1. A new species of the genus Ptychobothrium Loennberg 1889, recovered from the intestine of the Hying fish Cypselttrus poecthpterus Cuv. and Val., off the coast of Waltair, is described.

2. Ptychobothrium cypseluri n.sp. differs from P. bclottes (Dujardin, 1845), the only other known species of the genus, in the nature of the ovary, uterus and the number of testes.

In soil samples taken from around trees of Primus serotina and shrubs near the writer's house at Ede, Holland, the nematode population proved to consist mainly of a hitherto undescribed species of Trichodorus. Small numbers of the same species were found in many other places including a strawberry field on light sandy soil near Beverwijk, where it occurred together with T. primitivus (de Man, 1884) Micoletzky, 1922; a garden at Middelharnis (sandy loam) and in arable land at Ottersum (sandy soil). No data could be collected on its food habits.

This is the third and final paper of a series which constitutes a report on a biological investigation of sewage, undertaken by the writer as a Research Scholar of the Grocers' Company. Of the previous two papers, the first (1929) describes a colorimeter and the second (1930) is a general report on the work as a whole. Since the nematodes form a neglected and not inconsiderable section of the fauna of most sewage plants, special attention was accorded them, and an account of them is given separately here instead of rendering the general report unbalanced and unwieldy by being included there.

During the microscopical examination of the debris collected by flotation from soil infected with the potato eelwormHeterodera schachtii Schmidt, the presence of small numbers of cysts unlike those typical of the potato strain has frequently been observed. The distinguishing characters of these cysts are their dark colour and their lemon-like shape. Similar cysts were seen by chance during observations on “clean” soil which was being used as a control to pot experiments with eelworm-infected soil. This “clean” soil had been obtained from a heap of top-spit material which had been removed from a field on Winches Farm known to have been under grass for at least twenty years, and probably longer.

138 wild duck of five species: Anas plalyrhynchos plalyrhynchos, A. penelope, A. crecca, A. acuta and Spatula clypeata taken in East Anglia, England were examined for trematodes, cestodes, nematodes and acanthocephala. Prevalence data are tabulated and maximum intensities recorded. The waterfowl were taken in the autumn and early winter and were presumed to be migrants coming in from western Europe.

Steiner (1931) published a brief note on the occurrence of disease in a yam tuber, from Jamaica, with which there were associated large numbers of a species of nematode which he placed in the genus Hoplolaimus. Steiner and LeHew (1933) published a description of the nematode parasite obtained from this yam and gave it the name Hoplolaimus bradys. At a later date Steiner and Buhrer (1934) recorded the same parasite from a yam coming from Porto Rico.

In the literature which deals with the gape-worm, Syngamus trachea, found commonly in England, its presence has been recorded from a fair variety of birds. It has been found several times in the starling—Nathusius (1837), Megnin (1883) and, among others, by Lewis (1925). Dujardin records having found it in the magpie, Corvus pica, (1845) Megnin (1883) found it in the swift (cypselus apus), green woodpecker (Picus viridis), black stork (Ciconia nigra) and in the pheasant and partridge. It has further been recovered by Lewis (1925) from the rook (Corvus frugilegus), thrush (Turdus musicus) and jay (Garrulus glandarius), while in the Ministry of Agriculture Leaflet No. 58, the sparrow and linnet are also cited as being occasional hosts, and Walker (1886) has found it in the robin. The present writers have found a closely related species, S. merulae (Baylis, 1926) in the tracheae of four blackbirds which came into the laboratory during the summer. Though these birds seem to be only occasional hosts, most of the authors stating that the infections occurred only in young birds while the adults are comparatively free from this worm, yet a high percentage of young birds are frequently found to be carrying this parasite: for instance, Elton and Buckland (1928) in a batch of 33 young rooks obtained from the Oxford district, found 31 infected, while of 8 old birds only four were infected and these only lightly. Lewis in 1926 found 35 per cent. of a sample of starlings infected but he did not notice the age of the birds. Morgan examined two nests of young starlings and found that all of one batch harboured S. trachea. He suggests that they may have become infected from the earthworms brought in by the parent birds as food.

