bluuebunny/crossref_metadata_2025_split huggingface dataset:
The morphology and life cycle of Plistophora scatopsi sp.nov., a microsporidian parasitic in the mid-gut of Scatopse notata Mg. (Diptera, Nematocera)
Authors: Hiller Sylvia R. 
Published: June 2009

1. The morphology and life cycle of a new microsporidian, parasitic in the mid-gut epithelium and caeca of the larvae of Scatopse notata, and also present in the pupae and flies, is described.2. The name Plistophora scatopsi sp.nov. is proposed.
Louse populations of some rodents of the Great Salt Lake desert
Authors: Ignoffo Carlo M. 
Published: June 2009

During the period extending from February 1955 to January 1956, 192 specimens of deer mice, Peromyscus maniculatus sonoriensis (LeConte), 174 specimens of white tail antelope ground squirrels, Citellus leucurus leucurus (Merriam) and 154 specimens of Ord kangaroo rats, Dipodomys ordii pallidus (Durrant & Setzer), were examined to determine louse-host associations, rate of infestation, frequency of distribution and seasonal fluctuation of louse populations.Five species of lice were recovered from three species of rodents. The dominant species on the deer mouse was Hoplopleura hesperomydis (Osborn). The dominant species on the white tail antelope ground squirrel was Neohaematopinus citellinus Ferris. The only louse species recovered from the Ord kangaroo rat was Fahrenholzia pinnata K. & F.Infestation on rodents was recorded on the basis of percentage of hosts infested, number of lice per host and number of lice per infested host. The highest number of lice per host was 27·7 Neohaematopinus citellinus per infested white tail antelope ground squirrel. The lowest value was 2·5 Polyplax auricularis per infested deer mouse.Approximately 80 % of the rodent sample had less than 25 lice per host. This grouping accounted for about one-half of the total number of recovered lice.Seasonal fluctuations of louse populations on deer mice, white tail antelope ground squirrels and Ord kangaroo rats were studied over one complete year. There appeared to be some coincidence between rodent activity, temperature and louse populations.
The complement-fixation test in Bilharziasis II. Preparation and preservation of antigens from Schistosoma mansoni worms extracted in Coca's solution
Authors: Eliakim M. , Davies A. Michael 
Published: June 2009

1. Adult S. mansoni worms were extracted in Coca's solution at various temperatures by different methods. The most potent antigen was obtained by extracting a worm suspension, diluted 1:500, at 37° C. for 1 hr., with vigorous shaking at 10 min. intervals, followed by 23 hr. at 28° C. Second extraction of worm samples gave highly active material and third extractions also contained antigen.2. Complement-fixation tests, performed with the sera of twenty-five patients with chronic bilharziasis and twenty-five healthy subjects showed that the most specific results were obtained with either the first two extracts of worms, suspended in 100 parts of Coca's solution, and extracted for 1 hr. at 37° C. and 23 hr. at 28° C., or with the first extract of worms, suspended in 500 parts and extracted in the same manner.3. Samples of an extract in Coca's solution were preserved for 170 days by different methods, and their activity was tested at approximately monthly intervals. The antigen, with or without the addition of 0·1% cysteine, retained its titre for 1 month, when kept in the refrigerator. Freezing, or lyophilization of the extract caused a rapid drop in titre.4. Titration of extracts of lyophilized worms, from freshly opened ampoules, showed that a constant titre was retained for 3½ months followed by a slight drop after 5–6 months. The worm powder retained its antigenic potency when kept, thoroughly desiccated, in the refrigerator for 4 months, but lost it in 40 days when partial rehydration occurred.
Electron microscopic observations of toxoplasma ‘Nicolle et Manceaux’ grown in tissue cultures (first note)
Authors: Meyer H. , de Andrade Mendonça I. 
Published: June 2009

