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The importance of parasites as a selective force in host evolution is a topic of current interest. However, short-term ecological studies of host–parasite systems, on which such studies are usually based, provide only snap-shots of what may be dynamic systems. We report here on four surveys, carried out over a period of 12 years, of helminths of spiny mice (Acomys dimidiatus), the numerically dominant rodents inhabiting dry montane wadis in the Sinai Peninsula. With host age (age-dependent effects on prevalence and abundance were prominent) and sex (female bias in abundance in helminth diversity and in several taxa including Cestoda) taken into consideration, we focus on the relative importance of temporal and spatial effects on helminth infracommunities. We show that site of capture is the major determinant of prevalence and abundance of species (and higher taxa) contributing to helminth community structure, the only exceptions beingStreptopharausspp. andDentostomella kuntzi.We provide evidence that most (notably the Spiruroidea,Protospirura muricola,Mastophorus murisandGongylonema aegypti, but with exceptions among the Oxyuroidae, e.g.Syphacia minuta), show elements of temporal-site stability, with a rank order of measures among sites remaining similar over successive surveys. Hence, there are some elements of predictability in these systems.

Although synanthropic rodents such as the indigenous species, Mastomys coucha, and the invasive species, Rattus norvegicus, R. rattus and R. tanezumi, are well-known to be hosts to various micro- and macroparasites, their helminth parasite fauna is poorly studied in South Africa. In an attempt to remedy the situation, the aim of the present study was to investigate the helminth fauna of these sympatric rodent species, which were obtained from the informal settlements of Alexandra, Tembisa, Diepsloot and residential suburbs of Pretoria and Hammanskraal, Gauteng Province, South Africa. Helminths were recovered from the urinary bladder, liver and gastrointestinal tract and were identified morphologically and molecularly. The recovered nematodes were all rodent-specific and included Aspiculuris tetraptera, Eucoleus sp., Heterakis spumosa, Mastophorus muris, Nippostrongylus brasiliensis, Protospirura sp., Strongyloides ratti, Syphacia obvelata, Syphacia muris, Trichuris sp. and Trichosomoides crassicauda. Syphacia obvelata, a commensal nematode of laboratory rodents, was recovered from indigenous M. coucha. Strobilar stages of cestodes recovered included Hymenolepis diminuta, Hymenolepis nana and Inermicapsifer madagascariensis. Recovered metacestodes were strobilocerci of Hydatigera taeniaeformis from all three invasive Rattus species and coenurostrobilocerci of Hydatigera parva from M. coucha. An acanthocephalan, Moniliformis moniliformis, was recovered from R. rattus only. All rodent species examined showed high helminth infection prevalence (≥70%) with equal or higher nematode than cestode prevalence. Mastomys coucha, however, showed significantly lower cestode prevalence than Rattus species where they co-occur. Interspecific transmission of helminths likely occurs between invasive and indigenous rodents, and these rodents harbour several helminths that have zoonotic implications.

Summary The aim of this study was to determine the prevalence and species composition of helminths in commensal rodents captured inside private residences in the city of Villahermosa in Tabasco, Mexico. Trapping was performed at each house for three consecutive nights from October to December 2015. Fifty commensal rodents were captured: 23 Rattus norvegicus, 16 Mus musculus and 11 Rattus rattus. Rodents were transported alive to the laboratory and held in cages until they defecated. Feces were analyzed for helminth eggs using the Sheather’s flotation technique. The overall prevalence of helminths in rodents was 60 %: R. norvegicus was more likely to be parasitized (87.0 %) than R. rattus (63.6 %) and M. musculus (18.8 %). Eggs from at least 13 species of helminths were identified: Hymenolepis diminuta, Rodentolepis nana, Moniliformis moniliformis, Heligmosomoides polygyrus, Heterakis spumosa, Mastophorus muris, Nippostrongylus brasiliensis, Strongyloides ratti, Syphacia obvelata, Syphacia muris, Toxocara sp., Trichosomoides crassicauda, and Trichuris muris. This is the first study to report the presence of H. polygyrus, S. ratti and T. crassicauda in commensal rodents in Mexico. In conclusion, our results suggest that helminths commonly infect commensal rodents in Villahermosa and therefore rodents present a health risk to inhabitants in this region.

This study focused on the spirurid nematodeMastophorus murisin water voles (Arvicola amphibius) trapped in three regions in southern Sweden during spring and fall 2013. The collection of water voles formed part of a larger project (EMIRO) on the cestodeEchinococcus multilocularisin rodents. The voles’ stomach contents were examined for the presence ofM. muris. Prevalence, mean abundance and mean intensity of infection were calculated. A generalized linear model model was used to examine the effects of sex, functional group, season and region on the number ofM. murisindividuals in each vole. Forty-seven of 181 (26%) voles were infected withM. muris, with up to 74 worms each. The overall mean intensity (worms per infected vole) was 15 (95% CI 10–21), and abundance (mean number of worms in all voles) was 4 (95% CI 2–6). Model output indicated a significant effect of season and region with respect to abundance of nematode infection, which was independent of sex and functional group of the investigated host.

