Parasitism of fish in fully bunded storage reservoirs has rarely been studied, while the impact of a rapid decline in a fish population on its parasite fauna is poorly understood. The present paper investigates the helminth fauna of perch (Perca fluviatilis) over a 5-year period in the Queen Mary reservoir, a large (290 ha) completely artificial water storage impoundment, which forms a unique and challenging habitat for its resident fish population. After 3 years of study, the perch population suffered a significant reduction due to a disease outbreak caused by the pathogenic bacterium Flavobacterium columnare, ‘columnaris disease’, and the subsequent effects on the helminth fauna over the next 2 years are evaluated. Conditions in the reservoir favour the development of large populations of zooplankton, which act as intermediate hosts for the majority of helminths in the dominant perch community. The prevalence and intensity of helminth infections showed much variation over the period prior to the perch mortality. These were likely to be due to changes in the zooplankton biomass, which was exposed to biotoxins released from periodic algal blooms and the application of copper to control them. The outbreak of F. columnare resulted in a significant decrease in the size and condition coefficient of the perch population. Changes also occurred in the composition of helminth parasites, with many species demonstrating either an increase or decrease in infection levels. These changes may be partly associated with an increase in the zooplankton biomass and altered population structure, probably caused by a decrease in fish predation pressure, which would influence the parasite population dynamics, although other factors directly associated with changes in the perch population are also likely to be influential. The long-term affects on the levels of helminth infections in the fish and associated intermediate hosts in the Queen Mary reservoir are discussed.

Five critically endangered Iberian lynxes (Lynx pardinus) and 35 other sympatric carnivores (19 feral cats Felis catus, 12 Egyptian mongooses Herpestes ichneumon, and 4 common genets Genetta genetta) were analysed for helminths in Sierra Morena and Doñana area (southern Spain). Ancylostoma tubaeforme, which was believed to be harmful for lynx cubs according to a previous study, was present in the only lynx and in 53% of cats analysed in Doñana (80% in adult cats). Other species shared in both areas were Toxocara cati (1 lynx, 31% of cats), Joyeuxiella pasqualei (1 lynx, 21% of cats) and Mesocestoides sp. (2 lynxes, 5% of cats). Only one mongoose was parasitized, harbouring larvae of two acantocephalan species not previously reported in the Iberian peninsula (Centrorhynchus (Sphaerirostris) lancea and Centrorhynchus (Longirostris) undulatus). Feral cats may be a reservoir for hookworms and other helminths affecting the Iberian lynx. In contrast, mongooses and genets may not play a role in the epidemiology of these species.

A sandwich ELISA method using previously described E/S antigen-specific monoclonal antibodies has been developed to detect circulating immune complexes in patients infected with Toxocara canis. This technique could be used for the study of the dynamics of the parasite-host relationship, as we believe the detection of immune complexes and/or soluble antigen to be an improvement over detection of antibodies only. In this parasitosis, antibodies may be present in residual levels for prolonged periods after active infection.

In the following report 38 species of helminths from vertebrate hosts are considered, of which three are new. All were collected by Dr. C. Bonné of Surinam, and were presented through Prof. Leiper, F.R.S., to the London School of Tropical Medicine. The writer wishes to express his thanks to Prof. Leiper for the privilege of examining this material.

A comparative study has been made of the haptoral morphology of four species of diplozoon (Monogenea: Diplozoidae) from the gills of fish exposed to different levels of water pollution in two river systems in eastern Europe. An examination of the haptors of Paradiplozoon homoion (Bychowsky & Nagibina 1959), Paradiplozoon ergensi (Pejčoch 1968) and Paradiplozoon megan (Bychowsky & Nagibina 1959) from chub caught in the River Morava, Czech Republic and of Diplozoon paradoxum (Nordmann 1832) from bream recovered from the River Volga, Russia has revealed abnormalities to the attachment clamps. Two abnormal conditions were found: structural alterations to the attachment clamps and changes in the number of attachment clamps; these occurred both singly and in combination. A higher frequency of abnormal attachment clamps was found in diplozoons from fish caught in the more polluted localities of both rivers. The abnormalities have been recorded and their morphology compared in the light of conditions of environmental stress.

