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61.
62.
Giffard-Mena I Charmantier G Grousset E Aujoulat F Castille R 《Development, growth & differentiation》2006,48(3):139-151
The ontogeny of the digestive tract (DT) and of Na(+)/K(+)-ATPase localization was investigated during the early postembryonic development (from yolk sac larva to juvenile) of the euryhaline teleost Dicentrarchus labrax reared at two salinities: seawater and diluted seawater. Histology, electron microscopy and immunocytochemistry were used to determine the presence and differentiation of ion transporting cells. At hatching, the DT is an undifferentiated straight tube over the yolk sac. At the mouth opening (day 5), it comprises six segments: buccopharynx, esophagus, stomach, anterior intestine, posterior intestine and rectum, well differentiated at the juvenile stage (day 72). The enterocytes displayed ultrastructural features similar to those of mitochondria-rich cells known to be involved in active ion transport. At hatching, ion transporting cells lining the intestine and the rectum exhibited a Na(+)/K(+)-ATPase activity which increased mainly after the larva/juvenile (20 mm) metamorphic transition. The immunofluorescence intensity was dependent upon the stage of development of the gut as well as on the histological configuration of the analyzed segment. The appearance and distribution of enteric ionocytes and the implication of the DT in osmoregulation are discussed. 相似文献
63.
Although Uncinaria stenocephala is the most frequent hookworm in the intestine of dogs from Northern, Central and Southern Europe, little is known about its host-parasite relationship. Three groups of sera from dogs (Group 1: dogs naturally infected only by U. stenocephala; Group 2: helminth-free dogs at necropsy, and Group 3: dogs parasitized by other helminths) were analyzed by ELISA using U. stenocephala antigens from adult worms (somatic and excretory-secretory antigens) and from L3 larvae (somatic antigens). All three sources of antigens were found to be suitable for immunodiagnosis of canine uncinariosis with up to 90% efficacy. However, an analysis to assess the diagnostic value of the different antigens demonstrated that the adult excretory-secretory antigens had a higher diagnostic efficacy (96.7%), indicating that this is the best antigen source for the diagnosis of Uncinaria infection. 相似文献
64.
Kato-Yoshinaga Y Nagano M Mori S Clare AS Fusetani N Matsumura K 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2000,125(4):511-516
We previously isolated a larval settlement-inducing protein complex (SIPC) from adult extracts of the barnacle, Balanus amphitrite using a nitrocellulose membrane settlement assay. In the present study, we found that the extracts of other adult barnacles, Megabalanus rosa and Balanus eburneus, also induced the settlement of B. amphitrite cyprids although the inductive activity was slightly lower than that of conspecific extracts. Furthermore, we examined reactivity to anti-SIPC antibody in adult extracts from six species of Japanese barnacles other than B. amphitrite, brine shrimp and eight marine sessile organisms besides barnacles. The results showed that all barnacles examined contained SIPC-like proteins with slightly different molecular weight, while the other animals did not react to the antibody by immunoblot analysis. These findings suggest that species specificity in settlement-inducing proteins of barnacles is not so strict, but these proteins are characteristic to barnacle species. 相似文献
65.
《水生昆虫》2012,34(2):207-222
Bacillus thuringiensis subsp. israelensis (Bti) preparations are widely used for culicid larvae. There is no suitable commercially available analytical method for Cry4 toxin as active ingredient in Bti preparations. To overcome this limitation, an enzyme-linked immunosorbent assay (ELISA) was developed for quantitative determination of Cry4 toxin allowing a limit of detection (LOD) of ~2 ng ml?1 in water. Preconcentration of aqueous samples by lyophilisation resulted in low but reproducible recoveries (25.7±6.8%), and the practical LODs for Bti preparations VECTOBAC WDG granulate and VECTOBAC 12 AS suspension were found to be ~170 ng ml?1 and ~900 ng ml?1, respectively. ELISA determinations indicated a rapid decay in detectable concentrations of VECTOBAC WDG applied at 400 ng ml?1 concentration in surface water: detected concentrations decreased by 18% and 44% in 4 days in water collected from two locations, and dropped below LOD afterwards. Larval mortality of Aedes aegypti indicated a continuous decrease even thereafter. Thus, quantitative Cry4 toxin detection facilitates proper timing and frequency of treatments to achieve optimal efficacy. 相似文献
66.
Park HK Chang SW Kang SW Cho MK Choi SH Hong YC Lee YS Jeong HJ Yu HS 《The Korean journal of parasitology》2008,46(2):59-63
In order to obtain greater insight into the relevant genomic expression patterns of Trichinella spiralis, 992 expressed sequence tags (ESTs) were collected from a cDNA library of T. spiralis muscle stage larvae and assembled into 60 clusters and 385 singletons. Of them, 445 (44.7%) ESTs were annotated to their homologous genes, and small fractions were matched to known genes of nematodes. The annotated ESTs were classified into 25 eukaryotic orthologous groups (KOG). Cytochrome C oxidase (34 clones) was found to be most frequent species. 相似文献
67.