SUMMARYParasites are considered to be an important selective force in host evolution but ecological studies of host-parasite systems are usually short-term providing only snap-shots of what may be dynamic systems. We have conducted four surveys of helminths of bank voles at three ecologically similar woodland sites in NE Poland, spaced over a period of 11 years, to assess the relative importance of temporal and spatial effects on helminth infracommunities. Some measures of infracommunity structure maintained relative stability: the rank order of prevalence and abundance ofHeligmosomum mixtum, Heligmosomoides glareoliandMastophorus murischanged little between the four surveys. Other measures changed markedly: dynamic changes were evident inSyphacia petrusewicziwhich declined to local extinction, while the capillariidAonchotheca annulosafirst appeared in 2002 and then increased in prevalence and abundance over the remaining three surveys. Some species are therefore dynamic and both introductions and extinctions can be expected in ecological time. At higher taxonomic levels and for derived measures, year and host-age effects and their interactions with site are important. Our surveys emphasize that the site of capture is the major determinant of the species contributing to helminth community structure, providing some predictability in these systems.

Some small mammals occur as household pests and harbour a number of parasites that could be of public health importance. This study profiled the helminth and protozoan parasites in trapped small mammals within and around human dwelling places (houses) located across 4 major towns (Auchi, Benin, Ekpoma, and Uromi) and environs in Edo state, Nigeria. Six genera (Apodemus sp., Crocidura sp., Mastomys natalensis, Mus musculus, Rattus sp., and Sorex sp.) were identified from 502 trapped small mammals. Overall, M. musculus (71.9%) and Rattus rattus (20.1%) were the most frequently trapped. In total, on examination of blood, gastrointestinal contents, and brain tissues, 12 helminth taxa (Angiostrongylus sp., Aspicularis sp., Capillaria sp., Gongylonema sp., Heterakis spumosa, Hymenolepis diminuta, Hymenolepis nana, Mastophorus muris, Moniliformis moniliformis, Nippostrongylus brasiliensis, Strongyloides sp., Trichosomoides sp., and Trichuris sp.), and 6 protozoan parasites (Babesia sp., Trypanosoma lewisi, Plasmodium sp., Eimeria sp., Isospora sp., and Toxoplasma gondii) were isolated. Most prevalent helminths with relatively heavy mean intensity were Strongyloides sp. and Heterakis spumosa, while Plasmodium, Eimeria, and Isospora were the most prevalent protozoan parasites. Generally, intrinsic factors like sex and age had marginal influence on the rate and burden of infection in M. musculus and R. rattus. Although the infection rate and prevalence of zoonotic parasites were low, they were largely recovered in rodents from Ekpoma. This study elucidates the public health implication of the presence of zoonotic parasites in these small mammals.

The gastrointestinal parasites and their prevalence of infections in root voles, Microtus oeconomus Pallas, were studied in the Haibei area, Qinghai Province, China. Feces were collected from 196 voles for analysis of intestinal coccidia; 37/196 (19%) were infected with Eimeria wenrichi, 8/196 (8%) with Eimeria ochrogasteri, 2/196 (1%) with Eimeria saxei, and 1/196 (0.5%) with Isposora mexicanasubsimi. We necropsied 67 voles and found 5 helminth species representing 1 nematode and 4 cestodes species; these were the spirurid nematode Mastophorus muris in 9/67 (13%), the cestodes Paranoplocephala macrocephala in 3/67 (4%) P. omphalodes in 2/67 (3%), Anoplocephaloides dentate in 1/67 (1.5%), and the cestode larval stage Cysticercus fasciolaris in 3/67 (4.5%). We provide photomicrographs to illustrate these gastrointestinal parasites from M. oeconomus in China for the first time; the 4 intestinal eimerians represent new locality records.

Fifty-one specimens of small mammals were collected from different locations of Kerman province, southeastern Iran during 2007 and 2009. They constitute six species of rodents (Meriones persicus, Meriones libycus, Tatera indica, Dryomys nitedula and Mus musculus), one species of Erinaceomorpha (Paraechinus hypomelas) and one species of hare (Lepus europeus). The rate of helminthic infection was 45.1 % among all trapped specimens. In 28 out of 51 hunted specimens no intestinal helminth parasite was found. Of all mammals examined, 15 (29.4 %) had nematodes, 5 (9.8 %) had cestodes, and 3 (5.9 %) were infected with Acanthocephala. Five different species of parasites were isolated: Trichuris muris, Moniliformis moniliformis, Hymenolepis diminuta, Hymenolepis nana, and Mastophorus muris. Results of the present study indicate the potential of small mammals in the transmission of zoonotic helminthic infection.

This paper reports the role of darkling beetles Pimelia laevigata costipennis and Hegeter amaroides (Tenebrionidae) as intermediate hosts of spiruroid nematodes parasites of the black rat and house mouse of El Hierro (Canary Islands). Larvae of spiruroid species were found in the two tenebrionids (18.1% in P. l. costipennis, 7.8% in H. amaroides), Streptopharagus greenbergi being predominant in both (16.1% and 7.1%, respectively), ahead of Mastophorus muris and Gongylonema type larva. The larval stages of S. greenbergi are described for the first time, and adult worms were obtained experimentally from an infected laboratory rat, allowing the identification of the species. Morphometric measurements of experimental adults match those of adults detected in naturally infected rats on the island. Molecular data for S. greenbergi, and the ITS nucleotide sequence of the genus Streptopharagus are also provided for the first time. After the isolation of S. greenbergi DNA and amplification of the ITS region, the ITS1 of this spirocercid was sequenced and deposited in the GenBank database.

