A total of 301 blue whiting, Micromesistius poutassou Risso, 1826, ranging in length from 17 to 28 cm, from Motril Bay (Mediterranean coast, south Spain) were examined for anisakid nematodes, as these fish are common items in the Spanish Mediterranean diet. Three anisakid species were morphologically identified with a total prevalence of 10.63%. Anisakis simplex s.l. Rudolphi, 1809 had a prevalence value of 6.65%, compared with 2.66% for A. physeteris Baylis, 1923 and 2.33% for Hysterothylacium aduncum Rudolphi, 1802. Variations in prevalence values with season and host size are discussed. Allozyme markers (leucine aminopeptidase-1) were used to identify anisakid nematodes assigned to the A. simplex complex and all examined larvae were found to correspond genetically to A. pegreffii Nascetti et al., 1986.

This communication reports incidental observations on Toxascaris leonina infections in a beagle breeding colony. Regular faecal monitoring demonstrated that T. leonina was endemic in the adult dam population within this colony. Small numbers of T. leonina eggs were also detected in the faeces of weaned pups from eight weeks of age possibly produced by a patent infection. This would mean a pre-patent period for T. leonina of 56 days or less. Worm counts on 10 pups showed that 60% of pups had acquired a T. leonina infection by 12 weeks of age. Since prenatal and lactogenic transmission do not occur and as the pups were kept in an environment which reduced chances of infection with T. leonina and there was no apparent source of paratenic hosts, the source of infection must have been embryonated T. leonina eggs from the whelping environment. These observations on T. leonina demonstrate that, if pups are exposed to an infected environment, patent infections may be seen in a younger age group than is normally associated with T. leonina infections.

During late summer in 1995 to 1997, repeated outbreaks of maculopapular skin eruptions were noted on the legs of children after wading in the pond in the Family Park in Laugardalur, Reykjavík, Iceland. Clinical symptoms developing on the legs resembled those of cercarial dermatitis. An examination of Lymnaea peregra snails from this pond and from the adjacent Lake Tjornin resulted in detection of previously undescribed schistosome cercariae. This is the first report of schistosomes in Iceland and also the most northern occurrence of these parasites in Europe.

This trial was conducted to evaluate the predatory activity of Duddingtonia flagrans incorporated into soy protein-based polymers as a controlled-release device (CRD). The rate of fungal release from the polymers and time of residence of the CRD in the rumen of a cannulated sheep was also determined. After administration to the sheep, the CRD was extracted at weekly intervals over a month for observation of its physical structure and faeces were collected to observe the subsequent predatory activity of the fungus in Petri dishes with water-agar 2% and Panagrellus spp. as bait. The CRD slowly degraded in the rumen over 4 weeks and liberated D. flagrans into the faeces. The formulation of the soy protein-based polymers did not affect the predatory activity of the fungus. The study demonstrates that biodegradable soy protein polymers could potentially improve the use of nematophagous fungi for controlling nematode parasites of ruminants.

The ultrastructure of the flame cells, capillaries, collecting tubes, excretory bladder, excretory atrium, caudal vesicle, lateral caudal ducts and excretory pores of cercariae of Bucephaloides gracilescens (Rudolphi, 1819) Hopkins, 1954 and Prosorhynchus squamatus Odhner, 1905 (Digenea: Bucephalidae) is described. Both species are essentially similar except for some details. The terminal parts of the protonephridia have all the structural features that are typical of trematodes. The collecting tubes in the cercarial body are composed of cells that are wrapped around the lumen. The main collecting tubes are joined to the excretory bladder syncytium by septate junctions. Features of P. squamatus excretory bladder epithelium indicate that it is involved in secretory activity, but this is not the case in B. gracilescens. In both species the luminal surface of the excretory bladder epithelium is increased by lamellae, and the basal plasma membrane forms invaginations. In the bladder syncytium of P. squamatus both apical lamellae and basal invaginations are more developed and mitochondria are also more numerous. The excretory atrium is lined by a syncytium with nucleated cytons located in the surrounding parenchyma. The atrium lining is not continuous with the body tegument and possesses specific secretory inclusions and a thick glycocalyx. Septate junctions connect the atrium syncytium to the excretory bladder epithelium at its anterior end and to the syncytial excretory epithelium lining the caudal vesicle and the lateral caudal ducts at its posterior. In the excretory pores the caudal duct syncytium is joined to the tegument by septate desmosomes.

