bluuebunny/crossref_metadata_2025 huggingface dataset:
Serological response of ascarid-free dogs to Toxocara canis infection
Authors: Glickman L. T. , Dubey J. P. , Winslow L. J.
Published: June 2009

Antibodies to Toxocara were measured by enzyme-linked immunosorbent assay (ELISA) in sera of ascarid-free dogs which had been fed 0,100 or 10000 embryonated T. canis eggs. Dogs fed 10000 eggs developed higher titres than those given 100 eggs and larvae failed to complete their migration to the gut. In addition, in dogs given 100 eggs, there was a significant negative correlation between the number of worms in the gut and granulomatous foci in the lung. The data suggest that the ELISA is sensitive and specific for Toxocara infection in dogs.
Effects of Ostertagia circumcincta infections on plasma gastrin in sheep
Authors: Anderson N. , Hansky J. , Titchens D. A.
Published: June 2009

Radio-immunoassay of plasma gastrin showed that hypergastrinaemia developed in sheep during experimental infections with Ostertagia circumcincta. Elevations of plasma gastrin occurred within 8 days of the first dose of infective larvae, with the most marked increase being after 11–20 days when adult worms would be expected to be present in the abomasum. Increases of plasma gastrin levels from 69·0 ± 7·6, 28·7 ± 5·3, 48·7 ± 5·9 and 60·6 ± 9·4 pg/ml before infection to maxima of 650, 230, 900 and 750 pg/ml respectively were recorded in 4 sheep infected for the first time. In 2 others which had been previously infected and then treated with anthelmintic, plasma gastrin rose from 16·0 ± 4·0 and 377 ± 87 pg/ml to maxima of 260 and 900 pg/ml at 24 and 29 days after re-infection, respectively. The cause of hypergastrinaemia has not been established. The elevation of abomasal pH which occurs in ostertagiasis may result in increased gastrin levels but is thought not to be the only cause since plasma gastrin increased before the abomasal pH rose and developed in sheep infected for a second time although their abomasal contents remained at pH 4·0 or lower. The presence of the parasite is critical for development of hypergastrinaemia as shown by return of the gastrin level to normal following therapy with an anthelmintic. It was shown that the parasites do not depend on the hypergastrinaemia since O. circumcincta became established in antrectomized sheep in which hypergastrinaemia did not develop.
A glycoprotein specific to the amphids of Meloidogyne species
Authors: Stewart G. R. , Perry R. N. , Alexander J. , Wright D. J.
Published: June 2009

Indirect immunofluorescence studies using a rabbit polyclonal antiserum have been used to localize the presence of a 32 kDa glycoprotein in the region of the amphids of 2nd-stage juveniles of the root-knot nematode, Meloidogyne incognita. Similar immunoreactivity was also demonstrated in 5 other Meloidogyne species but was not found in representatives of 8 other nematode genera including the closely related cyst nematodes (Globodera and Heterodera). Immunoelectron microscopical studies have shown that the immunoreactivity in M. incognita is associated with the secretory material filling the amphidial channel and probably with the sheath cell.
Factors contributing to the retardation of development of Obeliscoides cuniculi in rabbits
Authors: Fernando M. A. , Stockdale P. H. G. , Ashton G. C.
Published: June 2009

The relationship between the age of infective O.cunictili larvae and the proportion that remained retarded in a subsequent infection was investigated. The proportion of retarded larvae recovered was found to depend on the length of time and the temperature at which infective larvae were stored prior to infection. At 4 °C the level of retardation was found to increase with increase in the length of storage until a maximum was reached. Further storage tended to decrease the proportion of larvae that remained retarded. These effects were found to be less marked when the larvae were stored at a higher temperature. At 17 °C the maximum level of retardation reached was lower and the process of the increase and the decrease in retardation was of shorter duration. An increase in the number of larvae from 200 to 6000/rabbit did not appreciably change the proportion that remained retarded.

We are most thankful for the advice and criticisms of Dr J. D. Dunsmore. The
skilled technical assistance of Mr Ted Eaton is gratefully acknowledged. This work
was supported by the Ontario Department of Agriculture and Food.
Identification of the larvae of Hyalomma (Hyalomma) anatolicum subspecies (Ixodoidea: Ixodidae) with special reference to chaetotaxy
Authors: Snow Keith R.
Published: June 2009

An account is given of the morphological characteristics of the larvae of Hyalomma anatolicum anatolicum and H. a. excavatum. Emphasis is placed on the importance of chaetotaxy in the identification of the larvae.

I am most grateful to Professor Don R. Arthur for reading the manuscript and for his most useful advice and encouragement. Also I wish to express my sincere thanks to Dr R. P. Chaudhuri, Dr C. M. Clifford, Dr V. Dhanda, Dr H. Hoogstraal and Profesor B. Feldman-Muhsam for supplying me with specimens.
The effect ofTrichinella spiralisinfection on the mechanical properties of the mammalian diaphragm
Authors: Harwood C. L. , Young I. S. , Lee D. L. , Altringham J. D.
Published: June 2009

