bluuebunny/crossref_metadata_2025 huggingface dataset:
Studies onSchistocephalus solidus
Authors: McCaig Morag L. O. , Hopkins C. Adrian
Published: June 2009

Schistocephalusplerocercoids in the weight range 2–200mg F.W. recovered from the perivisceral cavity ofGasterosteus aculeatuswere cultured in various media. In a medium composed of 25% horse serum, 0·5% yeast extract, 0·65% glucose and Hanks's saline at pH 7·1, 21°C, 95% air +5% CO2, dry weight increases of up to 500% were recorded in 8 days. Thespecificgrowth rate of large plerocercoids was only one-tenth of the rate observed in small plerocercoids. A plerocercoid of double the weight of another had approximately half thespecificgrowth rate.

Worms after 8 days cultivation were found to have only slightly higher than normal glycogen and water content, and to be able to mature when heated to 40°C. However, the rate of growth slowed to zero by the 24th day in culture at 21°C. Electron microscopic examination showed a ‘deposit’ formed over the microvilli, thin at 8 days but dense after 21 days.

Thein vivoglycogen and water content of plerocercoids from 3–300 mg F.W. was determined. Glycogen rose from 24% in plerocercoids of 10mg F. W. to 50–55% in plerocercoids over 80mg F. W. The water content was found to mimic precisely this change, falling from 82% to a plateau of 67–69%.

We wish to thank Professor Gareth Owen for permission to use the photograph shown in the Plate and for his help while using the electron microscope. It is also a pleasure to thank Miss Patricia Grant for her technical assistance.
The distribution of a primary infestation of Nippostrongylus brasiliensis in the small intestine of laboratory rats
Authors: Brambell M. R.
Published: June 2009

The small intestine of rats was divided into twenty sections in a reproducible manner in order to study the distribution of Nippostrongylus brasiliensis by stretching it under a tension of 5g in adrenaline saline.

A small but significant difference between the distribution of parasites in male and female rats was observed.

As larvae had virtually ceased to reach the intestine by the fifth day all changes in distribution after that day were due to movements of the established adult population.

Up to the twelfth day of a primary infestation the majority of the worms were found between the third and tenth sections, the population mode being in the fifth or sixth section. After the thirteenth day the number of worms in this region fell sharply.

The female worms had not ceased from egg-laying by the time most of the worms were being rejected.

The posterior half of the small intestine, i.e. the eleventh to twentieth sections, was not heavily parasitized, many of the worms seen being in passage to the anus.

The first section was not parasitized until the seventh day, but thereafter remained parasitized until long after worms had disappeared from the more posterior sections.

The relative number of male worms present increased as the infestation aged.

Throughout the experiment the relative number of male worms present at the anterior end of the smaller intestine was higher than that at the posterior.

Fourth-stage larvae were found chiefly in the sections that were later most heavily parasitized by adult worms.
The adhesive mechanism of the monogenean parasite Tetraonchus monenteron from the gills of the pike (Esox lucius)
Authors: Kearn G. C.
Published: June 2009

The monogenean parasite Tetraonchus monenteron attaches itself to the gills of the pike (Esoz lucius) by means of two pairs of large hooks (= hamuli). One pair of hooks is directed ventrally and the outer (flanking) pair is directed dorsally so that the hooks impale two adjacent secondary gill lamellage. Each lateral pair of hooks (one ventral and one dorsal hook) is operated by a single extrinsic muscle, the tendinous region of which is threaded through two fibrous loops (= Pulleys), one attached to each hook. Each tendon on entering the haptor also passes beneath transverse fibres joining the anterior ends of the two ventral hooks and these fibres probably act as a third pulley. This complex pulley system has a high mechanical advantage so that the energy used by the parasite to hold its hooks in position against the strong gill ventilating current of the host is minimal.

The mechanics of the adheasive apparatus of T. monenteron are compared with those of the monogenean gill parasite Amphibdelloides maccallumi, in, which the pulley system is less complex.

I would like to express my thanks to Mr G. W. Vane who kindly caught some pike for me, and to Dr P. C. Croghan and Mr S. A. Hodson for helpful discussion on the mechanical aspects of the adhesive apparatus.
Light and electron microscope studies of the redia ofParorchis acanthusNicoll
Authors: Rees Gwendolen
Published: June 2009

Young and old rediae ofParorchis acanthusNicoll, from the digestive gland and gonad ofNucella lapillus(L.) have been described. The young redia has an anterior collar-like fold and mid-ventral birth papilla the movements of which are controlled by a special arrangement of muscles. The birth papilla is ‘solid’ but in older rediae is replaced by a pore. The pharynx is of fairly uniform size irrespective of the size of the redia and the intestine, in the young redia, is relatively muchlarger than in the older redia which facts suggest that relatively more food may be absorbed by the mouth in the young stage. The redia cavity develops as a slit in the central cell mass. As it enlarges the intestine remains close to the dorsal wall and developing embryos are carried, among the cells, towards the surface dropping into the cavity, later, to complete their development. Up to fifty-five cercariae may be present in a redia. Simple nervous and excretory systems are present.