A lack of newly acquired species partly explains why introduced host species have poor specific parasite diversity. The intestinal helminth community from two native Murid host species, wood mice Apodemus sylvaticus [Murinae] (n = 40), bank voles Clethrionomys glareolus [Arvicolinae] (n = 42), and an introduced Sciurid, the Siberian chipmunk Tamias sibiricus (n = 42), dominant in the rodent communities, was studied from three woody areas in the Ile-de-France region. Native gastrointestinal helminth fauna from mice and voles was formed by 12 taxa: ten nematodes, Aonchotheca murissylvatici, Aonchotheca annulosa, Aspiculuris tetraptera, Eucoleus sp., Heligmosomoides glareoli, Heligmosomoides polygyrus, Mastophorus muris, Syphacia frederici, Syphacia stroma, Trichuris muris, a Cestode and a Trematode. Two helminth taxa were imported by chipmunks from eastern Asia: Brevistriata skrjabini and Strongyloides callosciureus. Only A. annulosa was transferred to chipmunks from the native small rodent community. None of the 82 native murids harbored chipmunk helminths. The developmental ability of helminth according to host phylogenetic relatedness was the main driving force explaining the species composition of the helminth community between these sympatric native and introduced hosts.

The helminth fauna of the house mouse (Mus musculus Linnaeus, 1758) was studied on the basis of 429 host individuals from the suburban area of Belgrade. Eleven helminth species were recorded: three cestode species - Catenotaenia pusilla, Rodentolepis fraterna, and Cysticercus (= Strobilocercus) fasciolaris [larval stage of Taenia taeniaeformis (Batsch, 1821)]; and eight nematode species - Heligmosomoides polygyrus, Syphacia sp., Aspiculuris tetraptera, Syphacia obvelata, Heterakis spumosa, Trichuris muris, Mastophorus muris, and Gongylonema sp. Within the general helminth fauna, H. polygyrus was found to be the most prevalent species (39.2%) and caused the highest infection intensity. Prevalences of A. tetraptera, C. pusilla, and S. obvelata ranged from 12.8% to 6.1%, while the remaining species showed prevalences ranging from 4.9% (for Syphacia sp.) to 0.2% (for Gongylonema sp.). All the species found in males were also present in females, with the exceptions of M. muris and Gongylonema sp. No significant differences were found between males and females regarding prevalence (P%), mean infection intensity (MI), or mean abundance (MA).

Master in applied ecology. Evenstad 2015 I studied the spirurian nematode (Mastophorus muris) in water voles (Arvicola amphibius) in southern Sweden. Limited information is known about this nematode particularly in water voles. Trapping was done using topcats in the spring and fall of 2013 in three regions of Sweden: Uddevalla, Katrineholm and Gnesta/Nyköping. Rodents were frozen and stomach content and feces were examined after thawing for presence of M. muris. Prevalence, mean abundance and mean intensity of infection of M. muris were calculated. A GLM model was used to examine the effect of sex, functional group, season, and region on the numbers of M. muris and presence or absence of M. muris in each vole. Forty-seven of 181 (26%) voles were infected with M. muris. Infected voles had up to 74 worms. The overall mean intensity [worms per infected vole, 95% CI] was 15, 10-21 and mean abundance [average numbers of worms in all voles, 95% CI] was 4, 2-6. Mean abundance was also calculated for sex [females 5, 2-7; males 3, 1-6], functional group [adults 5, 2-9; subadults/juveniles 4, 1-6; unknown 3, -1-8], season [spring 7, 3-12; fall 3, 1-5], and region [Gnesta/Nyköping 6, 1-11; Uddevalla 4, 1-6; Katrineholm 4, 1-6]. Model output indicated a significant effect of season (p

This study provides the first data on the helminth fauna of the Eurasian badger in the southwestern edge of its range (Grândola Mountain, Portugal) and interprets the results in relation to badger diet and feeding behaviour. By examination of 163 badger faecal samples, faecal developmental stages (eliminative forms) of four helminth species and one genus were identified: one cestode (Atriotaenia incisa) and four nematodes (Mastophorus muris, Molineus patens, Uncinaria criniformis and Strongyloides sp.). The overall prevalence of parasites was 62%, with limited seasonal variation. Single parasite excretions were dominant and Strongyloides sp. excretion was the most common. Diet assessment based on 450 faecal samples revealed that badgers consumed mainly insects and fruits. No correlation was detected between helminth prevalence and diet. Apparently, diet (mainly insects) and feeding behaviour (fossorial), together with the species’ social behaviour (anal scent marking of group members), facilitate the infection with helminths. The helminth fauna of Eurasian badgers in Grândola Mountain has isolationist characteristics, apparently indicating low host colonisation.

Mastophorus muris (Gmelin, 1790) (Nemotada: spiruroidea) a ete retrouve chez Graomys griseoflavus (Walerbouse, 1837) (Rodentia: Sigmoolontinae) dans la province de La Pampa, Argentine. La validite de Mastophorus (Spirocercidae: Mastophorinae), parfois encore confondu avec Protospirura (Spiruridae), est une nouvelle fois confirmee. La disposition des dents pseudolabiales (petites dents situees de part et d'autre d'une gronde dent centrale), qui semble etre assez constante dans toutes les descriptions connues de l'espece, est confirmee a l'aide du microscope electronique a balayage. Il s'agit de la premiere mention de l'espece en Argentine, et de plus chez un hote sauvage en Amerique du Sud. Ceci met en evidence l'expansion de l'espece qui, jusqu'a present, n'etait connue que chez des rongeurs domestiques dans le sous-continent.

