• Title, Summary, Keyword: teleost

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The histological structure and the pathologic lesions of teleost skin (어류피부의 조직학적 구조와 병변)

  • Huh, Min-Do
    • Journal of fish pathology
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    • v.5 no.2
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    • pp.159-164
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    • 1992
  • The skin of fishes is also the important external barrier against a variety of the environmental detrimental agents, allowing normal internal physiological function, so its condition is very important in many disease processes. Since fishes are aquatic, morphologically and physiologically they posses specific characteristics lacking in terrestial animals. Thus, it is necessary to keep in mind various specific histologic characteristics for a precise interpretation of the histopathological lesions. In the normal environment the fish skin is more subtly adapted for its physiological requirements as a limiting barrier than the skin of higher terrestial vertebrates. However, its delicacy makes it high vulnerable to damage in fish culture facilities or polluted waters. Although changes in the skin of fish such as discoloration, ulcerative lesions, are the the most readily observed clinical features of fish, there is a wide variety of possible responses, which are best considered in terms of their site within the skin. Up to now, there are relatively few sytematically described information on the histological structure of the teleost skin as well as integrated reviews of the range of pathological processes that can occur in teleost skin. Therefore it was tried in this article to rearrange the information already described by other investigators on the histological structure and histopathological changes of teleost skin.

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The Oogenesis of Glow-light Tetra, Characidae, Teleost (경골어류 카라신과 glow-light tetra의 난자형성과정)

  • Lee, Kyu-Jae;Chang, Byung-Soo;Teng, Yung-Chien;Kim, Dong-Heui
    • Applied Microscopy
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    • v.38 no.4
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    • pp.315-319
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    • 2008
  • Glow-light tetra, Hemigrammus erythrozonus is a teleost belonging to Characidae. The natural habitate of this fish is the wild in the Essequibo river, Guyana and South America. The oogenesis of glow-light tetra was investigated by light microscopy to compare with those of other families. A pair of ovary was located between swim bladder and intestines. The ovary was of white color and ellipsoidal shape with the major axis 11 mm and the minor axis 4 mm. Cytoplasm of oogonia was basophilic and many nucleoli were located at inside of nuclear membrane. In primary oocytes, yolk vesicles were distributed only in the marginal area and egg envelope was not formed on the outside of an egg. In secondary oocytes, the egg envelope was formed and yolk vesicles in the cytoplasm were increased than the earlier stage. The amount of basophilic substance was decreased. In case of matured egg, thickness of egg envelope and size of egg were increased, basophilic substance was distributed in only around the egg envelope. The yolk vesicles were changed to yolk mass in accordance with development. In conclusion, the oogenesis of glow-light tetra, Hemigrammus erythrozonus was characterized by the increase in cell size, the formation and accumulation of yolk, and the decrease of basophilia a in the cytoplasm. The oogenesis of glow-light tetra seems to share common patterns in Characidae, teleost and have a similar pattern with other teleost.

Evolutionary History of Two Paralogous Glyceraldehyde 3-Phosphate Dehydrogenase Genes in Teleosts

  • Kim, Keun-Yong;Nam, Yoon-Kwon
    • Fisheries and aquatic sciences
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    • v.11 no.3
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    • pp.177-181
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    • 2008
  • Glyceraldehyde 3-phosphate dehydrogenase(GAPDH) is a key enzyme for carbohydrate metabolism in most living organisms. Recent reports and our own searches of teleost species in publicly available genomic databases have identified at least two distinct GAPDH genes in a given species. The two GAPDH genes are located on the same chromosome in teleosts, whereas they are located on the different chromosomes in mammals. Thus, we reconstructed a phylogenetic tree to better understand the evolutionary history of the GAPDH genes in the vertebrate lineage. Our phylogenetic analysis revealed unambiguously that the two GAPDH genes of teleosts are phylogenetically closely affiliated to one of the cytosolic GAPDH and spermatogenic GAPDH-S of mammals. This indicates that the two paralogous GAPDH genes shared a common ancestor and subsequently underwent a gene duplication event during early vertebrate evolution. However, GAPDH-S of teleosts showed significant differences in the polypeptide residues and tissue distribution of its mRNA transcripts from that of mammals, implying they have undergone a different history of functionalization.

