• Animal Systematics, Evolution and Diversity
• /
• 제27권2호
• /
• pp.115-122
• /
• 2011

The morphology of the two marine hypotrichous ciliates Apokeronopsis bergeri and A. ovalis, isolated from the Yellow Sea, Korea, are described based on live and protargol-impregnated specimens. It is the first time that these species have been recorded in Korea. In addition, the small subunit ribosomal RNA gene was sequenced for comparison with the public database. The genus Apokeronopsis has recently been established in the family Pseudokeronopsidae, and the two congeners of the Korean population share the following characteristics: one row of one or more buccal cirri; usually two frontoterminal cirri; midventral complex composed of two distinctly separated rows; one left and one right marginal row; number of transverse cirri, more than eight; absence of caudal cirri; two types of cortical granules. Apokeronopsis bergeri differs from A. ovalis primarily in body shape (fusiform vs. oval form), size (usually $260{\times}80{\mu}m$ vs. $160{\times}55{\mu}m$), type II cortical granules (oval vs. round shape; yellow-green vs. mostly colourless and only a few yellow-green in colour), and morphometric data (75-106 vs. 53-70 in adoral membranelles; 37-47 vs. 24-36 in frontal cirri; 9-15 vs. 1-2 in buccal cirri), as well as molecular data (2.87% of pairwise distance).

• Ocean and Polar Research
• /
• 제31권1호
• /
• pp.77-95
• /
• 2009

Ciliate abundance and biomass were determined at three anchored stations in the Han River estuary trimonthly from May 2006 to February 2008. The total abundance of ciliates ranged from 0-13,853 cells $l^{-1}$ and biomass ranged from $0.00-73.98\;ugC\;l^{-1}$. Owing to the large seasonal temperature variation (range 0.20-$27.2^{\circ}C$), ciliate abundance displayed marked seasonal variation, being higher in summer than in other seasons. Tintinnids dominated the ciliate communities at station YC where suspended sediment was highest. Difference of ciliate biomass between ebb tide and flood tide were irregular. Seasonal variations of ciliate carbon biomass at each station were related to temperature, suspended sediment and chl.a, especially nano chl.a. Geographical variations of ciliate carbon biomass in each season were related to suspended sediment and salinity.

• Journal of Species Research
• /
• 제1권1호
• /
• pp.78-86
• /
• 2012

Three ciliate species of genus Cyrtohymena, C. australis Foissner, 1995, C. citrina (Berger & Foissner, 1987) and C. muscorum (Kahl, 1932) new to Korea, were collected from semi-terrestrial habitats. The description was based on the observation of live and silver stained specimens. Diagnostic characteristics of these species are as follows. C. autralis: size about $275{\times}100{\mu}m$ in live specimens. Cortical granules yellowish. 18-31 right and 31-40 left marginal cirri in number. Dorsal kineties eight rows. C. citrina: size about $180{\times}50{\mu}m$ in live specimens. Cortical granules yellowish. 26-32 right and 23-27 left marginal cirri in number. Dorsal kineties five to six rows. C. muscorum: size about $180{\times}60{\mu}m$ in live specimens. Cortical granules reddish. 31-34 right and 33-36 left marginal cirri in number. Dorsal kineties six rows. Three species of Cyrtohymena have been added to Korean ciliate fauna from this study. Including previous one species of C. quadrinucleata, four species of this genus in total have been recorded so far in this country.

• Animal Systematics, Evolution and Diversity
• /
• 제31권4호
• /
• pp.277-283
• /
• 2015

Two pleurostomatid ciliates, Loxophyllum perihoplophorum Buddenbrock, 1920 and L. rostratum Cohn, 1866, were collected from the coastal waters of the East Sea, Korea. Their morphologies are described based on live observation and protargol staining, and morphometrics are provided. Loxophyllum perihoplophorum is characterized by the following features: 200-650 μm long in vivo; body slender leaf-shaped, flexible and contractile, with thin and wide extrusome-belted zone; 2 macronuclear nodules (Ma) and 1 micronucleus (Mi); 7-9 contractile vacuoles (CV) positioned along dorsal margin; extrusomes (Ex) evenly distributed along edge of entire body, with about 10 dorsal warts (Wa); 9-11 left (LSK) and 19-22 right somatic kineties (RSK), 4-5 furrows (Fu) on left side. Loxophyllum rostratum is about 100-130 μm long in vivo; body oblate leaf-shaped, contractile, convex ventral side and S-shaped dorsal side, beak-like anterior end; 2 Ma and 1 Mi; 1 CV terminally located; Ex distributed along edge of entire body, with about 9-10 dorsal Wa; 7-8 LSK and 15-19 RSK, ca. 5 Fu on left body side. In addition, sequences of small subunit ribosomal DNA were determined from these two Loxophyllum species and compared with the known Loxophyllum sequences.

