THE KARYOTYPE OF ECHINOCOCCUS MULTILOCULARIS (CESTODA: TAENIIDAE)

1981 ◽  
Vol 23 (1) ◽  
pp. 151-154 ◽  
Author(s):  
V. R. Rausch ◽  
R. L. Rausch
Keyword(s):  
Larval Stage ◽  
Echinococcus Multilocularis ◽  
Adult Stage ◽  
Fundamental Number

The chromosomes of Echinococcus multilocularis Leuckart, 1863 have been described, based on components of cells from the adult stage and the larval stage of the cestode. Chromosomal complements of 2n = 18, n = 9 were confirmed. The fundamental number of chromosomal arms was 24. Karyograms are presented, in which the 18 elements are grouped according to arm-ratios and size. An idiogram of G-bands is included.

scholarly journals Translation initiation in Drosophila melanogaster is reduced by mutations upstream of the AUG initiator codon.

1991 ◽  
Vol 11 (4) ◽  
pp. 2149-2153 ◽  
Author(s):  
Y Feng ◽  
L E Gunter ◽  
E L Organ ◽  
D R Cavener
Keyword(s):  
Translation Initiation ◽  
Larval Stage ◽  
Developmental Stages ◽  
Germ Line ◽  
Adult Stage ◽  
Mutant Gene ◽  
Start Codon ◽  
Fold Reduction

The importance to in vivo translation of sequences immediately upstream of the Drosophila alcohol dehydrogenase (Adh) start codon was examined at two developmental stages. Mutations were introduced into the Adh gene in vitro, and the mutant gene was inserted into the genome via germ line transformation. An A-to-T substitution at the -3 position did not affect relative translation rates of the ADH protein at the second-instar larval stage but resulted in a 2.4-fold drop in translation of ADH at the adult stage. A second mutant gene, containing five mutations in the region -1 to -9, was designed to completely block translation initiation. However, transformant lines bearing these mutations still exhibit detectable ADH, albeit at substantially reduced levels. The average fold reduction at the second-instar larval stage was 5.9, while at the adult stage a 12.5-fold reduction was observed.

scholarly journals Fumigant toxicity of some essential oils against Red Flour Beetles, Tribolium castaneum (Herbst) and its safety to mammals

2020 ◽  
Vol 80 (4) ◽  
pp. 769-776
Author(s):  
T. M. Sileem ◽  
A. L. Mehany ◽  
R. S. Hassan
Keyword(s):  
Essential Oil ◽  
Essential Oils ◽  
Tribolium Castaneum ◽  
Larval Stage ◽  
Adult Stage ◽  
Lethal Concentration ◽  
Median Lethal Concentration ◽  
Histological Changes ◽  
Garlic Oil ◽  
Garlic Essential Oil

Abstract Fumigant activities for three essential oils; Garlic oil (Allium sativum L); Chili pepper (Capsicum annuum L.) and Nigella (Nigella sativa L.) were assessed at different concentrations against the adult and 20-days old larval stages of Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) in the laboratory. The accumulative mortality was observed at different exposure periods (3, 5 and 7 days). The residual effect of garlic oil that was the effective oil, on the treated wheat grains was evaluated with respect to histological changes in the liver, kidney, and stomach of rat fed on this treated wheat. The results showed that the mortality rates of treated stages increased with increasing the time of fumigation treatment. Moreover the highest essential oils toxicity at the Median lethal concentration (LC50) values for exposure periods (3, 5 and 7 days) to fumigation were (126, 53, and 47 mg/L air) for adult stage and were (79, 62, and 41 mg/L air) for larval stage, respectively in the case of Garlic oil treatment. While, the lowest essential oils effective was Nigella oil at the Median lethal concentration (LC50) values for exposure periods (3, 5 and 7 days) to fumigation were (3594, 629, and 335 mg/L air) for adult stage and were (1040, 416, and 227 mg/L air) for larval stage, respectively. The toxicity effect of various essential oils against adults and larvae of T. castaneum at the LC50at 7 days fumigation could be arranged in descending order as follows: Garlic oil, Chili pepper oil, and Nigella oil. The histological changes showed that the organs slightly affected at the fumigation for 3 days. It may be concluded that the garlic essential oil is the good effective fumigant to control T. castaneum in the stored products and it recommended that the fumigation period does not exceed 3 days. The garlic essential oil has the potential for applications in IPM programs for stored-grain pests because of its high volatility and fumigant activity and its safety.