The present study considers the influence of the trophic status of three Kashmir Himalayan lakes on the patterns of helminth infracommunities in populations of three species of fish during 2006 to 2008. Data were collected from three lakes of differing trophic status in the Kashmir Himalayas, namely Anchar, a hyper(eu)trophic lake; Dal, a eutrophic lake; and Manasbal, a meso(eu)trophic lake. Three species of fish examined included the native fish Schizothorax niger Heckel and two exotic species – Carassius carassius (Linnaeus) and Cyprinus carpio Linnaeus. The analysis of data showed a clear habitat effect on the abundance pattern of helminth species, thus revealing lake-specific differences in parasite infracommunities of both S. niger and C. carassius. Helminth infracommunity richness was the highest in host populations from the Anchar lake compared to other two lakes. Low values in the Manasbal lake emphasize the low diversity of their helminth infracommunities. On the other hand, there was no observed pattern of community structure in the case of C. carpio in the three lake sites. However due to bias in sampling there was no distinct effect of fish body size on parasite infracommunity structure, although the present results do show that fish parasite data can be meaningful in diagnosing changes in the trophic condition of eutrophic lakes.

We evaluated the relationship between infection by proteocephalid cestodes and the sex and weight classes of tucunaré (Cichla piquiti) captured between August 1999 and June 2001 in the Volta Grande Reservoir, Minas Gerais, Brazil. A total of 96 fish, 75.9 ± 9.3% males and 88.9 ± 6.4% females, were parasitized by Proteocephalus macrophallus and P. microscopicus, with total mean intensities of 76.6 ± 23.9 and 145.2 ± 36.7, respectively, during this period. In the majority of the months analysed, males showed 71.4–100% prevalence of parasitism and females 80–100%. Although there was no significant difference, females showed a higher mean intensity of infection (145.2 ± 36.7) than males (76.6 ± 23.9). Fish weighing 300–800 g showed a higher mean abundance of parasites (P < 0.05) compared with the biggest specimens weighing 801–2750 g. Analysing both males and females together, the greatest mean intensities of infection were found in October and December (P < 0.05) independent of the year, which coincides with the months of highest rainfall. These results show that fish living in reservoirs may be more susceptible to intermediate hosts than those that live in rivers.

The genus Oswaldocruzia Travassos, 1917 includes approximately 90 species that are parasitic on amphibians and reptiles around the world, of which 43 occur in the neotropical region. However, molecular data supporting the taxonomic status of most species of the genus are scarce, and their phylogenetic relationships remain unknown. Using specimens of four molineid taxa (Oswaldocruzia belenensis Santos, Giese, Maldonado Jr. and Lanfredi, 2008; Oswaldocruzia chabaudi Ben Slimane & Durette-Desset, 1996, Oswaldocruzia chambrieri Ben Slimane & Durette-Desset, 1996 and Kentropyxia hylae Feitosa, Furtado, Santos and Melo, 2015) from amphibian hosts collected in different regions of Pará, Brazil, we conducted morphological studies, molecular analyses and phylogenies (maximum likelihood and Bayesian inference) using the cytochrome c oxidase subunity I (Cox1) gene. The newly generated sequences were compared with those of ten publicly available Cox1 sequences of Oswaldocruzia from Mexico. Our findings demonstrated significant differences between the sequences of amazonian specimens and sequences from specimens collected in Mexico, and we suggest that host–parasite cospeciation or habitat use might be related to molineid evolution in amphibian hosts. Additionally, this work presents new hosts and new geographical records for species of Oswaldocruzia from the neotropics.

