Endosymbiont diversity in natural populations of Tetranychus mites is rapidly lost under laboratory conditions

AbstractReproduction and shell growth in two snail species from the family Clausiliidae differing in reproductive strategies were examined under laboratory conditions. The specimens of the oviparous species Clausilia bidentata and the ovoviviparous species Ruthenica filograna were collected in natural populations coexisting in the same area. The total time of shell growth in the specimens of C. bidentata ranged from 77 to 178 days and in R. filograna specimens ranged between 108 and 194 days. Under breeding conditions the species differed in the timing of reproduction and mortality. However the proportion of the number of surviving specimens to the number of eggs laid by C. bidentata or juveniles born by R. filograna proved to be similar.

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Maintenance and Productivity of a Lutzomyia longipalpis (Diptera: Psychodidae) Colony from an Area Endemic for Visceral and Cutaneous Leishmaniasis in Northeastern Brazil

Journal of Medical Entomology ◽

10.1093/jme/tjab053 ◽

2021 ◽

Author(s):

Rosa Cristina Ribeiro da Silva ◽

Léo Nava Piorsky Dominici Cruz ◽

João Manoel da Silva Coutinho ◽

Núrzia Cristina Correia Santana ◽

José Manuel Macário Rebêlo

Keyword(s):

Vector Competence ◽

Natural Populations ◽

Northeastern Brazil ◽

Sand Fly ◽

Lutzomyia Longipalpis ◽

Infection Rates ◽

Laboratory Conditions ◽

Leishmania Spp ◽

Cutaneous Form ◽

Males And Females

Abstract Studies on experimental sand fly infection require the availability of colonies and laboratory conditions. In Brazil, Lutzomyia longipalpis (Diptera: Psychodidae) (Lutz and Neiva 1912) is responsible for the highest infection rates by Leishmania spp. and this species is one of the most suitable species for laboratory colonization. In this study, we describe a method for growing Lu. longipalpis in laboratory conditions (10 generations) from natural populations sampled from a region of high endemicity for visceral leishmaniasis in the state of Maranhão, Northeastern Brazil. Using two methods (individualized or grouped females), the colony’s highest productivity occurred in the first four generations, where all stages presented with high frequency. Nonviable eggs represented more than 50% of the total eggs produced by engorged females, while pupae were more resistant to fungal contamination, with a mortality rate of only 2%. In both methods, there was a predominance of female emergence; however, the ratio between males and females did not show significant differences, IF (P = 0.8023) and GF (P = 0.1831). Using the method of individualized females, the F4 generation took the longest to appear (234 d; 64 ± 57 d); by grouped females, F3 took the longest to appear (102 d; 47 ± 20 d). This method provides sufficient numbers of insects to perform vector competence tests for Leishmania spp. that cause the cutaneous form of leishmaniasis, usually found in Lu. longipalpis sampled from the study location.

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Effects of genomic instability in populations of Drosophilae melanogaster from regions of Ukraine with different radiation impact factors

Nuclear Physics and Atomic Energy ◽

10.15407/jnpae2021.02.174 ◽

2021 ◽

Vol 22 (2) ◽

pp. 174-181

Author(s):

A.P. Kravets ◽

◽

D.A. Sokolova ◽

N.L. Kovalchuk

Keyword(s):

Genomic Instability ◽

Gonadal Dysgenesis ◽

Natural Populations ◽

Mobile Elements ◽

Impact Factors ◽

Chronic Irradiation ◽

Laboratory Conditions ◽

The City ◽

Accumulated Dose ◽

Low Rate

Differences in the gonadal dysgenesis frequency as an indicator of the activation of mobile elements were revealed in F1-descendants of natural populations of Drosophіla melanogaster, selected from regions of different radiation impact. Under conditions of additional low-rate chronic irradiation in laboratory conditions for 10 generations, significant differences in changes in the level and dynamics of this indicator were established depending on the accumulated dose of Drosophila populations from the city of Netishin (Khmelnytskyi NPP) and Magarach city.

