• Ocean and Polar Research
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• 제31권3호
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• pp.265-276
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• 2009

Acartia hongi is the most dominant and widespread planktonic copepod in Gyeonggi Bay, Yellow sea. Ingestion rates and selectivity of A. hongi on phytoplankton and planktonic ciliates were determined in the laboratory. Ingestion rates of A. hongi on planktonic ciliates and phytoplankton increased in proportion to prey concentration increase. When A. hongi was fed with various mixture combinations of planktonic ciliates and phytoplankton, their ingestion rate on ciliates tended to increase as the percentage of ciliates in prey biomass increased. Clearance rate of A. hongi on planktonic ciliates was higher than for phytoplankton in all experiments without regard to relative percent of ciliate biomass. This trend suggests that A. hongi was preferentially preying on planktonic ciliates. Under mixed prey availability, it is likely that selective feeding and higher clearance rate of planktonic ciliates by A. hongi is related to the higher nutritional value of ciliates compared to phytoplankton. Therefore, our results suggest that selective ciliate feeding by A. hongi will positively benefit its growth and abundance, and as a result negatively impact the population dynamics of planktonic ciliates in Gyeonggi Bay.

• Animal Bioscience
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• 제37권2_spc호
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• pp.385-395
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• 2024

Ruminal ciliates are a fundamental constituent within the rumen microbiome of ruminant animals. The complex interactions between ruminal ciliates and other microbial guilds within the rumen ecosystems are of paramount importance for facilitating the digestion and fermentation processes of ingested feed components. This review underscores the significance of ruminal ciliates by exploring their impact on key factors, such as methane production, nitrogen utilization efficiency, feed efficiency, and other animal performance measurements. Various methods are employed in the study of ruminal ciliates including culture techniques and molecular approaches. This review highlights the pressing need for further investigations to discern the distinct roles of various ciliate species, particularly relating to methane mitigation and the enhancement of nitrogen utilization efficiency. The promotion of establishing robust reference databases tailored specifically to ruminal ciliates is encouraged, alongside the utilization of genomics and transcriptomics that can highlight their functional contributions to the rumen microbiome. Collectively, the progressive advancement in knowledge concerning ruminal ciliates and their inherent biological significance will be helpful in the pursuit of optimizing rumen functionality and refining animal production outcomes.

• 한국해양학회지:바다
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• 제19권4호
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• pp.265-271
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• 2014

시화호에서 식물플랑크톤 및 섬모충류의 포식자인 중형동물플랑크톤 개체수가 크게 증가하는 하계에 섬모충류의 초식압에 미치는 중형동물플랑크톤의 영향을 파악하기 위해 희석실험과 요각류 첨가 배양 실험을 병행하였다. 희석실험에서 섬모충류는 식물플랑크톤 생산량의 104%를 하루에 소비하였으나, 요각류 Acartia sinjiensis를 첨가한 실험구에서 섬모충류의 초식압은 19%로 크게 감소하였다. 이는 미소형식물플랑크톤의 주요 초식자인 $>20{\mu}m$ 빈섬모충류에 대한 중형동물플랑크톤의 선택적 섭이에 기인하는 것으로, 중형동물플랑크톤에 의해 섬모충류의 개체수가 강하게 지배되는 시기에는 섬모충류의 실제 초식압은 과대평가될 수 있음을 의미한다. 따라서 시화호에서 요각류 개체수가 크게 증가하는 춘계와 하계에는 식물플랑크톤의 초식자로서 섬모충류의 역할은 크게 감소될 것으로 판단되며, 초식자로서 섬모충류의 역할을 더 정확하게 평가하기 위해서는 섬모충류에 대한 중형동물플랑크톤의 포식압을 반드시 고려해야 할 것으로 보인다.

