bluuebunny/crossref_metadata_2025_split huggingface dataset:
The glucose metabolism of adult Ostertagia circumcincta, in vitro
Authors: Ward P. F. V. , Coadwell W. J. , Huskisson N. S. 
Published: June 2009

SUMMARYAdult Ostertagia circumcincta from freshly killed sheep were incubated at 39 °C in a medium containing inorganic salts, antibiotics and D-[U-14C] glucose. The worms appeared healthy even after incubation for as long as 72 h. All the radioactivity was recovered either within the worms or in the incubation vessel in the form of metabolic products or unmetabolized glucose. Incubations were carried out at low oxygen tension except for those in which CO2 was measured. These were either aerobic or anaerobic. In terms of both quantity and radioactivity the main metabolic products of glucose were CO2, propan-1-ol, acetate and propionate. Smaller amounts of ethanol, lactate and succinate were formed. The results are compared with those found for the similar nematode Haemonchus contortus.
Observations on arcade cells and pseudocoelomocytes in some oxyuroid nematodes parasitic in cockroaches
Authors: Peregrine Pauline C. 
Published: June 2009

Regions have been identified in certain oxyuroid nematodes which stain vitally with quinone-imine dyes. Thelastoma attenuatum shows colour in the arcade cells, the small pseudocoelomocytes and the giant pseudocoelomocytes; while Leidynema appendiculata and Hammerschmidtiella diesingi possess only giant pseudocoelomocytes. All these regions have been studied.The giant pseudocoelomocytes in all three species are apparently very active, but their precise function had not yet been assessed.The structure of the arcade cells and small pseudocoelomocytes of Thelastoma have been described. These regions may also be active but their function is again not understood.Further work to elucidate these problems is suggested.
The output of cercariae of Fasciola hepatica by Lymnaea truncatula and the distribution of metacercariae on grass
Authors: Hodasi J. K. M. 
Published: June 2009

It has been demonstrated that under normal laboratory conditions Lymnaea truncatula infected with Fasciola hepatica are not able to shed all their cercarial loads before their death. Cercariae are irregularly released over an extended period and considerable variations (4–1789) occur in their output.Laboratory studies have revealed that the green parts of grass (Dactylis glomerata) are preferred to the brown, dead parts by the cercariae of Fasciola hepatica for metacercariae formation. More cysts are formed on the lower surface of submerged leaves than on the upper surface.There is vertical zonation of metacercariae on grass in water. More cysts occur on the upper parts of submerged grass than on the lower parts.Vertical migration of cercariae after settling does not usually occur before cyst formation.The results are tabulated and discussed and correlated with conditio s in the field.This work was undertaken in the Department of Zoology, University of Bristol, Bristol, under the supervision of Dr H. D. Crofton, to whom I wish to express my gratitude.
Minocycline in the chemotherapy of murine toxoplasmosis
Authors: Tabbara K. F. , Sakuragi S. , O'connor G. R. 
Published: June 2009

SUMMARYThe effects of minocycline alone or in combination with sulphadiazine were evaluated against acute murine toxoplasmosis and compared with the efficacy of pyrimethamine and sulphadiazine. The data presented show that mice could be protected from acute toxoplasmosis by minocycline, in spite of using a virulent strain ofToxoplasma gondii, a large inoculum, and a delay in the administration of the drug. Acute toxoplasmic infection in mice could be eradicated by a minocycline–sulphadiazine combination, which was found to be as effective as pyrimethamine–sulphadiazine combination therapy.
The structure and possible function of the ventral papillae of Notocotylus triserialis Diesing, 1839
Authors: MacKinnon Barbara M. 
Published: June 2009

SUMMARYNotocotylus triserialis bears three rows of eversible papillae on its ventral surface. These papillae, which in living worms are firmly applied to the host mucosa, contain numerous pyriform cells. Histochemical tests indicate the presence, within the papillar cells, of protein, lipid, haemoglobin and esterase, and the absence of carbohydrate, acid mucopolysaccharide, RNA, haemosiderin and acid and alkaline phosphatase. Transmission electron microscopy shows the tegument of the papillae to be similar to the non-papillar ventral tegument. The pyriform cells contain many mitochondria with numerous cristae. A mechanism is proposed whereby the musculature of the worm effects the retraction and eversion of the ventral papillae.
Ultrastructural aspects of capsule formation in Trichinella spiralis infection in the rat
Authors: Teppema J. S. , Robinson Joke E. , Ruitenberg E. J. 
Published: June 2009