Trichinella spiralislarvae infect and develop within skeletal muscle cells causing major changes to their mechanical properties. The aim of this investigation was to determine the effects ofT. spiralison the power output and fatigue resistance of the mammalian diaphragm under conditions simulatingin vivooperation and to relate these to respiratory performance. Infection withT. spiralisleads to major reductions in mechanical stress, work, power output and fatigue resistance. These changes are associated with the number of larvae present in the muscle and the duration of infection. However, the initial decline in mechanical performance occurs during the onset of infection when there are few larvae observed within the muscle cells, indicating thatT. spiralismay affect the properties of muscle before encapsulation. This may correspond to the host's inflammatory response and the effects of larval excretory/secretory products. The decline in mechanical performance will have a profound effect on respiration both at rest and during exertion. This must influence the behaviour of the host and increase its chance of capture by predators, which is likely to benefit the parasite by facilitating its transmission.
Host recognition behaviour predicts host suitability in the entomopathogenic nematode Steinernema carpocapsae (Rhabditida: Steinernematidae)
Authors: Lewis E. E. , Ricci M. , Gaugler R.
Published: June 2009

Steinernema carpocapsae (Rhabditida: Steinernematidae) host recognition behaviour was assessed and compared with 2 measures of host suitability. Previous research showed that S. carpocapsae infective juveniles respond to host cues in a hierarchical order, with attraction to Galleria mellonella volatiles being stimulated by contact with G. mellonella cuticle. We measured host recognition behaviour by calculating the percentage response of S. carpocapsae infective juveniles to volatiles produced by G. mellonella last instars after the nematodes were exposed to the cuticle of 11 candidate arthropod hosts and 2 control surfaces. Host suitability was measured by nematode-induced mortality to candidate hosts at 2 nematode doses and the level of reproduction supported by each host. The highest recognition response was scored for Agrotis ipsilon (Lepidoptera: Noctuidae). This insect also incurred nearly 100% mortality due to nematode infection and supported the highest level of reproduction. Non-insect arthropods tested (Chilopoda and Isopoda) stimulated no behavioural response and were not susceptible to nematode infection. Other insect species elicited intermediate levels of the recognition response. There were significant correlations between behavioural response and nematode-induced mortality at the lower dose. The level of reproduction supported by the candidate hosts was also correlated with S. carpocapsae behavioural response.
The effect of invertebrate hormones and potential hormone inhibitors on the third larval moult of the filarial nematode, Dirofilaria immitis, in vitro
Authors: Warbrick E. V. , Barker G. C. , Rees H. H. , Howells R. E.
Published: June 2009

The effects of the insect hormones, ecdysone and 20-hydroxyecdysone, certain non-steroidal ecdysteroid agonists (RH compounds) and the inhibitor, azadirachtin, on the timing of the 3rd-stage moult of Dirofilaria immitis were investigated. 20-Hydroxyecdysone and RH 5849 when used at a concentration of 10−5 M, resulted in a premature timing of this moult. Azadiracthin, at a similar concentration, prevented moulting of most of the larvae to the 4th stage. The results are discussed in relation to the possibility of a hormonal role for ecdysteroids and neuropeptide-like compounds in the control of ecdysis in filarial nematodes, that maybe somewhat comparable to the system which is found in insects.
Experiments on the olfactory responses and host-specificity of the Oriental rat flea (Xenopsylla cheopis), (Siphonaptera: Pulicidae)
Authors: Shulov A. , Naor D.
Published: June 2009

Factors governing the response of the Oriental rat flea, X. cheopis, to the white rat and to three murids were studied in an olfactometer.

Starved females aged 5–10 days were attracted to white rats, whereas starved younger females were repelled or indifferent. Starved males, 1–10 days old, were either indifferent or were repelled.

No clear-cut attraction of 7- and 8-day-old starved females towards the murids Meriones tristrami, Acomys dimidiatus and Microtus guentheri was observed.

Starved females increased their weight during the first 8 days of life by 12·0%, while starved males lost 2·2%. Females kept in a vessel with a white rat showed a 115·2% weight gain, while males under the same conditions gained only 18·8% (Table 5).

The authors wish to thank Dr F. G. A. M. Smit, of the British Museum (Natural History), Tring, Hertfordshire (England), for his valuable help in the preparation of the manuscript for this paper.
Testosterone-induced changes in phosphatidylcholine molecular species composition ofPlasmodium chabaudi-infected erythrocytes
Authors: Fiebig S. , Simões A. P. , Wunderlich F. , Op Den Kamp J. A. F.
Published: June 2009

This study is concerned with the influence of testosterone on the phospholipid class and the phosphatidylcholine molecular species composition of various fractions obtained from the blood ofPlasmodium chabaudi-infected mice. Blood plasma, infected erythrocytes, isolated parasites and erythrocyte membranes isolated from both non-infected and infected erythrocytes in the form of ghosts were analysed. In general, the phospholipid classes remained unaffected, while the phosphatidylcholine (PC) molecular species composition showed differences after testosterone treatment. In infected erythrocytes, there was a decrease in 16:0/20:4-PC and 18:0/20:4-PC and an increase in 16:0/18:2(16:0/20:3)-PC. The decrease of 16:0/20:4-PC was exclusively confined to parasites. The rise in 16:0/18:2(16:0/20: 3)-PC and the diminution of 18:0/20:4-PC occurred in the erythrocyte membrane of both infected ghosts and non-infected ghosts as well as in the blood plasma. It is suggested that these changes occur primarily in the plasma thereby influencing the erythrocyte membranes. The decrease in 16:0/20:4-PC supports the view of the independence of the parasite from the biosynthetic lipid pathways of its host cell.
Subcellular localization of Pfs16, a Plasmodium falciparum gametocyte antigen
Authors: Baker D. A. , Daramola O. , McCrossan M. V. , Harmer J. , Targett G. A. T.
Published: June 2009