scholarly journals Chironomidae: Biology, Ecology and Systematics

2021 ◽  
Author(s):  
Zerguine Karima
Keyword(s):  
Life Cycle ◽  
Larval Stage ◽  
Adult Stage ◽  
Aquatic Environments ◽  
Biting Midges ◽  
Important Family ◽  
Theoretical Synthesis ◽  
The Family ◽  
The World ◽  
Holarctic Region

The family of Chironomidae is a group of Diptera insects belonging to the suborder of Nematocera, commonly called “non-biting midges” in the adult stage and “bloodworms” in the larval stage. The Chironomidae are often the most abundant group of macroinvertebrates, in number of species and individuals, encountered in all aquatic environments of freshwater, brackish, terrestrial and even the sea. Likewise, Chironomidae occur in all the continents. The Chironomidae family is divided into 11 sub-families that have diffrent ecological statues. Despite the wealth of data on Chironomidae in the Holarctic region, other parts of the world are poorly studied and few guides to identifying Chironomidae have been produced. This chapter includes a theoretical synthesis on the Chironomidae, it deals with the Biology (life cycle and description of different stages), description of all subfamilies and the ecology of this important family of Diptera.

Hepatic Alveolar Echinococcosis

2021 ◽  
Author(s):  
Solange Bresson-Hadni ◽  
Laurent Spahr ◽  
François Chappuis
Keyword(s):  
Access To Care ◽  
Surgical Resection ◽  
Larval Stage ◽  
Echinococcus Multilocularis ◽  
Gold Standard ◽  
Diagnostic Procedure ◽  
Alveolar Echinococcosis ◽  
Opportunistic Infections ◽  
First Line ◽  
Hepatic Alveolar Echinococcosis

AbstractHepatic alveolar echinococcosis (HAE) is a rare but severe zoonosis caused by the pseudotumoral intrahepatic development of the larval stage of the tapeworm Echinococcus multilocularis. HAE is present only in the Northern Hemisphere, predominantly in China. Currently, there is a significant resurgence of cases in historically endemic areas associated with emergence of HAE in countries not previously concerned. Today, in European countries, HAE is often discovered by chance; however, clinicians should be made aware of opportunistic infections that progressively emerged recently as a result of therapeutic or pathological immunosuppression. Ultrasonography is the key first-line diagnostic procedure, with specific serology providing confirmation in 95% of the cases. Albendazole, only parasitostatic, is the mainstay for treatment. Surgical resection, if feasible, is the gold standard for treatment, and more patients are currently eligible for this option because of an earlier diagnosis. The prognosis has considerably improved but remains poor in countries where access to care is less favorable.

SEASONAL DEVELOPMENT AND HABITS OF PSEUDOPITYOPHTHORUS SPP. (COLEOPTERA: SCOLYTIDAE) IN SOUTHERN OHIO

1969 ◽  
Vol 101 (3) ◽  
pp. 306-313 ◽  
Author(s):  
Charles O. Rexrode
Keyword(s):  
Larval Stage ◽  
Bark Beetles ◽  
Adult Stage ◽  
Average Length ◽  
Pupal Stage ◽  
Seasonal Development ◽  
Two Generations ◽  
Spring Emergence ◽  
Seasonal History ◽  
Initial Entry

AbstractDuring 1965–67, the seasonal history and habits of two oak bark beetles, Pseudopityophthorus minutissimus (Zimm.) and P. pruinosus (Eichhoff), were studied in 47 oaks, Quercus spp., in southern Ohio.All study trees were attacked and the male beetles made initial entry into the trees. The attack period per tree was usually 1–3 days, and the density of attack varied from 5 to 120 galleries 1 ft2 of surface area. Oviposition began as soon as egg gallery construction began, and the incubation period was about 5 days in the summer. The rate of egg gallery construction was about 0.2 in./day in mid-summer. The average length of the egg galleries was 1.9 cm and the average number of eggs per gallery was 41.5. Over 50% of the parent adults of both species re-emerged after egg gallery construction and oviposition. The re-emerging parent adults can attack, lay eggs, and re-emerge three times. The larval stage can last 25–247 days, the pupal stage 15–139 days, and the adult stage 7–198 days. The beetles can overwinter in every stage but the pupal stage. Spring emergence occurred 29 April in 1966 and 14 April in 1967, and in southern Ohio, two generations and a partial one occur each year.Trap trees were attacked 7–205 days and brood emergence lasted 58–329 days. The beetles can attack one tree three times.

