Metazoan parasite communities of Crassostrea gigas and Ostrea edulis from Great Britain, Crassostrea virginica from Mexico, and Saccostrea commercialis from Australia are described and summarized in terms of species composition, species richness, total number of individuals and dominance. Metazoan parasite communities in all host species were composed of turbellarians and the metacercarial stage of digeneans, with the exception of S. commercialis where only metacercariae were found. Arthropods, including one copepod and one mite species, were present only in British oyster species. All metazoan parasite communities of oysters had few species and low density of individuals. Richest communities were found in C. virginica at both component and infracommunity level. The least diverse component community occurred in S. commercialis. Infracommunities in O. edulis and S. commercialis never exceeded one species per host. The host response against parasites is suggested as the principal factor responsible for depauperate parasite communities of oysters. Environmental factors characteristic of tropical latitudes are likely to have enhanced both the number of species and the densities of parasites per host in the infracommunities of C. virginica.

A parasitological survey of terrestrial slugs and snails was conducted at popular dog walking locations across the city of Nottingham, with the intensions of finding gastropods infected with parasites of medical (or veterinary) importance such as lungworm (metastrongyloid nematodes) and trematodes. A total of 800 gastropods were collected from 16 sites over a 225 km2 area. The extracted nematodes and trematodes were identified by molecular barcoding. Of the 800 gastropods collected, 227 were infected (172 had nematode infections, 37 had trematode infections and 18 had both nematode and trematode infections). Of the nematode infected gastropods genotyped, seven species were identified, Agfa flexilis, Angiostoma gandavense, Angiostoma margaretae, Cosmocerca longicauda, Phasmarhabditis hermaphrodita, Phasmarhabditis neopapillosa and an unknown Cosmocercidae species. Of the trematode infected gastropods genotyped, four species were identified, Brachylaima arcuate, Brachylaima fuscata, Brachylaima mesostoma and an unknown Plagiorchioidea species. No lungworm species were found within the city of Nottingham. To our knowledge, this study represents the first survey of gastropod-associated nematodes and trematodes in the East midlands of the United Kingdom.

Blue sharks, Prionace glauca, are cosmopolitan, extremely vagile sharks and the species among elasmobranchs for which most surveys containing tapeworm community data are available worldwide. In this study we report on the tapeworm fauna of three samples of blue sharks (n = 37) from two new regions (one sample from Galicia, north-east Atlantic, and two from Valencia, western Mediterranean), and compared it with previous studies, assessing the relative role of the ecological and evolutionary factors in structuring local tapeworm assemblages. Nine cestode taxa were identified, of which four included adult specimens, that is, Platybothrium auriculatum, Prosobothrium armigerum, Anthobothrium caseyi and Molicola horridus. The abundance of these species, and Brillouin's diversity index, differed significantly among samples without a clear geographical signal. A comparison with six previous surveys revealed that tapeworm assemblages were composed of the same ‘core’ taxa, with mean species richness typically ranging from two to four species. Global records of adult tapeworms in blue sharks included: 15 taxa identified at species level, of which only eight (generalist trypanorhynchs) were shared with other sympatric host species; five mostly with other carcharhinids; and three with large lamnid sharks sharing the blue sharks’ habitat. The composition of tapeworm communities of blue sharks is thus highly constrained by strong host specificity, with composition and abundance varying across localities depending on idiosyncratic environmental conditions.

Bisphosphonates have been proposed as pharmacological agents against parasite and cancer cell growth. The effect of these compounds on helminthic cell viability and acellular compartment morphology, however, has not yet been studied. The effects of different types of bisphosphonates, namely etidronate (EHDP), pamidronate (APD), alendronate (ABP), ibandronate (IB) and olpadronate (OPD), and their interaction with amiloride, 1,25-dihydroxycholecalciferol (D3) and proline were evaluated on a cell line derived from bovine Echinococcus granulousus protoscoleces (EGPE) that forms cystic colonies in agarose. The EGPE cell line allowed testing the effect of bisphosphonates alone and in association with other compounds that could modulate calcium apposition/deposition, and were useful in measuring the impact of these compounds on cell growth, cystic colony formation and calcium storage. Decreased cell growth and cystic colony formation were found with EHDP, IB and OPD, and increased calcium storage with EHDP only. Calcium storage in EGPE cells appeared to be sensitive to the effect of amiloride, D3 and proline. Proline decreased calcium storage and increased colony formation. Changes in calcium storage may be associated with degenerative changes of the cysts, as shown in the in vitro colony model and linked to an adenosine triphosphate (ATP) decrease. In conclusion, bisphosphonates could be suitable tempering drugs to treat cestode infections.

Podocotyle is a genus of marine opecoelid digeneans that parasitize a wide variety of fish as adults. We present the first phylogenetic analysis of several Podocotyle isolates using nuclear 28S rDNA and mitochondrial cox1 DNA regions. New sequences were obtained for Podocotyle specimens from fish caught in the Sea of Okhotsk and the White Sea. Based on morphological and molecular data, eight Podocotyle lineages of species rank were revealed. However, this diversity is poorly formalized within the current taxonomic model of the genus. As a result, we identified Podocotyle cf. angulata, Podocotyle cf. atomon, Podocotyle cf. reflexa, Podocotyle atomon of Sokolov et al., 2019, Podocotyle sp. of Denisova et al., 2023, Podocotyle sp. 1, Podocotyle sp. 2 and Podocotyle sp. 3. We also highlight the unresolved question of the life cycles of representatives of Podocotyle whose intramolluscan stages parasitize the intertidal snails Littorina spp.