The tegument consists of one layer; the surface bears numerous unusual branched microvilli. The syncytial protoplasm contains numerous electron dense mitochondria, vacuoles and granules. Half-desmosomes, not recorded for any other parasitic platyhelminth, occur fairly regularly on the lower limiting layer. Below the uninterrupted basement membrane are circular and longitudinal muscles and, lining the cavity, two or three layers of flattened cells containing numerous mitochondria, agranular and granular endoplasmic reticulum and Golgi complexes. Large lipid globules accumulate in the cells.

It is suggested that, in the older redia, active transport of nutrient materials through the tegument may take place.
Taxonomic studies on Archigetes Leuckart, 1878 (Cestoda: Caryophyllaeidae)
Authors: Keneedy C. R.
Published: June 2009

Recent experimental work has indicated that species of Archigetes are capable of infecting and maturing in fishes in addition to tubificids.

The genus Archigetes is re-defined on the basis of morphological and biological characters, with particular emphasis on recent life history studies. All species capable of neotenic development have been re-united in a single genus.

A description of all species of Archigetes together with a key for their identification are included. New synonomies are discussed.

The relationship of Archigetes to other genera of the family is briefly considered, and it is concluded that it forms the terminal stage in a series showing the attainment of neotenic development.

I wish to thank Professor R. J. Pumphrey in whose Department the work was carried out, and Dr J. C. Chubb for advice and help in the preparation of this manuscript. I am also grateful to Professor K. Berg and Dr R. L. Calentine for the loan of specimens. The work was carried out during the tenure of a Nature Conservancy Research Studentship.
Structure and function in the nematode pharynx
Authors: Mapes C. J.
Published: June 2009

Pumping of the pharynx of Panagrellus has been shown to be a complex process involving three stages: the uptake of a number of globules by the corpus, the passage of the aggregate globule through the isthmus, and expulsion of the globule into the intestine by a number of pumps of the posterior bulb. It is suggested that Aplectana pumps in a similar manner to Panagrellus but at a faster rate. The pharynx of Rhabditis operated in two stages, involving the uptake of food first by the anterior half of the organ, and the subsequent passage of the ingested material through the isthmus and posterior bulb.

The pumping action of the posterior bulb suggests that the corrugated valves have a primarily valvular function. Regurgitation of intestinal contents through the pharynx is prevented by the internal pressure of the animals tending to force the walls of the organ together, and by the action of series of valves found throughout the lengths of the pharynges.

I should like to thank Professor J. E. Harris and Dr H. D. Crofton for their help during the course of this work, which was carried out during the tenure of a Postgraduate Studentship awarded by the Agricultural Research Council.
Observations on the early migration of the larvae ofAscaris suumGoeze, 1782 in white mice
Authors: Jenkins D. Conwil
Published: June 2009

The early (0–18 h) migration of the larva ofAscaris suumin the white mouse was studied.

The eggs hatched in all gut regions posterior to the stomach, the time of maximal release being between 4 and 8 h after infection. The caecum was the site of maximum larval penetration.

Penetrating second-stage larvae produced demonstrable spreading factor reaction with Evan's Blue in the mucosa of the gut. Larvae were located in the venules and lymphatics of the caecum wall as well as in the ileo-colic and hepatic portal veins. Larvae were found in the liver after 9 h and in the lungs 12 h after infection. Larvae were not seen in the muscula externa of the gut and eggs were not found in any region of the body other than the gut lumen.

A similar pattern of larval distribution was seen in the gut wall of the rat and the guinea-pig.

I am greatly indebted to Dr D. A. Erasmus for his encouragement, advice and supervision during this investigation, and also for carrying out the experimental infections. I also wish to thank Professor J. Brough for the provision of excellent laboratory facilities. Many thanks are due to Mr J. H. M. Hughes (Veterinary Officer) and the meat inspectors at Roath Abattoir who provided me with infected material. I wish to acknowledge the financial support of the Pig Industry Development Authority and the Agricultural Research Council.
A larvicidal evaluation programme using Ascaris suum in mice
Authors: Boisvenue R. J. , Hendrix J. C. , Scholz N. E.
Published: June 2009

An evaluation programme is presented for determining activity of unknown compounds on Ascaris suum larvae migrating into pulmonary tissues of animals. Data on gross lung lesions due to migrating ascarid larvae were obtained in a series of 44 screening tests consisting of 223 group observations from 1115 mice orally infected with A. suum. Lesion scores were graded in ascending order from 0 to 5 depending upon number and extent of pulmonary haemorrhages. In general, there was no significant difference in lesion scores between untreated mice and mice treated with unknown compounds in their ration. The programme is based on an initial 95% rejection of compounds with a 5% ability to retest compounds in groups of mice.

The grand mean score for 44 tests was 2·88. Ninety per cent confidence limits for means among tests established scores at 2·21 and 3·55, and among groups of mice at 1·76 and 4·00, When the test mean was less than 2·2, the ascarid ova used for infection were considered non-virulent. Compounds selected as active were in groups of mice having a mean lesion score of 1·76 or less. Banminth, Styquin and Tetramisole showed larvicidal activity. A reasonable compromise exists in this system wherein false leads are tolerated to avoid screening out effective materials. The host-parasite relationship is proposed as a valuable tool for anthelmintic evaluation.

