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4042. Seasonal dynamics of Proteocephalus torulosus (Cestoda: Proteocephalidae) in barbel (Barbus barbus) from the Jihlava River, Czech Republic
- Creator:
- Scholz, T. and Moravec, F.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Cestoda, Proteocephalus torulosus, barbel, seasonal cycle, Czech Republic, and Sialis lutaria
- Language:
- English
- Description:
- The proteocephalid tapeworm Proteocephalus torulosus (Batsch, 1786) exhibited a marked seasonality in its occurrence and maturation in barbel (Barbus harhus L.) from the Jihlava River, South Moravia, Czech Republic. Recruitment took place in winter and early spring, growth and maturation in spring and gravid worms left the fish hosts in May; during summer and autumn, the parasite was almost absent from the fish population. Parasite burden was related to fish size, with larger barbel being more heavily infected than smaller ones.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4043. Seasonal occurrence and microhabitat specificity of Paradiplozoon ichthyoxanthon Avenant-Oldewage in Avenant-Oldewage et al., 2014 (Monogenea: Diplozoidae) infecting Labeobarbus aeneus (Burchell) (Teleostei: Cyprinidae) from the Vaal Dam, South Africa: water quality and host size as determining factors?
- Creator:
- Gilbert, Beric M and Avenant-Oldewage, Annemariè
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- ekologie, epidemiologie, ecology, epidemiology, Afrika jižní, Africa, Southern, ectoparasite, seasonality, smallmouth yellowfish, gill arch, 2, and 59
- Language:
- English
- Description:
- This is the first study detailing the microhabitat specificity of the monogenean parasite, Paradiplozoon ichthyoxanthon Avenant-Oldewage in Avenant-Oldewage et al., 2014. Samples of the monogenean were collected from the gills of the smallmouth yellowfish Labeobarbus aeneus (Burchell) from the Vaal Dam, South Africa, over four seasons with the use of gill nets. Host condition factor fluctuated between the different seasons, with the highest values recorded in summer. Adults and diporpas of P. ichthyoxanthon were found in all four seasons. Adult parasites predominantly infect the first gill arch, whereas diporpas were found on the second and fourth arches. In utero eggs were also found throughout the sampling seasons and their number negatively correlated with the condition factor of the host. The occurrence of adults and diporpas of P. ichthyoxanthon correlated with the size of the host but not the condition factor. Water quality of the study site also had little correlational relationship with the occurrence of the parasites and fluctuations were related to season. The main factor that may drive the microhabitat specificity of P. ichthyoxanthon is the flow of water over the surfaces of the gills and chances of the parasites becoming dislodged. Size of the attachment organs has also been shown to play a role in this specificity, because smaller attachment structures favour stronger holdfast to areas where flow might be stronger compared to larger attachment structures., Beric M. Gilbert, Annemariè Avenant-Oldewage., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
4044. Seasonal polyphenism in body size and juvenile development of the swallowtail butterfly Papilio xuthus (Lepidoptera: Papilionidae)
- Creator:
- Komata, Shinya and Sota, Teiji
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, motýli, otakárkovití, butterflies, Papilionidae, Papilio xuthus, seasonal polyphenism, body size variation, adaptive growth decision, protandry, temperature-size rule, time constraint, 2, and 59
- Language:
- English
- Description:
- Seasonal polyphenism in adults may be a season-specific adaptation of the adult stage and/or a by-product of adaptive plasticity of the juvenile stages. The swallowtail butterfly Papilio xuthus L. exhibits seasonal polyphenism controlled by photoperiod. Adults emerging in spring from pupae that spend winter in diapause have smaller bodies than adults emerging in summer from pupae that do not undergo diapause. Pupal diapause is induced by short-day conditions typical of autumn. To explore the interactive effects of temperature and developmental pathways on the variation in adult body size in P. xuthus, we reared larvae at two temperatures (20°C, 25°C) under two photoperiods (12L : 12D and 16L : 8D). Pupal weight and adult forewing length were greater in the generation that did not undergo diapause and were greater at 25°C than at 20°C. Thus, body size differences were greatest between the individuals that were reared at the longer day length and higher temperature and did not undergo diapause and those that were reared at the shorter day length and lower temperature and did undergo diapause. Unlike in other Lepidoptera, larvae of individuals that undergo diapause had shorter developmental times and higher growth rates than those that did not undergo diapause. This developmental plasticity may enable this butterfly to cope with the unpredictable length of the growing season prior to the onset of winter. Our results indicate that there are unexplored variations in the life history strategy of multivoltine Lepidoptera., Shinya Komata, Teiji Sota., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4045. Seasonal polyphenism in Eristalis pertinax (Diptera: Syrphidae)
