While examining diseased sugar beet roots at the Brigg Factory of the British Sugar Corporation, Ltd., in 1936, several roots were found which were affected by the eelworm Anguillulina dipsaci (Kühn). This identification was kindly confirmed by Dr. T. Goodey.

Administration to rats of tetramisole loaded into zeolite was more successful in killing adults of Nippostrongylus brasiliensis than the administration of tetramisole alone. The most successful treatment occurred in SPF (Specific Pathogen Free) rats dosed with tetramisole loaded into zeolite and no worms were present in this group at autopsy eight days post-infection. It is concluded that the slow release of drug from the zeolite matrix improved its efficacy, especially in removing worms from low-grade infections.

Anisakis simplex larvae were cultured in vitro in medium containing 35-methionine for ten days. The medium and the larval tissues were analysed for biosynthetically labelled polypeptide by sodium dodecyl sulphate polyacrylamide gel electrophoresis and autoradiography. Immunoprecipitates with positive and negative human antisera were similarly analysed, using Staphylococcus aureus to absorb immunocomplexes. ES products of Anisakis larvae contained many polypeptides with molecular weights of less than 200 K. 180 KDa and 40 KDa polypeptides in ES products reacted with IgG in Anisakis-infected human sera. Somatic extracts also contained many polypeptides with molecular weights of less than 200 K. One of these polypeptides with a molecular weight of 130 K reacted with IgG in Anisakis-infected human sera. These polypeptides did not react with other nematode-infected human sera.

Among fish parasitic nematodes Rhabdochona is one of the most speciose genera, with c. 100 species. Twelve congeneric species occur in Mexican freshwater fishes, in a region located between the Nearctic and Neotropical biogeographical regions. Host association and biogeographical history have determined the high species richness of Rhabdochona in Mexico. One of these species, Rhabdochona mexicana, is highly specific to the characid genus Astyanax. Characids are a group of freshwater fish with Neotropical affinity. In this paper, we explore the genetic diversity of R. mexicana through samples obtained from populations of Astyanax spp. across river basins of Mexico and Guatemala. Sequences of one mitochondrial and two ribosomal genes were obtained from 38 individuals and analysed using Maximum Likelihood and Bayesian Inference analysis. Phylogenetic analyses using cox1, and a concatenated alignment of 18S + 28S + cox1 recovered two genetic lineages. One of them corresponded with R. mexicana sensu stricto; this lineage included three reciprocally monophyletic subgroups; the other lineage was highly divergent and represented a putative candidate species. A detailed morphological study was conducted to corroborate the molecular findings. We describe a new species herein and discuss the implications of using molecular tools to increase our knowledge about the diversity of a speciose genus such as Rhabdochona.

New data on the complete mitochondrial genome of Azygia robusta (Azygiidae) were obtained by the next-generation sequencing (NGS) approach. The mitochondrial DNA (mtDNA) of A. robusta had a length of 13 857 bp and included 12 protein-coding genes, two ribosomal genes, 22 transfer RNA genes, and two non-coding regions. The nucleotide sequences of the complete mitochondrial genomes of two A. robusta specimens differed from each other by 0.12 ± 0.03%. Six of 12 protein-coding genes demonstrated intraspecific variation. The difference between the nucleotide sequences of the complete mitochondrial genomes of A. robusta and Azygia hwangtsiyui was 26.95 ± 0.35%; the interspecific variation of protein-coding genes between A. robusta and A. hwangtsiyui ranged from 20.5 ± 0.9% (cox1) to 30.7 ± 1.2% (nad5). The observed gene arrangement in the mtDNA sequence of A. robusta was identical to that of A. hwangtsiyui. Codon usage and amino acid frequencies were highly similar between A. robusta and A. hwangtsiyui. The results of phylogenetic analyses based on mtDNA protein-coding regions showed that A. robusta is closely related to A. hwangtsiyui (belonging to the same suborder, Azygiida) that formed a distinct early-diverging branch relative to all other Digenea. A preliminary morphological analysis of paratypes of the two azygiid specimens studied showed visible morphological differences between them. The specimen extracted from Sakhalin taimen (Parahucho perryi) was most similar to A. robusta. Thus, we here provide the first record of a new definitive host, P. perryi, for A. robusta and also molecular characteristics of the trematode specimens.

