bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies on carbohydrates in tissues and coenurus fluid of larvalTaenia multicepsfrom normal and alloxanized mice
Authors: Esch Gerald W. 
Published: June 2009

Results of the present study indicate that a wide range in coenurus fluid glucose concentration occurs among larvae ofTaenia multiceps. Further, a definite correlation exists between bladder size and glucose concentration in the coenurus fluid; larger bladders have greater glucose concentration per unit volume of coenurus fluid. Based on analyses of bladder fluid glucose following alloxan induced hyper-glycaemia, an abrogation of the established size-coenurus fluid glucose concentration occurred. A diabetic state did not alter glycogen concentration in the tissues or lactic acid levels in the fluids of the same coenuri. The functional significance of bladder fluid glucose in maintaining tissue glycogen at constant levels is briefly discussed.I wish to acknowledge Dr George Lauff, Director, W. K. Kellogg, Biological Station, for constructive criticism of the manuscript and for providing facilities and equipment during the summers of 1966 and 1967.
Anin vitrostudy of the effect of oxygen tension upon the motility ofNippostrongylus brasiliensis
Authors: Alphey Thomas J. W. 
Published: June 2009

An activity cell apparatus to facilitate quantitative measurements of motility of small nematodes in saline is described. The effects of salines with a pO2either greater than 120 mmHg or less than 12 mmHg upon the motility of adultN. brasiliensisfemales was studied. The worms were found to require an oxygen tension greater than 12 mmHg to be able to maintain their motility.I am grateful to Professors J. Brough and D. Bellamy for providing the facilities during the course of this study. I should also like to thank Dr R. A.Hammond for his supervision, help and criticism throughout the project, and Mr C. Welsby for his technical assistance in the construction of the activity cell.This work was carried out during the tenure of a Scientific Research Council Studentship.
The dynamics of the host-parasite relationship
Authors: Donald A. D. , Dineen J. K. , Adams D. B. 
Published: June 2009

An experiment has been conducted to examine the effects of discontinuous infection with H. contortus in sheep on the development of resistance to infection. When sheep were given four doses of 3000 larvae at fortnightly intervals and these sensitizing infections were removed on day 56, there was no evidence of resistance at that time nor of any residual effect of the sensitizing infections on the response to challenge at day 140. When, however, the sensitizing infections were permitted to persist until day 132, there was strong resistance to the establishment of a challenge infection whether or not the sensitizing worm burden was removed prior to challenge, and, in the case of superimposed challenge, resistance was coupled with rejection of most of the sensitizing population. When a single infection with 3000 larvae was followed 22 days later with a further single dose of 3000 larvae, there was no evidence of resistance whether or not the first infection was removed with anthelmintic. If the interval between two doses of 3000 larvae was extended to 76 days there was resistance to the establishment of the second dose if this was superimposed on the first, but not if the first infection was removed 8 days prior to the second dose.It is suggested that the manifestations of resistance appear in a sequence of (i) resistance only to a superimposed infection, followed by (ii) resistance to a challenge infection in the presence or absence of a previously existing worm burden, coupled in the former case with rejection of much of the existing population. This sequence could be related crudely to a product of larval dose and time. Although larval dose and time were to some extent confounded in the design of the experiment strong resistance was associated with prolonged uninterrupted infection.
Prototransversotrema steeri gen.nov., sp.nov. (Digenea: Transversotrematidae) from a South Australian fish
Authors: Angel L. Madeline 
Published: June 2009

Prototransversotrema steeri gen.nov., sp.nov. is found under the scales of the mullet, Aldrichetta forsteri, a euryhaline fish.It is distinguished from Transversotrema Witenberg, the only other genus of the family Transversotrematidae by the possession of an oral sucker as well as a pharynx. This necessitates alteration of the family diagnosis.Knowledge of the life-histories of Transversotrema spp. is summarized. The so-called ‘metacercariae’ found under the scales of freshwater and euryhaline fish are regarded as adults. When they have no eggs or only one egg they have probably developed in a fish which is not the normal host.P. steeri escapes from under the scales of the fish shortly after the latter is caught. It is suggested that this habit may account for the small number of species known in the family.
Enzyme electrophoresis and speciation of Schistosoma intermediate hosts
Authors: Coles G. C. 
Published: June 2009