An experimental investigation of the effects of selective predation by birds and parasitoid attack on the butterfly Danaus chrysippus (L.)

1984 ◽  
Vol 221 (1222) ◽  
pp. 31-51 ◽  
Keyword(s):  
Theoretical Model ◽  
Larval Stage ◽  
Relative Frequency ◽  
Adult Stage ◽  
The Other ◽  
Selective Predation ◽  
Bird Predation ◽  
Toxic Plants ◽  
Danaid Butterfly ◽  
Three Stages

Danaus chrysippus is a danaid butterfly commonly found throughout Africa. It feeds, in its larval stage, on species of milkweed (fam. Asclepiadacae). If the milkweed species has a high cardenolide content, then the larva as well as its pupa and the subsequent adult will be toxic to birds. If, however, the larva has fed on a species of milkweed with little or no cardenolide content, then it will be palatable to birds and so will the pupa and the adult. All the three stages (larval, pupa and adult), whether palatable or not, are subject to attack by birds. The larvae, on the other hand, also act as hosts to a large number of parasitoids. In this paper a theoretical model is described which incorporates the following three assumptions that have been verified experimentally: (i) female butterflies prefer to oviposition the species of plants on which they had developed; (ii) birds are able to distinguish between externally identical larvae from the shape of the plant on which the larvae are feeding; (iii) female parasitoids select, for oviposition, D. chrysippus larvae feeding on plants toxic to vertebrate predators. The simulations using the theoretical model predicts that parasitoids will prefer to lay their eggs in toxic larvae that are less likely to be predated by birds. This predation makes it advantageous for larvae to feed on non-toxic plants. This larval advantage is countered at the adult stage by bird predation. As one type of butterfly becomes too common, the other type will be at an advantage. The polymorphism for palatability is maintained primarily through selection at the larval stage and not by bird predation on the adult butterflies. The experimental data supporting the above assumptions are discussed. Computer simulation predicts the behaviour of birds and parasitoids as it affects the relative frequency of toxic and non-toxic butterflies.

scholarly journals Navigating infection risk during oviposition and larval foraging in a holometabolous insect

2017 ◽  
Author(s):  
Jonathon A. Siva-Jothy ◽  
Katy M. Monteith ◽  
Pedro F. Vale
Keyword(s):  
Larval Stage ◽  
Developmental Stages ◽  
Adult Stage ◽  
Life Stages ◽  
Holometabolous Insect ◽  
Fitness Consequences ◽  
Risk Of Exposure ◽  
Selection For ◽  
Complete Metamorphosis ◽  
Oviposition Sites

AbstractDeciding where to eat and raise offspring carries important fitness consequences for all animals, especially if foraging, feeding and reproduction increase the risk of exposure to pathogens. In insects with complete metamorphosis, foraging occurs mainly during the larval stage, while oviposition decisions are taken by adult-stage females. Selection for infection avoidance behaviours may therefore be developmentally uncoupled. Using a combination of experimental infections and behavioural choice assays, here we tested if Drosophila melanogaster fruit flies avoid potentially infectious environments at distinct developmental stages. When given conspecific fly carcasses as a food source, larval-stage flies did not discriminate between carcasses that were clean or infected with the pathogenic Drosophila C Virus (DCV), even though scavenging was a viable route of DCV transmission. Adult females however, discriminated between different oviposition sites, laying more eggs near a clean rather than an infectious carcass if they were healthy; DCV-infected females did not discriminate between the two environments. While potentially risky, laying eggs near potentially infectious carcasses was always preferred to sites containing only fly medium. Our findings suggest that infection avoidance can play an important role in how mothers provision their offspring, and underline the need to consider infection avoidance behaviours at multiple life-stages.

scholarly journals Study on the biology of groundnut bruchid, Caryedon serratus Olivier [Coleoptera: Bruchidae] on stored groundnut in Ganye area, Adamawa State, Nigeria

2020 ◽  
Vol 12 (3) ◽  
pp. 272-276
Author(s):  
C.S. Oaya
Keyword(s):  
Life Cycle ◽  
Larval Stage ◽  
Developmental Stages ◽  
Adult Stage ◽  
Pupal Stage ◽  
Male And Female ◽  
Incubation Stage ◽  
Caryedon Serratus ◽  
The Mean ◽  
Total Life