Parasites commonly share their hosts with specimens of the same or different parasite species, resulting in multiple parasites obtaining resources from the same host. This could potentially lead to conflicts between co-infecting parasites, especially at high infection intensities. In Pool Los Juncos (Patagonia, Argentina), the amphipod Hyalella patagonica is an intermediate host to three parasites that mature in birds (the acanthocephalan Pseudocorynosoma sp. and larval stages of two Cyclophyllidea cestodes), in addition to a microsporidian (Thelohania sp.), whose life cycle is unknown, but very likely to be monoxenous. The aim of this study was to describe interactions between these parasite species in their amphipod host population. Amphipods were collected monthly between June 2002 and January 2004 to assess parasite infection. Infection prevalence and mean intensity were greatest in larger male amphipods for all parasite species. We also found a positive association between Thelohania sp. and both Pseudocorynosoma sp. and Cyclophyllidea sp. 1 infections, though Pseudocorynosoma sp. and Cyclophyllidea sp. 1 were negatively associated with each other. We conclude that contrasting associations between parasite species may be associated with competition for both food intake and space in the haemocoel.

Sequence data were combined with morphological analyses to identify two lepocreadiid trematode species from jellyfishes and fishes. Three species of jellyfish were captured within Port Phillip Bay, Australia, and three species of fish that feed on jellyfish were obtained from Moreton Bay (Queensland) and Port Phillip Bay and Portland (Victoria). The digeneans were distributed throughout most parts of the jellyfish. Opechona cf. kahawai Bray & Cribb, 2003 parasitized the scyphozoan jellyfish Aequorea eurodina and the scombrid fish Scomber australasicus. Cephalolepidapedon warehou Bray & Cribb, 2003 parasitized the scyphozoans Pseudorhiza haeckeli and Cyanea annaskala, and the centrolophid fishes Seriolella brama and Seriolella punctata. Intensities ranged from four to 96 in the jellyfish, and one to 30 in the fish. For both trematode species, internal transcribed spacer 2 of ribosomal DNA sequences from mature adults in the fishes matched those from metacercariae from the jellyfish. This is the first record of larval stages of C. warehou and O. cf. kahawai, and the first use of DNA sequencing to identify digenean trematode metacercariae from jellyfish. Three new host records are reported for C. warehou and two for O. cf. kahawai.

Timoniella spp. are cryptogonimid flukes (Digenea: Cryptogonimidae) that parasitize the guts of fish in brackish waters. Timoniella imbutiforme, a species from the Mediterranean Sea, is recorded in the Black Sea, while T. balthica has been described from the Baltic Sea. In this paper, we clarify the taxonomic status of Timoniella populations in the Baltic and Black seas. Adults and metacercariae of Timoniella spp. were sampled from localities in the Mediterranean Sea (France), Black Sea (Ukraine) and Baltic Sea (Germany) and subjected to molecular and morphological analysis, including Bayesian phylogenetic reconstruction based on concatenated sequences of ITS1–ITS2–28S. This allowed us to construct a new key to species of the genus Timoniella. Our results suggest that T. balthica forms part of the Boreal–Atlantic relict fauna of the Black Sea and should now be considered a junior synonym of T. imbutiforme.

Relationships between the species diversity of different taxa, the mean number of articles published per year on each taxon, and the mean impact factor of the journals in which they appear, were examined across six taxa of helminths: Nematomorpha, Acanthocephala, Monogenea, Trematoda, Cestoda and Nematoda, the latter including only animal parasitic nematodes. The mean annual output of scientific articles per taxon was not related to the species diversity of these taxa or, at least, not significantly. Thus, the large volume of publications on nematodes is not merely a reflection of their estimated diversity. There were significant differences among taxa in the mean impact factor of the journals in which papers on each taxon appeared, with nematodes having the highest mean score, followed by trematodes and cestodes. In addition, across the six taxa, the mean journal impact factor correlated positively and significantly with the mean annual number of papers published: not only are there more papers published on nematodes and trematodes than on nematomorphs or acanthocephalans, but they are also generally published in higher-ranking journals. These results suggest that there is an increasing gap in the quantity and general importance of the research carried out on different helminth taxa.

