, 49 patients from 6 centres were recruited for the trial. One patient could not be treated, one patient died of vascular stroke at W3 without toxicity, and 1 patient refused to be followed-up after treatment. Thus, 46 cases were available for analysis at W15. The distribution by stage was as follows: Ib 16.3%, Ic 64.2%, II 20.4%. Thirty six patients (75%) received an additional vaginal vault boost of 6-10Gy delivered by HDR brachytherapy in 1 or 2 fractions. Among the 47 patients who completed IMRT, 27% (95% CI 14.5-39.7%) developed at least 1 GI grade 2 adverse event (diarrhoea in 92% of cases

  17. The gastro-intestinal parasites community of the Przewalski's horse, Equus przewalskii Poljakov, 1881, and the domestic horse in the Chernobyl exclusion zone.

    PubMed

    Slivinska, Kateryna

    2006-01-01

    A diagnostic deworming of 21 Przewalski horses, free-living in the Chernobyl exclusion zone Ukraine, and of six stabled domestic horses, has been conducted eighteen years after the Chernobyl nuclear disaster. This survey yielded 31 species (of 5 families and 3 classes, 28 species of nematodes, 1 species of cestodes, and 2 larvae of botflies). A total 29 and 19 helmith species has been recorded in the Przewalski horse and domestic horse respectively. Only six helmith species were common for the two horse species. Species from the family Strongylidae constituted the dominant helmith group. Four cyathostomine species (Cyathostomum catinatum, Cylicostephanus minutes, C. longibursatus, Cylicocyclus nassatus) formed the majority of helmith parasites both in the Przewalski and domestic horses. The presently reported study revealed that Przewalski's horses keep their typical biological features and high resistance to parasitic infections. A substantial growth of heard was observed as well as good clinical health state of horses. This can be an argument favouring the use of Przewalski horses in re-naturalization of ecological disaster areas.

  18. Exploration of the epidemiological consequences of resistance to gastro-intestinal parasitism and grazing management of sheep through a mathematical model.

    PubMed

    Laurenson, Yan Christian Stephen Mountfort; Kyriazakis, Ilias; Forbes, Andrew Barnet; Bishop, Stephen Christopher

    2012-10-26

    Predicting the impacts of selection for decreased faecal egg count (FEC) (i.e. host resistance) in grazing ruminants is difficult, due to complex interactions between parasite epidemiology, management and host responses. A mathematical model including heritable between lamb variation in host-parasite interactions, Teladorsagia circumcincta epidemiology and anthelmintic drenching, was developed and used to (i) address such interactions and their impact on outcomes including FEC, live weight (LW, kg) and pasture larval contamination (PC, larvae/kg DM), and (ii) investigate how grazing management strategies, aimed at reducing host exposure to infective larvae via pasture moves at 40 day intervals, affect these outcomes. A population of 10,000 lambs was simulated and resultant FEC predictions used to assign the 1,000 lambs with the highest and lowest predicted FEC to 'susceptible' (S) and 'resistant', (R) groups, respectively. The predicted average FEC of the S group was ∼8.5-fold higher than the R group across a grazing season. The R and S groups were then simulated to graze separate pastures (R(sep) and S(sep)); and repeated for 3 grazing seasons to allow predictions to diverge and stabilize. Further, different grazing strategies were superimposed on all groups. PC and average FEC were affected by whether lambs of different resistance genotype grazed together or separately, with differences increasing across grazing seasons. By the third grazing season the average PC of the R(sep) group was reduced by ∼83%, and the S(sep) group was increased by ∼240%, in comparison to the whole population average. Average FEC of the R(sep) group was reduced by ∼40%, and the S(sep) group increased by ∼46% in comparison to the R and S groups, respectively, whilst drenching had little impact on the proportional differences in FEC between groups. Predicted LW was similar for the R and R(sep) groups irrespective of anthelmintic treatment, whilst LW of the S(sep) group was

  19. Gastro-intestinal helminths in white-tailed deer (Odocoileus virginianus) of Illinois.

    PubMed

    Cook, T W; Ridgeway, B T; Andrews, R; Hodge, J

    1979-07-01

    Two deer populations, one in northern Illinois the other in southern Illinois, were examined by necropsy (n = 44 and 40 respectively) for helminth parasites of the gastro-intestinal tract and abdominal cavity. Both herds were parasitized by Apteragia odocoilei, Haemonchus contortus, Gongylonema pulchrum, Setaria yehi, Trichuris ovis, and Moniezia benedeni. Nematodirus sp. was found only in deer of northern Illinois. Ostertagia mossi, Capillaria sp., Cooperia sp., and Oesophagostomum sp. were found only in deer of southern Illinois.

  20. [Forming of gastro-intestinal nematodes fauna of free ranging European bison in Bialowieza Primeval Forest during last 17 years (1984-2001)].

    PubMed

    Drózdz, Jan; Demiaszkiewicz, Aleksander W; Lachowicz, Jacek

    2002-01-01

    28 European bison of both sexes and in different age shot in Białowieza Primeval Forest in January 1984, (10 animals), January 1992 (10 animals) and in January and the beginning of February 2001 (8 animals) have been necropsied. The examined animals in mentioned years were of similar age. There were examined abomasa and duodena of shot animals. All necropsied bison were infected with gastro-intestinal nematodes. The highest intensity of infection with nematodes of abomasum was found in 1992 year and with nematodes of duodenum in 2001 year. In the examined period were found as many as 21 species of gastro-intestinal nematodes, and 15 of them occurred in 1984, 16 in 1992 and 17 in 2001; 12 species, namely: Trichostrongylus axei, T. capricola, Ostertagia ostertagi, O. lyrata, O. leptospicularis, O. kolchida, Spiculopteragia boehmi, Cooperia oncophora, Nematodirus helventianus, N. roscidus, N. europaeus and Aonchotheca bilobata occurred in all 3 examined years. The highest mean intensity of infection and the percentage index of intensity of these 12 species of nematodes showed O. leptospicularis which was 45% to 47% of all Ostertagiinae. Beyond of these 12 species of nematodes which occurred in all examined years, there were found 9 species more: Ostertagia antipini, Spiculopteragia mathevossiani, S. asymmetrica, Mazamastrongylus dagestanicus, Cooperia surnabada, C. punctata, C. pectinata, Haemonchus placei and Ashworthius sidemi. They occurred sporadically and in low density. During the examined period, bison have adapted 10 species of parasites from Cervides. Mazamastrongylus dagestanicus - parasite primary typical for moose, was for the first time found in bison.

  1. [The prevalence of gastro-intestinal nematodes in hair goats of the Sanliurfa region].

    PubMed

    Altaş, Mehtap Gül; Sevgili, Murat; Gökçen, Ahmet; Aksin, Nursel; Bayburs, Hüseyin Cahit

    2009-01-01

    The aim of this study was to determine the prevalence of gastro-intestinal nematodes in hair goats in Sanliurfa region between November 2005 and November 2006. During this period, the alimentary canal from 1 or 2 goats was obtained from the municipal slaughterhouse each week. These were brought into the laboratory and examined for the presence of nematodes. Gastro-intestinal tracts of 100 hair goats were examined. Of these, 83 (83%) were found infected with nematodes. Twenty nematode species were identified in hair goats. A total of 7641 nematodes were collected from infected hair goats. The average number of parasites for each animal was 92.06. The number of nematodes species was found to range from 1-6 in infected hair goats. The listing of 12 nematode species detected, according to their prevalence, was as follows; Marshallagia marshalli (54.21%), Teladorsagia circumcincta (72.40%), T. trifurcata (45.78%), T. occidentalis (14.45%), Haemonchus contortus (39.79%), Gongylonema pulchrum (32.53%), Nematodirus spathiger (33.73%), N. filicollis (13.25%), Trichostrongylus vitrinus (13.25%), Chabertia ovina (25.30%), Trichuris ovis (22.88%) and T. skrjabini (34.93%).

  2. In vitro and in vivo anthelmintic activity of Murraya koenigii against gastro-intestinal nematodes of sheep.

    PubMed

    Molla, Sabir Hossen; Bandyopadhyay, Probir Kumar

    2016-06-01

    The present study have been conducted to evaluate the anthelmintic activity of crude aqueous and crude methanolic leaf extracts of Murraya koenigii. Infection of ruminants with gastro-intestinal (GI) parasite has become a worldwide problem. The parasite causes economic losses in a variety of ways. Previously sheep producers relied heavily on anti-parasitic drugs to control gastro-intestinal parasites of the flocks. But due to misuse of these drugs the parasites become resistant to drugs. Thus created interest in studying medicinal plants as an alternative source of controlling the GI parasites. Adult motility assay (AMA) and egg hatch assay (EHA) have been done for in vitro study, and faecal egg count reduction (FECR) assay have been done for in vivo study. The in vitro study revealed anthelmintic effects of M. koenigii on Haemonchus contortus as evident from their paralytic condition and/or death at eight hour post exposure in different concentrations (12.5, 25, 50 mg/ml) of aqueous and methanolic extracts which exhibit to be dose-dependent. Aqueous and methanolic extracts of M. koenigii were found to have low percent inhibitory effect on egg hatching. It may be concluded that M. koenigii showed significant anthelmintic activity.

  3. Biological control of gastro-intestinal nematodes--facts, future, or fiction?

    PubMed

    Larsen, M; Nansen, P; Grønvold, J; Wolstrup, J; Henriksen, S A

    1997-11-01

    The potential of using fungi to prevent nematodosis caused by parasites with free-living larval stages is well documented today. In this respect Duddingtonia flagrans, a net-trapping, nematode-destroying fungus, appears to be the most promising candidate. Laboratory experiments and in-vivo studies, where fungal spores have survived passage through the gastro-intestinal tract of cattle and horses, plus field studies with cattle, horses and pigs, demonstrate significant reduction in the number of infective larvae that develop in the faecal environment. In field trials this reduction subsequently leads to reduced infectivity of herbage and also reduced worm burdens in grazing animals. A status of the present situation, primarily based upon work performed in Denmark within the last 6-8 years, plus an outlook for practical implementation of an integrated control strategy including the use of nematode-destroying fungi in the future is discussed.

  4. The gastro-intestinal helminth infections of domestic fowl in Dschang, western Cameroon.

    PubMed

    Mpoame, M; Agbede, G

    1995-01-01

    Three hundred and fifty one chickens purchased from the Dschang animal market were examined for gastro-intestinal helminths. Ten species were found with the following prevalences: Heterakis brevispiculum (59.3%), Ascaridia galli (51.6%), Hymenolepis carioca (48.4%), Dispharynx spiralis (20.8%), Tetrameres americana (17.1%), Amoebotaenia cuneata (15.1%), Raillietina tetragona (14.5%), Syngamus trachea (13.7%), Hymenolepis cantaniana (5.7%) and Capillaria contorta (2.0%). Infections were predominantly mixed (93.5%). The infection rates were not influenced by host sex except for A. galli which was more prevalent in cocks. Older chickens showed some resistance to A. cuneata and S. trachea. Parasite prevalence and/or worm burdens were generally higher during the rainy season (April to October).

  5. Prevalence and seasonal changes in the gastro-intestinal helminths of Nigerian goats.

    PubMed

    Nwosu, C O; Ogunrinade, A F; Fagbemi, B O

    1996-12-01

    A total of 120 gastro-intestinal tracts and 960 faecal samples were examined to assess the prevalence and seasonal changes in the gastro-intestinal helminth parasites of Red Sokoto (maradi) goats slaughtered at Ibadan between May 1991 and April 1992. Egg types of strongyles, Strongyloides, Trichuris, Skrjabinema, Dicrocoelium and Moniezia were encountered in 93%, 83%, 44%, 0.9%, 2.3% and 31% of the faecal samples respectively. However, only strongyle, Strongyloides and Trichuris eggs occurred in large numbers and were more common during the rainy season than in the dry season. The parasites recorded and their prevalences were Haemonchus contortus (90.0%), H. ovis (5.0%), Strongyloides papillosus (80.8%), Trichostrongylus colubriformis (78.3%), T. axei (69.2%), Trichuris ovis (72.5%), T. globulosa (38.3%), Oesophagostomum columbianum (67.5%), Cooperia curticei (58.3%) Gaigeria pachyscelis (40.8%), Skrjabinema ovis (5.0%), Nematodirus battus (5.8%), Moniezia expansa (29.2%), M. benedeni (10.0%), Paramphistomum spp. (5.0%) and Cysticercus tenuicollis (33.3%). Haemonchus ovis is reported for the first time in Nigeria. Mixed infections were most prevalent. Young goats were more commonly infected and had higher worm counts than adult goats. Only Haemonchus, Trichostrongylus, Strongyloides and Cooperia spp. occurred in large numbers. Irrespective of the age of the goats, higher worm counts were generally encountered during the rainy season than in the dry season. The results are discussed in relation to the control of helminthiasis in grazing animals in Nigeria.

  6. [Metachronous four primary malignancies in gastro-intestinal tract].

    PubMed

    Bae, Jung Min; Kim, Se Won; Kim, Sang Woon; Song, Sun Kyo

    2009-06-01

    Multiple primary malignancy was reported firstly by Billroth in 1889. Recently, multiple primary malignancies are considered to increase due to improved survival rate of cancer patients, advanced diagnostic tools, and increased use of chemotherapy and radiotherapy. In Korea, several cases of triple primary malignancies were reported. However, four primary malignancies in gastro-intestinal tract was rarely reported. Recently, we experienced a 70 year-old male who was diagnosed with metachronous four primary malignancies in rectum, ascending colon, stomach, and ampulla of Vater. We report this rare case of metachronous four primary malignancies with a review of literature.

  7. Patterns of gastro-intestinal parasites and commensals as an index of population and ecosystem health: the case of sympatric western chimpanzees (Pan troglodytes verus) and guinea baboons (Papio hamadryas papio) at Fongoli, Senegal.

    PubMed

    Howells, Michaela E; Pruetz, Jill; Gillespie, Thomas R

    2011-02-01

    The exponential decline of great apes over the past 50 years has resulted in an urgent need for data to inform population viability assessment and conservation strategies. Health monitoring of remaining ape populations is an important component of this process. In support of this effort, we examined endoparasitic and commensal prevalence and richness as proxies of population health for western chimpanzees (Pan troglodytes verus) and sympatric guinea baboons (Papio hamadryas papio) at Fongoli, Senegal, a site dominated by woodland-savanna at the northwestern extent of chimpanzees' geographic range. The small population size and extreme environmental pressures experienced by Fongoli chimpanzees make them particularly sensitive to the potential impact of pathogens. One hundred thirty-two chimpanzee and seventeen baboon fecal samples were processed using sodium nitrate floatation and fecal sedimentation to isolate helminth eggs, larvae, and protozoal cysts. Six nematodes (Physaloptera sp., Ascaris sp., Stronglyloides fuelleborni, Trichuris sp., an unidentified hookworm, and an unidentified larvated nematode), one cestode (Bertiella sp.), and five protozoans (Iodamoeba buetschlii, Entamoeba coli, Troglodytella abrassarti, Troglocorys cava, and an unidentified ciliate) were detected in chimpanzee fecal samples. Four nematodes (Necator sp., S. fuelleborni, Trichuris sp., and an unidentified hookworm sp.), two trematodes (Shistosoma mansoni and an unidentified fluke), and six protozoans (Entamoeba histolytica/dispar, E. coli, Chilomastix mesnili, Balantidium coli, T. abrassarti, and T. cava) were detected in baboon fecal samples. The low prevalence of pathogenic parasite species and high prevalence of symbiotic protozoa in Fongoli chimpanzees are indicative of good overall population health. However, the high prevalence of pathogenic parasites in baboons, who may serve as transport hosts, highlight the need for ongoing pathogen surveillance of the Fongoli chimpanzee

  8. [A rare case of bone metastasis from gastro-intestinal stromal tumour: place of radiotherapy].

    PubMed

    Heymann, S; Imperiale, A; Schlund-Schoettel, E; Sauer, B; Dourthe, L-M

    2014-01-01

    Gastro-intestinal stromal tumours are the most common mesenchymal neoplasms of the gastrointestinal tract. Their usual metastatic sites are the liver and the peritoneum, but gastro-intestinal stromal tumours rarely metastasize to the bones. We report the case of a 56-year-old male presenting with bone lesions six years after initial surgical resection. We discuss through this paper the possibilities of management of these lesions and the place of radiotherapy.

  9. Adenoviruses in Lymphocytes of the Human Gastro-Intestinal Tract

    PubMed Central

    Roy, Soumitra; Calcedo, Roberto; Medina-Jaszek, Angelica; Keough, Martin; Peng, Hui; Wilson, James M.

    2011-01-01

    Objective Persistent adenoviral shedding in stools is known to occur past convalescence following acute adenoviral infections. We wished to establish the frequency with which adenoviruses may colonize the gut in normal human subjects. Methods The presence of adenoviral DNA in intestinal specimens obtained at surgery or autopsy was tested using a nested PCR method. The amplified adenoviral DNA sequences were compared to each other and to known adenoviral species. Lamina propria lymphocytes (LPLs) were isolated from the specimens and the adenoviral copy numbers in the CD4+ and CD8+ fractions were determined by quantitative PCR. Adenoviral gene expression was tested by amplification of adenoviral mRNA. Results Intestinal tissue from 21 of 58 donors and LPLs from 21 of 24 donors were positive for the presence of adenoviral DNA. The majority of the sequences could be assigned to adenoviral species E, although species B and C sequences were also common. Multiple sequences were often present in the same sample. Forty-one non-identical sequences were identified from 39 different tissue donors. Quantitative PCR for adenoviral DNA in CD4+ and CD8+ fractions of LPLs showed adenoviral DNA to be present in both cell types and ranged from a few hundred to several million copies per million cells on average. Active adenoviral gene expression as evidenced by the presence of adenoviral messenger RNA in intestinal lymphocytes was demonstrated in 9 of the 11 donors tested. Conclusion Adenoviral DNA is highly prevalent in lymphocytes from the gastro-intestinal tract indicating that adenoviruses may be part of the normal gut flora. PMID:21980361

  10. Role of parotid amylase in starch digestion in the gastro-intestinal tracts of diabetic rats.

    PubMed

    Kurahashi, M; Inomata, K

    1989-09-01

    In order for the role of parotid amylase in starch digestion in the gastro-intestinal tracts of diabetic rats to be clarified, this study investigated the effect of parotid-duct ligation on both amylase secretion from the parotid glands and pancreas into the gastro-intestinal tract and on starch digestion in the gastro-intestinal contents during feedings. In both diabetic rats and control rats, parotid-duct ligation reduced amylase activity in both the parotid glands during fasting and in the gastric contents after feeding. The amylase activity in the intestinal contents after feeding was reduced by parotid-duct ligation in the diabetic rats. Starch digestion in the gastro-intestinal tract after feeding was reduced by parotid-duct ligation in the diabetic rats. The results suggest that most of the amylase activity in the gastric contents and a large part of the amylase activity in the intestinal contents are derived from the parotid glands, and that parotid amylase plays an important role in starch digestion in the gastro-intestinal tracts of diabetic rats.

  11. The influence of lactose intolerance and other gastro-intestinal tract disorders on L-thyroxine absorption.

    PubMed

    Ruchała, Marek; Szczepanek-Parulska, Ewelina; Zybek, Ariadna

    2012-01-01

    The preferred treatment for hypothyroidism is oral levothyroxine (LT4) ingestion, in doses that ensure a sustained state of hormonal balance. Many different factors may significantly influence the absorption of LT4, including: interval between the ingestion of the drug and the last meal, eating habits, and different functional and organic pathologies of the gastro-intestinal tract. The main purpose of this paper is to review and systematise the available literature on the subject of the influence of different malabsorption syndromes on the effectiveness of LT4 preparations. The need to use high LT4 doses in the substitutional treatment of hypothyroidism is often the very first sign of one of the pathologies that are connected with malabsorption syndrome, which might have been asymptomatic and undiagnosed previously. Patients who require more than 2 μg/kg body weight of LT4 per day, with constantly increased thyrotropin level, should be diagnosed with the suspicion of pseudomalabsorption or real absorption disorder. An LT4 absorption test, using high doses of LT4, may be useful in the diagnosis of pseudomalabsorption. After excluding non-compliance, the differential diagnosis should include such disorders as lactose intolerance, coeliac disease, atrophic gastritis, Helicobacter pylori infection, bowel resection, inflammatory bowel disease, and parasite infection. Where there is a diagnosis of lactose intolerance, both a low lactose diet and a lactose-free LT4 preparation should be administered to restore euthyroidism or make it possible to decrease the dose of the LT4 preparation. In coeliac disease, a gluten-free diet usually allows a normalisation of the need for LT4, as do eradication of the H. pylori infection or parasite colonisation. In cases of atrophic gastritis or inflammatory bowel disease, treating the underlying diseases and regaining the state of remission may improve the absorption of LT4. In patients after gastro-intestinal tract surgery, a dose of

  12. [Organization-methodical aspects of health care delivery to the patients with acute gastro-intestinal hemorrhage].

    PubMed

    Rachkevych, S L; Lemishko, B B

    2011-04-01

    The analysis of organization-methodic work, done with an active participation of academician M. P. Pavlovskiy, for establishment of a Lviv City Center for the treatment of patients, suffering an acute gastro-intestinal hemorrhage, was conducted. During 25 years of the Center activity the organization, diagnostic and treatment and rehabilitation approaches for an acute gastro-intestinal hemorrhage treatment have changed essentially.

  13. Parent-Reported Gastro-Intestinal Symptoms in Children with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Chandler, Susie; Carcani-Rathwell, Iris; Charman, Tony; Pickles, Andrew; Loucas, Tom; Meldrum, David; Simonoff, Emily; Sullivan, Peter; Baird, Gillian

    2013-01-01

    The objective of this study is to investigate whether parentally-reported gastro-intestinal (GI) symptoms are increased in a population-derived sample of children with autism spectrum disorders (ASD) compared to controls. Participants included 132 children with ASD and 81 with special educational needs (SEN) but no ASD, aged 10-14 years plus 82…

  14. Parent-Reported Gastro-Intestinal Symptoms in Children with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Chandler, Susie; Carcani-Rathwell, Iris; Charman, Tony; Pickles, Andrew; Loucas, Tom; Meldrum, David; Simonoff, Emily; Sullivan, Peter; Baird, Gillian

    2013-01-01

    The objective of this study is to investigate whether parentally-reported gastro-intestinal (GI) symptoms are increased in a population-derived sample of children with autism spectrum disorders (ASD) compared to controls. Participants included 132 children with ASD and 81 with special educational needs (SEN) but no ASD, aged 10-14 years plus 82…

  15. [Gastro-intestinal involvement in non Hodgkin's lymphomas, 31 cases (author's transl)].

    PubMed

    Najman, A; Gorin, N C; Barranger, C; Duhamel, G

    1977-11-12

    Gastro-intestinal involvement is a distinctive feature of non-Hodgkin's lymphomas. 31 cases are reported among 200 cases on NHL observed between 1960 and 1976. Multiple involvement appeared in 61%; a diffuse histological pattern is frequent (67%). The relapse of primary isolated gastro-intestinal localization (always) affected extra-digestive tissues (nodes, cavum). Chemotherapy is the mainstay of treatment COP, COAP and MOCA. Surgery is associated in localized involvement or in case of obstruction. High energy radiation therapy is indicated only in lymphosarcomas: -- to residual tumor after chemotherapy--in localized involvement diffuse on all the abdomen at 25 grays after surgery and a brief course of chemotherapy versus surgery and long course of chemotherapy alone.

  16. The gastro-intestinal tract as the major site of biological action of dietary melanoidins.

    PubMed

    Tagliazucchi, Davide; Bellesia, Andrea

    2015-06-01

    Emerging evidence from laboratory researches has highlighted the bioactivity of food melanoidins and melanoproteins. Whilst such studies have been carried out with different in vitro systems, information about melanoidins absorption and bio-availability are scarce. However, they are generally considered as poorly absorbable and bio-available compounds. Therefore, we present a review in which the gastro-intestinal tract is hypothesized to be the main site of action of food melanoidins and melanoproteins biological activity. We described recent data supporting this hypothesis both in vitro model systems and in vivo. Importantly, we focused this review only on the effect of melanoidins and melanoproteins extracted from food. Most of the studies had been carried out using water-soluble carbohydrate-based melanoidins isolated from different food sources (beer, barley coffee, coffee). In bakery products, melanoidins are protein-based structure (melanoproteins) which are largely insoluble in water. Dietary melanoidins and melanoproteins have been demonstrated to exert in vitro antioxidant and metal chelating ability in the gastro-intestinal tract reducing the formation of lipid hydroperoxides and advanced lipid oxidation end products during the digestion of meat. The reduction in the formation of these pro-atherogenic compounds has been shown to be followed by a decrease in their absorption in human volunteers. Food melanoidins have also shown in vitro anti-caries and prebiotic activities. We conclude by underlining the possible role of food melanoidins in the prevention of gastro-intestinal tract cancers. We hope this review will stimulate further research on food melanoidins and their biological activities in the gastro-intestinal tract.

  17. A divergent picornavirus from a turkey with gastro-intestinal disease

    USDA-ARS?s Scientific Manuscript database

    A novel picornavirus, turkey avisivirus (TuASV), was identified from the feces of turkeys (Meleagris gallopavo) with gastro-intestinal disease from a farm in Indiana, USA. Its genome organization is 5’UTR**IRES-II[VP0,VP3,VP1,2A,2B,2C,3A,3B,3Cpro,3Dpol]3’UTR-poly(A). TuASV only shares 34% (P1), 36% ...

  18. The efficacy of formulations of triclabendazole and ivermectin in combination against liver fluke (Fasciola hepatica) and gastro-intestinal nematodes in cattle and sheep and sucking lice species in cattle.

    PubMed

    Stevenson, C R; Mahoney, R H; Fisara, P; Strehlau, G; Reichel, M P

    2002-11-01

    To assess the efficacy of two formulations of triclabendazole and ivermectin in combination against liver fluke (Fasciola hepatica), gastro-intestinal nematodes and sucking louse species in cattle and sheep. A study of 540 cattle and 428 sheep at 18 sites throughout Victoria and New South Wales was undertaken. At each site, one group of cattle or sheep was treated with a combined formulation (Fasimec Cattle or Fasimec Sheep), another received ivermectin and triclabendazole separately. In trials on lice infestation, an additional group remained untreated. Samples for faecal egg counts were collected on days -7, 0 (treatment day), +7, +14 and +21 after treatment. Lice assessments were carried out on days -7, 0, +7, +14, +28, +42 and +56. Both treatments were highly efficacious (> 98% efficacy) against liver fluke in cattle and sheep, against three sucking lice species of cattle and against gastro-intestinal nematodes in sheep. There was also no significant difference between treatments in efficacy. Against gastro-intestinal nematodes, Fasimec Cattle was significantly (P < 0.01) more effective than the separately applied ivermectin and triclabendazole treatment. Mean efficacy for the Fasimec Cattle and Ivomec/Fasinex 120 groups respectively, was 97.6% and 94.2% on Day +7, 98.9% and 91% on Day +14 and 98.5% and 92.6% on Day +21. The efficacy of Fasimec' Cattle and Fasimec Sheep was at least equal to that of currently registered products (with the same active ingredients) used to control these parasites.

  19. [Gastro-intestinal helminths detected by fecal examination in stray dogs in the Aydin province].

    PubMed

    Unlü, Hakki; Eren, Hasan

    2007-01-01

    Fecal specimens of a total of 200 dogs were examined by native, Fulleborn's floatation and Benedek's sedimentation methods to determine the prevalence of gastro-intestinal helminth infections in stray dogs in the Aydin Municipality Animal Shelter and the Kuşadasi Municipality Animal Shelter. Helminth infections were encountered in 82 (41%) of the fecal samples examined. One cestode egg and four nematode eggs were found in the infected fecal samples. The helminth eggs found were identified as follows: Taenia spp. (7.5%), Toxacara spp. (20%), Toxascaris leonina (1%), Uncinaria stenocephala (21%) and Trichuris vulpis (1.5%). No trematode eggs and nematode larvae were found in this study.

  20. Endoscopic ultrasonography: Transition towards the future of gastro-intestinal diseases

    PubMed Central

    De Lisi, Stefania; Giovannini, Marc

    2016-01-01

    Endoscopic ultrasonography (EUS) is a technique with an established role in the diagnosis and staging of gastro-intestinal tumors. In recent years, the spread of new devices dedicated to tissue sampling has improved the diagnostic accuracy of EUS fine-needle aspiration. The development of EUS-guided drainage of the bilio-pancreatic region and abdominal fluid collections has allowed EUS to evolve into an interventional tool that can replace more invasive procedures. Emerging techniques applying EUS in pancreatic cancer treatment and in celiac neurolysis have been described. Recently, confocal laser endomicroscopy has been applied to EUS as a promising technique for the in vivo histological diagnosis of gastro-intestinal, bilio-pancreatic and lymph node lesions. In this state-of-the-art review, we report the most recent data from the literature regarding EUS devices, interventional EUS, EUS-guided confocal laser endomicroscopy and EUS pancreatic cancer treatment, and we also provide an overview of their principles, clinical applications and limitations. PMID:26855537

  1. In Vitro Model Simulating Gastro-Intestinal Digestion in the Pediatric Population (Neonates and Young Infants).

    PubMed

    Kamstrup, Danna; Berthelsen, Ragna; Sassene, Philip Jonas; Selen, Arzu; Müllertz, Anette

    2017-02-01

    The focus on drug delivery for the pediatric population has been steadily increasing in the last decades. In terms of developing in vitro models simulating characteristics of the targeted pediatric population, with the purpose of predicting drug product performance after oral administration, it is important to simulate the gastro-intestinal conditions and processes the drug will encounter upon oral administration. When a drug is administered in the fed state, which is commonly the case for neonates, as they are typically fed every 3 h, the digestion of the milk will affect the composition of the fluid available for drug dissolution/solubilization. Therefore, in order to predict the solubilized amount of drug available for absorption, an in vitro model simulating digestion in the gastro-intestinal tract should be utilized. In order to simulate the digestion process and the drug solubilization taking place in vivo, the following aspects should be considered; physiologically relevant media, media volume, use of physiological enzymes in proper amounts, as well as correct pH and addition of relevant co-factors, e.g., bile salts and co-enzymes. Furthermore, physiological transit times and appropriate mixing should be considered and mimicked as close as possible. This paper presents a literature review on physiological factors relevant for digestion and drug solubilization in neonates. Based on the available literature data, a novel in vitro digestion model simulating digestion and drug solubilization in the neonate and young infant pediatric population (2 months old and younger) was designed.

  2. Acute Upper Gastro-Intestinal Bleeding in Morocco: What Have Changed?

    PubMed Central

    Timraz, A.; Khannoussi, W.; Ajana, F. Z.; Essamri, W.; Benelbarhdadi, I.; Afifi, R.; Benazzouz, M.; Essaid, A.

    2011-01-01

    Objective. In the present study, we aimed to investigate epidemiological, clinical, and etiological characteristics of acute upper gastro-intestinal bleeding. Materials and Methods. This retrospective study was conducted between January 2003 and December 2008. It concerned all cases of acute upper gastroduodenal bleeding benefited from an urgent gastro-intestinal endoscopy in our department in Morocco. Characteristics of patients were evaluated in terms of age, gender, medical history, presenting symptoms, results of rectal and clinical examinations, and endoscopy findings. Results. 1389 cases were registered. As 66% of the patients were male, 34% were female. Mean age was 49. 12% of patients had a history of previous hemorrhage, and 26% had a history of NSAID and aspirin use. Endoscopy was performed in 96%. The gastroduodenal ulcer was the main etiology in 38%, followed by gastritis and duodenitis in 32.5%. Conclusion. AUGIB is still a frequent pathology, threatening patients' life. NSAID and aspirin are still the major risk factors. Their impact due to peptic ulcer remains stable in our country. PMID:21991509

  3. Metabolomics as a Functional Tool in Screening Gastro Intestinal Diseases: Where are we in High Throughput Screening?

    PubMed

    Gundamaraju, Rohit; Vemuri, Ravichandra; Eri, Rajaraman; Ishiki, Hamilton M; Coy-Barrera, Ericsson; Yarla, Nagendra Sastry; Dos Santos, Sócrates Golzio; Alves, Mateus Feitosa; Barbosa Filho, José Maria; Diniz, Margareth F F M; Scotti, Marcus T; Scotti, Luciana

    2017-01-01

    Identifying novel bio markers in gastro intestinal disease is a promising method where a comprehensive analysis of the metabolome is performed. Metabolomics has evolved enormously in the past decade, paving a path in gastro intestinal disease research, especially diseases which lead to high morbidity and mortality. Metabolomics involves identifying metabolites such as anti-oxidants, and amino acids etc., which are screened in the urine, feces and tissue samples. Certain cases employ advanced tools like GC-MS, 1HNMR and GC-MS/SPME which reveal valuable information concerning disease severity and differentiation. In light of escalating health care costs and risky invasive procedures, metabolomics can be chosen as a safe yet precise method for screening diseases like ulcerative colitis, Crohns' disease, celiac disease, and gastro intestinal cancers. The present review focuses on major advancements in gastro intestinal metabolomics, giving attention to which parameters are assessed, and to recent changes in metabolite analysis. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  4. [Course system of the Working Group for Gastro-intestinal Surgery Davos].

    PubMed

    Saeger, H-D; Kersting, S; Vogelbach, P; Hamel, C; Oertli, D; Hölscher, A; Thomas, W E G

    2010-01-01

    Training in technical skills is essential for advanced surgical education. Training is moving more and more from the operating room to surgical training laboratories. A crucial impulse for this development came from Davos, where the first skills course was organized in 1984 after the formation of the Working Group for Gastro-intestinal (GI) Surgery (AGC Davos). Since this first course more than 5,000 residents have successfully completed the GI skills training course in Davos and many of the alumni are themselves teaching surgery today. The level and quality of this course has remained stable for 27 years on a high quality level although teaching has continuously been adjusted to modern techniques. The language of this international workshop is English. The number of applications exceeds the course capacity every year, which is an indication for the need of such training courses and should be principally included into the skills curriculum for surgeons.

  5. Gastro-intestinal basidiobolomycosis in a 2-year-old boy: dramatic response to potassium iodide.

    PubMed

    Sanaei Dashti, Anahita; Nasimfar, Amir; Hosseini Khorami, Hossein; Pouladfar, Gholamreza; Kadivar, Mohammad Rahim; Geramizadeh, Bita; Khalifeh, Masoomeh

    2016-07-04

    Gastro-intestinal basidiobolomycosis (GIB) is a rare fungal infection caused by Basidiobolus ranarum. Treatment includes surgical resection and long-term antifungal therapy. A 2.5-year-old boy presented with a 10-day history of abdominal pain, fever and diarrhoea, and a palpable abdominal mass was detected. Resection was undertaken and histology confirmed basidiobolomycosis. Treatment with amphotericin B and itraconazole was commenced, but the infection progressed and spread to involve the intestines, liver, ribs and lung, and also the abdominal wall after 6 months, requiring four operative procedures. Because of unresponsiveness to amphotericin and itraconazole, oral potassium iodide was added which resulted in complete resolution of the infection. Potassium iodide is an essential component of the treatment of systemic B. ranarum.

  6. Establishment of gastro-intestinal helminth infections in free-range chickens: a longitudinal on farm study.

    PubMed

    Wongrak, Kalyakorn; Daş, Gürbüz; Moors, Eva; Sohnrey, Birgit; Gauly, Matthias

    2014-01-01

    The objective of this study was to monitor establishment and development of gastro-intestinal helminth infections in chickens over two production years (PY) on a free-range farm in Lower Saxony, Germany. The data were collected between July 2010 and June 2011 (PY1) and July 2011 and January 2013 (PY2), respectively. During PY1, Lohmann Brown classic (LB classic, N = 450) was tested, while in PY2 two different genotypes (230 LB classic, 230 LB plus) were used. The hens were kept in two mobile stalls that were moved to a new position at regular intervals. In both PY1 and PY2, 20 individual faecal samples per stall were randomly collected at monthly intervals in order to calculate the number of internal parasite eggs per gram of faeces (EPG). At the end of the laying periods, approximately 10% (N = 42) or more than 50% (N = 265) of hens were subjected to post-mortem parasitological examinations in PY1 and PY2, respectively. No parasite eggs were found in the faecal samples during PY1, whereas almost all of the hens (97.6%) were infected with Heterakis gallinarum (36 worms/hen) at the end of the period. In PY2, nematode eggs in faeces were found from the third month onwards at a low level, increasing considerably towards the final three months. There was no significant difference between the two genotypes of brown hens neither for EPG (P = 0.456) or for overall prevalence (P = 0.177). Mortality rate ranged from 18.3 to 27.4% but did not differ significantly between genotypes or production years. Average worm burden was 207 worms/hen in PY2. The most prevalent species were H. gallinarum (98.5%) followed by Ascaridia galli (96.2%) and Capillaria spp. (86.1%). Furthermore, three Capillaria species, C. obsignata, C. bursata and C. caudinflata were differentiated. In conclusion chickens kept on free-range farms are exposed to high risks of nematode infections and have high mortality rates with no obvious link to parasite infections. Once the farm environment is contaminated

  7. [Gastro-intestinal neuroectodermal tumor (GNET): A case report of a small intestine tumor with hepatic metastases].

    PubMed

    Kervarrec, Thibault; Lecointre, Claire; Kerdraon, Rémy; Bens, Guido; Piquard, Arnaud; Michenet, Patrick

    2015-12-01

    The gastro-intestinal neuroectodermal tumor (GNET) is a rare sarcoma of the digestive tract, which was recently recognised. The knowledge of the morphological, immunohistochemical and molecular diagnostic criteria is necessary to not mistake it for the metastasis of a melanoma or for another sarcoma of the digestive tract as the gastro-intestinal clear cells sarcoma or the malignant peripheral nervous system tumor (MPNST). We report the case of a 41-year-old patient with a GNET of the small intestine with hepatic metastasis. The histological examination showed a diffuse proliferation of epithelioid cells, which only express PS100. The presence EWSR1-ATF1 gene fusions with any melanocytic differentiation leads to the diagnosis of GNET.

  8. Open trial of cimetidine in the prevention of upper gastro-intestinal haemorrhage in patients with severe intracranial injury.

    PubMed

    Mouawad, E; Deloof, T; Genette, F; Vandesteene, A

    1983-01-01

    The present study evaluates the efficacy of Cimetidine in the prevention of clinically important gastro-intestinal haemorrhage in patients suffering from severe head injury. Fifty patients (39 males and 11 females) were included in the study. We excluded from the trial patients on anticoagulant therapy or concomitant non-steroid anti-inflammatory agents, pregnant and lactating women, and patients with previous histories of peptic ulcer disease.

  9. Novel drugs to ameliorate gastro-intestinal normal tissue radiation toxicity in clinical practice: what is emerging from the laboratory

    PubMed Central

    Berbée, Maaike; Hauer-Jensen, Martin

    2013-01-01

    Purpose of the review To give an overview of promising novel agents under development for the prevention and reduction of gastro-intestinal radiation injury. Recent findings Currently, several novel agents are being tested as drugs to prevent or reduce gastro-intestinal radiation injury. These drugs may not only prevent injury, but may also mitigate toxicity, i.e. reduce injury after radiation exposure has occurred. Promising novel agents include the somatostatin analogue SOM230, growth factors, agents acting on the toll-like receptor 5 pathway, endothelial protectants, and the vitamin E analogue γ-tocotrienol. Summary Gastro-intestinal radiation injury is the most important dose limiting factor during radiotherapy of the abdomen or pelvis. It may severely affect quality of life both during radiotherapy treatment and in cancer survivors. To date, there are no agents that can prevent or reduce intestinal radiation injury. Hence, there is an urgent need for the development of novel drugs to ameliorate intestinal toxicity during and after radiotherapy. This review summarizes several agents that have been shown to reduce intestinal radiation injury in animals. Further research is needed to investigate their safety and efficacy in patients receiving radiotherapy for abdominal or pelvic tumours. PMID:22228028

  10. Worm control practice against gastro-intestinal parasites in Norwegian sheep and goat flocks

    PubMed Central

    2011-01-01

    Background Anthelmintic treatment is the most common way of controlling nematode infections in ruminants. However, several countries have reported anthelmintic resistance (AR), representing a limitation for sustainable small ruminant production. The knowledge regarding worm control management represents a baseline to develop a guideline for preventing AR. The aim of the present study was therefore to improve our knowledge about the worm control practices in small ruminant flocks in Norway. Methods A questionnaire survey regarding worm control practices was performed in small ruminant flocks in Norway. Flocks were selected from the three main areas of small ruminant farming, i.e. the coastal, inland and northern areas. A total of 825 questionnaires, comprising 587 sheep flocks (return rate of 51.3%) and 238 goat flocks (52.6%) were included. Results The results indicated that visual appraisal of individual weight was the most common means of estimating the anthelmintic dose used in sheep (78.6%) and goat (85.1%) flocks. The mean yearly drenching rate in lambs and ewes were 2.5 ± 1.7 and 1.9 ± 1.1, respectively, whereas it was 1.0 (once a year) in goats. However, these figures were higher in sheep in the coastal area with a rate of 3.4 and 2.2 in lambs and ewes, respectively. Benzimidazoles were the predominant anthelmintic class used in sheep flocks (64.9% in 2007), whereas benzimidazoles and macrocyclic lactones were both equally used in dairy goat flocks. In the period of 2005-2007, 46.3% of the sheep flocks never changed the anthelmintic class. The dose and move strategy was practiced in 33.2% of the sheep flocks. Conclusions The present study showed that inaccurate weight calculation gives a risk of under-dosing in over 90% of the sheep and goat flocks in Norway. Taken together with a high treatment frequency in lambs, a lack of anthelmintic class rotation and the common use of a dose-and-move strategy, a real danger for development of anthelmintic resistance (AR) seems to exist in Norwegian sheep and goat flocks. This risk seems particularly high in coastal areas where high treatment frequencies in lambs were recorded. PMID:21569497

  11. A mechanism-based approach for absorption modeling: the Gastro-Intestinal Transit Time (GITT) model.

    PubMed

    Hénin, Emilie; Bergstrand, Martin; Standing, Joseph F; Karlsson, Mats O

    2012-06-01

    Absorption models used in the estimation of pharmacokinetic drug characteristics from plasma concentration data are generally empirical and simple, utilizing no prior information on gastro-intestinal (GI) transit patterns. Our aim was to develop and evaluate an estimation strategy based on a mechanism-based model for drug absorption, which takes into account the tablet movement through the GI transit. This work is an extension of a previous model utilizing tablet movement characteristics derived from magnetic marker monitoring (MMM) and pharmacokinetic data. The new approach, which replaces MMM data with a GI transit model, was evaluated in data sets where MMM data were available (felodipine) or not available (diclofenac). Pharmacokinetic profiles in both datasets were well described by the model according to goodness-of-fit plots. Visual predictive checks showed the model to give superior simulation properties compared with a standard empirical approach (first-order absorption rate + lag-time). This model represents a step towards an integrated mechanism-based NLME model, where the use of physiological knowledge and in vitro–in vivo correlation helps fully characterize PK and generate hypotheses for new formulations or specific populations.

  12. Association between gastro-intestinal symptoms and menstruation in patients with ileal pouches

    PubMed Central

    Bharadwaj, Shishira; Wu, Xian-rui; Barber, Matthew D.; Queener, Elaine; Graff, Lesley; Shen, Bo

    2014-01-01

    Background and aims: Gastro-intestinal (GI) symptoms are often experienced by healthy women during menstruation. An increased frequency of GI symptoms during menses has also been reported in women with irritable bowel syndrome or inflammatory bowel disease (IBD); however, IBD patients with restorative proctocolectomy and ileal pouch-anal anastomoses (IPAA) have not been studied. We aimed to examine the association between GI symptoms before and during menses in patients with IPAA, and to assess factors for exacerbation of GI symptoms in those patients. Methods: Adult women recorded in the Pouchitis Registry were invited to participate in a mailed survey. Participants reported on GI symptoms 1–5 days prior to- (pre-menses) and during the days of their menses in recent months. Demographic and clinical variables were obtained through the survey and chart review. Results: One hundred and twenty-eight (21.3%) out of 600 women with IPAA responded to the survey questionnaire. Forty-three (33.5%) were excluded for reasons including post-menopausal (n = 25), hysterectomy (n = 14) and use of contraceptives (n = 4). Abdominal pain (P = 0.001), diarrhea (P = 0.021), and urgency (P = 0.031) were more commonly reported during menses than pre-menses by the participants. Only a history of painful menses was significantly associated with increased GI symptoms during menses for patients with ileal pouch (odds ratio = 5.67; 95% confidence interval: 1.41–22.88; P = 0.015). Conclusion: GI symptoms such as abdominal pain, diarrhea, and urgency are commonly associated with menses in patients with ileo-anal pouch. Painful menses may be associated with worsening of GI symptoms. PMID:25016379

  13. Stability and activity of an Enterobacter aerogenes-specific bacteriophage under simulated gastro-intestinal conditions.

    PubMed

    Verthé, K; Possemiers, S; Boon, N; Vaneechoutte, M; Verstraete, W

    2004-09-01

    A bacteriophage, designated UZ1 and showing lytic activity against a clinically important strain (BE1) of Enterobacter aerogenes was isolated from hospital sewage. The stability and lytic activity against this strain under simulated gastro-intestinal conditions was evaluated. After addition of bacteriophage UZ1 to a liquid feed at gastric pH 2, the phage was immediately inactivated and could not be recovered. However, by use of an antacid to neutralize stomach acidity, no significant changes in phage titer were observed after 2 h incubation at 37 degrees C. After supplementing pancreatic juice and further incubation for 4 h, the phage titer remained stable. The persistence of UZ1 in a mixed microbial ecosystem that was representative for the large intestine was monitored using an in vitro simulation of the human intestinal microbial ecosystem. A pulse administration of bacteriophage UZ1 at a concentration of 10(5) plaque-forming units (PFU)/ml to reactor 3 (which simulates the ascending colon) showed that, in the absence of the host, bacteriophage UZ1 persisted for 13 days in the simulated colon, while the theoretical washout was calculated at 16 days. To assess its lytic activity in an intestinal microbial ecosystem, a green fluorescent protein (gfp)-labeled E. aerogenes BE1 strain was constructed and gfp-specific primers were designed in order to quantify the host strain using real-time PCR. It was observed that bacteriophage UZ1 was able to replicate and showed lytic activity against E. aerogenes BE1/ gfp in an intestinal microbial ecosystem. Indeed, after 17 h a 2 log unit reduction of E. aerogenes BE1/ gfp was measured as compared with the assay without bacteriophage UZ1, while the phage titer increased by 2 log units at an initial multiplicity of infection of 0.07 PFU/colony-forming unit. This is the first report of an in vitro model to study bacteriophage activity in the complex intestinal microbial community.

  14. Self-medication with tannin-rich browse in goats infected with gastro-intestinal nematodes.

    PubMed

    Amit, M; Cohen, I; Marcovics, A; Muklada, H; Glasser, T A; Ungar, E D; Landau, S Y

    2013-12-06

    Primates self-medicate to alleviate symptoms caused by gastro-intestinal nematodes (GIN) by consuming plants that contain secondary compounds. Would goats display the same dietary acumen? Circumstantial evidence suggests they could: goats in Mediterranean rangelands containing a shrub - Pistacia lentiscus - with known anthelmintic properties consume significant amounts of the shrub, particularly in the fall when the probability of being infected with GIN is greatest, even though its tannins impair protein metabolism and deter herbivory. In order to test rigorously the self-medication hypothesis in goats, we conducted a controlled study using 21 GIN-infected and 23 non-infected goats exposed to browse foliage from P. lentiscus, another browse species - Phillyrea latifolia, or hay during the build-up of infection. GIN-infected goats showed clear symptoms of infection, which was alleviated by P. lentiscus foliage but ingesting P. lentiscus had a detrimental effect on protein metabolism in the absence of disease. When given a choice between P. lentiscus and hay, infected goats of the Mamber breed showed higher preference for P. lentiscus than non-infected counterparts, in particular if they had been exposed to Phillyrea latifolia before. This was not found in Damascus goats. Damascus goats, which exhibit higher propensity to consume P. lentiscus may use it as a drug prophylactically, whereas Mamber goats, which are more reluctant to ingest it, select P. lentiscus foliage therapeutically. These results hint at subtle trade-offs between the roles of P. lentiscus as a food, a toxin and a medicine. This is the first evidence of self-medication in goats under controlled conditions. Endorsing the concept of self-medication could greatly modify the current paradigm of veterinary parasitology whereby man decides when and how to treat GIN-infected animals, and result in transferring this decision to the animals themselves. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Polyphenols from Pistacia lentiscus and Phillyrea latifolia impair the exsheathment of gastro-intestinal nematode larvae.

    PubMed

    Azaizeh, H; Halahleh, F; Abbas, N; Markovics, A; Muklada, H; Ungar, E D; Landau, S Y

    2013-01-16

    The infection of grazing ruminants with gastro-intestinal nematodes (GINs) is a severe problem in the Middle East. However, goats that graze the south-western slopes of the Carmel Heights in Israel have very low faecal egg counts, despite high grazing density. We hypothesized that polyphenols from Pistacia lentiscus L. and/or Phillyrea latifolia L. - both prevalent woody species of the region that are consumed by goats - have anthelmintic bioactivity. We tested this hypothesis by using the larval exsheathment inhibition assay (LEIA). Extracts were prepared from leaves of either plant species using 70% ethanol (E70), 100% ethanol (E100), or boiling water (W). Larvae were incubated in a phosphate-buffered saline solution with or without plant extract (1200μg/ml) and then exposed to an exsheathment solution expected to elicit 100% exsheathment after one hour. All extraction methods of P. lentiscus were highly effective at inhibiting larval exsheathment, but higher potency was found for the E70 than for E100 extraction method, while W was intermediate. Only the E70 extract of P. latifolia was highly effective relative to the control. The E70 extract of P. lentiscus had more than 7 times the potency of the E70 extract of P. latifolia. Irrespective of solvent and tannin-equivalent used, P. lentiscus contained more than double the quantity of total polyphenols than P. latifolia. The polyphenols of P. lentiscus consisted mainly of galloyl derivatives (63.6%), flavonol glucosides (28.6%), and catechin (7.8%). In P. latifolia, oleuropein and its derivative tyrosol accounted for 49.3 and 23.1% of phenolics, respectively, the remainder being flavones (luteolin and quercetin) and their glucoside derivatives. Results of the LEIA test suggest that extracts of tannin-rich plants interfere with the very early stage of host invasion and that high concentration of galloylated derivatives may explain anthelmintic activity.

  16. A rare cause of gastro-intestinal hemorrhage in a patient with a Roux-en-Y gastric bypass

    PubMed Central

    Cartabuke, Richard H.; Mehta, Paresh P.; El-Hayek, Kevin; Henderson, J. Michael; Burke, Carol A.

    2016-01-01

    This case illustrates a rare cause of gastro-intestinal bleeding following bariatric surgery. Though it is essential to rule out common causes of variceal formation accompanied by intermittent, profuse bleeding, there should be a high degree of suspicion of this rare etiology in patients who have previously undergone alteration of their anatomy, especially Roux-en-Y gastric bypass (RYGB). The case emphasizes the need for a multidisciplinary medical-surgical team in evaluating and treating patients who present with complex intra-abdominal pathology. PMID:25155016

  17. A rare cause of gastro-intestinal hemorrhage in a patient with a Roux-en-Y gastric bypass.

    PubMed

    Cartabuke, Richard H; Mehta, Paresh P; El-Hayek, Kevin; Henderson, J Michael; Burke, Carol A

    2016-02-01

    This case illustrates a rare cause of gastro-intestinal bleeding following bariatric surgery. Though it is essential to rule out common causes of variceal formation accompanied by intermittent, profuse bleeding, there should be a high degree of suspicion of this rare etiology in patients who have previously undergone alteration of their anatomy, especially Roux-en-Y gastric bypass (RYGB). The case emphasizes the need for a multidisciplinary medical-surgical team in evaluating and treating patients who present with complex intra-abdominal pathology.

  18. Genome sequence of Victivallis vadensis ATCC BAA-548, an anaerobic bacterium from the phylum Lentisphaerae, isolated from the human gastro-intestinal tract

    SciTech Connect

    Van Passel, Mark W.J.; Kant, Ravi; Palva, Airi; Lucas, Susan; Copeland, A; Lapidus, Alla L.; Glavina Del Rio, Tijana; Dalin, Eileen; Tice, Hope; Bruce, David; Goodwin, Lynne A.; Pitluck, Sam; Davenport, Karen W.; Sims, David; Detter, J. Chris; Han, Cliff; Larimer, Frank W; Land, Miriam L; Hauser, Loren John; Kyrpides, Nikos C; Ovchinnikova, Galina; Richardson, Paul; De Vos, Willem M.; Smidt, Hauke; Zoetendal, Erwin G.

    2011-01-01

    Victivallis vadensis ATCC BAA-548 represents the first cultured representative from the novel phylum Lentisphaerae, a deep-branching bacterial lineage. Few cultured bacteria from this phylum are known, and V. vadensis therefore represents an important organism for evolutionary studies. V. vadensis is a strictly anaerobic sugar-fermenting isolate from the human gastro-intestinal tract.

  19. A hypothetical model of host-pathogen interaction of Streptococcus suis in the gastro-intestinal tract

    PubMed Central

    Ferrando, Maria Laura; Schultsz, Constance

    2016-01-01

    ABSTRACT Streptococcus suis (SS) is a zoonotic pathogen that can cause systemic infection in pigs and humans. The ingestion of contaminated pig meat is a well-established risk factor for zoonotic S. suis disease. In our studies, we provide experimental evidence that S. suis is capable to translocate across the host gastro-intestinal tract (GIT) using in vivo and in vitro models. Hence, S. suis should be considered an emerging foodborne pathogen. In this addendum, we give an overview of the complex interactions between S. suis and host-intestinal mucosa which depends on the host origin, the serotype and genotype of S. suis, as well as the presence and expression of virulence factors involved in host-pathogen interaction. Finally, we propose a hypothetical model of S. suis interaction with the host-GIT taking in account differences in conditions between the porcine and human host. PMID:26900998

  20. Haemosuccus pancreaticus, an uncommon cause of upper gastro intestinal bleeding: Case report and review of the literature.

    PubMed

    Shah, Amir Ali; Charon, Jean Pierre

    2015-06-01

    Haemosuccus Pancreaticus is defined as upper gastro intestinal (GI) bleeding from the ampula of vater via the pancreatic duct. It is most commonly associated with pancreatic inflammation, erosion of the pancrease by aneurysm or pseudo-aneurysm of the splenic artery. We report a 69 year old man with previous history of acute pancreatitis who was admitted with recurrent haematemesis. Initial upper GI endocopy was normal, while admitted, he collapse with abdominal pain and hypotension. He was resuscitated with blood and intravenous fluid. Repeat upper GI endocopy showed fresh blood in the duodenum, but no active bleeding site was demonstrated. An urgent coeliac axis CT angiogram was done which showed an splenic artery pseudo-aneurysm, which was successfully embolized. Patient is well 9 months after the procedure. This case highlights the importance of considering coeliac axis CT angiogram as part of investigation for obscure GI bleeding.

  1. Curiouser and Curiouser: The Macrocyclic Lactone, Abamectin, Is also a Potent Inhibitor of Pyrantel/Tribendimidine Nicotinic Acetylcholine Receptors of Gastro-Intestinal Worms.

    PubMed

    Abongwa, Melanie; Buxton, Samuel K; Robertson, Alan P; Martin, Richard J

    2016-01-01

    Nematode parasites may be controlled with drugs, but their regular application has given rise to concerns about the development of resistance. Drug combinations may be more effective than single drugs and delay the onset of resistance. A combination of the nicotinic antagonist, derquantel, and the macrocyclic lactone, abamectin, has been found to have synergistic anthelmintic effects against gastro-intestinal nematode parasites. We have observed in previous contraction and electrophysiological experiments that derquantel is a potent selective antagonist of nematode parasite muscle nicotinic receptors; and that abamectin is an inhibitor of the same nicotinic receptors. To explore these inhibitory effects further, we expressed muscle nicotinic receptors of the nodular worm, Oesophagostomum dentatum (Ode-UNC-29:Ode-UNC-63:Ode-UNC-38), in Xenopus oocytes under voltage-clamp and tested effects of abamectin on pyrantel and acetylcholine responses. The receptors were antagonized by 0.03 μM abamectin in a non-competitive manner (reduced Rmax, no change in EC50). This antagonism increased when abamectin was increased to 0.1 μM. However, when we increased the concentration of abamectin further to 0.3 μM, 1 μM or 10 μM, we found that the antagonism decreased and was less than with 0.1 μM abamectin. The bi-phasic effects of abamectin suggest that abamectin acts at two allosteric sites: one high affinity negative allosteric (NAM) site causing antagonism, and another lower affinity positive allosteric (PAM) site causing a reduction in antagonism. We also tested the effects of 0.1 μM derquantel alone and in combination with 0.3 μM abamectin. We found that derquantel on these receptors, like abamectin, acted as a non-competitive antagonist, and that the combination of derquantel and abamectin produced greater inhibition. These observations confirm the antagonistic effects of abamectin on nematode nicotinic receptors in addition to GluCl effects, and illustrate more complex

  2. Curiouser and Curiouser: The Macrocyclic Lactone, Abamectin, Is also a Potent Inhibitor of Pyrantel/Tribendimidine Nicotinic Acetylcholine Receptors of Gastro-Intestinal Worms

    PubMed Central

    Abongwa, Melanie; Buxton, Samuel K.; Robertson, Alan P.; Martin, Richard J.

    2016-01-01

    Nematode parasites may be controlled with drugs, but their regular application has given rise to concerns about the development of resistance. Drug combinations may be more effective than single drugs and delay the onset of resistance. A combination of the nicotinic antagonist, derquantel, and the macrocyclic lactone, abamectin, has been found to have synergistic anthelmintic effects against gastro-intestinal nematode parasites. We have observed in previous contraction and electrophysiological experiments that derquantel is a potent selective antagonist of nematode parasite muscle nicotinic receptors; and that abamectin is an inhibitor of the same nicotinic receptors. To explore these inhibitory effects further, we expressed muscle nicotinic receptors of the nodular worm, Oesophagostomum dentatum (Ode-UNC-29:Ode-UNC-63:Ode-UNC-38), in Xenopus oocytes under voltage-clamp and tested effects of abamectin on pyrantel and acetylcholine responses. The receptors were antagonized by 0.03 μM abamectin in a non-competitive manner (reduced Rmax, no change in EC50). This antagonism increased when abamectin was increased to 0.1 μM. However, when we increased the concentration of abamectin further to 0.3 μM, 1 μM or 10 μM, we found that the antagonism decreased and was less than with 0.1 μM abamectin. The bi-phasic effects of abamectin suggest that abamectin acts at two allosteric sites: one high affinity negative allosteric (NAM) site causing antagonism, and another lower affinity positive allosteric (PAM) site causing a reduction in antagonism. We also tested the effects of 0.1 μM derquantel alone and in combination with 0.3 μM abamectin. We found that derquantel on these receptors, like abamectin, acted as a non-competitive antagonist, and that the combination of derquantel and abamectin produced greater inhibition. These observations confirm the antagonistic effects of abamectin on nematode nicotinic receptors in addition to GluCl effects, and illustrate more complex

  3. Hospital Authority audit of the outcome of endoscopic resection of superficial upper gastro-intestinal lesions in Hong Kong.

    PubMed

    Teoh, Anthony Y B; Chiu, Philip W Y; Chan, S Y; Cheung, Frances K Y; Chu, K M; Kao, S S; Lai, T W; Lau, C W; Law, Simon Y K; Leung, Canice T L; Leung, W K; Tong, Daniel K H; Tsang, S H

    2015-06-01

    To review the short-term outcome of endoscopic resection of superficial upper gastro-intestinal lesions in Hong Kong. Historical cohort study. All Hospital Authority hospitals in Hong Kong. This was a multicentre retrospective study of all patients who underwent endoscopic resection of superficial upper gastro-intestinal lesions between January 2010 and June 2013 in all government-funded hospitals in Hong Kong. Indication of the procedures, peri-procedural and procedural parameters, oncological outcomes, morbidity, and mortality. During the study period, 187 lesions in 168 patients were resected. Endoscopic mucosal resection was performed in 34 (18.2%) lesions and endoscopic submucosal dissection in 153 (81.8%) lesions. The mean size of the lesions was 2.6 (standard deviation, 1.8) cm. The 30-day morbidity rate was 14.4%, and perforations and severe bleeding occurred in 4.3% and 3.2% of the patients, respectively. Among patients who had dysplasia or carcinoma, R0 resection was achieved in 78% and the piecemeal resection rate was 11.8%. Lateral margin involvement was 14% and vertical margin involvement was 8%. Local recurrence occurred in 9% of patients and 15% had residual disease. The 2-year overall survival rate and disease-specific survival rate was 90.6% and 100%, respectively. Endoscopic mucosal resection and endoscopic submucosal dissection were introduced in low-to-moderate-volume hospitals with acceptable morbidity rates. The short-term survival was excellent. However, other oncological outcomes were higher than those observed in high-volume centres and more secondary procedures were required.

  4. Ethanolic extracts of Inula viscosa, Salix alba and Quercus calliprinos, negatively affect the development of the entomopathogenic nematode, Heterorhabditis bacteriophora - A model to compare gastro-intestinal nematodes developmental effect.

    PubMed

    Santhi, Velayudhan Satheeja; Salame, Liora; Dvash, Levana; Muklada, Hussein; Azaizeh, Hassan; Mreny, Raghda; Awwad, Safaa; Markovics, Alex; Landau, Serge Yan; Glazer, Itamar

    2017-05-01

    Heterorhabditis bacteriophora can represent a model system for herbal medication against gastro-intestinal strongylid parasites in determining the recovery and development due to their unique parasitic infectious cycle. The fact that plant extracts impair nematode development is known but their differential impact on stages of the life cycle of H. bacteriophora has never been investigated. We examined the developmental stages resumed from eggs, young juveniles (J1-3), infective juveniles (IJs), young and adult hermaphrodites of H. bacteriophora upon exposure to crude ethanolic extracts of Inula viscosa, Salix alba, and Quercus calliprinos at concentrations of 600, 1200, and 2400ppm. Our results showed that plant extracts were highly toxic to the survival of the eggs and young juveniles J1 to J3 at all concentrations. The plant extracts inhibited their development and were associated with low reproduction parameters (i.e. fecundity and viability of eggs). The IJs, J4, young and developed hermaphrodites displayed concentration-dependent negative effect on development with less egg count, poor vulval muscle development, loss of egg laying capacity and progeny development by matricidal hatching. Plant extract of I. viscosa at low (600ppm) concentration did not impair vulval development. These results suggest that these plant extracts show potential for the control of parasitic rhabditids. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Prevalence of common gastrointestinal nematode parasites in scavenging pigs of different ages and sexes in eastern centre province, Burkina Faso.

    PubMed

    Tamboura, H H; Banga-Mboko, H; Maes, D; Youssao, I; Traore, A; Bayala, B; Dembele, M A

    2006-03-01

    The range and infestation intensities of gastrointestinal parasitic nematode species depend on the type of swine production system. The present study focused mainly on nematodes of veterinary importance in scavenging pigs in Burkina Faso, and aimed at determining the prevalence of gastro-intestinal nematode parasites by means of faecal egg per gram (EPG) counts. Between November 2001 and October 2002, faecal samples from 383 pigs of different sexes and ages (< 5 months, 5-12 months and > 12 months) were collected from the rectum and examined for gastrointestinal nematodes parasites using the Mc Master method. Of the 383 pigs examined, 91% were infected by one or more parasites. Ascaris suum (40%; 100-1 400 EPG) was the most prevalent parasite followed by Strongyloides ransomi (21%; 100-4200 EPG), Oesophagostomum spp. (18%; 100-1000 EPG), Hyostrongylus rubidus (11%; 100-1 800 EPG), Globocephalus spp. (10%; 100-400 EPG) and Trichuris suis (1 %; 100-200 EPG). The prevalence was significantly higher in female pigs (n = 239) than in males. In addition, females excreted significantly (P < 0.05) more eggs in their faeces than males, except in the case of Globocephalus spp. The age of the animal had no effect on the prevalence of A. suum whereas there were significant differences in age categories concerning S. ransomi, H. rubidus, Oesophagostumum spp. and Globocephalus spp. Unexpectedly, the high prevalence of these common parasites was not accompanied by elevated EPG values, which suggests the existence of moderate infestations. The present work indicates that the common nematode infestations in pigs do not necessarily need a systematic herd anthelmintic treatment, as only a small number of worms is required to induce immunity. A further study is needed to formulate appropriate and cost-effective strategies for the control of gastro-intestinal nematode parasites in pigs in Burkina Faso.

  6. Prevalence and distribution of gastro-intestinal helminths and haemoparasites in young scavenging chickens in upper eastern region of Ghana, West Africa.

    PubMed

    Poulsen, J; Permin, A; Hindsbo, O; Yelifari, L; Nansen, P; Bloch, P

    2000-06-12

    We conducted a cross-sectional study to determine the prevalence and species of gastro-intestinal helminths and haemoparasites in 100 chickens kept under extensive management systems in Ghana, West Africa. All the examined chickens (100%) were infected with gastro-intestinal helminths; a total of 18 species were detected. The species and their prevalences were: Acuaria hamulosa (25%), Allodapa suctoria (20%), Ascaridia galli (24%), Capillaria spp. (60%), Choanotaenia infundibulum (13%), Gongylonema ingluvicola (62%), Heterakis gallinarum (31%), H. isolonche (16%), Hymenolepis spp. (66%), Raillietina cesticillus (12%), R. echinobothrida (81%), R. tetragona (59%), Strongyloides avium (2%), Subulura strongylina (10%), Tetrameres fissispina (58%), Trichostronygylus tenuis (2%), and finally one unidentified acanthocephalan (1%) and one unidentified trematode (1%). Thirty-five per cent of the chickens were infected with the haemoparasites Aegyptinella pullorum and Plasmodium juxtanucleare (prevalences 9% and 27%, respectively). Association between chicken sex and prevalences was not significant. An over-dispersed distribution was seen for most of the helminth species.

  7. Heritable variation in resistance to gastro-intestinal nematodes in an unmanaged mammal population.

    PubMed

    Smith, J A; Wilson, K; Pilkington, J G; Pemberton, J M

    1999-06-22

    The impact of parasites on natural populations has received considerable attention from evolutionary biologists in recent years. Central to a number of theoretical developments during this period is the assumption of additive genetic variation in resistance to parasites. However, very few studies have estimated the heritability of parasite resistance under field conditions, and those that have are mainly restricted to birds and their ectoparasites. In this paper, to our knowledge, we show for the first time in a free-ranging mammal population, Soay sheep (Ovis aries) living on the islands of St Kilda, that there is significant heritable variation in resistance to gastrointestinal nematodes. This result is consistent with earlier studies on this population which have indicated locus-specific associations with parasite resistance. We discuss our results in the context of current studies examining heritable resistance to parasites in domestic sheep and the possible mechanisms of selective maintenance of genetic variation for resistance to gastrointestinal nematodes in the St Kilda Soay sheep population.

  8. Development and Validation of an in vitro Experimental GastroIntestinal Dialysis Model with Colon Phase to Study the Availability and Colonic Metabolisation of Polyphenolic Compounds.

    PubMed

    Breynaert, Annelies; Bosscher, Douwina; Kahnt, Ariane; Claeys, Magda; Cos, Paul; Pieters, Luc; Hermans, Nina

    2015-08-01

    The biological effects of polyphenols depend on their mechanism of action in the body. This is affected by bioconversion by colon microbiota and absorption of colonic metabolites. We developed and validated an in vitro continuous flow dialysis model with colon phase (GastroIntestinal dialysis model with colon phase) to study the gastrointestinal metabolism and absorption of phenolic food constituents. Chlorogenic acid was used as model compound. The physiological conditions during gastrointestinal digestion were mimicked. A continuous flow dialysis system simulated the one-way absorption by passive diffusion from lumen to mucosa. The colon phase was developed using pooled faecal suspensions. Several methodological aspects including implementation of an anaerobic environment, adapted Wilkins Chalgren broth medium, 1.10(8) CFU/mL bacteria suspension as inoculum, pH adaptation to 5.8 and implementation of the dialysis system were conducted. Validation of the GastroIntestinal dialysis model with colon phase system showed a good recovery and precision (CV < 16 %). Availability of chlorogenic acid in the small intestinal phase (37 ± 3 %) of the GastroIntestinal dialysis model with colon phase is comparable with in vivo studies on ileostomy patients. In the colon phase, the human faecal microbiota deconjugated chlorogenic acid to caffeic acid, 3,4-dihydroxyphenyl propionic acid, 4-hydroxybenzoic acid, 3- or 4-hydroxyphenyl acetic acid, 2-methoxy-4-methylphenol and 3-phenylpropionic acid. The GastroIntestinal dialysis model with colon phase is a new, reliable gastrointestinal simulation system. It permits a fast and easy way to predict the availability of complex secondary metabolites, and to detect metabolites in an early stage after digestion. Isolation and identification of these metabolites may be used as references for in vivo bioavailability experiments and for investigating their bioactivity in in vitro experiments.

  9. Ontogeny of the VIP system in the gastro-intestinal tract of the Axolotl, Ambystoma mexicanum: successive appearance of co-existing PACAP and NOS.

    PubMed

    Badawy, Gamal; Reinecke, Manfred

    2003-03-01

    Evidence for the presence and potential co-existence of vasoactive intestinal polypeptide (VIP), pituitary adenylate cyclase-activating polypeptide (PACAP) and nitric oxide synthase (NOS) in gastro-intestinal endocrine cells and/or nerve fibers is conflicting and very few results exist on development. This immunofluorescence study aims to clarify the appearance and localization of VIP, PACAP and NOS in the gastro-intestinal tract of the Axolotl, Ambystoma mexicanum, during ontogeny. VIP-immunoreactivity appeared in nerve fibers as early as on day 3 after hatching likely indicating a particular role, such as a trophic action, of VIP in very early development. PACAP-immunoreactivity was observed 3 days later within the VIP-immunoreactive (-IR) fibers. From this time on, VIP- and PACAP-immunoreactivity exhibited complete co-existence. VIP/PACAP-IR fibers were found throughout the gastro-intestinal tract. They were most prominent in the myenteric plexus and the muscle layers and less frequent in the submucosa. NOS-immunoreactivity appeared as late as at the 1st (64 days) juvenile stage in a subpopulation of the VIP/PACAP-IR fibers that contacted submucosal arteries. We found only very few VIP/PACAP-IR perikarya, indicating that part of the VIP/PACAP-IR fibers is of extrinsic origin. On day 12 and in the 1st and 2nd (104 days) juvenile stage, infrequent PACAP-IR entero-endocrine cells were noted, while neither VIP- nor NOS-immunoreactivity occurred in endocrine cells at any stage of development. The complete coexistence of neuronal PACAP- and VIP-immunoreactivities and their very early appearance in ontogeny may suggest important and coordinated roles of both peptides in the control of Axolotl gastro-intestinal activity, while the VIP/ PACAP/NOS-IR fibers may be involved in the regulation of submucosal blood flow.