The authors wish to thank Mr W. Henry and Mr M. Jackley of this laboratory.
The larval development of Merizocotyle sp., a monocotylid monogenean from the nasal fossae of Raia undulata
Authors: Kearn G. C.
Published: June 2009

The oncomiracidium of Merizocotyle sp., a monocotylid monogenean from the nasal fossae of Raia undulata, has 14 marginal hooklets. It seems probable that these larvae swim directly into the nasal fossae or are carried through the nostrils by the olfactory water current without first attaching themselves to the body skin. The marginal hooklets are then supplemented by a pair of hamuli and by 23 suckers, arranged in two concentric rings. The suckers arise as pockets in the ventral surface of the haptor and develop successively in a postero-anterior direction, the inner ring reaching completion before the outer ring.

I would like to express my thanks to the Director, Professor R. Weill, and to the Staff of the Station Biologique at Arcachon in France. I am grateful to the Royal Society for a Pergamon Travel Award, which enabled me to visit Arcachon.

I would also like to thank Mrs Mary Hutchinson for assistance with histological work.
Changes in adult Nippostrongylus brasiliensis during the development of immunity to this nematode in rats
Authors: Lee D. L.
Published: June 2009

Ultrastructural studies on adult Nippostrongylus brasiliensis removed at varying stages after infection from rats given a single dose of 2000 infective larvae have shown that changes in their cytology occur and that these can be correlated with the onset and development of immunity to this nematode in the host. The most noticeable changes are resorption of spermatozoa by the male reproductive tract, a drop in egg production, changes in the cytology of the intestinal cells, and the appearance of many large droplets, which look like droplets of lipid, in the cytoplasm of the hypodermis, muscles, excretory glands, reproductive system and the intestine. There are no obvious changes in the structure of the cuticle of the nematode during the course of infection. Possible reasons for the onset of these changes in the nematode are discussed.

Much of this work was carried out during the tenure of grants from the U.S. Public Health Service (grant number AI 04275) and from the Agricultural Research Council while I was working at the Molteno Institute in Cambridge. I wish to thank the late Professor J. D. Boyd and Dr C. C. D. Shute of the Department of Anatomy, Cambridge, for permission to use the electron microscopes, Mrs B. Fisher for technical assistance and Mr Paul Rogers for assistance with the photography.
Host-parasite interactions and the feeding of blood-sucking arthropods
Authors: Tatchell R. J.
Published: June 2009

The range of interactions between blood-sucking arthropods and their hosts is enormous and their importance to man would be difficult to overestimate. From the tundra to the tropics man, and animals in which he has a vital nutritional or economic interest, represent to the blood-sucking arthropod a source of animal protein. By their activities in obtaining a blood meal the host may be subjected to minimal inconvenience, acute irritation, or suffer severely from blood loss or from the effects of toxins introduced during feeding. Superimposed upon these situations is an enormous variety of disease agents which may be transmitted to the host by the parasite during or after feeding.
A new haemosporidian of lizards, Saurocytozoon tupinambi gen.nov., sp.nov., in Tupinambus nigropunctatus (Teiidae)
Authors: Lainson R. , Shaw J. J.
Published: June 2009

Saurocytozoon tupinambi gen.nov., sp.nov. (Haemosporidiidea, Leucocytozoidae) is described in the teiid lizard, Tupinambus nigropunctatus, from Pará State, Brazil. This would appear to be the first record of a member of this family in a reptile; the existing genera Leucocytozoon and Akiba are known only in birds.

The gametocytes of S. tupinambi develop within lymphocytes and immature erythrocytes. Only developing and mature gametocytes are found in the peripheral blood: morphologically they are very similar to the gametocytes of Leucocytozoon and Akiba. No mega-schizonts or other tissue stages have yet been detected.

Aedes spp., have been trapped while feeding on Tupinambus in areas where infected lizards have been caught, and may possibly be the vectors.

We are indebted to Professor P. C. C. Garnham, the London School of Hygiene and Tropical Medicine, London, who has examined our material and offered his invaluable opinions.

The cost of the colour plate was defrayed by the Wellcome Parasitology Unit, Instituto Evandro Chagas, Fundaçao Serviço Especial de Saúde Pública, Belem, Pará, Brazil.
The development of Haemonchus contortus in vitro
Authors: Mapes C. J.
Published: June 2009

The development of the exsheathed third-stage larva of Haemonchus contortus to the fourth stage in vitro has been investigated in half-strength Ringer's solution and in solutions with ionic concentrations similar to those found in the abomasum during normal secretion of acid and during heavy infestations of Haemonchus. The concentration of carbon dioxide required for the optimum development of the larva has been shown to be dependent on the pH of the medium. At a low pH the optimum pC02 is low and the larva is less sensitive to a range of carbon dioxide concentrations than at a pH near neutrality. Gastric mucin and histamine have been shown to have an inhibiting and a potentiating effect, respectively, on development, in media at pH 6.
Acquired immunity to Babesia microti and Babesia rodhaini in mice
Authors: Cox F. E. G. , Young A. S.
Published: June 2009

Mice infected with Babesia rodhaini can be cured with a single injection of Diampron and are immune to challenge with the same species. Mice infected with B. microti recover naturally from their infections and are also immune to challenge. The immunity extends to the heterologous species in both infections. In some cases parasites persist at a low level after recovery but in others the immunity is of a true sterile type. Immunity once established is unaffected by splenectomy in mice which have recovered from B. rodhaini and challenged with either B. rodhaini or B. microti.