Fasciola hepatica is the causative agent of fascioliasis, one of the most economically important helminth diseases of livestock worldwide. Traditionally, fascioliasis has been controlled by the strategic use of fasciolicidal drugs, but the emergence of resistant parasites has spurred an interest in developing vaccines as an alternative means of control. Most vaccine studies to date have evaluated conventional antigens, which are exposed to the host's immune system during the course of a natural infection. ‘Hidden’ antigens have proven to be effective vaccine candidates in other parasite species, most notably the blood-feeding nematode parasite, Haemonchus contortus, and tend to be expressed in the intestine or gut of the parasite. Fasciola hepatica is known to ingest large quantities of blood and may be vulnerable to this approach. Most, if not all, of the candidate antigens identified thus far have been membrane-bound glycoproteins which were solubilized by detergents. Here, we have attempted to employ lectins to select gut-associated glycoproteins from complex mixtures of somatic extracts of adult F. hepatica. We have conducted a comprehensive lectin-binding screen on adult histological sections with a panel of 16 fluorescently labelled lectins. Seven of the lectins bound to molecules within the gastrodermis but also bound to a range of other tissues. Within the gut tissues, jacalin and peanut lectins bound selectively to the gut lamellae and gastrodermal cells, respectively. These lectins were then used to isolate proteins from the integral membrane protein component of the adult fluke. Both lectins showed selectivity for relatively simple subsets of proteins compared to the original crude extracts.

Two groups of Galba truncatula and two groups of Lymnaea natalensis were experimentally infected with Fasciola gigantica to determine if snail species had an influence on the redial burden and cercarial shedding of this trematode when snails of both species were infected with the same isolate of miracidia. In the two groups used for the study of redial burden, the total number of free rediae was significantly higher at day 49 post-exposure in L. natalensis than in G. truncatula. In the groups used for cercarial shedding, the life-span of cercaria-shedding snails and those of infected snails which died without cercarial emission, and the duration of the prepatent period were significantly longer in L. natalensis than those noted in G. truncatula. However, the mean numbers of shed cercariae did not significantly differ and showed no differences in their daily distribution throughout the shedding period. These results demonstrate that G. truncatula might be the principal intermediate host of F. gigantica in Egypt, at least in the areas where this lymnaeid species lives.

Echinostoma revolutum eggs recovered from naturally infected wild Canada geese (Branta canadensis) were cold stored (4–6°C) for up to 72 weeks. Successful hatching followed incubation for from 6 to 8 days at an optimum temperature of between 25 and 30°C. A partial life cycle from adult worm to metacercarial encystment in Lymnaea tomentosa snails was completed in the laboratory. Snails were infected both by free miracidia and by ingestment of unhatched embryonated eggs. Infection was equally successful in environmental temperature ranges from 10 to 25°C, and at challenge levels of 2, 5 or 10 embryonated eggs per snail. Exposure to 10 eggs was lethal. Ingestion by snails of embryonated eggs with successful infection at 10°C suggests that embryonated eggs may be used to infect wild snails when the environmental water temperature has reached 10°C.

A population of a nematode species belonging to the genus Oscheius was isolated in western Uttar Pradesh, India. Morphological and morphometrical studies on this species showed its high similarity with six species described previously from Pakistan (Oscheius citri, O. cobbi, O. cynodonti, O. esculentus, O. punctatus and O. sacchari). The molecular analysis of the ITS1-5.8S-ITS2 rDNA sequences of the Indian population and the six species described from Pakistan showed that all the sequences are almost identical. Thus, based on morphological and molecular characteristics, all of the six above-mentioned Pakistani species and Indian strain do not differ from each other, hence can be considered synonyms. The correct name for this taxon is the first described species O. citri. Additionally, the phylogenetic analysis of the 18S rDNA and the 28S rDNA sequences showed that Oscheius citri is sister to the clade formed by O. chongmingensis and O. rugaoensis from China. The high similarity of morphological and morphometric characteristics of O. citri and other species, O. maqbooli, O. nadarajani, O. niazii, O. shamimi and O. siddiqii, suggest their conspecificity; however, lack of molecular data for these species does not allow this hypothesis to be tested.