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Observations on rearing damselflies under laboratory conditions

Animal Biology ◽

10.1163/157075603769682567 ◽

2003 ◽

Vol 53 (1) ◽

pp. 37-45 ◽

Cited By ~ 27

Author(s):

Hans van Gossum ◽

Adolfo Cordero Rivera ◽

Rosana Sánchez

Keyword(s):

Life Cycle ◽

Natural Populations ◽

Low Density ◽

Entire Life ◽

Entire Life Cycle ◽

Laboratory Conditions ◽

Sufficient Food

AbstractRearing damselflies under laboratory conditions is a promising means of solving a variety of biological questions. Therefore, in order to improve the success of future researchers we felt the need to indicate potential difficulties in carrying out rearing experiments. Laboratory crosses were obtained using virgin animals originating from natural populations in Belgium and Spain. Resulting offspring was maintained, under laboratory conditions, in small aquaria until emergence and in insectaries as adults. Our results show that keeping damselflies during their entire life cycle under artificial conditions can be very difficult. We suggest that future researchers should change water regularly, supply sufficient food, and rear animals at low density or even individually. Furthermore, suggestions are given on type of food, advisable laboratory conditions and female oviposition methodology.

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Gut-Associated Lymphoid Tissue in Microtus montanus from Natural Populations

The UW National Parks Service Research Station Annual Reports ◽

10.13001/uwnpsrc.2000.3421 ◽

2000 ◽

Vol 24 ◽

pp. 69-71

Author(s):

Aelita Pinter

Keyword(s):

Immune System ◽

Population Density ◽

Lymphoid Tissue ◽

Environmental Variables ◽

Natural Populations ◽

Natural Conditions ◽

Microtus Montanus ◽

Laboratory Conditions ◽

Lymphoid System ◽

And Function

Impaired immunocompetence may contribute to the multiannual fluctuations ("cycles") in population density of arvicoline rodents (Mihok et al. 1985, Pinter 1988, Lochmiller et al. 1993). In a variety of species environmental variables influence at least one component of the immune system, the gut-associated lymphoid system, GALT (Lopez et al. 1985, Li et al. 1995). Preliminary laboratory observations suggest that the development of GALT in Microtus montanus can be influenced by such factors as age and diet (Smith and Pinter 2000). However, these observations are from captive-bred voles, maintained on a synthetic laboratory diet, under strictly controlled laboratory conditions. The complexity and abundance of variables under natural conditions must influence the development and function of GALT- yet, nothing is known about it from Microtus montanus under natural conditions. The purpose of this study was essentially twofold: (1) to describe the morphometries of GALT in wild-caught M. montanus, and (2) to characterize the morphometric changes that occur in GALT of these animals as a function of their age, sex, and the season of the year.

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Novel Chlamydiae and Amoebophilus endosymbionts are prevalent in wild isolates of the model social amoebae Dictyostelium discoideum

10.1101/2020.09.30.320895 ◽

2020 ◽

Author(s):

Tamara S. Haselkorn ◽

Daniela Jimenez ◽

Usman Bashir ◽

Eleni Sallinger ◽

David C. Queller ◽

...

Keyword(s):