Grapevine fanleaf virus (GFLV) is one of the most severe virus diseases of grapevines, causing fanleaf degeneration that is transmitted by Xiphinema index. This paper aims to isolate Xiphinema species from Tunisian vineyard soil samples and assess their ability to acquire and transmit GFLV under natural and controlled conditions. Based on morphological and morphometric analyses, Tunisian dagger nematodes were identified as X. index and Xiphinema italiae. These results were confirmed with molecular identification tools using species-specific polymerase chain reaction primers. The total RNA of GFLV was extracted from specimens of Xiphinema and amplified based on real-time polymerase chain reaction using virus-specific primers. Our results showed that X. index could acquire and transmit the viral particles of GFLV. This nepovirus was not detected in X. italiae, under natural conditions; however, under controlled conditions, this nematode was able to successfully acquire and transmit the viral particles of GFLV.

Clinostomidae is a diverse family of digenean parasitizing fish-eating birds as adults and fishes as metacercariae. The species composition, within the genus Clinostomum has been steadily increasing in recent years. In Argentina, four named species of Clinostomum have been documented, accompanied by four metacercariae representing distinct genetic lineages whose adults have not been identified. This study focused on examining clinostomids in three fish species – Australoheros scitulus (ASI), Cichlasoma dimerus (CDIM), and Pimelodella laticeps (PLA) – at various localities in Argentina. We conducted both morphological and molecular characterizations of the Clinostomum metacercariae collected from these fish species. Molecular phylogenetic analyses using COI mtDNA were performed to determine the placement of these metacercariae within the clinostomid phylogenetic tree. Clinostomum ASC represents a distinct lineage, morphologically distinguishable from other sequenced metacercariae due to its body shape (widest anteriorly and becoming slender towards the posterior end); this lineage was found to be closely related to C. caffarae. While Clinostomum CDIM and Clinostomum PLA exhibited morphological differences, they clustered together genetically with metacercariae reported in previous studies as Clinostomum L3 and Clinostomum CVI. This outcome, coupled with a low genetic distance (0 to 3%), suggests that they are conspecific with metacercariae found in fish across Mexico, Costa Rica, and Argentina. In light of the extensive diversity of fish species in Argentine freshwater ecosystems (over 500 species), and considering the relatively constrained extent of prior investigations, the anticipation of unearthing additional Clinostomum species or lineages is plausible.

The secondary response of eosinophilia has been studied in mice infected with A. suum. In mice infected orally with 1000 A. suum eggs, larvae disappeared from the body within two weeks after infection. The number of peripheral blood eosinophils decreased to the pre-infection level within eight weeks. A typical secondary response of IgG antibody production to egg antigen was found after reinfection with 1000 eggs. The number of peripheral blood eosinophils increased more rapidly after reinfection than after the primary infection. However, the peak number of eosinophils after reinfection was similar to that after primary infection, and the long-lasting characteristics of eosinophilia after reinfection did not differ from those after primary infection. These results suggest that the secondary response of eosinophilia is characterized by a rapid increase in the number of eosinophils in A. suum-reinfected mice.

Since Fasciola sp. contained proteolytic enzyme(s), it was confirmed that degradation took place in protein components in extracts of the liver flukes, which resulted in lack of clarity of sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). Degradation was shown to occur mostly during a heating process of the extract samples. The proteolytic activity in the extracts was completely blocked and electrophoretic patterns were improved only by the use of cysteine proteinase inhibitor N-[N-(L-3-trans-carboxyoxiran-2-carbonyl)-L-leucyl]-agmatine (E-64). Great improvement was also noted in electrophoretic patterns of the extracts of other trematodes, such as Paragonimus westermani, P. miyazakii and Clonorchis sinensis, when their extracts were treated with E-64.

1. A new trematode Tremajoannes buckleyi gen. et sp. nov., is described from the bats Pteronotus davyi fulvus and Mormoops megalophylla from Colombia, Central America. A comparison between Tremajoannes gen. nov. and the other related genera of the family Lecithodendriidae is given.

2. Primatotrema Premvati, 1958 is considered as a synonym of Phaneropsolus Looss, 1899, accordingly Primatotrema macacae should be Phaneropsolus macacae (Premvati, 1958), n.comb.

3. Phaneropsolus magnitesticulatus Ryšavý et al., 1960 is considered as a synonym of P. macacae (Premvati, 1958).

4. Phaneropsolus orbicularis (Diesing, 1850) Braun, 1901 is reported from a new host and redescribed.

1. A new genus and species of Isoparorchiidae Poche, 1926, is described from the air-bladder of the marine catfish, Anus jella (Val.), caught off the coast of Waltair, India. The new fluke is named Elongoparorchis pneumatis.