Abstract. Study on the biology of groundnut bruchid, Caryedon serratus Olivier was carried out in the Laboratory of the Department of Agricultural Technology, Adamawa State College of Agriculture, Ganye, Adamawa State from June to September, 2015. The sex of the bruchid (male and female) was assigned the sub-treatment while the period of development was the main treatment and was replicated three times. The work considered the pre-oviposition stage, incubation stage, larval stage, pupal stage, adult stage and the total life cycle of the bruchid (male and female). The experiment was carried out under Laboratory conditions at 30-35°C temperature and 70-90% relative humidity. After the experiment was established, weekly counting of the total number of eggs laid was carried out at intervals. The results showed that, the mean developmental stages in both female and male bruchids were: 6.50 and 6.00 days; 17.00 and 18.00 days; 13.50 and 13.50 days; 12.00 and 13.50 days; 48.00 and 50.00 days for incubation stage, larval stage, pupal stage, adult stage and total life cycle of the bruchids, respectively. Moreover, the mean pre-oviposition and oviposition stages in female adult bruchid were 1.50 and 5.50 days, respectively.

scholarly journals Drosophila larval epidermal cells only exhibit epidermal aging when they persist to the adult stage

2020 ◽  
Author(s):  
Yan Wang ◽  
Sirisha Burra ◽  
Michael J. Galko
Keyword(s):  
Larval Stage ◽  
Cell Membranes ◽  
Adult Stage ◽  
Body Plan ◽  
Epidermal Cells ◽  
The Body ◽  
Multinucleate Cells ◽  
Aging Program ◽  
Summary Statement ◽  
Complete Transformation

AbstractHolometabolous insects undergo a complete transformation of the body plan from the larval to the adult stage. In Drosophila, this transformation includes replacement of larval epidermal cells (LECs) by adult epidermal cells (AECs). AECs in Drosophila undergo a rapid and stereotyped aging program where they lose both cell membranes and nuclei. Whether LEC’s are capable of undergoing aging in a manner similar to AECs remains unknown. Here, we address this question in two ways. First, we looked for hallmarks of epidermal aging in larvae that have a greatly extended third instar and/or carry mutations that would cause premature epidermal aging at the adult stage. Such larvae, irrespective of genotype, did not show any of the signs of epidermal aging observed in the adult. Second, we developed a procedure to effect a heterochronic persistence of LECs into the adult epidermal sheet. LECs embedded within the adult epidermal sheet undergo clear signs of epidermal aging; they form multinucleate cells with each other and with the surrounding AECs on the same schedule as the AECs themselves. Our data reveals that epidermal aging in holometabolous Drosophila is a stage-specific phenomenon and that the capacity of LECs to respond to aging signals does exist.Summary StatementWe show that Drosophila larval epidermal cells do not age at the larval stage. They do, however, exhibit signs of aging if they persist into the adult.

scholarly journals Translation initiation in Drosophila melanogaster is reduced by mutations upstream of the AUG initiator codon

1991 ◽  
Vol 11 (4) ◽  
pp. 2149-2153
Author(s):  
Y Feng ◽  
L E Gunter ◽  
E L Organ ◽  
D R Cavener
Keyword(s):  
Translation Initiation ◽  
Larval Stage ◽  
Developmental Stages ◽  
Germ Line ◽  
Adult Stage ◽  
Mutant Gene ◽  
Start Codon ◽  
Fold Reduction

The importance to in vivo translation of sequences immediately upstream of the Drosophila alcohol dehydrogenase (Adh) start codon was examined at two developmental stages. Mutations were introduced into the Adh gene in vitro, and the mutant gene was inserted into the genome via germ line transformation. An A-to-T substitution at the -3 position did not affect relative translation rates of the ADH protein at the second-instar larval stage but resulted in a 2.4-fold drop in translation of ADH at the adult stage. A second mutant gene, containing five mutations in the region -1 to -9, was designed to completely block translation initiation. However, transformant lines bearing these mutations still exhibit detectable ADH, albeit at substantially reduced levels. The average fold reduction at the second-instar larval stage was 5.9, while at the adult stage a 12.5-fold reduction was observed.

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