Toxoplasma ‘Nicolle et Manceaux’ has been examined in the electron microscope in in toto preparations from tissue cultures.The extracellular as well as the intracellular forms of the parasite are too thick for an adequate penetration of the electron beam, and the inner structure of Toxoplasma is not revealed in these preparations.The whole parasite is covered by a very delicate, transparent mantle which may extend to form large membranes. They show no structure in the electron microscope. No sheath has been observed which protects the shape of the parasite. Most of the free forms have an irregular surface and tend to become flat and large.Several pictures illustrate the way in which Toxoplasma penetrates the tissue cells. In the beginning of parasitism the limits between cytoplasm and parasite are difficult to recognize. The region of the cytoplasm around the parasite is gradually dissolved and a vacuole is formed.
Immunological response of the hosts to Toxocara canis (Werner, 1782) infection I. Effect of superinfection on naturally infected puppies
Authors: Fernando S. T. 
Published: June 2009

Superinfection of naturally infected puppies with large numbers of Toxocara canis eggs induced a self-cure reaction. There was a sharp fall in Toxocara egg output following superinfection in most of the puppies. In most, but not all the puppies, the existing worm burden was eliminated. Eliminated worms were full of fertile eggs, but, in the puppies in which egg production fell sharply without expulsion of the worm burden, egg production by the naturally acquired worms was suppressed only transiently.Antibody production, measured by the complement-fixation test, was directly related to resistance to superinfection but not to self-cure.Acquired resistance reduced the pathogenic effects of superinfection, and prevented development of the parasite beyond the second stage.It is a pleasure to thank Professor P. Seneviratna, University of Ceylon, for his constructive criticisms of the manuscript and the facilities provided.The writer thanks Mr W. G. Senaratne for technical assistance and typing of the manuscript.This work was carried out with a special research grant from the University of Ceylon.
A histological description of the uterine bell of Polymorphus minutus (Acanthocephala)
Authors: Whitfield P. J. 
Published: June 2009

The cellular and syncytial components of the mature uterine bell of the palaeacanthocephalan, Polymorphus minutus are described, and compared with previous accounts of the histology of uterine bells. Each uterine bell always contains 17 separately distinguishable nuclei. This situation provides a good illustration of the phenomenon of organ eutely, common in Acanthocephala. The luminal spaces of the bell are described and their relevance to the translocation of eggs discussed.I should like to thank Dr D. W. T. Crompton for his help and encouragement during the course of this work and Dr P. Tate for the provision of facilities. The work was carried out during the tenure of an S.R.C. Research Studentship.
A study of the Eugregarines of the grass-grub [larva of Costelytra zealandica (White), Melolonthinae], with a description of three new species
Authors: Allison F. R. 
Published: June 2009

1. Three new species of eugregarine are described from the mid-gut of the larva of Costelytra zealandica (White).2. Euspora zealandica occurs in the anterior region of the mid-gut near the gut caeca. Slictospora costelytrae occurs just posteriorly to E. zealandica. Euspora sp. occurs posteriorly to the malpighian tubules, but was found only rarely.3. A description of the species and the life-cycle of two species are given.4. The life-cycle of S. costelytrae takes about 8 weeks and that of E. zealandica 6 weeks.5. Gametocysts will develop only at a humidity of 95–100 %.6. The bi-associative species, E. zealandica, is more abundant in the 1st and 2nd instars than the large species, S. costelytrae. Both species are equally abundant in the 3rd instars, but the peak for incidence was in May for E. zealandica and June for S. costelytrae. This is related to the longer period of time taken for the life-history of S. costelytrae.7. The incidence of gregarines builds up in each instar to over 90% then falls off, the time of fall off corresponding with the production of gametocysts which pass out with the faeces of the grub.8. The gregarines mostly complete their cycle before the instars moult. This is borne out by the observation that cysts were not found in the smallest size group of each instar. There were many cases in the larger size group of all three instars where cysts only occurred.9. Gametocysts are produced mainly in the autumn.10. Gregarines were not found in grubs approaching metamorphosis (prepupae) nor in pupae nor adults.11. It seems unlikely from the results that the gregarines have an adverse effect on the grubs as, in general, it was found that the larger grubs had the greater number of gregarines present, but further work on this is needed.12. The life-history of the gregarines is closely correlated with the life-history of the beetle.13. The presence of the gregarines only in the larval stages is related to the different habitat and behaviour of larva and adult.I am grateful to the University Grants Committee for financial support.
Damage to adult Schistosoma mansoni after transfer to a hyperimmune host
Authors: Hockley D. J. , Smithers S. R. 
Published: June 2009

