An examination of a sample of European eels, Anguilla anguilla (L.), collected from Lake Bracciano near Rome in 1993, the only known European locality with the occurrence of the introduced swimbladder nematode Anguillicola novaezelandiae Moravec et Taraschewski, 1988, revealed for the first time the presence of two Anguillicola species, A. novaezelandiae and A. crassus. In view of the investigations carried out by current authors in Bracciano Lake in the years 1982-1992, it is apparent that the latter species has been introduced into the lake quite recently, where it quickly became a dominant species. The development of A. novaezelandiae was experimentally studied in the copepod intermediate host, Cyclops strenuus, for the first time. The copepods were infected with nematode second-stage larvae at 21-22°C; fully developed infective third-stage larvae were obtained 13 days p.i. The general morphology of individual larval stages of A. novaezelandiae was similar to that of larvae of the related species Λ. crassus.
Warmer temperatures in the past 30 years have significantly influenced the seasonal development of insects throughout Europe. As a result of the outbreaks of black flies that have occurred in southeastern Lithuania since the 1970s it is hypothesized that this increase in black fly activity is due to the change in climate. To test this hypothesis the development of Simulium maculatum Meigen under different conditions was determined. This revealed that the time of hatching of S. maculatum eggs in Lithuania was influenced by winter air temperatures, especially those in March. Pupation in S. maculatum is associated with the increase in air and water temperatures that occur at the end of April and in May. The emergence of S. maculatum black flies occurs most often in May. At a water temperature of 13.2°C (1999), S. maculatum took 42 days to develop and half this time (21 days) when the water temperature was 18.8°C (2005). The number of black flies that emerged each year was determined by air temperature but unaffected by rainfall in June (either per month or per ten-day period). and Rasa Bernotienė, Galina Bartkevičienė.
Hyssopus pallidus (Askew) (Hymenoptera: Eulophidae) is a gregarious ectoparasitoid of late larvae of the codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae). In the present work reproduction and the development and morphology of the immature stages were studied. Five larval instars were differentiated by the shape and size of the mandibles. The larvae are hymenopteriform with a weakly sclerotized head and 13 segments. The first instar has four pairs of spiracles, while the other four instars have nine pairs. Under laboratory conditions of 22-24°C and 60-80% RH the egg stage lasted 1.5 days, the larval instars 6.3 days, and the pupal stage 7.9 days in females and 7.2 days in males. The duration of each of the five larval instars (L1-L5) is approximately 1, 0.5, 0.75, 0.75 and 3.5 days, respectively. Male and female development time does not differ significantly in the egg and larval stages, but differences are highly significant in the pupal stage. Male and female pupae can be differentiated by their sexual rudiments. Copulation takes place immediately upon emergence of the females between siblings, adult males appearing before the females. Females in culture with access to an energy source can survive for more than 60 days. They are synovigenic: they emerge with no mature eggs in their ovaries and take the first two days after emergence to mature the full set of around 24-30 eggs. They continue paralyzing hosts, ovipositing and maturing eggs for as long as they live. After an oviposition a female needs two to three days to mature a new full set of eggs. Age and feeding influence egg load. Oösorption is significant in starved females, but also occurs in older fed females with no host contact.
The paper is describing the current state of intermediation services in CZ NUTZ 2 Region Prague, based on results of ongoing SUPER-SME Project of FP6. It is possible to identify an important role of itnermediaries in research, development, and innovation activities. The intermediation aims at otpimizing supply of scientific and technological services, with demad of RTDI companies and organizations or any other actors using or interested in using these services, e.g. national or regional stakeholders. S&T intermediary is defined as a public, private, or public/private (non-profit) instition with a mission of optimizing interface between supply of sicentific and technological services and demand of an enterpirse, groups of enterpirses, or any institution in this respect. Universities, research centrers, private companies, or technology transfer centers can play a role of S&T intermediary., Adolf Filáček., and Obsahuje seznam literatury
The human infection known under the names cercarial dermatitis or swimmers' itch is generally associated with swimming in lakes all over the world, however, a number of outbreaks of cercarial dermatitis developing in salt or brackish waters are also reported. The disease presents as allergic reaction which is able to trap and eliminate the parasites in the skin. However, the infection can be linked to more than skin symptoms under certain circumstances. Recent studies on bird schistosomes have shown that during primary infections of noncompatible hosts (mice) the parasites may migrate through visceral and nervous tissues of mammals. Up to date, cercarial dermatitis has been mostly associated with the cercariae of bird schistosomes of the genus Trichobilharzia. Recent findings of new genera and species indicate, however, broader spectrum of causative agents of the disease with different life cycles, host specificity and pathogenicity.