Mountain hares were collected each month between April 1984 and March 1985 and their intestines examined for helminths. 26 rabbits were also collected between Juny and December 1984 and examined for gastro-intestinal helminths. Three nematode and two cestode species were found in the hares while only two nematode and one cestode species were found in the rabbits. Trichostronglylus retortaeformis was recorded form 88% of the 193 hares and 92% of the rabbits While comparable figures for Passalurus ambiguus were 0·5% and 54% and for Mosgovoyia pectinata 14% and 81%. Seasonal fluctuations were observed in the T. retortaeformis populations in the hare; numbers tended to be low during the winter months and high throughout the summer. Paranoplocephala wimerosa was reported for the first time from the British Isles and Trichostrongylus axei was recorded for the forst time in the mountain hare.

In attempting to define the south western limits of the distribution of Schistosoma margrebowiei and S. leiperi and investigating their apparent limited distribution in relation to their snail hosts it was found that there was little overlap in the distribution of S. margrebowiei and S. leiperi and that of the human parasites S. haematobium and S. mansoni, and no overlap with S. mattheei within the area surveyed. It is suggested that the presence of either or both lechwe schistosomes prevented the development of the human parasites and in addition, prevented the development of S. mattheei in certain areas inhabited or surrounded by certain Kobus spp.

A survey of gastrointestinal helminth parasites of stray dogs (Canis familiaris) was conducted at Obollo-Afor and Ekwulobia markets, in Enugu and Anambra States, south-eastern Nigeria, respectively, to determine the patterns of infection among dogs in different parts of south-eastern Nigeria. Faecal samples collected, using long forceps, from every dog encountered in the markets between June 2007 and December 2008 were analysed by the Kato–Katz technique. Out of 413 dogs examined in both markets, 217 (52.6%) were infected with at least one of five parasites (Toxocara spp., Dipylidium caninum, Ancylostoma caninum, Taenia spp. and Trichuris vulpis). Overall faecal egg intensity of infection was 49.9 ± 58.7 eggs/g (epg). The prevalence of infection was comparable between the markets and between the male and female dogs, but varied significantly (P < 0.05) by age, decreasing from 78.9% in pups to 36.0% in adult dogs. The mean intensity pattern was similar to that of prevalence, decreasing from 86.7 ± 63.0 epg in pups to 22.1 ± 34.4 in adults. The most important individual parasite infection was Ancylostoma spp. (39.2%; 30.0 ± 41.2 epg) while T. vulpis was the least important (1.9%; 0.7 ± 5.4 epg). Generally, prevalence and intensity patterns of each parasite were also comparable between the markets and between sexes, but significantly (P < 0.05) age-dependent. The implications of these findings to public health in Nigeria and other endemic countries are discussed in relation to options for cost-effective control design and implementation.

Indirect fluorescent antibody techniques and incubation of sectioned and ligatured larvae have been used to locate the source of azocoll-positivc secretions within the oesophagcal glands of third-stage Anisakis simplex larvae. The “excretory” system, previously suggested as a source of invasive enzymes, docs not seem to be involved. The proteolytic enzyme has trypsin-like properties and evidence is presented for its continuous synthesis during in vitro storage.

In the present study we investigated two ecologically distinct populations of T. merula for the presence of helminths. We wished to determine whether urban populations of blackbirds had reduced helminth fauna compared to birds from forest habitats. Birds were caught in two ecologically distinct sites located in the eastern part of the Czech Republic. A total of 320 birds were examined. The first site was located in Prerov where the birds were obtained from a typical urban population, and the second site was Zahlinice, which constitutes a typical forest area. As a result of parasitological examination, 30 helminth species belonging to Digenea, Cestoda, Nematoda and Acanthocephala were recorded from both sites: 29 species were found in the forested site and 15 in the urban site. The overall prevalence of infection was 93.1% and differed significantly between the sites (Zahlinice 97.2%, Prerov 85.1%). The mean species richness was almost three times higher in the forest population (3.37 ± 0.10) than in the urban one (1.78 ± 0.11). The clear qualitative and quantitative differences in the helminth community of T. merula obtained from two ecologically disparate localities show that urbanization leads to a significant reduction in the helminth fauna of a bird which is highly adapted to synanthropic habitats, while still remaining common in its original forest habitat.

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.

The pumpkinseed, Lepomis gibbosus, a centrarchid fish native to eastern North America, was introduced into Europe at the end of the 19th century. Lepomis gibbosus now represents one of the most successful of introduced fish species, having spread widely throughout many European countries. In this study, we collected monogenean parasites of L. gibbosus from four sites in the Danube River Basin. We recorded four monogenean species: Gyrodactylus sp., probably acquired in the area of introduction, and Onchocleidus similis, O. dispar and Actinocleidus recurvatus, species introduced together with their host. Onchocleidus similis dominated the parasite community at all sampling sites. Actinocleidus recurvatus has only been reported from southern Europe to date and, therefore, this is the first report of A. recurvatus from Central Europe and the Danube River Basin. We observed high morphological variability in both anchor pairs of A. recurvatus. Only in O. similis was there a positive correlation observed between haptor metric traits and fish host length. Differences in metric traits between native and introduced O. similis populations may reflect a difference in fish host size, the introduced fish host achieving a smaller size than fish from native populations. A detailed analysis of microhabitat distribution indicated a preference for the second gill arch for both dominant species O. similis and A. recurvatus, with dissimilar site segregation.