  10. Selective exposure of the fetal lung and skin/amnion (but not gastro-intestinal tract) to LPS elicits acute systemic inflammation in fetal sheep.

    PubMed

    Kemp, Matthew W; Kannan, Paranthaman Senthamarai; Saito, Masatoshi; Newnham, John P; Cox, Tom; Jobe, Alan H; Kramer, Boris W; Kallapur, Suhas G

    2013-01-01

    Inflammation of the uterine environment (commonly as a result of microbial colonisation of the fetal membranes, amniotic fluid and fetus) is strongly associated with preterm labour and birth. Both preterm birth and fetal inflammation are independently associated with elevated risks of subsequent short- and long-term respiratory, gastro-intestinal and neurological complications. Despite numerous clinical and experimental studies to investigate localised and systemic fetal inflammation following exposure to microbial agonists, there is minimal data to describe which fetal organ(s) drive systemic fetal inflammation. We used lipopolysaccharide (LPS) from E.coli in an instrumented ovine model of fetal inflammation and conducted a series of experiments to assess the systemic pro-inflammatory capacity of the three major fetal surfaces exposed to inflammatory mediators in pregnancy (the lung, gastro-intestinal tract and skin/amnion). Exposure of the fetal lung and fetal skin/amnion (but not gastro-intestinal tract) caused a significant acute systemic inflammatory response characterised by altered leucocytosis, neutrophilia, elevated plasma MCP-1 levels and inflammation of the fetal liver and spleen. These novel findings reveal differential fetal organ responses to pro-inflammatory stimulation and shed light on the pathogenesis of fetal systemic inflammation after exposure to chorioamnionitis.

  11. Microencapsulation of a probiotic and prebiotic in alginate-chitosan capsules improves survival in simulated gastro-intestinal conditions.

    PubMed

    Chávarri, María; Marañón, Izaskun; Ares, Raquel; Ibáñez, Francisco C; Marzo, Florencio; Villarán, María del Carmen

    2010-08-15

    Chitosan was used as a coating material to improve encapsulation of a probiotic and prebiotic in calcium alginate beads. Chitosan-coated alginate microspheres were produced to encapsulate Lactobacillus gasseri (L) and Bifidobacterium bifidum (B) as probiotics and the prebiotic quercetin (Q) with the objective of enhancing survival of the probiotic bacteria and keeping intact the prebiotic during exposure to the adverse conditions of the gastro-intestinal tract. The encapsulation yield for viable cells for chitosan-coated alginate microspheres with quercetin (L+Q and B+Q) was very low. These results, together with the study about the survival of microspheres with quercetin during storage at 4 degrees C, demonstrated that probiotic bacteria microencapsulated with quercetin did not survive. Owing to this, quercetin and L. gasseri or B. bifidum were microencapsulated separately. Microencapsulated L. gasseri and microencapsulated B. bifidum were resistant to simulated gastric conditions (pH 2.0, 2h) and bile solution (3%, 2h), resulting in significantly (p<0.05) improved survival when compared with free bacteria. This work showed that the microencapsulation of L. gasseri and B. bifidum with alginate and a chitosan coating offers an effective means of delivery of viable bacterial cells to the colon and maintaining their survival during simulated gastric and intestinal juice.

  12. Pomegranate ellagitannins inhibit α-glucosidase activity in vitro and reduce starch digestibility under simulated gastro-intestinal conditions.

    PubMed

    Bellesia, Andrea; Verzelloni, Elena; Tagliazucchi, Davide

    2015-02-01

    Pomegranate extract was tested for its ability to inhibit α-amylase and α-glucosidase activity. Pomegranate extract strongly inhibited rat intestinal α-glucosidase in vitro whereas it was a weak inhibitor of porcine α-amylase. The inhibitory activity was recovered in an ellagitannins-enriched fraction and punicalagin, punicalin, and ellagic acid were identified as α-glucosidase inhibitors (IC(50) of 140.2, 191.4, and 380.9 μmol/L, respectively). Kinetic analysis suggested that the pomegranate extract and ellagitannins inhibited α-glucosidase activity in a mixed mode. The inhibitory activity was demonstrated using an in vitro digestion system, mimicking the physiological gastro-intestinal condition, and potatoes as food rich in starch. Pre-incubation between ellagitannins and α-glucosidase increased the inhibitory activity, suggesting that they acted by binding to α-glucosidase. During digestion punicalin and punicalagin concentration decreased. Despite this loss, the pomegranate extract retained high inhibitory activity. This study suggests that pomegranate ellagitannins may inhibit α-glucosidase activity in vitro possibly affecting in vivo starch digestion.

  13. Fish oil based vitamin D nanoencapsulation by ultrasonication and bioaccessibility analysis in simulated gastro-intestinal tract.

    PubMed

    Walia, Niharika; Dasgupta, Nandita; Ranjan, Shivendu; Chen, Lingyun; Ramalingam, Chidambaram

    2017-11-01

    Recently, nanoemulsions have been employed for different applications including food and drug industries for efficient nutrient delivery system. In this study, vitamin D (a lipophilic molecule) was encapsulated in fish oil for higher oral bioavailability. The oil-in-water nanoemulsion was formulated by ultrasonication technique with a droplet size range of 300-450nm and a shelf life of more than 90days. The influence of oil, water and surfactant concentration was investigated by phase diagram. The formulated nanoemulsion had encapsulation efficiency in the range of 95.7-98.2%. Further, nanoemulsion passed through simulated gastro-intestinal tract revealed an increased bioavailability than non-encapsulated vitamin. Thus, the formulation can be used as a drug delivery vehicle for various lipophilic compounds. Till date, no one have fabricated an efficient nano-vehicle for the delivery of vitamin D as well as analyzed the efficient delivery system in simulated GI-tract, this is first of its kind study in this regard. This can be scaled up further after analyzing the safety aspects. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Active actinidin retains function upon gastro-intestinal digestion and is more thermostable than the E-64-inhibited counterpart.

    PubMed

    Grozdanovic, Milica M; Ostojic, Sanja; Aleksic, Ivana; Andjelkovic, Uros; Petersen, Arnd; Gavrovic-Jankulovic, Marija

    2014-11-01

    Actinidin is a cysteine protease and major allergen from kiwi fruit. When purified under specific native conditions, actinidin preparations from fresh kiwi fruit contain both an active and inactive form of this enzyme. In this study, biochemical and immunological properties upon simulated gastro-intestinal digestion, as well as thermal stability, were investigated for both active and E-64-inhibited actinidin. Active actinidin retained its primary structure and proteolytic activity after 2 h of simulated gastric digestion, followed by 2 h of intestinal digestion, as assessed by SDS-PAGE, zymography and mass spectroscopy. Immunological reactivity of active actinidin was also preserved, as tested by immunoelectrophoresis. The E-64 inhibited actinidin was fully degraded after 1 h of pepsin treatment. Differential scanning calorimetry showed that active actinidin has one transition maximum temperature (Tm ) at 73.9°C, whereas in the E-64-actinidin complex the two actinidin domains unfolded independently, with the first domain having a Tm value of only 61°C. Active actinidin is capable of reaching the intestinal mucosa in a proteolytically active and immunogenic state. Inhibitor binding induces changes in the actinidin molecule that go beyond inhibition of proteolytic activity, also influencing the digestion stability and Tm values of actinidin, features important in the characterisation of food allergens. © 2014 Society of Chemical Industry.

  15. Effect of divalent minerals on the bioaccessibility of pure carotenoids and on physical properties of gastro-intestinal fluids.

    PubMed

    Corte-Real, Joana; Iddir, Mohammed; Soukoulis, Christos; Richling, Elke; Hoffmann, Lucien; Bohn, Torsten

    2016-04-15

    During digestion, high concentrations of divalent minerals (DMs) can lead to insoluble lipid-soap complex formation, hampering carotenoid bioaccessibility. The effect of varying concentrations (0-1000 mg/L) of calcium, magnesium, zinc and sodium (control) on the bioaccessibility of lutein, neoxanthin, lycopene and β-carotene, following in vitro gastro-intestinal digestion (GI), was investigated systematically and coupled with physical measurements of the digesta. Addition of DMs significantly decreased (p<0.001) carotenoid bioaccessibility, up to 100% in the case of calcium. Mean half maximal inhibitory concentrations (EC50) for calcium, magnesium and zinc were 270±18, 253±75 and 420±322 mg/L respectively. Increased DM concentrations correlated with decreased viscosity (r>0.9) and decreased carotenoid bioaccessibility. Surface tension of digesta correlated inversely (p<0.05) with the bioaccessibility of carotenoids. This correlation was mineral and carotenoid dependent. Although based on in vitro findings, it is plausible that similar interactions occur in vivo, with DMs affecting the bioaccessibility and bioavailability of carotenoids and other lipophilic micronutrients and phytochemicals. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Estimation of genetic parameters for resistance to gastro-intestinal nematodes in pure blood Arabian horses.

    PubMed

    Kornaś, Sławomir; Sallé, Guillaume; Skalska, Marta; David, Ingrid; Ricard, Anne; Cabaret, Jacques

    2015-03-01

    Equine internal parasites, mostly cyathostomins, affect both horse welfare and performance. The appearance of anthelmintic-resistant parasites creates a pressing need for optimising drenching schemes. This optimization may be achieved by identifying genetic markers associated with host susceptibility to infection and then to drench carriers of these markers. The aim of our study was to characterise the genetics of horse resistance to strongyle infection by estimating heritability of this trait in an Arabian pure blood population. A population of 789 Arabian pure blood horses from the Michałów stud farm, Poland were measured for strongyle egg excretion twice a year, over 8 years. Low repeatability values were found for faecal egg counts. Our analyses showed that less than 10% of the observed variation for strongyle faecal egg counts in this population had a genetic origin. However, additional analyses highlighted an age-dependent increase in heritability which was 0.04 (±0.02) in young horses (up to 3 years of age) but 0.21 (±0.04) in older ones. These results suggest that a significant part of the inter-individual variation has a genetic origin. This paves the way to a genomic dissection of horse-nematode interactions which might provide predictive markers of susceptibility, allowing individualised drenching schemes. Copyright © 2015 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

  17. A novel method of rejection of brood parasitic eggs reduces parasitism intensity in a cowbird host

    PubMed Central

    De Mársico, María C.; Gloag, Ros; Ursino, Cynthia A.; Reboreda, Juan C.

    2013-01-01

    The hosts of brood parasitic birds are under strong selection pressure to recognize and remove foreign eggs from their nests, but parasite eggs may be too large to be grasped whole and too strong to be readily pierced by the host's bill. Such operating constraints on egg removal are proposed to force some hosts to accept parasite eggs, as the costs of deserting parasitized clutches can outweigh the cost of rearing parasites. By fitting microcameras inside nests, we reveal that the Neotropical baywing (Agelaioides badius), a host of the screaming cowbird (Molothrus rufoaxillaris) and shiny cowbird (Molothrus bonariensis), instead circumvents such constraints by kicking parasite eggs out of the nest. To our knowledge, this is the first report of a passerine bird using its feet to remove objects from the nest. Kick-ejection was an all-or-nothing response. Baywings kick-ejected parasite eggs laid before their own first egg and, if heavily parasitized, they ejected entire clutches and began again in the same nest. Few baywings were able to rid their nests of every parasite egg, but their novel ejection method allowed them to reduce the median parasitism intensity by 75 per cent (from four to one cowbird eggs per nest), providing an effective anti-parasite defence. PMID:23485877

  18. Acute gastro-intestinal illness and its association with hydroclimatic factors in British Columbia, Canada: A time-series analysis

    NASA Astrophysics Data System (ADS)

    Galway, L. P.; Allen, D. M.

    2013-12-01

    Rising global temperatures and expected shifts in regional hydroclimatology in a changing climate are likely to influence the risk of infectious waterborne illness. This study examines the role of hydroclimatology as an underlying driver of the epidemiology of waterborne gastro-intestinal illness and contributes to our currently limited understanding of the possible ecosystem-mediated impacts of climate change on health. Using time-series regression analysis, we examine the associations between three hydroclimatic factors (monthly temperature, precipitation, and streamflow) and the monthly occurrence of AGI illness in two communities in the province of British Columbia, Canada. The two communities were selected as study sites to represent the dominant hydroclimatic regimes that characterize the province of BC: the rainfall-dominated hydroclimatic regime and snowmelt-dominated hydroclimatic regime Our results show that the number of monthly cases of AGI increased with increasing temperature, precipitation, and streamflow in the same month in the context of a rainfall-dominated regime and with increasing streamflow in the previous month in the context of a snowfall-dominated regime. These results suggest that hydroclimatic factors play a role in driving the occurrence and variability of AGI illness in this setting. Further, this study has highlighted that the nature and magnitude of the effects of hydroclimatic factors on waterborne illness vary across different hydroclimatic settings. We conclude that the watershed may be an appropriate context within which we can and should enhance our understanding of water-related climate change impacts on health. Examining the role of hydroclimatology as an underlying driver of the epidemiology of infectious disease is key to understanding of the possible ecosystem-mediated impacts of climate change on health and developing appropriate adaptation responses.

  19. Gastro-intestinal transport of calcium and cadmium in fresh water and seawater acclimated trout (Oncorhynchus mykiss).

    PubMed

    Klinck, Joel S; Wood, Chris M

    2013-03-01

    Transport of calcium (Ca) and cadmium (Cd) was examined along the gastro-intestinal tract (GIT) of freshwater and seawater Oncorhynchus mykiss irideus (FWT and SWTies respectively) using in vitro and in vivo experiments. Based on known physiological differences between FWT and SWT which aid in regulating ion levels and osmolarity, we hypothesized that SWT would have lower rates of Ca uptake. Also, we predicted that Cd rates would also be lower because Cd is known to share a common transport mechanism with Ca. Kinetics of Ca and Cd transport were determined using mucosal salines of varying concentrations [1, 10, 30, 60, and 100 (mmolL(-1) for Ca, μmolL(-1) for Cd)]. Linear and saturating relationships were found for Ca for FWT and SWT, but overall SWT had lower rates. Linear and/or saturating relationships were also found for Cd uptake, but rates varied little between fish types. Elevated Ca had no inhibitory effect on Cd transport, and Ca channel blockers nifedipine and verapamil had little effect on Ca or Cd uptake. However, lanthanum reduced Ca transport into some compartments. A 21 day in vivo feeding experiment was also performed where FWT and SWT were exposed to control diets or Cd-spiked diets (552 μg Cd g(-1) food). Whole body Cd uptake between fish types was similar, but the majority of Cd in SWT remained in the posterior intestine tissue, while FWT transported more Cd through their gut wall. Overall it appears that large differences in Ca and Cd uptake between FWT and SWT exist, with SWT generally having lower rates.

  20. Measurement of phenotypic resilience to gastro-intestinal nematodes in Merino sheep and association with resistance and production variables.

    PubMed

    Kelly, Gareth A; Kahn, Lewis P; Walkden-Brown, Stephen W

    2013-03-31

    A cross-over experiment was conducted to compare six different phenotypic measures of resilience to gastro-intestinal nematodes (predominantly Haemonchus contortus) in Merino sheep and their association with resistance and production levels. On each of six farms, 120 ewes born in 2006 and 120 older mixed age ewes were selected at shearing in 2007. Of these, 60 in each mob were serially treated with long-acting anthelmintics to suppress worm populations. The other 60 ewes were managed according to management practices employed on the farm (infected, INF). At shearing in 2008, the experimental sheep had their anthelmintic treatments switched. The experiment concluded at shearing in 2009. Measures of resilience were greasy fleece weight (GFW), live weight gain (LWG) and haematocrit (HCT) when infected and the difference in these variables between infected and suppressed. Resistance was determined from multiple faecal worm egg counts (WEC) when infected. Measures of resilience based on GFW, LWG and HCT were moderately correlated with each other (r=0.25-0.50) suggesting that they represent different traits. Correlations between a measure in infected animals, and the difference in the same measurement between infected and uninfected animals were higher (r=-0.37 to -0.82), indicating that measurement during infection is an adequate measure of resilience. WEC was negatively correlated with LWG and HCT during infection but not GFW. Correlations with resilience measures based on difference between infected and uninfected were positive. Surviving infected sheep were found to have higher haematocrit (HCT), and lower WEC in summer and autumn than sheep that died following the measurement. These results show that measurement of performance traits while infected is a reasonable approximation of measurement of resilience based on the difference in performance between infected and non-infected. They also show that resilience to worm infection is not a single trait, but rather a

  1. Identification of Rothia Bacteria as Gluten-Degrading Natural Colonizers of the Upper Gastro-Intestinal Tract

    PubMed Central

    Zamakhchari, Maram; Wei, Guoxian; Dewhirst, Floyd; Lee, Jaeseop; Schuppan, Detlef; Oppenheim, Frank G.; Helmerhorst, Eva J.

    2011-01-01

    Background Gluten proteins, prominent constituents of barley, wheat and rye, cause celiac disease in genetically predisposed subjects. Gluten is notoriously difficult to digest by mammalian proteolytic enzymes and the protease-resistant domains contain multiple immunogenic epitopes. The aim of this study was to identify novel sources of gluten-digesting microbial enzymes from the upper gastro-intestinal tract with the potential to neutralize gluten epitopes. Methodology/Principal Findings Oral microorganisms with gluten-degrading capacity were obtained by a selective plating strategy using gluten agar. Microbial speciations were carried out by 16S rDNA gene sequencing. Enzyme activities were assessed using gliadin-derived enzymatic substrates, gliadins in solution, gliadin zymography, and 33-mer α-gliadin and 26-mer γ-gliadin immunogenic peptides. Fragments of the gliadin peptides were separated by RP-HPLC and structurally characterized by mass spectrometry. Strains with high activity towards gluten were typed as Rothia mucilaginosa and Rothia aeria. Gliadins (250 µg/ml) added to Rothia cell suspensions (OD620 1.2) were degraded by 50% after ∼30 min of incubation. Importantly, the 33-mer and 26-mer immunogenic peptides were also cleaved, primarily C-terminal to Xaa-Pro-Gln (XPQ) and Xaa-Pro-Tyr (XPY). The major gliadin-degrading enzymes produced by the Rothia strains were ∼70–75 kDa in size, and the enzyme expressed by Rothia aeria was active over a wide pH range (pH 3–10). Conclusion/Significance While the human digestive enzyme system lacks the capacity to cleave immunogenic gluten, such activities are naturally present in the oral microbial enzyme repertoire. The identified bacteria may be exploited for physiologic degradation of harmful gluten peptides. PMID:21957450

  2. N-nitrosation of medicinal drugs catalysed by bacteria from human saliva and gastro-intestinal tract, including Helicobacter pylori.

    PubMed

    Ziebarth, D; Spiegelhalder, B; Bartsch, H

    1997-02-01

    Micro-organisms commonly present in human saliva and three DSM strains (Helicobacter pylori, Campylobacter jejuni and Neisseria cinerea), which can be isolated from the human gastro-intestinal tract, were assayed in vitro for their capacity to catalyse N-nitrosation of a series of medicinal drugs and other compounds. Following incubation at pH 7.2 in the presence of nitrate (or nitrite) for up to 24 (48) h, the yield of N-nitroso compounds (NOC) was quantified by HPLC equipped with a post-column derivatization device, allowing the sensitive detection of acid-labile and acid-stable NOC. Eleven out of the 23 test compounds underwent bacteria-catalysed nitrosation by salivary bacteria, the yield of the respective nitrosation products varying 800-fold. 4-(Methylamino)antipyrine exhibited the highest rate of nitrosation, followed by dichlofenac > metamizole > piperazine > five other drugs, whilst L-proline and L-thioproline had the lowest nitrosation rate. Ten drugs including aminophenazone, cimetidine and nicotine, did not inhibit bacterial growth, allowing transitory nitrite to be formed, but no N-nitroso derivatives were detected. Three drugs inhibited the proliferation of bacteria and neither nitrite nor any NOC were formed. Using metamizole as an easily nitrosatable precursor, two strains, Campylobacter jejuni and Helicobacter pylori, were shown to catalyse nitrosation in the presence of nitrite at pH 7.2. As compared to Neisseria cinerea used as a nitrosation-proficient control strain, H. pylori was 30-100 times less effective, whilst C. jejuni had intermediary activity. The results of our sensitive nitrosation assay further confirm that bacteria isolated from human sources, possessing nitrate reductase and/or nitrosating enzymes such as cytochrome cd1-nitrite reductase (Calmels et al., Carcinogenesis, 17, 533-536, 1996), can contribute to intragastric nitrosamine formation in the anacidic stomach when nitrosatable precursors from exogenous and endogenous sources

  3. Seasonal variations in the gastro-intestinal nematode populations of Scottish hil sheep.

    PubMed

    Reid, J F; Armour, J

    1975-05-01

    In each of two consecutive years, groups of breeding ewes were removed from a hill farm in the west of Scotland on four occasions, namely late pregnancy, early lactation, autumn and early winter. At slaughter the major nematode genus present in the alimentary tract was Ostertagia, with O circumcincta the predominant species but three species previously found in Scottish hill sheep, Bunostomum trigonocephalum, Strongyloides papillosis and Chabertia ovina were absent. An absolute increase in total nematode burden and faecal egg count was apparent in the ewes commencing in late pregnancy, reaching a maximum during lactation and falling again in autumn and early winter. This peri-parturient increase in the nematode population could not be solely attributed to the maturation of previously inhibited larval stages but was primarily the result of the development of recently ingested infection; the latter situation thought to be due to a temporary relaxation of immunological response by the ewe at parturition or early lactation. Serum pepsinogen values in ewes remained elevated throughout the grazing season and were always higher than those of their lambs, suggesting that the ewe, although allowing few parasites to become established, was under considerable challenge in the autumn. The worm burdens of the lambs were always low in autumn and early winter with Ostertagia spp being the major genus present during the autumn and Trichostrongylus spp being the predominant genus during the early winter.

  4. In vitro antioxidant and anti-inflammatory activities of Radix Isatidis extract and bioaccessibility of six bioactive compounds after simulated gastro-intestinal digestion.

    PubMed

    Xiao, Ping; Huang, Hongzhi; Chen, Jianwei; Li, Xiang

    2014-11-18

    Radix Isatidis called "Ban-Lan-Gen" is one of the most commonly-used traditional Chinese medicines for antiviral, anti-inflammatory, antioxidant and antipyretic purposes. Investigate the bioaccessibility of uridine, epigoitrin, adenosine, clemastanin B, indigoticoside A and isolariciresinol as well as the antioxidant and anti-inflammatory activities during an in vitro gastro-intestinal digestion of the Radix Isatidis extract (RIE). High performance liquid chromatography (HPLC) technique was adopted to determine the bioaccessibility of six bioactive compounds in RIE. Antioxidant activities of RIE in different digestive stages were determined by 1,1-Diphenyl-2-picrylhydrazyl (DPPH), superoxide anion and hydroxyl radical scavenging abilities. Anti-inflammatory activity was assayed by the inhibitions of inflammatory cytokines such as nitrous oxide (NO), prostaglandin E2 (PGE2) and tumor necrosis factor α(TNF-α) producted by lipopolysaccharide (LPS) stimulated RAW264.7 cells. The bioaccessibility of uridine, epigoitrin, adenosine, clemastanin B, indigoticoside A and isolariciresinol were 15.38%, 18.28%, 24.01%, 6.50%, 8.65% and 17.78%, respectively. Also, the digestion products still possessed certain antioxidant activities. The antioxidant activity was highly correlated with lignans (clemastanin B, indigoticoside A and isolariciresino). The anti-inflammation activity of the three samples decreased in the order: IN sample (the solution that had diffused into the dialysis tubing)>Nondigested sample (RIE solution)>Gastric sample (post-gastric digestion)>OUT sample (material that remained in the gastro-intestinal tract). Results obtained in this research reveal the amount of bioactive compounds from RIE that could be available for absorption in vivo. The antioxidant activity decreased significantly but the anti-inflammatory activity was enhanced in serum-available fraction after gastro-intestinal digestion in vitro. This study could provide a scientific basis for a

  5. [Systemic immunological response in children with chronic gingivitis and gastro-intestinal pathology].

    PubMed

    Romanenko, E G

    2014-01-01

    Study of the immune system mechanisms in chronic catarrhal gingivitis in children with gastrointestinal pathology was performed in 102 children (49 with chronic gastritis and duodenitis and 53 with no signs of gastrointestinal pathology). Forty-eight children with healthy periodontium constituted control group. Generalized chronic catarrhal gingivitis in children with gastroduodenal pathology is characterized by intense humoral response by simultaneous T-cell immunity suppression. Detection of high serum titers of circulating immune complexes in patients with chronic catarrhal gingivitis suggests a role of immune response in the pathogenesis of periodontal disease increases with concomitant diseases of the upper gastrointestinal tract.

  6. Prevalence and intensity of nematode parasites in Wisconsin ermine.

    PubMed

    Dubay, Shelli; Buchholz, Matthew J; Lisiecki, Robert; Huspeni, Todd; Ginnett, Tim; Haen, Luke; Borsdorf, Phil

    2014-10-01

    In the midwestern United States, ermine ( Mustela erminea ) are economically important because they are legally harvested for pelts. Information on parasites of ermine is lacking, and the effects that nematode parasites have on body condition of ermine hosts are unknown. We identified Skrjabingylus nasicola and Filaroides martis in ermine trapped from 2007 to 2013 from 6 counties in Wisconsin. Small mammals, commonly consumed by ermine, serve as paratenic hosts for both parasites. Our goal was to identify how age and sex of ermine, along with year, influence nematode parasitism. We also investigated how infection affected body condition for male and female ermine using body mass standardized by length as an index of body condition. We commonly found S. nasicola and F. martis in male and female ermine, but both prevalence and intensity of infection were higher for males. Relative to juveniles (<1 yr), adult (>1 yr) male ermine did not exhibit significantly higher intensity or prevalence of either parasite. We found that body condition was not compromised by infection for either sex, and intensity of S. nasicola and prevalence of F. martis were highest during the 2010-2011 trapping season. Of the 6 yr studied, precipitation was highest during the summer before the 2010-2011 season, and increased precipitation can cause increases in populations of gastropod intermediate hosts. We think that several distinct natural history components, namely, mating structure, diet, and metabolic rate, influence nematode parasitism in ermine.

  7. Fluorescence multi-scale endoscopy and its applications in the study and diagnosis of gastro-intestinal diseases: set-up design and software implementation

    NASA Astrophysics Data System (ADS)

    Gómez-García, Pablo Aurelio; Arranz, Alicia; Fresno, Manuel; Desco, Manuel; Mahmood, Umar; Vaquero, Juan José; Ripoll, Jorge

    2015-06-01

    Endoscopy is frequently used in the diagnosis of several gastro-intestinal pathologies as Crohn disease, ulcerative colitis or colorectal cancer. It has great potential as a non-invasive screening technique capable of detecting suspicious alterations in the intestinal mucosa, such as inflammatory processes. However, these early lesions usually cannot be detected with conventional endoscopes, due to lack of cellular detail and the absence of specific markers. Due to this lack of specificity, the development of new endoscopy technologies, which are able to show microscopic changes in the mucosa structure, are necessary. We here present a confocal endomicroscope, which in combination with a wide field fluorescence endoscope offers fast and specific macroscopic information through the use of activatable probes and a detailed analysis at cellular level of the possible altered tissue areas. This multi-modal and multi-scale imaging module, compatible with commercial endoscopes, combines near-infrared fluorescence (NIRF) measurements (enabling specific imaging of markers of disease and prognosis) and confocal endomicroscopy making use of a fiber bundle, providing a cellular level resolution. The system will be used in animal models exhibiting gastro-intestinal diseases in order to analyze the use of potential diagnostic markers in colorectal cancer. In this work, we present in detail the set-up design and the software implementation in order to obtain simultaneous RGB/NIRF measurements and short confocal scanning times.

  8. Intensity of parasitic infestation in silver carp, Hypophthalmichthys molitrix *

    PubMed Central

    Alam, M. M.; Khan, M. A.; Hussain, M. A.; Moumita, D.; Mazlan, A. G.; Simon, K. D.

    2012-01-01

    Silver carp, Hypopthalmichthys molitrix is one of the most economically valuable fish species in Bangladesh. However, its production is often hindered by parasite-induced mortality. The present study reports the intensity of parasitic infestation in 216 specimens of H. molitrix collected from different fish markets in Rajshahi City, Bangladesh. Nine different parasite species (Trichodina pediculatus, Dactylogyrus vastator, Ichthyophthirius multifilis, Gyrodactylus elegans, Lernaea sp., Apiosoma sp., Myxobolus rohitae, Camallanus ophiocephali, and Pallisentis ophiocephali) were recovered from the gill, skin, stomach, and intestine of host fish. The highest level of infection was observed for host skin, while lower levels were observed for host gill, stomach, and intestine. The results also revealed that the intensity of parasite infection in different organs of H. molitrix varied with the season. In particular, the highest levels of infection were recorded during the winter period (November–February), when fish are most susceptible to parasites. The findings of the study will help in the management and conservation of H. molitrix. PMID:23225858

  9. Intensity of parasitic infestation in silver carp, Hypophthalmichthys molitrix.

    PubMed

    Alam, M M; Khan, M A; Hussain, M A; Moumita, D; Mazlan, A G; Simon, K D

    2012-12-01

    Silver carp, Hypopthalmichthys molitrix is one of the most economically valuable fish species in Bangladesh. However, its production is often hindered by parasite-induced mortality. The present study reports the intensity of parasitic infestation in 216 specimens of H. molitrix collected from different fish markets in Rajshahi City, Bangladesh. Nine different parasite species (Trichodina pediculatus, Dactylogyrus vastator, Ichthyophthirius multifilis, Gyrodactylus elegans, Lernaea sp., Apiosoma sp., Myxobolus rohitae, Camallanus ophiocephali, and Pallisentis ophiocephali) were recovered from the gill, skin, stomach, and intestine of host fish. The highest level of infection was observed for host skin, while lower levels were observed for host gill, stomach, and intestine. The results also revealed that the intensity of parasite infection in different organs of H. molitrix varied with the season. In particular, the highest levels of infection were recorded during the winter period (November-February), when fish are most susceptible to parasites. The findings of the study will help in the management and conservation of H. molitrix.

  10. Performance and gastro-intestinal response of broiler chickens fed on cereal grain-based foods soaked in water.

    PubMed

    Yasar, S; Forbes, J M

    1999-03-01

    1. Two experiments were carried out to investigate the addition of 1 3 kg water per kg air-dry mash diets containing high proportions (600 to 700 g/kg) of ground cereal grains (wheat, barley or oats) on broiler performance and the structure and function of the gastro-intestinal tract. 2. Chicks at the age of 7 d were fed on the wheat-, barley- or oats-based diets in the dry or wet forms for 35 d. Food and water intakes were recorded daily while body weight was measured weekly. Two birds from each treatment were killed each week to measure gut size and the viscosity of gut contents. Tissue samples from various digestive segments were histo-morphologically examined to determine the thickness of tissue layers, size of tissue glands, villa heights, crypt depths and thickness of tunica muscularis. Crypt cell proliferation rate (CCPR) for each segment was also determined using a metaphase arrest technique. 3. The results from both experiments showed that wetting food significantly (P<0.05) increased food intake, total water intake and body weight gain of broiler chickens. The body weight gains of birds were proportional to their food intakes so that the efficiency of food utilisation was similar for all treatments. Dry matter retention of food tended to increase in birds given wet food from 7 to 21 d but not thereafter, compared to the dry-fed birds. Although water intake from the water bottle was significantly (P<0.05) reduced in birds given wet food, total water intakes from the water bottle plus that from food were significantly (P<0.05) higher in the wet-fed birds than in the dry-fed birds. The ratio of total water to dry food intake was, however, similar in both feeding regimens. 4. The fresh empty weight of the gut was increased by wet-feeding while its relative weight to body weight and the length of gut was not affected by dietary treatments. Significantly greater development of the tissue glands in the proventriculus and gizzard was observed in the birds given

  11. Effects of inhibition of prostaglandin endoperoxide synthase-2 in chronic gastro-intestinal ulcer models in rats

    PubMed Central

    Schmassmann, Adrian; Peskar, Brigitta M; Stettler, Christian; Netzer, Peter; Stroff, Thomas; Flogerzi, Beatrice; Halter, Fred

    1998-01-01

    In the stomach, prostaglandins protect the gastric mucosa against injuries. One rate-limiting step in prostaglandin synthesis is mediated by prostaglandin endoperoxide synthase (PGHS), the target enzyme of non-steroidal anti-inflammatory drugs (NSAIDs). Two isoforms of PGHS exist: a constitutive (PGHS-1) and an inducible (PGHS-2) enzyme. PGHS-1 is the major source of gastric prostaglandins under physiological conditions. Inhibition of prostaglandin synthesis by traditional NSAIDs such as indomethacin and diclofenac which non-selectively inhibit both PGHS-1 and PGHS-2, causes gastric and intestinal ulceration and delays gastric ulcer healing in chronic models. It has been shown that selective PGHS-2 inhibitors such as L-745,337 (5-methanesulphonamide-6-(2,4-difluorothio-phenyl)-1-indanone) are not ulcerogenic and do not inhibit gastro-intestinal prostaglandin synthesis. However, minimal information is available on the long-term effects of PGHS-2 inhibitors on the healing of previously established gastric injuries. We assessed the cellular localization and expression of PGHS-1 and PGHS-2 during gastric ulcer healing and assessed the effects of L-745,337 on previously established cryoulcers in the rat gastric stomach.PGHS-1 and PGHS-2 were located and quantified by immunohistochemistry during experimental gastric ulcer healing. PGHS-2 immunoreactivity was only negligible in the normal gastric wall, but after gastric ulcerations, it was strongly detected in monocytes, macrophages, fibroblasts and endothelial cells below and between the regenerative glands. PGHS-1 immunoreactivity detected in normal gastric mucosa, disappeared after gastric ulceration in the mucosa adjacent to the ulcer crater. However, it reappeared in the regenerative glands from day 5 onwards. Thus, PGHS-1 and PGHS-2 were located at different sites and their maximal expression followed a different time-sequence.We assessed the effects of L-745,337, indomethacin and diclofenac on gastric ulcer healing

  12. Effect of ageing on the gastro-intestinal transit of a lactulose-supplemented mixed solid-liquid meal in humans.

    PubMed

    Wegener, M; Börsch, G; Schaffstein, J; Lüth, I; Rickels, R; Ricken, D

    1988-01-01

    Gastro-intestinal transit of a mixed solid-liquid meal containing wheat bread, scrambled eggs, coffee labelled with 99mTc, orange juice with lactulose and indigocarmine was evaluated in 21 young control (mean age 33.5 years) and 25 elderly subjects (mean age 81.7 years) without gastrointestinal complaints or severe medical illness. The rate of gastric emptying was determined by an anterior gamma camera technique, mouth-to-caecum transit by the hydrogen breath test and whole-gut transit by the first stool passage of indigocarmine. Gastric emptying was significantly prolonged in older subjects: t1/2 = 136 +/- (SEM) 13 versus 81 +/- 4 min; p less than 0.001. Concerning mouth-to-caecum or whole-gut transit time, significant differences between the two study groups were not detected.

  13. Somatostatin receptor imaging with (111)In-pentetreotide in gastro-intestinal tract and lung neuroendocrine tumors-Impact on targeted treatment.

    PubMed

    Gerasimou, George; Moralidis, Efstratios; Gotzamani-Psarrakou, Anna

    2010-01-01

    Somatostatin is a neuropeptide that confers a wide range of pharmacological properties. Indium-111-tagged pentetreotide ((111)In-P) is a radiolabeled analogue of somatostatin indicated for the in vivo scintigraphic localization of neuroendocrine tumors (NET). In cases of NET of the gastro-intestinal tract we describe the sensitivity compared to conventional anatomical imaging modalities and especially the possibility that (111)In-P may change therapeutic management into up one fourth of the patients. In cases of small cell lung carcinoma it has been used for the evaluation of somatostatin receptor status and a substantial tool for differentiation between limited and extensive disease, especially when combined with anatomical imaging methods. We also describe the radiolabeled with yttrium-90 or lutetium-177 somatostatin analogue peptides in the treatment of NET and also the use of (111)In-P for the selection of patients for targeted treatment.

  14. Endohelminth parasites from salmonids in intensive culture from southern Chile.

    PubMed

    Torres, P; Quintanilla, J C; Rozas, M; Miranda, P; Ibarra, R; San Martín, M F; Raddatz, B; Wolter, M; Villegas, A; Canobra, C; Hausdorf, M; Silva, R

    2010-06-01

    A total of 228 salmonids (90 Oncorhynchus mykiss, 48 Oncorhynchus kisutch, and 90 Salmo salar) from 8 intensive aquaculture centers in the south of Chile were examined for endohelminths parasites between December 2008 and May 2009. The body cavities of 2 O. mykiss were infected by Diphyllobothrium sp. plerocercoids (prevalence: 6.7%, mean intensity: 1.0, mean abundance: 0.07) from the Lake Tarahuin hatchery on the south of Chiloé Island. Also, tetraphyllidean plerocercoids (prevalence: 3.3%, mean intensity: 1, mean abundance: 0.03) and fourth-stage larvae of Hysterothylacium aduncum (prevalence: 6.7%, mean intensity: 1, mean abundance 0.07) were observed in O. kisutch from a marine hatchery in Chiloé. The occurrences of Diphyllobothrium sp. in a lake and a tetraphyllidean plerocercoid from marine cultured salmonid in Chiloé are reported for first time. No muscular infection by helminths was recorded in the fish examined.

  15. Gastro-intestinal nematode infection in lambs — A model based on climatic indices for forecasting peak pasture larval contamination

    NASA Astrophysics Data System (ADS)

    Paton, G.

    1987-06-01

    The parasite Ostertagia circumcincta is the primary cause of parasitic gastro-enteritis in lambs during their first season at grass. The life-cycle of this nematode parasite involves the development and survival of the free-living stages on pasture. Accordingly the pasture is the site of deposition, development and transmission of infection and meteorological factors affecting the pasture will affect the parasites. In this paper two empirical models for forecasting the timing of the “summer wave” of infective larvae on pasture are presented. These models are similar in form to that described by Starr and Thomas (1980) but involve different approaches to assessing the temperature and moisture components of the daily index value. Further, using the prediction model described by Paton, Thomas and Waller (1984) as an investigative tool, certain tentative suggestions are made as to a general fundamental weakness of empirical index methods.

  16. Ethno-veterinary control of parasites, management and role of village chickens in rural households of Centane district in the Eastern Cape, South Africa.

    PubMed

    Mwale, M; Masika, P J

    2009-12-01

    Mwale and Masika 2009 Ethno-veterinary control of parasites, management and role of village chickens in rural households of Centane district in the Eastern Cape, South Africa. Tropical Animal Health and Production. Village chickens contribute significantly towards rural livelihood in the African continent through the provision of animal protein, income and socio-cultural uses. However, village chickens are susceptible to parasite infestation. Due to limitations of using western drugs to control these parasites, farmers resort to the use of ethno-veterinary medicine (EVM). However, there is dearth of information on EVM use in chickens. Therefore, the objective of the current study was to document various EVM practices used in controlling gastro-intestinal parasites in village chickens. Stratified random sampling was used to select 62 chicken farmers that were interviewed using a structured questionnaire About 70 and 96.7% of farmers provided housing and water for their chickens respectively whereas the rest did not. The chief role of chickens was meat provision (91.7%). Most households (86%) reported parasite problems in chickens, particularly gastro-intestinal parasites. Eighty-three percent of the interviewed respondents use medicinal plants to control both internal and external parasites in chickens. Use of plants increased with parasite incidences (r=0.347; P<0.01). Mainly gastro-intestinal parasites were problematic and were largely controlled by medicinal plants. Further research on pharmacological properties, safety and efficacy of these plants is important for improved chicken productivity and hence rural livelihood.

  17. Study of gastro-intestinal helminths of scavenging chickens in four rural districts of Amhara region, Ethiopia.

    PubMed

    Eshetu, Y; Mulualem, E; Ibrahim, H; Berhanu, A; Aberra, K

    2001-12-01

    A total of 267 rural scavenging chickens were examined from October 1998 to August 1999 in four woredas (districts) of the Amhara Region, Ethiopia. Of these chickens, 243 (91.01%) were found to harbour one to nine different helminth parasites and 24 (8.99%) were free of helminth parasites. A significant difference (P < 0.01) was found between the prevalence rates of helminth parasites in the different agro-ecological zones; the highest prevalence was observed in the lowland areas. This suggests that agro-ecology has a major influence on the distribution of helminth parasites. Nematodes recovered included Heterakis gallinarum (17.28%), Subulura brumpti (17.60%), Ascaridia galli (35.58%), Cheilospirura hamulosa (0.75%) and Dyspharynx spiralis (2.62%). The principal cestode species encountered were Raillietina echinobothrida (25.84%), Raillietina tetragona (45.69%), Raillietina cesticillus (5.62%), Amoebotaenia sphenoides (40.45%), Davainea proglottina (1.12%) and Choanotaenia infundibulum (4.49%).

  18. The effect of rotational grazing for periods of one or two weeks on the build-up of lungworm and gastro-intestinal nematode infections in calves.

    PubMed

    Eysker, M; Boersema, J H; Cornelissen, J B; Kooyman, F N; de Leeuw, W A; Saatkamp, H W

    1993-03-01

    An experiment was carried out with three groups of grazing calves and one housed control group to study the effect of rotational grazing for periods of 1 and 2 weeks on the build up of lungworm and gastro-intestinal nematode infections respectively. The experiment demonstrated that rotational grazing for periods of 1 week on six plots prevented the build-up of heavy lungworm infections. A build up of heavier lungworm infections was observed in a group that was rotationally grazed for periods of 2 weeks on three plots and a group which remained on one plot throughout the grazing season; there was no difference between these two groups. In all three situations, there was an adequate development of immunity against D. viviparus, as measured by worm recovery after challenge infection at the end of the experiment in comparison with worm recovery of the similarly challenged control group. Neither rotational grazing scheme protected the calves against gastrointestinal helminthiasis, because tracer calves, which grazed for 4 days only in August or October, acquired infections which would have resulted in severe illness or even death if necropsy had been postponed for a week.

  19. Mass transfer characterization of gamma-aminobutyric acid production by Enterococcus faecium CFR 3003: encapsulation improves its survival under simulated gastro-intestinal conditions.

    PubMed

    Divyashri, Gangaraju; Prapulla, Siddalingaiya Gurudatt

    2015-03-01

    Gamma-aminobutyric acid (GABA) production by free and Ca-alginate encapsulated cells of Enterococcus faecium CFR 3003 was investigated. Mass transfer rates characterizing the GABA production process using encapsulated cells were investigated. Experiments were performed to investigate external film and internal pore diffusion mass transfer rates. The Damkohler and Thiele analysis provides a good description of external film and internal pore diffusion resistances, respectively. The experiments revealed that the external film effects could be neglected but the process is affected to the greater extent by internal mass transfer effects and was found to be the principal rate-controlling step. Protective effect of encapsulation on cell survivability was tested under digestive environment, when challenged to salivary α-amylase, simulated gastric fluid and intestinal fluid. Viability of encapsulated cells was significantly higher under simulated gastro-intestinal conditions and could produce higher GABA than those observed with free cells. The results indicate that the Ca-alginate encapsulated probiotics could effectively be delivered to the colonic site for effective inhibitory action.

  20. Evaluation of Enterococcus mundtii ST4SA and Lactobacillus plantarum 423 as probiotics by using a gastro-intestinal model with infant milk formulations as substrate.

    PubMed

    Botes, Marelize; van Reenen, Carol A; Dicks, Leon M T

    2008-12-10

    Enterococcus mundtii ST4SA and Lactobacillus plantarum 423 produce bacteriocins with activity against a number of Gram-positive and Gram-negative bacteria. Both strains survived intestinal conditions simulated in a gastro-intestinal model (GIM) with infant milk formulations as substrate and prevented the growth of Listeria monocytogenes ScottA. The strains are inhibited by the antibiotics amoxicillin, cefadroxil, roxithromycin and doxycycline, anti-inflammatory medicaments containing meloxicam, ibuprofen and sodium diklofenak, and analgesics containing paracetamol, codeine phosphate and promethazine. Strain 423 is sensitive to vancomycin and does not contain genes encoding gelatinase, cell aggregation substance (AS), adhesion to collagen (Ace), enterococcus surface protein (Esp), Enterococcus faecalis endocarditis antigen (EfaAfs), cytolysin and non-cytolysin (beta-hemolysin III). Genes encoding AS, cytolysin and non-cytolysin (beta-hemolysin III) were amplified from the genome of strain ST4SA. Survival of strains ST4SA and 423 improved when used as combined cultures in the GIM and compared well with the survival of commercially available probiotics subjected to the same conditions.

  1. Protein breakdown and release of β-casomorphins during in vitro gastro-intestinal digestion of sterilised model systems of liquid infant formula.

    PubMed

    Cattaneo, Stefano; Stuknytė, Milda; Masotti, Fabio; De Noni, Ivano

    2017-02-15

    Protein modifications occurring during sterilisation of infant formulas can affect protein digestibility and release of bioactive peptides. The effect of glycation and cross-linking on protein breakdown and release of β-casomorphins was evaluated during in vitro gastro-intestinal digestion (GID) of six sterilised model systems of infant formula. Protein degradation during in vitro GID was evaluated by SDS-PAGE and by measuring the nitrogen content of ultrafiltration (3kDa) permeates before and after in vitro GID of model IFs. Glycation strongly hindered protein breakdown, whereas cross-linking resulting from β-elimination reactions had a negligible effect. Only β-casomorphin 7 (β-CM7) was detected (0.187-0.858mgL(-1)) at the end of the intestinal digestion in all untreated IF model systems. The level of β-CM7 in the sterilised model systems prepared without addition of sugars ranged from 0.256 to 0.655mgL(-1). The release of this peptide during GID was hindered by protein glycation.

  2. Plant-expressed Hepatitis B core antigen virus-like particles: Characterization and investigation of their stability in simulated and pig gastro-intestinal fluids.

    PubMed

    Berardi, Alberto; Lomonossoff, George P; Evans, David J; Barker, Susan A

    2017-04-30

    Virus-like particles (VLPs) are potential oral vaccine candidates, as their highly compact structure may allow them to withstand the harsh conditions of the gastro-intestinal (GI) environment. Hepatitis B core antigen (HBcAg) is an immunogenic protein that assembles into 30 or 34nm diameter VLPs. Here, the stabilities of both the HBcAg polypeptide itself and the three-dimensional structure of the VLPs upon exposure to in vitro and ex vivo simulated gastric and intestinal fluids were investigated. Plant-expressed HBcAg VLPs were efficiently purified by sucrose density gradient and characterized. The purified VLPs did not show major chemical or physical instability upon exposure to the low pH conditions typically found in the stomach; however, they completely agglomerated upon acidification and subsequent pH neutralization. The HBcAg polypeptide was highly digested upon exposure to pepsin in simulated gastric fluids. HBcAg appeared more stable in both simulated and ex vivo intestinal fluids, where despite a partial digestion of the HBcAg polypeptide, the VLPs maintained their most immunogenic epitopes and their particulate conformation. These results suggest that HBcAg VLPs are likely to be unstable in gastric fluids, yet if the gastric instability could be bypassed, they could maintain their particulate structure and immunogenicity in intestinal fluids. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Effect of gastro-intestinal nematode infection on sheep performance: a systematic review and meta-analysis.

    PubMed

    Mavrot, Fabien; Hertzberg, Hubertus; Torgerson, Paul

    2015-10-24

    Gastrointestinal nematode (GIN) infections are common in domestic sheep and impact directly and indirectly on the health of infected animals as well as on the associated economic production. In this study, we aim at summarizing the current knowledge on the influence of GIN infections on sheep production by conducting a systematic review. A subsequent meta-analysis of relevant studies was performed to provide an estimate of the effect of GIN infections on weight gain, wool production and milk yield. A literature search was performed on the CAB, Pubmed and Web of Science database for the period 1960-2012. Inclusion criteria were: 1) Measurement of at least one production parameter. 2) Comparison between groups of sheep with different nematode burdens. 3) Same conditions regarding all aspects except parasite burden between groups. 4) Quantitative measurements of one or more production traits. Altogether, 88 studies describing 218 trials were included in this review. The majority of studies (86%) reported that GIN infections had a negative effect on production but this was reported to be statistically significant in only 43% of the studies. Meta-analysis indicated that performances of sheep infected with nematodes was 85, 90 and 78% of the performance in uninfected individuals for weight gain, wool production and milk yield respectively. Our results suggest a possible reporting bias or small study effect for the estimation of the impact of GIN infections on weight gain. Finally, a general linear model provided an estimate for the decrease in weight gain in relation to the increase in faecal egg count of nematodes. This study underlines the importance of GIN infections for sheep production and highlights the need to improve parasite management in sheep, in particular in face of challenges such as anthelmintic resistance.

  4. Microentrapment of probiotic bacteria in a Ca(2+)-induced whey protein gel and effects on their viability in a dynamic gastro-intestinal model.

    PubMed

    Ainsley Reid, A; Vuillemard, J C; Britten, M; Arcand, Y; Farnworth, E; Champagne, C P

    2005-09-01

    Entrapping probiotic bacteria in gels with ionic cross-linking is typically achieved with polysaccharides (alginate, pectin, carraghenan). In this study, whey proteins were used for this purpose by carrying out the Ca(2+)-induced gelation of pre-heated whey protein isolate (WPI). A Lactobacillus rhamnosus cell suspension was added in a denatured WPI solution in a 30 : 70 volume ratio. Gelation was carried out by extrusion of the cell suspension in a CaCl(2) solution. Beads of approximately 3 mm diameter were formed. The population in the beads was 8.0 x 10(8) cells g(-1). Entrapment efficiency in gel beads was 96%, with a survival level of 23%. Scanning electron microscopy of beads before freeze-drying showed a tight protein network containing encapsulated Lb. rhamnosus cells homogeneously distributed throughout the matrix. The survival to freeze-drying of the bead-entrapped cells was 41%. Viability of microentrapped cells in a dynamic gastro-intestinal (GI) model was studied and the results were compared to free cells freeze-dried in a milk-based cryoprotective solution, as well as in a pre-denatured WPI solution. Results showed that protein gelation provided protection against acidic conditions in the stomach after 90 min, as well as against bile after 30, 60 and 90 min in the duodenum. Moreover, the milk-based cryoprotective solution was equally effective after 90 min in the duodenum. It is concluded that the gelation of whey proteins induced by Ca(2+) ions can protect the cells against adverse conditions of the GI system. However, certain stages in the entrapment process, particularly extrusion in the solution of CaCl(2), still need to be optimized in order to reduce the mortality of the cells during gelation.

  5. Release of β-casomorphins 5 and 7 during simulated gastro-intestinal digestion of bovine β-casein variants and milk-based infant formulas.

    PubMed

    Noni, Ivano De

    2008-10-15

    The release of β-casomorphin-5 (BCM5) and β-casomorphin-7 (BCM7) was investigated during simulated gastro-intestinal digestion (SGID) of bovine β-casein variants (n=3), commercial milk-based infant formulas (n=6) and experimental infant formulas (n=3). SGID included pepsin digestion at pH 2.0, 3.0 and 4.0 and further hydrolysis with Corolase PP™. β-Casein (β-CN) variants were extracted from raw milks coming from cows of Holstein-Friesian and Jersey breeds. Genomic DNA was isolated from milk and the β-CN genotype was determined by a PCR-based method. Phenotype at protein level was determined by capillary zone electrophoresis in order to ascertain the level of gene expression. Recognition and quantification of BCMs involved HPLC coupled to tandem MS. Regardless of the pH, BCM7 generated from variants A1 and B of β-CN (5-176mmol/mol casein) the highest amount being released during SGID of form B. As expected, the peptide was not released from variant A2 at any steps of SGID. BCM5 was not formed in hydrolysates irrespective of either the genetic variant or the pH value during SGID. Variants A1, A2 and B of β-CN were present in all the commercial infant formulae (IFs) submitted to SGID. Accordingly, 16-297nmol BCM7 were released from 800ml IF, i.e. the daily recommended intake for infant. Industrial indirect-UHT treatments (156°C×6-9s) did not modify release of BCM7 and, during SGID, comparable peptide amounts formed in raw formulation and final heat-treated IFs.

  6. Improving the efficiency of feed utilization in poultry by selection. 1. Genetic parameters of anatomy of the gastro-intestinal tract and digestive efficiency

    PubMed Central

    2011-01-01

    Background Feed costs represent about 70% of the costs of raising broilers. The main way to decrease these costs is to improve feed efficiency by modification of diet formulation, but one other possibility would be to use genetic selection. Understanding the genetic architecture of the gastro-intestinal tract (GIT) and the impact of the selection criterion on the GIT would be of particular interest. We therefore studied the genetic parameters of AMEn (Apparent metabolisable energy corrected for zero nitrogen balance), feed efficiency, and GIT traits in chickens. Genetic parameters were estimated for 630 broiler chickens of the eighth generation of a divergent selection experiment on AMEn. Birds were reared until 23 d of age and fed a wheat-based diet. The traits measured were body weight (BW), feed conversion ratio (FCR), AMEn, weights of crop, liver, gizzard and proventriculus, and weight, length and density of the duodenum, jejunum and ileum. Results The heritability estimates of BW, FCR and AMEn were moderate. The heritability estimates were higher for the GIT characteristics except for the weights of the proventriculus and liver. Gizzard weight was negatively correlated with density (weight to length ratio) of duodenum, jejunum and ileum. Proventriculus and gizzard weights were more strongly correlated with AMEn than with FCR, which was not the case for intestine weight and density. Conclusions GIT traits were largely dependent on genetics and that selecting on AMEn or FCR would modify them. Phenotypic observations carried out in the divergent lines selected on AMEn were consistent with estimated genetic correlations between AMEn and GIT traits. PMID:21733156

  7. Effect of a 12-week integrative oncology intervention on gastro-intestinal concerns in patients with gynecological and breast cancer undergoing chemotherapy.

    PubMed

    Shalom-Sharabi, Ilanit; Keinan-Boker, Lital; Samuels, Noah; Lavie, Ofer; Lev, Efraim; Ben-Arye, Eran

    2017-09-01

    Research on the long-term effects of complementary and integrative medicine (CIM) is limited. In this study, we explore the impact of a CIM intervention on gastro-intestinal (GI)-related concerns in patients with breast/gynecological cancer undergoing chemotherapy. Patients reporting chemotherapy-related GI concerns were referred by their cancer care providers to a CIM consultation and treatments and assessed at baseline and at 12 weeks. The following tools were used: Edmonton Symptom Assessment Scale (ESAS), Measure Yourself Concerns and Wellbeing (MYCAW) and European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30). The intervention group was subdivided according to adherence to the integrative care program (AIC), defined as attending ≥4 CIM treatments with ≤30 days between each session. Controls chose not to undergo the CIM consultation or treatments. Of 289 patients reporting GI-related concerns, 42 were treated with CIM and optimally assessed (intervention arm; AIC = 33), as were 32 of controls. ESAS scores for appetite and nausea improved more significantly in the intervention group, more so in the AIC subgroup (appetite, p = 0.025; nausea, p = 0.033). MYCAW scores for GI-related concerns also improved in the intervention group, again more so in the adherent subgroup. EORTC scores improved more significantly with respect to global health (p = 0.021) and cognitive functioning (p = 0.031) in the intervention group, when compared to controls. The integration of a 12-week CIM intervention in conventional supportive cancer care may reduce nausea and improve appetite in patients with breast/gynecological cancer undergoing chemotherapy.

  8. Beneficial Effects of Simulated Gastro-Intestinal Digests of Fried Egg and Its Fractions on Blood Pressure, Plasma Lipids and Oxidative Stress in Spontaneously Hypertensive Rats

    PubMed Central

    Chakrabarti, Subhadeep; Morton, Jude S.; Panahi, Sareh; Kaufman, Susan; Davidge, Sandra T.; Wu, Jianping

    2014-01-01

    Abstract Background We have previously characterized several antihypertensive peptides in simulated digests of cooked eggs and showed blood pressure lowering property of fried whole egg digest. However, the long-term effects of this hydrolysate and its fractions on blood pressure are not known. Therefore, the objectives of the study were to determine the effects of long term administration of fried whole egg hydrolysate and its fractions (i.e. egg white and egg yolk) on regulation of blood pressure and associated factors in cardiovascular disease such as plasma lipid profile and tissue oxidative stress. Methods and Results We used spontaneously hypertensive rats (SHR), an animal model of essential hypertension. Hydrolysates of fried egg and its fractions were prepared by simulated gastro-intestinal digestion with pepsin and pancreatin. 16–17 week old male SHRs were orally administered fried whole egg hydrolysate, non-hydrolyzed fried whole egg, egg white hydrolysate or egg yolk hydrolysates (either defatted, or not) daily for 18 days. Blood pressure (BP) and heart rate were monitored by telemetry. Animals were sacrificed at the end of the treatment for vascular function studies and evaluating plasma lipid profile and tissue oxidative stress. BP was reduced by feeding fried whole egg hydrolysate but not by the non-hydrolyzed product suggesting a critical role for in vitro digestion in releasing anti-hypertensive peptides. Egg white hydrolysate and defatted egg yolk hydrolysate (but not egg yolk hydrolysate) also had similar effects. Reduction in BP was accompanied by the restoration of nitric oxide (NO) dependent vasorelaxation and reduction of plasma angiotensin II. Fried whole egg hydrolysate also reduced plasma levels of triglyceride although it was increased by the non-hydrolyzed sample. Additionally the hydrolyzed preparations attenuated tissue oxidative stress. Conclusion Our results demonstrate that fried egg hydrolysates exert anti-hypertensive effects

  9. Isoenergetic Replacement of Fat by Starch in Diets for African Catfish (Clarias gariepinus): Effect on Water Fluxes in the Gastro Intestinal Tract

    PubMed Central

    Harter, Till S.; Verreth, Johan A. J.; Heinsbroek, Leon T. N.; Schrama, Johan W.

    2013-01-01

    The effect of an isoenergetic replacement of dietary fat by starch, on chyme characteristics and water fluxes in the gastro intestinal tract (GIT) was assessed. Adult African catfish (Clarias gariepinus) were fed a starch (SD) or fat (FD) diet and groups of fish were dissected at 2, 5 and 8 h after the consumption of a single meal. Chyme was collected quantitatively and was analysed for osmolality and dry matter (DM) content. Postprandial water fluxes were calculated, while using yttrium oxide (Y2O3) as an inert marker to account for the absorption of DM along the GIT. The largest differences in chyme characteristics between diets were observed in the stomach and decreased towards subsequent compartments. A high initial osmotic pressure was measured in the stomach for both diets (up to 498±2 mOsm kg−1) and was likely the driver for the endogeneous water influx to this compartment. Large additions of water were recorded to the stomach and proximal intestine for both diets and absorption of water took place in the mid- and distal intestine. Interestingly, the dietary treatment had an impact on water balance in the stomach and proximal intestine of the fish, but not in the mid- and distal intestine. A strong complementary relationship suggested that 59% of the water fluxes in the proximal intestine could be explained by previous additions to the stomach. Therefore, a higher dietary inclusion of starch led to a shift in water additions from the proximal intestine to the stomach. However, the sum of water additions to the GIT was not different between diets and was on average 6.52±0.85 ml water g−1 DM. The interactions between osmoregulation and digestion, in the GIT of fed freshwater fish, deserve further attention in future research. PMID:23372842

  10. Fed and fasted state gastro-intestinal in vitro lipolysis: In vitro in vivo relations of a conventional tablet, a SNEDDS and a solidified SNEDDS.

    PubMed

    Christophersen, Philip Carsten; Christiansen, Martin Lau; Holm, Rene; Kristensen, Jakob; Jacobsen, Jette; Abrahamsson, Bertil; Müllertz, Anette

    2014-06-16

    The present study aims at evaluating the ability of a gastro-intestinal in vitro lipolysis model to predict the performance of two lipid formulations and a conventional tablet containing a poorly soluble drug, cinnarizine, in dogs, both in the fasted and fed state. A self-nano-emulsifying drug delivery system (SNEDDS) was either dosed in a hard gelatin capsule (SNEDDS-C) or loaded onto a porous tablet core (SNEDDS-T) and compared to a marketed conventional tablet (Conv) in an in vitro lipolysis model. The model simulates the digestion in the stomach and intestine during either the fasted or the fed state. Whole fat milk (3.5%) was used in the fed state model to mimic the dynamic lipolysis events after ingestion of food. The results were compared to a dog study published in this issue. In the fasted state in vitro lipolysis model, the amount of solubilized cinnarizine decreased in the order SNEDDS-C>SNEDDS-T>Conv, which correlated well with the in vivo bioavailability. In the fed state in vitro lipolysis model, cinnarizine was solubilized to the same degree for all formulations. Compared to the fasted state model, only the performance of the conventional tablet was improved, indicating food effect. This correlated with the in vivo study, where the tablet was the only formulation with a significant food effect. The fasted state model correlated well with the in vivo results and although the fed state model did not accurately predict the fed state in vivo results, it could predict which formulation that would exhibit a food effect.

  11. Improving the efficiency of feed utilization in poultry by selection. 1. Genetic parameters of anatomy of the gastro-intestinal tract and digestive efficiency.

    PubMed

    de Verdal, Hugues; Narcy, Agnès; Bastianelli, Denis; Chapuis, Hervé; Même, Nathalie; Urvoix, Séverine; Le Bihan-Duval, Elisabeth; Mignon-Grasteau, Sandrine

    2011-07-06

    Feed costs represent about 70% of the costs of raising broilers. The main way to decrease these costs is to improve feed efficiency by modification of diet formulation, but one other possibility would be to use genetic selection. Understanding the genetic architecture of the gastro-intestinal tract (GIT) and the impact of the selection criterion on the GIT would be of particular interest. We therefore studied the genetic parameters of AMEn (Apparent metabolisable energy corrected for zero nitrogen balance), feed efficiency, and GIT traits in chickens.Genetic parameters were estimated for 630 broiler chickens of the eighth generation of a divergent selection experiment on AMEn. Birds were reared until 23 d of age and fed a wheat-based diet. The traits measured were body weight (BW), feed conversion ratio (FCR), AMEn, weights of crop, liver, gizzard and proventriculus, and weight, length and density of the duodenum, jejunum and ileum. The heritability estimates of BW, FCR and AMEn were moderate. The heritability estimates were higher for the GIT characteristics except for the weights of the proventriculus and liver. Gizzard weight was negatively correlated with density (weight to length ratio) of duodenum, jejunum and ileum. Proventriculus and gizzard weights were more strongly correlated with AMEn than with FCR, which was not the case for intestine weight and density. GIT traits were largely dependent on genetics and that selecting on AMEn or FCR would modify them. Phenotypic observations carried out in the divergent lines selected on AMEn were consistent with estimated genetic correlations between AMEn and GIT traits.

  12. Negative effects of divalent mineral cations on the bioaccessibility of carotenoids from plant food matrices and related physical properties of gastro-intestinal fluids.

    PubMed

    Corte-Real, Joana; Bertucci, Marie; Soukoulis, Christos; Desmarchelier, Charles; Borel, Patrick; Richling, Elke; Hoffmann, Lucien; Bohn, Torsten

    2017-03-22

    Carotenoid intake and tissue levels have been frequently associated with reduced risk of chronic diseases. However, their bioavailability is low and influenced by many dietary related parameters. Divalent mineral cations have been suggested to interfere with carotenoid digestion and to hamper micellarization, a prerequisite for their uptake, via complexation of bile salts and precipitation of fatty acids. In the present investigation, we have evaluated the effects of increasing concentrations of magnesium (0-300 mg L(-1)), calcium (0-1500 mg L(-1)), zinc (0-200 mg L(-1)), and sodium (0-1500 mg L(-1); control monovalent cation), on carotenoid bioaccessibility from frequently consumed food items rich in carotenoids (tomato juice, carrot juice, apricot nectar, spinach and field salad), following simulated gastro-intestinal digestion. In addition, physicochemical parameters of digesta (macroviscosity, surface tension), micelle size, and zeta-potential were evaluated. All divalent minerals (DM) reduced bioaccessibility of total carotenoids (P < 0.01), as well as of individual carotenoids. Calcium and magnesium led to reductions of up to 100% at the 2 highest concentrations. Curiously, sodium increased (P < 0.01) carotenoid bioaccessiblity of most investigated matrices. The absolute value of the zeta-potential decreased with increasing concentrations of DM, suggesting a decreased stability of the colloidal digesta dispersion. Viscosity decreased, except for apricot nectar samples, while surface tension increased with DM concentration (P < 0.05). Thus, at physiological ranges, calcium and magnesium could negatively impact carotenoid bioavailability, while for zinc, negative effects were only seen at supplemental concentrations. The potential negative effects of DM on carotenoid bioavailability should be further studied in vivo.

  13. Beneficial effects of simulated gastro-intestinal digests of fried egg and its fractions on blood pressure, plasma lipids and oxidative stress in spontaneously hypertensive rats.

    PubMed

    Jahandideh, Forough; Majumder, Kaustav; Chakrabarti, Subhadeep; Morton, Jude S; Panahi, Sareh; Kaufman, Susan; Davidge, Sandra T; Wu, Jianping

    2014-01-01

    We have previously characterized several antihypertensive peptides in simulated digests of cooked eggs and showed blood pressure lowering property of fried whole egg digest. However, the long-term effects of this hydrolysate and its fractions on blood pressure are not known. Therefore, the objectives of the study were to determine the effects of long term administration of fried whole egg hydrolysate and its fractions (i.e. egg white and egg yolk) on regulation of blood pressure and associated factors in cardiovascular disease such as plasma lipid profile and tissue oxidative stress. We used spontaneously hypertensive rats (SHR), an animal model of essential hypertension. Hydrolysates of fried egg and its fractions were prepared by simulated gastro-intestinal digestion with pepsin and pancreatin. 16-17 week old male SHRs were orally administered fried whole egg hydrolysate, non-hydrolyzed fried whole egg, egg white hydrolysate or egg yolk hydrolysates (either defatted, or not) daily for 18 days. Blood pressure (BP) and heart rate were monitored by telemetry. Animals were sacrificed at the end of the treatment for vascular function studies and evaluating plasma lipid profile and tissue oxidative stress. BP was reduced by feeding fried whole egg hydrolysate but not by the non-hydrolyzed product suggesting a critical role for in vitro digestion in releasing anti-hypertensive peptides. Egg white hydrolysate and defatted egg yolk hydrolysate (but not egg yolk hydrolysate) also had similar effects. Reduction in BP was accompanied by the restoration of nitric oxide (NO) dependent vasorelaxation and reduction of plasma angiotensin II. Fried whole egg hydrolysate also reduced plasma levels of triglyceride although it was increased by the non-hydrolyzed sample. Additionally the hydrolyzed preparations attenuated tissue oxidative stress. Our results demonstrate that fried egg hydrolysates exert anti-hypertensive effects, improve plasma lipid profile and attenuate tissue

  14. Parasites

    MedlinePlus

    ... Where to Find Further Information on Parasitic Diseases Public Health Image Library Freedom of Information Act (FOIA) Explore Parasites A-Z Index Parasites Glossary Education and Training Healthy Water Travelers Health Laboratory ... Science Parasites About Parasites Animals ...

  15. Electromyoenterography During Normal Gastro-Intestinal Activity, Painful or Non-painful Colic and Morphine Analgesia, in the Horse

    PubMed Central

    Phaneuf, L. P.; Grivel, M. L.; Ruckebusch, Y.

    1972-01-01

    The electrical potentials were recorded from the antrum, the duodenum, the ileum and the first part of the colon of ponies under (a) normal resting conditions, (b) during nonpainful colic and (c) after intravenous morphine administration. The normal pony, at rest, had five contractions of the antrum per minute. On the small intestine, the basal electrical activity decreased from the duodenum (14-15/min) to the ileum (10-11/min). The small bowel also had three types of motility: peristaltic waves, rhythmic segmentations and random contractions. On the colon, bursts of potentials indicating intense motor activity occurred at the rate of 20 to 30 per hour. Morphine given intravenously (IV) greatly increased the frequency of the electrical potentials of the antrum and the longitudinal bands of the colon. During non-painful colic, hyperactivity of the cranial small intestine was continuous. Spasms of the jejunum occurred every minute and could not be relieved by morphine (IV). When colic was painful, jejunal spasms announced the crisis of intense abdominal pain. After morphine (IV) the spasms and pain disappeared; the jejunum remained hyperactive, the motility of the colon was increased while the antrum became quiet. ImagesFig. 3.Fig. 4. PMID:4259927

  16. Identification of quantitative trait loci affecting resistance to gastro-intestinal parasites in a double backcross population of Red Maasai and Dorper sheep

    USDA-ARS?s Scientific Manuscript database

    A genome-wide scan for quantitative trait loci (QTL) affecting gastrointestinal (GI) nematode resistance was completed using a double backcross sheep population derived from Red Maasai and Dorper ewes bred to F1 rams. These breeds were chosen, because Red Maasai sheep are known to be more tolerant ...

  17. Alleviating gastro-intestinal symptoms and concerns by integrating patient-tailored complementary medicine in supportive cancer care.

    PubMed

    Ben-Arye, Eran; Aharonson, Michal Livne; Schiff, Elad; Samuels, Noah

    2015-12-01

    Chemotherapy-induced gastrointestinal (GI) toxicities often impair quality-of-life (QOL) and require reduction of the chemotherapy dose intensity. We explored the effects of a complementary integrative medicine (CIM) therapeutic process, administered in conjunction with conventional supportive care, on GI-related symptoms and concerns in patients undergoing chemotherapy. We conducted a prospective, pragmatic study among patients undergoing chemotherapy referred by their healthcare providers to a CIM-trained integrative physician (IP) for consultation, followed by CIM treatments. Symptom severity and patient concerns were assessed at baseline and at an IP follow-up visit at 6-12 weeks, using the Edmonton Symptom Assessment Scale (ESAS) and the Measure Yourself Concerns and Wellbeing (MYCAW) questionnaires. Adherence to the integrative care (AIC) program was defined as attendance of ≥4 CIM treatments, with ≤30 days between sessions. Of the 308 patients referred to the IP consultation, 275 (89.3%) expressed GI symptoms and concerns, 189 of whom attended the follow-up IP assessment. Of these, 144 (46%) were found to be adherent to the treatment plan (AIC group). Repeated measure analysis indicated a statistical interaction between baseline and follow-up scores, for ESAS (appetite, p = 0.005; drowsiness, p = 0.027; shortness of breath, p = 0.027; and sleep, p = 0.034) and for MYCAW outcomes. This when comparing the AIC to the non-AIC group responses. Reduction of GI concerns (p = 0.024) was greater among patients in the AIC group (MYCAW questionnaire), with significantly less chemotherapy-related hospitalizations found in this group (p = 0.008). The participation of a registered dietitian during CIM treatments led to greater reduction in nausea (from 4.24 to 1.85 vs. 2.73 to 1.36, respectively; p = 0.017). Integration of CIM with standard supportive care, especially in patients adhering to the CIM treatment regimen, may help reduce chemotherapy-induced GI symptoms

  18. A 12-month survey of the gastro-intestinal helminths of antelopes, gazelles and giraffids kept at two zoos in Belgium.