Maemonstrilla gen. nov. , known exclusively from females, is proposed for Monstrilla longipes A. Scott, 1909, M. turgida A. Scott, 1909, and five new species from coral reef plankton in the Ryukyu Islands, Japan: Maemonstrilla hyottoko sp. nov. (type species), M. polka sp. nov. , M. spinicoxa sp. nov. , M. simplex sp. nov. and M. okame sp. nov. A syntype of M. turgida was examined, but the holotype of M. longipes is lost; the latter species, being similar to several of the new species, is regarded as unidentifiable, and the identity of specimens assigned to it by several authors is put in doubt. Until now, all known female monstrilloids have had posteriorly trailing ovigerous spines, but in Maemonstrilla gen. nov. these spines point anteriorly and hold the egg mass between the legs beneath the thorax. This is the first known instance of subthoracic brooding in a planktonic copepod; its functional significance is discussed, and brooding habits of non‐planktonic copepods are briefly reviewed. The intercoxal sclerites of legs 1–4 in Maemonstrilla gen. nov. are very wide, making room for the eggs. In all species except M. turgida comb. nov. , the inner seta of the proximal segment of each leg ramus is either absent or reduced to a nub; this may lessen interference of the egg mass with leg movement. All species have a uniramous leg 5 with two setae, except M. turgida comb. nov. (biramous with setae on both rami); M. turgida comb. nov. is evidently the sister‐group of its congeners, each sister‐group in the genus being defined by additional autapomorphies. Scanning electron micrographs of all the Ryukyuan species except M. simplex sp. nov. are provided; these constitute a preliminary survey of monstrilloid integumental organs and cuticular ornamentation. Among the unusual features are two lobes at the base of the coxa in legs 1–4 of M. polka sp. nov. and M. spinicoxa sp. nov. and two pairs of posterodorsal spine‐like scales on the first and second free pedigers of M. turgida comb. nov. Newly hatched nauplii of M. okame sp. nov. , examined by scanning electron microscopy, are generally similar to those of Monstrilla hamatapex Grygier & Ohtsuka, 1995, but with a different mandibular structure in which the distal hook and seta clearly represent the endopod, not enditic armament of the basis. © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 152 , 459–506. 相似文献
68.
We observed Suwannee River Gulf sturgeon, Acipenser oxyrinchus desotoi, in the laboratory and found free embryos (first interval after hatching) hid under rocks and did not migrate. Thus, wild embryos should be at the spawning area. Larvae (first interval feeding exogenously) initiated a slow downstream migration, and some juveniles (interval with adult features) continued to migrate slowly for at least 5 months, e.g., a 1-step long larva-juvenile migration. No other population of sturgeon yet studied has this migration style. A conceptual model using this result suggests wild year-0 sturgeon have a variable downstream migration style with short-duration (short distance) migrants and long-duration (long distance) migrants. This migration style should widely disperse wild fish. The model is supported by field studies that found year-0 juveniles are widely dispersed in fresh water to river km 10. Thus, laboratory and field data agree that the entire freshwater reach of river downstream of spawning is nursery habitat. Foraging position of larvae and early juveniles was mostly on the bottom, but fish also spent hours holding position in the water column, an unusual feeding location for sturgeons. The holding position of fish above the bottom suggests benthic forage in the river is scarce and fish have evolved drift feeding. The unusual migration and foraging styles may be adaptations to rear in a river at the southern limit of the species range with poor rearing habitat (low abundance of benthic forage and high summer water temperatures). Suwannee River Gulf sturgeon and Hudson River Atlantic sturgeon, A. o. oxyrinchus, are similar for initiation of migration, early habitat preference, and diel migration. The two subspecies differ greatly for migration and foraging styles, which is likely related to major differences in the quality of rearing habitat. The differences between Atlantic sturgeon populations show the need for geographical studies to represent the behavior of an entire species. 相似文献
69.
贡嘎蝠蛾初孵幼虫迁移行为观察 总被引:1,自引:0,他引:1
在实验室内对贡嘎蝠蛾Hepialusgonggaensis的初孵幼虫迁移行为进行了初步观察。结果表明 ,该初孵幼虫迁移与其习性、虫口密度、环境湿度、栖居场所、食料等因素均有关。 相似文献
70.
Bird A.F. and Stynes B.A. 1981. The life cycle of Anguina agrostis: Development in the host plant. Internationaljournal for Parasitology11: 431–440. The growth and development of the infective second stage “dauer” larvae (DL2) of Anguina agrostis into adults have been followed under field conditions in rye grass (Lolium rigidum). Three moults were observed to occur during the parasitic phase of development. From the third (second parasitic) moult onwards, there was much more variability in the size of the female nematodes than in the males and sexual dimorphism became very pronounced. The transition from the DL2 to the second stage parasitic larva (PL2) is marked by the disappearance of the numerous lipid storage granules which are characteristic of the DL2, and the development in the PL2 of an intestine which becomes more pronounced in each succeeding stage, particularly in the adult female. Anguina agrostis is unusual among parasitic nematodes in that the DL2 has the thickest cuticle of all stages, including adults. The L4 and adult males have thicker cuticles than the females at the same stages of development. Moulting appears to involve resorption of the innermost basal zone of the shed cuticle as well as morphological and chemical changes to the epicuticle. 相似文献