We wish to express our thanks to May and Baker Ltd. who kindly provided us with the Diampron used in these experiments.
Demodex auratisp.nov. andD. criceti, ectoparasites of the Golden Hamster (Mesocricetus auratus)
Authors: Nutting Wm. B.
Published: June 2009

A new species,Demodex aurati, is described from the Golden Hamster,Mesocricetus auratus. It differs in both morphological detail and ecological niche fromD. cricetipresent on the same host.

When pieces of heavily parasitized skin were ‘subplanted’ for 100 days no change in morphological features of eitherD. auratiorD. cricetioccurred.

D. auratiis a low grade pathogen, apparently only harvesting the cells of the follicular epithelium.

The life cycle ofD. auratiis described.

The presence on one host species of two different species of this genus, which has affinities with demodicids of evolutionally remotely related hosts, poses an interesting problem in species specificity and ectoparasite evolution.

I wish to thank Dr Miriam Shaw, Miss Shirley DiBenedetto and Miss Helen Krause for their excellent technical help, and Dr Lawrence Bartlett and Dr Harold Rauch for perusal of the manuscript and suggestions on project procedure.

This investigation was supported by a research grant E-562 from the Institute of Allergy and Infectious Disease, of the National Institutes of Health, Public Health Service.
The structure and function of the adhesive organ in strigeid trematodes
Authors: Öhman Christina
Published: June 2009

The biology and life cycle of Apatemon gracilis minor is briefly described.

The morphology of the cup–shaped forebody with the small lappets, the pear-shaped subcuticular cells and the very flexible finger–like adhesive organ lobes is considered in some detail.

An extensive description of the body musculature is given and the mode of attachment of the parasite to the host mucosa is studied.

The main results of the histochemical tests are: (a) a relative absence of enzymes in the adhesive organ and a greater activity in the lappets; (b) the presence of two types of esterase, a non-specific esterase of B-type in the caecal cells and a non-specific esterase of resistant type, possibly a non-specific cholinesterase, in the rest of the reacting sites in the parasite; (c) a relatively small activity for leucine aminopeptidase; (d) the presence of RNA at all sites of enzyme formation; and finally, (e), the presence of enzymes and carbohydrates in the cuticle.

The activities of the parasite result in a local disruption of the host intestinal mucosa at the site of attachment. It is suggested that this is a result of the activities of the enzymes secreted by the parasite.

The absorption of nutrients and the circulatory function of the excretory system are discussed.

I should like to express my sincere thanks to Dr D. A. Erasmus for helpful discussions and advice during the progress of the work and to Professor J. Brough for giving me the opportunity to work in his department. The study was conducted during the tenure of a grant from Svenska Vetenskapliga Centralrådet i Finland.
Immunity to Trichinella spiralis
Authors: Denham D. A.
Published: June 2009

Single infections of Trichinella spiralis of 48 h duration did not produce a significant degree of immunity in mice.

Single or triple light infections of 7 h duration which, it is suggested, were composed entirely of fourth-stage larvae, did not produce significant immunity.

Single infections of 3 or 4 days duration did produce immunity. It is suggested that the fourth-stage intestinal larvae and the fourth moult are not the most important sources of immunizing antigen in a T. spiralis infection.

I would like to express my gratitude to H.M. Treasury and to the Agricultural Research Council for financial support during the time that this work was being conducted. I would also like to thank Professor W. I. B. Beveridge, within whose department this work was conducted, for the facilities provided. The helpful advice of my colleagues R. M. Connan and R. S. Phillips was of great value during the time that this manuscript was being prepared for publication.
Rhipicephalus carnivoralissp.nov. (Ixodoidea, Ixodidae) A new species of tick from East Africa
Authors: Walker Jane B.
Published: June 2009

A description is given of the male, female, nymph and larva ofRhipicephalus carnivoralissp.nov., a parasite of carnivores in East Africa, and its affinities within the genus are discussed.

Its developmental periods under laboratory conditions are given and its hosts and distribution in the field are recorded.

The author wishes to thank the Director of the East African Veterinary Research Organization for permission to publish this paper. She is also most grateful to all who made field collections of this species for her; to the British Museum (Natural History), London, for the loan of specimens from their collection; to J. P. J. Ross for the loan of specimens from his collection and to D. W. Brocklesby and K. P. Bailey, who carried out the experiments on the transmission of East Coast fever. Dr G. Theiler, Mr G. H. Yeoman, Mr G. M. Kohls, Dr C. M. Clifford and Dr H. Hoogstraal kindly checked the manuscript before publication and made helpful suggestions. Finally, she would like to thank Professor P. C. C. Garnham and Dr Charles Wilcocks for their advice on the name of this tick.
The development of resistance to glycarbylamide and 2-chloro-4-nitrobenzamide in Eimeria tenella in chicks
Authors: Ball S. J.
Published: June 2009

A twofold increase in resistance to glycarbylamide was induced in a strain of Eimeria tenella in chicks. This strain remained susceptible to amprolium, nicarbazin, nitrofurazone, zoalene, 3,5-dinitrobenzamide, 2-chloro-4-nitrobenzamide (M & B 5921) and spiramycin.