We have used immunoelectron microscopy to investigate the subcellular location of Pfs16 in Plasmodium falciparum. It was detected in the outer membrane region of gametocytes and more specifically on the parasitophorous vacuole membrane (pvm), since, during gametogenesis when the pvm disintegrates, the majority of the antigen was detected on the remains of this membrane in multilaminated whorls and not on the gamete plasma membrane. The antigen was also present on other gametocyte cellular structures, including those which we believe to be Garnham bodies, present in the host cell cytoplasm of some gametocytes. The antigen was present too on the membrane surrounding cytostomes and the resulting food vacuoles in the parasite cytoplasm.
The population age structure and reproductive biology of Gyrodactylus salaris Malmberg (Monogenea)
Authors: Harris P. D. , Jansen P. A. , Bakke T. A.
Published: June 2009

Gyrodactylus salaris has recently become a major pathogen of Atlantic Salmon (Salmo salar) in Norway. The survivorship, population age structure and pattern of insemination of G. salaris were studied to determine the extent to which this species reproduces sexually. The age-specific mortality schedule of G. salaris could be described by an exponential model but day to day variations were large, with an increase in mortality after each birth. Modelling population growth using the best fit mortality schedule indicated that, at stable age structure, 35% of the population would consist of newborn and pre-1st birth flukes. Using testis, penis and embryo development, pre-1st birth and immediately post-1st birth flukes could be unambiguously identified, and established infections were found to contain 35% pre-1st birth flukes, as predicted. The proportion of pre-1st birth flukes in newly established infections was significantly smaller, probably because of differences in the rate of transmission between newborn and older flukes. Gyrodactylus salaris is relatively long-lived, and more than 40% of the population may survive to give birth for the third time. As gyrodactylids are protogynous, and the first daughter is probably produced asexually, this long-lived strategy ensures that a large part of the G. salaris population possesses a functional male system, and that the asexually derived flukes are a smaller component of the total population in this species. Flukes with whorls of inseminated spermatozoa within the seminal receptacle were found in all age groups possessing a functional male system, and were interpreted as having been cross-inseminated. G. salaris on susceptible Norwegian salmon appears to regularly reproduce sexually, possibly accounting for its morphological variability and wide range of potential salmonid hosts.
The relationship between worm population density, host survival and the growth of the third-stage larva of Amplicaecum robertsi Sprent & Mines, 1960, in the mouse
Authors: Dobson Colin
Published: June 2009

Female mice survived longer than male mice when infected with 400 eggs but not when infected with 100 eggs of Amplicaecum robertsi.

The larvae grew to greater lengths in young than in older mice; smaller worm burdens were also found in the older animals.

The growth of the larva was associated with the total worm burden of the host. As the worm burdens, of 40-day-old female mice, increased up to 281 individuals the length of the larvae attained after 14 days decreased; when the larval population increased above this number the lengths of the worms also increased.

These crowding effects are discussed in relation to competition for nutrients, immunological suppression of larval growth and to the ability of large larval populations to swamp the resistance mechanisms of the host. It is suggested that the increased growth of the larvae in large populations is due to their ability to break down the liver of the infected host more efficiently than small populations. However, this eventually leads to the deaths of the host through total liver breakdown.

This work was done during the tenure of a Senior Research Fellowship from the Wool Research Board of Australia. My best thanks are due to Mr J. James for his assistance with the statistics, to Professor J. F. A. Sprent for his help and advice and to Mr C. Wilkinson for his assistance.
Certain aspects of the host-parasite relationship of Nematospiroides dubius (Baylis)
Authors: Dobson Colin
Published: June 2009

Adults of Nematospiroides dubius recovered from female mice were smaller than those from male mice. In general, a similar result was obtained for infections in rats. Longer worms were recovered from gonadectomized rats than from intact animals; the difference between the growth of the worms in male and female hosts was still apparent.

Treatment of castrate male rats with testosterone was more favourable to the growth of the male than the female worm. Oestradiol treatment of spayed female rats caused a stunting of both sexes of the nematode. However, this effect was least noticeable among the female worms.

An increase in the age of the rat resulted in a decrease in the lengths of the worms recovered. The worms grew to greater lengths in 25-day-old mice than in rats of the same age and sex.

It is suggested that the sex hormones may have two effects on worm growth. First, an indirect effect involving the nutrition of the worm, and secondly, a direct effect of the hormones themselves on the tissues of the worm.

This work was done during the tenure of a Department of Scientific and Industrial Research Studentship. My thanks are due to Dr E. T. B. Francis for his help and criticism, and to Professor I. Chester Jones, in whose department the work was done, for the facilities he provided.
The effects of pregnancy and treatment with progesterone on the host–parasite relationship of Amplicaecum robertsi Sprent & Mines, 1960, in the mouse
Authors: Dobson Colin
Published: June 2009

Male mice harboured more third-stage larvae of Amplicaecum robertsi than females; these larvae also grew longer than did those in female mice. Gonadectomy removed the differences, evident between the sexes, in both the numbers recovered and the growth of the third-stage larva, between male and female mice. The worms recovered from the gonadectomized hosts were smaller than those from the intact male and female host.

Pregnant female mice harboured more worms than either the male or the non-pregnant female mouse. These worms were also smaller than those from the male and non-pregnant females. There was no difference in the growth of the larvae from gonadectomized and pregnant hosts.