The naturalization of alien Reeves's muntjacs (Muntiacus reevesi) on Izu-Oshima Island, Tokyo, Japan, has proceeded intensively over the last five decades. To clarify whether the gastrointestinal helminths of these animals were brought from their original endemic area or were newly acquired in Japan, 32 Reeves's muntjacs trapped on the island were parasitologically examined. In addition to Gongylonema pulchrum in the oesophagus (34.4% prevalence), Chabaudstrongylus ninhae (Dróżdż, 1967) (Trichostrongylidae: Cooperiinae) and Oesophagostomum muntiacum Jian, 1989 (Chabertiidae: Oesophagostominae) were prevalent in the small (28.1%) and large (46.9%) intestines, respectively. For the first time, these trichostrongylid or chabertiid worms were genetically characterized based on partial nucleotide sequences of the nuclear ribosomal RNA gene (rDNA) and mitochondrial DNA cytochrome c oxidase subunit 1 gene (cox-1), and the phylogenetic relationships with other members of their family were explored. Since these two intestinal nematode species are inherent in muntjacs, this study demonstrates a new distribution of exotic helminth species in Japan in accordance with the naturalization of alien mammalian hosts. The molecular genetic data collected here could assist the taxonomic assessment of morphological variants in different Muntiacus spp. and/or of different geographical origins. Furthermore, our data may help to define the phylogenetic relationships among such isolates.

The in vitro larvicidal and in vivo anthelmintic effects of Oxalis tetraphylla hydroalcoholic extract (HE), against Haemonchus contortus in experimentally infected lambs, were assessed. We used a microtitration plate method, comprising the following two stages. Stage 1: 20 μl of water containing 200 sheathed H. contortus infective larvae (ShHcl) were deposited in every well of three series; then, the series 2 and 3 wells were treated with 80 μl 1% ivermectin and O. tetraphylla HE at 20 mg/ml, respectively. Stage 2: the same procedure was performed replacing the ShHcl with exsheathed larvae (ExShHcl). Evaluations were performed after 24 and 48 h. The total numbers of dead and live larvae were counted. A second experiment evaluated the reduction in nematode egg populations in the faeces of lambs treated orally with the O. tetraphylla HE. The 27 lambs used were divided into Groups 1, 2 and 3 (n = 9), which were administered water (positive control), levamisole 1 m (7.5 mg/kg body weight (BW), as a unique dose) and O. tetraphylla HE (20 mg/kg BW), respectively. The plant HE was administered daily for 8 days. The in vitro assay showed 80.9% and 86.5% larval mortality of ShHcl after 24 and 48 h, respectively, while the corresponding mortality values for ExShHcl were 97 and 99%, respectively. The in vivo assay showed variability in the eggs/gram of faeces (epg) values; however, at the end of the trial, the average reduction in the epg values of the O. tetraphylla HE group was 45.6% (P < 0.05). Oxalis tetraphylla HE contains compounds that belong to the flavonol group with anthelmintic activity.

Chamois (Rupicapra rupicapra tatrica) in the Low Tatra National Park are largely infected with the lungworms Mullerius capillaris and M. tenuispiculatus and sporadically with Dictyocaulus viviparus. The mean number of first stage larvae (Ll) per gram of faeces collected at chamois stands over the years 1981–1988 varied between 28.2 ( ± 11.9) and 61.6 ( ± 35.9). The degree of infection in chamois herds was significantly higher in the spring and autumn months, except for the spring of 1981, than in the summer season. The mean number of Ll per gram found in the dissected chamois (lung and intestinal content) varied between 64.53 ( ± 32.7) and 97.5 ( ± 36.4).

The enzyme-linked immunosorbent assay (ELISA) and immunoelectrophoresis (IEP) were used for the serodiagnosis of larval Anisakis simplex infections in man and immunized rabbits. Sephacryl S-300 gel filtration was used for separating crude antigen. Four fractions were obtained. Sera from patients with other helminth infections sometimes cross reacted with Anisakis larval antigens. With IEP, crude antigen is more sensitive than purified antigens. With ELISA, the third fraction is the most sensitive for detecting antibodies to Anisakis larvae in the sera of humans and immunized rabbits.