The essential features of the method, which is described in detail, are a sieving technique to collect quantitatively the Fasciola hepatica eggs of a sample of cattle faeces, a new technique for transferring quantitatively the eggs to a measured amount of water, and a new technique for obtaining even distribution of the eggs within a counting chamber. Technical details for manufacturing the apparatus and the counting slide, designed to perform the different stages of the method, are given. The correctness of the resulting counts is demonstrated.

Morphometric and chaetotactic studies were carried out on the body and cephalic regions of the rediae of Fasciola hepatica (Trematoda: Fasciolidae) in order to precisely identify the different redial generations of this trematode in Lymnaea truncatula under experimental infection. At day 49 post-exposure at 20°C, the length of the redia was significantly higher in the first group of the first generation (R1a) compared with successive generations, R1b, R2a and R2b/R3a. The width of the body was similar in the R1a, R1b, and R2a rediae, but was significantly lower in the R2b/R3a groups. The intrapharyngeal cavity of R1a rediae was significantly wider compared with the R1b, R2a, and R2b/R3a groups, whereas the pharyngeal wall was significantly thicker in the R2b/R3a rediae compared with the R1b and R2a groups. Four other measurements, namely the maximum length and width of the pharynx, diameter of the mouth, and width of intestine, also showed significant variations in relation to pharyngeal morphology and age of infection. Discriminant analysis based on these measurements demonstrated that 98% of the rediae were readily categorized into the four groups identified. The number of perioral sensillae ranged from 126 to 160 but a significant difference was only noted between the mean values of the first generation and those of the group R2b/R3a. From these parameters, the maximum width of the pharyngeal lumen was found to be the best characteristic in the identification of the redial generations.

Detoxification mechanisms in parasitic helminths have not been extensively studied, despite their obvious relevance to drug development and drug resistance. Differences in detoxification enzymes between the parasite and its host may be exploitable in the design of pro-drugs, whilst selective inhibition of the parasites protective enzymes could increase their sensitivity to drug action and also make them more susceptible to the host's defence mechanisms.

1. Dipetalonema dracunculoides (Cobbold, 1870), has been found in dogs (Canis familiaris), in the Turkana District of Kenya and in a hyaena (Crocuta crocuta), in the Southern Rift Valley.

2. The dimensions of six male and six female worms agree with previous descriptions from hyaenas and dogs in Africa and from dogs in Portugal.

3. Infective larvae were found in seven out of ten Hippobosca longipennis taken from a heavily infected dog.

4. Morphologically the infective larvae are similar to those of other Dipetalonema spp., but they are much larger, averaging 2,400μ in length and 35μ in breadth with a tail length of 85μ.

5. In Africa the distribution of the parasite coincides with the distribution of H. longipennis on dogs and hyaenas.

6. This is the first time that a hippoboscid fly has been incriminated as the vector of a filarial worm. It is suggested that many other filarial species may be transmitted by Hippoboscidae.

Members of the genus Uvulifer are distributed worldwide and infect aquatic snails and freshwater fishes as first and second intermediate hosts, respectively, and fish-eating birds (kingfishers) as definitive hosts. Metacercariae of Uvulifer spp. were collected from the fins and skin of 20 species of freshwater fishes in Mexico, Guatemala, Honduras, Nicaragua and Costa Rica, and the adults were recovered from the intestine of kingfishers in four localities of Mexico. The genetic divergence among 76 samples (64 metacercariae and 12 adults) was estimated by sequencing the 28S and 5.8S nuclear genes, as well as the internal transcribed spacers ITS1 and ITS2, and one mitochondrial gene (cox1). Maximum likelihood and Bayesian inference analyses inferred with each dataset showed a high genetic diversity within the genus Uvulifer across Middle America, revealing the existence of four genetic lineages that exhibit some level of host specificity to their second intermediate hosts. The metacercariae of lineage 1 were associated with characids and cyprinids in central and northern Mexico. Metacercariae of lineages 2 and 3 were associated with cichlids distributed widely across Middle America. The lack of adults of these lineages in kingfishers, in lineages 2 and 3, or the fact that just a few adult specimens were recovered, as in lineage 1, prevented a formal description of these species. The metacercariae of lineage 4 were found in poeciliids, across a distribution range comprising Mexico, Guatemala, Honduras and Nicaragua, and the adult was found in the green kingfisher in Mexico. The number of specimens sampled for lineage 4, for both gravid adults and metacercariae, allowed us to describe a new species, Uvulifer spinatus n. sp. We describe the new species herein and we discuss briefly the genetic diversity in Uvulifer spp. and the importance of using DNA sequences to properly characterize parasite diversity.