Feeding Habits of Brown barracuda (Sphyraena pinguis, Teleostei) in the Coastal Waters of Gadeok-do, Korea (가덕도 주변 해역 꼬치고기 (Sphyraena pinguis)의 식성)

  • BAECK Gun Wook;HUH Sung-Hoi
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.37 no.6
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    • pp.505-510
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    • 2004
  • The feeding habits of brown barracuda (Sphyraena pinguis) were analyzed using the stomach contents of monthly samples collected from coastal waters of Gadeok-do, Korea from January to December, 1998. Brown barracuda occurred mainly from summer to autumn in the study area, and ranged from 15 to 35 cm in standard length. Brown barracuda was a piscivorous fish which, mainly consumed teleost fish such as anchovy (Engranlis japonicus) and chefoo thryssa (Thfssa kammalensis). Its diet also included small quantities of shrimp and cephalopods. Although smaller fishes (<25 cm SL) consumed shrimp and cephalopods as well as fish, larger fishes (>30 cm SL) consumed exclusively teleost fish. The prey size increased with increase of fish size.

Changes of the Osmolarity in Embryonic Body Fluid and the Maternal Ovarian Tissue of the Viviparous Teleost, Ditrema temmincki, during the Gestation Period (태생 경골어류, 망상어(Ditrema temmincki)의 임신기 동안 체내자어의 체액삼투압 및 모체 난소조직상의 변화)

  • LEE Jung Sick;CHIN Pyung
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.29 no.2
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    • pp.157-164
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    • 1996
  • Dry weight and body fluid osmolarity of embryo, and maternal ovarian fluid and the ovarian inner tissue of the viviparous teleost, Ditrema temmincki, changed considerably during the gestation period. After the complete absorption of the egg yolk, average dry weight of the embryo increased to 373.76 mg, and the range of total length (TL) was from 6.0 to 60.0 mm. Osmolarity of the embryonic body fluid was 796,8 mOsmol/kg with TL 64.0 mm right before parturition. Ovarian outer membrane started to swelling clearly after fertilization, and maximized in March. The swelling of ovigerous folds was maximized in late April. Expansion of blood vessels and increase of hemocytes reached to their maximum right before parturition. The results of this study indicated that these changes are related to the nutritional and environmental adaptation of both the embryo and the maternal body during the gestation period.

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Cloning and Characterization of Muscarinic Receptor Genes from the Nile Tilapia (Oreochromis niloticus)

  • Seo, Jung Soo;Kim, Moo-Sang;Park, Eun Mi;Ahn, Sang Jung;Kim, Na Young;Jung, Sung Hee;Kim, Jin Woo;Lee, Hyung Ho;Chung, Joon Ki
    • Molecules and Cells
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    • v.27 no.3
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    • pp.383-390
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    • 2009
  • To investigate the regulatory mechanism underlying the contractile response in the intestinal smooth muscle of the nile tilapia (Orechromis niloticus), we used pharmacologic and molecular approaches to identify the muscarinic subreceptors and the intracellular signaling pathways involved in this motility. Myography assays revealed that an M1- and M3-subtype selective antagonist, but not a M2-subtype selective antagonist, inhibited carbachol HCl (CCH)-induced intestinal smooth muscle contraction. In addition, a phospholipase C inhibitor, but not an adenylate cyclase inhibitor, blocked the contractile response to CCH. We also cloned five muscarinic genes (OnM2A, OnM2B, OnM3, OnM5A, and OnM5B) from the nile tilapia. In the phylogenetic analysis and sequence comparison to compare our putative gene products (OnMs) with the sequences obtained from the near complete teleost genomes, we unexpectedly found that the teleost fish have respectively two paralogous genes corresponding to each muscarinic subreceptor, and other teleost fish, except zebrafish, do not possess muscarinic subreceptor M1. In addition, the expression pattern of the nile tilapia muscarinic subreceptor transcripts during CCH-induced intestinal smooth muscle contraction in the proximal intestinal tissue was analyzed by real-time PCR surveys and it was demonstrated that CCH increased the OnMs mRNA expression rapidly and transiently.