The encapsulation of Trichinella spiralis larvae in host striated muscle was studied.Capsule formation starts at 13 days post-infection. Between days 20–50 p.i. the largest increase in capsule formation was observed. The capsule is exclusively, or almost exclusively, formed from and by the infected muscle fibre, as might be concluded from the presence of the sarcolemmal basal lamina surrounding the capsule substance during the initial stages of capsule formation. A collagen nature of the capsule cannot be excluded.
The importance of parasite mortality in regulating the population size of the AcanthocephalanPomphorhynchus laevisin goldfish
Authors: Kennedy C. R. 
Published: June 2009

Experiments to study the mortality rate of the acanthocephalanPomphorhynchus laevisin goldfish are described. Infections with different population densities of parasite were given to fish on one occasion only and on several occasions with different time intervals between infection.The parasites established and grew in the experimental hosts at rates comparable to those in natural hosts on all occasions. The proportion establishing did not decrease with increasing population size and bore no relationship to the presence of an existing infection. The greatest loss of parasites occurred during the period of establishment. Thereafter, mortality was gradual, and the proportion of the population lost was not related to either the density of infection or to the intervals between infections. No evidence of reduced growth rate was found at the higher population densities.It is concluded that parasite mortality does not function as a feedback control and so is relatively unimportant in regulating the population size of fish acanthocephalans. Both field and laboratory evidence indicate that this is controlled by factors influencing recruitment. The equation of mortality and recruitment rates observed in many field populations must therefore be a matter of chance, and the implications of this with respect to the stability of fish-acanthocephalan systems is discussed.
The effect of the cestodeCaryophyllaeus laticepsupon production and respiration of its intermediate host
Authors: Kennedy C. R. 
Published: June 2009

A quantitative assessment of the effect of larvalCaryophyllaeus laticepsupon its intermediate host,Psammoryctes barbatus, was obtained by comparing the energy budgets of infected and uninfected tubificids from the same natural populationm throughout the course of a year. Measurements of the energy transformations during growth, reproduction and respiration of tubificids indicated some of the effects of the parasite.Infection had no influence upon the life-span of the host, but progressively decreased its growth and prevented reproduction. By contrast no significant differences were detected between the respiration rates of infected and uninfected animals. Decrease in the production of infected host tissue became apparent as soon as the parasite was detectable. Over the first 6 months loss in production due to the parasite was 50%, and over the whole life-span 59·9%. The production: respiration ratio of infected tubificids was also lower, but differences in assimilation were probably only small. The overall effects of the parasite upon its host population are slight, and the loss in tubificid nutriment available for fish food due to the parasite is less than 5% and of little economic importance. The way in which the parasite actually influences its host's physiology is discussed, and the effect ofC. laticepsupon its host's energy budget compared with that of a plerocercoid larva on its fish host.I should like to thank Dr M. Palmer for the loan of her Warburg flasks, Mr J. Harris for taking samples for me when I was unable to do so,'and Mr G. G. Vickers for many helpful comments and discussions on ecological energetics. I am also grateful to Mr G. Baileyfor combusting the samples for me.
Growth and respiration throughout the life-cycle ofNematospiroides dubiusBaylis (1926) (Nematoda: Heligmosomidae): the parasitic stages
Authors: Bryant Victoria 
Published: June 2009

The growth of male and female parasitic stages ofNematospiroides dubiusfrom male and female ASH/CS1 mice was measured in terms of dry weight. No sex-linked resistance of mice to infection withN. dubiuswas apparent, as growth was the same in both sexes of host. The growth rate did not alter when moulting occurred.All parasitic stages ofN. dubiusconsumed oxygenin vitroand oxygen was also shown to be necessary for motility and survival.The relationship between body size and metabolic rate was established for male and female parasiticN. dubiusand thebvalues indicated that aerobic metabolism is of functional importance to this species.The size/metabolism relationship for the whole life-cycle was established.
Nippostrongylus brasiliensis: further properties of antibody-damaged worms and induction of comparable damage by maintaining worms in vitro
Authors: Love R. J. , Ogilvie Bridget M. , McLaren Diane J. 
Published: June 2009