• 한국어병학회지
• /
• 제21권3호
• /
• pp.167-174
• /
• 2008

Few studies on parasitic scutica-like ciliates (SLCs) influencing larval growth and survival during the seed production of the Japanese scallop, Patinopecten yessoensis have been performed in spite of relatively high magnitude of their infectious damage to the larvae. In the mass seed production of the scallop, SLCs were never infectious during D-larval stage which lasted 6 to 7 days. Indeed, the infection first occurred in 2 to 4 days after first umbo-staged larvae. A regular selection of active larvae in swimming behavior kept larval SLC infection low throughout the culture compared to unselected control (P<0.05) in which all the larvae alive were contained. Higher infection frequencies of the unselected control resulted in lower larval survivals and wider range of larval size distribution that drove larval attachment rate lower. To the worse, the nursery spats from the higher SLC infection exhibited a retarded growth and elevated occurrence of abnormal scallop.

• Journal of Species Research
• /
• 제9권4호
• /
• pp.427-442
• /
• 2020

We collected indigenous Korean ciliate species from diverse aquatic and terrestrial habitats in 2018 and 2019. The morphology of these ciliates was revealed based on the observations of living cells, and protargol-impregnated and/or silver carbonate-impregnated specimens. During this study, we found 16 previously unrecorded Korean ciliate species, which are as follows: 1) class Heterotrichea - Stentor introversus; 2) class Spirotrichea - Aspidisca orthopogon, Amphisiella sinica, Epiclintes auricularis rarisetus, Apokeronopsis wrighti, Pseudokeronopsis carnea, Trachelostyla pediculiformis, Strombidium apolatum, and Varistrombidium kielum; 3) class Phyllopharyngea - Chlamydodon obliquus, Dysteria aculeata, and Hartmannula angustipilosa; 4) class Litostomatea - Paraspathidium apofuscum; and 5) class Oligohymenophorea - Frontonia angusta solea, Metanophrys sinensis, and Uronemita binucleata. Here, we provide a diagnosis for each species with a brief remark. Among them, the infraciliature of the poorly known species, Stentor introversus and Dysteria aculeata, is described for the first time. Further, we revise the Korean population of Pseudokeronopsis pararubra, which was previously misidentified as Pseudokeronopsis carnea.

• Journal of Species Research
• /
• 제11권4호
• /
• pp.278-286
• /
• 2022

During a field survey of Korean marine ciliates, we collected Pleuronema marinum from a brackish water sample. It is characterized by the presence of a contractile vacuole in mid-body, rather than the subterminal/ terminal contractile vacuole as in other congeners. The cells were examined in vivo and based on protargol and 'wet' silver nitrate impregnation. In addition, the nuclear 18S rRNA gene was sequenced using a single cell. The Korean population morphologically and molecularly resembles a Chinese population of P. marinum. Historical review of the species concludes that 1) two or more species have been assigned into P. marinum, 2) the position of contractile vacuole (e.g., in mid-body) is a valid character state, and 3) P. marinum is probably a rare species. Here we provide a monographic treatment of P. marinum to clarify the issue and for further studies of relevant species. Considering there are about 40 nominal species and complex nomenclatural acts in the genus Pleuronema, further studies should provide descriptions based on protargol and 'wet' silver impregnation with marker gene(s).