- Creator:
- Mielczarek, Lukasz E., Oleksa, Andrzej, Meyza, Katarzyna, and Tofilski, Adam
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, dvoukřídlí, pestřenkovití, Diptera, Syrphidae, Eristalis pertinax, seasonal polyphenism, wing venation, allometry, 2, and 59
- Language:
- English
- Description:
- Eristalis pertinax varies seasonally, with the spring morph more hairy than the summer morph. We measured the size and the venation of the wings of the seasonal morphs. Wings of the spring morph were significantly larger than those of the summer morph and those of females were larger than those of males. There were also significant differences between the morphs in wing venation and their allometric relationship. The differences between sexes were larger than differences between seasonal morphs. The allometry can account for the sexual dimorphism but not seasonal dimorphism. The differences between seasonal morphs in wing shape were relatively large with very few intermediate individuals. The differences were comparable to those between two related species of Syrphidae. Genetic analyses based on markers in nuclear and mitochondrial genomes unequivocally revealed that spring and summer morphs of E. pertinax form a single population and should not be regarded as separate taxa. Thus seasonal variability in this species is a rare example of polyphenism in Diptera., Lukasz E. Mielczarek, Andrzej Oleksa, Katarzyna Meyza, Adam Tofilski., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4046. Seasonal prevalence of trematode cercariae in Clypeomorus bifasciata (Gastropoda: Prosobranchia) in Kuwait Bay
- Creator:
- Abdul-Salam, J., Sreelahta, B.S., and Ashkanani, H.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Clypeomorus bifasciata, cercariae, seasonal occurrence, and Kuwait
- Language:
- English
- Description:
- Of 14,431 Clypeomorus bifasciata Sowerby, 1855 collected from Kuwait Bay between November 1992 and October 1993, 718 (5.0%) were shedding a total of 12 morphologically distinguishable ‘types’ of cercariae: 1 cystocercous, 2 echinos-tome, 1 furcocystocercous, 3 magnacercous, 2 megalurous, 1 microcercous and 2 ubiquità. Ubiquità I and furcocystocercous were the most prevalent species accounting for 66% and 25%, respectively, of total cercaria fauna. Double infections were recorded in only 6 (0.8%) of the infected snails. The overall prevalence of C. bifasciata shedding cercariae was highest (6-10%) in spring and summer, and species diversity was highest (11 species) in fall and spring. Seasonal variations in prevalence and diversity of cercariae were related to environmental factors and hosts behavior.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4047. Seasonal variation in the role of grey squirrels as hosts of Ixodes ricinus, the tick vector of the Lyme disease spirochaete, in a British woodland
- Creator:
- Craine, N.G., Randolph, S.E., and Nuttall, P.A.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Ixodes ricinus, squirrels, mice, voles, pheasants, seasonality, and Borrelia burgdorferi
- Language:
- English
- Description:
- Data are presented on the variable patterns of the seasonal dynamics of Ixodes ricinus L. ticks seen questing on the vegetation and feeding on small rodents (mice and voles) and squirrels within a British woodland focus of Lyme borreliosis. Information on tick infestation levels on pheasants is also presented. The results show a prolonged, unimodal pattern of tick activity, with ticks feeding throughout the year in this sheltered habitat. If host density is taken into account, squirrels are quantitatively more important than small mammals as hosts for larval ticks from April until July, and overwhelmingly so for nymphal ticks throughout the year. The observed inter- and intraspecific differences in tick infestation levels are related to the behaviour of both hosts and ticks. Squirrels, as competent hosts for Borrelia burgdorferi and frequent occupants of habitats closely associated with man, will contribute significantly to the risk of Lyme disease.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4048. Seasonal variations in properties of healthy and diabetic rat heart mitochondria: Mg2+-ATPase activity, content of conjugated dienes and membrane fluidity
- Creator:
- Jana Mujkošová, Miroslav Ferko, Humeník, P., Waczulíková, I., and Atila Ziegelhöffer
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Experimentální medicína, kardiovaskulární fyziologie, mitochondrie, srdce, dieny, cardiovascular physiology, mitochondrias, heart, diens, seasonal variations, mitochondrial Mg2+-ATPase, membrane fluidity, diabetic heart, 14, and 616-092