When adult Nippostrongylus brasiliensis were maintained in vitro they became damaged. Using the criteria of ultrastructural morphology, acetylcholinesterase isoenzyme pattern and the behaviour of the worms after transfer to a normal rat, this damage appeared to be similar to that produced by the in vivo action of antibodies.Antibodies were shown to be responsible for the anterior migration of adult worms which occurs during primary infections in mature rats and in the prolonged infections seen in lactating and immature rats.Antibody damaged worms and worms unaffected by antibodies were equally able to stimulate the immune response required for worm expulsion. Apparently antibody damage is not required for the initiation of the second immune component necessary for expulsion of this parasite.
Molluscs interfering with the capacity of Fasciola hepatica miracidia to infect Lymnaea truncatula
Authors: Christensen Niels Ørnbjerg , Nansen Peter , Frandsen Flemming 
Published: June 2009

Fasciola hepatica miracidia labelled with radioselenium were used to study aspects of their host-finding capacity by determining radioactivity subsequently taken up by exposed ‘target’ snails (Lymnaea truncatula). Possible interfering effects exercised by a number of non-host snails and bivalves were examined in linear test channels. The infection rate (radioactivity) among ‘target’ snails was markedly lowered when non-host Lymnaea species (L. pereger, L. palustris, L. stagnalis) were interposed as ‘decoys’. The prosobranch Bithynia tentaculata and the bivalve Sphaeriwm corneum exhibited a slight decoy effect whereas pulmonate species like Anisus vortex, Gyraulus albus, Planorbis planorbis, Physa fontinalis did not interfere with miracidial host-finding.Other experiments showed that miracidia are more strongly attracted towards L. truncatula than L. pereger. Miracidia are not able to penetrate intact egg clusters of L. truncatula.
Further studies on the use of chicken embryo infections for the study of drug resistance in Eimeria tenella
Authors: Chapman H. D. 
Published: June 2009

Infections in the chicken embryo have been used to study the development of drug resistance in an embryo adapted strain of E. tenella. Resistance was developed to decoquinate, clopidol and robenidine by serially passaging this strain, but evidence for the development of resistance to amprolium was inconclusive. Resistance to decoquinate developed more readily than to the other drugs. Attempts to increase resistance to clopidol, robenidine and amprolium by increasing the sporozoite inoculum and by the use of a mutagenic agent were unsuccesful. No cross-resistance was found between the 4 drugs.Drug resistant lines of the Houghton strain (H) of E. tenella, made resistant to the 4 anticoccidial drugs by passage in chickens, were found to be resistant when evaluated using chicken embryo infections. Lines made resistant to decoquinate were not controlled by any concentration of this drug, suggesting that resistance, once developed, was absolute and not dependent on drug concentration. Lines made resistant to robenidine, clopidol and amprolium, however, were controlled by higher drug concentrations suggesting that in this case resistance was dependent on drug concentration.
Immune responses to infections with coccidia in chickens: gut hypersensitivity
Authors: Rose M. Elaine , Long P. L. , Bradley J. W. A. 
Published: June 2009

Sporulated oocysts or oocyst hulls of Eimeria acervulina given via the crop, and oocyst juice or sporozoites inoculated directly into the in testinal lumen, were tested for their effects on the hypersensitivity of the intestines of immunized and susceptible birds. Only viable sporozoites consistently caused an increase in the permeability of the immunized intestine to macromolecules, shown by the leakage of intravenously injected dye. Repulsion of epithelium and disruption of the villi were seen more often in immunized than in susceptible chickens but there was no correlation with treatment or with dye leakage.The hypersensitive response of immune intestines challenged with a heterologous organism was approximately half as intense as the response to homologous challenge.The significance of these findings in relation to immunity to coccidiosis is discussed.
Studies on the biology ofProtopolystoma xenopodis(Monogenoidea): the oncomiracidium and life-cycle
Authors: Tinsley R. C. , Owen R. Wynne 
Published: June 2009