We make new morphological observations not previously reported for the old acanthocephalan Macracanthorhynchus hirudinaceus (Pallas, 1781) Travassos, 1917, described for the first time about 240 years ago. Our specimens were collected from the wild boar, Sus scrofa Linn., in Ukraine in 2005. We provide comparative morphometrics with other populations from Ukraine, Union of Soviet Socialist Republics, Europe, Brazil and the United States of America. Our specimens from the Ukraine had the smallest trunk (110–120 mm long), longest and thickest hooks, with the third hook being the largest, largest eggs, and a proboscis wider than long. We document the morphology of the proboscis, apical organ, hooks, hook roots, sensory pores, micropores, and eggs with scanning electron microscopy for the first time. We also provide chemical analysis of hooks and eggs using energy-dispersive X-ray analysis, discuss its micropores, and provide a new molecular profile based on 18S rDNA from a European population for the first time. Edge of hook tips feature high levels of calcium and phosphorous but the high level of sulphur is mostly found in the cortical layer of eggs. One new partial 18S rDNA sequence (482 nt length) was generated from an adult specimen of M. hirudinaceus. We present the first 18S rDNA published sequence for this cosmopolitan acanthocephalan obtained from Europe. The amplified region corresponded to the approximate middle region of the small subunit ribosomal ribonucleic acid gene, which is ~1800 nt in length. This molecular contribution is especially valuable in light of the extreme scarcity of genetic information about species of Macracanthorhynchus and of the family Oligacanthorhynchidae as a whole.

May I say, in the first place, how highly honoured I am by the invitation of the Royal Faculty of Physicians and Surgeons of the City in which I received my early medical training to give the sixth Finlayson Memorial Lecture.

A new nematode genus and species, Paraspiralatus sakeri , is described from the stomach of a wild-caught, female saker falcon in Saudi Arabia. This spirurid differs from the nearest genus and species Spiralatus baeri Chabaud, Brygoo & Durette, 1963 in the shape of the pseudolabia, shape of the buccal capsule and absence of a large cephalic vesicle. In addition, third stage spirurid larvae were recovered for the first time from subcutaneous tissues of two houbara bustards. These had died in the Rahim Yar Khan Rehabilitation Center (Houbara Foundation International, Lahore, Pakistan) in Pakistan and were examined at the National Avian Research Center in the United Arab Emirates. The morphology of the larvae and host pathology are described. Comparative studies with the adult spirurids from the saker falcon showed each to have similar cephalic and pharyngeal morphological features to the adults described indicating they are probably the same species. Spirurid nematodes of the suborder Spirurina normally have an arthropod intermediate host. In view of the host, the site from which the larvae were recovered and the fact that this is a rare occurrence, the houbara bustard is considered to be a paratenic host.

The blue mussel Mytilus edulis is described as second intermediate host for Echinostephilla patellae from the common limpet Patella vulgata. Mussels were infected with metacercariae of E. patellae under laboratory conditions. Average infection rates increased with increasing temperature, whereas numbers of cercariae, to which individual mussels were exposed, had no effect on relative infection success. The round to slightly oval metacercariae with an average cyst diameter of 208 μm (range 186–243 μm) encysted exclusively in the foot tissue of M. edulis. Morphologically similar metacercariae were found in naturally infected mussels at sites where parasitized P. vulgata and M. edulis are sympatric. This is the first report of E. patellae in blue mussels. The detection of M. edulis being a second intermediate host is of particular interest with regard to the abundance of the parasite and host organisms in intertidal rocky shore ecosystems. The potential role of the common limpet P. vulgata as an alternative secondary host is discussed.

Hassall and Stiles (1892) described this delicate parasite and gave it the name Strongylus rubidus. Our knowledge of it has recently been increased by Hall (1921) who has shown that it is not a member of the genus Strongylus, as represented by S. equinus of the horse, but is a member of the family Trichostrongylidæ. He has created a new genus Hyostrongylus for its reception and has devoted a large part of his paper to the consideration of a male accessory organ which serves as a guide for the spicules and to which he gives the name telamon.

Laboratory-bred goldfish were experimentally infected with Contracaecum rudolphii, either directly (with nematode larvae) or indirectly via infected zooplankton. Intensity and prevalence of infection were markedly higher in fish exposed to the infected zooplankton than in goldfish exposed to nematode larvae. When transmitted to fish via the zooplankton, larvae developed much faster and, after 8 weeks, became firmly encysted in the intestine wall. The digestive tract of larvae isolated from the intestine wall showed a well-developed ventriculus, ventricular appendix and intestinal caecum. The mouth was surrounded by three lips. When free-living larvae induced infection, they rapidly penetrated the intestine wall and migrated to internal organs (e.g. liver). The primordial lips of those larvae were poorly visible, the ventricular appendix was short, and the intestinal caecum was absent. During the 10-week experiment, no encysted larvae were found in fish infected with free-living larvae.