Six house mice (Mus musculus), seven yellow-necked mice (Apodemus flavicollis), 10 striped field mice (A. agrarius), five muskrats (Ondatra zibethicus), one water vole (Arvicola terrestris), 126 bank voles (Clethrionomys glareolus), 12 short-tailed voles (Microtus agrestis), and two European beavers (Castor fiber) were examined for helminths. Data are presented about infection of the rodents with trematodes, nematodes, and larvae of cestodes. Twenty three helminth species were found. In Lithuania, Echinococcus multilocularis was found in rodents for the first time. Three helminths were found in new hosts in Lithuania: Plagiorchis elegans – in the bank vole, Mastophorus muris – in the house mouse, and Tetratirotaenia polyacantha – in the muskrat. In the European beaver, only Stichorchis subtriquetrus and Travassosius rufus, helminths specific to this species, were detected. The helminth fauna in the muskrat and the water vole was formed of helminths hosted by a wide range of waterfowl and mammals.

Helminth parasites were studied in the bank vole, Clethrionomys glareolus, (Rodentia, Arvicolinae), in southern Italy (Calabrian region). In total, 193 C. glareolus from three different areas captured between 1982 and 2001 were examined and nine species of helminths were recovered: one trematode (Corrigia vitta), four cestodes (Taenia martis larvae, Mesocestoides sp. larvae, Paranoplocephala omphalodes, Catenotaenia henttoneni) and four nematodes (Aonchotheca annulosa, Mastophorus muris, He‐ligmosomoides glareoli, Syphacia petrusewiczi). This is the first record of the bank vole helminth fauna in Italy. The study of the helminth community of this host reveals no quantitative differences between sexes and habitat influences, but the data show an isolationist character of the community due to low diversity and reduced interactions between species. The geographic localization of Calabria, the limit of the range of this species in Europe, could affect the low species richness found in C. glareolus in...

Abundance and prevalence of helminth infections often differ between host sexes, and are usually biased in favor of males. Relatively few cases of female-biased parasitism have been reported. We sampled bank voles in three woodland sites in N.E. Poland over 11 years at 3-4-year intervals, and assessed their parasite burdens. Prevalence and abundance of the stomach nematode Mastophorus muris were consistently higher among females. Among adult female bank voles from the two sites that showed the highest prevalence with M. muris, both prevalence and abundance were significantly higher in lactating bank voles, but not pregnant animals, and the effect of lactation was evident in both sites, in all four surveys, and in both age classes. Although the magnitude of the effect of lactation varied between years, it was not confounded by any significant interactions with other factors. We hypothesize that mature and reproductively active female bank voles are subject to higher exposure compared with males of similar age, as a consequence of the increased content of invertebrates in their diet, including the intermediate hosts of M. muris, required to meet the higher increased energy and protein demands of nursing litters throughout the summer months.

Urban brown rats (Rattus norvegicus) carry microbial human pathogens but their role as reservoir hosts for helminths of public health importance is less well known. In this study, 42 brown rats trapped on Merseyside were subject to thorough combined helminthological and pathohistological post-mortem examination. Eggs of the rodent-borne zoonotic nematode Calodium hepaticum were initially detected in histological sections of the livers of 9.5% of rats, but overall diagnostic sensitivity increased to 16.6% when entire liver tissue was disrupted and the resulting filtrates were examined for released eggs. In their rat host, mainly trapped inside the dockland, infections with C. hepaticum were associated with a chronic multifocal pyogranulomatous hepatitis with intralesional eggs and peripheral fibrosis. Mean intensity of hepatic C. hepaticum egg infections was 1041 eggs. This is the first report of C. hepaticum in an urban brown rat population in the UK and provides original data for liver egg burdens in this abundant commensal rodent. The zoonotic cestode Rodentolepis nana had a prevalence of infection of 14.3%. Rodent-specific, non-zoonotic helminths found were the spiruroid Mastophorus muris (16.0%) in the stomach, the trichuroid Trichosomoides crassicauda in the urinary bladder (31.0%); the ascarid Heterakis spumosa was the commonest helminth of the large intestine (76.2%). Many millions of brown rats inhabit cities and rural areas of the UK, and the infective stages of the zoonotic worm species, particularly C. hepaticum, are likely to be widely distributed in the environment presenting a threat to public health.

A helminthological survey was performed on 143 brown rats (Rattus norvegicus) from the city of Palermo (Italy). The overall prevalence of helminth infection was 98.60 %. The following parasites were found: Brachylaima sp. (prevalence 8.39 %) (Trematoda); Taenia taeniaeformis larvae (11.89 %), Rodentolepis nana (13.29 %), Hymenolepis diminuta (24.48 %) (Cestoda); Gongylonema sp., (4.90 %), Syphacia muris (8.39 %), Nippostrongylus brasiliensis (18.88 %), Eucoleus gastricus (30.07 %), Mastophorus muris (30.77 %), Capillaria hepatica (54.55 %), Heterakis spumosa (82.52 %) (Nematoda) and one acanthocephalan (0.70 %). The species found in males were also present in females, with the exception of the acanthocephalan. No significant differences were found between males and females in prevalence (P%) or mean infection intensity (MI). However, a significant correlation between both P% and MI, as well as host age, was observed in some helminth species. Hosts were infected by one to six helminth species (median = 3). This is the first report from Sicily of helminths in R. norvegicus.