The production of tambaqui Colossoma macropomum has been undergoing financial losses due to parasitic infection by the acanthocephalan Neoechinorhynchus buttnerae, raising an alert for aquaculture in South America. The lack of adequate treatment and use of unlicensed chemicals encourages research for alternative solutions with minimal side effects. The objectives of this study were to evaluate the in vitro antiparasitic potential of commercial nutraceutical products (Natumix® and BioFish®) against N. buttnerae and to assess the respective in vivo toxic effects on the host tambaqui. For in vitro assays, parasitized fish were necropsied for acanthocephalans sampling. The parasites were exposed to three concentrations (0.078, 0.313 and 1.25 mg/ml) of each product, as well as controls (one without product and another with a solubilizer). For the in vivo acute toxicity test, juvenile fish (<0.1 g) were exposed to five increasing concentrations of each product. Mortality of tambaqui was recorded at 24, 48, 72 and 96 h. The estimated lethal concentration (LC) for 10, 50, 90 and 99% of fish was determined to classify the toxicity of the products on the target species. After in vitro efficacy tests, the highest concentrations (1.25 mg/ml) caused 100% mortality of the parasites in both products, but only Natumix® caused 100% mortality using the intermediate concentration (0.313 mg/ml) after 24 h. According to the acute toxicity result, the LC50 classified the nutraceutical products as slightly toxic for tambaqui. The tested products had a parasiticidal effect on N. buttnerae, and the toxicity test showed that both products have therapeutic potential when added to the diet.

The gastropod parasitic nematode Phasmarhabditis hermaphrodita has been formulated into a successful biological control agent (Nemaslug®, strain DMG0001) used to kill slugs on farms and gardens. When applied to soil, P. hermaphrodita uses slug mucus and faeces to find potential hosts. However, there is little information on what cues other species of Phasmarhabditis (P. neopapillosa and P. californica) use to find hosts and whether there is natural variation in their ability to chemotax to host cues. Therefore, using chemotaxis assays, we exposed nine wild isolates of P. hermaphrodita, five isolates of P. neopapillosa and three isolates of P. californica to mucus from the pestiferous slug host Deroceras invadens, as well as 1% and 5% hyaluronic acid – a component of slug mucus that is highly attractive to these nematodes. We found P. hermaphrodita (DMG0010) and P. californica (DMG0018) responded significantly more to D. invadens mucus and 1% hyaluronic acid than other strains. Also, P. hermaphrodita (DMG0007), P. neopapillosa (DMG0015) and P. californica (DMG0017) were superior at locating 5% hyaluronic acid compared to other isolates of the same genera. Ultimately, there is natural variation in chemoattraction in Phasmarhabditis nematodes, with some strains responding significantly better to host cues than others.

As part of the international joint projects working towards the control of taeniosis/cysticercosis in Asia Pacific, epidemiological studies on Taenia solium cysticercosis have been carried out in high-incidence populations, such as minority groups in Thailand. To assess the epidemiology of cysticercotic infections in pigs in the hill-tribe minority villages (Karen) in Tak province, Thailand, we conducted serological screening and necropsies. The patterns of antibody response to T. solium antigens were then investigated using immunoblot assays. Of the 188 pig serum samples tested for antibody responses to partially purified low-molecular-weight antigens of T. solium cyst fluid, positive responses were detected in 37 samples (19.7%). Based on these results, 16 pigs (10 seropositive and 6 seronegative) were necropsied for investigation of cysticerci and intestinal parasites. All seropositive pigs were coinfected with both T. solium and Taenia hydatigena cysticerci, except one, which was infected with T. hydatigena alone. Three of the six seronegative pigs were confirmed to be infected with T. hydatigena. Pigs infected with T. solium showed much stronger antibody responses than those infected with T. hydatigena. Our results demonstrate the co-occurrence of two swine cysticercoses due to T. solium and T. hydatigena in the studied areas. This study also reveals the importance of direct confirmation of the presence of cysticerci by necropsy after serological screening. In addition to the prevalence of swine cysticercosis in these endemic areas, our findings also reveal potential implications for the development of serological diagnostic assays for swine cysticercosis.