At least an eightfold resistance to 2-chloro-4-nitrobenzamide (M & B 5921) was developed in another strain of E. tenella. This strain was also resistant to nitrofurazone, zoalene and 3,5-dinitrobenzamide, but not to glycarbylamide, amprolium, nicarbazin and spiramycin.

A single test showed no transfer of drug-resistance when the two resistant strains were given simultaneously to the same birds.

When a small number of parasites of a glycarbylamide-resistant strain of E. tenella was introduced into a larger inoculum of the normal parent strain, the resistant individuals appeared to diminish in number during passages through untreated chicks.

I wish to thank Mrs B. M. Mitchell, Miss C. A. Hitchcock and Miss J. Watkins for technical assistance at various stages of the work.
The structure and development of the macrogamete and oocyst of Eimeria acervulina
Authors: Lee D. L. , Millard B. J.
Published: June 2009

The fine structure of the macrogametocyte, macrogamete and the early stages in the formation of the oocyst wall of Eimeria acervulina have been described and compared with other species of Eimeria. It has been shown that type II wall-forming bodies are formed in cisternae of the granular endoplasmic reticulum in association with Golgi complexes. The developing oocyst has been shown to be enclosed by three membranes: the outermost is the original membrane of the merozoite and macrogametocyte; the second membrane appears when the wall-forming bodies are appearing in the cytoplasm of the macrogametocyte and the innermost membrane appears after fertilization. The wall-forming bodies discharge their contents between the innermost membrane and the middle membrane.

We wish to thank Mr P. L. Long for much valuable discussion, Mrs B. Fisher for technical assistance and Mr B. Carter for assistance with the photography.
The locomotion of the acanthor ofMoniliformis dubius(Archiacanthocephala)
Authors: Whitfield P. J.
Published: June 2009

The mature egg and the acanthor ofMoniliformis dubiushave been redescribed with special emphasis on the features relevant to the locomotion of this larval acanthocephalan. The movements of acanthors have been analysed by the use of frame by frame study of filmed records of motile acanthors. Acanthors appear to use the same mode of locomotion for hatching, locomotion within the gut of the intermediate host and penetration of the host's gut wall. Movement is produced by a set of spiralled, longitudinal muscles in the body wall of the hind body and two rostellar retractor muscles. This musculature acts both directly on the body wall and indirectly by hydraulic effects via the hydrostatic skeleton of pseudocoelomic fluid. The spiny evertable rostellum and the backward facing spines of the hind body are the means whereby shape changes of the acanthor interact with the immediate environment to produce effective progression.

I should like to thank Professor D. Arthur for the provision of laboratory facilities, Dr D. W. T. Crompton for the initial gift of eggs ofM. dubiusand Mr R. D. Reed for invaluable assistance with microcinematographic technique. The work was carried out during the tenure of a Nuffield Foundation Research Fellowship.
Cytolysomes in the erythrocytes of lizards infected withPlasmodiumspp.
Authors: Scorza J. V. , Monteiro Cecilia Clara , de Scorza Cecilia
Published: June 2009

Erythrocytes ofTropidurus torquatus(Sauria, Iguanidae) infected withPlasmodium (Sauramoeba) tropidurishow acid phosphatase activity in Golgi vesicles, multivesicular bodies, secondary lysosomes and autophagic vacuoles. The functional relations between these structures and exocytotic activity is discussed.

The authors express their gratitude to: Professor A. G. E. Pearse for his helpful criticism of the work and during the preparation of the revised manuscript; to Professor P. C. C. Garnham for his advice and for his provision of facilities. We are also indebted to Mr Ian McLure for his help in translating the original Spanish into English.
Speciation and development in the genus Lagochilascaris
Authors: Sprent J. F. A.
Published: June 2009

The habitat of patients with L. minor infection in Trinidad, Tobago and Surinam is described. Three species of Lagochilascaris are redescribed and compared. A new species from Felis concolor is described and a synopsis, with a key to the genus is provided.

The development of L. minor is described from eggs and larval stages obtained from neck lesions of patients. The developmental pattern through third- and fourth-stage larvae was found to conform closely to that of other ascaridoid species, but the tail of the second-stage larva showed a unique conformation.

The earliest stage of development found in human lesions was the third stage, the smallest larva being 1·8 mm in length. The third moult was observed at about 5 mm and the fourth moult at 8 mm. Adult worms were observed with a minimum length of 5 mm in the male and 6 mm in the female. Eggs were present in some females of 8 mm length.

The observations are discussed in relation to previous concepts concerning the affinities, host specificity and evolution of this group of nematodes.