Le caryotype de Mastophorus muris (Gmelin, 1790) comprend quatre paires de courts chromosomes autosaumaux et deux chromosomes X chez la femelle, ou un X chez le mâle (2n = 8 + XX/XO). Toutes le paires de chromosomes possedent a peu pres la meme morphologie, sans constriction primaire ou secondaire. L'analyse par C-banding n'a pas permis de reveler la presence de bande d'heterochromatine. La longueur totale du chromosome est comprise entre 4,02 et 2,24 μm. La plus grande longueur totale du chromosome haploide est de 14,34 μm Le cycle de la gametogenese represente un modele commun dans l'ordre des Spirurida. Le caryotype d'autres spirurid nematodes a ete revu.

Spiny mice,Acomys cahirinus dimidiatus, inhabiting the wadis close to St Katherine in the mountains of the Sinai peninsula, were trapped and their helminth parasites were studied. Sixty one mice provided faeces for analysis and 27 were killed and autopsied. Six species of helminths were recorded (the spirurid nematodes,Protospirura muricola(74.1%) andMastophorus muris(11.1%), the oxyuroid nematodes,Dentostomella kuntzi(59.3%),Aspiculuris africana(3.7%), andSyphacia minuta(3.7%) and the hymenolepidid cestodeRodentolepis negevi(18.5%)). The spirurids were the dominant species present, accounting for up to 0.87% of total host body weight. Analysis of worm weights and lengths suggested that transmission had been taking place in the months preceding our study. No sex difference in the prevalence or abundance of spirurids was detected. Significant differences were identified in the abundance of total nematode burdens and the mean helminth species richness between the three wadis which provided multiple captures of mice. There was also a marked effect of host age on both parameters. A highly significant positive correlation between spirurid egg counts and total worm biomass indicated that non-invasive techniques based on egg counts could be used to quantify worm burdens and when this technique was applied to a larger sample size (n= 61), a significant difference between sites but no host sex or age effects were detected for spirurid faecal egg counts. The data suggest that there are differences between helminth component communities infecting spiny mice in different neighbouring wadis, a hypothesis which will be explored further through our continuing studies in the Sinai.

Specimens of 12 helminth species were collected from carcasses of eight Lynx pardinus (Temminck, 1827), a carnivore endemic to the Iberian Peninsula. These species included: Brachylaima sp. (12.5%) (Trematoda); Taenia pisiformis (12.5%), T. polyacantha (25%), T. taeniaeformis (25%) and Mesocestoides litteratus (37.5%) (Cestoda); Eucoleus aerophilus (12.5%), Ancylostoma tubaeforme (12.5%), Toxocara cati (37.5%), Toxascaris leonina (62.5%), Vigisospirura potekhina potekhina (12.5%), Mastophorus muris (12.5%) and Physaloptera praeputialis (12.5%) (Nematoda). The helminth fauna in Iberian lynx is compared with that of L. canadensis and L. rufus in America, and for L. lynx in Eurasia. The potential relationships between the parasitological data and some geographical, historical and dietary factors are discussed.

Striped possums (Dactylopsila trivirgata) are small arboreal marsupials for which limited medical information is known. Mastophorus muris is a gastric spirurid nematode of rodents that uses insects as intermediate hosts. Three cases of gastric spiruridiasis caused by M. muris in captive striped possums are reported for the first time. Diagnosis was made by the presence of adult nematodes in regurgitant and at necropsy. Low numbers of nematode ova shed intermittently in possum feces made evaluation of treatment success difficult. No histopathologic abnormalities were identified in one case. Control of M. muris in captive possum colonies may be achieved by interrupting the life cycle of the parasite.

Background The prevalence of parasitic infections among commensal animals such as black and brown rats in many tropical countries is high and in comparison with studies on rodents in temperate climates, little is known about the community structure of their parasites. Rodent borne parasites pose threats to human health since people living in close proximity to rodent populations can be exposed to infection. Methods The helminth community structures of two urban rat populations in Kuala Lumpur, Malaysia were investigated. The rats were from two contrasting sites in the city caught over a period of 21 months in 2000-2002. Results Eleven species of helminth parasites comprising seven nematodes (Heterakis spumosum, Mastophorus muris, Nippostrongylus brasiliensis, Syphacia muris, Pterygodermatites tani/whartoni, Gongylonema neoplasticum, Angiostrongylus malaysiensis), three cestodes (Hymenolepis (Rodentolepis) nana, H. diminuta and Taenia taeniaeformis) and one acanthocephalan (Moniliformis moniliformis) were recovered from 346 Rattus rattus and 104 R. norvegicus from two urban sites, Bangsar and Chow Kit, during 2000-2002. Rattus rattus harboured over 60% of all helminths compared with R. norvegicus, although both host species played a dominant role in the different sites with, for example R. norvegicus at Bangsar and R. rattus at Chow Kit accounting for most of the nematodes. Overall 80% of rats carried at least one species of helminth, with the highest prevalences being shown by H. diminuta (35%), H. spumosum (29.8%) and H. nana (28.4%). Nevertheless, there were marked differences in prevalence rates between sites and hosts. The influence of extrinsic (year, season and site) and intrinsic (species, sex and age) factors affecting infracommunity structure (abundance and prevalence of infection) and measures of component community structure were analyzed. Conclusions Since at least two species of rat borne helminths in Kuala Lumpur have the potential to infect humans, and these showed high prevalences in the rats, the assessment and regular monitoring of infections carried by wild rodents have important roles to play in public health.