Three species of planktonie crustaceans, Cyclops strenuus and Macrocyclops alhidus (Copcpoda) and Notodromas monacha (Ostracoda), were experimentally infected with the eggs and second-stage larvae of the swimbladder nematode Anguillicola crassus originating from eels from Neusiedler Lake in Austria. At 20-22°C, third-stage larvae of the parasite developed in all these invertebrate hosts within 16-20 days p.i. Ostracods harbouring the nematode third-stage larvae (33 days p.i.) were fed to small eels (Anguilla anguilla), while infected copepods (20 days p.i.) to seven other fish species. By these experiments, the larvae from ostracods proved to be infective for the definitive host and the ostracod was thus confirmed as a true intermediate host of Anguillicola crassus. Notodromas monacha represents a new experimental intermediate host of A. crassus and the second known invertebrate other than a copepod in which the larval development of this nematode up to the infective stage takes place. Five species of fish, cyprinids Tinca tinea, Alhumus alburnus, Gobio gobio and Albumoides bipunctatus (the latter representing a new host record), and guppy, Poecilia reticulata, were found to serve as experimental paratenic hosts for A. crassus, in which the live nematode infective larvae were recorded 49 days p.i.
Life-history theory predicts trade-offs between resources invested in reproduction and other fitness-related traits. To date, most studies have focused on potential reproductive trade-offs in females. However, it is now generally accepted that reproduction is also costly for males, and thus males too may be subject to trade-offs. We examined the relationship between development time and the production of both fertile and non-fertile sperm in males of the African bush brown butterfly (Bicyclus anynana) selected for short or long pre-adult development time. Fast developing males ejaculated fewer non-fertile sperm on their first mating, suggesting that there could be a trade-off between ejaculate production and development time in this species. Contrary to predictions, slow developing males were smaller, produced fewer fertile sperm and took longer to mate. We discuss why this might be the case, and suggest that there may be a cost to the production of non-fertile sperm in the Lepidoptera.
The development of the nematode Anguillicola crassus, a swimbladder parasite of eels, was experimentally studied in copepod intermediate hosts Cyclops strenuus and Acanthocyclops vernalis. The copepods, kept at a laboratory temperature of 20-22 °C, were infected with nematode second-stage larvae; the second moult of larvae (the only one in the intermediate host) was observed to start 10 days p,i„ but third-stage larvae liberated from their cuticular sheath were first observed 20 days p.i. These proved to be infective for experimental eels. Free second-stage larvae as well as larvae from copepods were described. The morphology of A. crassus larvae and the mode of their development in the intermediate host were compared with those of other dracunculoid nematodes. From this point of view, Anguillicola members appear to represent an ancient group of dracunculoid nematodes.
A description is given of the life cycle of the nematode Procamallanus (Spirocamallanus) rebecae (Andrade-Salas, Pineda-Lopez et García-Magafia, 1994), an intestinal parasite of cichlids in Mexico. The copepod Mesocyclnps sp. was found to be a suitable experimental intermediate host. After the copepod’s ingestion of free first-stage larvae of the nematode, these enter the haemocoel of the intermediate host; they moult twice (on the 3rd and 5-6th day p.i. at 21-22”C) before they attain the third, infective stage. The third-stage larva already possesses the large buccal capsule without spiral thickenings and its tail tip bears three cuticular spines. The larvae undergo two additional moults (13-14 days and 42 days p.i.) in the definitive host (Cichlasoma urophthalmus) before changing to adults; the prepatent period is about 2-3 months. Experimental infection of guppies, Poecilia reticulata, have shown that these fishes may become paratenic (metaparatenic) hosts of this parasite. The morphology of individual larval stages of this nematode is described.
To estimate the significance of insulin in the regulation of preimplantation embryo growth, female mice received a single subdiabetogenic dose of streptozocin (65 mg/kg intraperitoneally) 8-11 days or 14-17 days before fertilization. Mean glycaemia levels and the number of embryos per mouse did not differ significantly between the streptozocin-treated and control groups. Morphological analysis of preimplantation embryos collected on day 3 of pregnancy revealed significant changes in the distribution pattern of preimplantation embryo stages recovered from streptozocin-treated females. Continuous insulin treatment of streptozocin-treated mice improved the impaired development of preimplantation embryos only in short-lasting experiments. After a long subdiabetic period (14-17 days) the incidence of degenerated embryos was increased in both streptozocin-treated groups. It can be concluded that the subdiabetic state in female mice impairs preimplantation embryo development which could partly be prevented by insulin treatment.