Adult S. mansoni from a recently infected rhesus monkey (Macaca mulatta) were transferred into the hepatic portal systems of a normal rhesus and of a rhesus which had acquired complete resistance to the parasite. The worms were recovered after 2 days and examined by light and electron microscopy.The worms recovered from the normal monkey were undamaged. Most of the worms recovered from the hyperimmune monkey were alive but had localized aggregations of host cells on their surfaces. Small areas of the tegument of these worms showed structural and degenerative changes, namely an increase in density and vacuolation of the tegument; the formation of small, round, membrane-bounded cytoplasmic bodies within vacuoles in the tegument; the breakdown of the outer membrane of the tegument and release of the cytoplasmic contents; and finally the complete disappearance of the tegument exposing the underlying muscle fibres. Host monocytes and polymorphonuclear leucocytes were closely applied to severely damaged parts of the tegument; the host cells appeared to be phagocytic. The other tissues of the worms were normal. Apparently the above damage is a result of the host's immune reaction which is directed against the tegument of the worms. Worms grown in mice and subsequently transferred to monkeys immunized against mouse antigens are similarly damaged, but in this case the damage occurs more rapidly.
Histochemistry of the lung mite pigment in infections ofPneumonyssussp. in non-human Primates
Authors: Brack M. 
Published: June 2009

Histochemical analyses of the pigment accompanying lung mite infections in Old World monkeys indicate that, contrary to other endogeneous pigments, this pigment is not homogenous, but consists of at least three components. One fraction is formed by fine granular or amorphous cleavage products of mucin substances, the second portion appears to be large granules of haemosiderin and/or lipofuscin, and the third component consists of needle-like crystals of unknown chemical nature. The source and nature of the pigment are discussed.I am grateful for the technical assistance of Mrs J. A. Silva and the support by Drs R. T. Damian, S. S. Kalter, R. E. Kuntz and B. J. Myers; Southwest Foundation for Research and Education, San Antonio, Texas.This study was funded in part by U.S.P.H.S. Grants RR-00361, RR-00278 and RR-00451 and WHO Grant Z2/181/27.
Haemonchus contortus-the effect on lambs of prolonged exposure to daily and weekly doses of infective larvae
Authors: Pradhan S. L. , Johnstone I. L. 
Published: June 2009

Thirty-five lambs (14 weeks old), the progeny of Border Leicester rams mated with Border Leicester × Merino ewes, were divided at random into two groups. Seventeen lambs in Group A received 3500 Haemonchus contortus larvae weekly and 18 lambs in Group B received 500 larvae each day: the dosage was decreased to 1400 larvae weekly and 200 larvae per day after 8 weeks.Pathogenicity was found to be higher when the lambs were infected with a small number of larvae daily (daily group) than when the same number of larvae were given in one dose at weekly intervals (weekly group). The period of survival was consistently shorter in the former group.No significant difference in faecal egg counts was observed between the two groups.Reduction in food intake per head per day and in live weight were more pronounced in the ‘daily group’ than in group dosed weekly. The discrepancy in food consumption and live weight between these two treatments was more apparent at the end of the experiment.Some resistance was observed in both groups but the level of resistance was not high.Accumulation of inhibited larvae was apparent after 104 days in the ‘weekly group’ and after 78 days in the ‘daily group’. An infection arising from a large number of larvae given at weekly intervals induced a mild form of resistance leading to an accumulation of inhibited larvae at the end of the experiment. This was less apparent in lambs infected with the same number of larvae given each day.Interference with ovulation in adult females was recorded in both treatments. Sex discrimination against the female population both in the extent of elimination of adults and in the retardation of development of fourth-stage larvae was recorded and the intensity of discrimination was more pronounced with the weekly regime of larger doses than with the same number of larvae but given in daily doses. The worms were eliminated sporadically and not continuously. A challenge infection of 10000 larvae given to two lambs in the ‘weekly’ regime treatment on the 107th day initiated a partial selfcure reaction demonstrated by an immediate fall in faecal eggs per gram (i.e. Epg) but the egg count returned to the original value in 28 days.
An egg-adapted (attenuated) line of Eimeria necatrix: further studies on its reproduction, pathogenicity and immunogenicity
Authors: Shirley M. W. , Bellatti M. A. , Millard B. J. 
Published: June 2009