    PubMed

    Goossens, Els; Dorny, Pierre; Boomker, Joop; Vercammen, Francis; Vercruysse, Jozef

    2005-02-28

    Faecal egg count patterns and clinical signs associated with gastro-intestinal (GI) nematodes of 107 zoo ruminants were monitored at fortnightly intervals for 1 year. The ruminants in this study were kept under different husbandry conditions at two sites of the Royal Zoological Society of Antwerp, the Antwerp Zoo and the Animal Park Planckendael. Artiodactylids involved were Arabian oryx (Oryx leucoryx), scimitar-horned oryx (Oryx dammah), bongos (Tragelaphus euryceros isaaci), sitatungas (Tragelaphus spekii gratus), common eland (Taurotragus oryx), impala (Aepyceros melampus), slender-horned gazelles, (Gazella leptoceros), blue wildebeest (Connochaetes taurinus taurinus), Kordofan giraffes (Giraffe camelopardalis antiquorum) and okapi (Okapia johnstoni). Nematode eggs were recovered from 586 of 1606 (36.5%) individual faecal samples, using flotation techniques. Infection levels were distinctly low at Antwerp Zoo, probably due to zero grazing and daily dung removal. At Planckendael, the herds of Arabian oryx, scimitar-horned oryx and slender-horned gazelles showed markedly higher egg counts than the other herds, with more than 10% of the faecal egg counts having more than 100 eggs per gram (epg) and maximum faecal egg counts of 600, 750 and 1350 epg, respectively. Faecal egg counts increased during the mid-grazing season (July) and peaked at the end of the grazing season (October). No clinical signs, such as loss of faecal consistency, could be correlated with faecal egg counts (P > 0.05). With the exception of significantly more Nematodirus spp. eggs that were present in juvenile eland, no differences in faecal egg counts could be found between the sexes and different age groups. Abomasa and intestines of 17 animals that died during the survey were available for total worm counts. In one Arabian oryx, four slender-horned gazelles and one sitatunga low burdens ranging from 200 to 14,300 were found. Nematode species recovered were Camelostrongylus mentulatus from

  19. [Prevalence and parasitism intensity by Pediculus humanus capitis in six to eleven-year-old schoolchildren].

    PubMed

    Catalá, Silvia; Carrizo, Lorena; Córdoba, Marina; Khairallah, Roxana; Moschella, Fabrizio; Bocca, Julio Nacif; Calvo, Ana Nieto; Torres, Judiht; Tutino, Rodrigo

    2004-01-01

    The aim of this work was to determine head lice parasitism intensity by Pediculus humanus capitis and its variation, according to both gender and age in 181 school children of a primary school. The intensity was higher among 6 to 8-year-old girls. Pediculosis intensity diminishes significantly between 9 and 11 years of age in both sexes.

  20. Headspace screening of fluid obtained from the gut during colonoscopy and breath analysis by proton transfer reaction-mass spectrometry: A novel approach in the diagnosis of gastro-intestinal diseases

    NASA Astrophysics Data System (ADS)

    Lechner, M.; Colvin, H. P.; Ginzel, C.; Lirk, P.; Rieder, J.; Tilg, H.

    2005-05-01

    Background: The diagnosis of many gastro-intestinal diseases is difficult and can often be confirmed only by using invasive diagnostic means. In contrast, the headspace screening of fluid obtained from the gut during colonoscopy and the analysis of exhaled air may be a novel approach for the diagnosis of these diseases.Materials and methods: The screening was performed by using proton transfer reaction-mass spectrometry (PTR-MS) which allows rapid and sensitive measurement. Fluid samples obtained from the gut during colonoscopy were collected from 76 and breath samples from 70 subjects. Mass spectra of healthy controls were created. Afterwards these spectra were compared with those of patients suffering from inflammatory bowel diseases (IBD; Crohn's disease and ulcerative colitis; n = 10) and irritable bowel syndrome (IBS; n = 7).Results: Significant differences in the mass spectra could be observed both in the headspace of the fluid and in the exhaled air comparing patients with healthy controls.Conclusions: This study is the first describing headspace screening of fluid obtained from the gut during colonoscopy, possibly presenting a novel diagnostic tool in the differential diagnosis of gastro-intestinal diseases.

  1. Parasites and carotenoid-based signal intensity: how general should the relationship be?

    PubMed

    Shykoff, J A; Widmer, A

    1996-03-01

    Evidence that selection by parasites maintains heritable variation in sexually selected signals (Hamilton-Zuk model) has proved equivocal. Bright individuals do not always have fewer parasites in intraspecific comparisons. Because the lymphocyte-based defence system and the production of some colors used in sexual signaling require carotenoids, we consider a trade-off between defence against parasites and sexual signals. The nature and the sign of the covariance between defence and signal brightness can vary. Depending on carotenoid availability and allocation, and the type of sexual signal, various relationships between parasite load and signal intensity are expected.

  2. Exploring the Gastrointestinal “Nemabiome”: Deep Amplicon Sequencing to Quantify the Species Composition of Parasitic Nematode Communities

    PubMed Central

    Avramenko, Russell W.; Redman, Elizabeth M.; Lewis, Roy; Yazwinski, Thomas A.; Wasmuth, James D.; Gilleard, John S.

    2015-01-01

    Parasitic helminth infections have a considerable impact on global human health as well as animal welfare and production. Although co-infection with multiple parasite species within a host is common, there is a dearth of tools with which to study the composition of these complex parasite communities. Helminth species vary in their pathogenicity, epidemiology and drug sensitivity and the interactions that occur between co-infecting species and their hosts are poorly understood. We describe the first application of deep amplicon sequencing to study parasitic nematode communities as well as introduce the concept of the gastro-intestinal “nemabiome”. The approach is analogous to 16S rDNA deep sequencing used to explore microbial communities, but utilizes the nematode ITS-2 rDNA locus instead. Gastro-intestinal parasites of cattle were used to develop the concept, as this host has many well-defined gastro-intestinal nematode species that commonly occur as complex co-infections. Further, the availability of pure mono-parasite populations from experimentally infected cattle allowed us to prepare mock parasite communities to determine, and correct for, species representation biases in the sequence data. We demonstrate that, once these biases have been corrected, accurate relative quantitation of gastro-intestinal parasitic nematode communities in cattle fecal samples can be achieved. We have validated the accuracy of the method applied to field-samples by comparing the results of detailed morphological examination of L3 larvae populations with those of the sequencing assay. The results illustrate the insights that can be gained into the species composition of parasite communities, using grazing cattle in the mid-west USA as an example. However, both the technical approach and the concept of the ‘nemabiome’ have a wide range of potential applications in human and veterinary medicine. These include investigations of host-parasite and parasite-parasite interactions

  3. Climate-driven tipping-points could lead to sudden, high-intensity parasite outbreaks

    PubMed Central

    Fox, Naomi J.; Marion, Glenn; Davidson, Ross S.; White, Piran C. L.; Hutchings, Michael R.

    2015-01-01

    Parasitic nematodes represent one of the most pervasive and significant challenges to grazing livestock, and their intensity and distribution are strongly influenced by climate. Parasite levels and species composition have already shifted under climate change, with nematode parasite intensity frequently low in newly colonized areas, but sudden large-scale outbreaks are becoming increasingly common. These outbreaks compromise both food security and animal welfare, yet there is a paucity of predictions on how climate change will influence livestock parasites. This study aims to assess how climate change can affect parasite risk. Using a process-based approach, we determine how changes in temperature-sensitive elements of outbreaks influence parasite dynamics, to explore the potential for climate change to influence livestock helminth infections. We show that changes in temperate-sensitive parameters can result in nonlinear responses in outbreak dynamics, leading to distinct ‘tipping-points’ in nematode parasite burdens. Through applying two mechanistic models, of varying complexity, our approach demonstrates that these nonlinear responses are robust to the inclusion of a number of realistic processes that are present in livestock systems. Our study demonstrates that small changes in climatic conditions around critical thresholds may result in dramatic changes in parasite burdens. PMID:26064647

  4. Climate-driven tipping-points could lead to sudden, high-intensity parasite outbreaks.

    PubMed

    Fox, Naomi J; Marion, Glenn; Davidson, Ross S; White, Piran C L; Hutchings, Michael R

    2015-05-01

    Parasitic nematodes represent one of the most pervasive and significant challenges to grazing livestock, and their intensity and distribution are strongly influenced by climate. Parasite levels and species composition have already shifted under climate change, with nematode parasite intensity frequently low in newly colonized areas, but sudden large-scale outbreaks are becoming increasingly common. These outbreaks compromise both food security and animal welfare, yet there is a paucity of predictions on how climate change will influence livestock parasites. This study aims to assess how climate change can affect parasite risk. Using a process-based approach, we determine how changes in temperature-sensitive elements of outbreaks influence parasite dynamics, to explore the potential for climate change to influence livestock helminth infections. We show that changes in temperate-sensitive parameters can result in nonlinear responses in outbreak dynamics, leading to distinct 'tipping-points' in nematode parasite burdens. Through applying two mechanistic models, of varying complexity, our approach demonstrates that these nonlinear responses are robust to the inclusion of a number of realistic processes that are present in livestock systems. Our study demonstrates that small changes in climatic conditions around critical thresholds may result in dramatic changes in parasite burdens.

  5. Detecting and quantifying parasite-induced host mortality from intensity data: method comparisons and limitations.

    PubMed

    Wilber, Mark Q; Weinstein, Sara B; Briggs, Cheryl J

    2016-01-01

    Parasites can significantly impact animal populations by changing host behaviour, reproduction and survival. Detecting and quantifying these impacts is critical for understanding disease dynamics and managing wild animal populations. However, for wild hosts infected with macroparasites, it is notoriously difficult to quantify the fatal parasite load and number of animals that have died due to disease. When ethical or logistical constraints prohibit experimental determination of these values, examination of parasite intensity and distribution data may offer an alternative solution. In this study we introduce a novel method for using intensity data to detect and quantify parasite-induced mortality in wildlife populations. We use simulations to show that this method is more reliable than previously proposed methods while providing quantitative estimates of parasite-induced mortality from empirical data that are consistent with previously published qualitative estimates. However this method, and all techniques that estimate parasite-induced mortality from intensity data alone, have several important assumptions that must be scrutinised before applying those to real-world data. Given that these assumptions are met, our method is a new exploratory tool that can help inform more rigorous studies of parasite-induced host mortality.

  6. Detecting and quantifying parasite-induced host mortality from intensity data: method comparisons and limitations

    PubMed Central

    Wilber, Mark Q.; Weinstein, Sara B.; Briggs, Cheryl J.

    2016-01-01

    Parasites can significantly impact animal populations by changing host behavior, reproduction and survival. Detecting and quantifying these impacts is critical for understanding disease dynamics and managing wild animal populations. However, for wild hosts infected with macroparasites, it is notoriously difficult to quantify the fatal parasite load and number of animals that have died due to disease. When ethical or logistical constraints prohibit experimental determination of these values, examination of parasite intensity and distribution data may offer an alternative solution. In this study we introduce a novel method for using intensity data to detect and quantify parasite-induced mortality in wildlife populations. Using simulations, we show that this method is more reliable than previously proposed methods while providing quantitative estimates of parasite-induced mortality from empirical data that are consistent with previously published qualitative estimates. However, we stress that this method, and all techniques that estimate parasite-induced mortality from intensity data alone, have several critical assumptions that limit their applicability in the real world. Due to these limitations, these methods should only be used as an exploratory tool to inform more rigorous studies of parasite-induced host mortality. PMID:26475963

  7. Parasitic gastro-enteritis in lambs — A model for estimating the timing of the larval emergence peak

    NASA Astrophysics Data System (ADS)

    Starr, J. R.; Thomas, R. J.

    1980-09-01

    The life history of the nematode parasites of domestic ruminants usually involves the development and survival of free-living stages on pasture. The pasture is, therefore, the site of deposition, development and transmission of nematode infection and meteorological factors affecting the pasture will affect the parasites. Recently Thomas and Starr (1978) discussed an empirical technique for forecasting the timing of the summer wave of gastro-intestinal parasitism in North-East England in the lamb crop using meteorological data and in particular estimates of the duration of “surface wetness”. This paper presents an attempt to model “surface wetness” and the temperature limitation to nematode development.

  8. Drivers of Intensity and Prevalence of Flea Parasitism on Small Mammals in East African Savanna Ecosystems.

    PubMed

    Young, Hillary S; Dirzo, Rodolfo; McCauley, Douglas J; Agwanda, Bernard; Cattaneo, Lia; Dittmar, Katharina; Eckerlin, Ralph P; Fleischer, Robert C; Helgen, Lauren E; Hintz, Ashley; Montinieri, John; Zhao, Serena; Helgen, Kristofer M

    2015-06-01

    The relative importance of environmental factors and host factors in explaining variation in prevalence and intensity of flea parasitism in small mammal communities is poorly established. We examined these relationships in an East African savanna landscape, considering multiple host levels: across individuals within a local population, across populations within species, and across species within a landscape. We sampled fleas from 2,672 small mammals of 27 species. This included a total of 8,283 fleas, with 5 genera and 12 species identified. Across individual hosts within a site, both rodent body mass and season affected total intensity of flea infestation, although the explanatory power of these factors was generally modest (<10%). Across host populations in the landscape, we found consistently positive effects of host density and negative effects of vegetation cover on the intensity of flea infestation. Other factors explored (host diversity, annual rainfall, anthropogenic disturbance, and soil properties) tended to have lower and less consistent explanatory power. Across host species in the landscape, we found that host body mass was strongly positively correlated with both prevalence and intensity of flea parasitism, while average robustness of a host species to disturbance was not correlated with flea parasitism. Cumulatively, these results provide insight into the intricate roles of both host and environmental factors in explaining complex patterns of flea parasitism across landscape mosaics.

  9. The prevalence and intensity of gastrointestinal parasites of dogs in Ile-Ife, Nigeria.

    PubMed

    Sowemimo, Oluyomi A

    2009-03-01

    A study of gastrointestinal parasites in 269 faecal samples from dogs (Canis familiaris) collected from Ile-Ife, Nigeria between January and December 2004, revealed seven helminth species: Toxocara canis 33.8%, Ancylostoma sp. 34.6%, Toxascaris leonina 3.3%, Trichuris vulpis 3.7%, Dipylidium caninum 4.1%, Uncinaria stenocephala 0.7% and Taenia sp. 1.1%. The faecal egg intensities, determined as mean eggs per gram of faeces ( +/- SEM) were: T. canis 393.8 +/- 83.4, Ancylostoma sp. 101.5 +/- 32.8, T. leonina 14.3 +/- 7.9, T. vulpis 3.4 +/- 1.5, D. caninum 2.2 +/- 0.8, U. stenocephala 0.2 +/- 0.2. The prevalence of intestinal parasites was significantly higher (P < 0.05) in dogs of age 0-6 months than in older age groups. There was no significance difference in overall prevalence of intestinal helminth parasites between male (58.3%) and female (50.0%) dogs (P>0.05). The prevalence of helminth parasites was significantly higher (P < 0.05) in free-ranging than in kennelled dogs. The prevalence of helminth parasites was also significantly higher (P < 0.05) in African shepherds than in Alsatians and other exotic breeds. Each helminth parasite had similar prevalences and intensities among both genders (P>0.05) except in T. vulpis. The overall prevalence of intestinal parasites may continue to rise due to lack of functional veterinary clinics for dog care in Ile-Ife. Therefore, there is the need to establish a veterinary facility in Ile-Ife.

  10. Parasite age-intensity relationships in red-spotted newts: does immune memory influence salamander disease dynamics?

    PubMed

    Raffel, Thomas R; LeGros, Robert P; Love, Brenda C; Rohr, Jason R; Hudson, Peter J

    2009-01-01

    Acquired immune memory in vertebrates influences transmission and persistence of infections, with consequences for parasite dynamics at both the individual and population levels. The potential impact of acquired immunity is of particular interest for salamanders, whose acquired immune systems are thought to be less effective than those of frogs and other tetrapods. One way to examine the importance of acquired immunity to parasite dynamics at the population level is by examining the relationship between host age and parasite infection intensity. Acquired immunity reduces infection rates in older animals, causing decreased parasite intensity in older age classes and leading to curvilinear age-intensity relationships for persistent parasites and convex age-intensity relationships for transient parasites. We used age-intensity relationships to look for the signature of acquired immunity for 12 parasite taxa of red-spotted newts (Notophthalmus viridescens), using data from a 2-year parasitological survey of six newt populations. We estimated ages from snout-vent length (SVL) based on the relationship between SVL and skeletochronologically-derived ages in a subset of newts. We found evidence of acquired immunity to two parasite taxa, bacterial pathogens and the protist Amphibiocystidium viridescens, whose convex age-intensity relationships could not be easily explained by alternative mechanisms. Our results suggest that the acquired immune response of newts is sufficient to influence the dynamics of at least some parasites.

  11. Association of sub-microscopic malaria parasite carriage with transmission intensity in north-eastern Tanzania

    PubMed Central

    2011-01-01

    Background In malaria endemic areas, individuals are frequently asymptomatic and may be undetected by conventional microscopy or newer, rapid diagnostic tests. Molecular techniques allow a more accurate assessment of this asymptomatic parasite burden, the extent of which is important for malaria control. This study examines the relative prevalence of sub-microscopic level parasite carriage and clonal complexity of infections (multiplicity of infection) over a range of endemicities in a region of north-eastern Tanzania where altitude is an established proxy of malaria transmission. The PCR prevalence was then compared against other measures of transmission intensity collected in the same area. Methods This study used 1,121 blood samples collected from a previously conducted cross-sectional malario-metric survey during the short rainy season in 2001 from 13 villages (three at < 600 m, four at 600-1,200 m and six at > 1,200 m in altitude above sea level). Samples were analysed by PCR for carriage of parasites and multiplicity of infection. These data were compared with other measures of transmission intensity collected from the same area. Results Parasite prevalence was 34.7% by PCR and 13.6% by microscopy; a 2.5-fold difference in line with other recent observations. This fold difference was relatively consistent at the different altitude bands despite a marked decrease in parasite prevalence with altitude: < 600 m 70.9 vs 28.6, 600-1,200 m 35.5 vs 9.9, > 1,200 m 15.8 vs 5.9. The difference between parasite prevalence by PCR was 3.2 in individuals aged between 15 and 45 years (34.5 vs 10.9) compared with 2.5 in those aged 1-5 (34.0 vs 13.5) though this was not statistically significant. Multiplicity of infection (MOI) ranged from 1.2 to 3.7 and was positively associated with parasite prevalence assessed by both PCR and microscopy. There was no association of MOI and age. Village level PCR parasite prevalence was strongly correlated with altitude, sero-conversion rate

  12. Prevalence and intensity of intestinal parasitic infections in relation to nutritional status in Mexican schoolchildren.

    PubMed

    Quihui-Cota, L; Valencia, M E; Crompton, D W T; Phillips, S; Hagan, P; Diaz-Camacho, S P; Triana Tejas, A

    2004-11-01

    Undernutrition and intestinal parasitic infections affect childhood development and morbidity in many developing countries. Undernutrition may increase susceptibility to parasitic infections which in turn impair the nutritional status of the host. The relationship between intestinal parasitic infections and nutritional status in 400 Mexican schoolchildren was investigated. More than half of the children in the study showed intestinal parasites and polyparasitism. The prevalence of helminth infections was significantly higher in Oaxaca than in Sinaloa (P < 0.05). Z scores for weight-for-age (WA) and height-for-age (HA) were much lower in children of Oaxaca than in Sinaloa (P < 0.001). A significantly higher Z score for weight-for-height (WH), WA, and HA were found in non-infected versus infected children (P < 0.05). Higher prevalences of intestinal infections were found in children with lower HA and WA than in normally nourished children (P < 0.05). Higher intensities of Ascaris lumbricoides and Trichuris trichiura were found in the schoolchildren of Sinaloa than in Oaxaca (P < 0.01). Negative and significant associations were found between Hymenolepis nana and T. trichiura infection (eggs per gram) and nutritional status. Intestinal parasitic infections may be regarded as main risk factors associated with poor nutritional status in Mexican schoolchildren.

  13. Parasitic control in intensive vs. non-intensive systems--ruminants.

    PubMed

    Reinecke, R K

    1994-08-01

    The acquisition and intensity of infection with gastrointestinal nematodes and with Oestrus ovis are compared over 2 years in sheep grazed intensively (26-36 sheep ha-1) or non-intensively (12 sheep ha-1) in the winter rainfall Overberg region of South Africa. Sheep grazing intensively on grass/legume pastures, spray irrigated in summer, acquired massive mixed infections of Trichostrongylus, Haemonchus and Teladorsagia. Infections were fatal for sucking lambs. Lambs from ewes grazed non-intensively on dry land lucerne in winter became infected with Nematodirus and then with Teladorsagia and Trichostrongylus spp.; resistance to Nematodirus was apparent after 12 weeks; spontaneous cure of Teladorsagia began in hoggets grazing on safe wheat stubble pasture; but Trichostrongylus survived in the sheep. Helminth-induced host mortality was not observed on the non-intensive farm. The efficacy of various methods of control was examined in the intensively managed sheep. Removal from pasture, mixed grazing (cattle before sheep) and an albendazole slow release bolus all significantly (P < 0.05) reduced levels of infection in animals so treated, compared with control sheep which were treated periodically with anthelmintics as standard farm management practice. Removal of sheep from the pasture for 30 days in the summer seemed to have beneficial effects. Treatment of sheep weekly with albendazole increased levels of infection in the sheep over controls. The status of vaccination is described and the potential of intergenic competition in grazing management and perhaps vaccination is discussed. Resistance of nematodes to anthelmintics was relatively wide-spread. In both intensive and non-intensive systems. Oestrus ovis larvae were present in flock sheep for 10-12 months per year. Imagines failed to develop from 27 April-9 August and it was concluded that larvae had to overwinter in sheep to survive. Recommendations for integrated control are made for both intensive and non-intensive

  14. Patterns of inflammatory responses and parasite tolerance vary with malaria transmission intensity.

    PubMed

    Ademolue, Temitope W; Aniweh, Yaw; Kusi, Kwadwo A; Awandare, Gordon A

    2017-04-11

    In individuals living in malaria-endemic regions, parasitaemia thresholds for the onset of clinical symptoms vary with transmission intensity. The mechanisms that mediate this relationship are however, unclear. Since inflammatory responses to parasite infection contribute to the clinical manifestation of malaria, this study investigated inflammatory cytokine responses in children with malaria from areas of different transmission intensities (ranging from low to high). Blood samples were obtained from children confirmed with malaria at community hospitals in three areas with differing transmission intensities. Cytokine levels were assessed using the Luminex(®)-based magnetic bead array system, and levels were compared across sites using appropriate statistical tests. The relative contributions of age, gender, parasitaemia and transmission intensity on cytokine levels were investigated using multivariate regression analysis. Parasite density increased with increasing transmission intensity in children presenting to hospital with symptomatic malaria, indicating that the parasitaemia threshold for clinical malaria increases with increasing transmission intensity. Furthermore, levels of pro-inflammatory cytokines, including tumour necrosis factor alpha (TNF-α), interferon-gamma (IFN-γ), interleukin (IL)-1β, IL-2, IL-6, IL-8, and IL-12, decreased with increasing transmission intensity, and correlated significantly with parasitaemia levels in the low transmission area but not in high transmission areas. Similarly, levels of anti-inflammatory cytokines, including IL-4, IL-7, IL-10 and IL-13, decreased with increasing transmission intensity, with IL-10 showing strong correlation with parasitaemia levels in the low transmission area. Multiple linear regression analyses revealed that transmission intensity was a stronger predictor of cytokine levels than age, gender and parasitaemia. Taken together, the data demonstrate a strong relationship between the prevailing

  15. The anthropogenic environment lessens the intensity and prevalence of gastrointestinal parasites in Balinese long-tailed macaques (Macaca fascicularis).

    PubMed

    Lane, Kelly E; Holley, Concerta; Hollocher, Hope; Fuentes, Agustin

    2011-04-01

    The distribution of wildlife parasites in a landscape is intimately tied to the spatial distribution of hosts. In parasite species, including many gastrointestinal parasites, with obligate or common environmental life stages, the dynamics of the parasite can also be strongly affected by geophysical components of the environment. This is especially salient in host species, for example humans and macaques, which thrive across a wide variety of habitat types and quality and so are exposed to a wealth of environmentally resilient parasites. Here, we examine the effect of environmental and anthropogenic components of the landscape on the prevalence, intensity, and species diversity of gastrointestinal parasites across a metapopulation of long-tailed macaques on the island of Bali, Indonesia. Using principal-components analysis, we identified significant interaction effects between specific environmental and anthropogenic components of the landscape, parsing the Balinese landscape into anthropogenic (PC1), mixed environment (PC2), and non-anthropogenic (PC3) components. Further, we determined that the anthropogenic environment can mitigate the prevalence and intensity of specific gut parasites and the intensity of the overall community of gut parasites, but that non-anthropogenically driven landscape components have no significant effect in increasing or reducing the intensity or prevalence of the community of gut parasites in Balinese macaques.

  16. Animal health and greenhouse gas intensity: the paradox of periparturient parasitism.

    PubMed

    Houdijk, J G M; Tolkamp, B J; Rooke, J A; Hutchings, M R

    2017-09-01

    Here we provide the first known direct measurements of pathogen challenge impacts on greenhouse gas production, yield and intensity. Twin-rearing ewes were ad libitum fed pelleted lucerne from day -32 to 36 (day 0 is parturition), and repeatedly infected with 10,000 Teladorsagia circumcincta infective larvae (n=16), or sham-dosed with water (n=16). A third group of 16 ewes were fed at 80% of uninfected ewes' feed intake during lactation. Methane emissions were measured in respiration chambers (day 30-36) whilst total tract apparent nutrient digestibility around day 28 informed calculated manure methane and nitrous oxide emissions estimates. Periparturient parasitism reduced feed intake (-9%) and litter weight gain (-7%) and doubled maternal body weight loss. Parasitism reduced daily enteric methane production by 10%, did not affect the methane yield per unit of dry matter intake but increased the yield per unit of digestible organic matter intake by 14%. Parasitism did not affect the daily calculated manure methane and nitrous oxide production, but increased the manure methane and nitrous oxide yields per unit of dry matter intake by 16% and 4%, respectively, and per unit of digestible organic matter intake by 46% and 31%, respectively. Accounting for increased lucerne input for delayed weaning and maternal body weight loss compensation, parasitism increased the calculated greenhouse gas intensity per kg of lamb weight gain for enteric methane (+11%), manure methane (+32%) and nitrous oxide (+30%). Supplemented with the global warming potential associated with production of pelleted lucerne, we demonstrated that parasitism increased calculated global warming potential per kg of lamb weight gain by 16%, which was similar to the measured impact of parasitism on the feed conversion ratio. Thus, arising from a pathogen-induced feed efficiency reduction and modified greenhouse gas emissions, we demonstrated that ovine periparturient parasitism increases greenhouse gas

  17. Studies on gastrointestinal parasites of pigs in Shimoga region of Karnataka.

    PubMed

    Krishna Murthy, C M; Ananda, K J; Adeppa, J; Satheesha, M G

    2016-09-01

    The study was conducted to ascertain the actual status of gastro-intestinal parasites in pigs maintained under different rearing systems in Shimoga region, Karnataka state. A total of 150 Pigs fecal samples were examined, which includes 50 from organized piggery farm, Veterinary College Shimoga, 50 from private piggery farm of Shimoga and 50 from free range desi pigs of Shimoga city. The fecal samples were processed and examined by direct and sedimentation method. Out of 50 fecal samples examined from organized piggery farm, 19 were found positive for different parasitic eggs, Out of 50 fecal samples screened form private farm, 28 harbored different parasites, whereas from 50 free range desi pigs fecal samples examined, all showed one and other parasitic eggs/ova. The percent prevalence of parasitic infection is more in free range desi pigs compared to Yorkshire breeds maintained under stall fed condition.

  18. Neobenedenia melleni Parasite of Red Snapper, Lutjanus erythropterus, with Regression Statistical Analysis between Fish Length, Temperature, and Parasitic Intensity in Infected Fish, Cultured at Jerejak Island, Penang, Malaysia

    PubMed Central

    Ravi, Rajiv

    2016-01-01

    The fish parasites collected from Lutjanus erythropterus fish species showed a correlation with parasitic intensity, fish size, and temperature, and statistical model summary was produced using SPSS version 20, statistical software. Statistical model summary concluded that among the variables which significantly predict the prevalence of Neobenedenia melleni parasites are fish length and water temperature, both significant at 1% and 5%. Furthermore, the increase in one unit of fish length, holding other variables constant, increases the prevalence of parasite by approximately 1 (0.7≈1) unit. Also, increasing the temperature from 32°C to 33°C will positively increase the number of parasites by approximately 0.32 units, holding other variables constant. The model can be summarized as estimated number of Neobenedenia melleni parasites = 8.2 + 0.7 ⁎ (fish length) + 0.32 ⁎ (water temperature). Next, this study has also shown the DNA sequence and parasitic morphology of Neobenedenia melleni. Nucleotide sequence for 18s ribosomal gene RNA in this study showed 99% similarity with N. melleni EU707804.1 from GenBank. Finally, all the sequence of Neobenedenia melleni in this study was deposited in GenBank with accession numbers of KU843501, KU843502, KU843503, and KU843504. PMID:27190634

  19. Disruptions of Host Immunity and Inflammation by Giardia Duodenalis: Potential Consequences for Co-Infections in the Gastro-Intestinal Tract

    PubMed Central

    Cotton, James A.; Amat, Christina B.; Buret, Andre G.

    2015-01-01

    Giardia duodenalis (syn. G. intestinalis, or G. lamblia) is a leading cause of waterborne diarrheal disease that infects hundreds of millions of people annually. Research on Giardia has greatly expanded within the last few years, and our understanding of the pathophysiology and immunology on this parasite is ever increasing. At peak infection, Giardia trophozoites induce pathophysiological responses that culminate in the development of diarrheal disease. However, human data has suggested that the intestinal mucosa of Giardia-infected individuals is devoid of signs of overt intestinal inflammation, an observation that is reproduced in animal models. Thus, our understanding of host inflammatory responses to the parasite remain incompletely understood and human studies and experimental data have produced conflicting results. It is now also apparent that certain Giardia infections contain mechanisms capable of modulating their host’s immune responses. As the oral route of Giardia infection is shared with many other gastrointestinal (GI) pathogens, co-infections may often occur, especially in places with poor sanitation and/or improper treatment of drinking water. Moreover, Giardia infections may modulate host immune responses and have been found to protect against the development of diarrheal disease in developing countries. The following review summarizes our current understanding of the immunomodulatory mechanisms of Giardia infections and their consequences for the host, and highlights areas for future research. Potential implications of these immunomodulatory effects during GI co-infection are also discussed. PMID:26569316

  20. Sexual comparisons in immune ability, survival and parasite intensity in two damselfly species.

    PubMed

    Córdoba-Aguilar, A; Contreras-Garduño, J; Peralta-Vázquez, H; Luna-González, A; Campa-Córdova, A I; Ascencio, F

    2006-08-01

    Recent evolutionary studies have suggested that females have a more robust immune system than males. Using two damselfly species (Hetaerina americana and Argia tezpi), we tested if females produced higher immune responses (as phenoloxidase and hydrolytic enzymes), had a higher survival (using a nylon implant inserted in the abdomen and measuring survival after 24h) and fewer parasites (gregarines and water mites) than males. We also tested whether immune differences should emerge in different body areas (thorax vs. abdomen) within each sex with the prediction that only females will differ with the abdomen having a higher immune response than their thorax since the former area, for ecological and physiological reasons, may be a target zone for increased immune investment. Animals were adults of approximately the same age. In both species, females were more immunocompetent than males, but only in H. americana females were immune responses greater in the abdomen than in the thorax. However, there were no differences in survival and parasite intensity or the probability of being parasitised between the sexes in either of the two species. Thus, this study lends partial support to the principle that females are better at defending than males despite the null difference in parasitism and survival.

  1. Recent advances in molecular biology of parasitic viruses.

    PubMed

    Banik, Gouri Rani; Stark, Damien; Rashid, Harunor; Ellis, John T

    2014-01-01

    The numerous protozoa that can inhabit the human gastro-intestinal tract are known, yet little is understood of the viruses which infect these protozoa. The discovery, morphologic details, purification methods of virus-like particles, genome and proteome of the parasitic viruses, Entamoeba histolytica, Giardia lamblia, Trichomonas vaginalis, and the Eimeria sp. are described in this review. The protozoan viruses share many common features: most of them are RNA or double-stranded RNA viruses, ranging between 5 and 8 kilobases, and are spherical or icosahedral in shape with an average diameter of 30-40 nm. These viruses may influence the function and pathogenicity of the protozoa which they infect, and may be important to investigate from a clinical perspective. The viruses may be used as specific genetic transfection vectors for the parasites and may represent a research tool. This review provides an overview on recent advances in the field of protozoan viruses.

  2. Improving the efficiency of feed utilization in poultry by selection. 2. Genetic parameters of excretion traits and correlations with anatomy of the gastro-intestinal tract and digestive efficiency

    PubMed Central

    2011-01-01

    Background Poultry production has been widely criticized for its negative environmental impact related to the quantity of manure produced and to its nitrogen and phosphorus content. In this study, we investigated which traits related to excretion could be used to select chickens for lower environmental pollution. The genetic parameters of several excretion traits were estimated on 630 chickens originating from 2 chicken lines divergently selected on apparent metabolisable energy corrected for zero nitrogen (AMEn) at constant body weight. The quantity of excreta relative to feed consumption (CDUDM), the nitrogen and phosphorus excreted, the nitrogen to phosphorus ratio and the water content of excreta were measured, and the consequences of such selection on performance and gastro-intestinal tract (GIT) characteristics estimated. The genetic correlations between excretion, GIT and performance traits were established. Results Heritability estimates were high for CDUDM and the nitrogen excretion rate (0.30 and 0.29, respectively). The other excretion measurements showed low to moderate heritability estimates, ranging from 0.10 for excreta water content to 0.22 for the phosphorus excretion rate. Except for the excreta water content, the CDUDM was highly correlated with the excretion traits, ranging from -0.64 to -1.00. The genetic correlations between AMEn or CDUDM and the GIT characteristics were very similar and showed that a decrease in chicken excretion involves an increase in weight of the upper part of the GIT, and a decrease in the weight of the small intestine. Conclusion In order to limit the environmental impact of chicken production, AMEn and CDUDM seem to be more suitable criteria to include in selection schemes than feed efficiency traits. PMID:21846409

  3. Improving the efficiency of feed utilization in poultry by selection. 2. Genetic parameters of excretion traits and correlations with anatomy of the gastro-intestinal tract and digestive efficiency.

    PubMed

    de Verdal, Hugues; Narcy, Agnès; Bastianelli, Denis; Chapuis, Hervé; Même, Nathalie; Urvoix, Séverine; Le Bihan-Duval, Elisabeth; Mignon-Grasteau, Sandrine

    2011-08-17

    Poultry production has been widely criticized for its negative environmental impact related to the quantity of manure produced and to its nitrogen and phosphorus content. In this study, we investigated which traits related to excretion could be used to select chickens for lower environmental pollution.The genetic parameters of several excretion traits were estimated on 630 chickens originating from 2 chicken lines divergently selected on apparent metabolisable energy corrected for zero nitrogen (AMEn) at constant body weight. The quantity of excreta relative to feed consumption (CDUDM), the nitrogen and phosphorus excreted, the nitrogen to phosphorus ratio and the water content of excreta were measured, and the consequences of such selection on performance and gastro-intestinal tract (GIT) characteristics estimated. The genetic correlations between excretion, GIT and performance traits were established. Heritability estimates were high for CDUDM and the nitrogen excretion rate (0.30 and 0.29, respectively). The other excretion measurements showed low to moderate heritability estimates, ranging from 0.10 for excreta water content to 0.22 for the phosphorus excretion rate. Except for the excreta water content, the CDUDM was highly correlated with the excretion traits, ranging from -0.64 to -1.00. The genetic correlations between AMEn or CDUDM and the GIT characteristics were very similar and showed that a decrease in chicken excretion involves an increase in weight of the upper part of the GIT, and a decrease in the weight of the small intestine. In order to limit the environmental impact of chicken production, AMEn and CDUDM seem to be more suitable criteria to include in selection schemes than feed efficiency traits.

  4. New species of Spauligodon Skrjabin, Schikhobalova & Lagodovskaja, 1960 and Thubunea Seurat, 1914 (Nematoda) from the gastro-intestinal tract of lizards in Iran.

    PubMed

    Pazoki, Samaneh; Rahimian, Hassan

    2014-11-01

    As part of a faunistic study on helminth parasites of Iranian lizards collected from localities in the north of Isfahan province in Iran, two new nematode species belonging to two different families, Pharyngodonidae Travassos, 1919 and Physalopteroidae Railliet, 1893, were found and are, hereby, described. Spauligodon persiensis n. sp. from the large intestine of Cyrtopodion scabrum Heyden is characterised by its imperceptible lateral alae, lack of spicule, different shape of the genital curtain, position of last pair of papillae, aspinose tail in males, position of the vulva and excretory pore, and a tail filament with six to nine spines in females. Thubunea mobedii n. sp. from the stomach of Laudakia nupta nupta (De Filipi) differs from the other species in the genus by possessing a vulva at level of the posterior portion of the oesophageal-intestinal junction in females, lacking spicules, and having a different number of papillae in males. The present paper provides the results of detailed morphological examination of the two new nematode species, using both light and scanning electron microscopy. Taxonomically important characteristics for the members of the two nematode genera, Spauligodon Skrjabin, Schikhobalova & Lagodovskaja, 1960 and Thubunea Seurat, 1914, are also reviewed.

  5. Parasitic slow extraction of extremely weak beam from a high-intensity proton rapid cycling synchrotron

    NASA Astrophysics Data System (ADS)

    Zou, Ye; Tang, Jingyu; Yang, Zheng; Jing, Hantao

    2014-02-01

    This paper proposes a novel method to extract extremely weak beam from a high-intensity proton rapid cycling synchrotron (RCS) in the parasitic mode, while maintaining the normal fast extraction. The usual slow extraction method from a synchrotron by employing third-order resonance cannot be applied in a high-intensity RCS due to a very short flat-top at the extraction energy and the strict control on beam loss. The proposed parasitic slow extraction method moves the beam to scrape a scattering foil prior to the fast beam extraction by employing either a local orbit bump or momentum deviation or their combination, so that the halo part of the beam will be scattered. A part of the scattered particles will be extracted from the RCS and guided to the experimental area. The slow extraction process can last about a few milliseconds before the beam is extracted by the fast extraction system. The method has been applied to the RCS of China Spallation Neutron Source. With 1.6 GeV in the extraction energy, 62.5 μA in the average current and 25 Hz in the repetition rate for the RCS, the proton intensity by the slow extraction method can be up to 2×104 protons per cycle or 5×105 protons per second. The extracted beam has also a good time structure of approximately uniform in a spill which is required for many applications such as detector tests. Detailed studies including the scattering effect in the foil, the local orbit bump by the bump magnets and dispersive orbit bump by modifying the RF pattern, the multi-particle simulations by ORBIT and TURTLE codes, and some technical features for the extraction magnets are presented.

  6. The effect of birdsfoot trefoil (Lotus corniculatus) and chicory (Cichorium intybus) on parasite intensities and performance of lambs naturally infected with helminth parasites.

    PubMed

    Marley, C L; Cook, R; Keatinge, R; Barrett, J; Lampkin, N H

    2003-02-28

    Conventionally, farmers rely upon the routine use of anthelmintics to control helminth parasites and their use has proved highly cost-effective. However, several factors, including the emergence of helminths resistant to pharmaceutical anthelmintics, are forcing farmers to seek alternative approaches to parasite control. Studies in New Zealand have shown that some alternative forages may reduce parasitic infestation in sheep. In the current study, it was found that under UK environmental conditions lambs with naturally acquired helminth infections grazing chicory (Cichorium intybus) and birdsfoot trefoil (Lotus corniculatus) had fewer helminth parasites than sheep grazing ryegrass/white clover (Lolium perenne/Trifolium repens). Twelve pure-bred Lleyn male lambs grazed replicated 0.5ha plots of birdsfoot trefoil, chicory or ryegrass/white clover for 5 weeks. Liveweight and faecal egg counts (FECs) were determined weekly and eight lambs per forage were slaughtered at the end of the trial to determine total helminth intensities. Lambs grazing birdsfoot trefoil had a lower FEC on day 7 (P<0.05) and fewer total adult helminths than those grazing the other forages on day 35 (P<0.01). Lambs grazing chicory did not have significantly lower FEC than lambs grazing other forages but these lambs were found to have fewer total adult abomasal helminths than lambs grazing ryegrass/white clover (P<0.001). As the performance of grazing lambs is inversely correlated with the intensity of helminth parasites, these alternative forages could be used to improve the liveweight gain of lambs produced in the UK. Overall, the results support the contention that alternative forages could have a positive role in the control of helminth parasites in sheep, subject to successful agronomic development and integration of these forages into whole farm systems.

  7. Opportunistic parasitic infections among immunocompromised Egyptian patients.

    PubMed

    Baiomy, Ahmed M Said; Mohamed, Khairy Abd Al-Hamid; Ghannam, Mohamed A Mosaad; Shahat, Samir Abd Al-Razek; Al-Saadawy, Ahmed Saad Kamel

    2010-12-01

    The commonest opportunistic parasites causing morbidity and/or mortality in the immuno-compromised subjects are mainly the gastro-intestinal ones. This study clarified the prevalence of the opportunistic parasites among a group of immunocompromised patients selected from Al Azhar University Hospitals. One hundred immunocompromised patients (GI) were divided into GIa: 40 malignancy patients. GIb: 30 with diabetes mellitus. GIc: 30 with chronic renal failure. GII: included 20 cross-matched healthy subjects as controls. Sheets were filled out on each subject including all personal and medical history. Both groups were subjected to stool and blood examinations for parasites. The results showed opportunistic parasites in 30% of patients and in 10% of healthy controls. The highest group had parasitosis was patients suffering from malignancy (18%). The patients suffering from chronic renal failure or from diabetes mellitus were equally affected (6% each group). There was significant relation between malignant patients and diabetic or chronic renal failure ones, but without significant relation between diabetic and chronic renal failure patients. Giardia lamblia was the most common parasite found in the patients (10%) of which 5% were among patients suffering from malignancy. Others were Cryptospotidium parvum (7%) Cyclospora cayetanensis (3%) and Microsporidia species (2%). Mixed infection was detected in 2 cases that had C. parvum and Cyclospora. But, neither Isospora belli nor Strongyloides stercoralis were detected. Also, ELISA showed antibodies against Toxoplasma gondii in sex patients but none against Leishmania d. infantum.

  8. Intensity of parasitic mite infection decreases with hibernation duration of the host snail.

    PubMed

    Haeussler, E M; Pizá, J; Schmera, D; Baur, B

    2012-07-01

    Temperature can be a limiting factor on parasite development. Riccardoella limacum, a haematophagous mite, lives in the mantle cavity of helicid land snails. The prevalence of infection by R. limacum in populations of the land snail Arianta arbustorum is highly variable (0-78%) in Switzerland. However, parasitic mites do not occur in host populations at altitudes of 1290 m or higher. It has been hypothesized that the host's hibernation period might be too long at high elevations for mites and their eggs to survive. To test this hypothesis, we experimentally infected snails and allowed them to hibernate at 4°C for periods of 4-7 months. Winter survival of host snails was negatively affected by R. limacum. The intensity of mite infection decreased with increasing hibernation duration. Another experiment with shorter recording intervals revealed that mites do not leave the host when it buries in the soil at the beginning of hibernation. The number of mites decreased after 24 days of hibernation, whereas the number of eggs attached to the lung tissue remained constant throughout hibernation. Thus, R. limacum survives the winter in the egg stage in the host. Low temperature at high altitudes may limit the occurrence of R. limacum.

  9. Parasitic infections of the grey-breasted helmet guinea-fowl (Numida meleagris galeata) in Nigeria.

    PubMed

    Ayeni, J S; Dipeolu, O O; Okaeme, A N

    1983-02-01

    The major helminth parasites found in wild, semi-wild and golden Sovereign stock guinea fowl were Heterakis gallinarum, Ascaridia galli, Capillaria caudinflata, Raillietina tetragona and R. echinobothrida, while Eimeria species was the most important gastro-intestinal protozoan parasite. The incidence of the latter was higher in the semi-wild stock than in the wild stock. Necropsy of dead guinea-fowl indicated that A. galli, H. gallinarum and Eimeria species were indeed responsible for their deaths, especially in the young birds. Parasites found in blood smears were Leucocytozoon sp., Plasmodium sp. and Aegyptianella pullorum. The only tick found, Argas persicus, was on a few semi-wild stock, while lice of genus Damalinia were found only on wild birds.

  10. Blood parasites of two Costa Rican amphibians with comments on detection and microfilaria density associated with adult filarial worm intensity.

    PubMed

    McKenzie, Valerie J; Starks, Hilary A

    2008-08-01

    The 2 objectives of this study were: (1) to compare parasite detectability in blood smears obtained from toe-clips versus the heart from amphibian hosts; and (2) to test whether microfilariae density is correlated with adult filarial worm intensity. We examined blood parasites of 2 species of amphibians, Rana vaillanti (n = 45) and Eleutherodactylus fitzingeri (n = 36), from Costa Rica collected during the summer of 2003. Separate blood smears were obtained from toe-clips and the heart during necrospy. Eight species of blood parasites were identified from R. vaillanti and 1 from E. fitzingeri. Each parasite species was counted in a 2 x 2.2-cm2 area on each blood smear, and the density of host red blood cells (RBCs) was estimated using a sub-sampling approach, allowing parasite infections to be expressed as individuals per RBC. The detection failure rate for toe-cut smears ranged from 71-100% (x = 92.3%) and from 0-9% (x = 2.4%) for heart smears, depending on parasite species. The density of RBCs was significantly higher in smears produced from heart samples and may explain the differences in detectability. Foleyellides striatus microfilariae densities (per RBC) were significantly correlated with adult female worm intensity (R2 = 0.32, P = 0.011).

  11. Prevalence and epidemiologic characteristics of opportunistic and non-opportunistic intestinal parasitic infections in HIV positive patients in Manipur.

    PubMed

    Anand, L; Dhanachand, C; Brajachand, N

    1998-03-01

    A survey of the intestinal parasites among the HIV positive asymptomatic injecting drug users (IDUs) in Manipur State in North-east India revealed the presence of three protozoan and two nematode species. Of these, the two opportunistic parasitic protozoans i.e., Cryptosporidium sp. (94.4 percent) and Isospora sp. (10.7 percent) were predominant over Entamoeba histolytica (5.6 percent), while non-opportunistic parasitic nematodes, i.e. Ascaris lumbricoides (4.6 percent) and Ancylostoma sp. (1 percent) were the less frequently detected ones. In all cases, the fungal flora were predominant. Candida sp. was more often encountered compared to Cladosporium and Humicloa. The study also revealed that although these individuals showed no gastro-intestinal disorders like diarrhoea, they still harbour these opportunistic and non-opportunistic parasites and act as carriers, particularly of the former category, in the community via contaminated water and open defaecation practices.

  12. Infection Intensity-Dependent Responses of Anopheles gambiae to the African Malaria Parasite Plasmodium falciparum ▿ †

    PubMed Central

    Mendes, Antonio M.; Awono-Ambene, Parfait H.; Nsango, Sandrine E.; Cohuet, Anna; Fontenille, Didier; Kafatos, Fotis C.; Christophides, George K.; Morlais, Isabelle; Vlachou, Dina

    2011-01-01

    Malaria remains a devastating disease despite efforts at control and prevention. Extensive studies using mostly rodent infection models reveal that successful Plasmodium parasite transmission by the African mosquito vector Anopheles gambiae depends on finely tuned vector-parasite interactions. Here we investigate the transcriptional response of A. gambiae to geographically related Plasmodium falciparum populations at various infection intensities and different infection stages. These responses are compared with those of mosquitoes infected with the rodent parasite Plasmodium berghei. We demonstrate that mosquito responses are largely dependent on the intensity of infection. A major transcriptional suppression of genes involved in the regulation of midgut homeostasis is detected in low-intensity P. falciparum infections, the most common type of infection in Africa. Importantly, genes transcriptionally induced during these infections tend to be phylogenetically unique to A. gambiae. These data suggest that coadaptation between vectors and parasites may act to minimize the impact of infection on mosquito fitness by selectively suppressing specific functional classes of genes. RNA interference (RNAi)-mediated gene silencing provides initial evidence for important roles of the mosquito G protein-coupled receptors (GPCRs) in controlling infection intensity-dependent antiparasitic responses. PMID:21844236

  13. MHC-I affects infection intensity but not infection status with a frequent avian malaria parasite in blue tits.

    PubMed

    Westerdahl, Helena; Stjernman, Martin; Råberg, Lars; Lannefors, Mimi; Nilsson, Jan-Åke

    2013-01-01

    Host resistance against parasites depends on three aspects: the ability to prevent, control and clear infections. In vertebrates the immune system consists of innate and adaptive immunity. Innate immunity is particularly important for preventing infection and eradicating established infections at an early stage while adaptive immunity is slow, but powerful, and essential for controlling infection intensities and eventually clearing infections. Major Histocompatibility Complex (MHC) molecules are central in adaptive immunity, and studies on parasite resistance and MHC in wild animals have found effects on both infection intensity (parasite load) and infection status (infected or not). It seems MHC can affect both the ability to control infection intensities and the ability to clear infections. However, these two aspects have rarely been considered simultaneously, and their relative importance in natural populations is therefore unclear. Here we investigate if MHC class I genotype affects infection intensity and infection status with a frequent avian malaria infection Haemoproteus majoris in a natural population of blue tits Cyanistes caeruleus. We found a significant negative association between a single MHC allele and infection intensity but no association with infection status. Blue tits that carry a specific MHC allele seem able to suppress H. majoris infection intensity, while we have no evidence that this allele also has an effect on clearance of the H. majoris infection, a result that is in contrast with some previous studies of MHC and avian malaria. A likely explanation could be that the clearance rate of avian malaria parasites differs between avian malaria lineages and/or between avian hosts.

  14. An Overview of Trypanosoma brucei Infections: An Intense Host–Parasite Interaction

    PubMed Central

    Ponte-Sucre, Alicia

    2016-01-01

    Trypanosoma brucei rhodesiense and T. brucei gambiense, the causative agents of Human African Trypanosomiasis, are transmitted by tsetse flies. Within the vector, the parasite undergoes through transformations that prepares it to infect the human host. Sequentially these developmental stages are the replicative procyclic (in which the parasite surface is covered by procyclins) and trypo-epimastigote forms, as well as the non-replicative, infective, metacyclic form that develops in the vector salivary glands. As a pre-adaptation to their life in humans, metacyclic parasites begin to express and be densely covered by the Variant Surface Glycoprotein (VSG). Once the metacyclic form invades the human host the parasite develops into the bloodstream form. Herein the VSG triggers a humoral immune response. To avoid this humoral response, and essential for survival while in the bloodstream, the parasite changes its cover periodically and sheds into the surroundings the expressed VSG, thus evading the consequences of the immune system activation. Additionally, tools comparable to quorum sensing are used by the parasite for the successful parasite transmission from human to insect. On the other hand, the human host promotes clearance of the parasite triggering innate and adaptive immune responses and stimulating cytokine and chemokine secretion. All in all, the host–parasite interaction is extremely active and leads to responses that need multiple control sites to develop appropriately. PMID:28082973

  15. Estimation of infection of internal parasites in horses from different type of farms.

    PubMed

    Sokół, Rajmund; Raś-Noryńska, Małgorzata; Michalczyk, Maria; Raś, Andrzej; Rapacz-Leonard, Anna; Koziatek, Sylwia

    2015-01-01

    Studies were carried out in year 2014 during the pasture period (from April to October) in Warmia and Mazury Region. Fecal samples were taken from cold- and warmblood horses from individual and agrotouristic farms with the different housing, feeding and pasture- care practices. Total of 512 horses were examined (320 mares, 170 geldings and 22 stallions). In the group of 185 horses from individual farms, 119 animals (64.3%) were infected with gastro-intestinal parasites. Among the 372 horses from agrotouristic farms 169 (51.7%) were infected with parasites. Most of the animals expelled the eggs of Cyathostominae. In some individuals occurred eggs of Strongylus spp., Parascaris equorum, Strongyloides westeri and tapeworm of Anoplocephala. The number of infected horses from agrotouristic farms was lower than from individual farms, probably due to more regular deworming (usually 2 times a year) and bigger care paid to cleaning pastures.

  16. Application of a Multiplex Quantitative PCR to Assess Prevalence and Intensity Of Intestinal Parasite Infections in a Controlled Clinical Trial

    PubMed Central

    Llewellyn, Stacey; Inpankaew, Tawin; Nery, Susana Vaz; Gray, Darren J.; Verweij, Jaco J.; Clements, Archie C. A.; Gomes, Santina J.; Traub, Rebecca; McCarthy, James S.

    2016-01-01

    Background Accurate quantitative assessment of infection with soil transmitted helminths and protozoa is key to the interpretation of epidemiologic studies of these parasites, as well as for monitoring large scale treatment efficacy and effectiveness studies. As morbidity and transmission of helminth infections are directly related to both the prevalence and intensity of infection, there is particular need for improved techniques for assessment of infection intensity for both purposes. The current study aimed to evaluate two multiplex PCR assays to determine prevalence and intensity of intestinal parasite infections, and compare them to standard microscopy. Methodology/Principal Findings Faecal samples were collected from a total of 680 people, originating from rural communities in Timor-Leste (467 samples) and Cambodia (213 samples). DNA was extracted from stool samples and subject to two multiplex real-time PCR reactions the first targeting: Necator americanus, Ancylostoma spp., Ascaris spp., and Trichuris trichiura; and the second Entamoeba histolytica, Cryptosporidium spp., Giardia. duodenalis, and Strongyloides stercoralis. Samples were also subject to sodium nitrate flotation for identification and quantification of STH eggs, and zinc sulphate centrifugal flotation for detection of protozoan parasites. Higher parasite prevalence was detected by multiplex PCR (hookworms 2.9 times higher, Ascaris 1.2, Giardia 1.6, along with superior polyparasitism detection with this effect magnified as the number of parasites present increased (one: 40.2% vs. 38.1%, two: 30.9% vs. 12.9%, three: 7.6% vs. 0.4%, four: 0.4% vs. 0%). Although, all STH positive samples were low intensity infections by microscopy as defined by WHO guidelines the DNA-load detected by multiplex PCR suggested higher intensity infections. Conclusions/Significance Multiplex PCR, in addition to superior sensitivity, enabled more accurate determination of infection intensity for Ascaris, hookworms and

  17. Inter-annual variation in prevalence and intensity of mite parasitism relates to appearance and expression of damselfly resistance

    PubMed Central

    2010-01-01

    Background Insects can resist parasites using the costly process of melanotic encapsulation. This form of physiological resistance has been studied under laboratory conditions, but the abiotic and biotic factors affecting resistance in natural insect populations are not well understood. Mite parasitism of damselflies was studied in a temperate damselfly population over seven seasons to determine if melanotic encapsulation of mite feeding tubes was related to degree of parasitism, host sex, host size, emergence timing, duration of the emergence period, and average daily air temperature. Results Although parasite prevalence in newly emerged damselflies was > 77% each year, hosts did not resist mites in the early years of study. Resistance began the year that there was a dramatic increase in the number of mites on newly emerged damselflies. Resistance continued to be correlated with mite prevalence and intensity throughout the seven-year study. However, the percentage of hosts resisting only ranged from 0-13% among years and resistance was not sex-biased and was not correlated with host size. Resistance also was not correlated with air temperature or with timing or duration of damselfly emergence. Conclusions Resistance in host damselflies was weakly and variably expressed over the study period. Factors such as temperature, which have been identified in laboratory studies as contributing to resistance by similar hosts, can be irrelevant in natural populations. This lack of temperature effect may be due to the narrow range in temperatures observed at host emergence among years. Degree of mite parasitism predicted both the appearance and continued expression of resistance among parasitized damselflies. PMID:20152057

  18. Metazoan parasites from odontocetes off New Zealand: new records.

    PubMed

    Lehnert, Kristina; Randhawa, Haseeb; Poulin, Robert

    2017-08-10

    Information about the parasite fauna of spectacled porpoises and cetaceans from New Zealand waters in general is scarce. This study takes advantage of material archived in collections of the Otago Museum in Dunedin and Massey University in Auckland, sampled from cetacean species found stranded along the New Zealand coastline between 2007 and 2014. Parasites from seven species of cetaceans (spectacled porpoise, Phocoena dioptrica (n = 2 individuals examined); pygmy sperm whale (n = 1); long-finned pilot whale, Globicephala melas (n = 1); Risso's dolphin, Grampus griseus (n = 1); short-beaked common dolphin, Delphinus delphis (n = 7); striped dolphin, Stenella coeruleoalba (n = 3) and dusky dolphin, Lagenorhynchus obscurus (n = 2)) from the respiratory and gastro-intestinal tract, cranial sinus, liver, urogenital and mammary tract, fascia and blubber were investigated. Ten parasite species were identified, belonging to the Nematoda (Stenurus minor, Stenurus globicephalae, Halocercus sp. (Pseudaliidae), Anisakis sp. (Anisakidae), Crassicauda sp. (Crassicaudidae)), Cestoda (Phyllobothrium delphini and Monorygma grimaldii (Phyllobothriidae)), Trematoda (Brachicladium palliata and Brachicladium delphini (Brachicladiidae)) and Crustacea (Scutocyamus antipodensis (Cyamidae)). Some of the parasite species encountered comprises new records for their host. Although the material was not sampled within a systematic parasitological survey, the findings contain valuable new information about the parasite fauna of rare, vagile and vulnerable marine wildlife from a remote oceanic environment.

  19. Population density and phenotypic attributes influence the level of nematode parasitism in roe deer.

    PubMed

    Body, Guillaume; Ferté, Hubert; Gaillard, Jean-Michel; Delorme, Daniel; Klein, François; Gilot-Fromont, Emmanuelle

    2011-11-01

    The impact of parasites on population dynamics is well documented, but less is known on how host population density affects parasite spread. This relationship is difficult to assess because of confounding effects of social structure, population density, and environmental conditions that lead to biased among-population comparisons. Here, we analyzed the infestation by two groups of nematodes (gastro-intestinal (GI) strongyles and Trichuris) in the roe deer (Capreolus capreolus) population of Trois Fontaines (France) between 1997 and 2007. During this period, we experimentally manipulated population density through changes in removals. Using measures collected on 297 individuals, we quantified the impact of density on parasite spread after taking into account possible influences of date, age, sex, body mass, and weather conditions. The prevalence and abundance of eggs of both parasites in females were positively related to roe deer density, except Trichuris in adult females. We also found a negative relationship between parasitism and body mass, and strong age and sex-dependent patterns of parasitism. Prime-age adults were less often parasitized and had lower fecal egg counts than fawns or old individuals, and males were more heavily and more often infected than females. Trichuris parasites were not affected by weather, whereas GI strongyles were less present after dry and hot summers. In the range of observed densities, the observed effect of density likely involves a variation of the exposure rate, as opposed to variation in host susceptibility.

  20. Disease transmission in an extreme environment: nematode parasites infect reindeer during the Arctic winter.

    PubMed

    Carlsson, Anja M; Justin Irvine, R; Wilson, Kenneth; Piertney, Stuart B; Halvorsen, Odd; Coulson, Stephen J; Stien, Audun; Albon, Steve D

    2012-07-01

    Parasitic nematodes are found in almost all wild vertebrate populations but few studies have investigated these host-parasite relationships in the wild. For parasites with free-living stages, the external environment has a major influence on life-history traits, and development and survival is generally low at sub-zero temperatures. For reindeer that inhabit the high Arctic archipelago of Svalbard, parasite transmission is expected to occur in the summer, due to the extreme environmental conditions and the reduced food intake by the host in winter. Here we show experimentally that, contrary to most parasitic nematodes, Marshallagia marshalli of Svalbard reindeer is transmitted during the Arctic winter. Winter transmission was demonstrated by removing parasites in the autumn, using a novel delayed-release anthelmintic bolus, and estimating re-infection rates in reindeer sampled in October, February and April. Larval stages of nematodes were identified using molecular tools, whereas adult stages were identified using microscopy. The abundance of M. marshalli adult worms and L4s increased significantly from October to April, indicating that reindeer were being infected with L3s from the pasture throughout the winter. To our knowledge, this study is the first to experimentally demonstrate over-winter transmission of a gastro-intestinal nematode parasite in a wild animal. Potential mechanisms associated with this unusual transmission strategy are discussed in light of our knowledge of the life-history traits of this parasite.

  1. Parasite species richness and intensity of interspecific interactions increase with latitude in two wide-ranging hosts.

    PubMed

    Torchin, Mark E; Miura, Osamu; Hechinger, Ryan F

    2015-11-01

    Although the latitudinal diversity gradient is a well-known and general pattern, the mechanisms structuring it remain elusive. Two key issues limit differentiating these. First, habitat type usually varies with latitude, precluding a standardized evaluation of species richness. Second, broad-scale and local factors hypothesized to shape diversity patterns covary with one another, making it difficult to tease apart independent effects. Examining communities of parasites in widely distributed hosts can eliminate some of these confounding factors. We quantified diversity and interspecific interactions for trematode parasites infecting two similar snail species across 27 degrees of latitude from 43 locations in tropical and temperate oceans. Counter to typical patterns, we found that species richness, levels of parasitism, and intensity of intraguild predation increased with latitude. Because speciation rates are precluded from driving diversity gradients in this particular system, the reversed gradients are likely due to local ecological factors, specifically, increased productivity and stability. We highlight how this system may serve as a useful tool to provide insight into what processes drive diversity gradients in general.

  2. The effect of foraging and ontogeny on the prevalence and intensity of the invasive parasite Anguillicola crassus in the European eel Anguilla anguilla.

    PubMed

    Barry, J; Newton, M; Dodd, J A; Evans, D; Newton, J; Adams, C E

    2017-01-13

    Infection patterns of the invasive Anguillicola crassus nematode were investigated in a population of the European eel Anguilla anguilla where parasite invasion is very recent, Loch Lomond, Scotland. Intensity levels of the parasite were associated with differences in fish ontogeny and trophic ecology. Although eels foraged on both fish and invertebrates, individuals which were smaller and fed on invertebrates (>70% contribution to diet) were found to contain a greater number of swim bladder parasites compared to larger eel with a predominance of fish (>60% contribution) in their diet. Within affected fish, a significant negative relationship was found between fish length and parasite intensity, with smaller individuals having higher parasite intensity than larger individuals. This study indicates that food intake and infection risk are linked in this recently infected host-parasite system. From a management perspective increasing our understanding of how infection intensity and repeated exposure is linked to resource use in an ecosystem is important for the future management of this endangered species in Europe.

  3. Early cytokine responses during intestinal parasitic infections.

    PubMed Central

    Ishikawa, N; Goyal, P K; Mahida, Y R; Li, K F; Wakelin, D

    1998-01-01

    Infections with gastro-intestinal nematodes elicit immune and inflammatory responses mediated by cytokines released from T-helper type-2 (Th2) cells. In vitro assays of cells from the mesenteric lymph nodes (MLN) of experimentally infected rodents confirm that, after about 1 week, the dominant cytokine responses to mitogens and antigens are those associated with this Th-cell subset. Polarization of the Th response in this way implies an initial local cytokine environment that favours Th2 development. However, experimental infections with Trichinella spiralis and Nippostrongylus brasiliensis show that, within 2 days of worms reaching the intestine, MLN cells (MLNC) respond with a Th1 rather than a Th2 response [i.e. there is an increase in mRNA for the type 1 cytokine interferon-gamma (IFN-gamma), and mitogen-stimulated MLNC release IFN-gamma rather than interleukin-5 (IL-5)]. Antigen stimulation at this time does not elicit IFN-gamma release and the MLNC cannot adoptively transfer immunity. Within a few days the MLNC phenotype changes. There is a Th2 response (IL-5 release) to both mitogen and antigen stimulation and MLNC can adoptively transfer immunity. Early release of IFN-gamma is T-cell dependent, with CD4+ T cells playing the major role. The data are discussed in relation to factors regulating the mucosal response to invasion by parasites. PMID:9616376

  4. Decreased Intensity of Inflammation in Benznidazole-Treated Mice Inoculated with Trypanosoma cruzi I Stocks from Mexico and Persistence of Circulating Parasites

    PubMed Central

    Cruz-Zetina, Guillermo; del Rio-Rodriguez, Rodolfo; Ramos-Ligonio, Angel; López, Ruth; Monteon, Victor

    2012-01-01

    We analyzed the intensity of inflammation and parasitism in BALB/c mice infected with Trypanosoma cruzi I stocks from Mexico with and without benznidazole treatment in the acute phase of disease. Heart and skeletal muscles were evaluated for parasites and inflammation and blood was evaluated for persistence of circulating parasites. Parasitemia was influenced by T. cruzi stocks used and benznidazole treatment. This treatment cleared circulating parasites three days after starting treatment when monitored by direct microscopy. There was a significant reduction of inflammation in skeletal muscles after benznidazole treatment in animals infected with Mexican T. cruzi I stocks (P < 0.05), but this reduction was not significant in the heart (P > 0.05). Trypanosoma cruzi I parasites from Mexico were demonstrated by polymerase chain reaction in tissues and blood of animals after benznidazole treatment. PMID:22890036

  5. Temporal changes in distribution, prevalence and intensity of northern fowl mite (Ornithonyssus sylviarum) parasitism in commercial caged laying hens, with a comprehensive economic analysis of parasite impact.

    PubMed

    Mullens, Bradley A; Owen, Jeb P; Kuney, Douglas R; Szijj, Coralie E; Klingler, Kimberly A

    2009-03-09

    Establishment and spread of Ornithonyssus sylviarum were documented through time on sentinel hens (50 per house of 28,000-30,000 hens) in the first egg production cycle of three large commercial flocks (12 houses) of white leghorn hens. Mites were controlled using acaricide, and the impacts of treatment on mite populations and economic performance were documented. Mite prevalence and intensity increased rapidly and in tandem for 4-8 weeks after infestation. Intensity declined due to immune system involvement, but prevalence remained high, and this would affect mite sampling plan use and development. Early treatment was more effective at controlling mites; 85% of light infestations were eliminated by a pesticide spray (Ravap), versus 24% of heavy infestations. Hens infested later developed lower peak mite intensities, and those mite populations declined more quickly than on hens infested earlier in life. Raw spatial association by distance indices (SADIE), incorporating both the intensity and distribution of mites within a house, were high from week-to-week within a hen house. Once adjusted spatially to reflect variable hen cohorts becoming infested asynchronously, this analysis showed the association index tended to rebound at intervals of 5-6 weeks after the hen immune system first suppressed them. Large, consistent mite differences in one flock (high vs. low infestation levels) showed the economic damage of mite parasitism (assessed by flock indexing) was very high in the initial stages of mite expansion. Unmitigated infestations overall reduced egg production (2.1-4.0%), individual egg weights (0.5-2.2%), and feed conversion efficiency (5.7%), causing a profit reduction of $0.07-0.10 per hen for a 10-week period. Asynchronous infestation patterns among pesticide-treated hens may have contributed to a lack of apparent flock-level economic effects later in the production cycle. Individual egg weights differed with mite loads periodically, but could be either

  6. ENDOHELMINTHS IN BIRD HOSTS FROM NORTHERN CALIFORNIA AND AN ANALYSIS OF THE ROLE OF LIFE HISTORY TRAITS ON PARASITE RICHNESS

    PubMed Central

    Hannon, Emily R.; Kinsella, John M.; Calhoun, Dana M.; Joseph, Maxwell B.; Johnson, Pieter T. J.

    2016-01-01

    The life history characteristics of hosts often influence patterns of parasite infection either by affecting the likelihood of parasite exposure or the probability of infection following exposure. In birds, migratory behavior has been suggested to affect both the composition and abundance of parasites within a host, although whether migratory birds have more or fewer parasites is unclear. To help address these knowledge gaps, we collaborated with airports, animal rescue/rehabilitation centers, and hunter check stations in the San Francisco Bay Area of California to collect 57 raptors, egrets, herons, ducks, and other waterfowl for parasitological analysis. Following dissections of the gastro-intestinal tract of each host, we identified 64 taxa of parasites: 5 acanthocephalans, 24 nematodes, 8 cestodes, and 27 trematodes. We then used a generalized linear mixed model to determine how life history traits influenced parasite richness among bird hosts, while controlling for host phylogeny. Parasite richness was greater in birds that were migratory with larger clutch sizes and lower in birds that were herbivorous. The effects of clutch size and diet are consistent with previous studies and have been linked to immune function and parasite exposure, respectively, whereas the effect of migration supports the hypothesis of ‘migratory exposure’ rather than that of ‘migratory escape’. PMID:26579621

  7. Vocal matching and intensity of begging calls are associated with a forebrain song circuit in a generalist brood parasite.

    PubMed

    Liu, Wan-Chun; Rivers, James W; White, David J

    2016-06-01

    Vocalizations produced by developing young early in life have simple acoustic features and are thought to be innate. Complex forms of early vocal learning are less likely to evolve in young altricial songbirds because the forebrain vocal-learning circuit is underdeveloped during the period when early vocalizations are produced. However, selective pressure experienced in early postnatal life may lead to early vocal learning that is likely controlled by a simpler brain circuit. We found the food begging calls produced by fledglings of the brown-headed cowbird (Molothrus ater), a generalist avian brood parasite, induced the expression of several immediate early genes and early circuit innervation in a forebrain vocal-motor pathway that is later used for vocal imitation. The forebrain neural activity was correlated with vocal intensity and variability of begging calls that appears to allow cowbirds to vocally match host nestmates. The begging-induced forebrain circuits we observed in fledgling cowbirds were not detected in nonparasitic passerines, including species that are close relatives to the cowbird. The involvement of forebrain vocal circuits during fledgling begging and its association with vocal learning plasticity may be an adaptation that provides young generalist brood parasites with a flexible signaling strategy to procure food from a wide range of heterospecific host parents.

  8. Occurrence, prevalence and intensity of internal parasite infections of African lions (Panthera leo) in enclosures at a recreation park in Zimbabwe.

    PubMed

    Mukarati, Norman L; Vassilev, George D; Tagwireyi, Whatmore M; Tavengwa, Michael

    2013-09-01

    A coprological survey was conducted to determine the types, prevalence, and intensity of infection of internal parasites in a population of captive African lions (Panthera leo) at a recreational game park in Zimbabwe. Individual fecal samples were collected on three occasions over a 4-month period from each of 30 lions (55%) out of 55 animals held. The samples were examined using flotation and sedimentation techniques to assess the presence and count of parasite eggs, oocysts, and cysts per gram of feces as well as larvae identification. The overall prevalence of helminth infections was 100% (30/30), and 80% (24/30) of fecal samples also were positive for protozoan parasite forms. Eggs of Ancylostoma spp. were found in the feces of 23 (76.7%) lions, Physaloptera sp. in 14 (46.7%) lions, Toxascaris leonina in 13 (43.3%) lions, Toxocara cati in 12 (40%) lions, and Gnathostoma spinigerum and Toxocara canis in 2 (6.7%) lions. Furthermore, eggs of Cylicospirura subequalis, Gnathostoma spp., Lagochilascaris major, Acanthocephalan and Linguatula spp. as well as larvae of Aelurostrongylus sp. were identified in the feces of one lion. Oocysts of five apicomplexan parasites and cysts of one mastigophoran protozoan parasite were recorded, namely, Cystoisospora leonina in 11 (36.7%) lions' feces, Cystoisospora spp. in 9 (30.0%) lions, Cystoisospora felis in 5 (16.7%) lions; Toxoplasma-like spp. in 5 (16.7 %) lions, and Giardia spp. in 8 (26.7%) lions. The majority of lions (28/30) showed mixed infections with different internal parasites, whereas only two animals had single parasite infections. The intensity of infection was relatively low. Some parasite forms observed and identified, such as Eimeria spp. oocysts, were spurious and probably originated from the prey species for the lions. Among the parasites identified were some of zoonotic importance that have health implications for at-risk personnel and visitors who get into contact with the animals.