The writer takes pleasure in acknowledging the considerable help he received in this work from several colleagues and friends: Professor J. J. C. Buckley for sending specimens of L. minor and L. buckleyi from the Department of Helminthology, London School of Hygiene and Tropical Medicine; Drs A. G. Chabaud and Marie-Claude Durette from the Museum national d'Histoire naturelle, Paris for sending specimens of L. major; Dr P. Araujo from the Universidade de São Paulo, Faculdade de Farm´cia e Bioquímica for sending specimens of L. minor; Dr J. F. Teixeira de Freitas of the Instituto Oswaldo Cruz, Rio de Janeiro for sending specimens of L. turgida; Drs M. D. Little and P. C. Beaver from the Department of Tropical Medicine, Tulane University New Orleans, for sending specimens of L. minor and notes on their observations relating to L. minor. Grateful acknowledgement is also due to Dr O. H. Siung of the Ministry of Health, Port of Spain, Trinidad, and Dr Cox, Chief Medical Officer, Tobago, Dr A. H. Jonkers and his colleagues at the Trinidad Regional Virus Laboratory, and to His Excellency Dr B. F. J. Oostburg, Minister of Health of Surinam, for their considerable help and co-operation which enabled the writer to observe patients and examine specimens in Trinidad and Surinam. The able technical assistance of Miss Mary Cremin, Mrs A. McKeown and Mrs A. Green is gratefully acknowledged. Financial assistance for this study was provided under grants from the Australian Research Grants Committee, the U.S. Dept. of Health, Education and Welfare no. A. 107023–02, and the University of Queensland Research Grant.
A minimal medium for the growth ofPlasmodium knowlesiin dilution cultures
Authors: Trigg P. I. , Gutteridge W. E.
Published: June 2009

A dilution medium for the cultivationin vitroof the erythrocytic stages ofP. knowlesihas been simplified to contain the following: a balanced salt solution, glucose, isoleucine, methionine, adenosine,p-aminobenzoic acid, biotin and calcium pantothenate. The medium, in the presence of plasma gave better results than the Harvard medium for the growth ofP. knowlesiduring one asexual cycle and also allowed the subculture of the parasites through three asexual cycles before a reduction in the number of parasites was observed.

We should like to thank Dr F. Hawking and Dr K. N. Brown for their advice and Mr T. J. Scott-Finnigan for technical assistance. One of us (P.I.T.) received financial assistance from the World Health Organization.
Some aspects of nutrition in Philophthalmus burrili (Trematoda: Digenea)
Authors: Howell M. J.
Published: June 2009

The effects of P. burrili adults on the chicken host are outlined. There was no evidence that infections of up to 20 flukes caused marked pathological changes in the nictitating membrane to which flukes attach in an intimate 'placental' manner by the ventral sucker.

The food material of adult flukes is largely lacrimal secretion; it appears that blood can be excluded from the diet since the caecal contents are colourless and haemoglobin was not detected histochemically. Little material was detected in the caeca by the histochemical techniques used. The presence of a mucus coat around flukes was noted and it is suspected that materials of nutritional significance may be conserved in this coat for long periods. Glucose was demonstrated in the parenchyma surrounding the uterus. It is suggested that this might indicate either (a) polysaccharide degradation in this region; (b) polysaccharide synthesis; or (c) a site of accumulation of glucose which enters through the tegument and caeca. The presence of greatest activity in the uterine region may be indicative of nutritional dependence of the developing miracidium on the parent fluke.

The gastrodermis of the caeca is regular, consisting of flattened cells with a very prominent PAS positive, striated border of microvilli. The cytoplasm of the cells contains appreciable amounts of RNA. Protease, acid phosphatase and possibly esterase have been demonstrated in the gastrodermis.

Possible esterase activity occurs in the ventral sucker, alkaline phosphatase is present in the lining of the excretory ducts, and acid phosphatase has also been demonstrated in the pharynx, both suckers, and subcuticular region.

Ferritin was ingested by flukes in vivo and this enabled the digestion cycle to be followed. Flukes ingested little or no ferritin in vitro. Digestion was completed within 13 h and appeared to take place in close association with the striated border rather than in the lumen. The possibilities are that (a) material is digested intracellularly within the microvilli; (b) membrane (contact) digestion takes place; (c) extracellular digestion, in close association with the striated border, takes place. These processes are not necessarily mutually exclusive.

I should like to thank Professor J. D. Smyth for his helpful advice. This study was carried out during the tenure of an Australian National University Research Scholarship.
The nature of the immune response of the mouse to the bile duct cestode,Hymenolepis microstoma
Authors: Moss G. D.
Published: June 2009

The immune reaction of the mouse to the cestode,Hymenolepis microstoma, has been investigated. The mouse can carry a worm burden of up to 500 mg wet wt and there is no evidence either of rejection of the parasite by the mouse or a slowing down of growth rate of the mouse as a result of the parasite.

The nature of the antibody response has been investigated with regard to the type of antibody, onset of production, and titre.

The nature of the antibody is discussed together with the fact that there is no rejection of the parasite. The possibility that a cellular immune response might be necessary for rejection is also discussed.

I should like to express my thanks to Dr T. S. C. Orr of Fisons Research Laboratories, Loughborough, for many helpful comments and suggestions during the course of this work.

My thanks are due also to Professor C. A. Hopkins who put the facilities of the Wellcome Laboratory at my disposal at all times. My thanks, too, to Miss Gillian Moore whose technical assistance was invaluable.

The work was in part supported by a Grant from Fisons Ltd.
Short-term culture ofPlasmodium knowlesi
Authors: Butcher G. A. , Cohen S.
Published: June 2009

The culture method developed by Geiman and co-workers has been modified to give average multiplication rates forPlasmodium knowlesiof at least six-fold in 24 h.