The helminths of two sympatric species of rodents, the striped field mouse Apodemus agrarius and the yellow-necked mouse, Apodemus flavicollis from Slovakia were studied to determine whether there are similarities in the composition of the helminth fauna of two closely related host species living in the same area. A total of twelve species of helminths were identified in these rodent populations, including Brachylaima sp. (Trematoda); Hymenolepis diminuta (Rudolphi, 1819), Mesocestoides sp. larvae, Rodentolepis fraterna (Stiles, 1906), Rodentolepis straminea (Goeze, 1782), Skrjabinotaenia lobata (Baer, 1925), Taenia taeniaeformis larvae (Batsch, 1786) (Cestoda); Aonchotheca annulosa (Dujardin, 1845), Heligmosomoides polygyrus (Dujardin, 1845), Heterakis spumosa Schneider, 1866, Mastophorus muris (Gmelin, 1790) and Syphacia stroma (Linstow, 1884) (Nematoda). In A. agrarius, H. polygyrus was the most prevalent, as well as the most abundant helminth, but R. fraterna was the species with the highest mean intensity. In contrast, S. stroma dominated the A. flavicollis helminth fauna with the highest prevalence, mean abundance and mean intensity. Both rodent populations harboured nine helminth species, although the mean individual species richness was significantly higher in A. agrarius than in A. flavicollis. The analysis of helminth diversity at both component and infracommunity levels revealed differences between the two rodent populations, which are most likely attributable to the specific host ecology.

Differences in helminth faunal composition, distribution and abundance were studied in three habitats on an island on which the Polynesian rat, Rattus exulans (Peale), is the only rodent present. The effects of season and of host age and sex were also included in the analysis. Habitat had a statistically significant effect on the prevalence and/or abundance of all seven parasites included in this study. Season influenced four species (Brachylaima apoplania, Capillaria sp., Heterakis spumosa and Mastophorus muris) but had little or no detectable effect on the remaining three (Capillaria hepatica, Hymenolepis diminuta and Syphacia muris). Of the two intrinsic variables, age but not sex was found to have an effect. A comparison of the effects of each variable on parasite prevalence confirmed that habitat was the most important of the four variables. In a prior study on the influence of habitat on host population dynamics on this island, between-habitat differences were shown to include adult longevity, total population density and the seasonal availability and abundance of various food types. These factors, together with physical differences in the microhabitat and the parasite's life cycle, help to provide explanations for the observed results.

Black rats (Rattus rattus) and their stomach nematodes (Mastophorus muris) were historically introduced to islets at Palmyra Atoll in the central Pacific Line Islands. To investigate patterns of parasitism, we trapped rats and quantified nematodes on 13 islets of various sizes and habitat types. Most rats were parasitized (59%) with an average of 12 worms per infected rat. Islet size did not greatly influence parasite population biology. Nematodes also did not appear to affect rat condition (weight to skull length). The only strong and consistent factor associated with the mean abundance of nematodes in rats was habitat (dominant cover and locally dominant plant species). Thus, nematodes were much more abundant in rats from sites dominated by coconut trees (Cocos nucifera). Coconut trees may also be an introduced species at Palmyra Atoll.

The seasonal and long-term population dynamics of helminths parasitizing voles suggested that density-dependent factors might be important in the population dynamics of common species, whereas density-independent factors predominate in the regulation of the rare species. To test this, we used single and multiple regression to analyse the effects of climatic factors and host density on populations of six species of vole helminths over 12 years. The data do support the idea of a difference between common and rare species of helminths, but they clearly do not support the above hypothesis. The common helminths Heligmosomum mixtum (Nematoda) and Catenotaenia sp. (Cestoda) responded to changes in temperature sum (>5° C days) and precipitation during summer. The combined effect of climatic factors and host density explained most of the variation in the long-term dynamics of these common species. By contrast, the long-term dynamics of the rare helminths Paranoplocephala kalelai (Cestoda), Mastophorus muris, Capillaria sp. and Syphacia petrusewiczi (Nematoda) were explained less well by weather and host density than those of the common ones. Furthermore, the common and rare helminths differed in some ways in their responses to climatic factors.

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The present study analyses the helminth communities found in one hundred and two specimens of Martes martes from the Iberian Peninsula and the Balearic Archipelago. The component community is constituted by seventeen helminth species, which frequency and mean abundance show a bimodal pattern. The set of core species is constituted by the trichurids Pearsonema plica, Eucoleus aerophilus and Aonchotheca putorii (72.2% of total helminth individuals found), while the remaining can be considered satellite species. Significant co-occurrences were found among E. aerophilus/A. putorii and E. aerophilus/P. plica. These results demonstrate the great importance of earthworms within the diet of pine marten and contribute to the knowledge of the pine marten’s food ethology, since this kind of prey normally goes undetected in diet studies. Several helminth species, as Sobolevingylus petrowi, Centrorhynchus aluconis, Uncinaria criniformis, Mastophorus muris and Spirura rytipleurites seurati seem to show geographical distributions limited to insular ecosystems. Moreover, helminth communities of M. martes among four Spanish territories, including mainland and insular areas, are characterized and compared.

Eighty-five Eurasian badgers, Meles meles (Linnaeus, 1758), from four mainland biogeographic Spanish areas were analysed for helminths. Seventeen helminth species were found: Brachylaima sp., Euparyphium melis and Euryhelmis squamula (Trematoda), Atriotaenia incisa and Mesocestoides sp. (Cestoda) and Aelurostrongylus pridhami, Angiostrongylus vasorum, Aonchotheca putorii, Crenosoma melesi, Mastophorus muris, Molineus patens, Pearsonema plica, Physaloptera sibirica, Strongyloides sp., Trichinella sp., Uncinaria criniformis and Vigisospirura potekhina hugoti (Nematoda). In the Mediterranean area, Aonchotheca putorii, M. patens, Strongyloides sp., and U. criniformis were more prevalent in the occidental part, whereas Atriotaenia incisa and Mesocestoides sp. cestodes showed higher values on the continental slope. Metastrongyloid species (Aelurostrongylus pridhami, Angiostrongylus vasorum and Crenosoma melesi) were only detected in the occidental Mediterranean area. In contrast, spirurid species (Mastophorus muris and Vigisospirura potekhina hugoti) were almost restricted to the continental Mediterranean area. Helminthological differences between areas may result from the badger diet, abiotic factors and biocenosis present in each biogeographic area.