The treatment of spayed female mice with progesterone resulted in an increase in the size of worm population as compared with the numbers of worms recovered from intact female mice. The worms from the progesterone-treated spayed females were also longer than those from the spayed female hosts.

Treatment of normal female mice with progesterone resulted in an increased recovery of worms compared with the numbers of worms recovered from normal female animals. The worms were stunted but they were of a size comparable to those recovered from pregnant female mice.

It is suggested that the increase in the size of worm populations and the stunting of the worms recovered from pregnant female mice is associated with the effects of progesterone in relation to the hormone balance associated with the ovary at the time of pregnancy.
The attachment of the monogeneanDiplectanum aequans(Wagener) Diesing to the gills ofMorone labraxL.
Authors: Paling J. E.
Published: June 2009

The main adhesive apparatus ofDiplectanum aequansis described and a functional interpretation is offered.

Two sets of organs are involved in adult animals: 4 hamuli (median hooks) and the 3 associated accessory bars, and 2 squamodiscs.

The two pairs of hamuli are ‘gaffed’ into the gill tissue of the host by the following mechanism: muscular contraction produces a posterior movement of the anterior ends of the hamuli which are so pivoted that the points of the hamuli are caused to extend out from the haptor.

The squamodiscs of adults are operated by extrinsic muscles which produce posterior movement in the anterior region of each squamodisc. This tends to push the parasite out from its position between adjacent secondary gill lamellae.

The tendency to dislodgement is opposed by the two pairs of hamuli which ‘gaff’ into the base of the secondary lamellae. In addition, the more posterior spines on the squamodiscs become embedded in the gill tissue and so provide further resistance to the movement of the anterior region of the squamodisc. Thus the attachment of adults requires both sets of adhesive organs functioning in a complementary manner.

Juveniles do not possess squamodiscs. They are considered to adhere to their hosts primarily with their hamuli.

I would like to acknowledge the help given to me by the Director and Staff of the Marine Biological Association Laboratory and also the Proprietors of Cook and Sons Ltd., of Salcombe, Devon.
Fasciola tragelaphisp.nov. from the sitatunga,Tragelaphus spekeiRothschild, with a note on the prepharyngeal pouch in the genusFasciolaL.
Authors: Pike A. W. , Condy J. B.
Published: June 2009

Fasciola tragelaphisp.nov. from the bile ducts of aTragelaphus spekeishot in the Chobe swamps of Rhodesia differs from other species of the genus in its very large size (10.2–12.0 cm long in fixed and mounted specimens), in the shape of its body and in the distribution and arrangement of the reproductive organs. The testes lie almost entirely in the posterior half of the body, well away from the female genitalia, which lie mostly in the anterior third of the worm. The ovary is always bilateral, and the coiled uterus runs in a straight line between the caeca to the genital atrium. A prepharyngeal pouch found in this species is compared with that found in other members of the genusFasciolaand in related genera.

We gratefully acknowledge the help given during the preparation of this paper by the staff of the Bureau, particularly Mr G. Dimmock for technical assistance. We would also like to thank Mr S. Prudhoe for reading the manuscript and offering useful advice, Mr B. Bracegirdle for producing the photograph of the whole worm reproduced in the Plate, fig. 1 and to Bechuanaland Hunters Ltd., particularly I. M. Henderson, for obtaining further specimens for examination.
Oviposition in Hyalomma anatolicum anatolicum (Koch, 1844) (Ixodoidea: Ixodidae)
Authors: Snow K. R. , Arthur Don. R.
Published: June 2009

For the tick Hyalomma anatolicum anatolicum, at constant temperature and humidity, the pattern of oviposition is constant, and consists of a peak period, usually after 2–3 days, followed by a gradual decline.

Oviposition proceeds more rapidly in constant darkness than in continuous light.

With increased temperature the oviposition period is decreased, but with increased humidity the period is extended.

The largest eggs are laid from 0 to 48 h after the peak of egg production, and no correlation has been observed between female size and egg size.

The number of eggs produced by a tick is directly proportional to its engorged weight, and since the engorged female weight is a direct reflexion of its unfed weight, the number of eggs laid is directly dependent on the size of the unfed female.

Guinea-pigs show partial immune response to adults of H. anatolicum anatolicum when the ticks are fed on them repeatedly. This minimizes the amount of nutrients imbibed and accordingly egg-laying potential is not realized.

The material on which this study was made was presented to us by Dr R. P. Chaudhuri, and we gratefully acknowledge his kindness.
Evagination of the cysticercoid inPolycercus lumbrici
Authors: Scott J. S.
Published: June 2009

A number of experiments was carried out onPolycercus lumbricito induce evagination of the cysticercoidin vitro. The results indicate that in nature the containing cyst is ruptured by pressure and abrasion in the gizzard of the bird host and that evagination is induced mainly by the action of gastric juice followed by pancreatic juice, heat assisting the process by exciting vigorous movements in the larvae. By a process of elimination it has been shown that the effective agents are the pepsin in the gastric juice and pancreatin in the pancreatic juice. The latter probably causes contraction of the muscles of the wall of the caudal vesicle which forces out the scolex.
Perezia helminthorum sp.nov., a microsporidian hyperparasite of trematode larvae from Malaysian snails
Authors: Canning Elizabeth U. , Basch Paul F.
Published: June 2009