• Journal of Species Research
• /
• 제12권3호
• /
• pp.203-211
• /
• 2023

Five ciliate species of Euplotes were isolated from fresh and coastal water during a sampling survey to identify unrecorded ciliates in South Korea. Their morphology was investigated using live observation, protargol and "wet" silver nitrate staining methods. Brief descriptions and microphotographs of each species and a comparison with related species are provided. Euplotes focardii is characterized by an average size of 65×47 ㎛ after protargol impregnation, 6 dorsal and 3 ventral ridges and dorsal argyrome pattern of double-eurystomus type. Euplotes nobilii shows an average size of 34×20 ㎛ after protargol staining, 6 dorsal and 3 ventral ridges and dorsal argyrome pattern of double-patella type. Euplotes octocarinatus, the only freshwater species described in the present study, is characterized by an average size of 66×46 ㎛ after protargol impregnation, 6 dorsal and 3 ventral ridges and dorsal argyrome pattern of double-patella type. Euplotes petzi has an average size of 43×30 ㎛ after protargol staining, a macronucleus hook-shaped and dorsal argyrome pattern in double-patella type. Euplotes raikovi is characterized by an average size of 40×24 ㎛ after protargol staining, 6 dorsal and 3 ventral ridges and dorsal argyrome pattern of double-patella type.

• 환경생물
• /
• 제33권4호
• /
• pp.403-411
• /
• 2015

본 연구는 외부 해수가 계속적으로 유입되는 개방형 인공생태계와 해수의 유입이 없는 폐쇄형 인공생태계에서 미소생태계의 변화를 파악하고자 실험실 내에서 100 L 크기의 인공해양소형생태계 연구를 수행하였다. 수온은 폐쇄형 및 개방형 인공생태계에서 큰 차이가 없었다. 염분은 폐쇄형 생태계에서 수체의 증발에 따라 증가를 보였고 용존산소 및 용존무기질소 농도는 폐쇄형에서 감소하는 반면, 개방형에서는 초기농도와 큰 차이를 보이지 않았다. 용존무기인 및 용존규소는 두 시스템에서 차이가 없었다. 식물플랑크톤은 폐쇄형에서 감소를 하였던 반면, 개방형에서는 증가 양상을 보였으나 Autotrophic nanoflagellates는 식물플랑크톤 개체수의 변동과 반대되는 양상을 보였다. 타가영양세균은 폐쇄형에서 증가하는 양상을 보였고, 이와 함께 heterotrophic nanoflagellates 및 섬모충이 시간차를 두어 증가하는 양상을 보였다. 그러나, 개방형 인공생태계에서는 특이한 변화를 나타내지 않았다. 결론적으로, 폐쇄형 인공생태계와 개방형 인공생태계에서 미소생물상 및 환경요인들의 변화의 연구는 향후 연구자들이 인공생태계 연구에 있어서 기초자료로 활용할 수 있을 것으로 기대하며, 신뢰성 있는 인공생태계 연구를 수행할 수 있을 것으로 판단된다.

• 대한수의학회지
• /
• 제30권1호
• /
• pp.15-27
• /
• 1990

Effects of oral administration of electrolyte solutions were studied in experimentally dehydrated adult sheep. By the latin square method five ruminal fistulated sheep were examined and dehydrated by deprivation of feed and water for 72 hours. Tap water, physiological saline, 0.45% NaCl+120 mM/L glucose and 0.9% NaCl+1% propylene glycol solution were orally administrated after dehydration, respectively. Rehydration effect and modification of the rumen function were compared. 1. After 72 hours of deprivation of feed and water, sheep were hypertonic dehydrated and blood acid-base parameters were not significantly changed. And there was marked increase in ruminal pH and decrease in ruminal total volatile fatty acid(VFA) concentration. 2. After the fluids administration the changes in blood acid-base parameters were not significant in all groups. 3. Although glucose fermentation in the rumen was observed, 0.45% NaCl+120 mM/L glucose was more effective in rehydration than physiological saline and tap water. But it was difficult to know the rehydration effect of 0.9% NaCl+1% propylene glycol solution exactly because of excessive increase in plasma osmolality. 4. After refeeding, total concentration and proportions of ruminal volatile fatty acid(VFA) were not significantly different among groups and recovered to normal concentration but not in proportions after 2 days in all groups. 5. In vitro cultured ruminal protozoa were susceptible to the decrease of the pH and osmolality.