The cestode Hymenolepis microps is an intestinal parasite of tetraonid birds, including the willow ptarmigan (Lagopus lagopus). This parasite is able to maintain a high prevalence and intensity throughout the year, even in a subarctic environment in bird populations with relatively low host densities, indicating effective transmission routes. Willow ptarmigan consume mainly vegetal material and active consumption of invertebrates is confined to the first two or three weeks of life. Ptarmigan are infected by different species of ectoparasites, of which two species of feather lice, Lagopoecus affinis and Goniodes lagopi, are the most abundant. In this study, we explored the hypothesis that feather lice may be suitable intermediate hosts for H. microps. We applied histological techniques and light microscopy to investigate lice for the presence of larval cestode stages (cysticercoids). We found 12 cysticercoid-like structures inside chewing lice collected on L. lagopus hosts harbouring H. microps. In addition, a polymerase chain reaction (PCR) screening of Ischnocera lice DNA, targeting the 18S rRNA gene of the cestode, showed positive results for two different short fragments of the 18S rRNA gene of H. microps which were sequenced from lice collected on birds. Both independent lines of evidence support the hypothesis that Ischnocera lice might be suitable intermediate hosts in the life cycle of H. microps in L. lagopus.

Urocanic acid (UCA) is known as a major chemoattractant for Strongyloides stercoralis infective third-stage larvae (L3). Since Brugia pahangi is a skin-penetrating parasitic nematode similar to S. stercoralis, UCA was expected to be a chemoattractant for B. pahangi L3. Thus, the chemoattractant activity of UCA for B. pahangi L3 was assessed. The chemotactic responses of B. pahangi L3 to UCA or acetic acid (CH3COOH) dissolved in amine solutions were assessed using an agar-plate assay. A test solution of 200 mm UCA dissolved in aqueous 270 mm tris(hydroxymethyl)aminomethane (Tris) significantly attracted B. pahangi L3 compared with deionized water (DW), while neither a solution of 200 mm UCA dissolved in aqueous 230 mm ammonia (NH3) nor 290 mm triethylamine (TEA) significantly attracted L3. Similarly, a test solution of 200 mm CH3COOH dissolved with 200 mm Tris significantly attracted L3, but neither a test solution of 200 mm CH3COOH plus 200 mm NH3 nor 200 mm TEA attracted L3. Furthermore, L3 were significantly attracted to 200 mm Tris alone, compared with DW, but avoided 200 mm NH3 and 200 mm TEA. Moreover, the chemoattractant activity of Tris for L3 was observed even at a low concentration of 25 mm, and it was observed in a mild alkaline condition but not in an acidic condition. The present study reveals that Tris is a potential chemoattractant for B. pahangi L3 while UCA is not. This finding will contribute to an understanding of the mechanisms of skin-penetrating infection of filarial L3.

Intensive cropping on a commercial scale as practised on fertile land in Europe is hitherto unknown in the Gold Coast apart from the growing of cocoa trees in a wide belt stretching from east to west across the central region of the country. In general, the method of farming is exceedingly primitive, being largely shifting cultivation, that is, the bush is partially cleared and the land is then cultivated by hand-hoes and cropped for a period of three or four years. Normally, no manure of any kind, either organic or inorganic, is applied and the land at the end of this period is allowed to revert to bush. New ground is brought into cultivation in its place, only to be allowed when virtually exhausted of readily available plant food to return to its natural, jungle condition.

Spirura hipposidcrosi n.sp. from the stomach of Hipposideros ruber resembles S. diplocyphos but differs in the head structure, the shape and size of the spicules, the position of the vulva and the presence of a tuft of spines in the male tail. Spirura nycterisi n.sp. from Nycteris thebaica and Hipposideros ruber resembles S. spinicaudata but differs in the presence of a membrane round the posterior half of the left spicule, the presence of a tuft of spines at the tip of the male tail, the position of the vulva and the size of the eggs. A key to the African species of Spirura is given.

Pear-shaped prostatic gland cells which surround the ejaculatory duct of Paramphistomum and Paradistomoides, secrete two types of products: (i) granules which are cytochemically complex containing lipids, proteins and polysaccharides (1:2, glycol groups) and (ii) globules which contain phospholipids only. The cytoplasm of these cells, in addition to high acid phosphatase activity, also contains RNA, proteins and polysaccharides.