Amongst parasitic platyhelminthes three Microsporidia are named from cestodes and seven from trematodes. Those in cestodes are Nosema helminthorum Moniez, 1887, Glugea ghigii Guyenot & Naville, 1924 (= Nosema (Plistophora) ghigii Guyenot, Naville & Ponse, 1925) and Stempellia moniezi Jones, 1942. Those in trematodes are Nosema distomi Lutz & Spendore, 1908, Nosema legeri Dollfus, 1912, Nosema echinostomi Brumpt, 1922, Nosema (Plistophora) spelotremae Guyenot, Naville & Ponse, 1925, Glugea encyclometrae Guyenot & Naville, 1924 (= Nosema (Plistophora) encyclometrae Guyenot, Naville & Ponse, 1925), Glugea ghigii Guyenot, Naville & Ponse, 1924 (= Nosema (Plistophora) ghigii Guyenot, Naville & Ponse, 1925) and Nosema dollfusi Sprague, 1964. Other species are recorded but not named.
Histochemical demonstration of aminopeptidase activity associated with the intramolluscan stages ofPhilophthalmus gralliMathis & Léger
Authors: Cheng Thomas C. , Yee Herbert W. F.
Published: June 2009

Third-generation rediae and escaped cercariae ofPhilophthalmus gralliare found primarily in the interacinar spaces on the periphery of the hepatopancreas of its molluscan host,Tarebia granifera. The presence of these stages ofP. grallicauses both mechanical and physiological damage to the adjacent host cells. Mechanical damage results from ingestion by rediae and pressure exerted by motile rediae and cercariae. Histochemical tests involving two different substrates L-leucyl-α-naphthylamide and L-leucyl-4-methoxy-β-naphthylamide, have revealed the occurrence of aminopeptidase activity associated with the body surfaces of both rediae and cercariae. This exopeptidase is believed to be responsible for the lysis of the cytoplasm of surrounding host cells during migration and to be associated with extracaecal digestion. The intensity of the enzyme activity is correlated with the ages of the rediae and cercariae. Young rediae did not reveal aminopeptidase activity and cercariae within redial brood chambers revealed little or no activity.

This research was supported in part by a grant from the American Cancer Society.
Habronematinae (Nematoda: Spiruridae) from Australian birds
Authors: Mawson Patricia M.
Published: June 2009

A list is given of all habroneme species recorded from Australian birds, as well as a key to all known genera of Habronematinae. New species described are: Cyrnea (Procyrnea) dollfusi from Ninox novaeseelandiae; Cyrnea (Procyrnea) falco from Falco longipennis and F. berigora; Cyrnea (Procyrnea) spiralis from Philemon argenticeps, Entomyzon cyanotis, Oriolus sagittatus and Lalage sueuriitricolor; Excisa biloba from Podargus strigoides, Ninox novaeseelandia; Viguiera longicollis from Colluricinda rufiventris, C. harmonica, Anthochaera carunculata and Microeca fascinans; V. chibiae from Chibia bracteata; V. chabaudi from Podargus strigoides. Partial redescriptions are given of Cyrnea (Procyrnea) paraleptoptera (Johnson & Mawson) from the type specimens; Cyrnea (Procyrnea) mansioni from Falco berigora, Haliastur sphenurus, Astur novaehollandiae, and a ‘hawk’; Cyrnea (Procyrnea) sp. from a parrot, Psephotus haematonotus; Hadjelia truncata from Eurystomus orientalis; Hadjelia acuariana (s. Stellabronema acuariana Gushans-kaya) from Podargus strigoides; Torquatella balanocephala from Merops ornatus, and Torquatella sp. from Centropus phasianus.
A gigantic Protostrongylus, P. africanus sp.nov., and other lung nematodes of antelopes in the Serengeti, Tanzania
Authors: Dinnik J. A. , Sachs R.
Published: June 2009

It was found that antelopes in the Serengeti area, Tanzania, East Africa, are heavily infested with lung nematodes. Five species of the family Protostrongylidae, namely, Protostrongylus africanus sp.nov., P. etoshai Ortlepp, P. gazellae Yeh, Pneumostrongylus calcaratus Mönnig and P. cornigerus Ortlepp, as well as one species of the family Dictyocaulidae, Dictycaulus viviparus (Bloch), were recorded.

A detailed description of Protostrongylus africanus sp.nov., which is conspicuous for its gigantic size, is given, and the lesions caused by this lung nematode are described.

The distribution and incidence of lung nematodes in the various antelope species are discussed.
Chevreuxia americana sp.nov. (Nematoda: Acuariidae) from the avocet, Recurvirostra americana, in Colorado
Authors: Schmidt Gerald D.
Published: June 2009

Chevreuxia americana sp.nov. is described from the gizzard of the avocet, Recurvirostra americana, in Colorado. It is compared with the four previously described species in the genus.
Chromosomes of the tsetse fly, Glossina palpalis R.-D.
Authors: Riordan K.
Published: June 2009

Mitotic metaphase chromosomes of the tsetse fly Glossina palpalis R.-D. have been investigated.

The chromosomes studied were in circumoesophageal nervous tissue from young pupae, stained with aceto-orcein and spread by squashing.

The diploid number of chromosomes was shown to be 6, consisting of 2 long pairs and 1 short pair at metaphase.

This finding is discussed briefly in relation to previous descriptions of the chromosomes of G. tachinoides West. and G. morsitans morsitans West. and to accepted systematic divisions of the genus Glossina into subgeneric groups.