SUMMARYAn egg-adapted line of Eimeria necatrix has now been passaged 40 times in the chorio-allantoic membranes of embryonated eggs. Between the 21st and 40th passage in eggs the parasite was subjected to a selection for precocious development, and its pre-patent period in this host is now 123–125 h. The parasite continued to adapt to the chorio-allantoie this tissue caused the growth of the host embryo to be markedly stunted. In chickens, both the reproduction and the pathogenicity of the egg-adapted line decreased with increasing numbers of passages in eggs. A comparison of teh immunogenicity of te egg-adapted line and its parent strain in chickens kept on litter, showed that substantially more oocysts of the egg-adapted line had to be given to induce complete protection.
Intermediary carbohydrate metabolism in protoscoleces ofEchinococcus granulosus(horse and sheep strains) andE. multilocularis
Authors: McManus D. P. , Smyth J. D. 
Published: June 2009

SUMMARYWith few exceptions, the specific activities of the glycolytic enzymes and the steady-state content of glycolytic and associated intermediates in protoscoleces of the horse (E.g.H) and sheep (E.g.S) strains ofEchinococcus granulosusand the closely relatedE. multilocularis(E.m.) are very similar. Phosphorylase, hexokinase, phosphofructokinase and pyruvate kinase catalyse non-equilibrium reactions and the patterns of activity for pyruvate kinase, phosphoenolpyruvate carboxykinase and malic enzyme are similar in the three organisms. The levels of tricarboxylic acid cycle intermediates inE.g.H., E.g.S. andE.m. are of the same order as those reported in tissues with an active cycle. Each has a complete sequence of cycle enzymes but there are substantial differences between the three parasites with regard to the activity of individual enzymes, The activities of NAD and NADP-linked isocitrate dehydrogenases are significantly lower inE.g.H. than inE.g.S. and particularly inE.m. which suggests that the tricarboxylic acid cycle may play a more important role in carbohydrate metabolism and energy production in the latter parasites. Nevertheless, the three organisms utilize fermentative pathways for alternative energy production, fix carbon dioxide via phosphoenolpyruvate carboxykinase and have a partial reversed tricarboxylic acid cycle. It is speculated thatin vivomore carbon will be channelled towards oxaloacetate than pyruvate at the phosphoenolpyruvate branch point. The steady state content of ATP and the ATP/AMP ratios are low in the three organisms, suggesting a low rate of ATP utilization in each.
Studies on the relationship between Eimeria acervulina and Eimeria mivati
Authors: Long P. L. 
Published: June 2009

Two strains each of Eimeria acervulina and Eimeria mivati were examined for their ability to develop in the chorioallantoic membrane (CAM) of chicken embryos and the caeca of chickens. It was found that between 100 and 1000 times more sporozoites of E. acervulina were needed to produce infections in the caeca and the embryo CAM respectively. The reproduction of both species in infections of chickens was similar and a high degree of cross-protection occurred.It was found that oocysts of E. mivati differed in size and shape depending upon whether they were produced from infections of embryos or chickens. When maintained by passage in chickens they assumed size and shape characteristics of E. acervulina.These findings, with the known similarity of the life-cycle stages, pathogenicity and pathology, indicate that E. mivati is not sufficiently different from E. acervulina to be a distinct species. It is suggested that it is best referred to as E. acervulina var. mivati.
Egg size and form as taxonomic criteria in Diphyllobothrium (Cestoda, Pseudophyllidea)
Authors: Andersen Karin , Halvorsen Odd 
Published: June 2009