  9. Parasites of domestic owned cats in Europe: co-infestations and risk factors

    PubMed Central

    2014-01-01

    Background Domestic cats can be infested by a large range of parasite species. Parasitic infestations may cause very different clinical signs. Endoparasites and ectoparasites are rarely explored in the same study and therefore multiparasitism is poorly documented. The present survey aimed to improve knowledge of the prevalence and risk factors associated with ecto- and endoparasite infestations in owned cats in Europe. Methods From March 2012 to May 2013, 1519 owned cats were included in a multicenter study conducted in 9 veterinary faculties throughout Europe (Austria, Belgium, France, Hungary, Italy, Romania and Spain). For each cat, ectoparasites were checked by combing of the coat surface associated with otoscopic evaluation and microscopy on cerumen samples. Endoparasites were identified by standard coproscopical examinations performed on fresh faecal samples. Risk factors and their influence on parasitism were evaluated by univariate analysis followed by a multivariate statistical analysis (including center of examination, age, outdoor access, multipet status, and frequency of treatments as main criteria) with logistic regression models. Results Overall, 50.7% of cats resulted positive for at least one internal or one external parasite species. Ectoparasites were found in 29.6% of cats (CI95 27.3-32.0%). Otodectes cynotis was the most frequently identified species (17.4%), followed by fleas (15.5%). Endoparasites were identified in 35.1% of the cats (CI95 32.7-35.7%), including gastro-intestinal helminths in 25.7% (CI95 23.5-28.0), respiratory nematodes in 5.5% (CI95 4.2-7.0%) and protozoans in 13.5% (CI95 11.8-15.3%). Toxocara cati was the most commonly diagnosed endoparasite (19.7%, CI95 17.8-21.8%). Co-infestation with endoparasites and ectoparasites was found in 14.0% of the cats, and 11.9% harbored both ectoparasites and gastro-intestinal helminths. Age, outdoor access, living with other pets, and anthelmintic or insecticide treatments were significantly

  10. Manipulation of host-resource dynamics impacts transmission of trophic parasites.

    PubMed

    Luong, Lien T; Grear, Daniel A; Hudson, Peter J

    2014-09-01

    Many complex life cycle parasites rely on predator-prey interactions for transmission, whereby definitive hosts become infected via the consumption of an infected intermediate host. As such, these trophic parasites are embedded in the larger community food web. We postulated that exposure to infection and, hence, parasite transmission are inherently linked to host foraging ecology, and that perturbation of the host-resource dynamic will impact parasite transmission dynamics. We employed a field manipulation experiment in which natural populations of the eastern chipmunk (Tamias striatus) were provisioned with a readily available food resource in clumped or uniform spatial distributions. Using replicated longitudinal capture-mark-recapture techniques, replicated supplemented and unsupplemented control sites were monitored before and after treatment for changes in infection levels with three gastro-intestinal helminth parasites. We predicted that definitive hosts subject to food supplementation would experience lower rates of exposure to infective intermediate hosts, presumably because they shifted their diet away from the intermediate host towards the more readily available resource (sunflower seeds). As predicted, prevalence of infection by the trophically transmitted parasite decreased in response to supplemental food treatment, but no such change in infection prevalence was detected for the two directly transmitted parasites in the system. The fact that food supplementation only had an impact on the transmission of the trophically transmitted parasite, and not the directly transmitted parasites, supports our hypothesis that host foraging ecology directly affects exposure to parasites that rely on the ingestion of intermediate hosts for transmission. We concluded that the relative availability of different food resources has important consequences for the transmission of parasites and, more specifically, parasites that are embedded in the food web. The broader

  11. Immunoepidemiology of Wuchereria bancrofti Infection: Parasite Transmission Intensity, Filaria-Specific Antibodies, and Host Immunity in Two East African Communities▿

    PubMed Central

    Jaoko, Walter G.; Michael, Edwin; Meyrowitsch, Dan W.; Estambale, Benson B. A.; Malecela, Mwele N.; Simonsen, Paul E.

    2007-01-01

    We compared the age profiles of infection and specific antibody intensities in two communities with different transmission levels in East Africa to examine the contribution of humoral responses to human immunity to the vector-borne helminth Wuchereria bancrofti. The worm intensities were higher and exhibited a nonlinear age pattern in a high-transmission community, Masaika, in contrast to the low but linearly increasing age infection profile observed for a low-transmission community, Kingwede. The mean levels of specific immunoglobulin G1 (IgG1), IgG2, IgG4, and IgE were also higher in Masaika, but intriguingly, the IgG3 response was higher in Kingwede. The age-antibody patterns differed in the two communities but in a manner apparently contrary to a role in acquired immunity when the data were assessed using simple correlation methods. By contrast, multivariate analyses showed that the antibody response to infection may be classified into three types and that two of these types, a IgG3-type response and a response measuring a trade-off in host production of IgG4 and IgG3 versus production of IgG1, IgG2, and IgE, had a negative effect on Wuchereria circulating antigen levels in a manner that supported a role for these responses in the generation of acquired immunity to infection. Mathematical modeling supported the conclusions drawn from empirical data analyses that variations in both transmission and worm intensity can explain community differences in the age profiles and impacts of these antibody response types. This study showed that parasite-specific antibody responses may be associated with the generation of acquired immunity to human filarial infection but in a form which is dependent on worm transmission intensity and interactions between immune components. PMID:17908811

  12. Light Intensity and Quality Effects on Reproduction of Plant-Parasitic Nematodes

    PubMed Central

    Barker, K. R.; Hussey, R. S.; Yang, H.

    1975-01-01

    Growing cotton in a greenhouse with 12-h of supplemental light [8,608 lux (800 ft-c) from combination of mercury and Lucalux® lamps] resulted in 2 × to > 3 × greater reproduction of Meloidogyne incognita and Belonolaimus longicaudatus as compared to natural light alone. Rate of increase of Hoplolaimus galeatus was affected little in this experiment. In a second experiment under controlled conditions in a phytotron, light source and intensity had greater influence on the reproduction of Heterodera glycines and Pratylenchus penetrans on soybean than on B. longicaudatus. Fluorescent plus incandescent and metal halide light sources resulted in the greatest nematode reproduction. Lucalux lamps resulted in much lower rates of nematode increase than other light sources. Rates of nematode increase on soybean under the different light sources in the phytotron generally were positively related to plant growth. PMID:19308183

  13. Intravenous Artesunate Reduces Parasite Clearance Time, Duration of Intensive Care, and Hospital Treatment in Patients With Severe Malaria in Europe: The TropNet Severe Malaria Study.

    PubMed

    Kurth, Florian; Develoux, Michel; Mechain, Matthieu; Clerinx, Jan; Antinori, Spinello; Gjørup, Ida E; Gascon, Joaquím; Mørch, Kristine; Nicastri, Emanuele; Ramharter, Michael; Bartoloni, Alessandro; Visser, Leo; Rolling, Thierry; Zanger, Philipp; Calleri, Guido; Salas-Coronas, Joaquín; Nielsen, Henrik; Just-Nübling, Gudrun; Neumayr, Andreas; Hachfeld, Anna; Schmid, Matthias L; Antonini, Pietro; Pongratz, Peter; Kern, Peter; Saraiva da Cunha, José; Soriano-Arandes, Antoni; Schunk, Mirjam; Suttorp, Norbert; Hatz, Christoph; Zoller, Thomas

    2015-11-01

    Intravenous artesunate improves survival in severe malaria, but clinical trial data from nonendemic countries are scarce. The TropNet severe malaria database was analyzed to compare outcomes of artesunate vs quinine treatment. Artesunate reduced parasite clearance time and duration of intensive care unit and hospital treatment in European patients with imported severe malaria.

  14. Palliative intensity modulated radiation therapy for symptomatic adrenal metastasis.

    PubMed

    Mod, H; Patel, V

    2013-05-01

    Metastasis to the adrenal glands is quite common; especially from melanomas, breast, lung, renal and gastro-intestinal tumours. The most common tumour found in the adrenals in post mortem series is a metastatic tumour; incidence ranging from 13 to 27%. The diagnosis of adrenal metastasis is now more common and easier due to staging and subsequent follow up with Computed tomography /Magnetic resonance imaging and or positron emission tomography-computed tomography imaging studies. Most of the times these metastatic lesions are clinically occult and those that do have clinical symptoms complain of pain, nausea, vomiting and early satiety. We irradiated a patient of non small cell lung cancer with adrenal metastasis with palliative Intensity Modulated Radiation Therapy and achieved a good response in terms of pain relief, stable disease and no side effects of the treatment.

  15. Bioluminescence imaging of chronic Trypanosoma cruzi infections reveals tissue-specific parasite dynamics and heart disease in the absence of locally persistent infection

    PubMed Central

    Lewis, Michael D; Fortes Francisco, Amanda; Taylor, Martin C; Burrell-Saward, Hollie; McLatchie, Alex P; Miles, Michael A; Kelly, John M

    2014-01-01

    Summary Chronic Trypanosoma cruzi infections lead to cardiomyopathy in 20–30% of cases. A causal link between cardiac infection and pathology has been difficult to establish because of a lack of robust methods to detect scarce, focally distributed parasites within tissues. We developed a highly sensitive bioluminescence imaging system based on T. cruzi expressing a novel luciferase that emits tissue-penetrating orange-red light. This enabled long-term serial evaluation of parasite burdens in individual mice with an in vivo limit of detection of significantly less than 1000 parasites. Parasite distributions during chronic infections were highly focal and spatiotemporally dynamic, but did not localize to the heart. End-point ex vivo bioluminescence imaging allowed tissue-specific quantification of parasite loads with minimal sampling bias. During chronic infections, the gastro-intestinal tract, specifically the colon and stomach, was the only site where T. cruzi infection was consistently observed. Quantitative PCR-inferred parasite loads correlated with ex vivo bioluminescence and confirmed the gut as the parasite reservoir. Chronically infected mice developed myocarditis and cardiac fibrosis, despite the absence of locally persistent parasites. These data identify the gut as a permissive niche for long-term T. cruzi infection and show that canonical features of Chagas disease can occur without continual myocardium-specific infection. PMID:24712539

  16. Clonal diversity of a lizard malaria parasite, Plasmodium mexicanum, in its vertebrate host, the western fence lizard: role of variation in transmission intensity over time and space.

    PubMed

    Vardo, A M; Schall, J J

    2007-07-01

    Within the vertebrate host, infections of a malaria parasite (Plasmodium) could include a single genotype of cells (single-clone infections) or two to several genotypes (multiclone infections). Clonal diversity of infection plays an important role in the biology of the parasite, including its life history, virulence, and transmission. We determined the clonal diversity of Plasmodium mexicanum, a lizard malaria parasite at a study region in northern California, using variable microsatellite markers, the first such study for any malaria parasite of lizards or birds (the most common hosts for Plasmodium species). Multiclonal infections are common (50-88% of infections among samples), and measures of genetic diversity for the metapopulation (expected heterozygosity, number of alleles per locus, allele length variation, and effective population size) all indicated a substantial overall genetic diversity. Comparing years with high prevalence (1996-1998 = 25-32% lizards infected), and years with low prevalence (2001-2005 = 6-12%) found fewer alleles in samples taken from the low-prevalence years, but no reduction in overall diversity (H = 0.64-0.90 among loci). In most cases, rare alleles appeared to be lost as prevalence declined. For sites chronically experiencing low transmission intensity (prevalence approximately 1%), overall diversity was also high (H = 0.79-0.91), but there were fewer multiclonal infections. Theory predicts an apparent excess in expected heterozygosity follows a genetic bottleneck. Evidence for such a distortion in genetic diversity was observed after the drop in parasite prevalence under the infinite alleles mutation model but not for the stepwise mutation model. The results are similar to those reported for the human malaria parasite, Plasmodium falciparum, worldwide, and support the conclusion that malaria parasites maintain high genetic diversity in host populations despite the potential for loss in alleles during the transmission cycle or

  17. Environmental variables and definitive host distribution: a habitat suitability modelling for endohelminth parasites in the marine realm.

    PubMed

    Kuhn, Thomas; Cunze, Sarah; Kochmann, Judith; Klimpel, Sven

    2016-08-10

    Marine nematodes of the genus Anisakis are common parasites of a wide range of aquatic organisms. Public interest is primarily based on their importance as zoonotic agents of the human Anisakiasis, a severe infection of the gastro-intestinal tract as result of consuming live larvae in insufficiently cooked fish dishes. The diverse nature of external impacts unequally influencing larval and adult stages of marine endohelminth parasites requires the consideration of both abiotic and biotic factors. Whereas abiotic factors are generally more relevant for early life stages and might also be linked to intermediate hosts, definitive hosts are indispensable for a parasite's reproduction. In order to better understand the uneven occurrence of parasites in fish species, we here use the maximum entropy approach (Maxent) to model the habitat suitability for nine Anisakis species accounting for abiotic parameters as well as biotic data (definitive hosts). The modelled habitat suitability reflects the observed distribution quite well for all Anisakis species, however, in some cases, habitat suitability exceeded the known geographical distribution, suggesting a wider distribution than presently recorded. We suggest that integrative modelling combining abiotic and biotic parameters is a valid approach for habitat suitability assessments of Anisakis, and potentially other marine parasite species.

  18. Kidney pathology and parasite intensity in rainbow trout Oncorhynchus mykiss surviving proliferative kidney disease: time course and influence of temperature.

    PubMed

    Schmidt-Posthaus, Heike; Bettge, Kathrin; Forster, Ursula; Segner, Helmut; Wahli, Thomas

    2012-01-24

    Proliferative kidney disease (PKD) is an endoparasitic disease of salmonids caused by the myxozoan parasite Tetracapsuloides bryosalmonae. We recently described the development of the disease from initial infection until manifestation of clinical disease signs in rainbow trout held at 2 water temperatures, 12 and 18°C. The aim of the present study is to investigate whether (1) infected fish surviving the clinical phase would recover from renal pathological changes, (2) whether they would be able to reduce the parasite load in the kidneys, and (3) whether water temperatures would influence renal recovery and parasite clearance. At 18°C, fish showed a gradual recovery of normal kidney morphology which was associated with a decline in parasite numbers and infection prevalence. Fish kept at 12°C initially showed an enhancement of kidney lesions before recovery of normal kidney morphology took place. The decrease in renal parasite load was retarded compared to 18°C. The results from the present study provide evidence that rainbow trout surviving the clinical phase of PKD are able to (1) fully restore renal structure, and (2) significantly reduce renal parasite loads, although 100% clearance was not achieved within the experimental period of this study. Water temperature influences the rate but not the outcome of the recovery process.

  19. Environmental variables and definitive host distribution: a habitat suitability modelling for endohelminth parasites in the marine realm

    PubMed Central

    Kuhn, Thomas; Cunze, Sarah; Kochmann, Judith; Klimpel, Sven

    2016-01-01

    Marine nematodes of the genus Anisakis are common parasites of a wide range of aquatic organisms. Public interest is primarily based on their importance as zoonotic agents of the human Anisakiasis, a severe infection of the gastro-intestinal tract as result of consuming live larvae in insufficiently cooked fish dishes. The diverse nature of external impacts unequally influencing larval and adult stages of marine endohelminth parasites requires the consideration of both abiotic and biotic factors. Whereas abiotic factors are generally more relevant for early life stages and might also be linked to intermediate hosts, definitive hosts are indispensable for a parasite’s reproduction. In order to better understand the uneven occurrence of parasites in fish species, we here use the maximum entropy approach (Maxent) to model the habitat suitability for nine Anisakis species accounting for abiotic parameters as well as biotic data (definitive hosts). The modelled habitat suitability reflects the observed distribution quite well for all Anisakis species, however, in some cases, habitat suitability exceeded the known geographical distribution, suggesting a wider distribution than presently recorded. We suggest that integrative modelling combining abiotic and biotic parameters is a valid approach for habitat suitability assessments of Anisakis, and potentially other marine parasite species. PMID:27507328

  20. Environmental variables and definitive host distribution: a habitat suitability modelling for endohelminth parasites in the marine realm

    NASA Astrophysics Data System (ADS)

    Kuhn, Thomas; Cunze, Sarah; Kochmann, Judith; Klimpel, Sven

    2016-08-01

    Marine nematodes of the genus Anisakis are common parasites of a wide range of aquatic organisms. Public interest is primarily based on their importance as zoonotic agents of the human Anisakiasis, a severe infection of the gastro-intestinal tract as result of consuming live larvae in insufficiently cooked fish dishes. The diverse nature of external impacts unequally influencing larval and adult stages of marine endohelminth parasites requires the consideration of both abiotic and biotic factors. Whereas abiotic factors are generally more relevant for early life stages and might also be linked to intermediate hosts, definitive hosts are indispensable for a parasite’s reproduction. In order to better understand the uneven occurrence of parasites in fish species, we here use the maximum entropy approach (Maxent) to model the habitat suitability for nine Anisakis species accounting for abiotic parameters as well as biotic data (definitive hosts). The modelled habitat suitability reflects the observed distribution quite well for all Anisakis species, however, in some cases, habitat suitability exceeded the known geographical distribution, suggesting a wider distribution than presently recorded. We suggest that integrative modelling combining abiotic and biotic parameters is a valid approach for habitat suitability assessments of Anisakis, and potentially other marine parasite species.

  1. Characterization of Romboutsia ilealis gen. nov., sp. nov., isolated from the gastro-intestinal tract of a rat, and proposal for the reclassification of five closely related members of the genus Clostridium into the genera Romboutsia gen. nov., Intestinibacter gen. nov., Terrisporobacter gen. nov. and Asaccharospora gen. nov.

    PubMed

    Gerritsen, Jacoline; Fuentes, Susana; Grievink, Wieke; van Niftrik, Laura; Tindall, Brian J; Timmerman, Harro M; Rijkers, Ger T; Smidt, Hauke

    2014-05-01

    A Gram-positive staining, rod-shaped, non-motile, spore-forming obligately anaerobic bacterium, designated CRIBT, was isolated from the gastro-intestinal tract of a rat and characterized. The major cellular fatty acids of strain CRIBT were saturated and unsaturated straight-chain C12-C19 fatty acids, with C16:0 being the predominant fatty acid. The polar lipid profile comprised six glycolipids, four phospholipids and one lipid that did not stain with any of the specific spray reagents used. The only quinone was MK-6. The predominating cell-wall sugars were glucose and galactose. The peptidoglycan type of strain CRIBT was A1σ lanthionine-direct. The genomic DNA G+C content of strain CRIBT was 28.1 mol%. On the basis of 16S rRNA gene sequence similarity, strain CRIBT was most closely related to a number of species of the genus Clostridium, including Clostridium lituseburense (97.2%), Clostridium glycolicum (96.2%), Clostridium mayombei (96.2%), Clostridium bartlettii (96.0%) and Clostridium irregulare (95.5%). All these species show very low 16S rRNA gene sequence similarity (<85%) to the type strain of Clostridium butyricum, the type species of the genus Clostridium. DNA-DNA hybridization with closely related reference strains indicated reassociation values below 32%. On the basis of phenotypic and genetic studies, a novel genus, Romboutsia gen. nov., is proposed. The novel isolate CRIBT (=DSM 25109T=NIZO 4048T) is proposed as the type strain of the type species, Romboutsia ilealis gen. nov., sp. nov., of the proposed novel genus. It is proposed that C. lituseburense is transferred to this genus as Romboutsia lituseburensis comb. nov. Furthermore, the reclassification into novel genera is proposed for C. bartlettii, as Intestinibacter bartlettii gen. nov., comb. nov. (type species of the genus), C. glycolicum, as Terrisporobacter glycolicus gen. nov., comb. nov. (type species of the genus), C. mayombei, as Terrisporobacter mayombei gen. nov., comb. nov., and C

  2. Microhabitat use, not temperature, regulates intensity of Gyrodactylus cichlidarum long-term infection on farmed tilapia--are parasites evading competition or immunity?

    PubMed

    Rubio-Godoy, Miguel; Muñoz-Córdova, Germán; Garduño-Lugo, Mario; Salazar-Ulloa, Martha; Mercado-Vidal, Gabriel

    2012-02-10

    with increased intensity of infection; as well as the opposite, where increased aggregation coincided with parasite population declines. Three alternative explanations could account for these observations: that parasites (1) experience differential mortality on different anatomical regions of the fish; (2) migrate to avoid intraspecific competition; and (3) migrate to escape localized immune responses induced by infection. Our data do not allow us to demonstrate which of these alternatives is correct, so we discuss the merits of each. We provide circumstantial evidence in support of the third explanation, because as shown in other fish host-gyrodactylid interactions where immune responses have been characterized, in this study worms progressively moved away from fins with high mucus cell density to those with low density - what would be anticipated if immune defenses occur and reach the fish surface through mucus.

  3. Parasites and supernormal manipulation.

    PubMed Central

    Holen, Ø. H.; Saetre, G. P.; Slagsvold, T.; Stenseth, N. C.

    2001-01-01

    Social parasites may exploit their hosts by mimicking other organisms that the hosts normally benefit from investing in or responding to in some other way. Some parasites exaggerate key characters of the organisms they mimic, possibly in order to increase the response from the hosts. The huge gape and extreme begging intensity of the parasitic common cuckoo chick (Cuculus canorus) may be an example. In this paper, the evolutionary stability of manipulating hosts through exaggerated signals is analysed using game theory. Our model indicates that a parasite's signal intensity must be below a certain threshold in order to ensure acceptance and that this threshold depends directly on the rate of parasitism. The only evolutionarily stable strategy (ESS) combination is when hosts accept all signallers and parasites signal at their optimal signal intensity, which must be below the threshold. Supernormal manipulation by parasites is only evolutionarily stable under sufficiently low rates of parasitism. If the conditions for the ESS combination are not satisfied, rejector hosts can invade using signal intensity as a cue for identifying parasites. These qualitative predictions are discussed with respect to empirical evidence from parasitic mimicry systems that have been suggested to involve supernormal signalling, including evicting avian brood parasites and insect-mimicking Ophrys orchids. PMID:11749709

  4. [Parenteral nutrition in gastro-intestinal surgery (author's transl)].

    PubMed

    Rosa, M P; Steuve, J; Houben, J J; Niederkorn, A; Govaerts, J P

    1981-01-01

    Forty-two postoperative patients received by parenteral route on 24 hours a total of 2,610 calories by means of a simultaneous infusion of 1,500 ml Trivé 1000 and 1,500 ml 10% invert sugar through a central venous line. Of those 42 cases 12 had peritonitis with 7 of them an enteric fistula, 18 underwent an extensive bowel resection and 12 suffered malnutrition secondary to their primary pathology. The average duration of parenteral nutrition was 13 days and the average hospital stay 27 days. No major metabolic derangement was noted except for a temporary transient elevation of SGOT and AF. A systematic bacteriological study of the perfusion lines disclosed an associated morbidity of about 6%. We are convinced that with the used solutions the postoperative catabolism can be managed successfully and that the association of aminoacids, lipids and glucides as used by us facilitates, nursing care.

  5. Battery acid burns of the upper gastro-intestinal tract.

    PubMed

    Wormald, P J; Wilson, D A

    1993-04-01

    Strong acid ingestion produces distinctly different injuries from alkali burns. Alkali burns are well described but the lack of literature on the diagnosis and management of acid burns is apparent. This retrospective review of 18 patients with battery acid (30% sulphuric acid) ingestion showed no correlation between the severity of the symptomatology and the degree of injury. The quantity of acid needed to cause a significant upper GIT burn was more than 200 ml. Previous reports that acid spared the oesophagus due to rapid transit were disproved, since oesophageal involvement was found in 55% (10/18). Deep burns rather than circumferential burns resulted in stricture formation. The major injury site was the gastric antrum with 4 patients (23%) requiring surgical intervention to restore function.

  6. Eosinophilic disorders of the gastro-intestinal tract: an update.

    PubMed

    Ridolo, Erminia; Melli, Valerie; De' Angelis, Gianluigi; Martignago, Irene

    2016-01-01

    Eosinophilic diseases of the gastrointestinal tract, including eosinophilic esophagitis (EoE) and eosinophilic gastroenteritis (EGE), are rare chronic pathologies of the digestive system, with an immuno-mediated pathogenesis. Recent data suggest that, together with the "classic" IgE-response to allergens, also a delayed hypersensitivity mechanism could be involved in the development of eosinophilic disorders. EoE and EGE were studied only in the latest decades and as a consequence accurate data are not yet available, concerning not only pathogenesis, but also epidemiology, treatment and outcomes. The diagnosis of EoE is centered on endoscopic findings but the certainty is obtained by histological examination from biopsy samples, that has a sensitivity of 100% when based on five samples. The currently available treatments include topical corticosteroids, specific diets and endoscopic treatment. Concerning EGE, three subtypes (mucosal, muscular, and serosal) were identified. The diagnosis is based, as for EoE, on endoscopic and histological assessment, and the treatment includes pharmacological and dietetic approaches. Further studies are warranted in order to better define the etiology and pathogenesis of eosinophilic diseases of the gastrointestinal tract, and thus to develop more appropriate and specific therapies.

  7. Gallbladder Duplication Associated with Gastro-Intestinal Atresia

    PubMed Central

    Gupta, Rahul; Gupta, Shilpi; Sharma, Pramila; Bhandari, Anu; Gupta, Arun Kumar; Mathur, Praveen

    2016-01-01

    Gallbladder duplication in association with other GIT anomalies is a rare entity. We report two neonates; one with duodenal atresia and the other newborn with pyloric atresia, ileal atresia and colonic atresia, both were associated with gallbladder duplication which has not been reported earlier. PMID:27123398

  8. Association between variation in faecal egg count for a natural mixed field-challenge of nematode parasites and TLR4 variation.

    PubMed

    Lin, Y-S; Zhou, H; Forrest, R H J; Frampton, C M; Burrows, L E R; Hickford, J G H

    2016-03-15

    Research has shown that Toll-like receptor 4 (TLR4) is important in immune responses to some helminth parasites. In sheep, variation in the PAMP region of TLR4 may result in structurally and thus functionally different TLR4 molecules, and this may consequently lead to variation in the TLR4 response to parasite infections. This study involved three separate, but related sheep breeds (Merino, Polwarth and Corriedale sheep) and a total of 885 lambs from five New Zealand farms that underwent a mixed field-challenge from gastro-intestinal parasites. Faecal samples were collected at approximately 4 and 9 months of age and faecal egg counts (FECs) for Nematodirus spp. and Strongyle species determined, along with the total number of eggs per gram (EPG). Analysis of the five farms collectively revealed an association (P=0.023) between the presence of TLR4 variant *02 (mean 24 EPG) and the absence of the variant (mean 32 EPG) at 9 months of age. Conversely the presence of *03 had a significantly (P=0.047) higher mean Nematodirus spp. FEC (mean 42 EPG) compared to the absence (mean 28 EPG) at 9 months of age. More associations were revealed when the data were split according to the dominant faecal parasite species. With a predominantly Trichostrongylus spp. FEC group of lambs at 9 months of age, the presence of TLR4 variant *02 was found to have significantly (P=0.003) lower Nematodirus spp. FEC (mean 4 EPG), and also significantly (P=0.033) lower total FEC (mean 312 EPG) when compared to sheep without the variant (mean 15 EPG and 449 EPG, respectively). The presence of TLR4 variant *03 and *04 were associated or tended to be associated (P=0.010 and P=0.088, respectively) with higher Nematodirus spp. FEC (mean 25 EPG and 22 EPG, respectively) when compared to lambs without the variant (mean 10 EPG and 11 EPG, respectively). These results suggest that TLR4 variation may be affecting the immune response to gastro-intestinal parasites in sheep, although principally to

  9. Euduboscquella costata n. sp. (Dinoflagellata, Syndinea), an Intracellular Parasite of the Ciliate Schmidingerella arcuata: Morphology, Molecular Phylogeny, Life Cycle, Prevalence, and Infection Intensity.

    PubMed

    Jung, Jae-Ho; Choi, Jung Min; Coats, D Wayne; Kim, Young-Ok

    2016-01-01

    The syndinean dinoflagellate Euduboscquella costata n. sp., an intracellular parasite of the tintinnid ciliate Schmidingerella arcuata, was discovered from Korean coastal water in November of 2013. Euduboscquella costata parasitized in about 62% of the host population, with infection intensity (= number of trophonts in a single host cell) ranging from 1 to 8. Based on morphology and nuclear 18S ribosomal RNA gene sequences, the parasite is new to science. Euduboscquella costata n. sp. had an infection cycle typical of the genus, but had morphological and developmental features that distinguished it from congeneric species. These features include: (1) episome of the trophont with 25-40 grooves converging toward the center of the shield; (2) a narrow, funnel-shaped lamina pharyngea extending from the margin of the episomal shield to the nucleus; (3) persistence of grooves during extracellular development (sporogenesis); (4) a single food vacuole during sporogenesis; (5) separation of sporocytes early in sporogenesis, regardless of type of spore formed; and (6) dinospore size (ca. 14 μm in length) and shape (bulbous episome with narrower, tapering hyposome). After sporogenesis, E. costata produced four different types of spore that showed completely identical 18S rRNA gene sequences. The gene sequence was completely identical with a previously reported population, Euduboscquella sp. ex S. arcuata, from Assawoman Bay, USA, indicating that the two populations are likely conspecific. Favella ehrenbergii, a widely recorded tintinnid known to host Euduboscquella spp., co-occurred with S. arcuata, but was not infected by E. costata in field samples or during short-term, cross-infection experiments. © 2015 The Author(s) Journal of Eukaryotic Microbiology © 2015 International Society of Protistologists.

  10. Economic values of body weight, reproduction and parasite resistance traits for a Creole goat breeding goal.

    PubMed

    Gunia, M; Mandonnet, N; Arquet, R; Alexandre, G; Gourdine, J-L; Naves, M; Angeon, V; Phocas, F

    2013-01-01

    A specific breeding goal definition was developed for Creole goats in Guadeloupe. This local breed is used for meat production. To ensure a balanced selection outcome, the breeding objective included two production traits, live weight (BW11) and dressing percentage (DP) at 11 months (the mating or selling age), one reproduction trait, fertility (FER), and two traits to assess animal response to parasite infection: packed cell volume (PCV), a resilience trait, and faecal worm eggs count (FEC), a resistance trait. A deterministic bio-economic model was developed to calculate the economic values based on the description of the profit of a Guadeloupean goat farm. The farm income came from the sale of animals for meat or as reproducers. The main costs were feeding and treatments against gastro-intestinal parasites. The economic values were 7.69€ per kg for BW11, 1.38€ per % for FER, 3.53€ per % for DP and 3 × 10(-4)€ per % for PCV. The economic value for FEC was derived by comparing the expected profit and average FEC in a normal situation and in an extreme situation where parasites had developed resistance to anthelmintics. This method yielded a maximum weighting for FEC, which was -18.85€ per log(eggs per gram). Alternative scenarios were tested to assess the robustness of the economic values to variations in the economic and environmental context. The economic values of PCV and DP were the most stable. Issues involved in paving the way for selective breeding on resistance or resilience to parasites are discussed.

  11. Simulated selection responses for breeding programs including resistance and resilience to parasites in Creole goats.

    PubMed

    Gunia, M; Phocas, F; Gourdine, J-L; Bijma, P; Mandonnet, N

    2013-02-01

    The Creole goat is a local breed used for meat production in Guadeloupe (French West Indies). As in other tropical countries, improvement of parasite resistance is needed. In this study, we compared predicted selection responses for alternative breeding programs with or without parasite resistance and resilience traits. The overall breeding goal included traits for production, reproduction, and parasite resilience and resistance to ensure a balanced selection outcome. The production traits were BW and dressing percentage (DP). The reproduction trait was fertility (FER), which was the number of doe kiddings per mating. The resistance trait was worm fecal egg count (FEC), which is a measurement of the number of gastro-intestinal parasite eggs found in the feces. The resilience trait was the packed cell volume (PCV), which is a measurement of the volume of red blood cells in the blood. Dressing percentage, BW, and FEC were measured at 11 mo of age, which is the mating or selling age. Fertility and PCV were measured on females at each kidding period. The breeding program accounting for the overall breeding goal and a selection index including all traits gave annual selection responses of 800 g for BW, 3.75% for FER, 0.08% for DP, -0.005 ln(eggs/g) for FEC, and 0.28% for PCV. The expected selection responses for BW and DP in this breeding program were reduced by 2% and 6%, respectively, compared with a breeding program not accounting for FEC and PCV. The overall breeding program, proposed for the Creole breed, offers the best breeding strategy in terms of expected selection responses, making it possible to improve all traits together. It offers a good balance between production and adaptation traits and may present some interest for the selection of other goat breeds in the tropics.

  12. Parasitic Diseases

    MedlinePlus

    ... a bug bite, or sexual contact. Some parasitic diseases are easily treated and some are not. Parasites ... be seen with the naked eye. Some parasitic diseases occur in the United States. Contaminated water supplies ...

  13. Prevalence and risk factors for gastrointestinal parasitism in traditionally maintained goat flocks of South Gujarat.

    PubMed

    Sorathiya, L M; Fulsoundar, A B; Rao, T K S; Kumar, Niranjan

    2017-03-01

    A total of 360 faecal samples of goat belonging to Ahir community were collected randomly from eight villages on monthly basis. On same day, collected samples were subjected to qualitative faecal examination and positive samples were categorized into mild, moderate and heavy infected groups. The risk factors considered for study were age, pregnancy, lactation, seasons, wet land grazing and hygiene in housing. Overall 41.11 % animals were found positive for helminth eggs and among them 24.17, 10.56 and 6.39 % of goats were mildly, moderately and heavily infected, respectively. The helminths recorded were strongyles (26.9 %), amphistomes (18.1 %), Trichuris spp. (8.1 %) and Nematoidirus spp. (3.9 %). Similarly, 72 (20 %) animals were found positive for presence of coccidia oocysts in which 13.06, 4.17 and 2.78 % were having mild, moderate and heavy infection. The Chi square test revealed that the housing quality, seasons and body condition scores (BCS) were having significant effects on helminths prevalence. The Chi square values indicated that age, hygiene of houses, seasons and BCS have significantly associated with prevalence of coccidiosis. The helminths prevalence was having significant positive correlation with lactation status and housing quality whereas it was significantly negatively correlated with prevalence of coccidia. Kendall's Correlation coefficients among various risk factors reveals that age and housing quality has significant negative correlations with coccidia infection. The gastro-intestinal (GI) parasites incidence was significantly high during the monsoon than the summer/winter season. The correlation of GI- parasitic prevalence with pregnancy status and age was not found.

  14. Interacting parasites

    USGS Publications Warehouse

    Lafferty, Kevin D.

    2010-01-01

    Parasitism is the most popular life-style on Earth, and many vertebrates host more than one kind of parasite at a time. A common assumption is that parasite species rarely interact, because they often exploit different tissues in a host, and this use of discrete resources limits competition (1). On page 243 of this issue, however, Telfer et al. (2) provide a convincing case of a highly interactive parasite community in voles, and show how infection with one parasite can affect susceptibility to others. If some human parasites are equally interactive, our current, disease-by-disease approach to modeling and treating infectious diseases is inadequate (3).

  15. Risk of cancer onset in sub-Saharan Africans affected with chronic gastrointestinal parasitic diseases.

    PubMed

    Waku, M; Napolitano, L; Clementini, E; Staniscia, T; Spagnolli, C; Andama, A; Kasiriye, P; Innocenti, P

    2005-01-01

    Gastrointestinal Schistosomiasis and Amebiasis are uncommon in the western world, while such infections are frequent in the African community. In addition to the problems associated with the clinical symptoms of these parasitic infections, it is important to stress the increase in cancer of the Gastro-Intestinal (GI) tract. In this study we evaluate the prevalence of cancer in patients affected by chronic inflammatory diseases caused by the above named parasites. In three years, from January 2000 to December 2003, we observed a total of 1199 subject. Of these, 950 presented with complaints of diarrhoea, vomiting, abdominal pain, melena, hematemesis, rectal discharges and alteration of bowel habits. A total of 818 patients were evaluated in Uganda (Mulago and Arua hospitals) and 381 at Luisa Guidotti Hospital in Zimbabwe. An exhaustive clinical history was collected for each patient and then physical and laboratory examinations were performed. The clinical files of all patients previously admitted to the respective hospitals were obtained and the information taken from these files was then integrated with our clinical findings. Subjects who were found free of gastro-intestinal disease after examinations and did not have a clinical history of infective GI disease but presented with other pathologies, were regarded as control group. The control group was composed of 249 subjects. The subjects who were positive on examination underwent further investigations. The number of patients affected by schistosomiasis and amebiasis were 221 and 224 respectively. The number of patients who suffered from aspecific enterocolitis was 454, intestinal tuberculosis was present in 21 patients and we found 30 patients with esophageal candidiasis. Patients who had the above mentioned GI diseases were then divided into 3 groups. First group was composed of patients who had a clinical history of infective GI diseases and were re-admitted for similar symptoms, and on examination were

  16. Adaptive Radiation within Marine Anisakid Nematodes: A Zoogeographical Modeling of Cosmopolitan, Zoonotic Parasites

    PubMed Central

    Kuhn, Thomas; García-Màrquez, Jaime; Klimpel, Sven

    2011-01-01

    Parasites of the nematode genus Anisakis are associated with aquatic organisms. They can be found in a variety of marine hosts including whales, crustaceans, fish and cephalopods and are known to be the cause of the zoonotic disease anisakiasis, a painful inflammation of the gastro-intestinal tract caused by the accidental consumptions of infectious larvae raw or semi-raw fishery products. Since the demand on fish as dietary protein source and the export rates of seafood products in general is rapidly increasing worldwide, the knowledge about the distribution of potential foodborne human pathogens in seafood is of major significance for human health. Studies have provided evidence that a few Anisakis species can cause clinical symptoms in humans. The aim of our study was to interpolate the species range for every described Anisakis species on the basis of the existing occurrence data. We used sequence data of 373 Anisakis larvae from 30 different hosts worldwide and previously published molecular data (n = 584) from 53 field-specific publications to model the species range of Anisakis spp., using a interpolation method that combines aspects of the alpha hull interpolation algorithm as well as the conditional interpolation approach. The results of our approach strongly indicate the existence of species-specific distribution patterns of Anisakis spp. within different climate zones and oceans that are in principle congruent with those of their respective final hosts. Our results support preceding studies that propose anisakid nematodes as useful biological indicators for their final host distribution and abundance as they closely follow the trophic relationships among their successive hosts. The modeling might although be helpful for predicting the likelihood of infection in order to reduce the risk of anisakiasis cases in a given area. PMID:22180787

  17. Adaptive radiation within marine anisakid nematodes: a zoogeographical modeling of cosmopolitan, zoonotic parasites.

    PubMed

    Kuhn, Thomas; García-Màrquez, Jaime; Klimpel, Sven

    2011-01-01

    Parasites of the nematode genus Anisakis are associated with aquatic organisms. They can be found in a variety of marine hosts including whales, crustaceans, fish and cephalopods and are known to be the cause of the zoonotic disease anisakiasis, a painful inflammation of the gastro-intestinal tract caused by the accidental consumptions of infectious larvae raw or semi-raw fishery products. Since the demand on fish as dietary protein source and the export rates of seafood products in general is rapidly increasing worldwide, the knowledge about the distribution of potential foodborne human pathogens in seafood is of major significance for human health. Studies have provided evidence that a few Anisakis species can cause clinical symptoms in humans. The aim of our study was to interpolate the species range for every described Anisakis species on the basis of the existing occurrence data. We used sequence data of 373 Anisakis larvae from 30 different hosts worldwide and previously published molecular data (n = 584) from 53 field-specific publications to model the species range of Anisakis spp., using a interpolation method that combines aspects of the alpha hull interpolation algorithm as well as the conditional interpolation approach. The results of our approach strongly indicate the existence of species-specific distribution patterns of Anisakis spp. within different climate zones and oceans that are in principle congruent with those of their respective final hosts. Our results support preceding studies that propose anisakid nematodes as useful biological indicators for their final host distribution and abundance as they closely follow the trophic relationships among their successive hosts. The modeling might although be helpful for predicting the likelihood of infection in order to reduce the risk of anisakiasis cases in a given area.

  18. Parasitic Colitis

    PubMed Central

    Hechenbleikner, Elizabeth M.; McQuade, Jennifer A.

    2015-01-01

    Over one billion people worldwide harbor intestinal parasites. Parasitic intestinal infections have a predilection for developing countries due to overcrowding and poor sanitation but are also found in developed nations, such as the United States, particularly in immigrants or in the setting of sporadic outbreaks. Although the majority of people are asymptomatically colonized with parasites, the clinical presentation can range from mild abdominal discomfort or diarrhea to serious complications, such as perforation or bleeding. Protozoa and helminths (worms) are the two major classes of intestinal parasites. Protozoal intestinal infections include cryptosporidiosis, cystoisosporiasis, cyclosporiasis, balantidiasis, giardiasis, amebiasis, and Chagas disease, while helminth infections include ascariasis, trichuriasis, strongyloidiasis, enterobiasis, and schistosomiasis. Intestinal parasites are predominantly small intestine pathogens but the large intestine is also frequently involved. This article highlights important aspects of parasitic infections of the colon including epidemiology, transmission, symptoms, and diagnostic methods as well as appropriate medical and surgical treatment. PMID:26034403

  19. Dogs infected with the blood trypomastigote form of Trypanosoma cruzi display an increase expression of cytokines and chemokines plus an intense cardiac parasitism during acute infection.

    PubMed

    de Souza, Sheler Martins; Vieira, Paula Melo de Abreu; Roatt, Bruno Mendes; Reis, Levi Eduardo Soares; da Silva Fonseca, Kátia; Nogueira, Nívia Carolina; Reis, Alexandre Barbosa; Tafuri, Washington Luiz; Carneiro, Cláudia Martins

    2014-03-01

    The recent increase in immigration of people from areas endemic for Chagas disease (Trypanosoma cruzi) to the United States and Europe has raised concerns about the transmission via blood transfusion and organ transplants in these countries. Infection by these pathways occurs through blood trypomastigotes (BT), and these forms of T. cruzi are completely distinct of metacyclic trypomastigotes (MT), released by triatomine vector, in relation to parasite-host interaction. Thus, research comparing infection with these different infective forms is important for explaining the potential impacts on the disease course. Here, we investigated tissue parasitism and relative mRNA expression of cytokines, chemokines, and chemokine receptors in the heart during acute infection by MT or BT forms in dogs. BT-infected dogs presented a higher cardiac parasitism, increased relative mRNA expression of pro-inflammatory and immunomodulatory cytokines and of the chemokines CCL3/MIP-1α, CCL5/RANTES, and the chemokine receptor CCR5 during the acute phase of infection, as compared to MT-infected dogs. These results suggest that infection with BT forms may lead to an increased immune response, as revealed by the cytokines ratio, but this kind of immune response was not able to control the cardiac parasitism. Infection with the MT form presented an increase in the relative mRNA expression of IL-12p40 as compared to that of IL-10 or TGF-β1. Correlation analysis showed increased relative mRNA expression of IFN-γ as well as IL-10, which may be an immunomodulatory response, as well as an increase in the correlation of CCL5/RANTES and its CCR5 receptor. Our findings revealed a difference between inoculum sources of T. cruzi, as vectorial or transfusional routes of T. cruzi infection may trigger distinct parasite-host interactions during the acute phase, which may influence immunopathological aspects of Chagas disease.

  20. Obstetric patients in intensive care unit: Perspective from a teaching hospital in Pakistan

    PubMed Central

    Irfan Ahmed, Sheikh; Raza, Amir; Khurshid, Ayesha; Chishti, Uzma

    2016-01-01

    Objective Review of obstetric cases admitted to the intensive care unit. Design Ten year retrospective review of individual patients' medical records. Participants Records of obstetric patients admitted from 2005–2014. Setting Aga Khan University Hospital Karachi Main Outcome measures Diagnosis at the time of admission, associated risk factors, and intervention required aspects of management and rate of mortality. Findings A total of 194 obstetric patients were admitted out of which 86.2% of patients had ventilator support. Mortality was not seen to be significantly associated with parity and antenatal/postnatal status. The median age of patients was 34 years, minimum length of stay was 24 hours and maximum stay was 53 days. Sixty one percent of patients were admitted to with organ system failure. The overall mortality rate was 21.64% (42/194). The mortality rate was five times more likely in patients who had gastro-intestinal complication {Odds Ratio=4.87; 95%CI: 1.65-14.36}. The largest group of patients {28.4%} presented with hematological diagnosis. Conclusion When the intensive care unit admission became essential, primary diagnosis included: postpartum hemorrhage, hypertensive disorders, sepsis and infectious diseases. An increased vigilance of high-risk pregnant women and a stabilization of their condition before intervention is administered, improves the outcome of these women. PMID:27895930

  1. Multimodal treatment for high-risk prostate cancer with high-dose intensity-modulated radiation therapy preceded or not by radical prostatectomy, concurrent intensified-dose docetaxel and long-term androgen deprivation therapy: results of a prospective phase II trial

    PubMed Central

    2014-01-01

    Background The optimal management of high-risk prostate cancer remains uncertain. In this study we assessed the safety and efficacy of a novel multimodal treatment paradigm for high-risk prostate cancer. Methods This was a prospective phase II trial including 35 patients with newly diagnosed high-risk localized or locally advanced prostate cancer treated with high-dose intensity-modulated radiation therapy preceded or not by radical prostatectomy, concurrent intensified-dose docetaxel-based chemotherapy and long-term androgen deprivation therapy. Primary endpoint was acute and late toxicity evaluated with the Common Terminology Criteria for Adverse Events version 3.0. Secondary endpoint was biochemical and clinical recurrence-free survival explored with the Kaplan-Meier method. Results Acute gastro-intestinal and genito-urinary toxicity was grade 2 in 23% and 20% of patients, and grade 3 in 9% and 3% of patients, respectively. Acute blood/bone marrow toxicity was grade 2 in 20% of patients. No acute grade ≥4 toxicity was observed. Late gastro-intestinal and genito-urinary toxicity was grade 2 in 9% of patients each. No late grade ≥3 toxicity was observed. Median follow-up was 63 months (interquartile range 31–79). Actuarial 5-year biochemical and clinical recurrence-free survival rate was 55% (95% confidence interval, 35-75%) and 70% (95% confidence interval, 52-88%), respectively. Conclusions In our phase II trial testing a novel multimodal treatment paradigm for high-risk prostate cancer, toxicity was acceptably low and mid-term oncological outcome was good. This treatment paradigm, thus, may warrant further evaluation in phase III randomized trials. PMID:24423462

  2. Changes in prevalence and intensity of infection of Profilicollis altmani (Perry, 1942) cystacanth (Acanthocephala) parasitizing the mole crab Emerita analoga (Stimpson, 1857): an El Niño cascade effect?

    NASA Astrophysics Data System (ADS)

    Oliva, Marcelo E.; Barrios, Irene; Thatje, Sven; Laudien, Jürgen

    2008-03-01

    Prevalence and intensity changes in cystacanths of the acanthocephalan Profilicollis altmani parasitizing the mole crab Emerita analoga under El Niño (EN) and non-El Niño (non-EN) conditions are analyzed. Both, mean intensity and prevalence of infection by P. altmani differ significantly for the whole size range and for each size class of 10 mm intervals (except prevalence for size classes exceeding 18 mm carapace length) between EN (1998) and non-EN (2002) years, without observed size distribution differences in the intermediate host E. analoga under either condition. Significant difference in infestation rates of the intermediate host E. analoga is discussed as being an EN cascade effect on predators such as sea birds (i.e., Larus spp. and Calidris sp.), acting as definitive hosts of P. altmani, and which are known to decrease significantly in abundance during EN.

  3. Lineage analysis of circulating Trypanosoma cruzi parasites and their association with clinical forms of Chagas disease in Bolivia.

    PubMed

    del Puerto, Ramona; Nishizawa, Juan Eiki; Kikuchi, Mihoko; Iihoshi, Naomi; Roca, Yelin; Avilas, Cinthia; Gianella, Alberto; Lora, Javier; Velarde, Freddy Udalrico Gutierrez; Renjel, Luis Alberto; Miura, Sachio; Higo, Hiroo; Komiya, Norihiro; Maemura, Koji; Hirayama, Kenji

    2010-05-18

    The causative agent of Chagas disease, Trypanosoma cruzi, is divided into 6 Discrete Typing Units (DTU): Tc I, IIa, IIb, IIc, IId and IIe. In order to assess the relative pathogenicities of different DTUs, blood samples from three different clinical groups of chronic Chagas disease patients (indeterminate, cardiac, megacolon) from Bolivia were analyzed for their circulating parasites lineages using minicircle kinetoplast DNA polymorphism. Between 2000 and 2007, patients sent to the Centro Nacional de Enfermedades Tropicales for diagnosis of Chagas from clinics and hospitals in Santa Cruz, Bolivia, were assessed by serology, cardiology and gastro-intestinal examinations. Additionally, patients who underwent colonectomies due to Chagasic magacolon at the Hospital Universitario Japonés were also included. A total of 306 chronic Chagas patients were defined by their clinical types (81 with cardiopathy, 150 without cardiopathy, 100 with megacolon, 144 without megacolon, 164 with cardiopathy or megacolon, 73 indeterminate and 17 cases with both cardiopathy and megacolon). DNA was extracted from 10 ml of peripheral venous blood for PCR analysis. The kinetoplast minicircle DNA (kDNA) was amplified from 196 out of 306 samples (64.1%), of which 104 (53.3%) were Tc IId, 4 (2.0%) Tc I, 7 (3.6%) Tc IIb, 1 (0.5%) Tc IIe, 26 (13.3%) Tc I/IId, 1 (0.5%) Tc I/IIb/IId, 2 (1.0%) Tc IIb/d and 51 (25.9%) were unidentified. Of the 133 Tc IId samples, three different kDNA hypervariable region patterns were detected; Mn (49.6%), TPK like (48.9%) and Bug-like (1.5%). There was no significant association between Tc types and clinical manifestations of disease. None of the identified lineages or sublineages was significantly associated with any particular clinical manifestations in the chronic Chagas patients in Bolivia.

  4. Lineage Analysis of Circulating Trypanosoma cruzi Parasites and Their Association with Clinical Forms of Chagas Disease in Bolivia

    PubMed Central

    del Puerto, Ramona; Nishizawa, Juan Eiki; Kikuchi, Mihoko; Iihoshi, Naomi; Roca, Yelin; Avilas, Cinthia; Gianella, Alberto; Lora, Javier; Gutierrez Velarde, Freddy Udalrico; Renjel, Luis Alberto; Miura, Sachio; Higo, Hiroo; Komiya, Norihiro; Maemura, Koji; Hirayama, Kenji

    2010-01-01

    Background The causative agent of Chagas disease, Trypanosoma cruzi, is divided into 6 Discrete Typing Units (DTU): Tc I, IIa, IIb, IIc, IId and IIe. In order to assess the relative pathogenicities of different DTUs, blood samples from three different clinical groups of chronic Chagas disease patients (indeterminate, cardiac, megacolon) from Bolivia were analyzed for their circulating parasites lineages using minicircle kinetoplast DNA polymorphism. Methods and Findings Between 2000 and 2007, patients sent to the Centro Nacional de Enfermedades Tropicales for diagnosis of Chagas from clinics and hospitals in Santa Cruz, Bolivia, were assessed by serology, cardiology and gastro-intestinal examinations. Additionally, patients who underwent colonectomies due to Chagasic magacolon at the Hospital Universitario Japonés were also included. A total of 306 chronic Chagas patients were defined by their clinical types (81 with cardiopathy, 150 without cardiopathy, 100 with megacolon, 144 without megacolon, 164 with cardiopathy or megacolon, 73 indeterminate and 17 cases with both cardiopathy and megacolon). DNA was extracted from 10 ml of peripheral venous blood for PCR analysis. The kinetoplast minicircle DNA (kDNA) was amplified from 196 out of 306 samples (64.1%), of which 104 (53.3%) were Tc IId, 4 (2.0%) Tc I, 7 (3.6%) Tc IIb, 1 (0.5%) Tc IIe, 26 (13.3%) Tc I/IId, 1 (0.5%) Tc I/IIb/IId, 2 (1.0%) Tc IIb/d and 51 (25.9%) were unidentified. Of the 133 Tc IId samples, three different kDNA hypervariable region patterns were detected; Mn (49.6%), TPK like (48.9%) and Bug-like (1.5%). There was no significant association between Tc types and clinical manifestations of disease. Conclusions None of the identified lineages or sublineages was significantly associated with any particular clinical manifestations in the chronic Chagas patients in Bolivia. PMID:20502516

  5. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia.

    PubMed

    Sissay, Menkir M; Uggla, Arvid; Waller, Peter J

    2007-10-01

    A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger Oesopha-gostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the

  6. Prevalence and intensity of fleas parasitizing an isolated population of screaming hairy armadillo in Buenos Aires province, Argentina: host-related factors and temporal dynamics.

    PubMed

    Ezquiaga, M Cecilia; Abba, Agustín M; Cassini, Guillermo H; Lareschi, Marcela

    2017-08-25

    Fleas (Siphonaptera) of an isolated population of Chaetophractus vellerosus (Mammalia: Xenarthra) from Magdalena (Buenos Aires province) were studied, and their presence was associated with host-related factors (age, sex, weight, size, and physical condition) and temporal dynamics (seasonality and year). Three species of fleas were identified: Polygenis (Polygenis) platensis (Rhopalopsyllidae), Tunga penetrans (Tungidae), and Pulex irritans (Pulicidae). Prevalences were significant for year, season, and physical condition. Intensities were significantly different for year, physical condition, and weight. The intensities of fleas were higher in 2009 than in other years, probably because of lower rainfall than the annual average leading to extremely dry climatic conditions in 2008. Intensities decreased in individuals with major body weight and increased in individuals with poor physical condition. In this study, the dynamics of the flea community associated with an armadillo population is analyzed for the first time taking into account host-related factors and temporal dynamics, and also how these factors influence the community.

  7. Parasitic Apologies

    ERIC Educational Resources Information Center

    Galatolo, Renata; Ursi, Biagio; Bongelli, Ramona

    2016-01-01

    The action of apologizing can be accomplished as the main business of the interaction or incidentally while participants are doing something else. We refer to these apologies as "parasitic apologies," because they are produced "en passant" (Schegloff, 2007), and focus our analysis on this type of apology occurring at the…

  8. Parasites: Water

    MedlinePlus

    ... water, they can spread the parasite into the water and continue the cycle of contamination and infection. Schistosomiasis can be spread when people swim in or have contact with freshwater lakes that are contaminated with ... drinking water or recreational water. Individuals spending time in the ...

  9. Foodborne Parasites

    USDA-ARS?s Scientific Manuscript database

    Foodborne infections are a significant cause of morbidity and mortality worldwide, and foodborne parasitic diseases, though not as widespread as bacterial and viral infections, are common on all continents and in most ecosystems, including arctic, temperate, and tropical regions. Certain foodborne ...

  10. Parasitic castration: the evolution and ecology of body snatchers

    USGS Publications Warehouse

    Lafferty, Kevin D.; Kuris, Armand M.

    2009-01-01

    Castration is a response to the tradeoff between consumption and longevity faced by parasites. Common parasitic castrators include larval trematodes in snails, and isopod and barnacle parasites of crustaceans. The infected host (with its many unique properties) is the extended phenotype of the parasitic castrator. Because an individual parasitic castrator can usurp all the reproductive energy from a host, and that energy is limited, intra- and interspecific competition among castrators is generally intense. These parasites can be abundant and can substantially depress host density. Host populations subject to high rates of parasitic castration appear to respond by maturing more rapidly.

  11. Behavioural trade-offs in response to external stimuli: time allocation of an Arctic ungulate during varying intensities of harassment by parasitic flies.

    PubMed

    Witter, Leslie A; Johnson, Chris J; Croft, Bruno; Gunn, Anne; Gillingham, Michael P

    2012-01-01

    1. Macroparasites may be a major factor shaping animal behaviour. Tundra ecosystems inhabited by caribou and reindeer (Rangifer tarandus) are known for large concentrations of ectoparasites including mosquitoes (Culicidae) and black flies (Simuliidae), as well as endoparasitic oestrid flies (Oestridae). 2. Increased intensity and duration of insect harassment because of climatic warming is hypothesized as a potential factor in recent declines of Rangifer across the circumpolar north. Although there is a well-observed relationship between insect harassment and caribou/reindeer behaviour, the influence of ecto- relative to endoparasitic species is unclear. Climatic changes may favour the activity patterns, distribution or abundance of certain insect species; thus, understanding differential effects on the behaviour of Rangifer is important. 3. We recorded caribou behaviour using group scan and focal sampling methods, while simultaneously trapping insects and recording weather conditions on the postcalving/summer range of the Bathurst barren-ground caribou herd in Northwest Territories and Nunavut, Canada, during 2007-2009. 4. We developed statistical model sets representing hypotheses about the effects of insects, weather, habitat/location, and date/time on caribou behaviour. We used multinomial logistic regression models to explore factors affecting the relative dominance of behaviour types within groups of caribou and fractional multinomial logistic regression models to determine factors influencing time allocation by individual caribou. We examined changes in feeding intensity using fractional logistic regression. 5. Relative dominance of insect avoidance behaviour within caribou groups and time allocation to insect avoidance by individual caribou increased when oestrid flies were present or black flies were active at moderate-high levels. Mosquito activity had relatively little effect on caribou behaviour. Time spent feeding was reduced by the greatest degree

  12. Carotenoid-based bill colour is an integrative signal of multiple parasite infection in blackbird

    NASA Astrophysics Data System (ADS)

    Biard, Clotilde; Saulnier, Nicolas; Gaillard, Maria; Moreau, Jérôme

    2010-11-01

    In the study of parasite-mediated sexual selection, there has been controversial evidence for the prediction that brighter males should have fewer parasites. Most of these studies have focused on one parasite species. Our aim was to investigate the expression of carotenoid-based coloured signals in relation to patterns of multiple parasite infections, to determine whether colour reflects parasite load of all parasite species, or whether different relationships might be found when looking at each parasite species independently. We investigated the relationship between bill colour, body mass and plasma carotenoids and parasite load (feather chewing lice, blood parasite Plasmodium sp., intestinal parasites cestodes and coccidia) in the blackbird ( Turdus merula). Bill colour on its own appeared to be a poor predictor of parasite load when investigating its relationships with individual parasite species. Variation in parasite intensities at the community level was summarised using principal component analysis to derive synthetic indexes of relative parasite species abundance and absolute parasite load. The relative abundance of parasite species was strongly related to bill colour, plasma carotenoid levels and body mass: birds with relatively more cestodes and chewing lice and relatively less Plasmodium and coccidia had a more colourful bill, circulated more carotenoids and were heavier. These results suggest that bill colour more accurately reflects the relative intensities of parasite infection, rather than one-by-one relationships with parasites or absolute parasite burden. Investigating patterns of multiple parasite infection would thus improve our understanding of the information conveyed by coloured signals on parasite load.

  13. Gross anatomy of the ringed seal (Pusa hispida) gastro-intestinal tract.

    PubMed

    Smodlaka, H; Henry, R W

    2014-06-01

    The gross anatomical structure of the ringed seal (Pusa hispida) gastrointestinal tract is poorly described and often veterinary anatomical terminology is not used. Although the basic abdominal visceral pattern corresponded to domestic carnivores, significant differences were noted. The stomach was an elongated sharply bent tube (u-shaped) with the pylorus and fundus juxtaposed. The elongated jejunum measured up to 15.6 times body length and had 37 jejunal arteries from the cranial mesenteric artery. The pancreas was asymmetrical with a small right lobe and a large left lobe. The unusually short greater omentum negated formation of deep and superficial leaves. The most remarkable difference was the separation of the liver parenchyma into three physically separate masses, held together by hepatic ducts, veins and arteries. The topography and position of the liver was dependent on the amount of blood in the hepatic sinus (distended hepatic veins and hepatic portion of vena cava). Thus, as the hepatic sinus filled, the lateral liver masses separate from the central mass by moving caudolaterally. This was facilitated by modified coronary and triangular ligaments which did not attach directly to the liver, but instead to the hepatic sinus. These anatomical adaptations are apparently advantageous to ringed seal's survival in a deep marine environment. © 2013 Blackwell Verlag GmbH.

  14. Identifying the Ion Channels Responsible for Signaling Gastro-Intestinal Based Pain

    PubMed Central

    Brierley, Stuart M.; Hughes, Patrick A.; Harrington, Andrea M.; Rychkov, Grigori Y.; Blackshaw, L. Ashley

    2010-01-01

    We are normally unaware of the complex signalling events which continuously occur within our internal organs. Most of us only become cognisant when sensations of hunger, fullness, urgency or gas arise. However, for patients with organic and functional bowel disorders pain is an unpleasant and often debilitating reminder. Furthermore, chronic pain still represents a large unmet need for clinical treatment. Consequently, chronic pain has a considerable economic impact on health care systems and the afflicted individuals. In order to address this need we must understand how symptoms are generated within the gut, the molecular pathways responsible for generating these signals and how this process changes in disease states. PMID:27713376

  15. Effect of antiorthostatic BedRest (BR) on GastroIntestinal Motility (GIM) of normal subjects

    NASA Technical Reports Server (NTRS)

    Putcha, L.; Hunter, R. P.; Tietze, K. J.; Cintron, N. M.

    1992-01-01

    The combined effects of postural changes, fluid shifts and diuresis associated with the absence of the gravity vector may decrease gastrointestinal motility (GIM) during space flight. GIM can be estimated from the mouth to cecum transit time (MCTT) of orally administered lactulose (LAC); this test is used to assess changes in GIM in normal subjects and in patients with GI pathology and related disease conditions. Since bedrest (BR) mimics some of the physiological changes that occur during space flight, the effect of ten days of BR on GIM was evaluated from the MCTT of LAC. Methods: Subjects were 12 nonsmoking males between the ages of 35 and 50. After an 8-10 hour fast, subjects ingested Cephulac (registered) (20 g solution) with a low-fiber breakfast on four different days (45, 30, 25, and 20) before BR and on three separate days (4, 7, and 10) during BR. Breath-H2 concentrations were measured before and at 10 minute intervals for 4 hours after breakfast using a Quintron breathalyzer and MCTT was determined from these data. Results: MCTT ranged between 10 and 122 minutes during ambulation and 80 to 120 minutes during BR with means of 79 minutes and 122 minutes respectively. Conclusion: Mean MCTT during BR was 54 percent longer than during ambulation, suggesting that absorption and availability of orally administered medications and nutrients may be delayed or impaired as a result of decreased GIM during bedrest.

  16. Drinking Water Quality and the Geospatial Distribution of Notified Gastro-Intestinal Infections.

    PubMed

    Grilc, Eva; Gale, Ivanka; Veršič, Aleš; Žagar, Tina; Sočan, Maja

    2015-09-01

    Even brief episodes of fecal contamination of drinking water can lead directly to illness in the consumers. In water-borne outbreaks, the connection between poor microbial water quality and disease can be quickly identified. The impact of non-compliant drinking water samples due to E. coli taken for regular monitoring on the incidence of notified acute gastrointestinal infections has not yet been studied. The objective of this study was to analyse the geographical distribution of notified acute gastrointestinal infections (AGI) in Slovenia in 2010, with hotspot identification. The second aim of the study was to correlate the fecal contamination of water supply system on the settlement level with the distribution of notified AGI cases. Spatial analysis using geo-information technology and other methods were used. Hot spots with the highest proportion of notified AGI cases were mainly identified in areas with small supply zones. The risk for getting AGI was drinking water contaminated with E. coli from supply zones with 50-1000 users: RR was 1.25 and significantly greater than one (p-value less than 0.001). This study showed the correlation between the frequency of notified AGI cases and non-compliant results in drinking water monitoring.

  17. Gastro-intestinal toxicity of chemotherapeutics in colorectal cancer: The role of inflammation

    PubMed Central

    Lee, Chun Seng; Ryan, Elizabeth J; Doherty, Glen A

    2014-01-01

    Chemotherapy-induced diarrhea (CID) is a common and often severe side effect experienced by colorectal cancer (CRC) patients during their treatment. As chemotherapy regimens evolve to include more efficacious agents, CID is increasingly becoming a major cause of dose limiting toxicity and merits further investigation. Inflammation is a key factor behind gastrointestinal (GI) toxicity of chemotherapy. Different chemotherapeutic agents activate a diverse range of pro-inflammatory pathways culminating in distinct histopathological changes in the small intestine and colonic mucosa. Here we review the current understanding of the mechanisms behind GI toxicity and the mucositis associated with systemic treatment of CRC. Insights into the inflammatory response activated during this process gained from various models of GI toxicity are discussed. The inflammatory processes contributing to the GI toxicity of chemotherapeutic agents are increasingly being recognised as having an important role in the development of anti-tumor immunity, thus conferring added benefit against tumor recurrence and improving patient survival. We review the basic mechanisms involved in the promotion of immunogenic cell death and its relevance in the treatment of colorectal cancer. Finally, the impact of CID on patient outcomes and therapeutic strategies to prevent or minimise the effect of GI toxicity and mucositis are discussed. PMID:24744571

  18. Long-term exposure to zero-g and the gastro-intestinal tract function

    NASA Technical Reports Server (NTRS)

    Mccormack, Percial D.

    1989-01-01

    The gastrointestinal tract (GIT) function is described with emphasis placed on its important role to smooth, delay, and modify sudden fluid load stress applied to the fluid distribution control system in the body. Two basic components of the GIT are considered: stomach dynamics, which involves storage, mixing, and discharge of food into the intestine after addition of gastric juices; and absorption of water and electrolytes from the small intestine. A dynamic model of these components is described, along with performance characteristics computed consecutively for one g and zero g conditions. The main impact of the zero g condition appears to be through a change in osmotic driven transport across the gut wall. A dramatic change in transport characteristics is predicted with implication for many body systems (the immune system in particular) during long-term exposure to zero g. Experimental measurements in zero g are needed to evaluate these predictions.

  19. Use of T-Tube Enterostomy in Neonatal Gastro-intestinal Surgery.

    PubMed

    Al-Zaiem, Maher; Al-Garni, Abdulhai F; Al-Maghrebi, Abdulrahman; Asghar, Asim A

    2016-01-01

    Aim: To evaluate the results of the use of the T-tube ileostomy in neonatal intestinal surgery cases. Materials and Methods: A retrospective review of sixty two neonates underwent intestinal obstruction surgery by using T-tube ileostomy was conducted between January 1990 and January 2013.The pathologies of the intestinal obstruction were; thirty four of jejunoileal atresia cases, thirteen case meconium ileus, eight cases perforated necrotizing enterocolitis (NEC), three cases meconium peritonitis, three cases with bowel resection due to intestinal volvulus, and one case of gastroschisis. Results: Mean duration of T-tube placement was 13 days (range9-20days) and the sites of T-tube insertion closed spontaneously in 2 days (range 1-4 days). The mean duration for starting oral intake postoperatively in these patients was 9 days (6-16 days). All patients well tolerated the procedure and there were no serious complications related to the T-tube insertion. However, four patients died due to other reasons like sepsis, respiratory failure and prematurity. Conclusion: T-tube enterostomy is an effective and safe technique for treatment of selected cases of neonatal intestinal surgery. It showed less morbidity and mortality rates than the conventional stoma. Therefore, it is considered a helpful approach in cases where there is danger of hypoperistaltic dilated bowel proximal to the anastomosis.

  20. Functional changes with feeding in the gastro-intestinal epithelia of the Burmese python (Python molurus).

    PubMed

    Helmstetter, Cécile; Reix, Nathalie; T'Flachebba, Mathieu; Pope, Robert K; Secor, Stephen M; Le Maho, Yvon; Lignot, Jean-Hervé

    2009-09-01

    The morphology of the digestive system in fasting and refed Burmese pythons was determined, as well as the localization of the proton (H(+), K(+)-ATPase) and sodium (Na(+), K(+)-ATPase) pumps. In fasting pythons, oxyntopeptic cells located within the fundic glands are typically non-active, with a thick apical tubulovesicular system and numerous zymogen granules. They become active Immediately after feeding but return to a non-active state 3 days after the Ingestion of the prey. The proton pump, expressed throughout the different fasting/feeding states, is either sequestered in the tubulovesicular system in non-active cells or located along the apical digitations extending within the crypt lumen in active cells. The sodium pump is rapidly upregulated in fed animals and is classically located along the baso-lateral membranes of the gastric oxyntopeptic cells. In the Intestine, it is only expressed along the lateral membranes of the enterocytes, i.e., above the lateral spaces and not along the basal side of the cells. Thus, solute transport within the Intestinal lining is mainly achieved through the apical part of the cells and across the lateral spaces while absorbed fat massively crosses the entire height of the cells and flows into the Intercellular spaces. Therefore, in the Burmese python, the gastrointestinal cellular system quickly upregulates after feeding, due to Inexpensive cellular changes, passive mechanisms, and the progressive activation and synthesis of key enzymes such as the sodium pump. This cell plasticity also allows anticipation of the next fasting and feeding periods.

  1. Mechanisms and kinetics of tryptophan N-nitrosation in a gastro-intestinal model.

    PubMed

    de La Pomélie, Diane; Santé-Lhoutellier, Véronique; Gatellier, Philippe

    2017-03-01

    The reaction of nitrite with different amino acids containing secondary amino groups was tested under simulated in-vitro conditions of the digestive tract. After treatment, tryptophan was the only amino acid that exhibited specific UV absorbance of nitrosamines at 335nm, supporting the assumption that it is the main source of endogenous nitrosamines. The combined effect of pH (from 2 to 6.5) and nitrite (from 0.1 to 20mM) was analyzed and the mechanisms and kinetic laws of tryptophan N-nitrosation were determined. The model was then completed by the addition of iron and various antioxidants in concentrations reflecting different diets. The results clearly demonstrated that, in the presence of iron, large amounts of N-nitroso-tryptophan can be formed even at neutral pH, as in the intestine. Antioxidants (ascorbic acid, trolox C, β carotene, chlorogenic acid, phytic acid and butylated-hydroxytoluene) had various impacts on the extent of N-nitrosation, depending on the iron level.

  2. Morphoelastic control of gastro-intestinal organogenesis: Theoretical predictions and numerical insights

    NASA Astrophysics Data System (ADS)

    Balbi, V.; Kuhl, E.; Ciarletta, P.