This study documents the parasite assemblage of Rattus colletti (Thomas, 1904) from the Adelaide River flood plain, Northern Territory, Australia. In total, six species of helminth (comprising two cestodes, one trematode and three nematodes), and four species of arthropod (comprising one tick, one mite, one flea (identified to family level) and one louse (identified to generic level)) were found. In spite of the hosts being present in high numbers the helminth assemblage was depauperate, characterised by low prevalence and abundance, both being higher in wet seasons. More helminths were found in larger animals. The most prevalent helminth was from the Trichostrongylina, Nippostrongylus typicus (Mawson, 1961). The assemblage was characterised as having two heirloom species (N. typicus and Hymenolepis diminuta (Rudolphi, 1819)), a host capture (Raillietina celebensis (Janicki, 1902) and a cosmopolitan species (Mastophorus muris (Gmelin, 1790)) as well as occasional infections. When compared with the helminths from a single population of Rattus sordidus (Gould, 1858) a similar number of species were found, three species being in common, and both were depauperate when compared with the more extensively surveyed faunas of Rattus fuscipes (Waterhouse, 1839) and Rattus leucopus (Gray, 1858).

Examination of stomach contents from 191 Rattus r. rattus, trapped over 12 months in an area of bush in the Manawatu district, revealed that 123 (64.4%) of the rats were infected with Physaloptera getula (Physalopteridae) and 39 (20.4%) with Mastophorus muris (Spiruridae). The high prevalence of P. getula did not vary significantly during the year, but there were marked seasonal variations in the numbers of worms per rat, the highest mean counts occurring in autumn and the lowest in late winter and spring. The prevalence of M. muris varied significantly through the year, and was highest in autumn. Mean worm counts per rat appeared to be biphasic, with peaks in spring and autumn; however, since only small numbers of animals were infected, this may not represent what actually occurs. The majority of infections with both nematode species comprised less than 10 worms. Possible reasons for the seasonal variation in prevalence and intensity of infections are discussed. Circumstantial evidence suggests ...

Hamada G. S. and Wertheim G. 1978. Mastophorus muris (Nematoda: Spirurina): ultrastructure of somatic muscle development. International Journal for Parasitology 8 ; 405–414. The ultrastructure of the somatic muscle cells of the adult and six developmental stages of Mastophorus were studied. In all stages the cells consisted of a contractile region containing myofibrils separated by dense bands and a noncontractile region with nuclei, mitochondria, glycogen, lipid droplets and vesicles. Two sizes of myofilaments were present. The dense band contained T tubules and sarcoplasmic reticulum, and, in more advanced stages, support filaments, glycogen and dense bodies. The contractile region of the adult muscle cell consisted of several hundred irregularly shaped myofibrils arranged in a random pattern. This pattern of myofibrils was defined as irregular-coelomyarian. The third stage larva had a shallow-coelomyarian myofibril configuration, which changed to coelomyarian in the late third stage through the addition of new myofibrils at the apical contractile border. In the fourth stage larvae, the subdivision of existing myofibrils changed the pattern to irregular-coelomyarian.

Nine helminth species (5 cestodes, 4 nematodes) were recovered from 128 Sigmodon hispidus collected in two mesic and three upland habitats in western Texas. These are Taenia taeniaeformis and T. rileyi (both as larvae), Monoecocestus sigmodontis, Raillietina bakeri, Hymenolepis diminuta, Mastophorus muris, Syphacia sigmodontis, Physaloptera sp., and an unidentified oxyuroid. Utilyzing an index of similarity, comparisons were made between the helminth faunas at the five collecting sites and also between the two habitats in Texas and three habitats in Florida. The data suggest that host habitat has a marked influence on the composition of the helminth fauna of Sigmodon hispidus. The present survey was undertaken in part to compare the helminth fauna of the cotton rat, Sigmodon hispidus Say and Ord, of western Texas with published accounts of parasites collected elsewhere from the same host. The helminths of the cotton rat are known well (Kinsella 1974), but all of the previous reports are from hosts originating in much more mesic localities in the southeastern United States or Central and South America. Even reports issuing from Texas (Smith 1908; Hugghins 1951; Melvin and Chandler 1951; Eads and Hightower 1952; Scott and Blynn 1952) are of hosts captured in the central or coastal parts of the state where the mean annual precipitation ranges from 60 to 125 cm. The mean annual precipitation for much of western Texas is less than 50 cm. The present study also seeks to quantify what similarities may exist in helminth faunas of cotton rats collected in mesic and upland habitats in western Texas. Kinsella (1974) demonstrated some striking qualitative differences in a comparison of the helminth faunas of the 1 Present address: Epidemiologic Studies Program, Texas Tech Univ. Health Science Centers, 152 E. Stenger, San Benito, Texas 78586.