SummaryThe size and form (length, width, and length: width ratio) of eggs of Diphyllobothrium dendriticum, D. ditremum and D. laturn vary considerably among individual worms within each species. The size of eggs varies with host species and a decrease in egg size with increasing intensity of infestation is indicated. The egg size of D. laturn increases during the first 10–12 days of egg production. For single worm infections in golden hamsters the mean egg length and width of D. ditremum are significantly smaller than the corresponding means of D. dendriticum and D. latum, while D. latum has significantly wider eggs than D. dendriticum. As taxonomic characteristics, egg size and form may contribute to species delimitation at the population level. For identification at the individual level the best possible accuracy is about 80%. This accuracy is considerably reduced when variation in host species and intensities of infestations are introduced. Scanning electron microscope studies did not reveal any differences among eggs of the three species.
Morphological and histochemical obervations on the ovarian balls of Centrorhynchus corvi (Acanthocephala)
Authors: Parshad V. R. , Guraya S. S. 
Published: June 2009

Unlike in other acanthocephalans, the overian balls of Centrorhynchus corvi are complex and are composed of 24–30 ovarian ball units. Each ovarian ball unit consists of three structural and functional units – the oogonial syncytium, developing oogenetic cells and the supporting syncytium – complementary to the ovarian balls of other acanthocephalans. Three metamorphic stages of the nuclei in the oogonial syncytium are described, depending on the nuclear morphology, chromatin structure and appearance of the nucleolus. Third-stage nuclei bulge out at the periphery of the oogonial syncytium and are surrounded by its cytoplasm and a thin membrane. Ultimately these are separated from the oogonial syncytium to from oogonia containing small amounts of cytoplasmic components derived from the oogonial syncytium. Nuclei of the young oogonia, oognia at the budding stage, and 3rd-stage nuclei of the oogonial syncytium all possess nucleoli and are similar also in their nuclear dimensions and cytochemical affinities. Nuclear resemblances, and cytoplasmic similarities of the oogonia and oogonial syncytium with regard to the presence of lipids, RNA and proteins support the concept of the origin of oogonia from the oogonial syncytium.The free oogonia divide mitotically in the cellular zone where they undergo a single mitotic division and the resulting oocytes enter the prophase of meiosis. I. The meiotic primary oocytes in contrast to the permeiotic primary oocytes of other acanthoscephalans enter the growth phase which is closely accompanied by the accumulation of various ooplasmic components such as basophilic yolk nucleus which is composed of RNA, proteins, lipoproteins and phospholipids. Histochemical features of the oogonial and supporting syncytium are described.
The effect of natural worm loss on the estimate of anthelmintic activity in an anthelmintic test with Haemonchus contortus
Authors: Turton J. A. , Clark C. J. 
Published: June 2009

An anthelmintic test was carried out in lambs against fourth-stage larvae of Haemonchus contortus to determine whether a natural loss of worms from either untreated control animals or from animals treated with anthelmintic affected the estimated activity of the anthelmintic.Thirty-two lambs were each infected with 1500 larvae of H. contortus on 4 consecutive days and divided into 4 groups of 8 animals. Two groups of lambs were treated with anthelmintic on day 7, the first group being slaughtered on day 9 and the second on day 29. An untreated control group was slaughtered 7 days after infection and a second control group was killed 29 days after infection.The numbers of worms recovered indicated that in the untreated control lambs there was an estimated daily loss of about 7% of the parasite population between the first day of infection and day 29, and in the lambs given anthelmintic an estimated daily loss of about 2% of the worm population was indicated between days 9 and 29. If the rate of worm loss is not the same in the untreated control hosts and in the treated animals, the estimate of anthelmintic efficacy will vary according to the time of autopsy. To minimize the possibility of an incorrect result occurring in an anthelmintic trial due to a natural loss of worms, it is recommended that the untreated control and the treated lambs are slaughtered on the same day, and that the autopsy is carried out as soon as possible after anthelmintic therapy.