I wish to thank Mr H. Dickson for assistance with photography. I thank Mr D. A. T. Baldry for advice and suggestions concerning the manuscript. Mr T. M. Leach has also made suggestions concerning the manuscript, and as Director of the Nigerian Institute for Trypanosomiasis Research, has given his permission to publish this paper.
Serological and morphological studies on the inter- and intraspecific differences of the plant-parasitic nematodes Heterodera and Ditylenchus
Authors: Webster J. M. , Hooper D. J.
Published: June 2009

Saline extracts of species of Ditylenchus and Heterodera initiated antibody production when inoculated separately into rabbits. On agar gel-diffusion plates these antisera gave a precipitate response against their homologous extracts and against extracts of some of the other nematode species. Up to four precipitation bands occurred, indicating the presence of at least four distinct antigens. Antisera to these extracts did not precipitate against extracts of the host plant or against the extracts of nematodes from other genera. None of the nematode extracts precipitated against normal serum. The precipitation response divided the Heterodera species tested into two groups, one containing H. schachtii, H. trifolii and H. rostochiensis and the other containing H. cruciferae, H. carotae and H. goettingiana with apparently no antigens common to both groups. The three species of Ditylenchus were serologically distinct, and it was not possible to interbreed D. myceliophagus and D. destructor. The extent of the postvulval sac was the most useful morphological character for separating D. myceliophagus from D. destructor. Only slight intraspecific serological differences were detected between five races (narcissus, oat, red clover, tulip and giant) of D. dipsaci and between the two pathotype populations (Colyton and Woburn) of H. rostochiensis. Precipitates occurred at the excretory pore of living larvae and adults of Ditylenchus species and at the vulval aperture of white females of Heterodera species placed in their homologous antisera.

We thank Dr A. J. Gibbs for much advice.
Ixodes pacificusCooley and Kohls, 1943: Its life-history and occurrence
Authors: Arthur Don. R. , Snow Keith R.
Published: June 2009

The life-history ofI. pacificuswhen fed on guinea-pigs under laboratory conditions is described. Feeding of the female proceeds for 10–11 days. Between 120 and 191 mg of concentrated food is found in the female's gut on detaching from this host, and this is directly related to the unfed body weight of the tick.

The egg-laying pattern, in general, shows an initial peak, after which the number of eggs tails off, the whole process lasting approximately 33–40 days. The number of eggs laid by females varies between 790 and 1300. The preoviposition period is about 11–16 days.

Larvae hatch in about 53–55 days, and their feeding time ranges from 4 to 9 days, although in the present experiments larvae emerging from early laid eggs took about 10 days to complete engorgements.

Moulting of larvae to nymphs at 90% R.H. took 37–38 days, and nymphs fed for 7–11 days, with most becoming replete on the ninth.

Very few females emerged from these nymphs, and those that did emerged in just over 30 days. The reasons for this are not clear. No diapause appeared to be necessary to complete the life-cycle, and with due allowance for hardening of the mouthparts the life-history of one generation was about 7 months. Females died within 3 or 4 months if hosts were not available.

From the literature and from hitherto unpublished records some 55 vertebrates have been implicated as hosts toI. pacificus;these hosts include a wide range of mammals, six species of birds and possibly nine species of lizards.

The species has been listed from British Columbia and from five western states of U.S.A. The need for more intensive ecological work on this species is emphasized.

We are indebted to Glen M. Kohls, J. D. Gregson and D. E. Johnstone for permission to use unpublished records from their respective institutions. One of us (D.R.A) is also indebted to the Wellcome Trustees for financial assistance to visit Canada during the preliminary stages of the work.
Ultrastructural studies on the sporozoite of Eimeria tenella
Authors: Ryley John F.
Published: June 2009

The structure of the sporozoite of Eimeria tenella has been studied with the aid of the electron microscope, using both sectioned fixed material and negatively stained or shadowed whole cells. An apical ring gives rise to a series of 24 fibrils which extend posteriorly under a double bilamellar membrane. Within the apical ring lies a conoid with spirally arranged tubules and an apical pore; under some conditions at least this conoid can be pushed forward beyond the apical ring. Originating within the conoid are a group of club-shaped organelles which extend backwards into the cell to lie among an extensive regular array of micronemes. The nucleus lies between two apparently structureless paranuclear bodies, and scattered throughout the remaining cytoplasm are mitochondria with tubular cristae, oval structures containing amylopectin, occasional lipid droplets, and vesicles containing nondescript material possibly undergoing digestion and which may have a possible connexion with a lateral micropyle.

I am indebted to Mrs Muriel Bentley for much technical collaboration and to Mrs McLaren for making her manuscript available before publication.
Studies of the amino acids ofRhodnius prolixus. II. Analysis of the excretory material
Authors: Harington J. S.
Published: June 2009

1. A qualitative paper chromatographic analysis of the free amino acids inRhodniusurine and excreta was made: eleven amino acids or related compounds were detected, cystine and cysteic acid in urine, and histidine, histamine, leucine, taurine, glycine, valine, phenylalanine and alanine in the excretory fractions.

2. In addition to these, three yellow pigment spots were separated from the excreta; one of these is of unknown composition and two are peptides.