    2015-05-01

    With nine meters in length, the gastrointestinal tract is not only our longest, but also our structurally most diverse organ. During embryonic development, it evolves as a bilayered tube with an inner endodermal lining and an outer mesodermal layer. Its inner surface displays a wide variety of morphological patterns, which are closely correlated to digestive function. However, the evolution of these intestinal patterns remains poorly understood. Here we show that geometric and mechanical factors can explain intestinal pattern formation. Using the nonlinear field theories of mechanics, we model surface morphogenesis as the instability problem of constrained differential growth. To allow for internal and external expansion, we model the gastrointestinal tract with homogeneous Neumann boundary conditions. To establish estimates for the folding pattern at the onset of folding, we perform a linear stability analysis supplemented by the perturbation theory. To predict pattern evolution in the post-buckling regime, we perform a series of nonlinear finite element simulations. Our model explains why longitudinal folds emerge in the esophagus with a thick and stiff outer layer, whereas circumferential folds emerge in the jejunum with a thinner and softer outer layer. In intermediate regions like the feline esophagus, longitudinal and circumferential folds emerge simultaneously. Our model could serve as a valuable tool to explain and predict alterations in esophageal morphology as a result of developmental disorders or certain digestive pathologies including food allergies.

  3. Bloating and functional gastro-intestinal disorders: Where are we and where are we going?

    PubMed Central

    Iovino, Paola; Bucci, Cristina; Tremolaterra, Fabrizio; Santonicola, Antonella; Chiarioni, Giuseppe

    2014-01-01

    Bloating is one of the most common and bothersome symptoms complained by a large proportion of patients. This symptom has been described with various definitions, such as sensation of a distended abdomen or an abdominal tension or even excessive gas in the abdomen, although bloating should probably be defined as the feeling (e.g. a subjective sensation) of increased pressure within the abdomen. It is usually associated with functional gastrointestinal disorders, like irritable bowel syndrome, but when bloating is not part of another functional bowel or gastrointestinal disorder it is included as an independent entity in Rome III criteria named functional bloating. In terms of diagnosis, major difficulties are due to the lack of measurable parameters to assess and grade this symptom. In addition, it is still unclear to what extent the individual patient complaint of subjective bloating correlates with the objective evidence of abdominal distension. In fact, despite its clinical, social and economic relevance, bloating lacks a clear pathophysiology explanation, and an effective management endorsement, turning this common symptom into a true challenge for both patients and clinicians. Different theories on bloating etiology call into questions an increased luminal contents (gas, stools, liquid or fat) and/or an impaired abdominal empting and/or an altered intra-abdominal volume displacement (abdomino-phrenic theory) and/or an increased perception of intestinal stimuli with a subsequent use of empirical treatments (diet modifications, antibiotics and/or probiotics, prokinetic drugs, antispasmodics, gas reducing agents and tricyclic antidepressants). In this review, our aim was to review the latest knowledge on bloating physiopathology and therapeutic options trying to shed lights on those processes where a clinician could intervene to modify disease course. PMID:25339827

  4. Calcium intake and 28-year gastro-intestinal cancer mortality in Dutch civil servants.

    PubMed

    Slob, I C; Lambregts, J L; Schuit, A J; Kok, F J

    1993-04-22

    The association between calcium intake and gastrointestinal cancer mortality was investigated in a 28-year follow-up study. Data were obtained from a general health examination in 1953-1954 among Dutch civil servants and their spouses, aged 40 to 65 years. Information from 2,591 participants was used for this study. Risk analyses were performed using logistic regression models with the highest quintile of calcium intake as reference. No statistically significant relation between calcium intake and gastrointestinal cancer mortality is observed, although the risk estimate for women with the lowest calcium intake is substantial. Odds ratios (OR) were adjusted for age, energy intake and dietary fiber. After inclusion of other potential confounders to the models (body-mass index and smoking habits), the results hardly differed. Both men and women who died of colorectal cancer had a lower mean calcium intake compared to the rest of the population. For women this was statistically significant. Our results suggest that a low calcium intake may be related to gastrointestinal cancer mortality among women of this study population.

  5. Frequency and risk factors of functional gastro-intestinal disorders in a rural Indian population.

    PubMed

    Ghoshal, Uday C; Singh, Rajan

    2017-02-01

    As best estimates on functional gastrointestinal disorders (FGIDs) prevalence are expected from community studies, which are scanty from Asia, we evaluated the prevalence and risk factors of FGIDs in a rural Indian community. House-to-house survey was undertaken by trained interviewers using translated-validated Rome III and hospital anxiety and depression questionnaires. Among 3426 subjects ≥ 18 years old from 3 villages in Uttar Pradesh, 84% participated, of whom 80% were finally analyzed. Of these 2774 subjects (age 38.4 ± 16.5 years, 1573 [56.7%] male), 2654 [95.7%] were vegetarian and 120 [4.3%] non-vegetarian. Socioeconomic classes were upper (16.7%), upper middle (15.1%), lower middle (22%), upper lower (22.2%), and lower (24%) using Prasad's Classification; 603 (21.7%) had FGIDs (413 [14.9%] dyspepsia, 75 [2.7%] irritable bowel syndrome (IBS) and 115 [4.1%] dyspepsia-IBS overlap), by Rome III criteria. In subjects with dyspepsia, 49/528 (9%) had epigastric pain, 141 (27%) postprandial distress syndromes (EPS, PDS) and 338 (64%) EPS-PDS overlap. IBS was more often diarrhea than constipation-predominant subtype. On univariate analysis, chewing tobacco, aerated drink, tea/coffee, disturbed sleep, vegetarianism, and anxiety parameters and presence of dyspepsia predicting occurrence of IBS were associated with FGIDs. On multivariate analysis, chewing tobacco, aerated soft drink, tea/coffee, vegetarianism, anxiety parameters, and presence of dyspepsia predicting IBS were significant. Functional gastrointestinal disorders, particularly dyspepsia-IBS overlap, are common in rural Indian population; the risk factors included chewing tobacco, aerated soft drink, tea/coffee, vegetarian diet, disturbed sleep, anxiety, and dyspepsia predicting occurrence of IBS. © 2016 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

  6. Application Of Endoscopic Lasers For Operations In Gastro-Intestinal Tract

    NASA Astrophysics Data System (ADS)

    Skobelkin, O. K.; Saphronov, A. M.; Shapovalov, A. M.; Zaharov, P. I.

    1988-06-01

    We have described our experience in the application of high energy argon and Nd:YAG lasers for endoscopic surgical manipulations. Laser was used for the removal of polyps with a wide base, villi tumours in colon, for the elimination of scar strictures in colon anastomosis, for the formation of primary-delayed colon anastomosis and for the removal of timoral stenosis in esophagus and in colon. Laser therapy has certain advantages over other endoscopic manipulations: long-term and immediate results are better. One can use this therapy in combination with others (radial therapy, surgical treatment). We have worked out a classification of polyps and stenosing tumours in the digestive system to determine indications for laser endoscopy and to choose the best parameters of laser irradiation.

  7. [Gastroduodenal system state and levels of gastro-intestinal peptides in workers exposed to fluor compounds].

    PubMed

    Fedorov, A A; Gromov, A S

    2007-01-01

    Studies in 45 cryolite production workers (facing chronic gastritis and gastroduodenitis) demonstrated that the diseases in them have moderate inflammatory activity, atrophy of gastric lining contaminated with Helicobacter pylori, hypergastrine mia, hypopancreozymine mia and hyposecretine mia in half of the examinees.

  8. Drinking Water Quality and the Geospatial Distribution of Notified Gastro-Intestinal Infections

    PubMed Central

    GRILC, Eva; GALE, Ivanka; VERŠIČ, Aleš; ŽAGAR, Tina; SOČAN, Maja

    2015-01-01

    Introduction Even brief episodes of fecal contamination of drinking water can lead directly to illness in the consumers. In water-borne outbreaks, the connection between poor microbial water quality and disease can be quickly identified. The impact of non-compliant drinking water samples due to E. coli taken for regular monitoring on the incidence of notified acute gastrointestinal infections has not yet been studied. Methods The objective of this study was to analyse the geographical distribution of notified acute gastrointestinal infections (AGI) in Slovenia in 2010, with hotspot identification. The second aim of the study was to correlate the fecal contamination of water supply system on the settlement level with the distribution of notified AGI cases. Spatial analysis using geo-information technology and other methods were used. Results Hot spots with the highest proportion of notified AGI cases were mainly identified in areas with small supply zones. The risk for getting AGI was drinking water contaminated with E. coli from supply zones with 50–1000 users: RR was 1.25 and significantly greater than one (p-value less than 0.001). Conclusion This study showed the correlation between the frequency of notified AGI cases and non-compliant results in drinking water monitoring. PMID:27646727

  9. The emerging role of Slit-Robo pathway in gastric and other gastro intestinal cancers.

    PubMed

    Huang, Tingting; Kang, Wei; Cheng, Alfred S L; Yu, Jun; To, Ka Fai

    2015-12-16

    Gastric cancer remains one of the most common cancers worldwide and one of the leading cause for cancer-related deaths. Due to the high frequency of metastasis, it is still one of the most lethal malignancies in which kinds of signaling pathways are involved in. The Roundabout (ROBO) receptors and their secreted SLIT glycoprotein ligands, which were originally identified as important axon guidance molecules, have implication in the regulation of neurons and glia, leukocytes, and endothelial cells migration. Recent researches also put high emphasis on the important roles of the Slit-Robo pathway in tumorigenesis, cancer progression and metastasis. Herein we provide a comprehensive review on the role of these molecules and their associated signaling pathway in gastric and other gastrointestinal cancers. Improved knowledge of the Slit-Robo signaling pathway in gastric carcinoma will be useful for deep understanding the mechanisms of tumor development and identifying ideal targets of anticancer therapy in gastric carcinoma.

  10. Parasite infection and host group size: a meta-analytical review.

    PubMed

    Patterson, Jesse E H; Ruckstuhl, Kathreen E

    2013-06-01

    Many studies have identified various host behavioural and ecological traits that are associated with parasite infection, including host gregariousness. By use of meta-analyses, we investigated to what degree parasite prevalence, intensity and species richness are correlated with group size in gregarious species. We predicted that larger groups would have more parasites and higher parasite species richness. We analysed a total of 70 correlations on parasite prevalence, intensity and species richness across different host group sizes. Parasite intensity and prevalence both increased positively with group size, as expected. No significant relationships were found between host group size and parasite species richness, suggesting that larger groups do not harbour more rare or novel parasite species than smaller groups. We further predicted that the mobility of the host (mobile, sedentary) and the mode of parasite transmission (direct, indirect, mobile) would be important predictors of the effects of group sizes on parasite infection. It was found that group size was positively correlated with the prevalence and intensity of directly and indirectly transmitted parasites. However, a negative relationship was observed between group size and mobile parasite intensity, with larger groups having lower parasite intensities. Further, intensities of parasites did not increase with group size of mobile hosts, suggesting that host mobility may negate parasite infection risk. The implications for the evolution and maintenance of sociality in host species are discussed, and future research directions are highlighted.

  11. Parasite specialization in a unique habitat: hummingbirds as reservoirs of generalist blood parasites of Andean birds.

    PubMed

    Moens, Michaël A J; Valkiūnas, Gediminas; Paca, Anahi; Bonaccorso, Elisa; Aguirre, Nikolay; Pérez-Tris, Javier

    2016-09-01

    Understanding how parasites fill their ecological niches requires information on the processes involved in the colonization and exploitation of unique host species. Switching to hosts with atypical attributes may favour generalists broadening their niches or may promote specialization and parasite diversification as the consequence. We analysed which blood parasites have successfully colonized hummingbirds, and how they have evolved to exploit such a unique habitat. We specifically asked (i) whether the assemblage of Haemoproteus parasites of hummingbirds is the result of single or multiple colonization events, (ii) to what extent these parasites are specialized in hummingbirds or shared with other birds and (iii) how hummingbirds contribute to sustain the populations of these parasites, in terms of both prevalence and infection intensity. We sampled 169 hummingbirds of 19 species along an elevation gradient in Southern Ecuador to analyse the host specificity, diversity and infection intensity of Haemoproteus by molecular and microscopy techniques. In addition, 736 birds of 112 species were analysed to explore whether hummingbird parasites are shared with other birds. Hummingbirds hosted a phylogenetically diverse assemblage of generalist Haemoproteus lineages shared with other host orders. Among these parasites, Haemoproteus witti stood out as the most generalized. Interestingly, we found that infection intensities of this parasite were extremely low in passerines (with no detectable gametocytes), but very high in hummingbirds, with many gametocytes seen. Moreover, infection intensities of H. witti were positively correlated with the prevalence across host species. Our results show that hummingbirds have been colonized by generalist Haemoproteus lineages on multiple occasions. However, one of these generalist parasites (H. witti) seems to be highly dependent on hummingbirds, which arise as the most relevant reservoirs in terms of both prevalence and

  12. The many roads to parasitism: a tale of convergence.

    PubMed

    Poulin, Robert

    2011-01-01

    Parasitic organisms account for a large portion of living species. They have arisen on multiple independent occasions in many phyla, and thus encompass a huge biological diversity. This review uses several lines of evidence to argue that this vast diversity can be reduced to a few evolutionary end points that transcend phylogenetic boundaries. These represent peaks in the adaptive landscape reached independently by different lineages undergoing convergent evolution. Among eukaryotic parasites living in or on animals, six basic parasitic strategies are identified based on the number of hosts used per parasite generation, the fitness loss incurred by the host, and the transmission routes used by the parasites. They are parasitoids, parasitic castrators, directly transmitted parasites, trophically transmitted parasites, vector-transmitted parasites and micropredators. These show evidence of convergence in morphology, physiology, reproduction, life cycles and transmission patterns. Parasite-host body size ratios, and the relationship between virulence and intensity of infection, are also associated with the different parasitic strategies, but not consistently so. At the population level, patterns of parasite distribution among hosts are not uniform across all parasitic strategies, but are distinctly different for parasitoids and castrators than for other parasites. To demonstrate that the above six strategies defined for animal parasites are universal, comparisons are made with parasites of plants, in particular, plant-parasitic nematodes and parasitic angiosperms; these are shown to follow the same evolutionary trajectories seen among animal parasites, despite huge physiological and ecological differences between animals and plants. Beyond demonstrating the inevitable convergence of disparate lineages across biological hyperspace towards a limited set of adaptive strategies, this synthesis also provides a unifying framework for the study of parasitism. Copyright

  13. Protozoan Parasites.

    PubMed

    Custodio, Haidee

    2016-02-01

    • Stool antigen detection for Cryptosporidium sp, Giardia lamblia and Entamoeba histolytica are now commercially available, have better sensitivity and specificity than the traditional stool microscopy, and are less dependent on personnel skill. Tests employing newer techniques with faster turnaround time are also available for diagnosing trichomoniasis.• Nitazoxanide, the only U.S. Food and Drug Administration-approved medication for therapy of cryptosporidiosis, is effective among immunocompetent patients. However, on the basis of strong evidence from multiple clinical trials, nitazoxanide is considered ineffective among immunocompromised patients. (14) • Giardiasis can be asymptomatic or have a chronic course leading to malabsorption and failure to thrive. It can be treated with metronidazole, tinidazole, or nitazoxanide. On the basis of growing observational studies, postinfectious and extraintestinal manifestations of giardiasis occur, but the mechanisms are unclear. Given the high prevalence of giardiasis, public health implications need to be defined. (16) • Eradicating E histolytica from the gastrointestinal tract requires only intraluminal agent therapy. Therapy for invasive illnesses requires use of imidazole followed by intraluminal agents to eliminate persistent intraluminal parasites. • Malaria is considered the most lethal parasitic infection, with Plasmodium falciparum as the predominant cause of mortality. P vivax and P ovale can be dormant in the liver, and primaquine is necessary to resolve infection by P vivax and P ovale. • Among immunocompetent patients, infection with Toxoplasma gondii may be asymptomatic, involve localized lymphadenopathy, or cause ocular infection. In immunocompromised patients, reactivation or severe infection is not uncommon. On the basis of limited observational studies (there are no well-controlled randomized trials), therapy is recommended for acute infection during pregnancy to prevent transmission to the

  14. Equine immunity to parasites.

    PubMed

    Klei, T R

    2000-04-01

    Helminths are among the most significant parasites of horses in developed countries. This article examines immune responses against helminth parasites and the implications that immunologic investigations have on vaccine development, improvement of diagnostic procedures, and disease eradication.

  15. Intestinal parasitic infection.

    PubMed

    Park, Mi-Suk; Kim, Ki Whang; Ha, Hyun Kwon; Lee, Dong Ho

    2008-01-01

    In general, gastrointestinal tract is the primary involvement site of parasites during their life cycle. In this article, we will describe amebiasis, ascariasis, and anisakiasis among the many common intestinal parasitic diseases. We will review the epidemiology, life cycles, clinical manifestations and complications, and illustrate detailed imaging findings of intestinal parasites. Recognizing features of parasitic infection is important to establish an early diagnosis that leads to prompt treatment and helps avoid unnecessary surgery.

  16. Parasites, Plants, and People.

    PubMed

    Johnson, Marion; Moore, Tony

    2016-06-01

    Anthelminthic resistance is acknowledged worldwide and is a major problem in Aotearoa New Zealand, thus alternative parasite management strategies are imperative. One Health is an initiative linking animal, human, and environmental health. Parasites, plants, and people illustrate the possibilities of providing diverse diets for stock thereby lowering parasite burdens, improving the cultural wellbeing of a local community, and protecting the environment.

  17. Brood parasite eggs enhance egg survivorship in a multiply parasitized host.

    PubMed

    Gloag, Ros; Fiorini, Vanina D; Reboreda, Juan C; Kacelnik, Alex

    2012-05-07

    Despite the costs to avian parents of rearing brood parasitic offspring, many species do not reject foreign eggs from their nests. We show that where multiple parasitism occurs, rejection itself can be costly, by increasing the risk of host egg loss during subsequent parasite attacks. Chalk-browed mockingbirds (Mimus saturninus) are heavily parasitized by shiny cowbirds (Molothrus bonariensis), which also puncture eggs in host nests. Mockingbirds struggle to prevent cowbirds puncturing and laying, but seldom remove cowbird eggs once laid. We filmed cowbird visits to nests with manipulated clutch compositions and found that mockingbird eggs were more likely to escape puncture the more cowbird eggs accompanied them in the clutch. A Monte Carlo simulation of this 'dilution effect', comparing virtual hosts that systematically either reject or accept parasite eggs, shows that acceptors enjoy higher egg survivorship than rejecters in host populations where multiple parasitism occurs. For mockingbirds or other hosts in which host nestlings fare well in parasitized broods, this benefit might be sufficient to offset the fitness cost of rearing parasite chicks, making egg acceptance evolutionarily stable. Thus, counterintuitively, high intensities of parasitism might decrease or even reverse selection pressure for host defence via egg rejection.

  18. Brood parasite eggs enhance egg survivorship in a multiply parasitized host

    PubMed Central

    Gloag, Ros; Fiorini, Vanina D.; Reboreda, Juan C.; Kacelnik, Alex

    2012-01-01

    Despite the costs to avian parents of rearing brood parasitic offspring, many species do not reject foreign eggs from their nests. We show that where multiple parasitism occurs, rejection itself can be costly, by increasing the risk of host egg loss during subsequent parasite attacks. Chalk-browed mockingbirds (Mimus saturninus) are heavily parasitized by shiny cowbirds (Molothrus bonariensis), which also puncture eggs in host nests. Mockingbirds struggle to prevent cowbirds puncturing and laying, but seldom remove cowbird eggs once laid. We filmed cowbird visits to nests with manipulated clutch compositions and found that mockingbird eggs were more likely to escape puncture the more cowbird eggs accompanied them in the clutch. A Monte Carlo simulation of this ‘dilution effect’, comparing virtual hosts that systematically either reject or accept parasite eggs, shows that acceptors enjoy higher egg survivorship than rejecters in host populations where multiple parasitism occurs. For mockingbirds or other hosts in which host nestlings fare well in parasitized broods, this benefit might be sufficient to offset the fitness cost of rearing parasite chicks, making egg acceptance evolutionarily stable. Thus, counterintuitively, high intensities of parasitism might decrease or even reverse selection pressure for host defence via egg rejection. PMID:22158956

  19. Parasite fauna of farmed Nile tilapia (Oreochromis niloticus) and African catfish (Clarias gariepinus) in Uganda.

    PubMed

    Akoll, Peter; Konecny, Robert; Mwanja, Wilson W; Nattabi, Juliet K; Agoe, Catherine; Schiemer, Fritz

    2012-01-01

    An intensive parasite survey was conducted in 2008 to better understand the parasite fauna occurrence, distribution and diversity in the commercial aquaculture fish species in Uganda. A total of 265 fish collected from hatcheries and grow-out systems were examined for parasites using routine parasitological techniques. The survey yielded 17 parasite species: 11 from Oreochromis niloticus and ten from Clarias gariepinus. Four parasites-Amirthalingamia macracantha, Monobothrioides sp., Zoogonoides sp. and a member of the family Amphilinidae-were recorded for the first time in the country. The parasite diversity was similar between hosts; however, O. niloticus was dominated by free-living stage-transmitted parasites in lower numbers, whereas both trophically and free-living stage-transmitted parasites were equally represented in C. gariepinus in relatively high intensities. The patterns in parasite numbers and composition in the two hosts reflect differences in fish habitat use and diet. A shift in parasite composition from monoxenous species-dominated communities in small-sized fish to heteroxenous in large fishes was recorded in both hosts. This was linked to ontogenetic feeding changes and prolonged exposure to parasites. Polyculture systems showed no effect on parasite intensity and composition. The gills were highly parasitized, mainly by protozoans and monogeneans. Generally, the occurrence and diversity of parasites in these fish species highlight the likelihood of disease outbreak in the proposed intensive aquaculture systems. This calls for raising awareness in fish health management among potential farmers, service providers and researchers.

  20. Parasite and nutrient enrichment effects on Daphnia interspecific competition.

    PubMed

    Decaestecker, Ellen; Verreydt, Dino; De Meester, Luc; Declerck, Steven A J

    2015-05-01

    Increased productivity due to nutrient enrichment is hypothesized to affect density-dependent processes, such as transmission success of horizontally transmitting parasites. Changes in nutrient availability can also modify the stoichiometry and condition of individual hosts, which may affect their susceptibility for parasites as well as the growth conditions for parasites within the host. Consequently, if not balanced by increased host immuno-competence or life history responses, changes in the magnitude of parasite effects with increasing nutrient availability are expected. If these parasite effects are host-species specific, this may lead to shifts in the host community structure. We here used the Daphnia- parasite model system to study the effect of nutrient enrichment on parasite-mediated competition in experimental mesocosms. In the absence of parasites, D. magna was competitively dominant to D. pulex at both low and high nutrient levels. Introduction of parasites resulted in infections of D. magna, but not of D. pulex and, as such, reversed the competitive hierarchy between these two species. Nutrient addition resulted in an increased prevalence and infection intensity of some of the parasites on D. magna. However, there was no evidence that high nutrient levels enhanced negative effects of parasites on the hosts. Costs associated with parasite infections may have been compensated by better growth conditions for D. magna in the presence of high nutrient levels.

  1. Encystation in parasitic protozoa.

    PubMed

    Eichinger, D

    2001-08-01

    Giardia and Entamoeba parasites encase themselves in a carbohydrate-rich cyst for travel from host to host. Both parasites upregulate their Golgi apparatus during this process, yielding organelles that are now found to be similar to those of higher eukaryotes. In fact, unusual enzymes and structural proteins used for cyst wall synthesis, the complexity of the secretory pathways used to transport materials to the developing cyst walls, as well as unexpected mechanisms of gene regulation and parasite-host and parasite-parasite information exchange, are revealing a high level of sophistication in these organisms that occupy low branch points in the eukaryotic lineage.

  2. Encystation of entamoeba parasites.

    PubMed

    Eichinger, D

    1997-07-01

    Entamoeba histolytica is a protozoan parasite of humans, and the causitive agent of intestinal amebiasis. The disease-causing stage of the parasite is an osmotically sensitive ameboid form, which differentiates into a thick-walled cyst for transmission from person to person. The conditions within the human intestine that induce encystment of the amoeba are unknown, but studies using an amoebic parasite of reptiles are now yielding information about the molecules and host:parasite interactions involved in the process. An understanding of the amoeba's obligatory encystment pathway should provide an approach for interrupting the transmission of this parasite, for which there is currently no vaccine.

  3. Estimating parasite host range.

    PubMed

    Dallas, Tad; Huang, Shan; Nunn, Charles; Park, Andrew W; Drake, John M

    2017-08-30

    Estimating the number of host species that a parasite can infect (i.e. host range) provides key insights into the evolution of host specialism and is a central concept in disease ecology. Host range is rarely estimated in real systems, however, because variation in species relative abundance and the detection of rare species makes it challenging to confidently estimate host range. We applied a non-parametric richness indicator to estimate host range in simulated and empirical data, allowing us to assess the influence of sampling heterogeneity and data completeness. After validating our method on simulated data, we estimated parasite host range for a sparsely sampled global parasite occurrence database (Global Mammal Parasite Database) and a repeatedly sampled set of parasites of small mammals from New Mexico (Sevilleta Long Term Ecological Research Program). Estimation accuracy varied strongly with parasite taxonomy, number of parasite occurrence records, and the shape of host species-abundance distribution (i.e. the dominance and rareness of species in the host community). Our findings suggest that between 20% and 40% of parasite host ranges are currently unknown, highlighting a major gap in our understanding of parasite specificity, host-parasite network structure, and parasite burdens. © 2017 The Author(s).

  4. Gastrointestinal parasite infestation.

    PubMed

    Abd El Bagi, Mohamed E; Sammak, Bassam M; Mohamed, Abdulrahman E; Al Karawi, Mohamed A; Al Shahed, Mona; Al Thagafi, Mohamed A

    2004-03-01

    Twenty-five percent of the world's population could be suffering parasitic infestation. Highest prevalence is in underdeveloped agricultural and rural areas in the tropical and subtropical regions. In some areas incidence may reach 90% of the population. In contrast, some major economic projects intended to promote local development have, paradoxically, caused parasitic proliferation, e.g. bilharziasis in Egypt and Sudan and Chagas disease in Brazil. The commonest cosmopolitan gastrointestinal parasite is Entamoeba histolytica. Some intestinal parasite are endemic in temperate climates, e.g. Entrobius vermicularis. The AIDS epidemic has increased the prevalence and severity of parasitic disease, particularly Strongyloides stercolaris. Tropical parasites are seen in Western people who travel to tropical countries. Radiology has acquired a major role in diagnosis and management of gastrointestinal parasite infestations and their complications.

  5. Cultivation of parasites.

    PubMed

    Ahmed, Nishat Hussain

    2014-07-01

    Parasite cultivation techniques constitute a substantial segment of present-day study of parasites, especially of protozoa. Success in establishing in vitro and in vivo culture of parasites not only allows their physiology, behavior and metabolism to be studied dynamically, but also allows the nature of the antigenic molecules in the excretory and secretory products to be vigorously pursued and analyzed. The complex life-cycles of various parasites having different stages and host species requirements, particularly in the case of parasitic helminths, often make parasite cultivation an uphill assignment. Culturing of parasites depends on the combined expertise of all types of microbiological cultures. Different parasites require different cultivation conditions such as nutrients, temperature and even incubation conditions. Cultivation is an important method for diagnosis of many clinically important parasites, for example, Entamoeba histolytica, Trichomonas vaginalis, Leishmania spp., Strongyloides stercoralis and free-living amoebae. Many commercial systems like InPouch TV for T. vaginalis, microaerophilous stationary phase culture for Babesia bovis and Harada-Mori culture technique for larval-stage nematodes have been developed for the rapid diagnosis of the parasitic infections. Cultivation also has immense utility in the production of vaccines, testing vaccine efficacy, and antigen - production for obtaining serological reagents, detection of drug-resistance, screening of potential therapeutic agents and conducting epidemiological studies. Though in vitro cultivation techniques are used more often compared with in vivo techniques, the in vivo techniques are sometimes used for diagnosing some parasitic infections such as trypanosomiasis and toxoplasmosis. Parasite cultivation continues to be a challenging diagnostic option. This review provides an overview of intricacies of parasitic culture and update on popular methods used for cultivating parasites.

  6. Paradigms for parasite conservation.

    PubMed

    Dougherty, Eric R; Carlson, Colin J; Bueno, Veronica M; Burgio, Kevin R; Cizauskas, Carrie A; Clements, Christopher F; Seidel, Dana P; Harris, Nyeema C

    2016-08-01

    Parasitic species, which depend directly on host species for their survival, represent a major regulatory force in ecosystems and a significant component of Earth's biodiversity. Yet the negative impacts of parasites observed at the host level have motivated a conservation paradigm of eradication, moving us farther from attainment of taxonomically unbiased conservation goals. Despite a growing body of literature highlighting the importance of parasite-inclusive conservation, most parasite species remain understudied, underfunded, and underappreciated. We argue the protection of parasitic biodiversity requires a paradigm shift in the perception and valuation of their role as consumer species, similar to that of apex predators in the mid-20th century. Beyond recognizing parasites as vital trophic regulators, existing tools available to conservation practitioners should explicitly account for the unique threats facing dependent species. We built upon concepts from epidemiology and economics (e.g., host-density threshold and cost-benefit analysis) to devise novel metrics of margin of error and minimum investment for parasite conservation. We define margin of error as the risk of accidental host extinction from misestimating equilibrium population sizes and predicted oscillations, while minimum investment represents the cost associated with conserving the additional hosts required to maintain viable parasite populations. This framework will aid in the identification of readily conserved parasites that present minimal health risks. To establish parasite conservation, we propose an extension of population viability analysis for host-parasite assemblages to assess extinction risk. In the direst cases, ex situ breeding programs for parasites should be evaluated to maximize success without undermining host protection. Though parasitic species pose a considerable conservation challenge, adaptations to conservation tools will help protect parasite biodiversity in the face of

  7. Malaria parasite clearance.

    PubMed

    White, Nicholas J

    2017-02-23

    Following anti-malarial drug treatment asexual malaria parasite killing and clearance appear to be first order processes. Damaged malaria parasites in circulating erythrocytes are removed from the circulation mainly by the spleen. Splenic clearance functions increase markedly in acute malaria. Either the entire infected erythrocytes are removed because of their reduced deformability or increased antibody binding or, for the artemisinins which act on young ring stage parasites, splenic pitting of drug-damaged parasites is an important mechanism of clearance. The once-infected erythrocytes returned to the circulation have shortened survival. This contributes to post-artesunate haemolysis that may follow recovery in non-immune hyperparasitaemic patients. As the parasites mature Plasmodium vivax-infected erythrocytes become more deformable, whereas Plasmodium falciparum-infected erythrocytes become less deformable, but they escape splenic filtration by sequestering in venules and capillaries. Sequestered parasites are killed in situ by anti-malarial drugs and then disintegrate to be cleared by phagocytic leukocytes. After treatment with artemisinin derivatives some asexual parasites become temporarily dormant within their infected erythrocytes, and these may regrow after anti-malarial drug concentrations decline. Artemisinin resistance in P. falciparum reflects reduced ring stage susceptibility and manifests as slow parasite clearance. This is best assessed from the slope of the log-linear phase of parasitaemia reduction and is commonly measured as a parasite clearance half-life. Pharmacokinetic-pharmacodynamic modelling of anti-malarial drug effects on parasite clearance has proved useful in predicting therapeutic responses and in dose-optimization.

  8. Parasites: evolution's neurobiologists.

    PubMed

    Adamo, Shelley Anne

    2013-01-01

    For millions of years, parasites have altered the behaviour of their hosts. Parasites can affect host behaviour by: (1) interfering with the host's normal immune-neural communication, (2) secreting substances that directly alter neuronal activity via non-genomic mechanisms and (3) inducing genomic- and/or proteomic-based changes in the brain of the host. Changes in host behaviour are often restricted to particular behaviours, with many other behaviours remaining unaffected. Neuroscientists can produce this degree of selectivity by targeting specific brain areas. Parasites, however, do not selectively attack discrete brain areas. Parasites typically induce a variety of effects in several parts of the brain. Parasitic manipulation of host behaviour evolved within the context of the manipulation of other host physiological systems (especially the immune system) that was required for a parasite's survival. This starting point, coupled with the fortuitous nature of evolutionary innovation and evolutionary pressures to minimize the costs of parasitic manipulation, likely contributed to the complex and indirect nature of the mechanisms involved in host behavioural control. Because parasites and neuroscientists use different tactics to control behaviour, studying the methods used by parasites can provide novel insights into how nervous systems generate and regulate behaviour. Studying how parasites influence host behaviour will also help us integrate genomic, proteomic and neurophysiological perspectives on behaviour.

  9. Parasitism affects vaccine efficacy against Streptococcus iniae in Nile tilapia

    USDA-ARS?s Scientific Manuscript database

    Tilapia culture worldwide is estimated to be US$ 5 billion and is important to domestic and global food security. Parasites and bacteria co-occur in both extensive and intensive production of tilapia. The effect of parasitism on vaccine performance in fish is little studied. The objective of this ...

  10. Intracellular Parasite Invasion Strategies

    NASA Astrophysics Data System (ADS)

    Sibley, L. D.

    2004-04-01

    Intracellular parasites use various strategies to invade cells and to subvert cellular signaling pathways and, thus, to gain a foothold against host defenses. Efficient cell entry, ability to exploit intracellular niches, and persistence make these parasites treacherous pathogens. Most intracellular parasites gain entry via host-mediated processes, but apicomplexans use a system of adhesion-based motility called ``gliding'' to actively penetrate host cells. Actin polymerization-dependent motility facilitates parasite migration across cellular barriers, enables dissemination within tissues, and powers invasion of host cells. Efficient invasion has brought widespread success to this group, which includes Toxoplasma, Plasmodium, and Cryptosporidium.

  11. Sphingolipids in parasitic protozoa

    PubMed Central

    Zhang, Kai; Bangs, James D.; Beverley, Stephen M.

    2009-01-01

    The surface of most protozoan parasites relies heavily upon lipid-anchored molecules, to form protective barriers and play critical functions required for infectivity. Sphingolipids (SLs) play important roles through their abundance and involvement in membrane microdomain formation, as well as serving as the lipid anchor for many of these molecules, and in some but possibly not all species, as important signaling molecules. Interactions of parasite sphingolipid metabolism with that of the host may potentially contribute to parasite survival and/or host defense. In this chapter we summarize current knowledge of SL structure, synthesis and function in several of the major parasitic protozoan groups. PMID:20919659

  12. Parasitism, community structure and biodiversity in intertidal ecosystems.

    PubMed

    Mouritsen, K N; Poulin, R

    2002-01-01

    There is mounting evidence that parasites can influence the composition and structure of natural animal communities. In spite of this, it is difficult to assess just how important parasitism is for community structure because very few studies have been designed specifically to address the role of parasites at the community level, no doubt because it is difficult to manipulate the abundance of parasites in field experiments. Here, we bring together a large amount of published information on parasitism in intertidal communities to highlight the potential influence of parasites on the structure and biodiversity of these communities. We first review the impact of metazoan parasites on the survival, reproduction, growth and behaviour of intertidal invertebrates, from both rocky shores and soft-sediment flats. Published evidence suggests that the impact of parasites on individuals is often severe, though their effects at the population level are dependent on prevalence and intensity of infection. We then put this information together in a discussion of the impact of parasitism at the community level. We emphasize two ways in which parasites can modify the structure of intertidal communities. First, the direct impact of parasites on the abundance of key host species can decrease the importance of these hosts in competition or predator-prey interactions with other species. Second, the indirect effects of parasites on the behaviour of their hosts, e.g. burrowing ability or spatial distribution within the intertidal zone, can cause changes to various features of the habitat for other intertidal species, leading to their greater settlement success or to their local disappearance. Our synthesis allows specific predictions to be made regarding the potential impact of parasites in certain intertidal systems, and suggests that parasites must be included in future community studies and food web models of intertidal ecosystems.

  13. Pets and Parasites

    MedlinePlus

    ... in Children and TeensRead MoreBMI Calculator Cat and Dog BitesApril 2017September 2000Pets and Animalsfamilydoctor.org editorial staffCat- ... and Parasites Share Print Pets and Parasites A dog may be man’s best friend. However, household pets ...

  14. PARASITES OF FISH

    EPA Science Inventory

    The intent of this chapter is to describe the parasites of importance to fishes maintained and used in laboratory settings. In contrast to the frist edition, the focus will be only on those parasites that pose a serious threat to or are common in fishes held in these confined en...

  15. PARASITES OF FISH

    EPA Science Inventory

    The intent of this chapter is to describe the parasites of importance to fishes maintained and used in laboratory settings. In contrast to the frist edition, the focus will be only on those parasites that pose a serious threat to or are common in fishes held in these confined en...

  16. Parasites and marine invasions

    USGS Publications Warehouse

    Torchin, M.E.; Lafferty, K.D.; Kuris, A.M.

    2002-01-01

    Introduced marine species are a major environmental and economic problem. The rate of these biological invasions has substantially increased in recent years due to the globalization of the world's economies. The damage caused by invasive species is often a result of the higher densities and larger sizes they attain compared to where they are native. A prominent hypothesis explaining the success of introduced species is that they are relatively free of the effects of natural enemies. Most notably, they may encounter fewer parasites in their introduced range compared to their native range. Parasites are ubiquitous and pervasive in marine systems, yet their role in marine invasions is relatively unexplored. Although data on parasites of marine organisms exist, the extent to which parasites can mediate marine invasions, or the extent to which invasive parasites and pathogens are responsible for infecting or potentially decimating native marine species have not been examined. In this review, we present a theoretical framework to model invasion success and examine the evidence for a relationship between parasite presence and the success of introduced marine species. For this, we compare the prevalence and species richness of parasites in several introduced populations of marine species with populations where they are native. We also discuss the potential impacts of introduced marine parasites on native ecosystems.

  17. Parasitized female guppies do not prefer showy males.

    PubMed

    López

    1999-05-01

    In many species male sexual characteristics are known to be affected negatively by parasites, which render their hosts unattractive to females, but how parasites affect the mating decisions of their female hosts has received little attention. The monogenean parasite Gyrodactylus turnbulli reduces the sexual display and colour intensity of male guppies, Poecilia reticulata, which makes them less attractive to females. Here, I examine how these parasites affect the mate choice behaviour of their female hosts. Virgin females were experimentally exposed to G. turnbulli and allowed to choose between an attractive and an unattractive male in a simultaneous choice test. Infected females were significantly less discriminatory than healthy ones and their level of activity during choice trials was reduced with increasing parasite load, suggesting an energetic constraint imposed by the parasites. This result implies that sexual selection pressure for male showiness is diminished, which is consistent with recent theoretical models. Copyright 1999 The Association for the Study of Animal Behaviour.

  18. Host-parasite relationships as determinants of heavy metal concentrations in perch (Perca fluviatilis) and its intestinal parasite infection.

    PubMed

    Brázová, Tímea; Hanzelová, Vladimíra; Miklisová, Dana; Šalamún, Peter; Vidal-Martínez, Víctor M

    2015-12-01

    The concentrations of As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, and Zn and their bioconcentration factors (BCFs) were determined in two intestinal parasites, an acanthocephalan, Acanthocephalus lucii, a tapeworm, Proteocephalus percae, present in the same host, the European perch (Perca fluviatilis, L.), in the heavily polluted Ružín reservoir in eastern Slovakia. The bioaccumulation of heavy metals in the fish organs and parasites was studied for acanthocephalan and tapeworm monoinfections or mixed infections by the two parasites and for the size of their parasitic infrapopulations. Bioconcentration factors (c[parasite]/c[muscle tissue]) showed that the concentrations of As, Ni, Pb and Zn were higher in mixed infections than in monoinfections. Negative correlations between heavy metal concentrations in perch organs and the parasites were found. For example, higher concentrations of Ni and Zn in both parasite species corresponded with lower metal concentrations in perch and hard roe. Likewise, significant negative relationships between metal concentrations in fish organs and number of parasites were noticed with lower levels of Pb in fish harbouring higher numbers of tapeworms. Similarly, in both parasite species the concentrations of some essential elements (Cr, Mn) were lower at high infection intensities compared to low intensities. Our study revealed that the differential concentration of heavy metals in perch organs was affected by the type of infection (mono- or mixed-infection), and needs to be considered in field ecotoxicological and parasitological studies as a potentially important factor influencing the pollutant concentrations in fish.

  19. Migration highways and migration barriers created by host-parasite interactions.

    PubMed

    Zhang, Quan-Guo; Buckling, Angus

    2016-12-01

    Co-evolving parasites may play a key role in host migration and population structure. Using co-evolving bacteria and viruses, we test general hypotheses as to how co-evolving parasites affect the success of passive host migration between habitats that can support different intensities of host-parasite interactions. First, we show that parasites aid migration from areas of intense to weak co-evolutionary interactions and impede migration in the opposite direction, as a result of intraspecific apparent competition mediated via parasites. Second, when habitats show qualitative difference such that some environments support parasite persistence while others do not, different population regulation forces (either parasitism or competitive exclusion) will reduce the success of migration in both directions. Our study shows that co-evolution with parasites can predictably homogenises or isolates host populations, depending on heterogeneity of abiotic conditions, with the second scenario constituting a novel type of 'isolation by adaptation'. © 2016 John Wiley & Sons Ltd/CNRS.

  20. Evaluating parasite densities and estimation of parameters in transmission systems.

    PubMed

    Heinzmann, D; Torgerson, P R

    2008-09-01

    Mathematical modelling of parasite transmission systems can provide useful information about host parasite interactions and biology and parasite population dynamics. In addition good predictive models may assist in designing control programmes to reduce the burden of human and animal disease. Model building is only the first part of the process. These models then need to be confronted with data to obtain parameter estimates and the accuracy of these estimates has to be evaluated. Estimation of parasite densities is central to this. Parasite density estimates can include the proportion of hosts infected with parasites (prevalence) or estimates of the parasite biomass within the host population (abundance or intensity estimates). Parasite density estimation is often complicated by highly aggregated distributions of parasites within the hosts. This causes additional challenges when calculating transmission parameters. Using Echinococcus spp. as a model organism, this manuscript gives a brief overview of the types of descriptors of parasite densities, how to estimate them and on the use of these estimates in a transmission model.

  1. Soil transmitted parasites in Qualyobia Governorate.

    PubMed

    El Fakahany, Amany F; Younis, Mohamed S; Ali, Ali El-Said; El-Ghareeb, Azza S; Omar, Rabab El Sayed

    2013-08-01

    The study determined the relation between prevalence of intestinal parasites and soil-transmitted parasites among households in Shiblanga representing a rural area of Qualyobia Governorate and Benha City representing an urban area of the same Governorate. The effect of soil's type on the intensity of parasites and to provide guidance on the prevention and control of soil transmitted parasitic infections for future studies in this field. This study was conducted at Benha City and Shiblanga village representing the urban and rural areas of Qualyobia Governorate. Geoparasites were investigated in-doors, around houses, in the fields and the streets from both areas. One hundred soil samples from Benha city and one hundred soil samples from Shiblanga village were collected .each hundred soil samples was collected in the form of: 25 samples from the fields, 25 samples in-indoor yards, 25 samples the streets, 25 samples around houses. Approximately 200 g soil was collected in plastic bags at 2-10 cm depth from different parts. Stool samples from households in same areas were collected after taken oral consent. All soil samples were screened for parasites using different parasitological methods (Zinc sulphate flotation, ether sédimentation technique, modified Baerman's apparatus and modified Berlese technique). All stool samples were examined using direct smear, formalinether concentration techniques for detection of helminthes eggs, and modified acid-fast staining for detection of protozoa. The results showed that 86/200 soil samples were contaminated with different parasites, the prevalence rate of 43%. Soil samples from Shiblanga village showed higher level of parasitic contamination (56%) and Benha city showed a lower level of contamination by different parasites (30%). Soil samples obtained from Manshiet El-Nour district, Benha revealed the highest level of parasitic contamination. While, in Shiblanga, El-Mansheya district revealed the highest level of parasitic

  2. Reduction of parasitic lasing

    NASA Technical Reports Server (NTRS)

    Storm, Mark E. (Inventor)

    1994-01-01

    A technique was developed which carefully retro-reflects precisely controlled amounts of light back into a laser system thereby intentionally forcing the laser system components to oscillate in a new resonator called the parasitic oscillator. The parasitic oscillator uses the laser system to provide the gain and an external mirror is used to provide the output coupling of the new resonator. Any change of gain or loss inside the new resonator will directly change the lasing threshold of the parasitic oscillator. This change in threshold can be experimentally measured as a change in the absolute value of reflectivity, provided by the external mirror, necessary to achieve lasing in the parasitic oscillator. Discrepancies between experimental data and a parasitic oscillator model are direct evidence of optical misalignment or component performance problems. Any changes in the optical system can instantly be measured as a change in threshold for the parasitic oscillator. This technique also enables aligning the system for maximum parasitic suppression with the system fully operational.

  3. Peroxiredoxins in Parasites

    PubMed Central

    Gretes, Michael C.; Poole, Leslie B.

    2012-01-01

    Abstract Significance: Parasite survival and virulence relies on effective defenses against reactive oxygen and nitrogen species produced by the host immune system. Peroxiredoxins (Prxs) are ubiquitous enzymes now thought to be central to such defenses and, as such, have potential value as drug targets and vaccine antigens. Recent Advances: Plasmodial and kinetoplastid Prx systems are the most extensively studied, yet remain inadequately understood. For many other parasites our knowledge is even less well developed. Through parasite genome sequencing efforts, however, the key players are being discovered and characterized. Here we describe what is known about the biochemistry, regulation, and cell biology of Prxs in parasitic protozoa, helminths, and fungi. At least one Prx is found in each parasite with a sequenced genome, and a notable theme is the common patterns of expression, localization, and functionality among sequence-similar Prxs in related species. Critical Issues: The nomenclature of Prxs from parasites is in a state of disarray, causing confusion and making comparative inferences difficult. Here we introduce a systematic Prx naming convention that is consistent between organisms and informative about structural and evolutionary relationships. Future Directions: The new nomenclature should stimulate the crossfertilization of ideas among parasitologists and with the broader redox research community. The diverse parasite developmental stages and host environments present complex systems in which to explore the variety of roles played by Prxs, with a view toward parlaying what is learned into novel therapies and vaccines that are urgently needed. Antioxid. Redox Signal. 17, 608–633. PMID:22098136

  4. [Relationship between biomass and parasite density of Mediorhynchus emberizae (Acanthocephala: Gigantorhynchidae) parasites of Paroaria dominicana (Passeriformes: Emberizidae) of the State of Bahia, Brazil].

    PubMed

    Carvalho, Adriano R; Souza-Lima, Sueli; Tavares, Luiz E R; Luque, José L

    2008-01-01

    During the study of the metazoan parasites of Paroaria dominicana (Linnaeus, 1758), eight infrapopulations of Mediorhynchus emberizae (Rudolphi, 1819), were collected in the medium third of the small intestine, with parasite intensities ranging from one to ten specimens. Differences among the average values of the biomass, volume of the eggs, volume of the testicles and the parasite density of the infrapopulations were statistically tested in order to detect variations of these parameters in function of parasite density. Was observed that the acanthocephalans biomass increased with the volume of the intestine and also that the parasite density increased with the parasite intensity in the infrapopulations. It was verified that the increase of the parasite intensity was accompanied by the decrease of the mean biomass of the parasites. Decrease of the volume of the eggs was verified with the increase of the density and of the parasite intensity. The results of the present work could suggested the occurrence of density-dependent factors and the decrease of testicles volume and the biomass of the males with the increase of the parasite density in the infrapopulations of M. emberizae in the intestine of P. dominicana.

  5. MATRIX ASSISTED LASER DESORPTION/IONIZATION TIME OF FLIGHT MASS SPECTROMETRY BASED ANALYSIS OF GIARDIA LAMBLIA

    EPA Science Inventory

    Giardia lamblia is a zoonotic protozoan parasite that is a leading cause of drinking water related gastro-intestinal disease outbreaks worldwide. Due to the genotypic complexity and high prevalence of this parasite in the environment, numerous research studies are being done to ...

  6. MATRIX ASSISTED LASER DESORPTION/IONIZATION TIME OF FLIGHT MASS SPECTROMETRY BASED ANALYSIS OF GIARDIA LAMBLIA

    EPA Science Inventory

    Giardia lamblia is a zoonotic protozoan parasite that is a leading cause of drinking water related gastro-intestinal disease outbreaks worldwide. Due to the genotypic complexity and high prevalence of this parasite in the environment, numerous research studies are being done to ...

  7. [Parasitism and ecological parasitology].

    PubMed

    Balashov, Iu S

    2011-01-01

    Parasitism as one of the life modes is a general biological phenomenon and is a characteristic of all viruses, many taxa of bacteria, fungi, protists, metaphytes, and metazoans. Zooparasitology is focused on studies of parasitic animals, particularly, on their taxonomy, anatomy, life cycles, host-parasite relations, biocoenotic connections, and evolution. Ecological parasitology is a component of ecology, as the scientific study of the relation of living organisms with each other and their surroundings. In the present paper, critical analysis of the problems, main postulates, and terminology of the modern ecological parasitology is given.

  8. Bird brood parasitism.

    PubMed

    Stevens, Martin

    2013-10-21

    For many animals, the effort to rear their young is considerable. In birds, this often includes building nests, incubating eggs, feeding the chicks, and protecting them from predators. Perhaps for this reason, about 1% of birds (around 100 species) save themselves the effort and cheat instead. They are obligate brood parasites, laying their eggs in the nests of other species and leaving the hosts or foster parents to rear the foreign chicks for them. Some birds also cheat on individuals of the same species (intraspecific brood parasitism). Intraspecific brood parasitism has been reported in around 200 species, but is likely to be higher, as it can often only be detected by genetic analyses.

  9. Mutual dilution of infection by an introduced parasite in native and invasive stream fishes across Hawaii.

    PubMed

    Gagne, Roderick B; Heins, David C; McIntyre, Peter B; Gilliam, James F; Blum, Michael J

    2016-10-01

    The presence of introduced hosts can increase or decrease infections of co-introduced parasites in native species of conservation concern. In this study, we compared parasite abundance, intensity, and prevalence between native Awaous stamineus and introduced poeciliid fishes by a co-introduced nematode parasite (Camallanus cotti) in 42 watersheds across the Hawaiian Islands. We found that parasite abundance, intensity and prevalence were greater in native than introduced hosts. Parasite abundance, intensity and prevalence within A. stamineus varied between years, which largely reflected a transient spike in infection in three remote watersheds on Molokai. At each site we measured host factors (length, density of native host, density of introduced host) and environmental factors (per cent agricultural and urban land use, water chemistry, watershed area and precipitation) hypothesized to influence C. cotti abundance, intensity and prevalence. Factors associated with parasitism differed between native and introduced hosts. Notably, parasitism of native hosts was higher in streams with lower water quality, whereas parasitism of introduced hosts was lower in streams with lower water quality. We also found that parasite burdens were lower in both native and introduced hosts when coincident. Evidence of a mutual dilution effect indicates that introduced hosts can ameliorate parasitism of native fishes by co-introduced parasites, which raises questions about the value of remediation actions, such as the removal of introduced hosts, in stemming the rise of infectious disease in species of conservation concern.

  10. Intestinal parasitism in Malayan aborigines (Orang Asli)*

    PubMed Central

    Dunn, F. L.

    1972-01-01

    Surveys were conducted in the southern Malay peninsula to assess intestinal parasitism in the aboriginal ethnic minority groups. Faecal specimens from 1 273 persons were examined by the thiomersal—iodine—formol direct-smear technique. Prevalences are reported and, for helminth infections, data on worm burdens. The state of sanitation in each of 9 cultural-ecological groups was assessed by means of a simplified system of scoring for variables. Particular attention was paid to relationships between cultural and ecological factors, sanitation, and observed patterns of intestinal parasitism. The author also discusses the fact that the number of parasitic species diminishes in habitats simplified by man, whereas an increase occurs in the prevalence and intensity of the more adaptable species that persist in ecosystems of low complexity. PMID:4537337

  11. Metabolomics and protozoan parasites.

    PubMed

    Paget, Timothy; Haroune, Nicolas; Bagchi, Sushmita; Jarroll, Edward

    2013-06-01

    In this review, we examine the state-of-the-art technologies (gas and liquid chromatography, mass spectroscopy and nuclear magnetic resonance, etc.) in the well-established area of metabolomics especially as they relate to protozoan parasites.

  12. Children and Parasitic Diseases

    MedlinePlus

    ... conditioned room, and wear protective clothing. Soil-transmitted helminth (STH) diseases ("helminth" means parasitic worm) are of major importance in ... later in life. It is caused by a helminth that spends part of its life cycle in ...

  13. Cytoskeleton of Apicomplexan Parasites

    PubMed Central

    Morrissette, Naomi S.; Sibley, L. David

    2002-01-01

    The Apicomplexa are a phylum of diverse obligate intracellular parasites including Plasmodium spp., the cause of malaria; Toxoplasma gondii and Cryptosporidium parvum, opportunistic pathogens of immunocompromised individuals; and Eimeria spp. and Theileria spp., parasites of considerable agricultural importance. These protozoan parasites share distinctive morphological features, cytoskeletal organization, and modes of replication, motility, and invasion. This review summarizes our current understanding of the cytoskeletal elements, the properties of cytoskeletal proteins, and the role of the cytoskeleton in polarity, motility, invasion, and replication. We discuss the unusual properties of actin and myosin in the Apicomplexa, the highly stereotyped microtubule populations in apicomplexans, and a network of recently discovered novel intermediate filament-like elements in these parasites. PMID:11875126

  14. Parasites and human evolution.

    PubMed

    Perry, George H

    2014-01-01

    Our understanding of human evolutionary and population history can be advanced by ecological and evolutionary studies of our parasites. Many parasites flourish only in the presence of very specific human behaviors and in specific habitats, are wholly dependent on us, and have evolved with us for thousands or millions of years. Therefore, by asking when and how we first acquired those parasites, under which environmental and cultural conditions we are the most susceptible, and how the parasites have evolved and adapted to us and we in response to them, we can gain considerable insight into our own evolutionary history. As examples, the tapeworm life cycle is dependent on our consumption of meat, the divergence of body and head lice may have been subsequent to the development of clothing, and malaria hyperendemicity may be associated with agriculture. Thus, the evolutionary and population histories of these parasites are likely intertwined with critical aspects of human biology and culture. Here I review the mechanics of these and multiple other parasite proxies for human evolutionary history and discuss how they currently complement our fossil, archeological, molecular, linguistic, historical, and ethnographic records. I also highlight potential future applications of this promising model for the field of evolutionary anthropology.

  15. Parasite Carbohydrate Vaccines

    PubMed Central

    Jaurigue, Jonnel A.; Seeberger, Peter H.

    2017-01-01

    Vaccination is an efficient means of combating infectious disease burden globally. However, routine vaccines for the world's major human parasitic diseases do not yet exist. Vaccines based on carbohydrate antigens are a viable option for parasite vaccine development, given the proven success of carbohydrate vaccines to combat bacterial infections. We will review the key components of carbohydrate vaccines that have remained largely consistent since their inception, and the success of bacterial carbohydrate vaccines. We will then explore the latest developments for both traditional and non-traditional carbohydrate vaccine approaches for three of the world's major protozoan parasitic diseases—malaria, toxoplasmosis, and leishmaniasis. The traditional prophylactic carbohydrate vaccine strategy is being explored for malaria. However, given that parasite disease biology is complex and often arises from host immune responses to parasite antigens, carbohydrate vaccines against deleterious immune responses in host-parasite interactions are also being explored. In particular, the highly abundant glycosylphosphatidylinositol molecules specific for Plasmodium, Toxoplasma, and Leishmania spp. are considered exploitable antigens for this non-traditional vaccine approach. Discussion will revolve around the application of these protozoan carbohydrate antigens for vaccines currently in preclinical development. PMID:28660174

  16. Synergistic effects of seasonal rainfall, parasites and demography on fluctuations in springbok body condition

    PubMed Central

    Turner, Wendy C.; Versfeld, Wilferd D.; Kilian, J. Werner; Getz, Wayne M.

    2011-01-01

    Summary 1. Seasonality of rainfall can exert a strong influence on animal condition and on host-parasite interactions. The body condition of ruminants fluctuates seasonally in response to changes in energy requirements, foraging patterns and resource availability, and seasonal variation in parasite infections may further alter ruminant body condition. 2. This study disentangles effects of rainfall and gastrointestinal parasite infections on springbok (Antidorcas marsupialis) body condition and determines how these factors vary among demographic groups. 3. Using data from four years and three study areas, we investigated i) the influence of rainfall variation, demographic factors and parasite interactions on parasite prevalence or infection intensity, ii) whether parasitism or rainfall is a more important predictor of springbok body condition and iii) how parasitism and condition vary among study areas along a rainfall gradient. 4. We found that increased parasite intensity is associated with reduced body condition only for adult females. For all other demographic groups, body condition was significantly related to prior rainfall and not to parasitism. Rainfall lagged by two months had a positive effect on body condition. 5. Adult females showed evidence of a “periparturient rise” in parasite intensity, and had higher parasite intensity and lower body condition than adult males after parturition and during early lactation. After juveniles were weaned, adult females had lower parasite intensity than adult males. Sex differences in parasitism and condition may be due to differences between adult females and males in the seasonal timing of reproductive effort and its effects on host immunity, as well as documented sex differences in vulnerability to predation. 6. Our results highlight that parasites and the environment can synergistically affect host populations, but that these interactions might be masked by their interwoven relationships, their differential

  17. Synergistic effects of seasonal rainfall, parasites and demography on fluctuations in springbok body condition.

    PubMed

    Turner, Wendy C; Versfeld, Wilferd D; Kilian, J Werner; Getz, Wayne M

    2012-01-01

    1. Seasonality of rainfall can exert a strong influence on animal condition and on host-parasite interactions. The body condition of ruminants fluctuates seasonally in response to changes in energy requirements, foraging patterns and resource availability, and seasonal variation in parasite infections may further alter ruminant body condition. 2. This study disentangles the effects of rainfall and gastrointestinal parasite infections on springbok (Antidorcas marsupialis) body condition and determines how these factors vary among demographic groups. 3. Using data from four years and three study areas, we investigated (i) the influence of rainfall variation, demographic factors and parasite interactions on parasite prevalence or infection intensity, (ii) whether parasitism or rainfall is a more important predictor of springbok body condition and (iii) how parasitism and condition vary among study areas along a rainfall gradient. 4. We found that increased parasite intensity is associated with reduced body condition only for adult females. For all other demographic groups, body condition was significantly related to prior rainfall and not to parasitism. Rainfall lagged by two months had a positive effect on body condition. 5. Adult females showed evidence of a 'periparturient rise' in parasite intensity and had higher parasite intensity and lower body condition than adult males after parturition and during early lactation. After juveniles were weaned, adult females had lower parasite intensity than adult males. Sex differences in parasitism and condition may be due to differences between adult females and males in the seasonal timing of reproductive effort and its effects on host immunity, as well as documented sex differences in vulnerability to predation. 6. Our results highlight that parasites and the environment can synergistically affect host populations, but that these interactions might be masked by their interwoven relationships, their differential impacts on

  18. Host social behavior and parasitic infection: A multifactorial approach

    USGS Publications Warehouse

    Ezenwa, V.O.

    2004-01-01

    I examined associations between several components of host social organization, including group size and gregariousness, group stability, territoriality and social class, and gastrointestinal parasite load in African bovids. At an intraspecific level, group size was positively correlated with parasite prevalence, but only when the parasite was relatively host specific and only among host species living in stable groups. Social class was also an important predictor of infection rates. Among gazelles, territorial males had higher parasite intensities than did either bachelor males or females and juveniles, suggesting that highly territorial individuals may be either more exposed or more susceptible to parasites. Associations among territoriality, grouping, and parasitism were also found across taxa. Territorial host genera were more likely to be infected with strongyle nematodes than were nonterritorial hosts, and gregarious hosts were more infected than were solitary hosts. Analyses also revealed that gregariousness and territoriality had an interactive effect on individual parasite richness, whereby hosts with both traits harbored significantly more parasite groups than did hosts with only one or neither trait. Overall, study results indicate that multiple features of host social behavior influence infection risk and suggest that synergism between traits also has important effects on host parasite load.

  19. Parasites in marine food webs

    USGS Publications Warehouse

    Lafferty, Kevin D.

    2013-01-01

    Most species interactions probably involve parasites. This review considers the extent to which marine ecologists should consider parasites to fully understand marine communities. Parasites are influential parts of food webs in estuaries, temperate reefs, and coral reefs, but their ecological importance is seldom recognized. Though difficult to observe, parasites can have substantial biomass, and they can be just as common as free-living consumers after controlling for body mass and trophic level. Parasites have direct impacts on the energetics of their hosts and some affect host behaviors, with ecosystem-level consequences. Although they cause disease, parasites are sensitive components of ecosystems. In particular, they suffer secondary extinctions due to biodiversity loss. Some parasites can also return to a system after habitat restoration. For these reasons, parasites can make good indicators of ecosystem integrity. Fishing can indirectly increase or decrease parasite populations and the effects of climate change on parasites are likely to be equally as complex.

  20. Population abundance and sex ratio in dioecious helminth parasites.

    PubMed

    Poulin, Robert

    1997-07-01

    Parasite populations are highly fragmented in space and time, and consist of aggregates of genetically similar individuals sharing the same host. To avoid inbreeding, theory predicts that female-biased sex ratios should be strongly favoured when either or both prevalence and intensity of infection are low. Other models indicate that if sex ratios are selected to increase the probability of mating, they should be less biased at a high intensity of infection in polygamous parasites, since at high intensities all females are mated. To test these predictions, the relationship between sex ratio and both the prevalence and intensity of infection was examined in comparative studies across 193 populations of nematode and acanthocephalan parasites. Sex ratios in these two dioecious, polygamous taxa are usually female biased. Among natural populations, no significant relationship was observed once the confounding effects of phylogeny had been removed. However, among experimental populations of nematodes, a negative relationship was found between intensity of infection and sex ratio, even after controlling for phylogeny. In other words, at high intensities, populations of nematodes are less female biased. This result must be treated with caution because of the unusually high numbers of worms per host in experimental infections. Nevertheless, combined with information on the proximate mechanisms regulating sex ratios in these parasites, it suggests a link between the characteristics of parasite populations and their sex ratio.

  1. Gastro-intestinal microbiota of two migratory shorebird species during spring migration staging in Delaware Bay, USA

    EPA Science Inventory

    Migratory birds travel long distances and use diverse habitats, potentially exposing them to a broad range of microbes that could negatively affect their health and survival. Gut microbiota composition has been shown to be closely related to organismal health through interactions...

  2. Impact of the Fenton process in meat digestion as assessed using an in vitro gastro-intestinal model.

    PubMed

    Oueslati, Khaled; de La Pomélie, Diane; Santé-Lhoutellier, Véronique; Gatellier, Philippe

    2016-10-15

    The production of oxygen free radicals catalysed by non-haem iron was investigated in an in vitro mimetic model of the digestive tract using specific chemical traps. Superoxide radicals (O2(∗-)) and their protonated form (hydroperoxyl radicals, HO2(∗)) were detected by the reduction of nitroblue tetrazolium into formazan, and hydroxyl radicals (OH(∗)) were detected by the hydroxylation of terephthalate. Under gastric conditions, O2(∗-)/HO2(∗) were detected in higher quantity than OH(∗). Increasing the pH from 3.5 to 6.5 poorly affected the kinetics of free radical production. The oxidations generated by these free radicals were estimated on myofibrils prepared from pork rectus femoris muscle. Myofibrillar lipid and protein oxidation increased with time and oxidant concentration, with a negative impact on the digestibility of myofibrillar proteins. Plant food antioxidants considerably decreased free radical production and lipid oxidation but not protein oxidation.

  3. Degradation of phytate in the gut of pigs--pathway of gastro-intestinal inositol phosphate hydrolysis and enzymes involved.

    PubMed

    Schlemmer, U; Jany, K D; Berk, A; Schulz, E; Rechkemmer, G

    2001-01-01

    The present study gives an overview on the whole mechanism of phytate degradation in the gut and the enzymes involved. Based on the similarity of the human and pigs gut, the study was carried out in pigs as model for humans. To differentiate between intrinsic feed phytases and endogenous phytases hydrolysing phytate in the gut, two diets, one high (control diet) and the other one very low in intrinsic feed phytases (phytase inactivated diet) were applied. In the chyme of stomach, small intestine and colon inositol phosphate isomers and activities of phytases and alkaline phosphatases were determined. In parallel total tract phytate degradation and apparent phosphorus digestibility were assessed. In the stomach chyme of pigs fed the control diet, comparable high phytase activity and strong phytate degradation were observed. The predominant phytate hydrolysis products were inositol phosphates, typically formed by plant phytases. For the phytase inactivated diet, comparable very low phytase activity and almost no phytate degradation in the stomach were determined. In the small intestine and colon, high activity of alkaline phosphatases and low activity of phytases were observed, irrespective of the diet fed. In the colon, stronger phytate degradation for the phytase inactivated diet than for the control diet was detected. Phytate degradation throughout the whole gut was nearly complete and very similar for both diets while the apparent availability of total phosphorus was significantly higher for the pigs fed the control diet than the phytase inactivated diet. The pathway of inositol phosphate hydrolysis in the gut has been elucidated.

  4. Immunoreactivity for Thymosin Beta 4 and Thymosin Beta 10 in the Adult Rat Oro-Gastro-Intestinal tract

    PubMed Central

    Nemolato, S; Ekstrom, J.; Cabras, T.; Gerosa, C.; Fanni, D.; Di Felice, E.; Locci, A.; Messana, I.; Castagnola, M.; Faa, G.

    2013-01-01

    Thymosin beta 4 (Tβ4) and thymosin beta 10 (Tβ10) are two members of the β-thymosin family, involved in multiple cellular activities in different organs in multiple animal species. Here we report the expression pattern of Tβ4 and Tβ10 in rat tissues, in the gut and in annexed glands. The two peptide were differently expressed: Tβ4 was absent in salivary glands whereas Tβ10 was expressed in parotid and in submandibular glands. Tβ4 was mildly expressed in the tongue and in the esophagus, where Tβ10 was absent. A similar expression was found in the stomach, ileum and colon mucosa. In pancreas Tβ4 reactivity was restricted to the Langerhans islet cells; Tβ4 was also detected in the exocrine cells. Both peptide were not expressed in liver cells. When the rat expression pattern in rat organs was compared to reactivity for Tβ4 and Tβ10 in humans, marked differences were found. Our data clearly indicate a species-specific expression of Tβ4 and Tβ10, characterized by the actual unpredictability of the expression of these peptides in different cells and tissues. The common high expression of Tβ4 in mast cells, both in humans and in rats, represents one of the few similarities between these two species. PMID:23807296

  5. Gastro-intestinal microbiota of two migratory shorebird species during spring migration staging in Delaware Bay, USA

    EPA Science Inventory

    Migratory birds travel long distances and use diverse habitats, potentially exposing them to a broad range of microbes that could negatively affect their health and survival. Gut microbiota composition has been shown to be closely related to organismal health through interactions...

  6. Gelatin hydrolysates from farmed Giant catfish skin using alkaline proteases and its antioxidative function of simulated gastro-intestinal digestion.

    PubMed

    Ketnawa, Sunantha; Martínez-Alvarez, Oscar; Benjakul, Soottawat; Rawdkuen, Saroat

    2016-02-01

    This work aims to evaluate the ability of different alkaline proteases to prepare active gelatin hydrolysates. Fish skin gelatin was hydrolysed by visceral alkaline-proteases from Giant catfish, commercial trypsin, and Izyme AL®. All antioxidant activity indices of the hydrolysates increased with increasing degree of hydrolysis (P<0.05). The hydrolysates obtained with Izyme AL® and visceral alkaline-proteases showed the highest and lowest radical scavenging capacity, while prepared with commercial trypsin was the most effective in reducing ferric ions and showed the best metal chelating properties. The hydrolysate obtained with Izyme AL® showed the lowest iron reducing ability, but provided the highest average molecular weight (⩾ 7 kDa), followed by commercial trypsin (2.2 kDa) and visceral alkaline-proteases (1.75 kDa). After in vitro gastrointestinal digestion, the hydrolysates showed significant higher radical scavenging, reducing ferric ions and chelating activities. Gelatin hydrolysates, from fish skin, could serve as a potential source of functional food ingredients for health promotion.

  7. [The experimental study on melatonin gastro intestinal motility and plasma levels of stress hormones in overtraining rat].

    PubMed

    Jing, Hui-feng; Wang, Xiao-mei

    2015-09-01

    To study the effect of melatonin on the gastrointestinal motility and plasma levels of the stress hormone in overtraining rats. Thirty adult SD rats were randomly divided into three groups (n = 10): control group, over-training group, melatonin intervention group. 30 min before each training, rats in the control and over-training groups were fed with normal saline (15 mg/kg) once a day and 5 times per week, while rats in the melatonin intervention group were administrated with melatonin, perfusion in the intervention group (15 mg/kg). Excessive training group and melatonin intervention group rats were subjected to excessive training at 5 times a week for 6 weeks. After 6 weeks, the gastric emptying rate, small intestinal propulsion ratio and levels of plasma motilin (MTL) and calcitonin gene-related peptide (CGRP), cortisol (CORT) and catecholamines (CA) were observed in all groups. Compared with the control group, the gastric emptying rate, small intestinal propulsion ratio and levels of plasma MTL, CORT and CA were increased significantly (P < 0.01) while the content of CGRP was reduced (P < 0.01) in over-training group. After treated with melatonin, this trend was reversed, that was, the gastric emptying rate, small intestinal propulsion ratio and levels of plasma MTL, CORT and CA were surpressed significantly (P < 0.01) while the content of CGRP was improved obviously (P < 0.01) in over-training group. Melatonin plays an important role in protecting gastrointestinal tract from dysfunction, in which MTL, CGRP, CORT and CA are all involved.

  8. Little consensus in either definition or diagnosis of a lower gastro-intestinal anastomotic leak amongst colorectal surgeons.

    PubMed

    Adams, K; Papagrigoriadis, S

    2013-07-01

    The purposes of this study were to assess the working definition of a colorectal anastomotic leak among colorectal surgeons and to survey the current approach to investigation and management of a patient with a suspected anastomotic leak. Online survey consisting of nine questions regarding the definition, assessment and investigation of anastomotic leaks was conducted. Of the 738 eligible ACP members contacted, 210 responded (28.4%). Results demonstrated that 94.2% of surgeons agreed 'extravasation of contrast on enema' and 91.8% agreed 'faecal material seen in drains/from the wound' constituted a clinical leak. Only 69.2% agreed that a leak was 'intra-abdominal sepsis requiring a laparotomy', and about half agreed that radiological collections constituted a leak when either treated with antibiotics (46.6%) or with percutaneous drainage (51.4%). Serial clinical examination was the perceived most sensitive clinical feature for a leak, with 75% of surgeons ranking this in their top three choices. Surgeons radiologically confirm a leak on average in 80.2% of cases. A CT with rectal contrast for a left-sided leak was selected by 42.9% of respondents. For a right-sided/small bowel anastomosis, 44.5% selected a CT with oral contrast and 43.4% a CT with IV contrast. There is still significant heterogeneity between surgeons in what they define as an anastomotic leak. Most surgeons valued clinical examination as the most sensitive initial tool for leak detection; however, radiology has a major role in the confirmation of clinical leaks in colorectal patients. There is an increasing need to be able to classify and grade anastomotic leaks, both to improve the care of patients and for audit purposes.