1. Enzyme electrophoretic patterns from populations of snails, intermediate hosts of Schistosoma, have been examined.2. Esterase patterns (α-naphthyl butyrate as substrate) have been used to differentiate snail populations of B. africanus and Biomph. pfeifferi.3. Malate, β-hydroxybutyrate and α-glycerophosphate dehydrogenases may be of use in some cases to distinguish between species, e.g. B. africanus v. B. ugandae and Biomph. sudanica v. Biomph. pfeifferi.
The regulation of populations ofOstertagia ostertagiin calves
Authors: Michel J. F. 
Published: June 2009

The course of the worm burdens of calves infected daily with larvae ofOstertagia ostertagiat five different rates was studied by making post-mortem worm counts on groups of calves killed after experiencing infection for different periods of time.The relationship between worm numbers and infection rates together with evidence that a turnover of worms occurred, led to the conclusion that burdens of adult worms were regulated primarily by a loss of worms at a rate proportional to the number present.Further, estimates based on the number of developing fourth-stage larvae indicated that the proportion of the larvae administered which became established decreased gradually as the experiment progressed.At very low infection rates, the rate of turnover of the worms was slower than at high infection rates but in all groups it remained constant through the 6 months duration of the experiment.The development of a small proportion of the larvae administered was arrested at the early fourth stage. At the highest infection rate used, the proportion of worms that became inhibited was somewhat greater.
Studies on the distribution and site location ofNippostrongylus brasiliensiswithin the small intestine of laboratory rats
Authors: Alphey Thomas J. W. 
Published: June 2009

The distribution ofN. brasiliensiswithin the small intestine of rats, following a primary infection, is described.The fourth stage larvae were found to inhabit the sections later parasitized by the adult population.Both the larval and adult worms were found to be confined to the anterior half of the small intestine. This aggregation is believed to be under the influence of stimuli (factor(s) 1), present in the lumen of the host gut.The adult worms also clumped within the already confined worm population. This behaviour is thought to be due to intrinsic behaviour patterns of the worm, sexual attraction and thigmokinesis.Larval and adult worms were surgically transferred to points, at varying distance from the ‘normally’ inhabited region, in the small intestine of fresh recipient rats. The resulting migratory behaviour of the worms was studied.The worm populations resulting from both the larval and the adult transfers showed the ability to recognize that they were in the wrong position of the small intestine and to be able to orientate, migrate and locate the ‘normal’ site.
Scanning and transmission electron microscopy ofEimeria maximamicrogametogenesis
Authors: Ball S. J. , Pittilo R. M. , Joyner L. P. , Norton C. C. 
Published: June 2009

SUMMARYThe structure and development of microgametocytes ofEimeria maximafrom chicks killed during the 6th day of infection were examined using transmission and scanning electron microscopy. Initially, nucleoli disappear and the surface of the microgametocyte invaginates. This is followed by a condensation of the chromatin which then lies at the periphery of the nuclei. Concurrent with this, the flagella are formed and they project into the parasitophorous vacuole and internal invaginations. Eventually, the nuclei become more dense and are seen to protrude from the periphery of the gametocyte. The surface view of mature microgametocytes consists of a large number of closely packed flagella.
Trypanosoma bouffardiof West African Ploceidae (Aves)
Authors: Molyneux D. H. 
Published: June 2009

Trypanosoma bouffardiLeger & Blanchard, 1911, is described from naturally infectedLagonosticta s. senegala, Estrilda b. bengalus, Vidua chalybeata, Estrilda t. troglodytesandAmadina f. fasciata, all of which are new host records for Nigeria;Vidua chalybeatais a new host record for trypanosomes.There was no significant morphological difference between populations of this trypanosome in the various natural and experimental vertebrate hosts.T. bouffardiwas transmissible to nine species of Ploceidae belonging to the three subfamilies Estrilinae, Ploceinae and Viduinae; but not toPycnonotus barbatus, chickens or pigeons.The parasitaemia produced by infections ofT. bouffardireached 4·1 × 105parasites/mm3of blood.Reproduction of the trypanosomes was synchronous and discontinuous and occurred in the blood by unequal binary fission of trypomastigotes. Occasionally longitudinal equal binary fission of trypomastigotes also took place. There was no concentration of dividing forms in the tissues.T. bouffardidid not grow on NNN medium although it has been grown for a short time on the medium described by Yesufu (1970).
Larvae of Dichetophora biroi (Kertesz, 1901) (Diptera: Sciomyzidae) feeding on Lymnaea tomentosa (Pfeiffer, 1855) snails infected with Fasciola hepatica L.
Authors: Fontana P. G. 
Published: June 2009