3. A possible relationship between certain of the excretory amino acids and haemolymph ones is discussed.

I am greatly indebted to the late Professor P. A. Buxton, C.M.G., F.R.S., for his stimulating criticism during this study, and to the members of the School for very useful discussion, and to Mr Paul Baily for performing the column chromatographic analyses on my behalf. The study forms part of a Thesis for the degree of Ph.D. approved by the University of London, and was financed by the South African Council for Scientific and Industrial Research. I wish to acknowledge their generous financial support.
The effect of the miteMyocoptes musculinus(C. L. Koch 1840) on the skin of the white laboratory mouse and its control
Authors: Watson D. P.
Published: June 2009

1. The means of attachment of the miteMyocoptes musculinusto the hair of the host, the mouse, and the sites where it is located are given.

2. Normal and skin infected withM. musculinusof young (6–8 weeks) and adult (6 months) mice is treated with colchicine and examined histologically.

3. Infected skin shows a mitotic count of approximately four times that of normal skin in the adult; there is no appreciable difference in the young.

4. Acaricides used to control the mite were benzene hexachloride (0·015%), dieldrin (0·015%), arsenic and sulphur mixture (0·018% arsenic), piperonyl butoxide (5%) and dimethylphthalate (100%); the latter being the most efficacious.

5. It is established that the drugs had no effect on the rate of division of the cells of the malpighian layer of the skin.

6. The number ofMyobiapresent increases as theMyocoptesare killed unless dimethylphthalate, an oily liquid, is used at intervals.

7. Diet in conjunction with signs of mange is discussed.

8. Carriers ofM. musculinusare given.

I wish to thank Cooper McDougall for supplying the materials used in dipping and swabbing, and the Infestation Control Laboratory of the Ministry of Agriculture for supplying me with a number of specimens of wild mice from different parts of the country. I am also grateful to the Council of the Royal Free Hospital School of Medicine for facilities for carrying out the work; and to Dr A. M. Hughes for her helpful guidance at all stages of the work and especially for reading the paper.
Histochemistry of Hymenolepis microstoma (Cestoda: Hymenolepididae)
Authors: Bogitsh Burton J. , Nunnally David A.
Published: June 2009

Reduction of neotetrazolium in the presence of succinate is used as a quantitative assay for succinic dehydrogenase activity in homogenates of Hymenolepis microstoma, and nitro blue tetrazolium and thiazolyl blue tetrazolium-cobalt are employed with cryostat sections for its histochemical localization in adults and cysticercoids. The highest concentrations of the enzyme occur in the anterior region of the worm (scolex, neck, and immature proglottids), lesser amounts in the region of mature and early gravid segments, and least amounts in the gravid region of the strobila. Primary sites of succinic dehydrogenase activity are the mitochondrial layer of the cuticle and the cells of the subcuticle. In the anterior region the entire parenchyma shows uniformly high concentrations of enzyme activity. This reaction decreases posteriorly until, in the gravid region, only the subcuticle and the mitochondrial layer of the cuticle display activity. Intense activity was also noted in the layer just under the shells of the eggs. The ovary and immature testes show high enzyme concentrations; however, in the testes, the concentration diminishes as the organs mature. In the scolex, the rostellum and the muscles of the suckers show higher enzyme activity than the surrounding tissues. The scolex, inner membrane, and tail of the cysticercoid show uniformly high concentrations of formazan.
Physiological studies on trematodes: the osmotic activity ofGastrothylax crumenifer
Authors: Goil Madan M.
Published: June 2009

The percentage change in weight, at 38·2 °C, in different concentrations of sodium chloride at different intervals, of a trematode,Gastrothylax crumenifer, from the reticulum of buffaloes has been recorded.

A state of approximate isotonicity is reached between 0·4 and 0·5% sodium chloride.

The osmotic pressure has also been expressed in terms of freezing-point depression.
A new species of Toxascaris from hyenas
Authors: Warren E. G.
Published: June 2009

Toxascaris versterae sp.nov. from hyenas in South Africa is described. T. versterae is compared with Toxascaris leonina, the only other member of the genus.

I thank Professor J. F. A. Sprent for his advice and criticism. This work was supported by grants from the Australian Research Grants Committee and from the U.S. Department of Health, Education and Welfare, No. AI-07023–03.
Immunity of rats and mice following injection with60Co irradiatedBabesia rodhainiinfected red cells
Authors: Phillips R. S.
Published: June 2009

Babesia rodhainiinfected mouse and rat red cells were non-infective after receiving 40 or 60 krad irradiation from a60Co source.

Rats inoculated with irradiated infected red cells were subsequently found to show strong resistance to homologous challenge.

Mice, which are more susceptible toB. rodhaini, showed less resistance to challenge, following immunization with irradiatedB. rodhainiinfected red cells.

Splenectomized rats were immunized with irradiated infected blood. There was a delay compared with the controls in the onset of acute fatal parasitaemias in these rats. A population of parasites was isolated by taking and mixing blood from each of the splenectomized rats during the patent parasitaemia following challenge. This population appeared to be an antigenic variant of the original immunizing population.

I thank Mrs J. Page for excellent technical assistance and Dr K. N. Brown for criticizing the manuscript.
The effect of an interferon inducer onEimeria maximain the chicken
Authors: Long P. L. , Milne B. S.
Published: June 2009

The intraperitoneal inoculation of chickens with 100–170 mg of Statolon, an artificial interferon inducer in mammals, induced the production of a virus interference factor in the serum. Chickens, 3 and 5 weeks old given 40–170 mg Statolon i.p. produced significantly fewer oocysts after infection withE. maximathan untreated chickens.