  9. Gastro-intestinal delivery of influenza subunit vaccine formulation adjuvanted with Gram-positive enhancer matrix (GEM) particles.

    PubMed

    Saluja, V; Visser, M R; van Roosmalen, M L; Leenhouts, K; Huckriede, A; Hinrichs, W L J; Frijlink, H W

    2010-11-01

    In this study, a liquid formulation of influenza subunit vaccine admixed with Gram-positive enhancer matrix (GEM) particles as adjuvant was delivered to upper and lower parts of intestinal tract. The aim was to determine the most effective immunization site in the intestines. Mice were vaccinated with a liquid formulation of GEM and influenza subunit vaccine orally and rectally. The oral administration of the vaccine with GEM particles induced a better systemic and mucosal immune response than oral (vaccine only) and rectal (with and without adjuvant) immunizations. Rectal administration elicited high IgG1 responses but little IgG2a, indicating a Th2 dominated immune response. In contrast, the oral immunization with GEM particles elicited a balanced IgG1 and IgG2a response. In conclusion, our results demonstrate that GEM-adjuvanted influenza vaccine should be targeted to the upper part of the intestinal tract. Copyright © 2010 Elsevier B.V. All rights reserved.

  10. [Adrenergic reactivity of the gastro-intestinal tract. II. Colon of the guinea pig and cecum of the mice].

    PubMed

    Grana, E; Zonta, F; Lucchelli, A

    1976-05-01

    A study has been made of the alpha- and beta-adrenoreceptors in the guinea pig colon and the mouse caecum using noradrenalina as agonist and alpha- and beta-adrenolytics separately or together. In the guinea pig colon alpha-adrenolytics used alone did not alter the action of noradrenalin: one beta-lytic (propranolol) used alone has slight non dose-dependent action. The alpha-lytics used together with beta-lytic strongly potential their effect. These results are interpreted as indicating that the preparation contains alpha-receptors as well as beta-receptors; activation of the alpha-receptors is observed only when the beta-mimetic effect of noradrenalin is inhibited. In the mouse caecum alpha-lytics prove devoid of effect either alone or when associated with beta-lytics; it is deduced therefore that this preparation contains only beta-receptors.

  11. Characterisation of CART-containing neurons and cells in the porcine pancreas, gastro-intestinal tract, adrenal and thyroid glands

    PubMed Central

    Wierup, Nils; Gunnarsdóttir, Anna; Ekblad, Eva; Sundler, Frank

    2007-01-01

    Background The peptide CART is widely expressed in central and peripheral neurons, as well as in endocrine cells. Known peripheral sites of expression include the gastrointestinal (GI) tract, the pancreas, and the adrenal glands. In rodent pancreas CART is expressed both in islet endocrine cells and in nerve fibers, some of which innervate the islets. Recent data show that CART is a regulator of islet hormone secretion, and that CART null mutant mice have islet dysfunction. CART also effects GI motility, mainly via central routes. In addition, CART participates in the regulation of the hypothalamus-pituitary-adrenal-axis. We investigated CART expression in porcine pancreas, GI-tract, adrenal glands, and thyroid gland using immunocytochemistry. Results CART immunoreactive (IR) nerve cell bodies and fibers were numerous in pancreatic and enteric ganglia. The majority of these were also VIP IR. The finding of intrinsic CART containing neurons indicates that pancreatic and GI CART IR nerve fibers have an intrinsic origin. No CART IR endocrine cells were detected in the pancreas or in the GI tract. The adrenal medulla harboured numerous CART IR endocrine cells, most of which were adrenaline producing. In addition CART IR fibers were frequently seen in the adrenal cortex and capsule. The capsule also contained CART IR nerve cell bodies. The majority of the adrenal CART IR neuronal elements were also VIP IR. CART IR was also seen in a substantial proportion of the C-cells in the thyroid gland. The majority of these cells were also somatostatin IR, and/or 5-HT IR, and/or VIP IR. Conclusion CART is a major neuropeptide in intrinsic neurons of the porcine GI-tract and pancreas, a major constituent of adrenaline producing adrenomedullary cells, and a novel peptide of the thyroid C-cells. CART is suggested to be a regulatory peptide in the porcine pancreas, GI-tract, adrenal gland and thyroid. PMID:17625001

  12. Persistent Pediatric Gastro-Intestinal Myiasis: A Case Report of Fly Larval Infestation with Musca Domestica with Review of Literature

    PubMed Central

    Kandi, Venkataramana; Lal, Sandeep Kumar; Akhila; Shruthi; Sandhya, K.; Simar, Harender; Pranuthi, Mispah; Kumar, Moses Vinay; Anand, Kalaskar; Rao, Sanjeev D.

    2013-01-01

    The occurrence of dipterous fly larvae in human is termed as human myiasis. Human myiasis can be classified based on clinical condition it causes like cutaneous myiasis, ocular myiasis, urogenital myiasis and intestinal myiasis. Based on the need for a particular host, myiasis can be divided as specific myiasis, semi-specific myiasis. Accidental myiasis results when the fly larvae are deposited/ingested by human resulting in infestation, which is also called as pseudomyiasis. Fly larvae may be present on the dead and decaying organic matter and domestic animals like dog and cats which are naturally infested with fly larvae and can be source for infection in children. Very few cases have been retrieved from literature on the occurrence of intestinal myiasis in children throughout the world. We report a case of two siblings in the same family infested with dipterous fly larvae. PMID:24049366

  13. Evaluation of the NOW Malaria Immunochromatographic Test for Quantitative Diagnosis of Falciparum and Vivax Malaria Parasite Density

    PubMed Central

    Katakai, Yuko; Komaki-Yasuda, Kanako; Tangpukdee, Noppadon; Wilairatana, Polrat; Krudsood, Srivicha; Kano, Shigeyuki

    2011-01-01

    The NOW® Malaria Test, an immunochromatographic test (ICT), was evaluated to determine its ability to quantitatively detect malaria parasites using 100 blood samples from Thailand, including 50 Plasmodium falciparum (Pf) infections and 50 P. vivax (Pv) infections. Intensities of the thickness of the visible bands of the positive ICT were compared with the parasite densities. In cases of Pf infection, the intensities of both HRP-2 bands (T1 bands: Pf specific bands) and aldolase bands (T2 bands: pan-Plasmodium bands) correlated with the parasite densities. The intensities of T2 bands in Pf positive samples showed better correlation with the parasite densities than the T1 bands. In the cases of Pv infection, the intensities of T2 bands were also well correlated with parasite density. These results suggest that the ICT is useful not only for rapid detection of malaria parasites but also for estimating parasite density. PMID:22438699

  14. Evaluation of the NOW Malaria Immunochromatographic Test for Quantitative Diagnosis of Falciparum and Vivax Malaria Parasite Density.

    PubMed

    Katakai, Yuko; Komaki-Yasuda, Kanako; Tangpukdee, Noppadon; Wilairatana, Polrat; Krudsood, Srivicha; Kano, Shigeyuki

    2011-12-01

    The NOW® Malaria Test, an immunochromatographic test (ICT), was evaluated to determine its ability to quantitatively detect malaria parasites using 100 blood samples from Thailand, including 50 Plasmodium falciparum (Pf) infections and 50 P. vivax (Pv) infections. Intensities of the thickness of the visible bands of the positive ICT were compared with the parasite densities. In cases of Pf infection, the intensities of both HRP-2 bands (T1 bands: Pf specific bands) and aldolase bands (T2 bands: pan-Plasmodium bands) correlated with the parasite densities. The intensities of T2 bands in Pf positive samples showed better correlation with the parasite densities than the T1 bands. In the cases of Pv infection, the intensities of T2 bands were also well correlated with parasite density. These results suggest that the ICT is useful not only for rapid detection of malaria parasites but also for estimating parasite density.

  15. Parasitism, immune response and reproductive success in the house martin Delichonurbica.

    PubMed

    de Lope, F; Møller, A P; de la Cruz, C

    1998-04-01

    Parasites often exert strong selection pressures on their hosts that have evolved anti-parasite defences to counter the negative effects of parasites. We studied the relationship between intensity of parasitism, one aspect of host immune response, and host reproductive success, using the house martin bug Oeciacushirundinis and its house martin Delichonurbica host as a model system. Experimental manipulation of parasite load of nests during laying of the first clutch altered the intensity of parasitism. Parasites reduced the reproductive success of their hosts measured in terms of body condition and survival of nestlings. Host immune response, measured as the concentration of gammaglobulins and total plasma proteins, was positively associated with parasite reproduction, estimated as the number of juvenile parasites, but was only weakly related to the intensity of adult parasites. The concentration of gammaglobulins was negatively related to nestling body mass, implying a trade-off between immune function and body condition. Parasite reproduction thus exerts a cost on hosts by increasing the immune response.

  16. Plants, endosymbionts and parasites

    PubMed Central

    Nagamune, Kisaburo; Xiong, Liming; Chini, Eduardo

    2008-01-01

    It was recently discovered that the protozoan parasite, Toxoplasma gondii produces and uses the plant hormone, abscisic acid (ABA), for communication. Following intracellular replication, ABA production influences the timing of parasite egress from the host cell. This density-dependent signal may serve to coordinate exit from the host cell in a synchronous manner by triggering calcium-dependent activation of motility. In the absence of ABA production, parasites undergo differentiation to the semidormant, tissue cyst. The pathway for ABA production in T. gondii may be derived from a relict endosymbiont, acquired by ingestion of a red algal cell. Although the parasite has lost the capacity for photosynthesis, the plant-like nature of this signaling pathway may be exploited to develop new drugs. In support of this idea, an inhibitor of ABA biosynthesis protected mice against lethal infection with T. gondii. Here, we compare the role of ABA in parasites to its activities in plants, where it is know to control development and stress responses. PMID:19513200

  17. [Main parasitic skin disorders].

    PubMed

    Bernigaud, C; Monsel, G; Delaunay, P; Do-Pham, G; Foulet, F; Botterel, F; Chosidow, O

    2017-01-01

    Cutaneous parasitic skin diseases are frequent in human pathology. There are few reliable epidemiological data on the prevalence and/or incidence of such diseases. Skin parasites are cosmopolitan but their global distribution is heterogenous; prevalence is especially high in subtropical and tropical countries. They are mainly due to arthropods (insects and mites). Many species of parasites are involved, explaining the diversity of their clinical signs. The most common are caused by ectoparasites such as scabies or pediculosis (head lice, body lice and pubic lice). Clinical signs may be related to the penetration of the parasite under the skin, its development, the inoculation of venom or allergic symptoms. Diagnosis can be easy when clinical signs are pathognomonic (e.g. burrows in the interdigital web spaces in scabies) or sometimes more difficult. Some epidemiological characteristics (diurnal or nocturnal bite, seasonality) and specific clinical presentation (single or multiple bites, linear or grouped lesions) can be a great diagnostic help. Modern non-invasive tools (dermoscopy or confocal microscopy) will play an important role in the future but the eye and experience of the specialist (dermatologist, parasitologist, infectious disease specialist or entomologist) remains for the time the best way to guide or establish a diagnosis. For most skin parasites, therapeutic proposals are rarely based on studies of high level of evidence or randomized trials but more on expert recommendations or personal experience.

  18. Niche metabolism in parasitic protozoa

    PubMed Central

    Ginger, Michael L

    2005-01-01

    Complete or partial genome sequences have recently become available for several medically and evolutionarily important parasitic protozoa. Through the application of bioinformatics complete metabolic repertoires for these parasites can be predicted. For experimentally intractable parasites insight provided by metabolic maps generated in silico has been startling. At its more extreme end, such bioinformatics reckoning facilitated the discovery in some parasites of mitochondria remodelled beyond previous recognition, and the identification of a non-photosynthetic chloroplast relic in malarial parasites. However, for experimentally tractable parasites, mapping of the general metabolic terrain is only a first step in understanding how the parasite modulates its streamlined, yet still often puzzlingly complex, metabolism in order to complete life cycles within host, vector, or environment. This review provides a comparative overview and discussion of metabolic strategies used by several different parasitic protozoa in order to subvert and survive host defences, and illustrates how genomic data contribute to the elucidation of parasite metabolism. PMID:16553311

  19. Niche metabolism in parasitic protozoa.

    PubMed

    Ginger, Michael L

    2006-01-29

    Complete or partial genome sequences have recently become available for several medically and evolutionarily important parasitic protozoa. Through the application of bioinformatics complete metabolic repertoires for these parasites can be predicted. For experimentally intractable parasites insight provided by metabolic maps generated in silico has been startling. At its more extreme end, such bioinformatics reckoning facilitated the discovery in some parasites of mitochondria remodelled beyond previous recognition, and the identification of a non-photosynthetic chloroplast relic in malarial parasites. However, for experimentally tractable parasites, mapping of the general metabolic terrain is only a first step in understanding how the parasite modulates its streamlined, yet still often puzzlingly complex, metabolism in order to complete life cycles within host, vector, or environment. This review provides a comparative overview and discussion of metabolic strategies used by several different parasitic protozoa in order to subvert and survive host defences, and illustrates how genomic data contribute to the elucidation of parasite metabolism.

  20. Ecosystem consequences of fish parasites

    USGS Publications Warehouse

    Lafferty, Kevin D.

    2008-01-01

    In most aquatic ecosystems, fishes are hosts to parasites and, sometimes, these parasites can affect fish biology. Some of the most dramatic cases occur when fishes are intermediate hosts for larval parasites. For example, fishes in southern California estuaries are host to many parasites. The most common of these parasites, Euhaplorchis californiensis, infects the brain of the killifish Fundulus parvipinnis and alters its behaviour, making the fish 10–30 times more susceptible to predation by the birds that serve as its definitive host. Parasites like E. californiensis are embedded in food webs because they require trophic transmission. In the Carpinteria Salt Marsh estuarine food web, parasites dominate the links and comprise substantial amount of biomass. Adding parasites to food webs alters important network statistics such as connectance and nestedness. Furthermore, some free-living stages of parasites are food items for free-living species. For instance, fishes feed on trematode cercariae. Being embedded in food webs makes parasites sensitive to changes in the environment. In particular, fishing and environmental disturbance, by reducing fish populations, may reduce parasite populations. Indirect evidence suggests a decrease in parasites in commercially fished species over the past three decades. In addition, environmental degradation can affect fish parasites. For these reasons, parasites in fishes may serve as indicators of environmental impacts.

  1. Internal parasites of reptiles.

    PubMed

    Raś-Noryńska, Małgorzata; Sokół, Rajmund

    2015-01-01

    Nowadays a growing number of exotic reptiles are kept as pets. The aim of this study was to determine the species of parasites found in reptile patients of veterinary practices in Poland. Fecal samples obtained from 76 lizards, 15 turtles and 10 snakes were examined by flotation method and direct smear stained with Lugol's iodine. In 63 samples (62.4%) the presence of parasite eggs and oocysts was revealed. Oocysts of Isospora spp. (from 33% to 100% of the samples, depending on the reptilian species) and Oxyurids eggs (10% to 75%) were predominant. In addition, isolated Eimeria spp. oocysts and Giardia intestinalis cysts were found, as well as Strongylus spp. and Hymenolepis spp. eggs. Pet reptiles are often infected with parasites, some of which are potentially dangerous to humans. A routine parasitological examination should be done in such animals.

  2. Foodborne parasites from wildlife: how wild are they?

    PubMed

    Kapel, Christian M O; Fredensborg, Brian L

    2015-04-01

    The majority of wild foods consumed by humans are sourced from intensively managed or semi-farmed populations. Management practices inevitably affect wildlife density and habitat characteristics, which are key elements in the transmission of parasites. We consider the risk of transmission of foodborne parasites to humans from wildlife maintained under natural or semi-natural conditions. A deeper understanding will be useful in counteracting foodborne parasites arising from the growing industry of novel and exotic foods. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Foodborne protozoan parasites.

    PubMed

    Dawson, David

    2005-08-25

    This report addresses Cryptosporidium, Giardia, Cyclospora, and more briefly, Toxoplasma as the main parasitic protozoa of concern to food production worldwide. Other parasitic protozoa may be spread in food or water but are not considered as great a risk to food manufacture. The protozoan parasites Cryptosporidium, Giardia, and Cyclospora have proven potential to cause waterborne and foodborne disease. Toxoplasma gondii has been considered a risk in specific cases, but humans are not its primary host. Cryptosporidium and Giardia are widespread in the environment, particularly the aquatic environment, and major outbreaks of cryptosporidiosis and giardiasis have occurred as a result of contaminated drinking water. Large outbreaks of waterborne cyclosporiasis have not been identified. Cryptosporidium, Giardia, and Cyclospora have potential significance in the preparation and consumption of fresh produce and in catering practice, in which ready-to-eat foods may be served that have not received heat treatment. None of the three organisms Cryptosporidium, Giardia, and Cyclospora has been shown to be a problem for heat processed food or tap water that has undergone appropriate treatment at a water treatment works. All three are sensitive to standard pasteurisation techniques. Although humans are not a primary host for T. gondii, the potential exists for both waterborne and foodborne toxoplasmosis. Parasitic protozoa do not multiply in foods, but they may survive in or on moist foods for months in cool, damp environments. Their ecology makes control of these parasites difficult. For general control of parasitic protozoa in the food chain, the following steps are necessary: - Follow good hygienic practice in food service and catering industries.- Minimise dissemination of cysts and oocysts in the farming environment and via human waste management.- Include these microorganisms in Hazard Analysis Critical Control Point (HACCP) plans of water suppliers, industries or sectors

  4. Malaria Parasites: The Great Escape

    PubMed Central

    Rénia, Laurent; Goh, Yun Shan

    2016-01-01

    Parasites of the genus Plasmodium have a complex life cycle. They alternate between their final mosquito host and their intermediate hosts. The parasite can be either extra- or intracellular, depending on the stage of development. By modifying their shape, motility, and metabolic requirements, the parasite adapts to the different environments in their different hosts. The parasite has evolved to escape the multiple immune mechanisms in the host that try to block parasite development at the different stages of their development. In this article, we describe the mechanisms reported thus far that allow the Plasmodium parasite to evade innate and adaptive immune responses. PMID:27872623

  5. Trichinella inflammatory myopathy: host or parasite strategy?

    PubMed Central

    2011-01-01

    The parasitic nematode Trichinella has a special relation with muscle, because of its unique intracellular localization in the skeletal muscle cell, completely devoted in morphology and biochemistry to become the parasite protective niche, otherwise called the nurse cell. The long-lasting muscle infection of Trichinella exhibits a strong interplay with the host immune response, mainly characterized by a Th2 phenotype. The aim of this review is to illustrate the role of the Th2 host immune response at the muscle level during trichinellosis in different experimental models, such as knock-out or immuno-modulated mice. In particular, in knock-out mice a crucial role of IL-10 is evident for the regulation of inflammation intensity. The muscular host immune response to Trichinella is partially regulated by the intestinal phase of the parasite which emphasizes the intensity of the following muscle inflammation compared with animals infected by synchronized injections of newborn larvae. In eosinophil-ablated mice such as PHIL and GATA-- animals it was observed that there was an increased NOS2 expression in macrophages, driven by higher IFN-γ release, thus responsible for muscle larva damage. Besides modulation of the intestinal stage of the infection, using recombinant IL-12, increases the muscular parasite burden delaying adult worm expulsion from the intestine. Furthermore, a Th1 adjuvant of bacterial origin called Helicobacter pylori neutrophil activating protein (HP-NAP), administered during the intestinal phase of trichinellosis, alters the Th2 dependent response at muscle level. All these data from the literature delineate then a mutual adaptation between parasite and host immune response in order to achieve a strategic compromise between two evolutionary forces pointed towards the survival of both species. PMID:21429196

  6. Microarray in parasitic infections

    PubMed Central

    Sehgal, Rakesh; Misra, Shubham; Anand, Namrata; Sharma, Monika

    2012-01-01

    Modern biology and genomic sciences are rooted in parasitic disease research. Genome sequencing efforts have provided a wealth of new biological information that promises to have a major impact on our understanding of parasites. Microarrays provide one of the major high-throughput platforms by which this information can be exploited in the laboratory. Many excellent reviews and technique articles have recently been published on applying microarrays to organisms for which fully annotated genomes are at hand. However, many parasitologists work on organisms whose genomes have been only partially sequenced. This review is mainly focused on how to use microarray in these situations. PMID:23508469

  7. Gastrointestinal Parasitic Infections

    PubMed Central

    Embil, Juan A.; Embil, John M.

    1988-01-01

    This article surveys the most important gastrointestinal parasites that affect humans. The modes of acquisition, pathology, epidemiology, diagnosis, and treatment are all briefly examined. Gastrointestinal parasites have become increasingly important in the differential diagnosis of gastrointestinal disease, as a result of a number of circumstances. These circumstances include: increasing travel to developing countries; increased numbers, for one reason or another, of immunocompromised individuals; increased consumption of raw or partially cooked ethnic delicacies; more crowding in day-care centres; increased immigration from developing countries; and an endemic pocket of individuals with certain unhygienic or unsanitary practices. PMID:21253148

  8. Parasitism and the evolutionary ecology of animal personality.

    PubMed

    Barber, Iain; Dingemanse, Niels J

    2010-12-27

    The ecological factors responsible for the evolution of individual differences in animal personality (consistent individual differences in the same behaviour across time and contexts) are currently the subject of intense debate. A limited number of ecological factors have been investigated to date, with most attention focusing on the roles of resource competition and predation. We suggest here that parasitism may play a potentially important, but largely overlooked, role in the evolution of animal personalities. We identify two major routes by which parasites might influence the evolution of animal personality. First, because the risk of acquiring parasites can be influenced by an individual's behavioural type, local parasite regimes may impose selection on personality traits and behavioural syndromes (correlations between personality traits). Second, because parasite infections have consequences for aspects of host 'state', parasites might induce the evolution of individual differences in certain types of host behaviour in populations with endemic infections. Also, because infection often leads to specific changes in axes of personality, parasite infections have the potential to decouple behavioural syndromes. Host-parasite systems therefore provide researchers with valuable tools to study personality variation and behavioural syndromes from a proximate and ultimate perspective.

  9. Maintenance of polymorphic females: do parasites play a role?

    PubMed

    Sánchez-Guillén, R A; Martínez-Zamilpa, S M J; Jiménez-Cortés, J G; Forbes, M R L; Córdoba-Aguilar, A

    2013-01-01

    The role of parasites in explaining maintenance of polymorphism is an unexplored research avenue. In odonates, female-limited color polymorphism (one female morph mimicking the conspecific male and one or more gynochromatic morphs) is widespread. Here we investigated whether parasitism contributes to color polymorphism maintenance by studying six species of female dimorphic damselflies using large databases of field-collected animals. We predicted that androchrome females (male mimics) would be more intensively parasitized than gynochrome females which is, according to previous studies, counterbalanced by the advantages of the former when evading male harassment compared to gynochrome females. Here we show that in Ischnura denticollis and Enallagma novahispaniae, androchrome females suffer from a higher degree of parasitism than gynochromatic females, and contrary to prediction, than males. Thus, our study has detected a correlation between color polymorphism and parasitic burden in odonates. This leads us to hypothesize that natural selection, via parasite pressure, can explain in part how androchrome and gynochrome female color morphs can be maintained. Both morphs may cope with parasites in a different way: given that androchrome females are more heavily parasitized, they may pay a higher fecundity costs, in comparison to gynochrome females.

  10. Parasitism and the evolutionary ecology of animal personality

    PubMed Central

    Barber, Iain; Dingemanse, Niels J.

    2010-01-01

    The ecological factors responsible for the evolution of individual differences in animal personality (consistent individual differences in the same behaviour across time and contexts) are currently the subject of intense debate. A limited number of ecological factors have been investigated to date, with most attention focusing on the roles of resource competition and predation. We suggest here that parasitism may play a potentially important, but largely overlooked, role in the evolution of animal personalities. We identify two major routes by which parasites might influence the evolution of animal personality. First, because the risk of acquiring parasites can be influenced by an individual's behavioural type, local parasite regimes may impose selection on personality traits and behavioural syndromes (correlations between personality traits). Second, because parasite infections have consequences for aspects of host ‘state’, parasites might induce the evolution of individual differences in certain types of host behaviour in populations with endemic infections. Also, because infection often leads to specific changes in axes of personality, parasite infections have the potential to decouple behavioural syndromes. Host–parasite systems therefore provide researchers with valuable tools to study personality variation and behavioural syndromes from a proximate and ultimate perspective. PMID:21078659

  11. Ranging behavior drives parasite richness: A more parsimonious hypothesis.

    PubMed

    Bicca-Marques, Júlio César; Calegaro-Marques, Cláudia

    2016-09-01

    Parasitism is a ubiquitous interspecific interaction that may play an important role in the evolution of hosts and parasites, molding many aspects of their behavior and ecology. Detecting behavioral changes of hosts infected with parasites is not a straightforward task. Extrapolating from individual-level responses to group-level decision-making is still a much more complex challenge. The ranging behavior of hosts that live in social groups is a good example. Many hypotheses of the cause-effect relationship between this behavior and parasite diversity and load have been proposed. For instance, Brockmeyer et al. [2015, Am. J. Primatol. 77:1036-1048] recently suggested that the richness of protozoan parasites influences the daily path length of free-ranging mandrills. We believe that this explanation for the relationship contains several implicit assumptions. Therefore, we offer an alternative, more parsimonious hypothesis in which daily path length is the driver of parasite richness rather than its consequence. Our hypothesis only assumes that ranging farther exposes animals to a richer parasite diversity. We discuss the data required to test these alternative hypotheses and recall empirical evidence and theoretical modeling results supporting or rejecting their assumptions. We also propose a model of the expected outcomes in terms of species richness, load, intensity of infection, and within-group community similarity of non-lethal environmentally transmitted parasites in social animal groups showing distinct patterns of range use. Am. J. Primatol. 78:923-927, 2016. © 2016 Wiley Periodicals, Inc.

  12. Parasite responses to large mammal loss in an African savanna.

    PubMed

    Weinstein, Sara; Titcomb, Georgia; Agwanda, Bernard; Riginos, Corinna; Young, Hillary

    2017-04-12

    Biodiversity loss can alter disease transmission; however, the magnitude and direction of these effects vary widely across ecosystems, scales, and pathogens. Here we experimentally examine the effects of one of the most globally pervasive patterns of biodiversity decline, the selective loss of large wildlife, on infection probability, intensity and population size of a group of common rodent-borne parasites - macroparasitic helminths. Consistent with previous work on vector-borne pathogens, we found that large wildlife removal causes strong and systematic increases of rodent-borne parasites, largely due to increases in rodent density, as rodents are released from competition with larger herbivores. Although we predicted that increased host density would also increase per capita infection among all directly transmitted parasites, this additional amplification occurred for only 2 of 3 examined parasites. Furthermore, the actual effects of large mammal loss on per capita infection were mediated by the complex suite of abiotic and biotic factors that regulate parasite transmission. Thus, while these results strongly suggest that large wildlife loss will cause systematic increases in rodent parasite populations, they also underscore the difficulty of making more specific predictions for a given parasite based on simple attributes such as transmission mode or life history strategy. Instead, detailed information on the ecology of each parasite species would be necessary to make more accurate predictions of how biodiversity loss will affect infection. This article is protected by copyright. All rights reserved.

  13. On biomass of parasitic plants

    NASA Astrophysics Data System (ADS)

    He, J. H.; Mo, L.-F.

    2008-02-01

    An extremely simple and elementary but rigorous derivation of maximal biomass of parasitic plants is given using an assumption that metabolic rate of the parasite should not be larger than that of its host organ

  14. Past Intestinal Parasites.

    PubMed

    Le Bailly, Matthieu; Araújo, Adauto

    2016-08-01

    This chapter aims to provide some key points for researchers interested in the study of ancient gastrointestinal parasites. These few pages are dedicated to my colleague and friend, Prof. Adauto Araújo (1951-2015), who participated in the writing of this chapter. His huge efforts in paleoparasitology contributed to the development and promotion of the discipline during more than 30 years.

  15. Genomics of apicomplexan parasites.

    PubMed

    Swapna, Lakshmipuram Seshadri; Parkinson, John

    2017-02-22

    The increasing prevalence of infections involving intracellular apicomplexan parasites such as Plasmodium, Toxoplasma, and Cryptosporidium (the causative agents of malaria, toxoplasmosis, and cryptosporidiosis, respectively) represent a significant global healthcare burden. Despite their significance, few treatments are available; a situation that is likely to deteriorate with the emergence of new resistant strains of parasites. To lay the foundation for programs of drug discovery and vaccine development, genome sequences for many of these organisms have been generated, together with large-scale expression and proteomic datasets. Comparative analyses of these datasets are beginning to identify the molecular innovations supporting both conserved processes mediating fundamental roles in parasite survival and persistence, as well as lineage-specific adaptations associated with divergent life-cycle strategies. The challenge is how best to exploit these data to derive insights into parasite virulence and identify those genes representing the most amenable targets. In this review, we outline genomic datasets currently available for apicomplexans and discuss biological insights that have emerged as a consequence of their analysis. Of particular interest are systems-based resources, focusing on areas of metabolism and host invasion that are opening up opportunities for discovering new therapeutic targets.

  16. A Passion for Parasites

    PubMed Central

    Englund, Paul T.

    2014-01-01

    I knew nothing and had thought nothing about parasites until 1971. In fact, if you had asked me before then, I might have commented that parasites were rather disgusting. I had been at the Johns Hopkins School of Medicine for three years, and I was on the lookout for a new project. In 1971, I came across a paper in the Journal of Molecular Biology by Larry Simpson, a classmate of mine in graduate school. Larry's paper described a remarkable DNA structure known as kinetoplast DNA (kDNA), isolated from a parasite. kDNA, the mitochondrial genome of trypanosomatids, is a DNA network composed of several thousand interlocked DNA rings. Almost nothing was known about it. I was looking for a project on DNA replication, and I wanted it to be both challenging and important. I had no doubt that working with kDNA would be a challenge, as I would be exploring uncharted territory. I was also sure that the project would be important when I learned that parasites with kDNA threaten huge populations in underdeveloped tropical countries. Looking again at Larry's paper, I found the electron micrographs of the kDNA networks to be rather beautiful. I decided to take a chance on kDNA. Little did I know then that I would devote the next forty years of my life to studying kDNA replication. PMID:25336639

  17. Ungulate malaria parasites

    PubMed Central

    Templeton, Thomas J.; Asada, Masahito; Jiratanh, Montakan; Ishikawa, Sohta A.; Tiawsirisup, Sonthaya; Sivakumar, Thillaiampalam; Namangala, Boniface; Takeda, Mika; Mohkaew, Kingdao; Ngamjituea, Supawan; Inoue, Noboru; Sugimoto, Chihiro; Inagaki, Yuji; Suzuki, Yasuhiko; Yokoyama, Naoaki; Kaewthamasorn, Morakot; Kaneko, Osamu

    2016-01-01

    Haemosporida parasites of even-toed ungulates are diverse and globally distributed, but since their discovery in 1913 their characterization has relied exclusively on microscopy-based descriptions. In order to bring molecular approaches to bear on the identity and evolutionary relationships of ungulate malaria parasites, we conducted Plasmodium cytb-specific nested PCR surveys using blood from water buffalo in Vietnam and Thailand, and goats in Zambia. We found that Plasmodium is readily detectable from water buffalo in these countries, indicating that buffalo Plasmodium is distributed in a wider region than India, which is the only area in which buffalo Plasmodium has been reported. Two types (I and II) of Plasmodium sequences were identified from water buffalo and a third type (III) was isolated from goat. Morphology of the parasite was confirmed in Giemsa-reagent stained blood smears for the Type I sample. Complete mitochondrial DNA sequences were isolated and used to infer a phylogeny in which ungulate malaria parasites form a monophyletic clade within the Haemosporida, and branch prior to the clade containing bird, lizard and other mammalian Plasmodium. Thus it is likely that host switching of Plasmodium from birds to mammals occurred multiple times, with a switch to ungulates independently from other mammalian Plasmodium. PMID:26996979

  18. Parasitic Diseases With Cutaneous Manifestations.

    PubMed

    Ash, Mark M; Phillips, Charles M

    2016-01-01

    Parasitic diseases result in a significant global health burden. While often thought to be isolated to returning travelers, parasitic diseases can also be acquired locally in the United States. Therefore, clinicians must be aware of the cutaneous manifestations of parasitic diseases to allow for prompt recognition, effective management, and subsequent mitigation of complications. This commentary also reviews pharmacologic treatment options for several common diseases.

  19. Patterns in abundance and diversity of faecally dispersed parasites of tiger in Tadoba National Park, central India

    PubMed Central

    Marathe, Rahul R; Goel, Shantanu S; Ranade, Sachin P; Jog, Maithili M; Watve, Milind G

    2002-01-01

    Background Importance of parasites in ecological and evolutionary interactions is being increasingly recognized. However, ecological data on parasites of important host species is still scanty. We analyze the patterns seen in the faecal parasites of tigers in the Tadoba National Park, India, and speculate on the factors and processes shaping the parasite community and the possible implications for tiger ecology. Results The prevalence and intensities were high and the parasite community was dominated by indirect life cycle parasites. Across all genera of parasites variance scaled with the square of the mean and there was a significant positive correlation between prevalence and abundance. There was no significant association between different types of parasites. Conclusions The 70 samples analyzed formed 14 distinct clusters. If we assume each of the clusters to represent individual tigers that were sampled repeatedly and that resident tigers are more likely to be sampled repeatedly, the presumed transient tigers had significantly greater parasite loads than the presumed resident ones. PMID:12000685

  20. microRNAs in parasites and parasite infection

    PubMed Central

    Zheng, Yadong; Cai, Xuepeng; Bradley, Janette E.

    2013-01-01

    miRNAs, a subclass of small regulatory RNAs, are present from ancient unicellular protozoans to parasitic helminths and parasitic arthropods. The miRNA-silencing mechanism appears, however, to be absent in a number of protozoan parasites. Protozoan miRNAs and components of their silencing machinery possess features different from other eukaryotes, providing some clues on the evolution of the RNA-induced silencing machinery. miRNA functions possibly associate with neoblast biology, development, physiology, infection and immunity of parasites. Parasite infection can alter host miRNA expression that can favor both parasite clearance and infection. miRNA pathways are, thus, a potential target for the therapeutic control of parasitic diseases. PMID:23392243

  1. microRNAs in parasites and parasite infection.

    PubMed

    Zheng, Yadong; Cai, Xuepeng; Bradley, Janette E

    2013-03-01

    miRNAs, a subclass of small regulatory RNAs, are present from ancient unicellular protozoans to parasitic helminths and parasitic arthropods. The miRNA-silencing mechanism appears, however, to be absent in a number of protozoan parasites. Protozoan miRNAs and components of their silencing machinery possess features different from other eukaryotes, providing some clues on the evolution of the RNA-induced silencing machinery. miRNA functions possibly associate with neoblast biology, development, physiology, infection and immunity of parasites. Parasite infection can alter host miRNA expression that can favor both parasite clearance and infection. miRNA pathways are, thus, a potential target for the therapeutic control of parasitic diseases.

  2. Selective predation and productivity jointly drive complex behavior in host-parasite systems.

    PubMed

    Hall, Spencer R; Duffy, Meghan A; Cáceres, Carla E

    2005-01-01

    Successful invasion of a parasite into a host population and resulting host-parasite dynamics can depend crucially on other members of a host's community such as predators. We do not fully understand how predation intensity and selectivity shape host-parasite dynamics because the interplay between predator density, predator foraging behavior, and ecosystem productivity remains incompletely explored. By modifying a standard susceptible-infected model, we show how productivity can modulate complex behavior induced by saturating and selective foraging behavior of predators in an otherwise stable host-parasite system. When predators strongly prefer parasitized hosts, the host-parasite system can oscillate, but predators can also create alternative stable states, Allee effects, and catastrophic extinction of parasites. In the latter three cases, parasites have difficulty invading and/or persisting in ecosystems. When predators are intermediately selective, these more complex behaviors become less important, but the host-parasite system can switch from stable to oscillating and then back to stable states along a gradient of predator control. Surprisingly, at higher productivity, predators that neutrally select or avoid parasitized hosts can catalyze extinction of both hosts and parasites. Thus, synergy between two enemies can end disastrously for the host. Such diverse outcomes underscore the crucial importance of the community and ecosystem context in which host-parasite interactions occur.

  3. Metazoan Parasites of Antarctic Fishes.

    PubMed

    Oğuz, Mehmet Cemal; Tepe, Yahya; Belk, Mark C; Heckmann, Richard A; Aslan, Burçak; Gürgen, Meryem; Bray, Rodney A; Akgül, Ülker

    2015-06-01

    To date, there have been nearly 100 papers published on metazoan parasites of Antarctic fishes, but there has not yet been any compilation of a species list of fish parasites for this large geographic area. Herein, we provide a list of all documented occurrences of monogenean, cestode, digenean, acanthocephalan, nematode, and hirudinean parasites of Antarctic fishes. The list includes nearly 250 parasite species found in 142 species of host fishes. It is likely that there are more species of fish parasites, which are yet to be documented from Antarctic waters.

  4. Role of parasites in cancer.

    PubMed

    Mandong, B M; Ngbea, J A; Raymond, Vhriterhire

    2013-01-01

    In areas of parasitic endemicity, the occurrence of cancer that is not frequent may be linked with parasitic infection. Epidemiological correlates between some parasitic infections and cancer is strong, suggesting a strong aetiological association. The common parasites associated with human cancers are schistosomiasis, malaria, liver flukes (Clonorchis sinenses, Opistorchis viverrini). To review the pathology, literature and methods of diagnosis. Literature review from peer reviewed Journals cited in PubMed and local journals. Parasites may serve as promoters of cancer in endemic areas of infection.

  5. [Metazoan parasites of bream (Abramis brama Linnaeus, 1758) in Lake Durusu (Terkos)].

    PubMed

    Karatoy, Emine; Soylu, Erhan

    2006-01-01

    In this study, metazoan parasites of bream (Abramis brama Linnaeus, 1758) in the Lake Durusu (Terkos) were investigated between June 2002 and May 2003. During this study, a total of 67 bream were examined for the presence of metazoan parasites. Ten species of parasites were found on 64 of the 67 fish examined. These parasites are: Dactylogyrus sphyrna (Linstow, 1878) and D. distinguendus (Nybelin, 1936) Monogenoidea, Caryophyllaeus laticeps (Pallas, 1781) Cestoidea, Tetracotyle sp, Diplostomum sp. and Tylodelphys clavata (Nordmann, 1832) metacercaria Trematoda, Eustrongylides excisus (Jagerskiöld, 1909) Nematoda, Piscicola geometra (Linnaeus, 1758) Hirudinea, glochidia of mollusk, Bivalvia, Argulus foliaceus (L., 1758) Crustacea. Diplostomum sp., Dactylogyrus sphyrna and D. distinguendus were found to be the dominant parasites of A. brama. Both the prevalence and intensity of other parasites were not found to be high. All identified parasites are a new finding for A. brama in the Lake Durusu. This is the first time that D. distinguendus has been identified in Turkey.

  6. Harvest Regimens to Maximize Sericea Lespedeza Crude Protein and Condensed Tannins

    USDA-ARS?s Scientific Manuscript database

    Sericea lespedeza (SL; Lespedeza cuneata) is sold as hay or pellets for its crude protein (CP) and condensed tannin (CT) content, the latter to promote rumen bypass protein, depress methane emissions in livestock, and suppress gastro-intestinal parasites in small ruminants. Maximizing these forage c...

  7. Parasite transmission through suspension feeding.

    PubMed

    Ben-Horin, Tal; Bidegain, Gorka; Huey, Lauren; Narvaez, Diego A; Bushek, David

    2015-10-01

    Suspension-feeding bivalve molluscs are confronted with a wide range of materials in the benthic marine environment. These materials include various sized plankton and the organic material derived from it, macroalgae, detritus and a diversity of microbial parasites that have adapted life stages to survive in the water column. For bivalve parasites to infect hosts though, they must first survive and remain infectious in the water column to make initial contact with hosts, and once in contact, enter and overcome elaborate pathways for particle sorting and selection. Even past these defenses, bivalve parasites are challenged with efficient systems of mechanical and chemical digestion and highly evolved systems of innate immunity. Here we review how bivalve parasites evade these hurdles to complete their life cycles and establish within bivalve hosts. We broadly cover significant viral, bacterial, and protozoan parasites of marine bivalve molluscs, and illustrate the emergent properties of these host-parasite systems where parasite transmission occurs through suspension feeding.

  8. Protein moonlighting in parasitic protists.

    PubMed

    Ginger, Michael L

    2014-12-01

    Reductive evolution during the adaptation to obligate parasitism and expansions of gene families encoding virulence factors are characteristics evident to greater or lesser degrees in all parasitic protists studied to date. Large evolutionary distances separate many parasitic protists from the yeast and animal models upon which classic views of eukaryotic biochemistry are often based. Thus a combination of evolutionary divergence, niche adaptation and reductive evolution means the biochemistry of parasitic protists is often very different from their hosts and to other eukaryotes generally, making parasites intriguing subjects for those interested in the phenomenon of moonlighting proteins. In common with other organisms, the contribution of protein moonlighting to parasite biology is only just emerging, and it is not without controversy. Here, an overview of recently identified moonlighting proteins in parasitic protists is provided, together with discussion of some of the controversies.

  9. Surface activity of Corophium volutator: A role for parasites?

    NASA Astrophysics Data System (ADS)

    Damsgaard, Jacob Tørring; Mouritsen, Kim N.; Jensen, K. Thomas

    2005-08-01

    In soft-bottom intertidal habitats, the normally infaunal amphipod Corophium volutator is often found active on the sediment surface during low tide, exposed to desiccation and shorebird predation. Here we examine whether such risky behaviour is related to parasite infections. Surface-active and buried C. volutator were collected during a low tide period in the Danish Wadden Sea, and the infection patterns of the two groups were described in relation to sex and size. Surface-active males and females were more heavily infested by microphallid trematodes (four species) than buried specimens of the same sex and size class. Although the density of surfaced amphipods decreased as a function of exposure time, the mean parasite load of those that remained on the surface increased. A narrow size-specific parasite intensity threshold above which the amphipods were always surface active did not exist: heavily infected individuals were also found buried in the substrate. Although likely to be beneficial to the parasites, this suggests that the behavioural alteration is a side-effect of the infections rather than a consequence of direct parasitic manipulation. Besides the presumed mortality associated with the parasite-related surface activity in a range of size-classes, the intensity-size frequency distribution indicated that larger and hence heavily infected hosts are removed from the population. Together it demonstrates that microphallid trematodes impact the population dynamics of C. volutator.

  10. Peroxisomes in parasitic protists.

    PubMed

    Gabaldón, Toni; Ginger, Michael L; Michels, Paul A M

    Representatives of all major lineages of eukaryotes contain peroxisomes with similar morphology and mode of biogenesis, indicating a monophyletic origin of the organelles within the common ancestor of all eukaryotes. Peroxisomes originated from the endoplasmic reticulum, but despite a common origin and shared morphological features, peroxisomes from different organisms show a remarkable diversity of enzyme content and the metabolic processes present can vary dependent on nutritional or developmental conditions. A common characteristic and probable evolutionary driver for the origin of the organelle is an involvement in lipid metabolism, notably H2O2-dependent fatty-acid oxidation. Subsequent evolution of the organelle in different lineages involved multiple acquisitions of metabolic processes-often involving retargeting enzymes from other cell compartments-and losses. Information about peroxisomes in protists is still scarce, but available evidence, including new bioinformatics data reported here, indicate striking diversity amongst free-living and parasitic protists from different phylogenetic supergroups. Peroxisomes in only some protists show major involvement in H2O2-dependent metabolism, as in peroxisomes of mammalian, plant and fungal cells. Compartmentalization of glycolytic and gluconeogenic enzymes inside peroxisomes is characteristic of kinetoplastids and diplonemids, where the organelles are hence called glycosomes, whereas several other excavate parasites (Giardia, Trichomonas) have lost peroxisomes. Amongst alveolates and amoebozoans patterns of peroxisome loss are more complicated. Often, a link is apparent between the niches occupied by the parasitic protists, nutrient availability, and the absence of the organelles or their presence with a specific enzymatic content. In trypanosomatids, essentiality of peroxisomes may be considered for use in anti-parasite drug discovery. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Parasites and Foodborne Illness

    MedlinePlus

    ... Administrative Forms Standard Forms Skip Navigation Z7_0Q0619C0JGR010IFST1G5B10H1 Web Content Viewer (JSR 286) Actions ${title} Loading... / Topics / ... and Disease / Parasites and Foodborne Illness Z7_0Q0619C0JGR010IFST1G5B10H3 Web Content Viewer (JSR 286) Actions ${title} Loading... Z7_ ...

  12. Serodiagnosis of parasitic diseases.

    PubMed Central

    Maddison, S E

    1991-01-01

    In this review on serodiagnosis of parasitic diseases, antibody detection, antigen detection, use of monoclonal antibodies in parasitic serodiagnosis, molecular biological technology, and skin tests are discussed. The focus at the Centers for Disease Control on developing improved antigens, a truly quantitative FAST-enzyme-linked immunosorbent assay, and the very specific immunoblot assays for antibody detection is highlighted. The last two assays are suitable for field studies. Identification of patient response in terms of immunoglobulin class or immunoglobulin G subclass isotypes or both is discussed. Immunoglobulin isotypes may asist in defining the stage of some diseases. In other instances, use of a particular anti-isotype conjugate may increase the specificity of the assay. Monoclonal antibodies have played important roles in antigen purification and identification, in competitive antibody assays with increased sensitivity and specificity, and in assays for antigen detection in serum, body fluids, or excreta. Molecular biological technology has allowed significant advances in the production of defined parasitic serodiagnostic antigens. PMID:1747862

  13. Parasitic Myoma After Morcellation

    PubMed Central

    Sinha, Rakesh; Sundaram, Meenakshi; Lakhotia, Smita; Kadam, Pratima; Rao, Gayatri; Mahajan, Chaitali

    2009-01-01

    We report an interesting case of parasitic fibroid which developed from a morcellation remnant following laparoscopic myomectomy. The patient presented with incidental finding of pelvic mass in 2005. She underwent laparoscopic myomectomy for a myoma extending from the Pouch of Douglas to both sides of broad ligament. She subsequently presented with abdominal pain 3 years later in 2008. She underwent total laparoscopic hysterectomy with removal of broad ligament fibroids. During her hysterectomy, a right lumbar mass attached to the omentum was detected, which was excised laparoscopically. Histopathology of the mass confirmed it to be consistent with leiomyoma. This mass could probably be a morcellation remnant that has grown to this size taking blood supply from the omentum. We report this case to emphasize that all tissue pieces that are morcellated should be diligently removed. Even small bits displaced into the upper abdomen can result in parasitic fibroids. Thus, it can be concluded that parasitic myomas can arise from morcellated remnants and grow depending on the blood supply. PMID:22442523

  14. Human Parasites in Medieval Europe: Lifestyle, Sanitation and Medical Treatment.

    PubMed

    Mitchell, Piers D

    2015-01-01

    Parasites have been infecting humans throughout our evolution. However, not all people suffered with the same species or to the same intensity throughout this time. Our changing way of life has altered the suitability of humans to infection by each type of parasite. This analysis focuses upon the evidence for parasites from archaeological excavations at medieval sites across Europe. Comparison between the patterns of infection in the medieval period allows us to see how changes in sanitation, herding animals, growing and fertilizing crops, the fishing industry, food preparation and migration all affected human susceptibility to different parasites. We go on to explore how ectoparasites may have spread infectious bacterial diseases, and also consider what medieval medical practitioners thought of parasites and how they tried to treat them. While modern research has shown the use of a toilet decreases the risk of contracting certain intestinal parasites, the evidence for past societies presented here suggests that the invention of latrines had no observable beneficial effects upon intestinal health. This may be because toilets were not sufficiently ubiquitous until the last century, or that the use of fresh human faeces for manuring crops still ensured those parasite species were easily able to reinfect the population.

  15. Patterns of gregarine parasitism in dragonflies: host, habitat, and seasonality.

    PubMed

    Locklin, Jason L; Vodopich, Darrell S

    2010-06-01

    Gregarines are ubiquitous protozoan parasites that infect arthropods worldwide. More than 1,600 gregarine species have been described, but only a small percentage of invertebrates have been surveyed for these apicomplexan parasites. Adult dragonfly populations were surveyed for gregarines at two reservoirs in Texas, USA for 2 years. Gregarine prevalence and intensity were compared intraspecifically between host genders and reservoirs, among wing loads, and through time. Of the 29 dragonfly species collected, 41% hosted gregarines. Nine of these dragonfly species were previously undocumented as hosts. Among the commonly collected hosts, prevalence ranged from 18 to 52%. Parasites were aggregated among hosts and had a median intensity of five parasites per host. Gregarines were found only in hosts exceeding a minimum wing load, indicating that gregarines are likely not transferred from the naiad to adult during emergence. Prevalence and intensity increased during both years, suggesting that gregarine oocyst viability parallels increasing host population densities and may be short-lived. Prevalence and intensity also differed between dragonfly populations at two reservoirs. Regression analyses revealed that host species, host gender, month, and year were significant explanatory variables related to gregarine prevalence and intensity. Abundant information on odonate distributions, diversity, and mating activities makes dragonfly-gregarine systems excellent avenues for ecological, evolutionary, and parasitological research. Our results emphasize the importance of considering season, hosts, and habitat when studying gregarine-dragonfly ecology.

  16. Four-year monitoring of parasite communities in gobiid fishes of the southwest Baltic: III. parasite species diversity and applicability of monitoring.

    PubMed

    Zander, C Dieter

    2005-01-01

    The parasite infrapopulations of five goby species (Pomatoschistus minutus, P. pictus, P.microps, Gobiusculus flavescens and Gobius niger) were investigated during spring, summer and autumn of the years 1997-2000. In total, 34 parasite species were found: 17 Digenea, 6 Nematoda, 5 Cestoda, 3 Acanthocephala, 2 Protozoa, and 1 Monogenea. The dominant parasites were the digeneans Podocotyle atomon and Cryptocotyle concavum, which represent different ecological groups in terms of their modes of transmission, either indirectly by prey or directly by larvae. The relationship between the parasite Cryptocotyle concavum and the host P. microps is a special one which results in a mean intensity of several hundred cysts (max. 1,329) which settle in the kidney. The diversity of the parasite component community was highest in autumn, but low in spring and summer, with the exception of P. microps for which high values were already found in spring when direct parasites were disregarded. These results depend on the respective seasonal variation in species, some of which occur in huge numbers in some hosts. The diversity of the prey parasite assemblage is higher in Pomatoschistus microps and Gobius niger than in the whole parasite spectrum; the other hosts present the opposite trend. A combination of the island theory of biogeography as modified for parasite infection with the theory of screens and filters leads to a model which considers three handicaps or distances for parasite colonisation: genetic, phylogenetic and ecological. Long-term investigations, as performed here over a time-span of 4 years, can detect more than 80% of parasite species in single hosts after 3 years, and in the whole goby guild after 2 years. Long-term investigations can be useful for finding rare parasites, in analysing parasite diversity, and for determining the seasonality of parasites.

  17. Immunosenescence and resistance to parasite infection in the honey bee, Apis mellifera.

    PubMed

    Roberts, Katherine E; Hughes, William O H

    2014-09-01

    Immunosenescence, the systemic reduction of immune efficiency with age, is increasingly recognised as having important implications for host-parasite dynamics. Changes in the immune response can impact on the ability of an individual to resist or moderate parasite infection, depending on how and when it encounters a parasite challenge. Using the European honey bee Apis mellifera and its microsporidian parasite Nosema ceranae, we investigated the effects of host age on the ability to resist parasite infection and on baseline immunocompetence, assessed by quantifying constitutive (PO) and potential levels (PPO) of the phenoloxidase immune enzyme as general measures of immune function. There was a significant correlation between the level of general immune function and infection intensity, but not with survival, and changes in immune function with age correlated with the ability of individuals to resist parasite infection. Older individuals had better survival when challenged with a parasite than younger individuals, however they also had more intense infections and lower baseline immunocomptence. The ability of older individuals to have high infection intensities yet live longer, has potential consequences for parasite transmission. The results highlight the need to consider age in host-parasite studies and show the importance of choosing the correct measure when assaying invertebrate immunity.

  18. SEASONAL AND DEMOGRAPHIC FACTORS INFLUENCING GASTROINTESTINAL PARASITISM IN UNGULATES OF ETOSHA NATIONAL PARK

    PubMed Central

    Turner, Wendy C.; Getz, Wayne M.

    2011-01-01

    Host-parasite dynamics can be strongly affected by seasonality and age-related host immune responses. We investigated how observed variation in the prevalence and intensity of parasite egg or oocyst shedding in four co-occurring ungulate species may reflect underlying seasonal variation in transmission and host immunity. This study was conducted July 2005–October 2006 in Etosha National Park, Namibia, using indices of parasitism recorded from 1,022 fecal samples collected from plains zebra (Equus quagga), springbok (Antidorcas marsupialis), blue wildebeest (Connochaetes taurinus), and gemsbok (Oryx gazella). The presence and intensity of strongyle nematodes, Strongyloides spp. and Eimeria spp. parasites, were strongly seasonal for most host-parasite combinations, with more hosts infected in the wet season than the dry season. Strongyle intensity in zebra was significantly lower in juveniles than adults, and in springbok hosts, Eimeria spp. intensity was significantly greater in juveniles than adults. These results provide evidence that acquired immunity is less protective against strongyle nematodes than Eimeria spp. infections. The seasonal patterns in parasitism further indicate that the long dry season may limit development and survival of parasite stages in the environment and, as a result, host contact and parasite transmission. PMID:20966262

  19. Gray fox (Urocyon cinereoargenteus) parasite diversity in central Mexico.

    PubMed

    Hernández-Camacho, Norma; Pineda-López, Raúl Francisco; de Jesús Guerrero-Carrillo, María; Cantó-Alarcón, Germinal Jorge; Jones, Robert Wallace; Moreno-Pérez, Marco Antonio; Mosqueda-Gualito, Juan Joel; Zamora-Ledesma, Salvador; Camacho-Macías, Brenda

    2016-08-01

    Mexico has a long history of parasitological studies in communities of vertebrates. However, the mega diversity of the country makes fauna inventories an ongoing priority. Presently, there is little published on the parasite fauna of gray foxes (Urocyon cinereoargenteus Schereber, 1775) and this study provides new records of parasites for gray foxes in central Mexico. It is a continuation of a series of previous parasitological studies conducted with this carnivore in Mexico from 2003 to the present. A total of 24 foxes in the Parque Nacional El Cimatario (PANEC) were trapped, anaesthetized, and parasites recovered. The species found were Dirofilaria immitis, Ctenocephalides canis, C. felis, Euhoplopsillus glacialis affinis (first report for gray foxes in Mexico) Pulex simulants, and Ixodes sp. Three additional gray fox carcasses were necropsied and the parasites collected were adult nematodes Physaloptera praeputialis and Toxocara canis. The intensive study of the gray fox population selected for the 2013-2015 recent period allowed for a two-fold increase in the number of parasite species recorded for this carnivore since 2003 (nine to 18 parasite species), mainly recording parasitic arthropods, Dirofilaria immitis filariae and adult nematodes. The parasite species recorded are generalists that can survive in anthropic environments; which is characteristic of the present ecological scenario in central Mexico. The close proximity of the PANEC to the city of Santiago de Queretaro suggests possible parasite transmission between the foxes and domestic and feral dogs. Furthermore, packs of feral dogs in the PANEC might have altered habitat use by foxes, with possible impacts on transmission.

  20. Nutrition and parasite interaction.

    PubMed

    Coop, R L; Holmes, P H

    1996-01-01

    This overview focuses on the interaction between nutritional status and gastrointestinal nematode infection in ruminants and considers: (i) the influence of the parasite on host metabolism; and (ii) the effect of host nutrition on the establishment and survival of parasite populations, the development of the host-immune response and the pathophysiology of infection. Gastrointestinal nematodes reduce voluntary feed intake and efficiency of feed utilisation, a key feature being an increased endogenous loss of protein into the gastrointestinal tract. Overall there is movement of protein from productive processes into repair of the gastrointestinal tract, synthesis of plasma proteins and mucoprotein production. Although reduction in feed intake is a major factor contributing to the reduced performance of parasitised ruminants, the underlying mechanisms of the anorexia are poorly understood. Supplementation of the diet with additional protein does not appear to affect initial establishment of nematode infections but the pathophysiological consequences are generally more severe on lower planes of protein nutrition. The main effect of protein supplementation is to increase the rate of acquisition of immunity and increase resistance to reinfection and this has been associated with an enhanced cellular immune response in the gastrointestinal mucosa. The unresponsiveness of the young lamb can be improved by dietary protein supplementation. Recent trials have shown that growing sheep offered a free choice between a low and a high protein ration are able to modify their diet selection in order to alleviate the increase in protein requirements which result from gastrointestinal nematode infection. Studies on the influence of nutrition on the expression of genotype have shown that the benefits of a superior genotype are not lost on a low protein diet whereas a high protein diet can partially emeliorate the disadvantages of an inferior genotype. In addition to dietary protein

  1. [Emerging parasitic diseases].

    PubMed

    Weibel Galluzzo, C; Wagner, N; Michel, Y; Jackson, Y; Chappuis, F

    2014-05-07

    Travels, migration and circulation of goods facilitate the emergence of new infectious diseases often unrecognized outside endemic areas. Most of emerging infections are of viral origin. Muscular Sarcocystis infection, an acute illness acquired during short trips to Malaysia, and Chagas disease, a chronic illness with long incubation period found among Latin American migrants, are two very different examples of emerging parasitic diseases. The former requires a preventive approach for travelers going to Malaysia and must be brought forth when they return with fever, myalgia and eosinophilia, while the latter requires a proactive attitude to screen Latin American migrant populations that may face difficulties in accessing care.

  2. Immune Responses in Parasitic Diseases

    DTIC Science & Technology

    1982-09-01

    RESPONSES IN PARASITIC DISEASES Final Scientific Report Daniel J. Stechschulte, M.D. Herbert B. Lindsley, M.D. September 1982 (July 1974 - December 1979...REPORT & PERIOD COVERED IMMUNE RESPONSES IN PARASITIC DISEASES Final Report July 1977 - Dec. 1979 6. PERFORMING ORG. REPORT NUMBER S 4 7. AUTNIOR(a) 6...DAMD 17-74-C-4136 AD_______________ IMMUNE RESPONSES IN PARASITIC DISEASES Final Scientific Report Daniel J. Stechschulte, M.D. Herbert B. Lindsley

  3. Unexpected hosts: imaging parasitic diseases.

    PubMed

    Rodríguez Carnero, Pablo; Hernández Mateo, Paula; Martín-Garre, Susana; García Pérez, Ángela; Del Campo, Lourdes

    2017-02-01

    Radiologists seldom encounter parasitic diseases in their daily practice in most of Europe, although the incidence of these diseases is increasing due to migration and tourism from/to endemic areas. Moreover, some parasitic diseases are still endemic in certain European regions, and immunocompromised individuals also pose a higher risk of developing these conditions. This article reviews and summarises the imaging findings of some of the most important and frequent human parasitic diseases, including information about the parasite's life cycle, pathophysiology, clinical findings, diagnosis, and treatment. We include malaria, amoebiasis, toxoplasmosis, trypanosomiasis, leishmaniasis, echinococcosis, cysticercosis, clonorchiasis, schistosomiasis, fascioliasis, ascariasis, anisakiasis, dracunculiasis, and strongyloidiasis. The aim of this review is to help radiologists when dealing with these diseases or in cases where they are suspected. Teaching Points • Incidence of parasitic diseases is increasing due to migratory movements and travelling. • Some parasitic diseases are still endemic in certain regions in Europe. • Parasitic diseases can have complex life cycles often involving different hosts. • Prompt diagnosis and treatment is essential for patient management in parasitic diseases. • Radiologists should be able to recognise and suspect the most relevant parasitic diseases.

  4. [Parasitic dead-end: update].

    PubMed

    Magnaval, J F

    2006-08-01

    Parasitic dead-ends occur when a parasite is unable to establish a permanent interaction in an unnatural host. Although the likelihood of successful reproduction by the pathogenic agent is nul, parasitic dead-end heralds capture of new parasites and therefore expansion of the host range. Angiostrongyliasis due to A. cantonensis or A. costaricensis, anisakiasis, Ancylostoma caninum infection, gnathostomiasis and sparganosis are undoubtedly emerging zoonoses of particular medical interest. Prevention of these diseases relies on abstinence from eating raw meat from invertebrates or cold-blooded (poikilotherm) vertebrates (e.g. used in exotic dishes). These guidelines must be included in recommendations to travelers.

  5. From parasitism to mutualism: unexpected interactions between a cuckoo and its host.

    PubMed

    Canestrari, Daniela; Bolopo, Diana; Turlings, Ted C J; Röder, Gregory; Marcos, José M; Baglione, Vittorio

    2014-03-21

    Avian brood parasites lay eggs in the nests of other birds, which raise the unrelated chicks and typically suffer partial or complete loss of their own brood. However, carrion crows Corvus corone corone can benefit from parasitism by the great spotted cuckoo Clamator glandarius. Parasitized nests have lower rates of predation-induced failure due to production of a repellent secretion by cuckoo chicks, but among nests that are successful, those with cuckoo chicks fledge fewer crows. The outcome of these counterbalancing effects fluctuates between parasitism and mutualism each season, depending on the intensity of predation pressure.

  6. Trichinella spiralis: Adaptation and parasitism.

    PubMed

    Zarlenga, Dante; Wang, Zhengyuan; Mitreva, Makedonka

    2016-11-15

    Publication of the genome from the clade I organism, Trichinella spiralis, has provided us an avenue to address more holistic problems in parasitology; namely the processes of adaptation and the evolution of parasitism. Parasitism among nematodes has evolved in multiple, independent events. Deciphering processes that drive species diversity and adaptation are keys to understanding parasitism and advancing control strategies. Studies have been put forth on morphological and physiological aspects of parasitism and adaptation in nematodes; however, data is now coming available to investigate adaptation, host switching and parasitism at the genomic level. Herein we compare proteomic data from the clade I parasite, Trichinella spiralis with data from Brugia malayi (clade III), Meloidogyne hapla and Meloidogyne incognita (clade IV), and free-living nematodes belonging to the genera Caenorhabditis and Pristionchus (clade V). We explore changes in protein family birth/death and expansion/reduction over the course of metazoan evolution using Homo sapiens, Drosophila melanogaster and Saccharomyces cerevisiae as outgroups for the phylum Nematoda. We further examine relationships between these changes and the ability and/or result of nematodes adapting to their environments. Data are consistent with gene loss occurring in conjunction with nematode specialization resulting from parasitic worms acclimating to well-defined, environmental niches. We observed evidence for independent, lateral gene transfer events involving conserved genes that may have played a role in the evolution of nematode parasitism. In general, parasitic nematodes gained proteins through duplication and lateral gene transfer, and lost proteins through random mutation and deletions. Data suggest independent acquisition rather than ancestral inheritance among the Nematoda followed by selective gene loss over evolutionary time. Data also show that parasitism and adaptation affected a broad range of proteins

  7. Emerging food-borne parasites.

    PubMed

    Dorny, P; Praet, N; Deckers, N; Gabriel, S

    2009-08-07

    Parasitic food-borne diseases are generally underrecognised, however they are becoming more common. Globalization of the food supply, increased international travel, increase of the population of highly susceptible persons, change in culinary habits, but also improved diagnostic tools and communication are some factors associated with the increased diagnosis of food-borne parasitic diseases worldwide. This paper reviews the most important emerging food-borne parasites, with emphasis on transmission routes. In a first part, waterborne parasites transmitted by contaminated food such as Cyclospora cayetanensis, Cryptosporidium and Giardia are discussed. Also human fasciolosis, of which the importance has only been recognised in the last decades, with total numbers of reported cases increasing from less than 3000 to 17 million, is looked at. Furthermore, fasciolopsiosis, an intestinal trematode of humans and pigs belongs to the waterborne parasites as well. A few parasites that may be transmitted through faecal contamination of foods and that have received renewed attention, such as Toxoplasma gondii, or that are (re-)emerging, such as Trypanosoma cruzi and Echinococcus spp., are briefly reviewed. In a second part, meat-borne parasite infections are reviewed. Humans get infected by eating raw or undercooked meat infected with cyst stages of these parasites. Meat inspection is the principal method applied in the control of Taenia spp. and Trichinella spp. However, it is often not very sensitive, frequently not practised, and not done for T. gondii and Sarcocystis spp. Meat of reptiles, amphibians and fish can be infected with a variety of parasites, including trematodes (Opisthorchis spp., Clonorchis sinensis, minute intestinal flukes), cestodes (Diphyllobothrium spp., Spirometra), nematodes (Gnathostoma, spp., anisakine parasites), and pentastomids that can cause zoonotic infections in humans when consumed raw or not properly cooked. Another important zoonotic food

  8. Parasitic infection in various stages life of cultured Acipenser persicus

    PubMed Central

    Adel, Milad; Safari, Reza; Yaghoubzadeh, Zahra; Fazli, Hassan; Khalili, Elham

    2016-01-01

    The present study was conducted to evaluate the status of the parasite fauna in Acipenser persicus at different development stages, in order to find prevention protocols for parasitic diseases in this valuable species. For this purpose, sampling from each sex breeder, 10 egg samples, 5-day-old larvae (n = 20), 20-day-old larvae (n = 80) and fingerling of A. persicus (n = 60) released in earthen ponds were done. After the bioassay and preparing wet mount from the internal and external organs, identification was done according to the keys. According to the results, no fauna parasites were isolated from egg samples and 5-day-old larvae; but Trichodina spp. was isolated from 20-day-old larvae. Also, the same protozoan was isolated from fingerling released in earthen ponds, the mean intensity, prevalence and range of contamination by fingerling were higher with compared to 20-day-old larvae. Trichodina sp. and Diplostomum spathaceum were isolated from skin and eyes of females, respectively. However, Trichodina sp. and Ichthyophthirius multifiliis were isolated from skin of male breeders. In this study, no parasites were isolated from internal organs of larves and fingerling but four intestinal parasites included: Cucullanus sphaerocephlaus, Anisakis sp., Skyrjabinopsilus semiarmatus, and Lepto-rhynchoides plagicephalu were isolated from internal organs of breeder. Based on a wide range of parasitic infection observed in various life stages of A. persicus, it seems necessary to consider hygienic and management measures. PMID:27226891

  9. Parasitic infection in various stages life of cultured Acipenser persicus.

    PubMed

    Adel, Milad; Safari, Reza; Yaghoubzadeh, Zahra; Fazli, Hassan; Khalili, Elham

    2016-01-01

    The present study was conducted to evaluate the status of the parasite fauna in Acipenser persicus at different development stages, in order to find prevention protocols for parasitic diseases in this valuable species. For this purpose, sampling from each sex breeder, 10 egg samples, 5-day-old larvae (n = 20), 20-day-old larvae (n = 80) and fingerling of A. persicus (n = 60) released in earthen ponds were done. After the bioassay and preparing wet mount from the internal and external organs, identification was done according to the keys. According to the results, no fauna parasites were isolated from egg samples and 5-day-old larvae; but Trichodina spp. was isolated from 20-day-old larvae. Also, the same protozoan was isolated from fingerling released in earthen ponds, the mean intensity, prevalence and range of contamination by fingerling were higher with compared to 20-day-old larvae. Trichodina sp. and Diplostomum spathaceum were isolated from skin and eyes of females, respectively. However, Trichodina sp. and Ichthyophthirius multifiliis were isolated from skin of male breeders. In this study, no parasites were isolated from internal organs of larves and fingerling but four intestinal parasites included: Cucullanus sphaerocephlaus, Anisakis sp., Skyrjabinopsilus semiarmatus, and Lepto-rhynchoides plagicephalu were isolated from internal organs of breeder. Based on a wide range of parasitic infection observed in various life stages of A. persicus, it seems necessary to consider hygienic and management measures.

  10. Secondary metabolites in floral nectar reduce parasite infections in bumblebees.

    PubMed

    Richardson, Leif L; Adler, Lynn S; Leonard, Anne S; Andicoechea, Jonathan; Regan, Karly H; Anthony, Winston E; Manson, Jessamyn S; Irwin, Rebecca E

    2015-03-22

    The synthesis of secondary metabolites is a hallmark of plant defence against herbivores. These compounds may be detrimental to consumers, but can also protect herbivores against parasites. Floral nectar commonly contains secondary metabolites, but little is known about the impacts of nectar chemistry on pollinators, including bees. We hypothesized that nectar secondary metabolites could reduce bee parasite infection. We inoculated individual bumblebees with Crithidia bombi, an intestinal parasite, and tested effects of eight naturally occurring nectar chemicals on parasite population growth. Secondary metabolites strongly reduced parasite load, with significant effects of alkaloids, terpenoids and iridoid glycosides ranging from 61 to 81%. Using microcolonies, we also investigated costs and benefits of consuming anabasine, the compound with the strongest effect on parasites, in infected and uninfected bees. Anabasine increased time to egg laying, and Crithidia reduced bee survival. However, anabasine consumption did not mitigate the negative effects of Crithidia, and Crithidia infection did not alter anabasine consumption. Our novel results highlight that although secondary metabolites may not rescue survival in infected bees, they may play a vital role in mediating Crithidia transmission within and between colonies by reducing Crithidia infection intensities.

  11. Secondary metabolites in floral nectar reduce parasite infections in bumblebees

    PubMed Central

    Richardson, Leif L.; Adler, Lynn S.; Leonard, Anne S.; Andicoechea, Jonathan; Regan, Karly H.; Anthony, Winston E.; Manson, Jessamyn S.; Irwin, Rebecca E.

    2015-01-01

    The synthesis of secondary metabolites is a hallmark of plant defence against herbivores. These compounds may be detrimental to consumers, but can also protect herbivores against parasites. Floral nectar commonly contains secondary metabolites, but little is known about the impacts of nectar chemistry on pollinators, including bees. We hypothesized that nectar secondary metabolites could reduce bee parasite infection. We inoculated individual bumblebees with Crithidia bombi, an intestinal parasite, and tested effects of eight naturally occurring nectar chemicals on parasite population growth. Secondary metabolites strongly reduced parasite load, with significant effects of alkaloids, terpenoids and iridoid glycosides ranging from 61 to 81%. Using microcolonies, we also investigated costs and benefits of consuming anabasine, the compound with the strongest effect on parasites, in infected and uninfected bees. Anabasine increased time to egg laying, and Crithidia reduced bee survival. However, anabasine consumption did not mitigate the negative effects of Crithidia, and Crithidia infection did not alter anabasine consumption. Our novel results highlight that although secondary metabolites may not rescue survival in infected bees, they may play a vital role in mediating Crithidia transmission within and between colonies by reducing Crithidia infection intensities. PMID:25694627

  12. Do malaria parasites manipulate the escape behaviour of their avian hosts? An experimental study.

    PubMed

    Garcia-Longoria, Luz; Møller, Anders P; Balbontín, Javier; de Lope, Florentino; Marzal, Alfonso

    2015-12-01

    Escape behaviour is the behaviour that birds and other animals display when already caught by a predator. An individual exhibiting higher intensity of such anti-predator behaviour could have greater probabilities of escape from predators. Parasites are known to affect different aspects of host behaviour to increase their own fitness. Vector-transmitted parasites such as malaria parasites should gain by manipulating their hosts to enhance the probability of transmission. Several studies have shown that malaria parasites can manipulate their vectors leading to increased transmission success. However, little is known about whether malaria parasites can manipulate escape behaviour of their avian hosts thereby increasing the spread of the parasite. Here we used an experimental approach to explore if Plasmodium relictum can manipulate the escape behaviour of one of its most common avian hosts, the house sparrow Passer domesticus. We experimentally tested whether malaria parasites manipulate the escape behaviour of their avian host. We showed a decrease in the intensity of biting and tonic immobility after removal of infection with anti-malaria medication compared to pre-experimental behaviour. These outcomes suggest that infected sparrows performed more intense escape behaviour, which would increase the likelihood of individuals escaping from predators, but also benefit the parasite by increasing its transmission opportunities.