An experiment was performed to test whether the larvae of the sciomyzid fly Dichetophora biroi are able to ‘recognize’ and reject Lymnaea tomentosa snails infected with Fasciola hepatica.The analysis of the results indicates that the larvae do not show any obvious preference when given the simultaneous choice of non-infected and infected snails, and also that, under laboratory conditions, the latter are not more vulnerable than the former to the larval predation.I wish to express my sincere gratitude to Dr R. P. Herd for his help and encouragement during this work. I am also grateful to Professor C. O. Berg, Cornell University (U.S.A.); Dr J. J. Lynch, C.S.I.R.O. Pastoral Research Laboratory, Armidale (N.S.W.) and Dr M. D. Rickard, University of Melbourne, for valuable advice and fruitful discussions. Dr J. A. Thomson, University of Melbourne, critically read the manuscript.
A comparison of the effects of infection with Eimeria maxima and dietary restriction on weight gain, plasma metabolites and liver glycogen in the immature fowl, Gallus domesticus
Authors: Chapman H. D. , Fernandes D. L. , Davison T. F. 
Published: June 2009

SUMMARYThe effects of Eimeria maxima or restricted pair-feeding on weight gain, plasma concentrations of protein, glucose, free fatty acids (FFA) and uric acid and liver glycogen were compared in immature fowl. Food intake/kg body weight and weight gain decreased during the acute phase of infection (days 5–7) while weight loss was prolonged for an extra day compared with pair-fed birds. During recovery, food intake/kg body weight of infected birds was greater than that of non-infected controls but there was no evidence for an increase in growth rate compared with controls when body weight was considered. Growth rate of pair-fed birds was greater than that of infected birds during recovery, indicating their better use of ingested food. Liver glycogen and plasma protein concentration were decreased during the acute phase of infection but the concentrations of plasma glucose, free fatty acid (FFA) and uric acid were not affected. In pair-fed birds liver glycogen was depleted, concentrations of plasma glucose and uric acid decreased and FFA increased, and these changes persisted for the remainder of the experiment. The findings are similar to those in birds whose food has been withheld and were probably due to the pattern of food intake imposed by the experimental protocol. It is concluded that the metabolic differences between infected and pair-fed birds are of doubtful significance.
The cell surface ofPlasmodium gallinaceum sporozoites: microelectrophoretic and lectin-binding characteristics
Authors: Turner D. P. , Gregson N. A. 
Published: June 2009

SUMMARYThe cell surface properties ofPlasmodium gallinaceumsporozoites have been investigated by means of microelectrophoretic and lectin-binding studies. Their electrophoretic mobility has been measured as a function of pH, the results suggesting qualitative and quantitative differences in the surface ionogenic groups between sporozoites from mature oocysts and those from salivary glands. Reaction of sporozoites with citraconic anhydride produced a small but significant increase in mobility, whereas 5,5-dithio-bis-(2-nitrobenzoic) acid had no effect on mobility; thus there appear to be amino groups but not –SH groups at the surface of sporozoites. Treatment of sporozoites with trypsin considerably reduced their mobility and suggests that a significant proportion of the cell surface charge is associated with protein. Incubation with neuraminidase, however, had no effect on sporozoite mobility and indicates that sialic acid residues, responsible for much of the negative charge associated with mammalian cells, are probably not present on the cell surface of sporozoites. Evidence for the presence of carbohydrates on the cell surface membrane of sporozoites was sought using fluorescein isothiocyanate–Concanavalin A. Results demonstrated that ligands similar to α-D-glucose and α-D-mannose are not present in an exposed or reactive form on the cell surface membrane ofP. gallinaceumsporozoites.
Studies on the hatchability of Schistosoma mansoni eggs from a naturally infected human community on St Lucia, West Indies
Authors: Upatham E. S. , Sturrock R. F. , Cook J. A. 
Published: June 2009