Individual modifications have been assessed on the basis of parasite multiplication and [3H]leucine incorporation into parasite protein. The second cycle ofin vitrodevelopment which is particularly influenced by the conditions of culture was improved by: (i) culture of washed parasitized red cells in a medium containing dialysed homologous serum screened for its ability to support parasite growth; (ii) addition of ATP, Co-enzyme A (or pantothenate) and glutamine.

We thank Mr E. D. Dennis and Miss Susan Wanstall for technical assistance. This work was supported by grants from the Medical Research Council and the World Health Organization.
The effect of immunity upon some enzymes of the parasitic nematode,Nippostrongylus brasiliensis
Authors: Edwards A. J. , Burt J. S. , Ogilvie Bridget M.
Published: June 2009

Isoenzyme patterns of normal adultNippostrongylus brasiliensiswere compared with those of damaged worms permanently affected by immunity and adapted worms which show increased resistance to immunity.

Isoenzymes of acetylcholinesterase, found in glands of the head end of the worms, showed changes in damaged and adapted worms which can be related to the effects of immunity.

Aminopeptidases and non-specific esterases from the same glands were unchanged in worms affected by immunity.

Isoenzymes of acid phosphatase found in the gut of the worms were altered in damaged and adapted worms; these changes are probably secondary to the changes in acetylcholinesterases.

Of the enzymes studied, acetylcholinesterase is the enzyme most likely to be the antigen which stimulates host immunity, but final proof of this is required.

We are most grateful to Dr Valerie E. Jones for many helpful suggestions.
The feeding processes of the cattle-tickBoophilus microplus(Canestrini): A study in host-parasite relations
Authors: Moorhouse D. E. , Tatchell R. J.
Published: June 2009

The method of attachment of the cattle tickBoophilus microplus(Canestrini) has been investigated on cattle of different breeds and susceptibility to infestation.

Despite their differing sizes, the larval, nymphal and adult mouthparts penetrate to a similar depth towards the base of the Malpighian layer. Penetration may occur within 5 min of the arrival of the tick on the host.

Attachment is accomplished by the secretion of a cement substance in which the mouthparts are embedded and which adheres firmly to the hosts skin.

The cement consists of two main components: a cortex of carbohydrate-containing protein, stabilized by quinone tanning and disulphide linkages, and an internum which is lipoprotein in nature.

The start of the secretion of cement and the initial cutting of the host tissues by the chelicerae occur simultaneously. Final rapid engorgement of each stage is preceded by a secondary secretion of cement into a fluid-filled cavity which forms directly beneath the mouthparts and provides additional support.

It is concluded that attachment is an entirely mechanical process by an inert cement which does not provoke the development of host-parasite factors inimical to the tick.

It is with much pleasure that we acknowledge generous financial support by the Australian Cattle and Beef Research Committee which has made possible this project.
The route of migration of Eimeria stiedae (Lindemann, 1865) sporozoites between the duodenum and bile ducts of the rabbit
Authors: Horton R. J.
Published: June 2009

Young rabbits were infected by mouth with sporulated Eimeria stiedae oocysts and killed at 1, 3, 5, 8, 12, 16, 24, 30, 48, 54, 72, 84, and 96 h after infection. Sporozoites were found in the lamina propria of the duodenum between 5 and 8 h after infection. Sporozoites were present in the mesenteric lymph nodes, both free and within lymphatic monocytes at between 12 and 84 h after infection. No sporozoites were observed in duodenal portal blood. These observations provide morphological evidence compatible with a lymphatic route of migration between duodenum and mesenteric lymph nodes, probably within lymphatic monocytes. The route to the bile duct epithelium is discussed and a subsequent migration in the portal blood suggested.

I wish to express my gratitude to Dr D. F. Kelly of the School of Veterinary Medicine, Cambridge, for his guidance and constructive criticism, and to Dr Elaine Rose of the Houghton Poultry Research Station, St Ives, for her invaluable advice on technical problems and for donating the oocysts for the study. I should also like to thank Dr E. A. Pierce of the Department of Animal Physiology, Babraham, and Mr P. Long of Houghton for their advice.

This study was carried out as a Research Project during the Natural Sciences Tripos, Part II Pathology course 1965, in the Department of Pathology, Cambridge.
Eimeria duodenalis sp.nov. from English covert pheasants (Phasianus sp.)
Authors: Norton C. C.
Published: June 2009

A new species of coccidium E. duodenalis sp.nov., has been described, from the pheasant. It is characterized by the subspherical shape of the oocyst, the lack of polar granules and the presence of large sporocystic residual bodies. Endogenous stages are found in the epithelial cells lining the villi, and occur chiefly in the duodenum and upper intestine. Second-generation merozoites form gametocytes and/or third-generation schizonts. The prepatent period is 5 days.

E. duodenalis is moderately pathogenic, doses of 50 000 oocysts causing a 30% mortality and a significant weight loss in the survivors. Treatment with a range of sulphonamides in the drinking water was successful as was preventive treatment with Sulphaquinoxaline mixed with the food.