  13. Does interspecies hybridization affect the host specificity of parasites in cyprinid fish?

    PubMed

    Simková, Andrea; Dávidová, Martina; Papoušek, Ivo; Vetešník, Lukáš

    2013-04-12

    Host specificity varies among parasite species. Some parasites are strictly host-specific, others show a specificity for congeneric or non-congeneric phylogenetically related host species, whilst some others are non-specific (generalists). Two cyprinids, Cyprinus carpio and Carassius gibelio, plus their respective hybrids were investigated for metazoan parasites. The aim of this study was to analyze whether interspecies hybridization affects host specificity. The different degrees of host specificity within a phylogenetic framework were taken into consideration (i.e. strict specialist, intermediate specialist, and intermediate generalist). Fish were collected during harvesting the pond and identified using meristic traits and molecular markers. Metazoan parasite species were collected. Host specificity of parasites was determined using the following classification: strict specialist, intermediate specialist, intermediate generalist and generalist. Parasite species richness was compared between parental species and their hybrids. The effect of host species on abundance of parasites differing in host specificity was tested. Hybrids harbored more different parasite species but their total parasite abundance was lower in comparison with parental species. Interspecies hybridization affected the host specificity of ecto- and endoparasites. Parasite species exhibiting different degrees of host specificity for C. carpio and C. gibelio were also present in hybrids. The abundance of strict specialists of C. carpio was significantly higher in parental species than in hybrids. Intermediate generalists parasitizing C. carpio and C. gibelio as two phylogenetically closely related host species preferentially infected C. gibelio when compared to C. carpio, based on prevalence and maximum intensity of infection. Hybrids were less infected by intermediate generalists when compared to C. gibelio. This finding does not support strict co-adaptation between host and parasite genotypes

  14. Does interspecies hybridization affect the host specificity of parasites in cyprinid fish?

    PubMed Central

    2013-01-01

    Background Host specificity varies among parasite species. Some parasites are strictly host-specific, others show a specificity for congeneric or non-congeneric phylogenetically related host species, whilst some others are non-specific (generalists). Two cyprinids, Cyprinus carpio and Carassius gibelio, plus their respective hybrids were investigated for metazoan parasites. The aim of this study was to analyze whether interspecies hybridization affects host specificity. The different degrees of host specificity within a phylogenetic framework were taken into consideration (i.e. strict specialist, intermediate specialist, and intermediate generalist). Methods Fish were collected during harvesting the pond and identified using meristic traits and molecular markers. Metazoan parasite species were collected. Host specificity of parasites was determined using the following classification: strict specialist, intermediate specialist, intermediate generalist and generalist. Parasite species richness was compared between parental species and their hybrids. The effect of host species on abundance of parasites differing in host specificity was tested. Results Hybrids harbored more different parasite species but their total parasite abundance was lower in comparison with parental species. Interspecies hybridization affected the host specificity of ecto- and endoparasites. Parasite species exhibiting different degrees of host specificity for C. carpio and C. gibelio were also present in hybrids. The abundance of strict specialists of C. carpio was significantly higher in parental species than in hybrids. Intermediate generalists parasitizing C. carpio and C. gibelio as two phylogenetically closely related host species preferentially infected C. gibelio when compared to C. carpio, based on prevalence and maximum intensity of infection. Hybrids were less infected by intermediate generalists when compared to C. gibelio. Conclusions This finding does not support strict co

  15. Parasite communities in stray cat populations from Lisbon, Portugal.

    PubMed

    Waap, H; Gomes, J; Nunes, T

    2014-12-01

    Stray cats live in high-density colonies in urban areas and pose a health hazard to household cats and humans. In Portugal, information on the parasitic fauna of stray cats is limited and relies mostly on results from faecal analysis. The present survey aimed to determine the prevalence, diversity and intensity of parasites in stray cats from the urban area of Lisbon by means of parasitological necropsy. Internal organs were collected from 162 cats captured in different areas of the city and systematically subjected to parasitological dissection. Helminths were identified by macro- and microscopic examination and protozoa by faecal floatation and sedimentation techniques. The overall prevalence of parasites was 90.7% (95% confidence interval (CI): 85.3-94.6%). A total of 12 parasite species was recorded: Cystoisospora felis (14.2%), Cystoisospora rivolta (46.3%), Sarcocystis sp. (1.2%), Ancylostoma tubaeforme (19.1%), Toxocara cati (38.3%), Ollulanus tricuspis (30.9%), Aelurostrongylus abstrusus (12.4%), Eucoleus aerophilus (0.6%), Taenia taeniaeformis (3.1%), Dipylidium caninum (53.1%), Joyeuxiella pasqualei (15.4%) and Diplopylidium nölleri (3.7%). Overall mean species richness was 2.36 ±  1.52. Helminth mean intensity was highest for O. tricuspis (285.8), followed by D. caninum (42.4), J. pasqualei (14.4), A. tubaeforme (8.1) and T. cati (5.9). The prevalence and variety of parasites found in our sampling are substantially higher than the numbers previously reported in Portugal. Some of the parasites, including T. cati and A. tubaeforme, are zoonotic, which emphasizes the need for parasite control strategies based on demographic containment of stray cat populations in urban areas to promote public health protection.

  16. Extracellular vesicles in parasitic diseases

    PubMed Central

    Marcilla, Antonio; Martin-Jaular, Lorena; Trelis, Maria; de Menezes-Neto, Armando; Osuna, Antonio; Bernal, Dolores; Fernandez-Becerra, Carmen; Almeida, Igor C.; del Portillo, Hernando A.

    2014-01-01

    Parasitic diseases affect billions of people and are considered a major public health issue. Close to 400 species are estimated to parasitize humans, of which around 90 are responsible for great clinical burden and mortality rates. Unfortunately, they are largely neglected as they are mainly endemic to poor regions. Of relevance to this review, there is accumulating evidence of the release of extracellular vesicles (EVs) in parasitic diseases, acting both in parasite–parasite inter-communication as well as in parasite–host interactions. EVs participate in the dissemination of the pathogen and play a role in the regulation of the host immune systems. Production of EVs from parasites or parasitized cells has been described for a number of parasitic infections. In this review, we provide the most relevant findings of the involvement of EVs in intercellular communication, modulation of immune responses, involvement in pathology, and their potential as new diagnostic tools and therapeutic agents in some of the major human parasitic pathogens. PMID:25536932

  17. Root parasites of southern forests

    Treesearch

    Lytton J. Musselman; William F. Mann

    1978-01-01

    The five families of root parasites of the South are discussed relative to selection of hosts, ecology, and potential for damage to commercial species. An identification key to all genera of root parasites is included. Plants and flowers of 29 species are illustrated and their distribution in the South mapped.

  18. Parasitic Weeds, a Scientific Challenge

    USDA-ARS?s Scientific Manuscript database

    A recent issue of the SCI journal Pest Management Science (May, 2009) was devoted to an overview of the problem of parasitic weeds and to the research that is being done to alleviate it. These papers are from an OECD-sponsored conference entitled Managing Parasitic Weeds that recently brought the b...

  19. Helminth parasites of eastern box turtles (Terrapene carolina carolina) from southern Indiana, USA.

    PubMed

    Moraga, P; Kinsella, J M; Sepúlveda, M S

    2012-03-01

    Very little is known about parasitic diseases of eastern box turtles (Terrapene carolina carolina). The objective of this study was to examine the parasitic fauna of eastern box turtles collected from southern Indiana, USA. Turtles (n = 40) were salvaged mostly as road kills from southern Indiana between May and October 2009. Seven species of helminths in total were found parasitizing the gastrointestinal tract, including two digenean trematodes (Brachycoelium salamandrae and Telorchis robustus) and five nematodes (Oswaldocruzia pipiens, Cosmocercoides dukae, Falcaustra affinis, F. chelydrae and Serpinema trispinosus). We report prevalence, abundance and mean intensity of infection for all helminths. Helminths were not found in any other organs examined (heart, gonads, liver, heart, kidney and urinary bladder) and no ectoparasites were found. Overall, mean intensity of infections was low (1-14 parasites/host), suggesting that these parasites are unlikely to be associated with negative health impacts. This constitutes the first study of this kind for Indiana.

  20. Intra- and intersexual differences in parasite resistance and female fitness tolerance in a polymorphic insect

    PubMed Central

    Svensson, Erik I.

    2017-01-01

    To understand host–parasite interactions, it is necessary to quantify variation and covariation in defence traits. We quantified parasite resistance and fitness tolerance of a polymorphic damselfly (Ischnura elegans), an insect with three discrete female colour morphs but with monomorphic males. We quantified sex and morph differences in parasite resistance (prevalence and intensity of water mite infections) and morph-specific fitness tolerance in the females in natural populations for over a decade. There was no evidence for higher parasite susceptibility in males as a cost of sexual selection, whereas differences in defence mechanisms between female morphs are consistent with correlational selection operating on combinations of parasite resistance and tolerance. We suggest that tolerance differences between female morphs interact with frequency-dependent sexual conflict, which maintains the polymorphism locally. Host–parasite interactions can therefore shape intra- and intersexual phenotypic divergence and interfere with sexual selection and sexual conflict. PMID:28123090

  1. Malaria, microscopic view of cellular parasites (image)

    MedlinePlus

    Malaria is a disease caused by parasites that are carried by mosquitoes. Once in the bloodstream, the parasite inhabits the red blood cell (RBC). This picture shows purple-stained malaria parasites inside red blood cells.

  2. Serine Proteases of Parasitic Helminths

    PubMed Central

    Yang, Yong; Wen, Yun jun; Cai, Ya Nan; Vallée, Isabelle; Boireau, Pascal; Liu, Ming Yuan; Cheng, Shi Peng

    2015-01-01

    Serine proteases form one of the most important families of enzymes and perform significant functions in a broad range of biological processes, such as intra- and extracellular protein metabolism, digestion, blood coagulation, regulation of development, and fertilization. A number of serine proteases have been identified in parasitic helminths that have putative roles in parasite development and nutrition, host tissues and cell invasion, anticoagulation, and immune evasion. In this review, we described the serine proteases that have been identified in parasitic helminths, including nematodes (Trichinella spiralis, T. pseudospiralis, Trichuris muris, Anisakis simplex, Ascaris suum, Onchocerca volvulus, O. lienalis, Brugia malayi, Ancylostoma caninum, and Steinernema carpocapsae), cestodes (Spirometra mansoni, Echinococcus granulosus, and Schistocephalus solidus), and trematodes (Fasciola hepatica, F. gigantica, and Schistosoma mansoni). Moreover, the possible biological functions of these serine proteases in the endogenous biological phenomena of these parasites and in the host-parasite interaction were also discussed. PMID:25748703

  3. Protozoan Parasites of Bivalve Molluscs: Literature Follows Culture

    PubMed Central

    Fernández Robledo, José A.; Vasta, Gerardo R.; Record, Nicholas R.

    2014-01-01

    Bivalve molluscs are key components of the estuarine environments as contributors to the trophic chain, and as filter –feeders, for maintaining ecosystem integrity. Further, clams, oysters, and scallops are commercially exploited around the world both as traditional local shellfisheries, and as intensive or semi–intensive farming systems. During the past decades, populations of those species deemed of environmental or commercial interest have been subject to close monitoring given the realization that these can suffer significant decline, sometimes irreversible, due to overharvesting, environmental pollution, or disease. Protozoans of the genera Perkinsus, Haplosporidium, Marteilia, and Bonamia are currently recognized as major threats for natural and farmed bivalve populations. Since their identification, however, the variable publication rates of research studies addressing these parasitic diseases do not always appear to reflect their highly significant environmental and economic impact. Here we analyzed the peer– reviewed literature since the initial description of these parasites with the goal of identifying potential milestone discoveries or achievements that may have driven the intensity of the research in subsequent years, and significantly increased publication rates. Our analysis revealed that after initial description of the parasite as the etiological agent of a given disease, there is a time lag before a maximal number of yearly publications are reached. This has already taken place for most of them and has been followed by a decrease in publication rates over the last decade (20– to 30– year lifetime in the literature). Autocorrelation analyses, however, suggested that advances in parasite purification and culture methodologies positively drive publication rates, most likely because they usually lead to novel molecular tools and resources, promoting mechanistic studies. Understanding these trends should help researchers in prioritizing

  4. Protozoan parasites of bivalve molluscs: literature follows culture.

    PubMed

    Fernández Robledo, José A; Vasta, Gerardo R; Record, Nicholas R

    2014-01-01

    Bivalve molluscs are key components of the estuarine environments as contributors to the trophic chain, and as filter -feeders, for maintaining ecosystem integrity. Further, clams, oysters, and scallops are commercially exploited around the world both as traditional local shellfisheries, and as intensive or semi-intensive farming systems. During the past decades, populations of those species deemed of environmental or commercial interest have been subject to close monitoring given the realization that these can suffer significant decline, sometimes irreversible, due to overharvesting, environmental pollution, or disease. Protozoans of the genera Perkinsus, Haplosporidium, Marteilia, and Bonamia are currently recognized as major threats for natural and farmed bivalve populations. Since their identification, however, the variable publication rates of research studies addressing these parasitic diseases do not always appear to reflect their highly significant environmental and economic impact. Here we analyzed the peer- reviewed literature since the initial description of these parasites with the goal of identifying potential milestone discoveries or achievements that may have driven the intensity of the research in subsequent years, and significantly increased publication rates. Our analysis revealed that after initial description of the parasite as the etiological agent of a given disease, there is a time lag before a maximal number of yearly publications are reached. This has already taken place for most of them and has been followed by a decrease in publication rates over the last decade (20- to 30- year lifetime in the literature). Autocorrelation analyses, however, suggested that advances in parasite purification and culture methodologies positively drive publication rates, most likely because they usually lead to novel molecular tools and resources, promoting mechanistic studies. Understanding these trends should help researchers in prioritizing research

  5. Parasitism and Physiological Trade-Offs in Stressed Capybaras

    PubMed Central

    Eberhardt, Ayelen T.; Costa, Sebastián A.; Marini, M. Rocío; Racca, Andrea; Baldi, Cecilia J.; Robles, M. Rosario; Moreno, Pablo G.; Beldomenico, Pablo M.

    2013-01-01

    Parasites play a key role in regulating wildlife population dynamics, but their impact on the host appears to be context-dependent. Evidence indicates that a synergistic interaction between stress, host condition and parasites is implicated in this phenomenon, but more studies are needed to better understand this context-dependency. With the goal to assess the net effect of two types of chronic stress on various host-parasite interactions, we conducted an experiment in capybaras to evaluate the impact of food restriction and physical restraint on the infection intensity of specific gastrointestinal nematodes and coccidia, and how these stressors affected the growth, body condition, and some immuno-physiological parameters. Our hypothesis was that both forms of stress would result in an alteration in the host-parasite interactions, with deteriorated condition and reduced immunological investment leading to high parasite burdens and vice versa. Stressed capybaras had significantly higher coccidia infection intensities; but among individuals that were smaller, those stressed consistently showed lower helminth burdens than controls. Both stress treatments had a marked negative impact on growth and body condition, but concomitantly they had a significant positive effect on some components of the immune system. Our results suggest, on the one hand, that during prolonged periods of stress capybaras preventatively invest in some components of their immunity, such as innate humoural defenses and cells that combat helminths, which could be considered a stress-dependent prophylaxis. On the other hand, stress was found to cause greater infection intensities of protozoans but lower burdens of nematodes, indicating that the relationship between stress, physiological trade-offs and infection depends on the type of parasite in question. Moreover, both findings might be related in a causal way, as one of the immunological parameters enhanced in stressed capybaras is associated with

  6. [Parasitic factor and cancer].

    PubMed

    Khamidullin, R I; Aglullin, I R; Rakhmanin, Iu A; Pogorel'tsev, V I; Khamidullin, A R; Galkina, I V; Khamidullin, I R; Sultanaeva, E G

    2011-01-01

    There is opinion in the literature as to that liver trematode infections, such as opisthorchiasis, clonorchiasis, fascioliasis, and metorchiasis, can induce cancer of the liver pancreas, intestine - this all is clinically observed. The authors were the first in world practice to show the development of a hepatic blastomatous process in animals (albino rats, cats) with opisthorchiasis in 13%; cancer developed in 28 and 56% with the use of a hepatotropic carcinogen and combined (opisthorchiasis + a carcinogen) exposure, respectively. Throughout his life, a human being can easily catch these trematodes that have carcinogenic activity and these diseases concurrent with household and food carcinogens can give rise to tumors in the liver pancreas and intestine. Timely diagnosis and specific anthelmintic therapy are necessary to prevent parasitic cancer.

  7. Influence of pollution on parasites of aquatic animals.

    PubMed

    Khan, R A; Thulin, J

    1991-01-01

    We have tried to draw attention to an increasing body of evidence (from several publications) that parasites of fish might be useful indicators of pollution. Several types of pollutants, including domestic sewage, pesticides, polychlorinated biphenyls, heavy metals, pulp and paper effluents, petroleum aromatic hydrocarbons, acid rain, and others, are known to affect aquatic animals. Many of the latter are parasitized and, under natural environmental conditions, most fish parasites are believed to cause little or no harm. However, chronic exposure to pollutants over a period of time causes biochemical, physiological and behavioural host changes that ultimately can influence the prevalence and intensity of parasitism. Some of these changes include host nutrition, growth and reproduction. Macroscopic lesions might not always be apparent, but subtle disorders in several specific tissues and organs might occur. Pollutants might promote increased parasitism in aquatic animals, especially fish, by impairing the host's immune response or favouring the survival and reproduction of the intermediate hosts. Alternatively, decreased parasitism might ensue through toxicity of the pollutant to free-living stages and intermediate hosts or by alteration of the host's physiology. Experimental studies indicate that the numbers of ectoparasites such as trichodinid ciliates and monogeneans increase significantly on the gills following exposure to a pollutant, and this is supported by field data on other ciliates and monogeneans where evidence of pollution has been clearly demonstrated. There is also evidence that endoparasitic protozoons, such as myxozoons, microsporans and haematozoons, all of which are capable of proliferating in their hosts, increase substantially in prevalence and intensity when interacting with pollutants. The period of patency might also be prolonged in haematozoan infections. Most reports of pollution effects on endoparasites suggest increased parasitism in fish

  8. The prevalence of helminth parasites in Pelophylax nigromaculatus (Anura: Ranidae) from Shanghai, China.

    PubMed

    Men, Qifei; Han, Hongyu; Zhao, Qiping; Xia, Weili; Dong, Hui; Zhu, Shunhai; Wang, Ziwen; Li, Cong; Zhu, Xuelong; Huang, Bing

    2016-12-01

    Parasites are ubiquitous members of biotic communities. To investigate the infective status of helminth parasites in Pelophylax nigromaculatus from Shanghai, 90 frogs were collected from July 2013 to July 2014 and examined for the presence of internal parasites. Of these, 86.67% (78/90) of frogs were infected with parasites, the total helminth intensity within infected frogs ranged from 1 to 367, and the mean intensity was 28.49. The infection rates and intensities were 78.89% and 22.89 for trematodes, 50.00% and 5.24 for nematodes, 13.33% and 3.92 for cestodes, and 41.11% and 8.49 for acanthocephalas, respectively. The majority (60.04%) of parasites were parasitic in the intestine, followed by urinary bladder (24.8%) and lungs (7.38%). Based on morphological features, 13 different species of helminth, including 9 undetermined species, were identified. The infective status of different species was significantly different. The most prevalent species were Diplodiscus nigromaculati (64.44%), Diplodiscus sp. (37.78%), Pomphorhynchus sp. (35.56%), Strongyloides sp. (33.33%). The mean infection intensity of Diplorchis nigromaculatus (139.25) was higher than the others' species ranged from 3.57-14.63. This is the first reported discovery of Pomphorhynchus sp. (Pomphorhynchidae Yamaguti, 1939) in frogs from China. These data provide the foundation for further analyses of parasites in this and other species of amphibians.

  9. Arthropod parasites of the red-bellied squirrel Callosciurus erythraeus introduced into Argentina.

    PubMed

    Gozzi, A C; Guichón, M L; Benitez, V V; Lareschi, M

    2013-06-01

    The introduction of an exotic species usually modifies parasite-host dynamics by the import of new parasites or the exotic species' acquiral of local parasites. The loss of parasites may determine the outcome of an invasion if the introduced species is liberated from co-evolved parasites in its range of invasion. In addition, an introduced species may pose sanitary risks to humans and other mammals if it serves as a reservoir of pathogens or carries arthropod vectors. The red-bellied squirrel, Callosciurus erythraeus (Pallas) (Rodentia: Sciuridae), was introduced into Argentina in 1970, since when several foci of invasion have been closely associated with humans. Investigation of the parasitological fauna of C. erythraeus in Argentina will generate new information about novel parasite-host dynamics and may provide new insight into the reasons for the successful invasion of this species. The objective of this study was to describe the arthropod parasites of C. erythraeus in Argentina in comparison with previous studies of parasites of this species in its native habitat and in the ranges of its invasion. Occasional host-parasite associations with local arthropod parasites not previously described for C. erythraeus are reported; these include the mites Androlaelaps fahrenholzi (Ewing) (Mesostigmata: Laelapidae) and Ornithonyssus cf. bacoti (Mesostigmata: Macronyssidae), the flea Polygenis (Polygenis) rimatus Jordan (Siphonaptera: Rhopalopsyllidae) and the botfly Cuterebra Clark (Diptera: Oestridae: Cuterebrinae). Cheyletus sp. mites (Trombidiformes: Cheyletidae) were also found. The low prevalence and mean intensity of ectoparasite species may influence invasion dynamics. © 2012 The Royal Entomological Society.

  10. Potential interactions between metazoan parasites of the Mayan catfish Ariopsis assimilis and chemical pollution in Chetumal Bay, Mexico.

    PubMed

    Vidal-Martínez, V M; Aguirre-Macedo, M L; Noreña-Barroso, E; Gold-Bouchot, G; Caballero-Pinzón, P I

    2003-06-01

    The effect of pollutants on the intensity of infection of metazoan parasites in the Mayan catfish, Ariopsis assimilis was investigated. Data were collected on pollutants and metazoan parasites from 76 catfish from five localities in Chetumal Bay in October, 1996. Nineteen pollutants (pesticides, polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs)) were found in the catfish livers. Heavy metal content was not determined. Nineteen metazoan parasite species were recovered. After controlling for fish length and sampling station, there was a significant negative linear relationship between the intensity of the larval digenean Mesostephanus appendiculatoides and 1,1,1,-trichloro-2,2-bis (4-chlorophenyl) ethane (DDT) concentrations. This negative relationship may be explained either by the effect of the pesticide on the mortality of (i) free-living larval forms, (ii) metacercariae in the fish, (iii) infected fish or (iv) intermediate host snails. There were significant differences between fish parasitized and not parasitized with M. appendiculatoides with respect to their DDT concentrations. There were also significant differences between the variances of the mean Clark's coefficient of condition values between catfish parasitized and not parasitized by M. appendiculatoides, with the variance of non-parasitized catfish being significantly larger. The results provided statistical evidence that DDT has a detrimental effect on M. appendiculatoides infection intensity. Furthermore, the significantly larger variance value of Clark's coefficient for non-parasitized fish suggested that DDT affects both the parasite and general host condition.

  11. Influence of Massive and Long Distance Migration on Parasite Epidemiology: Lessons from the Great Wildebeest Migration.

    PubMed

    Mijele, Domnic; Iwaki, Takashi; Chiyo, Patrick I; Otiende, Moses; Obanda, Vincent; Rossi, Luca; Soriguer, Ramon; Angelone-Alasaad, Samer

    2016-12-01

    Very little is known about the influence of massive and long distance migration on parasite epidemiology. Migration can simultaneously minimize exposure to common parasites in their habitats and increase exposure to novel pathogens from new environments and habitats encountered during migration, while physiological stress during long distance movement can lead to immune suppression, which makes migrants vulnerable to parasites. In this paper, we investigated the diversity, prevalence, parasite load, co-infection patterns and predilection sites of adult gastrointestinal helminths in 130 migrating wildebeests and tested for their relation with animal age, sex and migration time (which also could indicate different migration routes), and compared them with the non-migratory wildebeest. Surprisingly, only four parasite species were found, Oesophagostomum columbianum, Haemonchus placei, Calicophoron raja and Moniezia expansa, which were lower than in non-migratory wildebeest reported in the literature. These parasites were generalists, infecting livestock, and suggests that wildebeest and livestock, because of their interaction during migration, have a cross-infection risk. There was a negative relation between parasites diversity, prevalence and intensity of infection, and host age, which suggests that wildebeests acquire protective immunity against these parasites as they get older. Prevalence and intensity of infection were higher among wildebeest crossing the Mara Bridge (early migrants) compared to those crossing the Serena (late migrants), which suggests that early migrants (or migrants originating from different areas) have varying infection intensities. The prevalence and intensity of infection were higher in males compared to females and may be due to ecological, behavioural, or physiological differences between males and females. Our findings compared to those of previous studies suggest that migration may provide a mechanism to minimize exposure of hosts to

  12. Enemies with benefits: parasitic endoliths protect mussels against heat stress

    NASA Astrophysics Data System (ADS)

    Zardi, G. I.; Nicastro, K. R.; McQuaid, C. D.; Ng, T. P. T.; Lathlean, J.; Seuront, L.

    2016-08-01

    Positive and negative aspects of species interactions can be context dependant and strongly affected by environmental conditions. We tested the hypothesis that, during periods of intense heat stress, parasitic phototrophic endoliths that fatally degrade mollusc shells can benefit their mussel hosts. Endolithic infestation significantly reduced body temperatures of sun-exposed mussels and, during unusually extreme heat stress, parasitised individuals suffered lower mortality rates than non-parasitised hosts. This beneficial effect was related to the white discolouration caused by the excavation activity of endoliths. Under climate warming, species relationships may be drastically realigned and conditional benefits of phototrophic endolithic parasites may become more important than the costs of infestation.

  13. Enemies with benefits: parasitic endoliths protect mussels against heat stress

    PubMed Central

    Zardi, G. I.; Nicastro, K. R.; McQuaid, C. D.; Ng, T. P. T.; Lathlean, J.; Seuront, L.

    2016-01-01

    Positive and negative aspects of species interactions can be context dependant and strongly affected by environmental conditions. We tested the hypothesis that, during periods of intense heat stress, parasitic phototrophic endoliths that fatally degrade mollusc shells can benefit their mussel hosts. Endolithic infestation significantly reduced body temperatures of sun-exposed mussels and, during unusually extreme heat stress, parasitised individuals suffered lower mortality rates than non-parasitised hosts. This beneficial effect was related to the white discolouration caused by the excavation activity of endoliths. Under climate warming, species relationships may be drastically realigned and conditional benefits of phototrophic endolithic parasites may become more important than the costs of infestation. PMID:27506855

  14. Drivers of aggregation in a novel arboreal parasite: the influence of host size and infra-populations.

    PubMed

    Yule, Kirsty J; Burns, Kevin C

    2015-02-01

    As a novel arboreal parasite, New Zealand's largest endemic moth, Aenetus virescens, is a biological oddity. With arguably the most unusual lepidopteran life history on earth, larvae grow to 100mm, spending ∼6 years as wood-boring parasites feeding on host tree phloem. Parasite fitness is a product of host suitability. Parasite discrimination between heterogeneous hosts in fragmented populations shapes parasite aggregation. We investigated whether A. virescens aggregation among hosts occurs randomly (target area effect), or if larvae select hosts based on host quality (ideal free distribution). Using long-term larval growth as an indicator of energy intake, we examined A. virescens aggregation in relation to host size and infra-population. Using a generalised linear model, the relationship between parasite intensity and host tree size was analysed. Reduced major axis regression was used to evaluate A. virescens growth after 1 year. Linear mixed-effects models inferred the influence of parasite infra-population on parasite growth, with host tree as a random factor. Results indicate parasite intensity scaled positively with host size. Furthermore, parasite growth remained consistent throughout ontogeny regardless of host size or parasite infra-population. Aenetus virescens aggregation among hosts violates the ideal free distribution hypothesis, occurring instead as a result of host size, supporting the target area effect. Copyright © 2014 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

  15. How have fisheries affected parasite communities?

    USGS Publications Warehouse

    Wood, Chelsea L.; Lafferty, Kevin D.

    2015-01-01

    To understand how fisheries affect parasites, we conducted a meta-analysis of studies that contrasted parasite assemblages in fished and unfished areas. Parasite diversity was lower in hosts from fished areas. Larger hosts had a greater abundance of parasites, suggesting that fishing might reduce the abundance of parasites by selectively removing the largest, most heavily parasitized individuals. After controlling for size, the effect of fishing on parasite abundance varied according to whether the host was fished and the parasite's life cycle. Parasites of unfished hosts were more likely to increase in abundance in response to fishing than were parasites of fished hosts, possibly due to compensatory increases in the abundance of unfished hosts. While complex life cycle parasites tended to decline in abundance in response to fishing, directly transmitted parasites tended to increase. Among complex life cycle parasites, those with fished hosts tended to decline in abundance in response to fishing, while those with unfished hosts tended to increase. However, among directly transmitted parasites, responses did not differ between parasites with and without fished hosts. This work suggests that parasite assemblages are likely to change substantially in composition in increasingly fished ecosystems, and that parasite life history and fishing status of the host are important in predicting the response of individual parasite species or groups to fishing.

  16. Parasites in algae mass culture.

    PubMed

    Carney, Laura T; Lane, Todd W

    2014-01-01

    Parasites are now known to be ubiquitous across biological systems and can play an important role in modulating algal populations. However, there is a lack of extensive information on their role in artificial ecosystems such as algal production ponds and photobioreactors. Parasites have been implicated in the demise of algal blooms. Because individual mass culture systems often tend to be unialgal and a select few algal species are in wide scale application, there is an increased potential for parasites to have a devastating effect on commercial scale monoculture. As commercial algal production continues to expand with a widening variety of applications, including biofuel, food and pharmaceuticals, the parasites associated with algae will become of greater interest and potential economic impact. A number of important algal parasites have been identified in algal mass culture systems in the last few years and this number is sure to grow as the number of commercial algae ventures increases. Here, we review the research that has identified and characterized parasites infecting mass cultivated algae, the techniques being proposed and or developed to control them, and the potential impact of parasites on the future of the algal biomass industry.

  17. Parasites in algae mass culture

    PubMed Central

    Carney, Laura T.; Lane, Todd W.

    2014-01-01

    Parasites are now known to be ubiquitous across biological systems and can play an important role in modulating algal populations. However, there is a lack of extensive information on their role in artificial ecosystems such as algal production ponds and photobioreactors. Parasites have been implicated in the demise of algal blooms. Because individual mass culture systems often tend to be unialgal and a select few algal species are in wide scale application, there is an increased potential for parasites to have a devastating effect on commercial scale monoculture. As commercial algal production continues to expand with a widening variety of applications, including biofuel, food and pharmaceuticals, the parasites associated with algae will become of greater interest and potential economic impact. A number of important algal parasites have been identified in algal mass culture systems in the last few years and this number is sure to grow as the number of commercial algae ventures increases. Here, we review the research that has identified and characterized parasites infecting mass cultivated algae, the techniques being proposed and or developed to control them, and the potential impact of parasites on the future of the algal biomass industry. PMID:24936200

  18. Malaria parasite development in mosquitoes.

    PubMed

    Beier, J C

    1998-01-01

    Mosquitoes of the genus Anopheles transmit malaria parasites to humans. Anopheles mosquito species vary in their vector potential because of environmental conditions and factors affecting their abundance, blood-feeding behavior, survival, and ability to support malaria parasite development. In the complex life cycle of the parasite in female mosquitoes, a process termed sporogony, mosquitoes acquire gametocyte-stage parasites from blood-feeding on an infected host. The parasites carry out fertilization in the midgut, transform to ookinetes, then oocysts, which produce sporozoites. Sporozoites invade the salivary glands and are transmitted when the mosquito feeds on another host. Most individual mosquitoes that ingest gametocytes do not support development to the sporozoite stage. Bottle-necks occur at every stage of the cycle in the mosquito. Powerful new techniques and approaches exist for evaluating malaria parasite development and for identifying mechanisms regulating malaria parasite-vector interactions. This review focuses on those interactions that are important for the development of new approaches for evaluating and blocking transmission in nature.

  19. Cardiac Involvement with Parasitic Infections

    PubMed Central

    Hidron, Alicia; Vogenthaler, Nicholas; Santos-Preciado, José I.; Rodriguez-Morales, Alfonso J.; Franco-Paredes, Carlos; Rassi, Anis

    2010-01-01

    Summary: Parasitic infections previously seen only in developing tropical settings can be currently diagnosed worldwide due to travel and population migration. Some parasites may directly or indirectly affect various anatomical structures of the heart, with infections manifested as myocarditis, pericarditis, pancarditis, or pulmonary hypertension. Thus, it has become quite relevant for clinicians in developed settings to consider parasitic infections in the differential diagnosis of myocardial and pericardial disease anywhere around the globe. Chagas' disease is by far the most important parasitic infection of the heart and one that it is currently considered a global parasitic infection due to the growing migration of populations from areas where these infections are highly endemic to settings where they are not endemic. Current advances in the treatment of African trypanosomiasis offer hope to prevent not only the neurological complications but also the frequently identified cardiac manifestations of this life-threatening parasitic infection. The lack of effective vaccines, optimal chemoprophylaxis, or evidence-based pharmacological therapies to control many of the parasitic diseases of the heart, in particular Chagas' disease, makes this disease one of the most important public health challenges of our time. PMID:20375355

  20. Evolutionary Origins of Rhizarian Parasites.

    PubMed

    Sierra, Roberto; Cañas-Duarte, Silvia J; Burki, Fabien; Schwelm, Arne; Fogelqvist, Johan; Dixelius, Christina; González-García, Laura N; Gile, Gillian H; Slamovits, Claudio H; Klopp, Christophe; Restrepo, Silvia; Arzul, Isabelle; Pawlowski, Jan

    2016-04-01

    The SAR group (Stramenopila, Alveolata, Rhizaria) is one of the largest clades in the tree of eukaryotes and includes a great number of parasitic lineages. Rhizarian parasites are obligate and have devastating effects on commercially important plants and animals but despite this fact, our knowledge of their biology and evolution is limited. Here, we present rhizarian transcriptomes from all major parasitic lineages in order to elucidate their evolutionary relationships using a phylogenomic approach. Our results suggest that Ascetosporea, parasites of marine invertebrates, are sister to the novel clade Apofilosa. The phytomyxean plant parasites branch sister to the vampyrellid algal ectoparasites in the novel clade Phytorhiza. They also show that Ascetosporea + Apofilosa + Retaria + Filosa + Phytorhiza form a monophyletic clade, although the branching pattern within this clade is difficult to resolve and appears to be model-dependent. Our study does not support the monophyly of the rhizarian parasitic lineages (Endomyxa), suggesting independent origins for rhizarian animal and plant parasites. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. Congenital parasitic infections: a review.

    PubMed

    Carlier, Yves; Truyens, Carine; Deloron, Philippe; Peyron, François

    2012-02-01

    This review defines the concepts of maternal-fetal (congenital) and vertical transmissions (mother-to-child) of pathogens and specifies the human parasites susceptible to be congenitally transferred. It highlights the epidemiological features of this transmission mode for the three main congenital parasitic infections due to Toxoplasma gondii, Trypanosoma cruzi and Plasmodium sp. Information on the possible maternal-fetal routes of transmission, the placental responses to infection and timing of parasite transmission are synthesized and compared. The factors susceptible to be involved in parasite transmission and development of congenital parasitic diseases, such as the parasite genotypes, the maternal co-infections and parasitic load, the immunological features of pregnant women and the capacity of some fetuses/neonates to overcome their immunological immaturity to mount an immune response against the transmitted parasites are also discussed and compared. Analysis of clinical data indicates that parasitic congenital infections are often asymptomatic, whereas symptomatic newborns generally display non-specific symptoms. The long-term consequences of congenital infections are also mentioned, such as the imprinting of neonatal immune system and the possible trans-generational transmission. The detection of infection in pregnant women is mainly based on standard serological or parasitological investigations. Amniocentesis and cordocentesis can be used for the detection of some fetal infections. The neonatal infection can be assessed using parasitological, molecular or immunological methods; the place of PCR in such neonatal diagnosis is discussed. When such laboratory diagnosis is not possible at birth or in the first weeks of life, standard serological investigations can also be performed 8-10 months after birth, to avoid detection of maternal transmitted antibodies. The specific aspects of treatment of T. gondii, T. cruzi and Plasmodium congenital infections are

  2. Predictability of helminth parasite host range using information on geography, host traits and parasite community structure.

    PubMed

    Dallas, Tad; Park, Andrew W; Drake, John M

    2017-02-01

    Host-parasite associations are complex interactions dependent on aspects of hosts (e.g. traits, phylogeny or coevolutionary history), parasites (e.g. traits and parasite interactions) and geography (e.g. latitude). Predicting the permissive host set or the subset of the host community that a parasite can infect is a central goal of parasite ecology. Here we develop models that accurately predict the permissive host set of 562 helminth parasites in five different parasite taxonomic groups. We developed predictive models using host traits, host taxonomy, geographic covariates, and parasite community composition, finding that models trained on parasite community variables were more accurate than any other covariate group, even though parasite community covariates only captured a quarter of the variance in parasite community composition. This suggests that it is possible to predict the permissive host set for a given parasite, and that parasite community structure is an important predictor, potentially because parasite communities are interacting non-random assemblages.

  3. Spread of an introduced parasite across the Hawaiian archipelago independent of its introduced host

    DOE PAGES

    Gagne, Roderick B.; Hogan, J. Derek; McIntyre, Peter B.; ...

    2014-11-11

    1. Co-introductions of non-native parasites with non-native hosts can be a major driver of disease emergence in native species, but the conditions that promote the establishment and spread of nonnative parasites remain poorly understood. Here, we characterise the infection of a native host species by a non-native parasite relative to the distribution and density of the original non-native host species and a suite of organismal and environmental factors that have been associated with parasitism, but not commonly considered within a single system. 2. We examined the native Hawaiian goby Awaous stamineus across 23 catchments on five islands for infection bymore » the non-native nematode parasite Camallanus cotti. We used model selection to test whether parasite infection was associated with the genetic diversity, size and population density of native hosts, the distribution and density of non-native hosts, land use and water quality. 3. We found that the distribution of non-native C. cotti parasites has become decoupled from the non-native hosts that were primary vectors of introduction to the Hawaiian Islands. Although no single intrinsic or extrinsic factor was identified that best explains parasitism of A. stamineus by C. cotti, native host size, population density and water quality were consistently identified as influencing parasite intensity and prevalence. 4. The introduction of non-native species can indirectly influence native species through infection of co-introduced parasites. Here, we show that the effects of enemy addition can extend beyond the range of non-native hosts through the independent spread of non-native parasites. This suggests that control of non-native hosts is not sufficient to halt the spread of introduced parasites. Furthermore, designing importation regulations to prevent host parasite co-introductions can promote native species conservation, even in remote areas that may not seem susceptible to human influence.« less

  4. Glomerulopathy Associated with Parasitic Infections

    PubMed Central

    van Velthuysen, M.-L. F.; Florquin, S.

    2000-01-01

    Although parasitic infections do not usually present with disturbance in renal function, glomerular lesions can be seen in most of these infections. The glomerular lesions observed in parasitic infections cover the whole range of glomerular lesions known, but most of them are proliferative. Little is known of the exact pathogenic mechanisms. In this review, we try to explain the glomerular lesions associated with parasitic infections in terms of the specific immunologic events observed during these diseases against the background of recent developments in the general knowledge of the pathogenesis of glomerular disease. PMID:10627491

  5. Parasites as probes for biodiversity.

    PubMed

    Gardner, S L; Campbell, M L

    1992-08-01

    Cestodes of the genus Linstowia, parasitic in marsupials, show patterns of coevolution and ancient historical-ecological connections. Correlated with the breakup of the austral landmasses (Gondwanaland) of the Neotropical and Australian regions from the Antarctic continent, the age of this host-parasite community is estimated to be between 60 and 70 million years old. Based on the data from the survey of parasites of mammals from throughout Bolivia and from the phylogenetic analysis of the cestodes, we urge the planners of biodiversity preserves in the neotropics to consider the Yungas of Bolivia as a region that supports an ancient ecological community worthy of consideration as a biopreserve.

  6. Intestinal parasites of raccoons (Procyon lotor) from southwest British Columbia.

    PubMed Central

    Ching, H L; Leighton, B J; Stephen, C

    2000-01-01

    This is the first extensive survey of metazoan parasites (particularly of the roundworm Baylisascaris procyonis) from the intestines of raccoons in British Columbia. The sample collected in 1997-1998 consisted of 82 raccoons that had been sick or had been killed accidentally by automobiles. Fifteen parasite taxa were found: 3 nematodes, 9 digenetic trematodes, 2 acanthocephalans and 1 cestode. Ten of these parasites constitute new host records for raccoons, including 4 digenetic trematodes that have been reported in marine birds and mammals on the Pacific Coast of North America. Baylisascaris procyonis infected 61% of the raccoons with a mean intensity of 27. The high rate of infection indicates a large potential for environmental contamination and, thus, human and animal exposure to infectious eggs. Prevention of larva migrans is discussed, particularly for people in contact with raccoons in wildlife rehabilitation centers. PMID:10805249

  7. Why join groups? Lessons from parasite-manipulated Artemia.

    PubMed

    Rode, Nicolas O; Lievens, Eva J P; Flaven, Elodie; Segard, Adeline; Jabbour-Zahab, Roula; Sanchez, Marta I; Lenormand, Thomas

    2013-04-01

    Grouping behaviours (e.g. schooling, shoaling and swarming) are commonly explicated through adaptive hypotheses such as protection against predation, access to mates or improved foraging. However, the hypothesis that aggregation can result from manipulation by parasites to increase their transmission has never been demonstrated. We investigated this hypothesis using natural populations of two crustacean hosts (Artemia franciscana and Artemia parthenogenetica) infected with one cestode and two microsporidian parasites. We found that swarming propensity increased in cestode-infected hosts and that red colour intensity was higher in swarming compared with non-swarming infected hosts. These effects likely result in increased cestode transmission to its final avian host. Furthermore, we found that microsporidian-infected hosts had both increased swarming propensity and surfacing behaviour. Finally, we demonstrated using experimental infections that these concurrent manipulations result in increased spore transmission to new hosts. Hence, this study suggests that parasites can play a prominent role in host grouping behaviours.

  8. Parasites in pet reptiles

    PubMed Central

    2011-01-01

    Exotic reptiles originating from the wild can be carriers of many different pathogens and some of them can infect humans. Reptiles imported into Slovenia from 2000 to 2005, specimens of native species taken from the wild and captive bred species were investigated. A total of 949 reptiles (55 snakes, 331 lizards and 563 turtles), belonging to 68 different species, were examined for the presence of endoparasites and ectoparasites. Twelve different groups (Nematoda (5), Trematoda (1), Acanthocephala (1), Pentastomida (1) and Protozoa (4)) of endoparasites were determined in 26 (47.3%) of 55 examined snakes. In snakes two different species of ectoparasites were also found. Among the tested lizards eighteen different groups (Nematoda (8), Cestoda (1), Trematoda (1), Acanthocephala (1), Pentastomida (1) and Protozoa (6)) of endoparasites in 252 (76.1%) of 331 examined animals were found. One Trombiculid ectoparasite was determined. In 563 of examined turtles eight different groups (Nematoda (4), Cestoda (1), Trematoda (1) and Protozoa (2)) of endoparasites were determined in 498 (88.5%) animals. In examined turtles three different species of ectoparasites were seen. The established prevalence of various parasites in reptiles used as pet animals indicates the need for examination on specific pathogens prior to introduction to owners. PMID:21624124

  9. Synanthropic birds and parasites.

    PubMed

    Dipineto, Ludovico; Borrelli, Luca; Pepe, Paola; Fioretti, Alessandro; Caputo, Vincenzo; Cringoli, Giuseppe; Rinaldi, Laura

    2013-12-01

    This paper describes the parasitologic findings for 60 synanthropic bird carcasses recovered in the Campania region of southern Italy. Birds consisted of 20 yellow-legged gulls (Larus michahellis), 15 rock pigeons (Columba livia), 15 common kestrels (Falco tinnunculus), and 10 carrion crows (Corvus corone). Each carcass was examined to detect the presence of ectoparasites and then necropsied to detect helminths. Ectoparasites occurred in 100% of the birds examined. In particular, chewing lice were recovered with a prevalence of 100%, whereas Pseudolynchia canariensis (Hippoboscidae) were found only in pigeons with a prevalence of 80%. Regarding endoparasites, a total of seven helminth species were identified: three nematodes (Ascaridia columbae, Capillaria columbae, Physaloptera alata), one cestoda (Raillietina tetragona), one trematoda (Cardiocephalus longicollis), and two acanthocephalans (Centrorhynchus globocaudatus and Centrorhynchus buteonis). The findings of the present study add data to the parasitologic scenario of synanthropic birds. This is important because parasitic infection can lead to serious health problems when combined with other factors and may affect flying performance and predatory effectiveness.

  10. Parasites in pet reptiles.

    PubMed

    Rataj, Aleksandra Vergles; Lindtner-Knific, Renata; Vlahović, Ksenija; Mavri, Urška; Dovč, Alenka

    2011-05-30

    Exotic reptiles originating from the wild can be carriers of many different pathogens and some of them can infect humans. Reptiles imported into Slovenia from 2000 to 2005, specimens of native species taken from the wild and captive bred species were investigated. A total of 949 reptiles (55 snakes, 331 lizards and 563 turtles), belonging to 68 different species, were examined for the presence of endoparasites and ectoparasites. Twelve different groups (Nematoda (5), Trematoda (1), Acanthocephala (1), Pentastomida (1) and Protozoa (4)) of endoparasites were determined in 26 (47.3%) of 55 examined snakes. In snakes two different species of ectoparasites were also found. Among the tested lizards eighteen different groups (Nematoda (8), Cestoda (1), Trematoda (1), Acanthocephala (1), Pentastomida (1) and Protozoa (6)) of endoparasites in 252 (76.1%) of 331 examined animals were found. One Trombiculid ectoparasite was determined. In 563 of examined turtles eight different groups (Nematoda (4), Cestoda (1), Trematoda (1) and Protozoa (2)) of endoparasites were determined in 498 (88.5%) animals. In examined turtles three different species of ectoparasites were seen. The established prevalence of various parasites in reptiles used as pet animals indicates the need for examination on specific pathogens prior to introduction to owners.

  11. Myxozoan parasitism in waterfowl.

    PubMed

    Bartholomew, Jerri L; Atkinson, Stephen D; Hallett, Sascha L; Lowenstine, Linda J; Garner, Michael M; Gardiner, Chris H; Rideout, Bruce A; Keel, M Kevin; Brown, Justin D

    2008-08-01

    Myxozoans are spore-forming, metazoan parasites common in cold-blooded aquatic vertebrates, especially fishes, with alternate life cycle stages developing in invertebrates. We report nine cases of infection in free-flying native and captive exotic ducks (Anseriformes: Anatidae) from locations across the United States and describe the first myxozoan in birds, Myxidium anatidum n. sp. We found developmental stages and mature spores in the bile ducts of a Pekin duck (domesticated Anas platyrhynchos). Spores are lens-shaped in sutural view, slightly sigmoidal in valvular view, with two polar capsules, and each valve cell has 14-16 longitudinal surface ridges. Spore dimensions are 23.1 microm x 10.8 microm x 11.2 microm. Phylogenetic analysis of the ssrRNA gene revealed closest affinity with Myxidium species described from chelonids (tortoises). Our novel finding broadens the definition of the Myxozoa to include birds as hosts and has implications for understanding myxozoan evolution, and mechanisms of geographical and host range extension. The number of infection records indicates this is not an incidental occurrence, and the detection of such widely dispersed cases suggests more myxozoans in birds will be encountered with increased surveillance of these hosts for pathogens.

  12. Longitudinal study of parasite-induced mortality of a long-lived host: the importance of exposure to non-parasitic stressors.

    PubMed

    Chin, Hilary M-H; Luong, Lien T; Shostak, Allen W

    2017-07-11

    Hosts face mortality from parasitic and environmental stressors, but interactions of parasitism with other stressors are not well understood, particularly for long-lived hosts. We monitored survival of flour beetles (Tribolium confusum) in a longitudinal design incorporating cestode (Hymenolepis diminuta) infection, starvation and exposure to the pesticide diatomaceous earth (DE). We found that cestode cysticercoids exhibit increasing morphological damage and decreasing ability to excyst over time, but were never eliminated from the host. In the presence of even mild environmental stressors, host lifespan was reduced sufficiently that extensive degradation of cysticercoids was never realized. Median host lifespan was 200 days in the absence of stressors, and 3-197 days with parasitism, starvation and/or DE. Early survival of parasitized hosts was higher relative to controls in the presence of intermediate concentrations of DE, but reduced under all other conditions tested. Parasitism increased host mortality in the presence of other stressors at times when parasitism alone did not cause mortality, consistent with an interpretation of synergy. Environmental stressors modified the parasite numbers needed to reveal intensity-dependent host mortality, but only rarely masked intensity dependence. The longitudinal approach produced observations that would have been overlooked or misinterpreted if survival had only been monitored at a single time point.

  13. Immunodominance: a new hypothesis to explain parasite escape and host/parasite equilibrium leading to the chronic phase of Chagas' disease?

    PubMed

    Rodrigues, M M; Alencar, B C G de; Claser, C; Tzelepis, F

    2009-03-01

    Intense immune responses are observed during human or experimental infection with the digenetic protozoan parasite Trypanosoma cruzi. The reasons why such immune responses are unable to completely eliminate the parasites are unknown. The survival of the parasite leads to a parasite-host equilibrium found during the chronic phase of chagasic infection in most individuals. Parasite persistence is recognized as the most likely cause of the chagasic chronic pathologies. Therefore, a key question in Chagas' disease is to understand how this equilibrium is established and maintained for a long period. Understanding the basis for this equilibrium may lead to new approaches to interventions that could help millions of individuals at risk for infection or who are already infected with T. cruzi. Here, we propose that the phenomenon of immunodominance may be significant in terms of regulating the host-parasite equilibrium observed in Chagas' disease. T. cruzi infection restricts the repertoire of specific T cells generating, in some cases, an intense immunodominant phenotype and in others causing a dramatic interference in the response to distinct epitopes. This immune response is sufficiently strong to maintain the host alive during the acute phase carrying them to the chronic phase where transmission usually occurs. At the same time, immunodominance interferes with the development of a higher and broader immune response that could be able to completely eliminate the parasite. Based on this, we discuss how we can interfere with or take advantage of immunodominance in order to provide an immunotherapeutic alternative for chagasic individuals.

  14. Host social organization and mating system shape parasite transmission opportunities in three European bat species.

    PubMed

    van Schaik, J; Kerth, G

    2017-02-01

    For non-mobile parasites living on social hosts, infection dynamics are strongly influenced by host life history and social system. We explore the impact of host social systems on parasite population dynamics by comparing the infection intensity and transmission opportunities of three mite species of the genus Spinturnix across their three European bat hosts (Myotis daubentonii, Myotis myotis, Myotis nattereri) during the bats' autumn mating season. Mites mainly reproduce in host maternity colonies in summer, but as these colonies are closed, opportunities for inter-colony transmission are limited to host interactions during the autumn mating season. The three investigated hosts differ considerably in their social system, most notably in maternity colony size, mating system, and degree of male summer aggregation. We observed marked differences in parasite infection during the autumn mating period between the species, closely mirroring the predictions made based on the social systems of the hosts. Increased host aggregation sizes in summer yielded higher overall parasite prevalence and intensity, both in male and female hosts. Moreover, parasite levels in male hosts differentially increased throughout the autumn mating season in concordance with the degree of contact with female hosts afforded by the different mating systems of the hosts. Critically, the observed host-specific differences have important consequences for parasite population structure and will thus affect the coevolutionary dynamics between the interacting species. Therefore, in order to accurately characterize host-parasite dynamics in hosts with complex social systems, a holistic approach that investigates parasite infection and transmission across all periods is warranted.

  15. [Effects of Cuscuta australis parasitism on the growth, reproduction and defense of Solidago canadensis].

    PubMed

    Yang, Bei-fen; Du, Le-shan; Li, Jun-min

    2015-11-01

    In order to find out how parasitic Cuscuta australis influences the growth and reproduction of Solidago canadensis, the effects of the parasitism of C. australis on the morphological, growth and reproductive traits of S. canadensis were examined and the relationships between the biomass and the contents of the secondary metabolites were analyzed. The results showed that the parasitism significantly reduced the plant height, basal diameter, root length, root diameter, root biomass, stem biomass, leaf biomass, total biomass, number of inflorescences branches, axis length of inflorescence, and number of inflorescence. In particular, plant height, number of inflorescence and the stem biomass of parasitized S. canadensis were only 1/2, 1/5 and 1/8 of non-parasitized plants, respectively. There was no significant difference of plant height, root length, stem biomass and total biomass between plants parasitized with high and low intensities. But the basal diameter, root volume, leaf biomass, root biomass, the number of inflorescences branches, axis length of inflorescence and number of inflorescence of S. canadensis parasitized with high intensity were significantly lower than those of plants parasitized with low intensity. The parasitism of C. australis significantly increased the tannins content in the root and the flavonoids content in the stem of S. canadensis. The biomass of S. canadensis was significantly negatively correlated with the tannin content in the root and the flavonoids content in the stem. These results indicated that the parasitism of C. australis could inhibit the growth of S. canadensis by changing the resources allocation patterns as well as reducing the resources obtained by S. canadensis.

  16. Pregnancy, nutrition and parasitic diseases.

    PubMed

    Steketee, Richard W

    2003-05-01

    In the developing world, young women, pregnant women, and their infants and children frequently experience a cycle where undernutrition (macronutrient and micronutrient) and repeated infection, including parasitic infections, lead to adverse consequences that can continue from one generation to the next. Among parasitic infections, malaria and intestinal helminths coexist widely with micronutrient deficiencies and contribute importantly to anemia and this cycle of retarded growth and development. In somewhat more limited or focal geographic settings, other parasitic diseases (e.g., schistosomiasis, filariasis) contribute similarly to this cycle. It is undoubtedly much better to enter a pregnancy free of infection and nutritionally replete than the various alternatives. Existing intervention strategies for micronutrient support and for the control of common parasitic infections before or during pregnancy, particularly malaria and intestinal helminths, should be followed. However, further research to identify barriers and priority approaches to achieving this goal remain very important in resource-poor settings where targeted public health efforts are required.

  17. Tropical parasitic diseases and women.

    PubMed

    Okwa, O O

    2007-12-01

    Tropical parasitic diseases constitute the greatest threat to the health and socio-economic status of women as a gender and social group. There are some gender specific ways in which parasitic diseases affect women in contrast to men due to differences in exposure, occupational risk, sociocultural behavior, gender roles and practices. These parasitic diseases confer some social stigma, which affects the health seeking behavior of women. Women are therefore important in the control of these parasitic diseases and they are key agents of change, if they are included in community control programs. Women need more attention in endemic areas as a group that had been neglected. This deprived and excluded group have got vital role to play, as discussed in this review.

  18. Atypical parasitic ischiopagus conjoined twins.

    PubMed

    Corona-Rivera, J Román; Corona-Rivera, Enrique; Franco-Topete, Ramón; Acosta-León, Jorge; Aguila-Dueñas, Virginia; Corona-Rivera, Alfredo

    2003-02-01

    Occurrence of asymmetrical or parasitic conjoined twins (CT) is rare, and currently they are classified analogically to the common unions of symmetrical CT. The authors report on an infant with a parasitic third limb attached to the left lateral aspect of the autosite trunk, in whom male gonadal tissue was found histologically. Parasite parts included complete left lower limb, hemipelvis, lumbosacral vertebral column, spinal cord, and one kidney with ureter and adrenal gland. Autosite anomalies comprised a small left diaphragmatic defect, omphalocele, exstrophy of cloaca, and lumbar meningomyelocele. The authors considered this case to be a rare atypical parasitic ischiopagus CT. The differential diagnosis of the type of twining and other entities with caudal duplications is analyzed briefly.

  19. Meso- and bathy-pelagic fish parasites at the Mid-Atlantic Ridge (MAR): Low host specificity and restricted parasite diversity

    NASA Astrophysics Data System (ADS)

    Klimpel, Sven; Busch, Markus Wilhelm; Sutton, Tracey; Palm, Harry Wilhelm

    2010-04-01

    Seven meso- and bathy-pelagic fish species from the Mid-Atlantic Ridge (MAR) were firstly studied for fish parasites and feeding ecology. With a total of seven parasite species, the 247 meso- and bathy-pelagic deep-sea fish specimens belonging to the families Melamphaidae (3 spp.), Myctophidae (3 spp.) and Stomiidae (1 sp.) revealed low parasite diversity. The genetically identified nematodes Anisakis simplex (s.s.) and Anisakis pegreffii from the body cavity, liver and muscles of Myctophum punctatum were the most abundant parasites, reaching a prevalence of 91.4% and mean intensity of 3.1 (1-14). Anisakis sp. (unidentified) infected Chauliodus sloani and Poromitra crassiceps. Bothriocephalidean and tetraphyllidean cestode larvae infected Benthosema glaciale, the latter also occurring in C. sloani and Scopelogadus beanii, at low prevalences. Adult parasites at low infection rates included the digenean Lethadena sp. (2.9%), and the two copepod species Sarcotretes scopeli (5.7%) and Tautochondria dolichoura (5.3-11.4%). The myctophid Lampanyctus macdonaldi and the melamphaid Scopelogadus mizolepis mizolepis were free of parasites. Analyses of the stomach contents revealed crustaceans, especially copepods and euphausiids for the myctophids and also amphipods for the melamphaids as predominant prey items. While all stomachs showing distinct content comprising often unidentified 'tissue' (possibly gelatinous zooplankton), only C. sloani preyed upon fish. Though this feeding habit would enable transfer of a variety of crustacean-transmitted parasites into the fish, the parasite fauna in the meso- and bathy-pelagic fish was species poor. All observed parasites showed low host specificity, demonstrating no distinct pattern of host-parasite co-evolution. The MAR is no barrier for the parasite distribution in the North Atlantic meso- and bathy-pelagial.

  20. Molecular diagnostics and parasitic disease.

    PubMed

    Vasoo, Shawn; Pritt, Bobbi S

    2013-09-01

    Molecular parasitology represents an emerging field in microbiology diagnostics. Although most assays use nonstandardized, laboratory-developed methods, a few commercial systems have recently become available and are slowly being introduced into larger laboratories. In addition, a few methodologies show promise for use in field settings in which parasitic infections are endemic. This article reviews the available techniques and their applications to major parasitic diseases such as malaria, leishmaniasis, and trichomoniasis.

  1. [Water and intestinal parasitic diseases].

    PubMed

    Romanenko, N A; Belova, E G; Baburina, L V; Novosil'tsev, G I; Chernyshenko, A I

    2004-01-01

    The paper presents data on the rates of Lamblia cyst dissemination of surface water sources in foreign countries, the Russian Federation, Moscow, and the Moscow Region. It shows a role of drinking water in the spread of intestinal parasitic diseases. In accordance with parasitological parameters, specific data on improvement of methodological control of water quality are presented. The dosages of ultraviolet radiation are given in relation to water decontamination of parasitic disease germs.

  2. Microsatellite analysis of malaria parasites.

    PubMed

    Orjuela-Sánchez, Pamela; Brandi, Michelle C; Ferreira, Marcelo U

    2013-01-01

    Microsatellites have been increasingly used to investigate the population structure of malaria parasites, to map genetic loci contributing to phenotypes such as drug resistance and virulence in laboratory crosses and genome-wide association studies and to distinguish between treatment failures and new infections in clinical trials. Here, we provide optimized protocols for genotyping highly polymorphic microsatellites sampled from across the genomes of the human malaria parasites Plasmodium falciparum and P. vivax that have been extensively used in research laboratories worldwide.

  3. Parasites and altruism: converging roads.

    PubMed

    Zuk, Marlene; Borrello, Mark E

    2013-01-01

    W.D. Hamilton was most known for his work on two topics: social evolution and parasites. Although at first glance these seem to be disparate interests, they share many attributes and have logical connections within evolutionary biology. Nevertheless, Hamilton's contributions in these areas met with very different receptions, with his place in the field of social evolution assured, but his work on the role of parasites perceived as more specialized. We take an historical approach to examine the reasons for this difference.

  4. Parasitic Effects on Memristor Dynamics

    NASA Astrophysics Data System (ADS)

    Itoh, Makoto; Chua, Leon O.

    2016-06-01

    In this paper, we show that parasitic elements have a significant effect on the dynamics of memristor circuits. We first show that certain 2-terminal elements such as memristors, memcapacitors, and meminductors can be used as nonvolatile memories, if the principle of conservation of state variables hold by open-circuiting, or short-circuiting, their terminals. We also show that a passive memristor with a strictly-increasing constitutive relation will eventually lose its stored flux when we switch off the power if there is a parasitic capacitance across the memristor. Similarly, a memcapacitor (resp., meminductor) with a positive memcapacitance (resp., meminductance) will eventually lose their stored physical states when we switch off the power, if it is connected to a parasitic resistance. We then show that the discontinuous jump that circuit engineers assumed to occur at impasse points of memristor circuits contradicts the principles of conservation of charge and flux at the time of the discontinuous jump. A parasitic element can be used to break an impasse point, resulting in the emergence of a continuous oscillation in the circuit. We also define a distance, a diameter, and a dimension, for each circuit element in order to measure the complexity order of the parasitic elements. They can be used to find higher-order parasitic elements which can break impasse points. Furthermore, we derived a memristor-based Chua’s circuit from a three-element circuit containing a memristor by connecting two parasitic memcapacitances to break the impasse points. We finally show that a higher-order parasitic element can be used for breaking the impasse points on two-dimensional and three-dimensional constrained spaces.

  5. Pervasiveness of Parasites in Pollinators

    PubMed Central

    Evison, Sophie E. F.; Roberts, Katherine E.; Laurenson, Lynn; Pietravalle, Stéphane; Hui, Jeffrey; Biesmeijer, Jacobus C.; Smith, Judith E.; Budge, Giles; Hughes, William O. H.

    2012-01-01

    Many pollinator populations are declining, with large economic and ecological implications. Parasites are known to be an important factor in the some of the population declines of honey bees and bumblebees, but little is known about the parasites afflicting most other pollinators, or the extent of interspecific transmission or vectoring of parasites. Here we carry out a preliminary screening of pollinators (honey bees, five species of bumblebee, three species of wasp, four species of hoverfly and three genera of other bees) in the UK for parasites. We used molecular methods to screen for six honey bee viruses, Ascosphaera fungi, Microsporidia, and Wolbachia intracellular bacteria. We aimed simply to detect the presence of the parasites, encompassing vectoring as well as actual infections. Many pollinators of all types were positive for Ascosphaera fungi, while Microsporidia were rarer, being most frequently found in bumblebees. We also detected that most pollinators were positive for Wolbachia, most probably indicating infection with this intracellular symbiont, and raising the possibility that it may be an important factor in influencing host sex ratios or fitness in a diversity of pollinators. Importantly, we found that about a third of bumblebees (Bombus pascuorum and Bombus terrestris) and a third of wasps (Vespula vulgaris), as well as all honey bees, were positive for deformed wing virus, but that this virus was not present in other pollinators. Deformed wing virus therefore does not appear to be a general parasite of pollinators, but does interact significantly with at least three species of bumblebee and wasp. Further work is needed to establish the identity of some of the parasites, their spatiotemporal variation, and whether they are infecting the various pollinator species or being vectored. However, these results provide a first insight into the diversity, and potential exchange, of parasites in pollinator communities. PMID:22347356

  6. Pervasiveness of parasites in pollinators.

    PubMed

    Evison, Sophie E F; Roberts, Katherine E; Laurenson, Lynn; Pietravalle, Stéphane; Hui, Jeffrey; Biesmeijer, Jacobus C; Smith, Judith E; Budge, Giles; Hughes, William O H

    2012-01-01

    Many pollinator populations are declining, with large economic and ecological implications. Parasites are known to be an important factor in the some of the population declines of honey bees and bumblebees, but little is known about the parasites afflicting most other pollinators, or the extent of interspecific transmission or vectoring of parasites. Here we carry out a preliminary screening of pollinators (honey bees, five species of bumblebee, three species of wasp, four species of hoverfly and three genera of other bees) in the UK for parasites. We used molecular methods to screen for six honey bee viruses, Ascosphaera fungi, Microsporidia, and Wolbachia intracellular bacteria. We aimed simply to detect the presence of the parasites, encompassing vectoring as well as actual infections. Many pollinators of all types were positive for Ascosphaera fungi, while Microsporidia were rarer, being most frequently found in bumblebees. We also detected that most pollinators were positive for Wolbachia, most probably indicating infection with this intracellular symbiont, and raising the possibility that it may be an important factor in influencing host sex ratios or fitness in a diversity of pollinators. Importantly, we found that about a third of bumblebees (Bombus pascuorum and Bombus terrestris) and a third of wasps (Vespula vulgaris), as well as all honey bees, were positive for deformed wing virus, but that this virus was not present in other pollinators. Deformed wing virus therefore does not appear to be a general parasite of pollinators, but does interact significantly with at least three species of bumblebee and wasp. Further work is needed to establish the identity of some of the parasites, their spatiotemporal variation, and whether they are infecting the various pollinator species or being vectored. However, these results provide a first insight into the diversity, and potential exchange, of parasites in pollinator communities.

  7. Evolution: Causality and the Origin of Parasitism.

    PubMed

    Janouskovec, Jan; Keeling, Patrick J

    2016-02-22

    The first comparison of parasitic trypanosomatids to their free-living relatives reveals that some characteristics once linked to parasitism actually predate it. Parallel comparisons of other parasites suggest we need to rethink the drivers and consequences of the parasitic lifestyle.

  8. A lack of crowding? Body size does not decrease with density for two behavior-manipulating parasites.

    PubMed

    Weinersmith, Kelly L; Warinner, Chloe B; Tan, Virginia; Harris, David J; Mora, Adrienne B; Kuris, Armand M; Lafferty, Kevin D; Hechinger, Ryan F

    2014-07-01

    For trophically transmitted parasites that manipulate the phenotype of their hosts, whether the parasites do or do not experience resource competition depends on such factors as the size of the parasites relative to their hosts, the intensity of infection, the extent to which parasites share the cost of defending against the host's immune system or manipulating their host, and the extent to which parasites share transmission goals. Despite theoretical expectations for situations in which either no, or positive, or negative density-dependence should be observed, most studies document only negative density-dependence for trophically transmitted parasites. However, this trend may be an artifact of most studies having focused on systems in which parasites are large relative to their hosts. Yet, systems are common where parasites are small relative to their hosts, and these trophically transmitted parasites may be less likely to experience resource limitation. We looked for signs of density-dependence in Euhaplorchis californiensis (EUHA) and Renicola buchanani (RENB), two manipulative trematode parasites infecting wild-caught California killifish (Fundulus parvipinnis). These parasites are small relative to killifish (suggesting resources are not limiting), and are associated with changes in killifish behavior that are dependent on parasite-intensity and that increase predation rates by the parasites' shared final host (indicating the possibility for cost sharing). We did not observe negative density-dependence in either species, indicating that resources are not limiting. In fact, observed patterns indicate possible mild positive density-dependence for EUHA. Although experimental confirmation is required, our findings suggest that some behavior-manipulating parasites suffer no reduction in size, and may even benefit when "crowded" by conspecifics. © The Author 2014. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology

  9. Birds are islands for parasites.

    PubMed

    Koop, Jennifer A H; DeMatteo, Karen E; Parker, Patricia G; Whiteman, Noah K

    2014-08-01

    Understanding the mechanisms driving the extraordinary diversification of parasites is a major challenge in evolutionary biology. Co-speciation, one proposed mechanism that could contribute to this diversity is hypothesized to result from allopatric co-divergence of host-parasite populations. We found that island populations of the Galápagos hawk (Buteo galapagoensis) and a parasitic feather louse species (Degeeriella regalis) exhibit patterns of co-divergence across variable temporal and spatial scales. Hawks and lice showed nearly identical population genetic structure across the Galápagos Islands. Hawk population genetic structure is explained by isolation by distance among islands. Louse population structure is best explained by hawk population structure, rather than isolation by distance per se, suggesting that lice tightly track the recent population histories of their hosts. Among hawk individuals, louse populations were also highly structured, suggesting that hosts serve as islands for parasites from an evolutionary perspective. Altogether, we found that host and parasite populations may have responded in the same manner to geographical isolation across spatial scales. Allopatric co-divergence is likely one important mechanism driving the diversification of parasites.

  10. Lipids and the malarial parasite*

    PubMed Central

    Holz, George G.