A relatively simple, standardized hatching test was devised, tested and used to estimate the Schistosoma mansoni hatching rate for 88 St Lucian subjects selected by age, sex and intensity of infection.The hatching rate was dependent on the intensity of infection and rose proportionately with it. The rate also decreased with increasing age of the subject. Sex alone had no direct effect but there was a suggestion of an interaction between sex and age.These results suggest that several hatching tests are necessary, before and after treatment in schistosomicidal drug trials, to permit valid conclusions to be drawn. The hatching data are used in conjunction with survey results to calculate the contamination potential of different age groups in a population. School children (5–14 years old) are about twice as important as young adults (15–29 years old) who, nevertheless, contribute over a quarter of the total contamination potential. However, whereas school children are fairly accessible for mass chemotherapy control programmes, young adults often are not and, furthermore, involve problems associated with the treatment of women of child-bearing age.
Dynamic determinants of the route of larval Strongyloides ratti in lactating rats and the control of experimental error in quantitative studies of milk transmission of skin-penetrating roundworms
Authors: Wilson P. A. G. , Gentle Maureen , Scott D. S. 
Published: June 2009

Subcutaneous injection of nursing mothers from day 16 to day 20 post partum with infective larvae of Strongyloides ratti or Nippostrongylus brasiliensis does not result in the development of worms in the litters if 1 h is allowed between injection and resumed nursing, and suckling is terminated 24 h later. Thus the low numbers of N. brasiliensis (1% of the dose) which develop in litters after 24 h, 4 day or 5 days suckling when mothers are injected and returned to their young immediately, represent skin invasion and not milk-borne infection.Taking precautions consistent with the foregoing, S. ratti equivalent to 28%, 45%, 45% and 48% of the dose were shown to be transmitted in the milk to suckling rats of 4 mothers injected with 4000 L 3 on day 18 post partum and 72 h before weaning. One mother of the same batch failed to transmit worms (1% of the dose in the litter) and the take in all 5 mothers was insignificant (max. = 3% of the dose versus an average of 21% in controls).Large numbers of S. ratti were subsequently found in the intestines of mothers whose litters were weaned immediately after (21%) or 6 h after (16%) injection, whereas very few (less than 1%) developed in mothers deprived of their offspring 24 h after injection. Dynamic, rather than static, determinants of larval routes inside the host present the only logical basis for an explanation of these facts.
The use of vitamin K deficient diets in the screening and evaluation of anticoccidial drugs
Authors: Ryley John F. , Hardman Linda 
Published: June 2009

SummaryVitamin K (as menaphthone sodium bisulphite) added to a deficient diet reduced mortality due to Eimeria tenella or E. necatrix, had a slight effect on haematocrit, but had no obvious effect on weight gain or faecal blood; 0·1 ppm gave a maximal response. The effect of vitamin K on mortality was not absolute; the magnitude of the effect depended on the size of the challenge dose of oocysts. Likewise, the response of an infection to anticoccidial drugs, particularly monensin, depended on the severity of challenge. The effect of adding vitamin K in the presence of drug was to effectively reduce the coccidial challenge; no other interaction of vitamin K and drug has been found. No effects with vitamin K deficiency or supplementation were seen in cases of infections with E. acervulina, E. brunetti or E. maxima. The use of a deficient diet for experimental work is therefore quite justified – particularly as it results in a 4-fold saving of oocysts for inoculation purposes in the case of the haemorrhagic species.
Trans-tegumental absorption of L-alanine and L-leucine by a monogenean, Diclidophora merlangi
Authors: Halton D. W. 
Published: June 2009