A technique is described for the recovery of strongyloid infective larvae from bulk pasture samples. Pasture sediment washed from herbage is first concentrated, and then larvae are separated by subjecting small portions of sediment to the influence of a slow vertical current of water in a specially-designed column. A more rapid flow of water into the separation apparatus at frequent intervals agitates the sediment and releases trapped larvae into the upward flow. Several sediments can be processed simultaneously using columns arranged in parallel. Larvae separated from sediments are counted by a KI flotation technique.

A systematic review was conducted focusing on the distribution of Fasciola species and their snail intermediate hosts (IHs) in East and Southern Africa. The reviewed literature showed that both Fasciola hepatica and F. gigantica are present in East and Southern Africa, and infect a wide range of domestic and wild ruminants. Fasciola gigantica was reported in six East African and five Southern African countries, where Radix natalensis (found in low altitudes) was reported to be the main IH. Fasciola hepatica was reported in Tanzania and Ethiopia (East Africa), and in South Africa and Zimbabwe (Southern Africa), where Galba truncatula (found in high altitudes) was documented as the IH in all countries except in Zimbabwe. Both Fasciola species were documented in Tanzania, Ethiopia, Zimbabwe and South Africa. An overlap of the two was observed in areas with an intermediate altitude in Ethiopia and South Africa, where Pseudosuccinea columella was widespread and assumed to transmit both species. Pseudosuccinea columella has been reported in South Africa and Namibia, and proven to transmit F. gigantica in South Africa; its role in Namibia in the transmission of Fasciola species has not been reported. Other lymnaeid species such as R. rubiginosa were reported in South Africa, and R. auricularia in South Africa and Botswana; their role in the transmission of Fasciola species has not been proven. Future studies should aim to determine the role of P. columella in the geographical spread of the two species in East and Southern African countries.

Thirty-six helminth species were found in 324 gulls examined during June 1994 to February 1996 from different localities of Galicia: 25 trematodes (Brachylaima sp., Brachylecithum microtesticulatum, Cardiocephaloides longicollis, Cryptocotyle lingua, Cryptocotyle concavum, Diplostomum spathaceum, Echinostephilla virgula, Galactosomum phalacrocoracis, Gigantobilharzia acotylea, Gymnophallus deliciosus, Gynaecotyla longiintestinata, Himasthla elongata, Himasthla quissetensis, Knipowitschiatrema nicolai, Levinseniella (Levinseniella) propinqua, Maritrema gratiosum, Maritrema linguilla, Microphallus primas, Microphallus similis, Ornithobilharzia canaliculata, Parorchis acanthus, Phagicola minuta, Psilostomum brevicolle, Renicola sp. and Stephanoprora denticulata), four cestodes (Alcataenia micracantha, Microsomacanthus ductilis, Tetrabothrius (Oriana) erostris and Wardium cirrosa), six nematodes (Anisakis simplex, Contracaecum rudolphii, Cosmocephalus obvelatus), Eucoleus contortus, Paracuaria adunca and Tetrameres (Tetrameres) skrjabini) and one acanthocephalan (Arhythmorhynchus longicollis). Tetrabothrius erostris was the most prevalent species (79.6%), followed by C. obvelatus (47.8%), C. lingua (37.4%), G deliciosus (30.9%), G. longiintestinata (22.8%), P. adunca (21.9%), B. microtesticulatum (17.6%), E. contortus (14.5%) and M. similis (9.3%). Microphallus similis was the dominant species, with a Berger-Parker index (BP) of 0.32, followed by T. erostris (BP=0.10). All species presented an aggregated dispersion except G. acotylea and G. phalacrocoracis, which showed a random dispersion. Species that seem to have the greatest predilection for specific sites along the intestine are: C. longicollis and A. micracantha (first third), Brachylaima sp., M. similis and G. longiintestinata (last third) and A. longicollis (second half). Eight species are known to be pathogenic to commercially important fish or molluscan species and several are pathogenic to humans.