Several methods for the detection of Trichinella in meat are legally prescribed in regulation (EC) No 2075/2005, which prescribes the magnetic stirrer method for pooled sample digestion (MSM) as the reference method. However, the MSM's multistage protocol requires several preparatory steps that seem to be accountable for the loss of larvae. Here we present a modified MSM (mMSM) based on: (1) an inversion of the optical path using inverse microscopy; and (2) a modified larval counting basin (mLCB, ‘Trichoview’). This enables one to examine samples of up to 40 ml and reduces the examination area from 72 to 10.3 cm2. Preparatory steps that might cause the loss of Trichinella larvae are eliminated from the new protocol. Correspondingly, the overall analytical time is reduced. In a direct and blinded comparison using 60 digest samples containing spiked vital Trichinella larvae (1–90 L1), both methods performed well for both small and large numbers of L1. However, 1278 of 1285 L1 (99.4%) were detected using the mMSM, while MSM recovered only 1225 L1 (95.3%). The improvement stems largely from samples with small numbers of L1: in all samples spiked with fewer than 10 L1, the recovery rate of mMSM was 100% compared to only 93% with MSM. Our data suggest that the use of the mMSM can improve the recovery rate by about 4% and therefore reduce the chances of a false-negative result in a sample containing 5 larvae by a factor of about 4.

Rats acquired a degree of protective immunity to reinfection with Angiostrongylus cantonensis after a single infection with 50 infective larvae. Infected rats resisted the establishment of most challenging larvae and protective immunity increased with subsequent reinfections. Part of the primary infection was lost after a superimposed second and also following a superimposed third infection, but the total size of the concurrent adult worm populations remained the same as that from a primary infection. Worms surviving from the primary infection showed enhanced growth after each reinfection but their fecundity was impaired.

Two new and one known species of Annulotrema Paperna & Thurston, 1969 are reported from the gills of the tigerfish Hydrocynus vittatus Castelnau, 1861, collected in Lake Kariba, Zimbabwe. The new species, Annulotrema pseudonili n. sp. and A. bracteatum n. sp., are described and distinguished mainly on the basis of features of the male copulatory organ (MCO). Annulotrema pseudonili n. sp. most closely resembles A. nili Paperna, 1973, but differs from it by possessing a more delicate MCO with a thin-walled base without a fibrous distal part. Annulotrema bracteatum n. sp. is most similar to Annulotrema ruahae Paperna, 1973, from which it differs by having an MCO composed of a longer copulatory tube and a leaf-shaped accessory piece enveloping the distal part of the tube. The presence of Annulotrema pikoides Guégan, Lambert & Birgi, 1988 on H. vittatus in Zimbabwe represents a new locality record for this parasite.

Antigens prepared from adult worms and microfilariae of Loa loa were used for an assessment of the sensitivity and specificity in diagnosis of double immuno-diffusion in agar gel, haemagglutination and fluorescent antibody tests.

Both antigens formed a broad band which moved slowly towards the cathode on electrophoresis, and each antigen separated into two protein fractions when passed through Sephadex G-200.

Both precipitating and non-precipitating antibodies were detected in sera from Loa loa patients. The haemagglutination test and fluorescent antibody test were sensitive in detecting Loa loa antibodies and would be of diagnostic value, but the double diffusion test in agar-gel was insensitive and would have a limited value in loiasis diagnosis.

The activity, in terms of speed of action, of three anticestode drugs against Hymenolepis nana, both in vivo and in vitro, was investigated. Praziquantel was most effective in vivo, but had little action on adult worms and cysticercoids in vitro. Niclosamide, the least effective in vivo, was highly toxic in vitro. Compound 77–6 killed adult worms and cysticercoids in vitro in 10 min and 15 min respectively at 1000 μg/ml of drug concentration, but its in viro effect was intermediate between that of praziquantel and niclosamide.

We identified and characterized the first two glutathione transferases (GSTs) isolated from juvenile cysts of Taenia crassiceps (EC 2.5.1.18). The two glutathione transferases (TcGST1 and TcGST2) were purified in a single-step protocol using glutathione (GSH)-sepharose chromatography in combination with a GSH gradient. The specific activities of TcGST1 and TcGST2 were 26 U mg−1 and 19 U mg−1, respectively, both at 25°C and pH 6.5 with 1-chloro-2,4-dinitrobenzene (CDNB) and GSH as substrates. The Km(CDNB) and Kcat(CDNB) values for TcGST1 and TcGST2 (0.86 μm and 62 s−1; 1.03 μm and 1.97 s−1, respectively) and Km(GSH) and Kcat(GSH) values for TcGST1 and TcGST2 (0.55 μm and 11.61 s−1; 0.3 μm and 32.3 s−1, respectively) were similar to those reported for mammalian and helminth GSTs. Mass spectrometry analysis showed that eight peptides from each of the two parasite transferases were a match for gi|29825896 glutathione transferase (Taenia solium), confirming that both enzymes are GSTs. The relative molecular masses were 54,000 ± 0.9 for the native enzymes and 27,500 ± 0.5 for the enzyme subunits. Thus, TcGST1 and TcGST2 are dimeric proteins. Optimal TcGST1 and TcGST2 activities were observed at pH 8.5 in the range of 20–55°C and pH 7.5 at 35–40°C, respectively. TcGST1 and TcGST2 were inhibited by cibacron blue (CB), bromosulphophthalein (BST), rose bengal (RB), indomethacin and haematin (Hm) with 50% inhibitory concentrations (IC50) in the μm range. TcGST1 was inhibited in a non-competitive manner by all tested inhibitors with the exception of indomethacin, which was uncompetitive. The discovery of these new GSTs facilitates the potential use of T. crassiceps as a model to investigate multifunctional GSTs.