SummaryAn in vitro investigation has been made of the relative roles of the gut and tegument in the absorption of the neutral amino acids L-alanine and L-leucine by a marine fish-gill parasite, Diclidophora merlangi. The use of ligatures to preclude oral ingestion of trace-labelled medium has proved inadequate, invariably damaging the tegument, as revealed by stereoscan electron microscopy, and resulting in artifactual levels of absorption. Three alternative procedures have given consistently reliable data on the route of entry of low molecular weight substrates. (1) Ultrastructural examination of worms previously incubated in electron-dense cationic tracers has shown that, in vitro, there is no oral intake of sea water. (2) The suspending of worms in trace-labelled medium with the mouth out of the medium and comparing amino acid uptake with that of worms totally immersed in medium has revealed no statistically significant difference in the absorption levels. (3) Application of section (freeze-dried) auto-radiography to detect diffusible isotope has demonstrated directly transtegumental absorption of a neutral amino acid. It is concluded from these experiments that Diclidophora has a tegumental transport system for absorbing certain neutral amino acids, and whilst, clearly, the worm is sanguinivorous and digests blood in a well-developed gut, it may also be capable of supplementing this diet with low molecular weight organic nutrient absorbed directly from sea water via the tegument.
Haemoflagellates: commercially available liquid media for rapid cultivation
Authors: Hendricks L. D. , Wood D. E. , Hajduk M. E. 
Published: June 2009

SummaryThe successful cultivation of a variety of haemoflagellates in three different liquid media is reported. These media include medium 199, Grace's insect tissue-culture medium and Schneider's drosophila medium, each in combination with 30% (v/v) foetal calf serum. These media were used to cultivate Old and New World species of visceral and cutaneous human Leishmania, as well as Leishmania species isolated from sandflies, rodents, and reptiles. Four strains of Trypanosoma cruzi, an isolate of T. rangeli and an isolate of T. lewisi have also been cultivated in these media. One or more of these media have been used to cultivate 121 strains of haemoflagellates, including at least 14 different species (11 Leishmania and 3 Trypanosoma) and many geographic isolates or strains. The Leishmania include L. braziliensis, L. peruviana, L. mexicana, L. tropica, L. donovani, L. chagasi, L. enriettii, L. hertigi, L. hoogstraali, L. adleri, and L. agamae. Using the Schneider's based medium, we have obtained primary isolates of both cutaneous and visceral Leishmania of man and of experimentally infected laboratory rodents and canines. Freeze-dried preparations of the Schneider's based medium that were reconstituted with distilled water after 24 months of storage at ambient temperature have proven to be suitable cultivation media. This feature makes the media valuable field tools.The various species of human Leishmania cultivated in these media have in our experience demonstrated no differences in growth rate, viability after liquid nitrogen preservation, or infectivity for laboratory animals and tissue-culture cells compared with promastigotes derived from blood-agar cultivation.
Variations in the ultrastructure of the daughter sporocyst ofMicrophallus pygmaeus(Levinsen, 1881) (Digenea: Microphallidae) in chemically defined media
Authors: Popiel Irene , James B. L. 
Published: June 2009

SummaryChanges in the ultrastructure of the daughter sporocyst and contained metacercariae ofMicrophallus pygmaeusduring culture in artificial seawater and modified Medium 199 were examined and compared with variations in oxygen consumption. The very early commencement and rapid progression of autolysis in the sporocyst body wall as compared with little or no change in most metacercariae in both media, together with the elevated oxygen consumption in the nutrient medium, suggests that most of the oxygen is consumed by the contained metacercariae. The almost simultaneous onset of body wall degeneration in both media suggests that the nutrient medium is not suitable for the maintenance of healthy daughter sporocysts.
Phosphoglucomutase polymorphism in the tick Ixodes ricinus
Authors: Healy J. A. 
Published: June 2009

SUMMARYTen variants of phosphoglucomutase were detected by starch-gel electrophoresis in extracts of the tick Ixodes ricinus. Agreement of phenotype frequencies with those predicted by the Hardy–Weinberg model indicated that the enzyme is coded by a single gene locus (Pgm) at which 10 alleles are segregating. Allelic proportions in 5 Irish tick samples indicated that both spatial and temporal genetic differentiation exist. It is suggested that this polymorphism may be of use as a marker for studying the relationships of I. ricinus populations in Europe, as well as in taxonomic studies. A hypothesis is advanced which offers a possible adaptive explanation of the very high Pgm heterozygosity in tick populations. It is suggested that if kinetic differences exist between the various enzyme variants, the polymorphism may act to maintain an array of individuals in each population with varying developmental rates and longevities. Such a genetic strategy could be one factor which determines that the host-infesting seasons are spread over several months, thus ensuring maximum feeding and reproductive rates in each population.