The Bionomics of Lema melanopa, L. (Criocerinae), in Great Britain

1929 ◽  
Vol 20 (1) ◽  
pp. 5-14 ◽  
Author(s):  
W. E. H. Hodson
Keyword(s):  
Life History ◽  
Life Cycle ◽  
Great Britain ◽  
Control Measures ◽  
Cereal Crops ◽  
Cultural Methods ◽  
Total Control ◽  
Previous Account ◽  
Larval Parasites ◽  
Do So

The beetle, Lema melanopa, is a serious pest of cereal crops in certain areas of Europe and is becoming increasingly common on cereals in Britain. A survey of the literature indicates that the life-history differs in various localities, and no previous account has been given of the life-history in this country.The life-cycle in Britain is briefly as follows. The adult beetles emerge from hibernation in April, mate and commence to oviposit towards the end of May. Oviposition continues for nearly two months, and adults commence to emerge early in July and continue to do so until September. There is no indication that a second brood occurs, although the climate would permit of one.The adults feed freely after emergence, but largely on grasses, prior to hibernating in November. In the spring they feed almost exclusively on the leaves of young cereals. The larvae feed principally on cereals. Adults tend to be gregarious and are very long-lived, numbers living over a second winter.Two larval parasites occur in Britain and further information concerning these is being obtained. Of all larvae collected in the field 25 per cent. were found to be parasitised.The loss of crop sustained as a result of attack by this pest amounts on the Continent, in extreme cases, to as much as 50 per cent. of the total. Control measures consist of cultural methods, spraying and dusting. Certain of these might be adapted for use in this country with reasonable hope of success.

Life history and pathogenicity of Eimeria adenoeides Moore & Brown, 1951, in the turkey poult

Parasitology ◽  
1958 ◽  
Vol 48 (1-2) ◽  
pp. 70-88 ◽  
Author(s):  
M. J. Clarkson
Keyword(s):  
Life History ◽  
Life Cycle ◽  
Great Britain ◽  
General Pattern ◽  
Blood Picture ◽  
Highly Pathogenic ◽  
Turkey Poult ◽  
Turkey Poults ◽  
Cell Inoculation ◽  
Microscopic Pathology

The life cycle and pathogenicity of a strain of Eimeria isolated in Great Britain from turkey poults by single cell inoculation are described and, using the criteria laid down by Tyzzer, the species is identified as E. adenoeides.The life cycle is of the same general pattern as in other Eimeria species, consisting of two asexual and one sexual generations.The organism is highly pathogenic for young poults, a dose of 200,000 oocysts producing 100 % mortality in 3-week-old birds and smaller doses causing reduced weight gain. Birds 11 weeks old resisted a dose of 3 million oocysts.The gross and microscopic pathology of the infection is described. No changes were found in the blood picture.

The life history and pathogenicity of Eimeria Meleagrimitis Tyzzer 1929, in the turkey poult

Parasitology ◽  
1959 ◽  
Vol 49 (1-2) ◽  
pp. 70-82 ◽  
Author(s):  
M. J. Clarkson
Keyword(s):  
Life History ◽  
Life Cycle ◽  
Great Britain ◽  
High Mortality ◽  
Pure Strain ◽  
Turkey Poult ◽  
Turkey Poults ◽  
Loss Of Weight ◽  
Sexual Generation

The life cycle and pathogenicity are described of a pure strain of Eimeria isolated from turkey poults in Great Britain and identified as E. meleagrimitis.There were three schizogony cycles followed by a sexual generation.The coccidium produced a high mortality and loss of weight in young poults.An age resistance developed by the time the poults were 8–10 weeks of age.The pathology of the infection is described.

scholarly journals Wider-community Segregation and the Effect of Neighbourhood Ethnic Diversity on Social Capital: An Investigation into Intra-Neighbourhood Trust in Great Britain and London

Sociology ◽  
2016 ◽  
Vol 51 (5) ◽  
pp. 1011-1033 ◽  
Author(s):  
James Laurence
Keyword(s):  
Social Capital ◽  
Great Britain ◽  
Ethnic Diversity ◽  
Linear Models ◽  
Critical Role ◽  
Hierarchical Linear Models ◽  
Negatively Associated ◽  
Community Segregation ◽  
Do So

Extensive research has demonstrated that neighbourhood ethnic diversity is negatively associated with intra-neighbourhood social capital. This study explores the role of segregation and integration in this relationship. To do so it applies three-level hierarchical linear models to two sets of data from across Great Britain and within London, and examines how segregation across the wider-community in which a neighbourhood is nested impacts trust amongst neighbours. This study replicates the increasingly ubiquitous finding that neighbourhood diversity is negatively associated with neighbour-trust. However, we demonstrate that this relationship is highly dependent on the level of segregation across the wider-community in which a neighbourhood is nested. Increasing neighbourhood diversity only negatively impacts neighbour-trust when nested in more segregated wider-communities. Individuals living in diverse neighbourhoods nested within integrated wider-communities experience no trust-penalty. These findings show that segregation plays a critical role in the neighbourhood diversity/trust relationship, and that its absence from the literature biases our understanding of how ethnic diversity affects social cohesion.