The fine structure of the cuticle of the infective larva and of the adult male and female was studied in Mastophorus muris, a stomach parasite of rats. The infective larva develops in the hemocoel of the insect intermediate host where it lays coiled in a gelatinous cyst with its ventral surface outwards. In transverse sections of uncoiled larvae the cuticle is 2.4 uAm thick and consists of a cortex in which a narrow band of striations is visible, a median layer, and one layer of basal fibers. In coiled specimens the ventral cuticle of the larva is stretched and thin, whereas the dorsal cuticle is thicker, folded, and appears compressed. The cuticle of the adult worms is 17-74 Arm thick and consists of an outer fuzzy coat, an external trilaminar structure, a granular external cortex, and an internal cortex containing striated fibers with a periodicity of 200 nm. The median layer consists of homogeneous, electron-dense material in which less electron-dense material is seen. Three sublayers of fibers comprise the basal layer. The innermost basal lamella consists of striated fibers with a 140-nm period. The ultrastructure of nematode cuticle has been reviewed by Lee (1966b, 1972), Bird and Bird (1969), and Bird (1971). With the exception of several species of filariae, representatives of the suborder Spirurina have been studied only by light microscopy (Bogoyavlenski, 1961). In the present study the cuticular ultrastructure of adult Mastophorus muris, parasitic in the stomach of rats, and of its infective third stage larva, parasitic in the hemocoel of the cockroach, is described. MATERIALS AND METHODS Mastophorus muris, isolated from city rats (Wertheim, 1963), was maintained in the outbred Hebrew University Sabra strain of rats and in Blatella germanica. Roaches, fasted for 48 hr, were infected with larvated eggs mixed with powdered wet oat flakes. The rats, 80-100 g, were infected by gavage with 15 gelatinous cysts containing 3rd stage larvae, dissected from the roaches 4-5 weeks postinfection. For this study adult worms were removed from Received for publication 6 September 1977. * On Fellowship Leave from LaGuardia Community College, City University of New York, Long Island City, New York. the stomach of ether-killed rats, infected 60 days previously. The 3rd stage larvae were freed from the gelatinous cysts by treatment with artificial gastric juice for 10 min at 37 C. Worms were rinsed in saline and cut into appropriately sized cylinders. Tissue was fixed for 1-2 hr in ice-cold 2.5% glutaraldehyde in either phosphate or cacodylate buffer pH 7.4. Worms were then rinsed in 3 changes of cold buffer for 1 hr. Postfixation was carried out for 1 hr with ice-cold 1% osmium tetroxide in one of the above mentioned buffers. The tissue was rinsed in distilled water and in 2% uranyl acetate in distilled water, dehydrated in an ethanol series, transferred to propylene oxide, and left overnight in a 1:1 mixture of propylene oxide-Epon. Following 2 hr in fresh Epon in vacuo (Bird, 1971), the tissue was embed ed in fresh Epon in flat silicone rubber molds, oriented, and polymerized at 60 C for 48 hr. Blocks were sectioned with glass knives on a LKB Ultratome. Thick (0.5-1.0 tum) sections were stained with 1% toluidine blue in 0.5% sodium borate at 60 C. Selected areas were thin sectioned and picked up on naked or formvarcarbon coated grids, stained with uranyl acetate and lead citrate, and examined with a Philips 300 electron microscope at 60 kV. Worms for scanning electron microscopy were prepared according to the method descibed elsewhere (Wertheim and Chabaud, 1977). FIGURES 1, 2. Third stage larva of Mastophorus muris. 1. Electron micrograph of a transverse section from the middle of uncoiled larva. The striated band is visible near the interior border of the cortex. Cortex (C), median (M), and basal (B) layers. X 53,000. 2. Transverse section of the lateral alae of larva. Body wall layers are retained, cortex (C), median (M), and basal (B), and an electron-dense granular deposit (G) is visible between the cortex (C) and median (M) layers. Cyst debris is visible on external surface of the cuticle. X 20,000.

Thirty-eight cotton rats, Sigmodon hispidus, were collected in southern Virginia and examined for their helminth fauna. The cestodes recovered were: Choanotaenia nebraskensis (8% incidence), Hymenolepis diminuta (18%) and Raillietina bakeri (18%) from the intestine, and larval Taenia taeniaeformis (16%) from the liver. This is the first report of C. nebraskensis from the cotton rat. The nematodes found were Longistriata adunca (76%) from the intestine and Mastophorus muris (42%) from the stomach. The heaviest infections were produced by L. adunca (41 worms per infected host) and R. bakeri (21 worms per infected host). Twenty hosts harbored two or more species of worms. Mastophorus muris and C. nebraskensis were more common in female than male hosts. The sex ratio of the 1201 L. adunca collected was determined. Young cotton rats have a 1: 1 female worm to male worm sex ratio. Older hosts have more female than male worms. INTRODUCTION The helminth fauna of the cotton rat, Sigmodon hispidus, is relatively well known. Baylis (1945) and Melvin and Chandler (1950) published species lists of cotton rat helminths from the "southern United States" and Florida and Texas, respectively. Harkema and Kartman (1948) compared the helminth fauna and ectoparasites of cotton rats from North Carolina and Georgia. They studied the general incidence and intensity of infection, seasonal variation and other host-parasite relationships. Hugghins (1951) surveyed and compared the helminths and ectoparasites of roof rats and cotton rats in Texas. Lanier (1951) studied the helminths of Sigmodon hispidus in southern Florida. Recently, Kinsella (1974) compared the helminths of cotton rats from saltwater and freshwater marshes in northern Florida. He also included a checklist of all the helminths known from the cotton