Dictyostelium Discoideum ◽

Natural Populations ◽

Model Organism ◽

Future Research ◽

Bacterial Strains ◽

Symbiotic Relationships ◽

Laboratory Conditions ◽

Natural Isolates ◽

History Of ◽

Large Survey

SummaryAmoebae interact with bacteria in diverse and multifaceted ways. Amoeba predation can serve as a selective pressure for the development of bacterial virulence traits. Bacteria may also adapt to life inside amoebae, resulting in symbiotic relationships (pathogenic or mutualistic). Indeed, amoebae are often infected with bacterial endosymbionts. Acanthamoeba and Hartmannella harbor symbionts from five distinct lineages within the Proteobacteria, Bacteroidetes, and Chlamydiae. Here, we PCR-screened an extensive collection of Dictyostelium discoideum wild isolates for the presence of bacterial symbionts. For the first time we found that obligate symbionts are surprisingly common in this highly-studied amoeba species, identified in 42% of screened isolates (N=730). Members of the environmental Chlamydiae are particularly prevalent. These strains are novel and phylogenetically distinct. We also found Amoebophilus symbionts in 8% of screened isolates (N=730). Under laboratory conditions, antibiotic-cured amoebae behave similarly to their endosymbiont-infected counterparts, suggesting that endosymbionts do not significantly impact host fitness, at least in the laboratory. We found several natural isolates were co-infected with different endosymbionts. The high prevalence and novelty of amoeba endosymbiont clades in the model organism D. discoideum opens the door to future research on the significance and mechanisms of amoeba-symbiont interactions.Significance statementIn a large survey across the eastern US, we identify the presence and prevalence of novel strains of obligate intracellular symbionts from within the Chlamydiae, Amoebophilus, and Procabacter lineages in natural populations of the social amoeba Dictyostelium discoideum. We demonstrate that these symbionts do not affect amoeba fitness under standard laboratory conditions. High prevalences in natural populations and some non-random co-infection patterns suggest that these symbionts have environmental context-dependent effects. The presence of these novel bacterial strains that are highly diverged from known amoeba endosymbionts provides an opportunity to study host specificity and host-symbiont interactions in the well-studied D. discoideum model organism. It opens the door for exploring the evolutionary history of these widespread obligate symbionts that are associated with a large variety of hosts.

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High-voltage electron microscopy of maxillary gland of spirochete-infected brine shrimp: lesion of efferent tubule

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100103875 ◽

1988 ◽

Vol 46 ◽

pp. 362-363

Author(s):

G. E. Tyson ◽

M. J. Song

Keyword(s):

Electron Microscopy ◽

High Voltage ◽

Brine Shrimp ◽

Natural Populations ◽

Three Dimensional ◽

Dimensional Structure ◽

High Voltage Electron Microscopy ◽

Voltage Electron ◽

High Voltage Electron ◽

Infected Adult

Natural populations of the brine shrimp, Artemia, may possess spirochete- infected animals in low numbers. The ultrastructure of Artemia's spirochete has been described by conventional transmission electron microscopy. In infected shrimp, spirochetal cells were abundant in the blood and also occurred intra- and extracellularly in the three organs examined, i.e. the maxillary gland (segmental excretory organ), the integument, and certain muscles The efferent-tubule region of the maxillary gland possessed a distinctive lesion comprised of a group of spirochetes, together with numerous small vesicles, situated in a cave-like indentation of the base of the tubule epithelium. in some instances the basal lamina at a lesion site was clearly discontinuous. High-voltage electron microscopy has now been used to study lesions of the efferent tubule, with the aim of understanding better their three-dimensional structure.Tissue from one maxillary gland of an infected, adult, female brine shrimp was used for HVEM study.

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Effect of acid deposition on trichome morphology and dogwood anthracnose biology

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100124604 ◽

1992 ◽

Vol 50 (1) ◽

pp. 840-841

Author(s):

Kyle T. Thornham ◽

R. Jay Stipes ◽

Randolph L. Grayson

Keyword(s):

Acid Deposition ◽

Disease Incidence ◽

Natural Populations ◽

Tree Disease ◽

Flowering Dogwood ◽

Discula Destructiva ◽

Disease Induction ◽

Dogwood Anthracnose ◽

Trichome Morphology ◽

Precipitation Events

Dogwood anthracnose, caused by Discula destructiva (1), is another new catastrophic tree disease that has ravaged natural populations of the flowering dogwood (Cornus florida) in the Appalachians over the past 15 years, and the epidemic is prognosticated to continue (2). An estimated 9.5 million acres have been affected, primarily in the Appalachian Mountains, from VA southwards, alone, and an estimated 50% of all dogwoods in PA have been killed. Since acid deposition has been linked experimentally with disease induction, and since the disease incidence and severity are more pronounced at higher elevations where lower pH precipitation events occur, we investigated the effect of acidic foliar sprays on moiphologic changes in the foliar cuticle and trichomes (3), the initial sites of infection and foci of Discula sporulation.

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