Production of uredinia and telia by stalactiform blister rust in British Columbia

1993 ◽  
Vol 71 (3) ◽  
pp. 519-521 ◽  
Author(s):  
B. J. van der Kamp
Keyword(s):  
British Columbia ◽  
Life Cycle ◽  
Key Words ◽  
Alternate Host ◽  
Alternate Hosts ◽  
Blister Rust ◽  
Dry Areas ◽  
Do So

Records of uredinia and telia production on the alternate hosts of Cronartium coleosporioides in British Columbia and inoculation of Castilleja miniata with aeciospores collected from various locations showed that rust isolates from dry areas of the interior of British Columbia do not produce uredinia and may have lost the ability to do so. Collections from somewhat wetter areas produced uredinia or mixtures of uredinia and telia immediately following aeciospore inoculations, and field collections from such areas in June commonly had mixtures of uredinia and telia. Loss of the uredinial stage may be a response to climates that are often unsuitable for the spread or survival of the rust on the alternate host. Key words: stalactiform rust, uredinia, telia, rust life cycle.

The cattle lice of Great Britain Part I. Biology, with special reference to Haematopinus eurysternus

Parasitology ◽  
1941 ◽  
Vol 33 (3) ◽  
pp. 331-342 ◽  
Author(s):  
H. J. Craufurd-Benson
Keyword(s):  
Life Cycle ◽  
Great Britain ◽  
Special Reference ◽  
Incubation Period ◽  
Air Temperature ◽  
Average Length ◽  
Starvation Period ◽  
Complete Life Cycle ◽  
Threshold Of Development ◽  
Minimum Air Temperature

1. The geographical distribution of cattle lice in Britain is recorded in detail. Bovicola bovis is the commonest and most widely distributed species in Britain.2. The incubation period for the eggs was found to be: Haematopinus eurysternus, 9–19 days (av. 12); Bovicola bovis, 7–10 days (av. 8); Linognathus vitula, 10–13 days; Solenopotes capillatus, 10–13 days. With eggs of H. eurysternus it was found that the higher the minimum air temperature the shorter was the incubation period.3. In H. eurysternus the average length of the instars was: 1st, 4 days; 2nd, 4 days; 3rd, 4 days; pre-oviposition period, 3–4 days. The average time for the complete life cycle, egg to egg, was 28 days.4. The maximum longevity of H. eurysternus on the host was: males, 10 days; females, 16 days. No males or females of H. eurysternus survived a starvation period of 72 hr. at 20° C. and R.H. 70 or 0–10° C. and R.H. 70–85; but some nymphs survived this period at 20° C. and R.H. 70, but none survived 96 hr. starvation.5. The maximum number of eggs recorded for one female was 24; and eggs were laid at the rate of 1–4 a day.6. The threshold of development of the eggs of H. eurysternus appears to be about 27·5° C.

The Life History and Habits of Chrysomela crotchi Brown (Coleoptera: Chrysomelidae) in Northwestern Ontario

1965 ◽  
Vol 97 (5) ◽  
pp. 541-549 ◽  
Author(s):  
E. P. Smereka
Keyword(s):  
Life History ◽  
Adult Stage ◽  
Egg Mass ◽  
Predator Species ◽  
Control Factors ◽  
Northwestern Ontario ◽  
History Of ◽  
Males And Females ◽  
Overwintering Mortality ◽  
Larval Parasites

AbstractThe life history of Chrysomela crotchi, a univoltine species commonly found on trembling aspen, was studied in northwestern Ontario from 1959 to 1962. The most striking feature of its life history was the longevity of adults, which were capable of overwintering two successive years. Overwintered adults became active and began feeding in late May, and oviposition occurred from early June to late July. The incubation period was approximately 10 days and the three larval instars required approximately one month for development to the adult stage.Females laid more eggs during their second season and the highest number laid was 326. The number of eggs in an egg mass averaged 37.6, and the average interval between the deposition of egg masses was 4 days. Males and females mated more than once, but only one mating was necessary for a female to produce viable eggs throughout the season. Males were capable of fertilizing more than one female and remained potent for more than one season.Parasitism was low, and only two species of larval parasites were reared. Several predator species were observed preying on the immature stages. Predation and overwintering mortality appeared to be the most important control factors.