0·15% of Oesophagostomum larvae fed to laboratory rats became encapsulated in the intestinal mucosa. The juvenile nematodes were able to continue their development when the infected rat tissue was eaten by pigs.

We obtained new data on the complete mitochondrial DNA (mtDNA) and the ribosomal operon of the trematode Carassotrema koreanum (Digenea: Haploporata: Haploporidae), an intestinal parasite of Carassius auratus, using next-generation sequencing. The mtDNA of C. koreanum contained 13,965 bp, including 12 protein-coding genes, two ribosomal genes, 22 transport RNA (tRNA) genes and a non-coding region. The ribosomal operon of C. koreanum was 10,644 bp in length, including ETS1 (1449 bp), 18S ribosomal RNA (rRNA) gene (1988 bp), ITS1 ribosomal DNA (rDNA) (558 bp), 5.8S rRNA gene (157 bp), ITS2 rDNA (274 bp), 28S rRNA gene (4152 bp) and ETS2 (2066 bp). Phylogenetic analysis based on mtDNA protein-coding regions showed that C. koreanum was closely related to Parasaccocoelium mugili, a species from the same suborder Haploporata. Bayesian phylogenetic tree topology was the most reliable and confirmed the validity of the Haploporata. The results of sequence cluster analysis based on codon usage bias demonstrated some agreement with the results of the phylogenetic analysis. In particular, Schistosoma spp. were differentiated from the other members of Digenea and the members of Pronocephalata were localized within the same cluster. Carassotrema koreanum and P. mugili fell within different clusters. The grouping of C. koreanum and P. mugili within the same cluster was obtained on the basis of frequencies of 13 specified codons, of which three codon pairs were degenerate. A similarity was found between two haploporid species and two Dicrocoelium spp. in the presence of TTG start codon of the mitochondrial nad5 gene. Our results confirmed the taxonomical status of the Haploporata identified in the previous studies and revealed some characteristic features of the codon usage in its representatives.

Across Far East Asia, aspermic Fasciola forms are found endemically. They have abnormal spermatogenesis and oogenesis, and it is presumed that their progeny are produced parthenogenetically and clonally. Because of this, they are also termed parthenogenic Fasciola forms. Currently, there is no evidence that they do indeed reproduce parthenogenetically and clonally. In this study, the multilocus genetic type (MLG) in 12 microsatellite markers of adult flukes and their subsequent progeny larvae were analysed using two laboratory aspermic Fasciola triploid strains. The MLGs of adults and their larvae were identical for all markers evaluated, suggesting that these strains reproduce their progeny clonally. The deviation between theoretical and actual frequency within the larvae genotype of the Fh_6 locus resulted in the inability for self-fertilization within individual adult flukes. These findings strongly suggested that aspermic Fasciola forms reproduce their progeny by means of parthenogenesis, possibly gynogenesis.

An annotated checklist of the cestode parasites of Argentinean wild birds is presented, as the result of a compilation of parasitological papers published between 1900 and April 2021. This review provides data on hosts, geographical distribution, sites of infection, location of material deposited in helminthological collections, references and taxonomic comments. A host/parasite list is also provided. During this period, 38 papers were published that gather information about 34 cestode nominal species and 11 taxa identified at generic level, belonging to three orders, ten families and 35 genera. The highest number of cestode taxa was recorded in the family Hymenolepididae, with 12 nominal species and two taxa identified at generic level, followed by Dilepididae, with eight nominal species and three taxa identified at generic level. Of the 1042 species of birds reported in Argentina, only 29 (2.8%) were reported as hosts of adult cestodes. The families of birds with the highest number of reported taxa were Laridae and Anatidae, with 20 and 14 taxa, respectively.