Protopolystoma xenopodis(Price, 1943) Bychowsky, 1957 is a parasite of the African clawed toads, species ofXenopus. Adult worms in the host's urinary bladder produce up to 15 eggs/24 h; these are voided with the urine and hatch after 20–24 days (at 26 °C). The swimming oncomiracidia enter the cloaca of the toad and travel via the urinary ducts to the kidneys. Larval development in the kidneys lasts 8–12 weeks (at 22 °C) and the juvenile parasites then migrate to the urinary bladder where maturity is reached after a further 3–4 weeks,i.e. 3–4 months after invasion. Egg production is continuous and parasite longevity has been found to exceed1½ years. Rarely, the adult worms may undertake a return migration from bladder to kidneys.The morphology of the oncomiracidium is described and compared with available accounts of other polystomatid genera. Consideration of data for the genusPolystomasuggests that the arrangement of the epidermal ciliary cells is relatively constant at the inter-specific level. Comparison ofProtopolystomawithPolystoma,DiplorchisandOculotremareveals that whilst the ciliary cell patterns are clearly related there are important differences in both cell number and disposition at the inter-generic level. Differences are also evident in the distribution of epidermal sensillae inProtopolystomaandPolystoma.Protopolystomais distinguished from all other polystomatids infecting anuran hosts by the presence of two pairs of haptoral hamuli.
In vitro oncospheral agglutination given by immune sera from mice infected, and rabbits injected, with eggs of Hymenolepis nana
Authors: Ito Akira 
Published: June 2009

Oncospheral agglutination given by sera immunized with Hymenolepisnana eggs is described as a new way of assessing H. nana infection. All sera of mice which possessed acquired protective immunity against reinfection by H. nana eggs had the potency to induce oncospheral agglutination in vitro. Only oncospheres, which had been hatched, agglutinated, no agglutination occurred in sera from uninfected mice. Oncospheral agglutination was carried out by mixing 0·1 ml of serial two-fold dilutions of serum and 0·1 ml of Hanks' balanced salt solution containing about 600 hatched oncospheres. Titre of agglutinins was indicated as a reciprocal of the final dilution capable of giving agglutination clusters made of three or more oncospheres. Agglutinins developed within 14 days after a primary infection with 500 shell-free eggs. There was no rapid increase of agglutinins within 4 days following a secondary infection. The titre increase coincided with the increase in dosages of eggs. Agglutinins were thought to be immunoglobulins, because the potency of the serum to agglutinate oncospheres was extinguished after absorption of globulins with rabbit anti-mouse globulin serum.Agglutinins were produced in rabbits by intravenous injections of shell-free eggs. The titres of the rabbit sera were much higher than those of mouse sera.
An experimental investigation of a direct life-cycle inReighardia sternae(Diesing, 1864), a pentastomid parasite of the herring gull (Larus argentatus)
Authors: Banaja A. A. , James J. L. , Riley J. 
Published: June 2009

A direct life-cycle inReighardia sternae, a cephalobaenid pentastomid of gulls was investigated: the work was prompted by a report of eggs and larvae recovered from the stomach and intestine of a naturally infected gull.Infective pentastomid eggs were obtained by surgically transplanting maturing femaleReighardia, taken from freshly shot wild gulls, into captive recipients. Faecal material from birds thus artificially infected was collected daily and examined for eggs. Eggs were force fed to 33 hand-reared (from eggs or nestlings) juvenile gulls which were selected at random and sacrificed at intervals thereafter and examined for pentastomids.One hour after infection, primary larvae appear in the body cavity where they moult immediately. They grow steadily and by 27–35 days are sexually differentiated, and by 66 days have copulated. Fertilized females take a further 116 days to produce eggs by which time they are 7·6 cm long.The complex migrations undertaken by developing larvae in the gull, and the problems of the mechanism of direct transmission, are discussed.
Heterologous immunity between piroplasms and malaria parasites: the simultaneous elimination of Plasmodium vinckei and Babesia microti from the blood of doubly infected mice
Authors: Cox F. E. G. 
Published: June 2009

SummaryMice which have recovered from infections with the avirulent piroplasm Babesia microti are also resistant to challenge with the virulent malaria parasite Plasmodium vinckei. In mice infected with P. vinckei before the peak of the B. microti infection the numbers of malaria parasites in the blood increase until that peak and are then eliminated at the same time as the piroplasms. In mice infected with P. vinckei at or after the peak there is no apparent multiplication and the malaria parasites begin to disappear from the blood immediately. The malaria parasites in doubly infected mice show signs of degeneration similar to those seen in mice pre-treated with Corynebacterium parvum and it is suggested that a common mechanism exists in homologous and heterologous immunity and in immunity following pre-treatment with C. parvum or BCG.
Trypanocidal activity of blood and tissue fluid from normal and infected rabbits treated with curative drugs
Authors: Goodwin L. G. , Tierney Ellen D. 
Published: June 2009