    1977-01-01

    Merozoite endocytosis initiates Plasmodium development in a vacuole bounded by an erythrocyte-derived membrane, whose asymmetrical distribution of lipids and proteins is reversed in its orientation with respect to the parasite plasma membrane. Reorientation may accompany the proliferation of the membrane associated with the parasite's growth and phagocytic and pinocytic feeding. Increases in the membrane surface area of the parasite, and in some cases of the erythrocyte, parallel parasite growth and segmentation. Augmentation of all the membrane systems of the infected erythrocyte causes the lipid content to rise rapidly, but the parasite lipid composition differs from that of the erythrocyte in many respects: it is higher in diacyl phosphatidylethanolamine, phosphatidylinositol, polyglycerol phosphatides, diacylglycerols, unesterified fatty acids, triacylglycerols, and hexadecanoic and octadecenoic fatty acids and lower in sphingomyelin, phosphatidylserine, alkoxy phosphatidylethanolamine, cholesterol, and polyunsaturated fatty acids. Active lipid metabolism accompanies the membrane proliferation associated with feeding, growth, and reproduction. Plasmodium is incapable of de novo biosynthesis of fatty acids and cholesterol; however, it can fabricate its glycerides and phosphoglycerides with host-supplied fatty acids, nitrogenous bases, alcohols, ATP, and coenzyme A, and can generate the glyceryl moiety during glycolysis. Cholesterol is obtained from the host but nothing is known of sphingolipid origins. Lipid metabolism of the parasite may be associated with alterations in the amounts of octadecenoic fatty acids and cholesterol in the erythrocyte plasma membrane, which in turn are responsible for changes in permeability and fragility. PMID:412602

  11. Parasitic leiomyomas: a systematic review.

    PubMed

    Lete, Iñaki; González, Janire; Ugarte, Lorea; Barbadillo, Nagore; Lapuente, Oihane; Álvarez-Sala, Javier

    2016-08-01

    Parasitic leiomyomas were first described as early as 1909 but are a rare condition. In recent years, due to the rise of laparoscopic surgery and power morcellation, several cases of parasitic leiomyomas associated with this surgical procedure have been reported. A literature search was performed using PubMed, Embase and Google Scholar with the following combination of keywords: leiomyoma OR uterine neoplasms OR uterine myomectomy OR laparoscopy OR hysterectomy OR peritoneal neoplasms AND parasitic. Papers describing parasitic leiomyomas were included. The results of these studies are summarized herein. We retrieved abstracts of 756 papers. Of these, 591 were excluded for not fulfilling the inclusion criteria and 54 were removed as duplicates; after full-text assessment, 8 were rejected for presenting cases of malignancy and finally 103 were included in our systematic review. From these, we present information about 274 patients with parasitic leiomyomas. The mean age of women was 40 years (range 18-79 years); and 154 (56%) had no history of uterine surgery, the others (120, 44%) having had a previous myomectomy or hysterectomy. Of the total, 106 (39%) women had a history of power morcellation. The most frequent clinical symptom was abdominal pain (49%) and the most frequent presentation was disseminated peritoneal leiomyomatosis. While parasitic leiomyoma was first described a century ago, the recent introduction of laparoscopic power morcellation has increased the number of reported cases. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  12. Birds are islands for parasites

    PubMed Central

    Koop, Jennifer A. H.; DeMatteo, Karen E.; Parker, Patricia G.; Whiteman, Noah K.

    2014-01-01

    Understanding the mechanisms driving the extraordinary diversification of parasites is a major challenge in evolutionary biology. Co-speciation, one proposed mechanism that could contribute to this diversity is hypothesized to result from allopatric co-divergence of host–parasite populations. We found that island populations of the Galápagos hawk (Buteo galapagoensis) and a parasitic feather louse species (Degeeriella regalis) exhibit patterns of co-divergence across variable temporal and spatial scales. Hawks and lice showed nearly identical population genetic structure across the Galápagos Islands. Hawk population genetic structure is explained by isolation by distance among islands. Louse population structure is best explained by hawk population structure, rather than isolation by distance per se, suggesting that lice tightly track the recent population histories of their hosts. Among hawk individuals, louse populations were also highly structured, suggesting that hosts serve as islands for parasites from an evolutionary perspective. Altogether, we found that host and parasite populations may have responded in the same manner to geographical isolation across spatial scales. Allopatric co-divergence is likely one important mechanism driving the diversification of parasites. PMID:25099959

  13. Parasitic Pneumonia and Lung Involvement

    PubMed Central

    Cheepsattayakorn, Ruangrong

    2014-01-01

    Parasitic infestations demonstrated a decline in the past decade as a result of better hygiene practices and improved socioeconomic conditions. Nevertheless, global immigration, increased numbers of the immunocompromised people, international traveling, global warming, and rapid urbanization of the cities have increased the susceptibility of the world population to parasitic diseases. A number of new human parasites, such as Plasmodium knowlesi, in addition to many potential parasites, have urged the interest of scientific community. A broad spectrum of protozoal parasites frequently affects the respiratory system, particularly the lungs. The diagnosis of parasitic diseases of airway is challenging due to their wide varieties of clinical and roentgenographic presentations. So detailed interrogations of travel history to endemic areas are critical for clinicians or pulmonologists to manage this entity. The migrating adult worms can cause mechanical airway obstruction, while the larvae can cause airway inflammation. This paper provides a comprehensive review of both protozoal and helminthic infestations that affect the airway system, particularly the lungs, including clinical and roentgenographic presentations, diagnostic tests, and therapeutic approaches. PMID:24995332

  14. Pathology of CNS parasitic infections.

    PubMed

    Pittella, José Eymard Homem

    2013-01-01

    Parasitic infections of the central nervous system (CNS) include two broad categories of infectious organisms: single-celled protozoa and multicellular metazoa. The protozoal infections include malaria, American trypanosomiasis, human African trypanosomiasis, toxoplasmosis, amebiasis, microsporidiasis, and leishmaniasis. The metazoal infections are grouped into flatworms, which include trematoda and cestoda, and roundworms or nematoda. Trematoda infections include schistosomiasis and paragonimiasis. Cestoda infections include cysticercosis, coenurosis, hydatidosis, and sparganosis. Nematoda infections include gnathostomiasis, angiostrongyliasis, toxocariasis, strongyloidiasis, filariasis, baylisascariasis, dracunculiasis, micronemiasis, and lagochilascariasis. The most common route of CNS invasion is through the blood. In some cases, the parasite invades the olfactory neuroepithelium in the nasal mucosa and penetrates the brain via the subarachnoid space or reaches the CNS through neural foramina of the skull base around the cranial nerves or vessels. The neuropathological changes vary greatly, depending on the type and size of the parasite, geographical strain variations in parasitic virulence, immune evasion by the parasite, and differences in host immune response. Congestion of the leptomeninges, cerebral edema, hemorrhage, thrombosis, vasculitis, necrosis, calcification, abscesses, meningeal and perivascular polymorphonuclear and mononuclear inflammatory infiltrate, microglial nodules, gliosis, granulomas, and fibrosis can be found affecting isolated or multiple regions of the CNS, or even diffusely spread. Some infections may be present as an expanding mass lesion. The parasites can be identified by conventional histology, immunohistochemistry, in situ hybridization, and PCR. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Parasites of two native fishes in adjacent Adirondack lakes.

    PubMed

    Bauer, Eric F; Whipps, Christopher M

    2013-08-01

    This survey of parasites in 2 adjacent lakes is the first of its kind in the Adirondack Park of New York State. Wolf Lake is designated as a heritage lake whereas nearby Deer Lake is limnologically similar but has at least 5 introduced fish species. Both lakes have 2 native species, i.e., white sucker (Catostomus commersoni) and redbreast sunfish (Lepomis auritus), which were the focus of this study. Parasite communities of both hosts were surveyed and compared between each lake and were statistically evaluated for differences in species similarity, prevalence, mean intensity, and mean abundance. Between lakes, white suckers had significant differences in the prevalence of 4 parasite species (Myxobolus sp. 2, Myxobolus bibulatus, Octospinifer macilentis, and Pomphorhynchus bulbocoli) and mean abundances of 4 parasites (neascus larvae, Octospinifer macilentis, Pomphorhynchus bulbocoli, and Glaridacris confusus). Redbreast sunfish had significant differences in the prevalence of 3 species (Myxobolus uvuliferis, a coccidian species, and Spinitectus carolini) and differences in parasite mean abundance of 5 species (neascus larvae, Clinostomum marginatum , Leptorhynchoides thecatus, Spinitectus carolini, and Eustrongylides sp.). Differences in component communities between lakes were found and, although the exact causes cannot be determined by this study, we speculate on several possible explanations.

  16. Costs of crowding for the transmission of malaria parasites

    PubMed Central

    Pollitt, Laura C; Churcher, Thomas S; Dawes, Emma J; Khan, Shahid M; Sajid, Mohammed; Basáñez, María-Gloria; Colegrave, Nick; Reece, Sarah E

    2013-01-01

    The utility of using evolutionary and ecological frameworks to understand the dynamics of infectious diseases is gaining increasing recognition. However, integrating evolutionary ecology and infectious disease epidemiology is challenging because within-host dynamics can have counterintuitive consequences for between-host transmission, especially for vector-borne parasites. A major obstacle to linking within- and between-host processes is that the drivers of the relationships between the density, virulence, and fitness of parasites are poorly understood. By experimentally manipulating the intensity of rodent malaria (Plasmodium berghei) infections in Anopheles stephensi mosquitoes under different environmental conditions, we show that parasites experience substantial density-dependent fitness costs because crowding reduces both parasite proliferation and vector survival. We then use our data to predict how interactions between parasite density and vector environmental conditions shape within-vector processes and onward disease transmission. Our model predicts that density-dependent processes can have substantial and unexpected effects on the transmission potential of vector-borne disease, which should be considered in the development and evaluation of transmission-blocking interventions. PMID:23789029

  17. Temporal changes in the prevalence of parasites in two Oregon estuary-dwelling fishes.

    PubMed

    Olson, Robert E; Pierce, Jack R; Jacobson, Kym C; Burreson, Eugene M

    2004-06-01

    The parasite faunas of juvenile English sole (Parophrys vetulus) in 1971-1972 and staghorn sculpin (Leptocottus armatus) in 1971 from Yaquina Bay, Oregon, were compared with faunas found in the same estuary in 1997-2000 (English sole) and 1999-2000 (staghorn sculpin). The 7 most commonly occurring parasites in 1971 were compared with the same species observed during the same month and sampling sites in 1997-2000. Multivariate community analysis of juvenile English sole parasites supported the suggestion that the 1971 parasite data were representative of the early-1970s time period. Four of the parasite species infecting English sole and 6 of those infecting staghorn sculpins had significantly lower prevalences in 1997-2000. Parasite species with significantly lower prevalences also had reduced intensity levels. One parasite (Glugea stephani) of English sole increased in prevalence in the 1997-2000 samples in association with the warm estuarine temperatures during the 1997 El Niño year. Although the causes for the changes in occurrence of other parasites were not determined, ecological changes in Yaquina Bay that may have influenced parasite ecology include apparent changes in the estuary ichthyofauna that occurred between the sampling periods. Such changes could be associated with increases in the number of California sea lions (Zalophus californianus) subsequent to establishment of the Marine Mammal Protection Act in 1972.

  18. The meaning of death: evolution and ecology of apoptosis in protozoan parasites.

    PubMed

    Reece, Sarah E; Pollitt, Laura C; Colegrave, Nick; Gardner, Andy

    2011-12-01

    The discovery that an apoptosis-like, programmed cell death (PCD) occurs in a broad range of protozoan parasites offers novel therapeutic tools to treat some of the most serious infectious diseases of humans, companion animals, wildlife, and livestock. Whilst apoptosis is an essential part of normal development, maintenance, and defence in multicellular organisms, its occurrence in unicellular parasites appears counter-intuitive and has proved highly controversial: according to the Darwinian notion of "survival of the fittest", parasites are expected to evolve strategies to maximise their proliferation, not death. The prevailing, and untested, opinion in the literature is that parasites employ apoptosis to "altruistically" self-regulate the intensity of infection in the host/vector. However, evolutionary theory tells us that at most, this can only be part of the explanation, and other non-mutually exclusive hypotheses must also be tested. Here, we explain the evolutionary concepts that can explain apoptosis in unicellular parasites, highlight the key questions, and outline the approaches required to resolve the controversy over whether parasites "commit suicide". We highlight the need for integration of proximate and functional approaches into an evolutionary framework to understand apoptosis in unicellular parasites. Understanding how, when, and why parasites employ apoptosis is central to targeting this process with interventions that are sustainable in the face of parasite evolution.

  19. The Meaning of Death: Evolution and Ecology of Apoptosis in Protozoan Parasites

    PubMed Central

    Reece, Sarah E.; Pollitt, Laura C.; Colegrave, Nick; Gardner, Andy

    2011-01-01

    The discovery that an apoptosis-like, programmed cell death (PCD) occurs in a broad range of protozoan parasites offers novel therapeutic tools to treat some of the most serious infectious diseases of humans, companion animals, wildlife, and livestock. Whilst apoptosis is an essential part of normal development, maintenance, and defence in multicellular organisms, its occurrence in unicellular parasites appears counter-intuitive and has proved highly controversial: according to the Darwinian notion of “survival of the fittest”, parasites are expected to evolve strategies to maximise their proliferation, not death. The prevailing, and untested, opinion in the literature is that parasites employ apoptosis to “altruistically” self-regulate the intensity of infection in the host/vector. However, evolutionary theory tells us that at most, this can only be part of the explanation, and other non-mutually exclusive hypotheses must also be tested. Here, we explain the evolutionary concepts that can explain apoptosis in unicellular parasites, highlight the key questions, and outline the approaches required to resolve the controversy over whether parasites “commit suicide”. We highlight the need for integration of proximate and functional approaches into an evolutionary framework to understand apoptosis in unicellular parasites. Understanding how, when, and why parasites employ apoptosis is central to targeting this process with interventions that are sustainable in the face of parasite evolution. PMID:22174671

  20. Synchronous attack is advantageous: mixed genotype infections lead to higher infection success in trematode parasites

    PubMed Central

    Karvonen, Anssi; Rellstab, Christian; Louhi, Katja-Riikka; Jokela, Jukka

    2012-01-01

    Co-infecting parasite genotypes typically compete for host resources limiting their fitness. The intensity of such competition depends on whether parasites are reproducing in a host, or using it primarily as a transmission vehicle while not multiplying in host tissues (referred to as ‘competition hypothesis’). Alternatively, simultaneous attack and co-infection by several parasite genotypes might facilitate parasite infection because such a diverse attack could present an additional challenge to host immune defence (referred to as ‘facilitation hypothesis’). We tested the competition hypothesis by comparing the production of transmission stages (cercariae) from snails infected with one or two genotypes of the trematode Diplostomum pseudospathaceum. We found that cercarial production did not differ between the two groups of snails, suggesting lower per genotype production in double infections, and competition for host resources. Second, we tested the facilitation hypothesis by comparing parasite infection success on fishes (proportion of parasites establishing in the host) using cercariae originating from single-infected snails, double-infected snails and artificial mixtures of the single genotypes. In both cases, we found higher infection success when fishes were challenged with two parasite genotypes instead of one, supporting the facilitation hypothesis. Our results suggest that constraints defining the success of multiple genotype infections in parasites with multiple host life cycles include both between-genotype resource competition in the host and performance of host immune defences against a diverse parasite challenge. PMID:21632629

  1. Wildlife parasites: lessons for parasite control in livestock.

    PubMed

    Malan, F S; Horak, I G; de Vos, V; van Wyk, J A

    1997-07-31

    For sustainable livestock production it is suggested that the parasitologist take a leaf out of Nature's book in the search for solutions to the mounting problems concerning parasite control. While the farmer has come to regard all parasites affecting livestock as entirely without benefit, indigenous parasites and diseases are normal and play an essential role as interacting components of a natural environment in an ecosystem such as the 19,000 km2-sized Kruger National Park, Republic of South Africa. The parasites help to select their hosts for fitness and are assisted by predators and intra-species territorial aggression which continually eliminate the weak individuals from the system. It is essential to guard against the introduction of foreign parasites or infectious agents which have no real ecological niche or role in an established ecosystem, however, as they cause untoward interactions, sometimes of a violent nature. The policy must be to block off or, failing that, to control or eliminate these foreign parasites and diseases as far as possible. Often, when Man intervenes in an ecosystem, it leads to stress, overcrowding and stagnation and predisposes to disease and death. Intensification of the system, as in farming units, denies Nature the chance to manage on its own, because of clashing interests with Man. Frank parasitism and disease should almost invariably be seen as indicators of an imbalance in the ecosystem and should be rectified. Chemicals and vaccines should be used to produce sufficient food for all, but without exploiting Nature, or else Nature will be unable to continue catering for Man's needs.

  2. Hosts and parasites as aliens.

    PubMed

    Taraschewski, H

    2006-06-01

    Over the past decades, various free-living animals (hosts) and their parasites have invaded recipient areas in which they had not previously occurred, thus gaining the status of aliens or exotics. In general this happened to a low extent for hundreds of years. With variable frequency, invasions have been followed by the dispersal and establishment of non-indigenous species, whether host or parasite. In the literature thus far, colonizations by both hosts and parasites have not been treated and reviewed together, although both are usually interwoven in various ways. As to those factors permitting invasive success and colonization strength, various hypotheses have been put forward depending on the scientific background of respective authors and on the conspicuousness of certain invasions. Researchers who have tried to analyse characteristic developmental patterns, the speed of dispersal or the degree of genetic divergence in populations of alien species have come to different conclusions. Among parasitologists, the applied aspects of parasite invasions, such as the negative effects on economically important hosts, have long been at the centre of interest. In this contribution, invasions by hosts as well as parasites are considered comparatively, revealing many similarities and a few differences. Two helminths, the liver fluke, Fasciola hepatica, of cattle and sheep and the swimbladder nematode, Anguillicola crassus, of eels are shown to be useful as model parasites for the study of animal invasions and environmental global change. Introductions of F. hepatica have been associated with imports of cattle or other grazing animals. In various target areas, susceptible lymnaeid snails serving as intermediate hosts were either naturally present and/or were introduced from the donor continent of the parasite (Europe) and/or from other regions which were not within the original range of the parasite, partly reflecting progressive stages of a global biota change. In several

  3. Paleoparasitology: the origin of human parasites.

    PubMed

    Araújo, Adauto; Reinhard, Karl; Ferreira, Luiz Fernando; Pucu, Elisa; Chieffi, Pedro Paulo

    2013-09-01

    Parasitism is composed by three subsystems: the parasite, the host, and the environment. There are no organisms that cannot be parasitized. The relationship between a parasite and its host species most of the time do not result in damage or disease to the host. However, in a parasitic disease the presence of a given parasite is always necessary, at least in a given moment of the infection. Some parasite species that infect humans were inherited from pre-hominids, and were shared with other phylogenetically close host species, but other parasite species were acquired from the environment as humans evolved. Human migration spread inherited parasites throughout the globe. To recover and trace the origin and evolution of infectious diseases, paleoparasitology was created. Paleoparasitology is the study of parasites in ancient material, which provided new information on the evolution, paleoepidemiology, ecology and phylogenetics of infectious diseases.

  4. Parasites that cause problems in Malaysia: soil-transmitted helminths and malaria parasites.

    PubMed

    Singh, B; Cox-Singh, J

    2001-12-01

    Malaysia is a developing country with a range of parasitic infections. Indeed, soil-transmitted helminths and malaria parasites continue to have a significant impact on public health in Malaysia. In this article, the prevalence and distribution of these parasites, the problems associated with parasitic infections, the control measures taken to deal with these parasites and implications for the future will be discussed.

  5. Protein S-Glutathionylation in Malaria Parasites

    PubMed Central

    Kehr, Sebastian; Jortzik, Esther; Delahunty, Claire; Yates, John R.; Rahlfs, Stefan

    2011-01-01

    Abstract Aims: Protein S-glutathionylation is a widely distributed post-translational modification of thiol groups with glutathione that can function as a redox-sensitive switch to mediate redox regulation and signal transduction. The malaria parasite Plasmodium falciparum is exposed to intense oxidative stress and possesses the enzymatic system required to regulate protein S-glutathionylation, but despite its potential importance, protein S-glutathionylation has not yet been studied in malaria parasites. In this work we applied a method based on enzymatic deglutathionylation, affinity purification of biotin-maleimide-tagged proteins, and proteomic analyses to characterize the Plasmodium glutathionylome. Results: We identified 493 targets of protein S-glutathionylation in Plasmodium. Functional profiles revealed that the targets are components of central metabolic pathways, such as nitrogen compound metabolism and protein metabolism. Fifteen identified proteins with important functions in metabolic pathways (thioredoxin reductase, thioredoxin, thioredoxin peroxidase 1, glutathione reductase, glutathione S-transferase, plasmoredoxin, mitochondrial dihydrolipoamide dehydrogenase, glutamate dehydrogenase 1, glyoxalase I and II, ornithine δ-aminotransferase, lactate dehydrogenase, glyceraldehyde 3-phosphate dehydrogenase [GAPDH], pyruvate kinase [PK], and phosphoglycerate mutase) were further analyzed to study their ability to form mixed disulfides with glutathione. We demonstrate that P. falciparum GAPDH, PK, and ornithine δ-aminotransferase are reversibly inhibited by S-glutathionylation. Further, we provide evidence that not only P. falciparum glutaredoxin 1, but also thioredoxin 1 and plasmoredoxin are able to efficiently catalyze protein deglutathionylation. Innovation: We used an affinity-purification based proteomic approach to characterize the Plasmodium glutathionylome. Conclusion: Our results indicate a wide regulative use of S-glutathionylation in the

  6. Sublethal responses of largemouth bass to parasites and organochlorines

    SciTech Connect

    MacRury, N.K.; Johnson, B.M.

    1999-05-01

    Largemouth bass (Micropterus salmoides) at the Rocky Mountain Arsenal National Wildlife Refuge (RMA) experience chronic organochlorine exposures and parasitism by nematodes (Contracaecum spiculigerum) and digenean flukes (Posthodiplostomum minimum centrarchi). The authors investigated the influences of nematode intensity, fluke intensity, and whole-body organochlorine concentrations on growth of juvenile RMA bass. Lifetime growth, or age-specific lengths, of bass in three RMA lakes were within the range observed for bass in five reference lakes. However, interlake comparisons can be confounded by differing environmental conditions. Therefore, they conducted mesocosm and laboratory studies to compare growth, consumption, and feeding behavior between RMA bass and bass that had little contaminant or parasite exposure. Mean growth rates of RMA bass were 45% lower compared with hatchery bass in experimental ponds. However, regression analysis revealed that parasite and organochlorine burdens were not negatively associated with either short-term growth or age-specific lengths of RMA bass. Hatchery bass growth was likely higher due to their experience with culture pond conditions. In feeding trials, RMA bass exhibited similar food conversion efficiency and consumption rates and significantly elevated feeding activity compared with hatchery bass. This research demonstrates that current parasite and organochlorine loads had benign influences on growth of juvenile RMA bass.

  7. Host densities as determinants of abundance in parasite communities

    PubMed Central

    Arneberg, P.; Skorping, A.; Grenfell, B.; Read, A. F.

    1998-01-01

    Several epidemiological models predict a positive relationship between host population density and abundance of directly transmitted macroparasites. Here, we generalize these, and test the prediction by a comparative study. We used data on communities of gastrointestinal strongylid nematodes from 19 mammalian species, representing examination of 6670 individual hosts. We studied both the average abundance of all strongylid nematodes within a host species, and the two components of abundance, prevalence and intensity. The effects of host body weight, diet, fecundity and age at maturity and parasite body size were controlled for directly, and the phylogenetically independent contrast method was used to control for confounding factors more generally. Host population density and average parasite abundance were strongly positively correlated within mammalian taxa, and across all species when the effects of host body weight were controlled for. Controlling for other variables did not change this. Even when looking at single parasite species occurring in several host species, abundance was highest in the host species with the highest population density. Prevalence and intensity showed similar patterns. These patterns provide the first macroecological evidence consistent with the prediction that transmission rates depend on host population density in natural parasite communities.

  8. [Advances on antitumor effect of parasites].

    PubMed

    Wang, Su-wen; Sun, Jun

    2014-08-01

    Immune response induced by parasites could inhibit tumor growth and promote apoptosis of tumor cells. The investigation into this character will provide new insights on the anti-tumor effect of parasites. The mechanism of parasite immune evasion may provide a reference for tumor research. Furthermore, some anti-parasitic drugs have shown antitumor effect indicating that the development of antitumor drugs may get inspiration from anti-parasitic drug studies.

  9. Massive parasitism by Gussevia tucunarense (Platyhelminthes: Monogenea: Dactylogyridae) in fingerlings of bujurqui-tucunare cultured in the Peruvian Amazon.

    PubMed

    Mathews, Patrick D; Mertins, Omar; Mathews, John P D; Orbe, Rosa I

    2013-06-01

    A high infestation of the monogenean Gussevia tucunarense in a cultivation of bujurqui-tucunare was reported. The prevalence was 100%. The mean intensity and abundance of the parasite was 164.4 of parasites per individual. This is the first report of a high infestation by G. tucunarense in C. semifasciatus cultured from the Peruvian Amazon.

  10. PARASITIC INTERFERENCE IN LONG BASELINE OPTICAL INTERFEROMETRY: REQUIREMENTS FOR HOT JUPITER-LIKE PLANET DETECTION

    SciTech Connect

    Matter, A.; Lopez, B.; Lagarde, S.; Danchi, W. C.; Navarro, R.

    2009-12-01

    The observable quantities in optical interferometry, which are the modulus and the phase of the complex visibility, may be corrupted by parasitic fringes superimposed on the genuine fringe pattern. These fringes are due to an interference phenomenon occurring from stray light effects inside an interferometric instrument. We developed an analytical approach to better understand this phenomenon when stray light causes cross talk between beams. We deduced that the parasitic interference significantly affects the interferometric phase and thus the associated observables including the differential phase and the closure phase. The amount of parasitic flux coupled to the piston between beams appears to be very influential in this degradation. For instance, considering a point-like source and a piston ranging from lambda/500 to lambda/5 in the L band (lambda = 3.5 mum), a parasitic flux of about 1% of the total flux produces a parasitic phase reaching at most one-third of the intrinsic phase. The piston, which can have different origins (instrumental stability, atmospheric perturbations, etc.), thus amplifies the effect of parasitic interference. According to the specifications of piston correction in space or at ground level (respectively lambda/500 approx 2 nm and lambda/30 approx 100 nm), the detection of hot Jupiter-like planets, one of the most challenging aims for current ground-based interferometers, limits parasitic radiation to about 5% of the incident intensity. This was evaluated by considering different types of hot Jupiter synthetic spectra. Otherwise, if no fringe tracking is used, the detection of a typical hot Jupiter-like system with a solar-like star would admit a maximum level of parasitic intensity of 0.01% for piston errors equal to lambda/15. If the fringe tracking specifications are not precisely observed, it thus appears that the allowed level of parasitic intensity dramatically decreases and may prevent the detection. In parallel, the calibration

  11. Parasitic polymorphism of Coccidioides spp

    PubMed Central

    2014-01-01

    Background Coccidioides spp. is the ethiological agent of coccidioidomycosis, an infection that can be fatal. Its diagnosis is complicated, due to that it shares clinical and histopathological characteristics with other pulmonary mycoses. Coccidioides spp. is a dimorphic fungus and, in its saprobic phase, grows as a mycelium, forming a large amount of arthroconidia. In susceptible persons, arthroconidia induce dimorphic changes into spherules/endospores, a typical parasitic form of Coccidioides spp. In addition, the diversity of mycelial parasitic forms has been observed in clinical specimens; they are scarcely known and produce errors in diagnosis. Methods We presented a retrospective study of images from specimens of smears with 15% potassium hydroxide, cytology, and tissue biopsies of a histopathologic collection from patients with coccidioidomycosis seen at a tertiary-care hospital in Mexico City. Results The parasitic polymorphism of Coccidioides spp. observed in the clinical specimens was as follows: i) spherules/endospores in different maturation stages; ii) pleomorphic cells (septate hyphae, hyphae composed of ovoid and spherical cells, and arthroconidia), and iii) fungal ball formation (mycelia with septate hyphae and arthroconidia). Conclusions The parasitic polymorphism of Coccidioides spp. includes the following: spherules/endospores, arthroconidia, and different forms of mycelia. This knowledge is important for the accurate diagnosis of coccidioidomycosis. In earlier studies, we proposed the integration of this diversity of forms in the Coccidioides spp. parasitic cycle. The microhabitat surrounding the fungus into the host would favor the parasitic polymorphism of this fungus, and this environment may assist in the evolution toward parasitism of Coccidioides spp. PMID:24750998

  12. Host-parasite biology in the real world: the field voles of Kielder.

    PubMed

    Turner, A K; Beldomenico, P M; Bown, K; Burthe, S J; Jackson, J A; Lambin, X; Begon, M

    2014-07-01

    Research on the interactions between the field voles (Microtus agrestis) of Kielder Forest and their natural parasites dates back to the 1930s. These early studies were primarily concerned with understanding how parasites shape the characteristic cyclic population dynamics of their hosts. However, since the early 2000s, research on the Kielder field voles has expanded considerably and the system has now been utilized for the study of host-parasite biology across many levels, including genetics, evolutionary ecology, immunology and epidemiology. The Kielder field voles therefore represent one of the most intensely and broadly studied natural host-parasite systems, bridging theoretical and empirical approaches to better understand the biology of infectious disease in the real world. This article synthesizes the body of work published on this system and summarizes some important insights and general messages provided by the integrated and multidisciplinary study of host-parasite interactions in the natural environment.

  13. Parasitism can be a confounding factor in assessing the response of zebra mussels to water contamination.

    PubMed

    Minguez, Laëtitia; Buronfosse, Thierry; Beisel, Jean-Nicolas; Giambérini, Laure

    2012-03-01

    Biological responses measured in aquatic organisms to monitor environmental pollution could be also affected by different biotic and abiotic factors. Among these environmental factors, parasitism has often been neglected even if infection by parasites is very frequent. In the present field investigation, the parasite infra-communities and zebra mussel biological responses were studied up- and downstream a waste water treatment plant in northeast France. In both sites, mussels were infected by ciliates and/or intracellular bacteria, but prevalence rates and infection intensities were different according to the habitat. Concerning the biological responses differences were observed related to the site quality and the infection status. Parasitism affects both systems but seemed to depend mainly on environmental conditions. The influence of parasites is not constant, but remains important to consider it as a potential confounding factor in ecotoxicological studies. This study also emphasizes the interesting use of integrative indexes to synthesize data set.

  14. Attenuated reproduction of Strombus gigas by an Apicomplexa: Emeriidae-like parasite in the digestive gland.

    PubMed

    Baqueiro Cardenas, Erick; Montero, Jorge; Frenkiel, Liliane; Aldana Aranda, Dalila

    2012-07-01

    An intense and generalized sporozoan infection was detected in every population of the queen conch, Strombus gigas through the Caribbean. In this contribution we establish the relationship between occurrences of an Apicomplexa: Emeriidae-like organism and reproductive activity at San Andres archipelago, Colombia. Occurrence of the parasites was estimated counting the feeding stage Merozoites and cysts Sporozoites at 40× magnification. Nonmetric multidimensional scaling analysis (NMDS) was made to correlate the parasites stages abundance with frequency of the reproductive stages. Gametogenesis and spawning were always low coinciding with high numbers of Merozoites, a positive correlation was established between parasite abundance with reabsorption and undifferentiated stages, and negative correlation was observed between parasite abundance with maturity and spawning stages. The nonmetric multidimensional scaling (NMDS) shows that gametogenesis, maturity and spawning increase as the number of parasites decrease, factor that could be threatening reproduction of S. gigas through the Caribbean. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. Parasites, pets, and people.

    PubMed

    Marx, M B

    1991-03-01

    It is important for the family physician to understand that patients' relationships with their pets play an important role in helping maintain mental and physical health yet provide the potential for causing illness in the patient. Toxocara canis (dog roundworm) and Toxocara cati (cat roundworm) are the ascarids most commonly responsible for VLM and ocular larva migrans in humans. These roundworms live in their adult stage in the small intestine of the dog and cat where their eggs are passed in the feces. The eggs containing the infective larva are very sticky, thus an infant crawling around on the floor can easily pick these up on fingers that almost invariably end up in the mouth. Infections are usually mild and asymptomatic but with a persistent eosinophilia. Ocular larva migrans is the form usually occurring in older children and adults. Some public health veterinarians recommend that a puppy or kitten should not be obtained as a companion for a child who is not old enough to read, thus bypassing the crawling and toddler stages. Hookworm eggs, shed in the feces of infected dogs or cats, develop into the infective second stage within a week. Humans are usually infected when bare areas of skin such as bare feet or the torso come in contact with soil contaminated with the larvae. The second-stage larvae are able to penetrate the intact skin of humans and the foot pads of dogs and cats. In the United States, the common dog hookworm, A. caninum, is a widespread parasite. Human intestinal ancylostomiasis caused by this species is rare, with only six cases recorded in the literature. Infection in humans or animals by the common tapeworm of dogs and cats (Dipylidium caninum) requires ingestion of the intermediate host, the dog or cat flea containing the larva (cysticercoids) of the agent. Many cases in humans are asymptomatic. Dipylidiasis affects mainly infants and young children who may swallow a flea that hops up while the infant is crawling on the floor or fondling

  16. Remote Sensing of Parasitic Nematodes in Plants

    NASA Technical Reports Server (NTRS)

    Lawrence, Gary W.; King, Roger; Kelley, Amber T.; Vickery, John

    2007-01-01

    A method and apparatus for remote sensing of parasitic nematodes in plants, now undergoing development, is based on measurement of visible and infrared spectral reflectances of fields where the plants are growing. Initial development efforts have been concentrated on detecting reniform nematodes (Rotylenchulus reniformis) in cotton plants, because of the economic importance of cotton crops. The apparatus includes a hand-held spectroradiometer. The readings taken by the radiometer are processed to extract spectral reflectances at sixteen wavelengths between 451 and 949 nm that, taken together, have been found to be indicative of the presence of Rotylenchulus reniformis. The intensities of the spectral reflectances are used to estimate the population density of the nematodes in an area from which readings were taken.

  17. Parasite co-infection and interaction as drivers of host heterogeneity.

    PubMed

    Cattadori, I M; Boag, B; Hudson, P J

    2008-03-01

    We examined the hypothesis that the interaction between concomitant infecting parasites modifies host susceptibility, parasite intensity and the pattern of parasite distribution within the host population. We used a 26 year time series of three common parasites in a natural population of rabbits: two gastrointestinal nematodes (Trichostrongylus retortaeformis and Graphidium strigosum) and the immunosuppressive myxoma virus. The frequency distribution of nematodes in the host population and the relationship between host age and nematode intensity were explored in rabbits with either single or dual nematode infections and rabbits infected with the nematodes and myxoma virus. The aggregation of T. retortaeformis and G. strigosum among the rabbits varied with the nature of the co-infection both in male and female hosts. The two nematodes exhibited different age-intensity profiles: G. strigosum intensity increased exponentially with host age while T. retortaeformis intensity exhibited a convex shape. The presence of a secondary infection did not change the age-intensity profile for G. strigosum but for T. retortaeformis co-infection (either both nematodes or myxoma-nematodes) resulted in significantly greater intensities in adult hosts. Results suggest that multi-species infections contributed to aggregation of parasites in the host population and to seasonal variation in intensity, but also enhanced differences in parasitism between sexes. This effect was apparent for T. retortaeformis, which appears to elicit a strong acquired immune response but not for G. strigosum which does not produce any evident immune reaction. We concluded that concomitant infections mediated by host immunity are important in modifying host susceptibility and influencing heterogeneity amongst individual hosts.

  18. Leptin, a tool of parasites?

    PubMed Central

    Lõhmus, Mare; Moalem, Sharon; Björklund, Mats

    2012-01-01

    One common physiological phenomenon that is involved both in infectious and in malignant processes is the reduction in appetite: disease anorexia. An increase in plasma levels of leptin with inflammation is thought to be involved in this process. However, from an evolutionary perspective, in certain cases, it would be more adaptive for an internal parasite to stimulate the appetite of the host instead of causing its suppression. We tested whether a parasitic infection with the larvae of the helminth parasite Taenia taeniaformis affects the levels of appetite-regulating proteins, such as leptin, ghrelin and neuropeptide-Y (NPY) in wild yellow-necked mouse (Apodemus flavicollis). We found that infected mice had lower plasma levels of leptin and increased levels of NPY than the uninfected subjects. Ghrelin levels were not associated with the occurrence of the parasites; however, these levels strongly correlated with the levels of NPY. This study suggests a possible manipulation by parasitic larvae of appetite regulation in infected subjects. PMID:22740641

  19. Host-parasite relationships of monogeneans in gills of Astyanax altiparanae and Rhamdia quelen of the São Francisco Verdadeiro River, Brazil.

    PubMed

    Ferrari-Hoeinghaus, A P; Takemoto, R M; Oliveira, L C; Makrakis, M C; Baumgartner, G

    2006-12-01

    This study investigates the ecology of monogenean gill parasites of Aslyanax altiparanae Garutti & Britski, 2000 and Rhamdia quelen (Quoy & Gaimard, 1824) in a stretch of the Sao Francisco Verdadeiro River, Parana, Brazil. Statistical and ecological indices were used to examine observed levels of parasitism in relation to host and environmental characteristics. A. altiparance and R. quelen had infestation intensities of 2.8 and 23.1 parasites per fish, respectively. The only significant environmental influence was observed at the upstream station for R. quelen. For both host species, parasitized and non-parasitized individuals presented similar weight-ength relationships. Parasitized individuals had dispersed K,, values indicating abnormal conditions. The low levels of parasitism observed in this study suggest that the environment is relatively undisturbed. Additional studies should compare these two species and their respective parasites following completion of the hydroelectric headquarters planned for construction in this stretch of the Sao Francisco Verdoadeiro River.

  20. A lack of crowding? Body size does not decrease with density for two behavior-manipulating parasites

    USGS Publications Warehouse

    Weinersmith, KL; Warinner, Chloe B.; Tan, Virgina; Harris, David J.; Mora, Adrienne B.; Kuris, Armand M.; Lafferty, Kevin D.; Hechinger, Ryan F.

    2014-01-01

    For trophically transmitted parasites that manipulate the phenotype of their hosts, whether the parasites do or do not experience resource competition depends on such factors as the size of the parasites relative to their hosts, the intensity of infection, the extent to which parasites share the cost of defending against the host’s immune system or manipulating their host, and the extent to which parasites share transmission goals. Despite theoretical expectations for situations in which either no, or positive, or negative density-dependence should be observed, most studies document only negative density-dependence for trophically transmitted parasites. However, this trend may be an artifact of most studies having focused on systems in which parasites are large relative to their hosts. Yet, systems are common where parasites are small relative to their hosts, and these trophically transmitted parasites may be less likely to experience resource limitation. We looked for signs of density-dependence in Euhaplorchis californiensis (EUHA) and Renicola buchanani (RENB), two manipulative trematode parasites infecting wild-caught California killifish (Fundulus parvipinnis). These parasites are small relative to killifish (suggesting resources are not limiting), and are associated with changes in killifish behavior that are dependent on parasite-intensity and that increase predation rates by the parasites’ shared final host (indicating the possibility for cost sharing). We did not observe negative density-dependence in either species, indicating that resources are not limiting. In fact, observed patterns indicate possible mild positive density-dependence for EUHA. Although experimental confirmation is required, our findings suggest that some behavior-manipulating parasites suffer no reduction in size, and may even benefit when "crowded" by conspecifics.

  1. Response of Flour Beetles to Multiple Stressors of Parasitic (Hymenolepis diminuta), Environmental (Diatomaceous Earth), and Host (Reproduction) Origin.

    PubMed

    Shostak, Allen W; Van Buuren, Kala G; Cook, Ranon

    2015-08-01

    Organisms face a multitude of potential stressors, and the way these stressors interact can provide insights into underlying biological processes. This study examined the flour beetle Tribolium confusum and its survival, net fecundity, and surface-seeking behavior in response to combinations of stressors from 3 categories. Infection by the cestode Hymenolepis diminuta provided a stress of parasitic origin. Exposure to diatomaceous earth (DE) provided a stress of environmental origin. Use of virgin and mated beetles evaluated reproduction as a stress of host origin. Single and multiple exposure of beetles to parasite eggs achieved a maximum mean abundance of 21 parasites/beetle and a maximum intensity of 90 parasites in an individual beetle. DE reduced initial parasite establishment, but did not directly affect survival of parasites after their establishment in the host. A rehydration technique was used to recover parasites from dead beetles, enabling this to be the first study to correlate H. diminuta intensity at time of death directly to mortality of T. confusum. A dichotomous intensity-mortality relationship was observed in 8% DE, whereby lightly infected (<20 parasites) hosts were killed by DE in an intensity-independent manner, but more heavily infected hosts were killed in an intensity-dependent manner. Host mating status did not affect host survival, but there were interactions among mating status, parasitism, and DE on net fecundity and surface-seeking behavior. However, these effects were minor compared to the host mortality that occurred when parasite abundance and DE concentration were both high. The aggregated distribution of T. confusum in beetles, the difficulty of achieving high mean abundances, and an apparent need for the stressors to have strong effects individually if they are to have enhanced effects when in combination, suggests that exposure to multiple stressors would seriously impact only a small proportion of the host population.

  2. Host-parasite interactions: Marine bivalve molluscs and protozoan parasites, Perkinsus species.

    PubMed

    Soudant, Philippe; E Chu, Fu-Lin; Volety, Aswani

    2013-10-01

    This review assesses and examines the work conducted to date concerning host and parasite interactions between marine bivalve molluscs and protozoan parasites, belonging to Perkinsus species. The review focuses on two well-studied host-parasite interaction models: the two clam species, Ruditapes philippinarum and R. decussatus, and the parasite Perkinsus olseni, and the eastern oyster, Crassostrea virginica, and the parasite Perkinsus marinus. Cellular and humoral defense responses of the host in combating parasitic infection, the mechanisms (e.g., antioxidant enzymes, extracellular products) employed by the parasite in evading host defenses as well as the role of environmental factors in modulating the host-parasite interactions are described.

  3. Do captive conditions favor shedding of parasites in the reared Atlantic bluefin tuna (Thunnus thynnus)?

    PubMed

    Mladineo, I; Segvić, T; Petrić, M

    2011-01-01

    Tuna (Thunnus spp.) has been characterized by long distance migrations, highly predatory behavior and longevity, all of which in turn, enable infections with a wide spectrum of different parasitic groups, reflecting in a remarkable diversity of tuna parasite communities. Since 2003, we have been monitoring parasite communities of Atlantic bluefin tuna (Thunnus thynnus) that are caught from the wild and transferred into cages during spring-summer months, as well as assemblages in fish that exit rearing cycle during the winter harvest period after 1.5 years. Interestingly in reared tuna, parasitic populations exhibit a significant decreasing trend at the end of the rearing cycle, rarely observed in other intensive productions that represent a suitable environment for the emergence, establishment and transmission of pathogens. In order to assess epizootiological behavior of tuna parasites assemblages at the beginning (B group) and at the end (A group) of 1.5 year rearing cycle, we examined data on parasite prevalence and abundance over 4 years. The aim was to evaluate parasite diversity indices and emerging differences between newly caught and harvested fish, as well as community compositions and their nestedness in respect to the event in the rearing cycle (capture or harvest time). In order to be able to predict classification of tuna in two categories (newly caught or heavily infected and harvested or less infected fish), based on empirical didymozoids abundances and year of sampling, we built a decision tree model. Results suggest that specificities of parasite assemblages and their dynamics in tuna before and after farming have no similar precedents in aquaculture. A trend of parasitic pauperization repeating in each rearing cycle over four-years time, in once diverse and species rich parasite communities is observed, however, structures of both B and A group rearing assemblages remain nested, with the same species being core parasites (Didymosulcus katsuwonicola

  4. Taming Parasites by Tailoring Them

    PubMed Central

    Ren, Bingjian; Gupta, Nishith

    2017-01-01

    The next-generation gene editing based on CRISPR (clustered regularly interspaced short palindromic repeats) has been successfully implemented in a wide range of organisms including some protozoan parasites. However, application of such a versatile game-changing technology in molecular parasitology remains fairly underexplored. Here, we briefly introduce state-of-the-art in human and mouse research and usher new directions to drive the parasitology research in the years to come. In precise, we outline contemporary ways to embolden existing apicomplexan and kinetoplastid parasite models by commissioning front-line gene-tailoring methods, and illustrate how we can break the enduring gridlock of gene manipulation in non-model parasitic protists to tackle intriguing questions that remain long unresolved otherwise. We show how a judicious solicitation of the CRISPR technology can eventually balance out the two facets of pathogen-host interplay. PMID:28730142

  5. Isoprenoid metabolism in apicomplexan parasites

    PubMed Central

    Imlay, Leah; Odom, Audrey R.

    2014-01-01

    Apicomplexan parasites include some of the most prevalent and deadly human pathogens. Novel antiparasitic drugs are urgently needed. Synthesis and metabolism of isoprenoids may present multiple targets for therapeutic intervention. The apicoplast-localized methylerythritol phosphate (MEP) pathway for isoprenoid precursor biosynthesis is distinct from the mevalonate (MVA) pathway used by the mammalian host, and this pathway is apparently essential in most Apicomplexa. In this review, we discuss the current field of research on production and metabolic fates of isoprenoids in apicomplexan parasites, including the acquisition of host isoprenoid precursors and downstream products. We describe recent work identifying the first MEP pathway regulator in apicomplexan parasites, and introduce several promising areas for ongoing research into this well-validated antiparasitic target. PMID:25893156

  6. Parasitic diseases of the pleura.

    PubMed

    Lal, Chitra; Huggins, John Terrill; Sahn, Steven A

    2013-05-01

    Parasitic infections are prevalent in certain parts of the world and may cause pleural involvement, which often goes unrecognized. Common parasites involving the pleura include Entamoeba histolytica, Echinococcus granulosus and Paragonimus westermani. Amebiasis can cause empyema with "anchovy sauce" pus, reactive pleural effusions and bronchopleural fistula with hydropneumothorax. Echinococcosis may result in pleural thickening, pneumothorax, secondary pleural hydatidosis and pleural effusions. Paragonimiasis may cause chylous and cholesterol pleural effusions, pleural thickening and pneumothorax. Less commonly, pulmonary eosinophilia, or Loeffler's syndrome, caused by Ascaris lumbricoides, Ancylostoma duodenale and Necator americanus and tropical pulmonary eosinophilia caused by Wuchereria bancrofti and Brugia malayi may involve the pleura. This article provides a comprehensive review of parasitic infections involving the pleura. A high index of suspicion in the appropriate clinical setting is required to facilitate prompt diagnosis and treatment of these diseases.

  7. Transcript maturation in apicomplexan parasites

    PubMed Central

    Suvorova, Elena S.; White, Michael W.

    2014-01-01

    Summary The complex life cycles of apicomplexan parasites are associated with dynamic changes of protein repertoire. In Toxoplasma gondii, global analysis of gene expression demonstrates that dynamic changes in mRNA levels unfold in a serial cascade during asexual replication and up to 50% of encoded genes are unequally expressed in development. Recent studies indicate transcription as well as mRNA processing have important roles in fulfilling the “just-in-time” delivery of proteins to parasite growth and development. The prominence of post-transcriptional mechanisms in the Apicomplexa was demonstrated by mechanistic studies of the critical RNA-binding proteins and regulatory kinases. However, it is still early in our understanding of how transcription and post-transcriptional mechanisms are balanced to produce adequate numbers of specialized forms that is required to complete the parasite life cycle. PMID:24934558

  8. Patterns of gastrointestinal parasitism among five sympatric prairie carnivores: are males reservoirs?

    PubMed

    Wirsing, Aaron J; Azevedo, Fernando C C; Larivière, Serge; Murray, Dennis L

    2007-06-01

    Male vertebrates are believed to be disproportionately vulnerable to parasites, but empirical support for this contention is mixed. We tested the hypothesis of higher levels of parasitism in males with the use of counts of gastrointestinal helminths in 5 sympatric mammalian carnivores (American badgers, coyotes, red foxes, raccoons, striped skunks) from central Saskatchewan. Parasite burdens for females and males of each host species were compared with the use of prevalence (percentage of hosts infected), intensity (parasites per infected host), and overdispersion (proportion of heavily infected hosts that were male). Of 30 comparisons (13 each for prevalence and intensity, 4 for overdispersion), male bias was detected 8 times (27%), whereas female bias was detected only once (3%), adding some support to the notion that male mammals are more susceptible to parasitism. However, most of the statistical comparisons we undertook revealed no sexual bias (n=21, 70%), suggesting that differential patterns of infection are not ubiquitous in mammals. Moreover, when detected, the magnitude and direction of bias varied among host species, helminth species, and metrics of infection. We conclude that sympatric and ecologically similar mammal species will not always share the tendency for males to be more susceptible to parasitism, and that studies incorporating multiple parasites and metrics of infection are more likely to detect sex bias.

  9. Parasitism by Monogenoidea in Piaractus mesopotamicus (Characiformes, Characidae) cultivated in Paraná River (Brazil).

    PubMed

    Leão, M S L; Justo, M C N; Bueno, G W; Cohen, S C; São Clemente, S C

    2017-11-01

    This study investigated the occurrence, prevalence, mean abundance and mean intensity of monogenoidean parasites in Piaractus mesopotamicus farmed in cages in the reservoir of the Itaipu Hydroelectric Power Station, Paraná River, Brazil. The parasite distribution pattern and the correlation of prevalence and abundance with the total length of hosts were also investigated. Four monogenoidean species were collected: Anacanthorus penilabiatus, A. toledoensis, Mymarothecium ianwhitingtoni and M. viatorum. All the parasites collected in P. mesopotamicus showed the typical aggregated distribution pattern, and the abundance and the prevalence did not shown any correlation with the total length of hosts.

  10. Parasites and immunotherapy: with or against?

    PubMed

    Yousofi Darani, Hossein; Yousefi, Morteza; Safari, Marzieh; Jafari, Rasool

    2016-06-01

    Immunotherapy is a sort of therapy in which antibody or antigen administrates to the patient in order to treat or reduce the severity of complications of disease. This kind of treatment practiced in a wide variety of diseases including infectious diseases, autoimmune disorders, cancers and allergy. Successful and unsuccessful immunotherapeutic strategies have been practiced in variety of parasitic infections. On the other hand parasites or parasite antigens have also been considered for immunotherapy against other diseases such as cancer, asthma and multiple sclerosis. In this paper immunotherapy against common parasitic infections, and also immunotherapy of cancer, asthma and multiple sclerosis with parasites or parasite antigens have been reviewed.

  11. Parasites, emerging disease and wildlife conservation.

    PubMed

    Thompson, R C A; Lymbery, A J; Smith, A

    2010-08-15

    In this review some emerging issues of parasite infections in wildlife, particularly in Australia, are considered. We discuss the importance of understanding parasite biodiversity in wildlife in terms of conservation, the role of wildlife as reservoirs of parasite infection, and the role of parasites within the broader context of the ecosystem. Using a number of parasite species, the value of undertaking longitudinal surveillance in natural systems using non-invasive sampling and molecular tools to characterise infectious agents is illustrated in terms of wildlife health, parasite biodiversity and ecology. Copyright 2010 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

  12. The Geological Record of Parasitic Nematode Evolution.

    PubMed

    Poinar, George O

    2015-01-01

    This chapter discusses the evolutionary history of nematode parasites of invertebrates, vertebrates and plants based on fossil remains in amber, stone and coprolites dating from the Palaeozoic to the Holocene. The earliest parasitic nematode is a primitive plant parasite from the Devonian. Fossil invertebrate-parasitic nematodes first appeared in the Early Cretaceous, while the earliest fossil vertebrate-parasitic nematodes are from Upper Triassic coprolites. Specific examples of fossil nematode parasites over time are presented, along with views on the origin and evolution of nematodes and their hosts. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Status of gastrointestinal parasites in Red Panda of Nepal

    PubMed Central

    Shrestha, Saroj; Kunwar, Ajaya Jang; Acharya, Sakshi; Jnawali, Shant Raj; Acharya, Krishna Prasad

    2017-01-01

    Red pandas are known to be highly susceptible to endoparasites, which can have a prominent impact on the population dynamics of this endangered species. There are very limited published reports on prevalence and risk of parasites in wild populations of red panda, especially localized reports. This study attempts to provide an in-depth insight of the status of endoparasites in red pandas, which is critical for strengthening conservation efforts. A total of 272 fecal samples were collected through systematic sampling across the red panda distribution range in Nepal and coprological examination was completed using standard techniques. It was followed by an estimation of prevalence and mean intensity of parasites, as well as statistical analysis, which was carried out using R statistical software. Parasite prevalence was documented in 90.80% (n = 247) out of 272 samples examined which includes seven different species along with three genera of parasites belonging to Protozoans (3 species), Cestodes (1 genus, 1 species) and Nematodes (2 genera, 3 species). Nematodes predominated in all infected samples (87.62%). Prevalence of Ancyclostoma duodenale (n = 227, 70.06%), having a mean intensity of 3.45 ± 2.88 individuals per sample, was observed, followed by Ascaris lumbricoides (n = 19, 5.86%) and Entamoeba histolytica (n = 24, 7.41%). Eight variables for assessing the determinants of infestation were tested: protected areas; non-protected areas; aspect; elevation; slope; and distance to water sources, herding stations, and settlements. Only the settlement displayed significant association (β = −1534e−04, t =  − 2.192, p = 0.0293) though each parasite species displayed dissimilar association with different variables. This study indicates the urgent need of improving existing herding practice through habitat zonation, rotational grazing, medication of livestock, and prohibition of open defecation within and around red panda habitat. PMID:28894643

  14. Status of gastrointestinal parasites in Red Panda of Nepal.

    PubMed

    Bista, Damber; Shrestha, Saroj; Kunwar, Ajaya Jang; Acharya, Sakshi; Jnawali, Shant Raj; Acharya, Krishna Prasad

    2017-01-01

    Red pandas are known to be highly susceptible to endoparasites, which can have a prominent impact on the population dynamics of this endangered species. There are very limited published reports on prevalence and risk of parasites in wild populations of red panda, especially localized reports. This study attempts to provide an in-depth insight of the status of endoparasites in red pandas, which is critical for strengthening conservation efforts. A total of 272 fecal samples were collected through systematic sampling across the red panda distribution range in Nepal and coprological examination was completed using standard techniques. It was followed by an estimation of prevalence and mean intensity of parasites, as well as statistical analysis, which was carried out using R statistical software. Parasite prevalence was documented in 90.80% (n = 247) out of 272 samples examined which includes seven different species along with three genera of parasites belonging to Protozoans (3 species), Cestodes (1 genus, 1 species) and Nematodes (2 genera, 3 species). Nematodes predominated in all infected samples (87.62%). Prevalence of Ancyclostoma duodenale (n = 227, 70.06%), having a mean intensity of 3.45 ± 2.88 individuals per sample, was observed, followed by Ascaris lumbricoides (n = 19, 5.86%) and Entamoeba histolytica (n = 24, 7.41%). Eight variables for assessing the determinants of infestation were tested: protected areas; non-protected areas; aspect; elevation; slope; and distance to water sources, herding stations, and settlements. Only the settlement displayed significant association (β = -1534e-04, t =  - 2.192, p = 0.0293) though each parasite species displayed dissimilar association with different variables. This study indicates the urgent need of improving existing herding practice through habitat zonation, rotational grazing, medication of livestock, and prohibition of open defecation within and around red panda habitat.

  15. Genome-wide identification of molecular mimicry candidates in parasites.

    PubMed

    Ludin, Philipp; Nilsson, Daniel; Mäser, Pascal

    2011-03-08

    Among the many strategies employed by parasites for immune evasion and host manipulation, one of the most fascinating is molecular mimicry. With genome sequences available for host and parasite, mimicry of linear amino acid epitopes can be investigated by comparative genomics. Here we developed an in silico pipeline for genome-wide identification of molecular mimicry candidate proteins or epitopes. The predicted proteome of a given parasite was broken down into overlapping fragments, each of which was screened for close hits in the human proteome. Control searches were carried out against unrelated, free-living eukaryotes to eliminate the generally conserved proteins, and with randomized versions of the parasite proteins to get an estimate of statistical significance. This simple but computation-intensive approach yielded interesting candidates from human-pathogenic parasites. From Plasmodium falciparum, it returned a 14 amino acid motif in several of the PfEMP1 variants identical to part of the heparin-binding domain in the immunosuppressive serum protein vitronectin. And in Brugia malayi, fragments were detected that matched to periphilin-1, a protein of cell-cell junctions involved in barrier formation. All the results are publicly available by means of mimicDB, a searchable online database for molecular mimicry candidates from pathogens. To our knowledge, this is the first genome-wide survey for molecular mimicry proteins in parasites. The strategy can be adopted to any pair of host and pathogen, once appropriate negative control organisms are chosen. MimicDB provides a host of new starting points to gain insights into the molecular nature of host-pathogen interactions.

  16. Genome-Wide Identification of Molecular Mimicry Candidates in Parasites

    PubMed Central

    Ludin, Philipp; Nilsson, Daniel; Mäser, Pascal

    2011-01-01

    Among the many strategies employed by parasites for immune evasion and host manipulation, one of the most fascinating is molecular mimicry. With genome sequences available for host and parasite, mimicry of linear amino acid epitopes can be investigated by comparative genomics. Here we developed an in silico pipeline for genome-wide identification of molecular mimicry candidate proteins or epitopes. The predicted proteome of a given parasite was broken down into overlapping fragments, each of which was screened for close hits in the human proteome. Control searches were carried out against unrelated, free-living eukaryotes to eliminate the generally conserved proteins, and with randomized versions of the parasite proteins to get an estimate of statistical significance. This simple but computation-intensive approach yielded interesting candidates from human-pathogenic parasites. From Plasmodium falciparum, it returned a 14 amino acid motif in several of the PfEMP1 variants identical to part of the heparin-binding domain in the immunosuppressive serum protein vitronectin. And in Brugia malayi, fragments were detected that matched to periphilin-1, a protein of cell-cell junctions involved in barrier formation. All the results are publicly available by means of mimicDB, a searchable online database for molecular mimicry candidates from pathogens. To our knowledge, this is the first genome-wide survey for molecular mimicry proteins in parasites. The strategy can be adopted to any pair of host and pathogen, once appropriate negative control organisms are chosen. MimicDB provides a host of new starting points to gain insights into the molecular nature of host-pathogen interactions. PMID:21408160

  17. Do invasive cane toads affect the parasite burdens of native Australian frogs?☆

    PubMed Central

    Lettoof, Damian C.; Greenlees, Matthew J.; Stockwell, Michelle; Shine, Richard

    2013-01-01

    One of the most devastating impacts of an invasive species is the introduction of novel parasites or diseases to native fauna. Invasive cane toads (Rhinella marina) in Australia contain several types of parasites, raising concern that the toads may increase rates of parasitism in local anuran species. We sampled cane toads and sympatric native frogs (Limnodynastes peronii, Litoria latopalmata, and Litoria nasuta) at the southern invasion front of cane toads in north-eastern New South Wales (NSW). We dissected and swabbed these anurans to score the presence and abundance of nematodes (Rhabdias lungworms, and gastric encysting nematodes), myxozoans, and chytrid fungus. To determine if cane toad invasion influences rates of parasitism in native frogs, we compared the prevalence and intensity of parasites in frogs from areas with toads, to frogs from areas without toads. Contrary to the situation on the (rapidly-expanding) tropical invasion front, cane toads on the slowly-expanding southern front were heavily infected with rhabditoid lungworms. Toads also contained gastric-encysting nematodes, and one toad was infected by chytrid fungus, but we did not find myxozoans in any toads. All parasite groups were recorded in native frogs, but were less common in areas invaded by toads than in nearby yet to be invaded areas. Contrary to our predictions, toad invasion was associated with a reduced parasite burden in native frogs. Thus, cane toads do not appear to transfer novel parasites to native frog populations, or act as a reservoir for native parasites to ‘spill-back’ into native frogs. Instead, cane toads may reduce frog-parasite numbers by taking up native parasites that are then killed by the toad’s immune defences. PMID:24533330

  18. The role of host sex in parasite dynamics: individual based model simulations of host-parasite interactions in a semi-enclosed embayment.

    NASA Astrophysics Data System (ADS)

    Velo Suarez, L.; Arancio, M.; Sourisseau, M.

    2016-02-01

    Parasitic dinoflagellates of the genus Amoebophrya infect free-living dinoflagellates, some of which can cause harmful algal blooms (HABs). During a field study in Salt Pond (MA, USA), we found a significant influence of Amoebophrya spp. on populations of Alexandrium fundyense. Parasitism appeared to exhibit a significant top down influence on A. fundyense populations and a dramatic life-cycle transition from vegetative division to sexual fusion was recorded. Despite our intensive sampling in Salt Pond, host-parasite interactions were undersampled owing to the very short time scales relevant to host-Amoebophrya spp. dynamics. In the present work, we explored the role of sexual reproduction and excystment/encystment processes using an Individual Based Model (IBM). The model was parameterized using published data and laboratory experiments carried out to analyze Amoebophrya spp. functional response. Observed-simulated differences in host-parasite dynamics support the hypothesis of parasite-host simultaneous dormancy, and further excystment months later to propagate both species. Results suggest that coexistence of A. fundyense and Amoebophrya spp. and their annual persistence in Salt Pond might rely on a sexual response/encystment. Understanding host-parasite interactions and coexistence strategies will improve our knowledge of Alexandrium spp. blooms and assess the impact of parasites on natural plankton assemblages in coastal systems.

  19. Parasitic community of Fransciscodoras marmoratus (Reinhardt, 1874) (Pisces: Siluriformes, Doradidae) from the upper São Francisco River, Brazil.

    PubMed

    Santos, M D; Brasil-Sato, M C

    2006-08-01

    One hundred and thirteen specimens of Franciscodoras marmoratus (Reinhardt, 1874) were collected in the upper São Francisco River (18 degrees 12' 32" S, 45 degrees 15' 41" W, state of Minas Gerais) between September, 1999 and January, 2004 to investigate their parasite fauna. From this total, 45 (39.8%) were afflicted by at least one parasite species. The parasitic richness consisted of six species represented by Hirudinea (n = 20), Monogenoidea (n = 25), Eucestoda (n = 55), Nematoda (n = 1, n = 2) and Acanthocephala (n = 41) found in the dry and wet periods making a total of 144 specimens. Proteocephalus renaudi Chambrier & Vaucher, 1994 was the only species with prevalence higher than 10% and a typical aggregate distribution pattern. The prevalence, intensity and abundance of P. renaudi were not influenced by the total length or sex of the hosts or by the collection periods. The relative condition factor indicated that the health of the P. renaudi hosts was not significantly affected in relation to fish not infected by parasites. The fish stocked in tanks before necropsy were opportunistically infested by Lernaea cyprinacea Yashuv, 1959. The various parasites found indicate that F. marmoratus is omnivorous and a potential definitive host. The parasite species, except for Acanthocephala, have expanded their known geographic distribution to the São Francisco River Basin. The parasite community was considered isolationist because of the low endoparasite diversity, infrapopulations with low intensity, lack of evidence of parasite interactions and sparse signs of parasite aggression against their hosts.

  20. Are Sick Individuals Weak Competitors? Competitive Ability of Snails Parasitized by a Gigantism-Inducing Trematode

    PubMed Central

    Seppälä, Otto; Karvonen, Anssi; Kuosa, Marja; Haataja, Maarit; Jokela, Jukka

    2013-01-01

    Parasitized individuals are often expected to be poor competitors because they are weakened by infections. Many trematode species, however, although extensively exploiting their mollusc hosts, also induce gigantism (increased host size) by diverting host resources towards growth instead of reproduction. In such systems, alternatively to reduced competitive ability due to negative effects of parasitism on host performance, larger size could allow more efficient resource acquisition and thus increase the relative competitive ability of host individuals. We addressed this hypothesis by testing the effect of a trematode parasite Diplostomum pseudospathaceum on the competitive ability of its snail host Lymnaea stagnalis. We experimentally examined the growth of snails kept in pairs in relation to their infection status and intensity of resource competition (i.e. food availability). We found that parasitized snails grew faster and their reproduction was reduced compared to unparasitized individuals indicating parasite-induced gigantism. However, growth of the snails was faster when competing with parasitized individuals compared to unparasitized snails indicating reduced competitive ability due to parasitism. The latter effect, however, was relatively weak suggesting that the effects of the parasite on snail physiology may partly override each other in determining competitive ability. PMID:24205383

  1. Genetic variation in resistance, but not tolerance, to a protozoan parasite in the monarch butterfly

    PubMed Central

    Lefèvre, Thierry; Williams, Amanda Jo; de Roode, Jacobus C.

    2011-01-01

    Natural selection should strongly favour hosts that can protect themselves against parasites. Most studies on animals so far have focused on resistance, a series of mechanisms through which hosts prevent infection, reduce parasite growth or clear infection. However, animals may instead evolve tolerance, a defence mechanism by which hosts do not reduce parasite infection or growth, but instead alleviate the negative fitness consequences of such infection and growth. Here, we studied genetic variation in resistance and tolerance in the monarch butterfly (Danaus plexippus) to its naturally occurring protozoan parasite, Ophryocystis elektroscirrha. We exposed 560 monarch larvae of 19 different family lines to one of five different parasite inoculation doses (0, 1, 5, 10 and 100 infective spores) to create a range of parasite loads in infected butterflies. We then used two proxies of host fitness (adult lifespan and body mass) to quantify: (i) qualitative resistance (the ability to prevent infection; also known as avoidance or anti-infection resistance); (ii) quantitative resistance (the ability to limit parasite growth upon infection; also known as control or anti-growth resistance); and (iii) tolerance (the ability to maintain fitness with increasing parasite infection intensity). We found significant differences among host families in qualitative and quantitative resistance, indicating genetic variation in resistance. However, we found no genetic variation in tolerance. This may indicate that all butterflies in our studied population have evolved maximum tolerance, as predicted by some theoretical models. PMID:20843849

  2. Parasites of pigs in two farms with poor husbandry practices in Bishoftu, Ethiopia.

    PubMed

    Jufare, Alemnesh; Awol, Nesibu; Tadesse, Fanos; Tsegaye, Yisehak; Hadush, Birhanu

    2015-04-30

    A cross-sectional study was conducted from November 2011 to April 2012 on a total of 384 pigs from two privately owned intensive farms in Bishoftu, Ethiopia. The objectives of the study were to identify and determine the prevalence of common parasites of pigs. For the determination of gastrointestinal (GIT) parasites, faecal samples were collected from the study animals and subjected to standard parasitological examination techniques. Physical examination was conducted for the presence of skin parasitic lesions and skin scrapings were collected to determine prevalence of ectoparasites. The overall prevalence of GIT parasites in the pigs was 25% (96/384). Examination of faecal samples revealed the ova or oocysts of four different gastrointestinal parasites, namely Coccidia (12%), Strongyles (5.2%), Ascaris suum (4.9%) and Trichuris suis (2.9%). Mixed infection by at least two parasite species was observed in 3.65% (14/384) of the pigs. The only ectoparasite species identified was Sarcoptes scabiei var. suis, with a prevalence of 2.6%. This study indicates that pig parasites are a major problem in the study area, hence implementation of strategic control measures and appropriate hygienic management systems are recommended to reduce the prevalence of parasites.

  3. Larval size in acanthocephalan parasites: Influence of intraspecific competition and effects on intermediate host behavioural changes

    PubMed Central

    2012-01-01

    Background Parasites often face a trade-off between exploitation of host resources and transmission probabilities to the next host. In helminths, larval growth, a major component of adult parasite fitness, is linked to exploitation of intermediate host resources and is influenced by the presence of co-infecting conspecifics. In manipulative parasites, larval growth strategy could also interact with their ability to alter intermediate host phenotype and influence parasite transmission. Methods We used experimental infections of Gammarus pulex by Pomphorhynchus laevis (Acanthocephala), to investigate larval size effects on host behavioural manipulation among different parasite sibships and various degrees of intra-host competition. Results Intra-host competition reduced mean P. laevis cystacanth size, but the largest cystacanth within a host always reached the same size. Therefore, all co-infecting parasites did not equally suffer from intraspecific competition. Under no intra-host competition (1 parasite per host), larval size was positively correlated with host phototaxis. At higher infection intensities, this relationship disappeared, possibly because of strong competition for host resources, and thus larval growth, and limited manipulative abilities of co-infecting larval acanthocephalans. Conclusions Our study indicates that behavioural manipulation is a condition-dependant phenomenon that needs the integration of parasite-related variables to be fully understood. PMID:22876882

  4. Genetic variation in resistance, but not tolerance, to a protozoan parasite in the monarch butterfly.

    PubMed

    Lefèvre, Thierry; Williams, Amanda Jo; de Roode, Jacobus C

    2011-03-07

    Natural selection should strongly favour hosts that can protect themselves against parasites. Most studies on animals so far have focused on resistance, a series of mechanisms through which hosts prevent infection, reduce parasite growth or clear infection. However, animals may instead evolve tolerance, a defence mechanism by which hosts do not reduce parasite infection or growth, but instead alleviate the negative fitness consequences of such infection and growth. Here, we studied genetic variation in resistance and tolerance in the monarch butterfly (Danaus plexippus) to its naturally occurring protozoan parasite, Ophryocystis elektroscirrha. We exposed 560 monarch larvae of 19 different family lines to one of five different parasite inoculation doses (0, 1, 5, 10 and 100 infective spores) to create a range of parasite loads in infected butterflies. We then used two proxies of host fitness (adult lifespan and body mass) to quantify: (i) qualitative resistance (the ability to prevent infection; also known as avoidance or anti-infection resistance); (ii) quantitative resistance (the ability to limit parasite growth upon infection; also known as control or anti-growth resistance); and (iii) tolerance (the ability to maintain fitness with increasing parasite infection intensity). We found significant differences among host families in qualitative and quantitative resistance, indicating genetic variation in resistance. However, we found no genetic variation in tolerance. This may indicate that all butterflies in our studied population have evolved maximum tolerance, as predicted by some theoretical models.

  5. Helminths infection patterns in a lizard (Tropidurus hispidus) population from a semiarid neotropical area: associations between female reproductive allocation and parasite loads.

    PubMed

    Galdino, Conrado A B; Ávila, Robson W; Bezerra, Castiele H; Passos, Daniel C; Melo, Gabriela C; Zanchi-Silva, Djan

    2014-12-01

    This study reports helminth infection patterns of the lizard Tropidurus hispidus from an area of semiarid caatinga in northeastern Brazil (Ceará state). The lizard population was parasitized by 8 helminth species, and the species composition of the component community resembles that found for other Neotropical lizards. The prevalence of parasites was higher for males compared with females, whereas no relation was found between intensity of infection of 2 parasites (Parapharyngodon alvarengai and Physaloptera lutzi) and the lizards body size. For reproductive females, parasite infection intensity was negatively correlated to reproductive investment.

  6. Parasites of juvenile golden grey mullet Liza aurata Risso, 1810 in Sarıkum Lagoon Lake at Sinop, Turkey.

    PubMed

    Öztürk, Türkay

    2013-12-01

    Juvenile golden grey mullet, Liza aurata were collected from Sarıkum Lagoon Lake which connected to the Black Sea at Sinop, Turkey and examined for parasitic fauna. A total of 219 fish were investigated throughout a 1-year period. Parasite species recovered were Trichodina lepsii, T. puytoraci, Gyrodactylus sp., Ligophorus cephali, Ligophorus mediterraneus, Solostamenides mugilis, Ascocotyle sp. (metacercaria) and Ergasilus lizae. Overall infection prevalence (%) and mean intensity values were 95.9% and 412.65 ± 85.31 parasites per infected fish, respectively. Infection prevalence and mean intensity values for each parasite species in relation to season and fish size were also determined and discussed. While Ligophorus cephali and L. mediterraneus are new records for Turkish parasite fauna, the juvenile Liza aurata is a new host record for Ligophorus cephali and L. mediterraneus.

  7. Associations of Forest Type, Parasitism and Body Condition of Two European Passerines, Fringilla coelebs and Sylvia atricapilla

    PubMed Central

    Lüdtke, Bruntje; Moser, Isabelle; Santiago-Alarcon, Diego; Fischer, Markus; Kalko, Elisabeth KV.; Schaefer, H. Martin; Suarez-Rubio, Marcela; Tschapka, Marco; Renner, Swen C.

    2013-01-01

    Human-induced forest modification can alter parasite-host interactions and might change the persistence of host populations. We captured individuals of two widespread European passerines (Fringilla coelebs and Sylvia atricapilla) in southwestern Germany to disentangle the associations of forest types and parasitism by haemosporidian parasites on the body condition of birds. We compared parasite prevalence and parasite