2. The new genus Elongoparorchis bears a superficial resemblance to the genus Isoparorchis Southwell, 1913, but differs appreciably in the structure of the testes, the ovary and the vitellaria to warrant the separation.

Rabbits were vaccinated once, by subcutaneous and intradermal injection, with sonicates of oncospheres (TpO) or conditioned media from in vitro maintained mature metacestodes (TpMcES) of Taenia pisiformis. Extracts were either incorporated into or mixed with unilammelar liposomes (reverse phase evaporative vesicles) or emulsified in Freund's Incomplete Adjuvant (FIA). Control groups received liposomes or FIA without antigen, or antigen preparation without adjuvant. Rabbits were challenged orally two weeks after vaccination with approximately 1500 eggs of T. pisiformis and necropsied eight weeks after challenge. A mean of 155 cysts was recovered from seven control rabbits. A 67% reduction in peritoneal cyst numbers was obtained in TpO–IFA vaccinated rabbits compared to 75% for the TpO–liposome entrapped group. The highest level of protection (86%) was obtained when TpO was mixed with but not entrapped in liposomes. Only 32% and 39% reduction in peritoneal cyst numbers was obtained after immunizing with the TpMcES preparation in liposomes or IFA respectively, however >85% of peritoneal metacestodes were dead (necrotic or calcified) and suggests a different immune response than occurs after vaccination with oncosphere extracts. Specific anti-oncospheral or anti-metacestode ES antibody (IgG) responses at two weeks post vaccination were similar in rabbits immunized with liposome or IFA associated extracts.

Taliaferro and Sarles (1939) who studied the cellular reaction in the skin, lung and intestine of normal and immune rats after infection with N.muris, stated that “larvae were found penetrating the skin from a half hour through two hours after they had been placed on the skin. They seemed to penetrate directly…” Yokogawa (1922) observed that this parasite when placed on the skin of rats, penetrated into the tissues very quickly. He did not specify any time for their entrance.

This paper embodies certain experiments on control of the nematode Aphelenchoides ritzema-bosi Schwartz, 1911, on chrysanthemums, and were started in September 1930 at the request of several commercial chrysanthemum growers in Staffordshire and Warwickshire.

The history of the beet-strain of Heterodera schachtii in Germany, where it was first recognized in 1859, and its subsequent discovery in other beet-growing European countries and the United States of America, have already been described in some detail in a Memorandum published by the Imperial Bureau of Agricultural Parasitology. This Memorandum was published in 1931 with the object of emphasizing the potential danger of Heterodera schachtii to the sugar-beet industry, then comparatively newly established in Britain. Observations carried out in America are quoted, which strongly indicated that the eelworm was introduced into the United States by the use of seed imported from European countries where the infection was known to be intense and of long standing; this contention, however, does not yet appear to have been decisively proved. The danger of repeated beet cultivation, without regard to rotation of crops, was particularly emphasized with reference to the wide distribution of the potato-strain of H. schachtii in Britain, and such infections as were already known to occur on other host-plants were noted.

Two species of Kalicephalus are reported from snakes. K. indicus is found to be very common in the snake, Pytas mucosus in Canton, and K. hongkongensis sp.nov. is reported for Elaphe moellendorffi.

In a large number of species of Kalicephalus examined, a telamon was always found to be present.

The genus Occipitodontus is recognised as a valid one.

Kalicephalus minutus is made the genotype of a new genus Kalicephaloides on the basis of the unequal spicules and one of the terminal branches of the dorsal ray having its origin at the base of the dorsal ray.

Third-stage and fourth-stage Dirofilaria immitis larvae exhibited positive thermotaxis when placed in a thermal gradient. Negative thermotaxis was not observed. Positive thermotaxis may be important for the successful transmission and for directing third and fourth-stage larval migration toward predilection sites in the Host.

Chemotaxonomic patterns in the distribution of amino acids of Hymenolepis palmarum (Jouri, 1956) and other hymenolepidids revealed the common presence of β-aminoisobutyric acid, lysine, phcnylalaninc and tyrosine but 3,4 dihydroxyphenylalanine and norleucine were exclusive to H. palmarum. Both qualitative and quantitative differences in amino acids have been recorded.

Using DBA/2J mice, tissue homogenates of larval Echinococcus multilocularis were injected into the mesenteric veins to generate the liver infection. Mice were treated with either albendazole or mebendazole for prolonged periods to examine the morphological changes of the metacestode. Albendazole induced disorganization of both laminated and germinal layers and suppressed the maturation of vesicles. Amorphous but loosely laminated PAS-positive material was observed inside the damaged vesicles, although new vesicles slightly developed inside or outside of the damaged ones. Active proliferation of vesicles occurred after treatment with albendazole was terminated. Hydatid cysts were more severely damaged in mice treated with mebendazole and new vesicles did not develop around the damaged ones. Also, hydatid cysts reappeared after treatment with mebendazole was terminated. These results indicate that these drugs do not eliminate larval E. multilocularis in the long-term, but mebendazole has a higher suppressive effect on multivesiculation than albendazole.