A new technique for determining the trypanocidal activity of body fluids has been devised, using very small quantities in the wells of plastic microtest plates.The activities of blood and tissue fluid of rabbits have been measured after the injection of melarsoprol, suramin, diminazene aceturate and isometamidium chloride. Activity againstTrypanosoma (Trypanozoon)bruceiPersisted in body fluids for a shorter time in treated normal rabbits than in treated rabbits infected with the tryponosome. The difference was caused by the participation of the immune response of the infected animals.The new technique was sensitive enough to detect these interactions of chemotherapy and immunology and should be of use in the study of new trypanocidal compounds.
The source and nature of some functional antigens of Trichuris muris
Authors: Jenkins Simon N. , Wakelin D. 
Published: June 2009

Vaccination with whole male worm extract (AMA), stichoseome extract (SA) and a short-term inculbation fluid (EXA) of adult Trichuris muris induced a high degree of protective immunity in mice as assessed by reduction in larval worm burden.Immunodiffusion of AMA against rabbit anti-AMA serum revealed five precipitin lines, one of which was common to both EXA and SA with which only single lines were obtained.Physico-chemical tests suggested that the antigen is a protein and that carbohydrate, lipid and DNA do not contribute to its antigenicity. Partial fractionation was obtained with ammonium sulphate. All preparations with immunogenic activity showed the common line of EXA on immunodiffusion.It is concluded that one of the protective immunogens is a protein which can be associated with the precipitin line and originates in the stichosome.
Babesia bigemina in Kenya: experimental transmission by Boophilus decoloratus and the production of tick-dervied stabilates
Authors: Morzaria S. P. , Young A. S. , Hudson E. B. 
Published: June 2009

A Babesia-free batch of laboratory reared Boophilus decoloratus ticks was infected with a Kenyan strain of Babesia bigemina by feeding them on a steer infected by inoculation of a blood stabilate. The engorged female ticks showed developing stages of B. bigemina in their haemolymph and subsequently their progeny transmitted the parasite to a susceptible splenectomized steer.Attempts were made to produce stabilates from pre-fed larvae and nymphs derived from infected batches of B. decoloratus. Only the stabilates derived from the nymphs pre-fed either on cattle or rabbits produced B. bigemina infection when inoculated intravenously into susceptible cattle.
Inhibited development in Ostertagia ostertagi infections – a diapause phenomenon in a nematode
Authors: Armour J. , Bruce R. G. 
Published: June 2009

Experiments are described which show that in a recently isolated field strain of the cattle nematode, Ostertagia ostertagi, the primary stimulus to the induction of inhibited development at the early fourth larval stage (EL4) in the host is chilling of the infective larvae (L3). Thus exposure of L3 to a temperature of 4 °C for 8 weeks prior to their oral administration to calves resulted in a mean of 66% of the established worm burden becoming inhibited at the EL4 stage. This provides an explanation for the seasonal occurrence in Britain of inhibited EL4 stages of O. ostertagi in cattle during the cold climate of late autumn and winter.If the L3 stages were exposed to chilling for a prolonged period (> 19 weeks), prior to infection of calves, then the prevalence of inhibited EL4 stages amongst the worms established declined. After 33 weeks chilling the worm population consisted almost entirely of adults and only 2% inhibited EL4 stages. This suggested that a selective mortality of inhibition prone L3 was taking place and explained why under natural grazing conditions inhibition prone L3 were not available on the pasture in spring.The duration of inhibition at the EL4 stage in calves infected with chilled L3 was consistently between 16 and 18 weeks and maturation of the majority of the inhibited larvae occurred spontaneously after such a period and irrespective of season. This period is equivalent to the duration of a normal winter in Britain when conditions unsuitable for the free living development of O. ostertagi larvae prevail.The induction of inhibition by the environmental stimulus of chilling, the fixed period for the duration of inhibition within the host and the spontaneous maturation of the inhibited larvae are characteristic of a true diapause.