The Output of First Stage Larvae by Cats Infested with Aelurostrongylus abstrusus

1968 ◽  
Vol 42 (3-4) ◽  
pp. 295-298 ◽  
Author(s):  
J. M. Hamilton ◽  
A. W. McCaw
Keyword(s):  
Life Cycle ◽  
Great Britain ◽  
Intermediate Host ◽  
World Wide ◽  
Wide Distribution ◽  
Clinical Disease ◽  
Complex Life Cycle ◽  
Patent Period ◽  
Aelurostrongylus Abstrusus

Aelurostrongylus abstrusus, the lungworm of the cat, has a world wide distribution and has been reported from countries as far apart as America, Great Britain and Palestine. It has a complex life cycle insofar as a molluscan intermediate host is essential and it is possible that auxiliary hosts also play an important part. In Britain, the incidence of active infestation of cats with the parasite has been recorded as 19·4% (Lewis, 1927) and 6·6% (Hamilton, 1966) but the latter author found that, generally, the clinical disease produced by the parasite was of a mild nature. It is known that the average patent period of the infestation in the cat is 8–13 weeks and it seems likely that, in that time, a considerable number of first stage larvae would be evacuated. Information on that point is not available and the object of the following experiment was to ascertain the number of larvae produced by cats during the course of a typical infestation.

The life-cycle of Echinoparyphium hydromyos sp.nov. (Digenea: Echinostomatidae) from the Australian water-rat

Parasitology ◽  
1967 ◽  
Vol 57 (1) ◽  
pp. 19-30 ◽  
Author(s):  
L. Madeline Angel
Keyword(s):  
Life History ◽  
Life Cycle ◽  
Experimental Work ◽  
Field Work ◽  
Type Material ◽  
South Australian Museum ◽  
The South ◽  
Australian Water ◽  
Australian Museum ◽  
Hydromys Chrysogaster

Echinoparyphium hydromyos sp.nov. with forty-five collar spines is described from the Australian water rat, Hydromys chrysogaster Geoffr.The cercaria occurs naturally in Plananisus isingi (Cotton & Godfrey), and all stages in the life-history have been demonstrated experimentally.Encystation occurs in the kidneys of tadpoles.The adult is most closely related to Echinoparyphium recurvatum (Linstow). It differs from this in its greater number of eggs and in its life-history. E. recurvatum occurs predominantly in birds, and is rarely found naturally in mammals. E. hydromyos has been found only in a mammal.Cercaria echinoparyphii hydromyos is compared with C. clelandae Johnston and Angel; it differs from the latter in the ‘compound’ nature of the excretory granules. The adult of C. clelandae has not been demonstrated in spite of a number of experiments to determine it.Type material has been deposited in the South Australian Museum.I wish to acknowledge the help given by my colleague, Patricia M. Thomas, in field work and in other ways, and by Mr Ian Smith, of this department, in the experimental work on life-history studies.

scholarly journals Analysis of a mosquito life cycle model

2021 ◽  
Vol Volume 34 - 2020 - Special... ◽  
Author(s):  
Albert Kouchéré ◽  
Hamadjam Abboubakar ◽  
Irepran Damakoa
Keyword(s):  
Life Cycle ◽  
Sterile Insect Technique ◽  
Deterministic Model ◽  
Communicable Disease ◽  
Control Measures ◽  
Reproductive Number ◽  
Gonotrophic Cycle ◽  
Complete Life Cycle ◽  
Trivial Equilibrium ◽  
International Audience

International audience The gonotrophic cycle of mosquitoes conditions the frequency of mosquito-human contacts. The knowledge of this important phenomenon in the mosquito life cycle is a fundamental element in the epidemiological analysis of a communicable disease such as mosquito-borne diseases.In this work, we analyze a deterministic model of the complete life cycle of mosquitoes which takes into account the principal phases of female mosquitoes' gonotrophic cycle, and the Sterile Insect technique combined with the use of insecticide as control measures to fight the proliferation of mosquitoes. We compute the corresponding mosquito reproductive number N ∗ and prove the global asymptotic stability of trivial equilibrium. We prove that the model admits two non-trivial equilibria whenever N^{∗} is greater than another threshold, N_c, which the total number of sterile mosquitoes depends on. Numerical simulations, using mosquito parameters of the Aedes species, are carried out to illustrate our analytical results and permit to show that the strategy which consists in combining the sterile insect technique with adulticides, when it is well done, effectively combats the proliferation of mosquitoes.

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