- Language:
- English
- Description:
- Our previous preliminary results pointed to possible seasonal variations in Mg2+-ATPase activity of rat heart mitochondria (MIT). It is not too surprising since seasonal differences were already reported in myocardial function, metabolism and ultrastructure of the intact as well as hemodynamically overloaded rabbit hearts and also in other tissues. The present study is aimed to elucidate whether seasonal differences observed in rat heart MIT Mg2+-ATPase activity will be accompanied with changes in membrane fluidity and in the content of conjugated dienes (CD) in the lipid bilayers of MIT membranes as well as whether the above seasonal differences will also be present in the diabetic heart. Our results revealed that values of Mg2+-ATPase activity in the winter/spring-period (W/S-P) exceeded significantly (p<0.05-0.001) those in the summer/autumn-period (S/A-P). Similar trend was also observed in hearts of animals with acute (8 days) streptozotocin diabetes. With the exception of values of CD in the S/A-P, all values of Mg2+-ATPase activities, membrane fluidity and CD concentrations in diabetic hearts exceeded those observed in the healthy hearts. Our results indicate that seasonal differences may play a decisive role in the evaluation of properties and function of rat heart MIT., J. Mujkošová, M. Ferko, P. Humeník, I. Waczulíková, A. Ziegelhöffer., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4049. Seasonal variations of gonadotropins and prolactin in the laboratory rat. Role of maternal pineal gland
- Creator:
- Vázquez, N., Díaz, E., Fernández, C., Jiménez, V., Esquifino, A., and Díaz, Beatrice López
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, hormony hypofýzy, laboratorní zvířata, physiology, pituitary hormones, laboratory animals, gonadotropiny, prolaktin, maternal pineal gland, seasonal variations, gonadotropins, prolactin, 14, and 612
- Language:
- English
- Description:
- The laboratory rat, a non-photoperiodic rodent, exhibits seasonal fluctuations of melatonin. Melatonin has been found to be readily transferred from the maternal to the fetal circulation. No data exist on the possible influence of maternal pineal gland upon seasonal variations of the offspring. The aim of the present study was to asses the influence of the maternal melatonin rhythm on the offspring postnatal development of the reproductive hormones LH, FSH and prolactin. Male offspring from control, pinealectomized (PIN-X) and PIN-X + melatonin (PIN-X+MEL) mother Wistar rats were studied at 21, 31, and 60 days of age. Seasonal age-dependent variations were found for all hormones studied in control offspring but PIN-X offspring showed a tendency to have reduced duration or altered seasonal variations. Maternal melatonin treatment to PIN-X mothers partially restored the effect of pinealectomy. The chronological study of LH, FSH, and prolactin in PIN-X offspring also showed an altered pattern as compared to control-offspring. Melatonin treatment to the mothers partially restored the developmental pattern of reproductive hormones. Results of this study indicate that maternal pineal gland of the laboratory rat is involved in the seasonal postnatal development variations of reproductive hormones of the offspring., N. Vásquez, E. Díaz, C. Fernández, V. Jiménez, A. Esquifino, B. Díaz., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4050. Second generation of conical strain gauge probe for stress measurement in rock massif
- Creator:
- Jaromír Knejzlík, Rambouský, Zdeněk, Kamil Souček, and Staš, Lubomír
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, geodynamika, geodynamics, stress measurement, over-coring, 7, and 551
- Language:
- English
- Description:
- Compact conical strain gauge probe for borehole over-coring rock massif stress measurement (CCBO), based on experiences of K. Sugavara and Y. Obara, has been developed in Institute of Geonics ASCR, v.v.i. from 2004. First generation of CCBO is equipped by simple electronic circuit which requires continuous communication with control computer in the course of measurement. Prototypes of this type probes are used for long term stress changes monitoring induced by longwall advancement in mine. Solving of continuous data communication through rotating drilling tool filled by wash water in course of over-coring is very difficult technical task, which is not possible to solve in terms of grant project. To avoid this problem a development of second generation of CCBO equipped by microprocessor and internal data logger was initialised. Simplified modification of CCBO is developed as a probe for long-term monitoring of rock massif stress changes (Compact Conical Ended Borehole Monitoring - CCBM). Design of both models probes, discussion of measurement errors and technique of sensitivity self-calibration is described., Jaromír Knejzlík, Zdeněk Rambouský, Kamil Souček and Lubomír Staš., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public