Only three serum samples (from a large number examined) taken from chickens 1, 4 or 6 days afterE. tenellainfection or 6 h and 6 days afterE. maximainfection showed slight but significant antiviral effects.
Theileria parva: Comparative infection rates of adult and nymphal Rhipicephalus appendiculatus
Authors: Purnell R. E. , Boarer C. D. H. , Peirce M. A.
Published: June 2009

Sections of salivary glands from adult R. appendiculatus ticks and sections of the whole bodies of nymphal R. appendiculatus ticks were studied to obtain data on the incidence and development of T. parva during feeding. Since, in their previous instars, all the ticks had dropped engorged from a parasitaemic calf on the same day, it was possible to compare the resultant infection rates in nymphs and adults.

In the adult ticks, the highest percentage infection (45%) and the greatest number of infected acini (45 from 20 ticks) were observed after 3 days feeding. Mature parasites were first seen after 4 days. In the nymphs, the highest percentage infection (35%) was observed after 3 days feeding. Equal numbers of infected acini (14 from 20 ticks) were observed in unfed nymphs and in those which had fed for 2 or 3 days. Mature parasites were first seen after 2 days, and all were mature after 3 days.

It was concluded that a batch of nymphs would contain more parasites per gramme than a corresponding batch of adult ticks. This fact, together with the observed uniformity of maturation of the parasites in nymphs, may make nymphs a more suitable choice than adults for the preparation of ground tick stabilates.

We are most grateful to Mr M. P. Cunningham, who inoculated the calf on which the ticks fed, and to Mr A. Musoke who observed the subsequent clinical reaction of the calf.

This work was carried out as part of the programme of the Immunological Research on Tick-borne Cattle Diseases and Tick Control Project which is supported by the United Nations Development Programme/Special Fund, with F.A.O. as the Executing Agency, in collaboration with the East African Community. The assistance of our colleagues on the Project is gratefully acknowledged. This paper is published by kind permission of Mr A. Rashid, the Director of the East African Veterinary Research Organization.
Observations on the movement of fluids in the vicinity of the mouthparts of naturally feeding Dermacentor andersoni Stiles
Authors: Gregson J. D.
Published: June 2009

Observations on the movement of fluids in the vicinity of the mouthparts of actively feeding female Dermacentor andersoni were made with the aid of trans-illuminated live-hamster pouch host-tissue. Following tick attachment and the invasion of ‘attaching cement’ into the outer skin layers, there appeared a progressive release of host blood as the tick settled into a feeding pattern. Short periods of sucking, each followed by an immediate ejaculation of saliva, became lengthened as feeding progressed, as did the resting intervals between sucking. Other movements brought about by the tick included a ‘toying’ of the tissue fluid, a rapid vibration of the same, and a distinct regurgitation of host-blood material. A sudden haemorrhage usually appeared at the feeding site about 2½ h after attachment of partially fed ticks.

Speculations are made concerning the part played by the release of tick saliva and tick water loss, its probable relationship to host paralysis, and its apparent role in tick nourishment.
The cat flea, Ctenocephalides felis felis (Bouché, 1835) as an intermediate host for cestodes
Authors: Marshall Adrian G.
Published: June 2009

The growth and development of Dipylidium caninum, Hymenolepis citelli, H. diminuta, H. microstoma, and H. nana were examined in Ctenocephalides felis, and the Hymenolepis species further examined in the reference host Tribolium confusum. This is the first recorded infection of C. felis with these four species of Hymenolepis and also of a flea with H. citelli.

Growth and development of the four species of Hymenolepis were comparable in C. felis and T. confusum. Observations relative to scolex formation indicated that perhaps only one basic sequence occurs in the genus Hymenolepis.

Growth and metamorphosis of the flea host had no important effects upon Hymenolepis development. However, presumably owing to greater crowding in C. felis than in T. confusum, an increased amount of retarded development was noted in cestodes from fleas. In contrast, the growth and metamorphosis of the flea host did affect the development of D. caninum. Little growth occurred in larval fleas but with the onset of pupation an increased growth rate was initiated, the cestode reaching almost its maximum size prior to the emergence of the adult flea. Cysticercoid differentiation and maturation mostly occurred within the adult.
Monocystid gregarines of Nigerian earthworms. I. Adelphocystis aeikineta gen.nov., sp.nov. from the coelom of Keffia variabilis Clausen, 1963
Authors: Cox F. E. G.
Published: June 2009

Adelphocystis aeikineta, a new species of monocystid gregarine, is found in the coelom of the earthworm Keffia variabilis in which the trophozoites occur in large numbers in permanently associated pairs. They are large, measuring 750–1500, μm in length, and exhibit continual peristaltic motion. The ectosarc of the trophozoite is markedly striated and there is no evidence of any anterior differentiation. The gametocytes are rounded and the presumed bipolar sporocysts measure 12–14·5 μm in length. Some associated pairs occur in groups enclosed in a membrane and there is evidence that gametocytes may form under these conditions. A. aeikineta is placed in the subfamily Zygocystinae and separated from Zygocystis on its elongate shape. The site of infection of this gregarine, and others recently described, suggests that the morphological basis on which the family Monocystidae is divided into subfamilies and genera is inadequate and a sounder classification should take into account these sites of infection.

The material on which this paper is based was collected while I was in receipt of a Wellcome Trust Travelling Grant, and I wish to thank the Trust for this support. It is also a pleasure to thank Mr R. W. Sims of the British Museum (Natural History) who identified the earthworms, Dr Keith Vickerman who helped me to collect them and Mr R. B. Freeman who advised me on the nomenclature.