To test the hypothesis that modulation of hepatic microsomal sulphoxidation and sulphonation by the cytochrome P450 inhibitor piperonyl butoxide could increase bioavailability of albendazole, the present study was undertaken to understand the pharmacokinetics of albendazole in goats at a dose of 7.5 mg kg− 1 body weight with and without co-administration with piperonyl butoxide at 63.0 mg kg− 1 body weight. Plasma albendazole sulphoxide metabolite, the anthelmintically active moiety, reached its maximum concentration of 0.322 ± 0.045 μg ml− 1 and 0.384 ± 0.013 μg ml− 1 at 18 h and 24 h after administration of albendazole alone and co-administration of albendazole with piperonyl butoxide, respectively. Analysis of the data revealed statistically increased albendazole sulphoxide levels at 24 (P <  0.001), 30 (P <  0.001) and 36 h (P <  0.01) after administration of albendazole with piperonyl butoxide, with statistically increased levels of albendazole sulphone at 24, 30 and 48 h after administration. No significance difference (P > 0.05) in values of maximum concentration (normal and calculated) could be observed between groups of goats. However, values of time to reach the concentration maximum (normal and calculated), area under the concentration–time curve (0–∞ and calculated), minimum residence time, distribution half-life, elimination half-life and total area under the first movement of plasma drug concentration–time curve were significantly higher (P <  0.05) in plasma levels of albendazole sulphoxide in goats following single oral co-administration of albendazole with piperonyl butoxide. The faecal egg count reduction and lower 95% confidence limit for the group treated with albendazole alone were 97 and 68%, while for co-administration of albendazole and piperonyl butoxide the values were 99 and 97%, respectively. The ED50 for egg hatch was 0.196, indicating suspected resistance to benzimidazole anthelmintics. The drug combination proved efficacious against an albendazole-resistant nematode parasite population in goats.

Symbiotic bacteria are a common feature of many animals, particularly invertebrates, from both aquatic and terrestrial habitats. These bacteria have increasingly been recognized as performing an important role in maintaining invertebrate health. Both ecto- and endoparasitic helminths have also been found to harbour a range of bacterial species which provide a similar function. The part symbiotic bacteria play in sustaining homeostasis of free-living invertebrates exposed to anthropogenic pressure (climate change, pollution), and the consequences to invertebrate populations when their symbionts succumb to poor environmental conditions, are increasingly important areas of research. Helminths are also susceptible to environmental stress and their symbiotic bacteria may be a key aspect of their responses to deteriorating conditions. This article summarizes the ecophysiological relationship helminths have with symbiotic bacteria and the role they play in maintaining a healthy parasite and the relevance of specific changes that occur in free-living invertebrate–bacteria interactions under anthropogenic pressure to helminths and their bacterial communities. It also discusses the importance of understanding the mechanistic sensitivity of helminth–bacteria relationships to environmental stress for comprehending the responses of parasites to challenging conditions.

In angiostrongyliasis, chronic parasite-induced granuloma formation can lead to tissue destruction and fibrosis. Here, the histomorphology of granulomatous fibrosis and proteinase production in the lungs of Angiostrongylus cantonensis-infected Sprague-Dawley rats were investigated. The relationship between metalloproteinases and granulomatous fibrosis was investigated following infection of each rat with 60 infective larvae. Granulomata and fibrosis were marked in the lungs of rats on day 180 post-inoculation. Reverse transcriptase polymerase chain reaction of lung mRNA showed an up-expression of proinflammatory cytokine including tumour necrosis factor alpha (TNF-α) and interleukin-1 beta (IL-1β). According to Western blot analysis, matrix metalloproteinase-2 (MMP-2) proenzyme was presented in the lungs of uninfected and infected rats, and partial conversion of 72 kDa proenzyme to the 64kDa active form occurred in infected rats. In addition, increased protein levels of MMP-9 and MMP-13 were detected in infected lungs, but were undetectable in controls. The results suggest that TNF-α, IL-1β, MMP-2, -9, and -13 may be associated with the granulomatous fibrosis.