Acknowledgements are due to Mr S. F. M. Davies for initiating this programme and carrying out a number of the animal inoculations, to Dr Helen Hein for help and advice in the design of the experiments and to Dr L. P. Joyner for advice in the preparation of the manuscript. The author also wishes to thank Miss C. N. Hebert for the statistical analysis of weight gains and Mr M. A. Peirce, Mr G. L. Choon, Miss J. Saddington and Miss M. Blore for technical assistance.
New coccidia from Australian lizards. II. Eimeria
Authors: Cannon L. R. G.
Published: June 2009

Five new species of Eimeria are described, viz. E. ablephari from Ablepharus boutonii (Scincidae), E. egerniae from Egernia whitii (Scincidae), E. gehyrae from Gehyra variegata (Gekkonidae), E. lampropholidus from Lampropholis guichenoti and E. leiolopismatis from Leiolopisma challengeri. The characters of these species and the other coccidia from lizards are tabulated and a host check-list is given. Gall bladder parasitism is discussed as is the significance of complete sporogony occurring within the host's body. Some ideas concerning the possible events occurring in the evolution of the Haemosporina are presented.

I wish to thank Miss J. Arnold of the Zoology Department, University of Western Australia, for her identification of many of the lizards and Miss S. Curtis for her drawings. Finally I wish to thank Dr H. M. D. Hoyte, Department of Parasitology, University of Queensland, for his interest and helpful criticism of the manuscript.
Parasite vaccines versus anti-parasite drugs: rivals or running mates?
Authors: Gutteridge W. E.
Published: June 2009

Previous articles in this volume have considered the whole question of parasite vaccines from the immunological point of view. A backcloth of general concepts (Roitt, 1989) and strategies in the viral area (Schild, 1989) precedes consideration of problems specific to parasite vaccines (Mitchell, G. F. 1989). This leads on to reviews of progress to date in the development of vaccines for leishmaniasis (Modabber, 1989), malaria (Mitchell, G. H. 1989) and schistosomiasis (Sher, 1989) and in the development and use of veterinary vaccines (Morrison, 1989). I have been asked in this final chapter to take one step back from all of this and provide the alternative, chemotherapeutic, perspective. The reasons for the request are particularly pertinent, though rarely stated: antiparasite drugs already exist; if parasite vaccines are in fact developed, the way these drugs are used and the whole question of whether or not new ones are required, will have to be reconsidered. It is also a timely one: it is clear that the whole concept of a series of vaccines for the control of parasitic diseases has been so well sold, some would say oversold, that it is impacting on the resolve within the pharmaceutical industry to undertake new chemotherapeutic developments, at a time when this is already under severe strain because of financial considerations (Gutteridge, 1987 a). Hence my title: Parasite vaccines versus anti-parasite drugs: rivals or running mates?. I will try to answer it by, in turn, addressing three key questions. Why are we attempting to develop parasite vaccines? Will we be successful? If we are, will there still be a need for chemotherapy?
Biology of snail-killing flies from Africa and southern Spain (Sciomyzidae: Sepedon)
Authors: Knutson L. V. , Neff S. E. , Berg C. O.
Published: June 2009

Sepedon h. hispanica was collected in freshwater marshes in southern Spain and reared through its entire life-cycle in the laboratory.

Larvae of this species differ from those of the twenty-one other reared species of Sepedon in not normally invading water, feeding as parasitoids throughout the first half of larval life (that is, permitting their food snails to live for several days), and in restricting their diet to the genus Succinea during that time.

Each newly hatched larva of S. h. hispanica crawls between the mantle and foot of a living Succinea elegans, S. pfeifferi or S. putris and remains there while developing into or completely through the second larval instar.

After the death of the first food snail the larva becomes predatory and loses its host specificity. Then it attacks a wide range of pulmonate snails, kills each victim quickly, and destroys a series of individuals belonging to species of Succinea, Lymnaea and Physa.

Adults of S. ruficeps and S. scapularis were reared from larvae and pupae collected in Ethiopia.

The larvae of both African species are aquatic predators which kill and consume various pulmonate snails unselectively. They are equivalent ecologically to all other larvae of Sepedon previously described.

The egg, three larval instars, and puparium of S. h. hispanica, and the mature larvae and puparia of S. ruficeps and S. scapularis, are described and figured.

A key is presented to immature stages of the Palaearctic species of Sepedon.

We wish to thank Dr W. C. Frohne, Alaska Methodist University, Anchorage, Alaska for collecting and rearing Sepedon ruficeps and S. scapularis. Dr E. Morales Agacino, Instituto Espanol de Entomologia, Madrid; Dr M. Mendizabol, Dr J. Verdejo and D. J. Paris Lopez, Instituto de Acclimatacion, Almeria; and Professor Dr I. Docavo Alberti and Dr B. Llopis Minguez, University of Valencia, aided during the senior author's field-work in Spain. We thank Dr J. Verbeke, Institut royal des Sciences naturelles de Belgique, for determinations and distributional data; Mr L. W. Stratton, Harpenden, England, and Dr H. J. Walter, Dayton, Ohio, Museum of Natural History, for determinations of Gastropoda; and Mrs L. Lyneborg, Zoological Museum, Copenhagen, for Fig. 25.