• 대한수의학회지
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• 제35권2호
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• pp.327-336
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• 1995

This study was carried out to develop the animal protein(feed for fry) that was isolated, purified and lyophilized the rumen ciliates from the healthy rumen contents which have $10^5-10^6/g$ ciliates and were discarded in abattoirs. The rumen ciliates are non-pathogenic, anaerobic and the weight of this protozoa is 2% of rumen content. The rumen protozoan and bacterial proteins both have a biological value for rats of 80-81, which is higher than the 72 of brewer's yeasts. Furthermore, the true digestibility and net protein utility of the protozoan protein are 91 and 73, much higher than those of bacterial(74 and 60) or yeast(84 and 60) proteins. The amino acids of rumen protozoa is nutritionally superior than the others. The size of rumen ciliates is $30-200{\times}20-110{\mu}m$ and so we had isolated and purified the rumen ciliates from the rumen contents by the physical methods. The purified rumen protozoa was lyophilized with freezing dryer. The results of this experiment were as follows : 1. Population dynamics of protozoan ciliates in slaughtered rumens; % of samples which small ciliates were predominated was 82.5%(52/63) and that of large ciliates was 17.5%(11/63). 1) predominant species of small ciliates were Entodinium ovinum and E nanellum. 2) predominant species of large ciliates were Epidinium ecaudatum and Diploplastron affine. 2. The lyophilized rumen ciliates which were isolated and purified from 1 kg of rumen content at the pH 6.2-6.8 was about 7.0 gram. 3. The nutrient analysis of lyophilized rqmen ciliates(LRC) was as follows: 1) Proximate analysis of the LRC and the composition of fry feed; moisture 8.05%(below 10.0), protein 35.37%(45), fat 5.39%(4.5), fiber 1.23%(below 2.5), ash 2.25%(below 15.0), Ca 0.26%(below 2.0), P 0.14%(below 1.1), energy 4,608.11(fish meal 5000 cal/g) 2) Amino acids (% in crude protein) of the LRC and the rotifer(Brachionus plicatilis); Arg 5.19%(4.50), His 2.50%(1.55), Ile 5.29%(3.45), Leu 8.11%(5.85), Lys 10.34%(6.15), Met 2.25% (0.85), Phe 5.66%(3.80), Thr 5.14% (3.45), Val 4.18%(3.90), Ala 4.13%(3.35), Asp 13.26%(8.25), Glu 16.62%(9.20), Gly 4.23%(3.10), Pro 3.25%(5.05), Ser 4.85%(3.85), Tyr 5.04%(3.05) 3) Fatty acids(% in fat) of the LRC and the rotifer(biological feed ; Brachionus plicatilis); myristic acid(C14:0) 3.27%(0.3), myristoleic acid(C14:1) 0.83%(-), palmitic acid(C16:0) 39.11% (23.5), palmitoleic acid(C16:1) 2.81%(2.0), stearic acid(C18:0) 9.36%(5.6), oleic acid(C18:1) 25.54%(3.5), linoleic acid(C18:2) 15.05%(32.9), linolenic acid(C18:3) 1.74%(9.8). Judging from the above investigated results, the analytical data of proximate analysis, amino acids, fatty acids of the purified and lyophilized rumen protozoa are reasonable for the feed of freshwater fishes(fry and fingerling). But it was disappointed of our expectation that the crude protein of lyophilized rumen ciliates contains low percentage, it was thought that because of the small ciliates(starch digester) in beef cattle rumens which were administered the concentrated feed, is much difficult to isolate and purify than the large ciliates(fiber digester).

• Journal of the korean society of oceanography
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• 제32권3호
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• pp.145-155
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• 1997

The distribution of microzooplankton and hydrographic variables were measured in the Virginia portion of Chesapeake Bay and its major rivers. Samples were collected at 14 locations at monthly interval from September 1993 through December 1995. Ciliates were numerically dominated (>90%) and copepod nauplii comprised highest proportion of the total microzooplankton biomass (>77%). Copepod nauplii and ciliates were the most abundant at oligohaline water and rotifers at freshwater. Total microzooplankton density and biomass were usually higher at oligohaline stations than fresh water and polyhaline stations. Despite high nutrient concentration and phytoplankton density at eutrophic water, micro- and mesozooplankton biomass were low. Mesozooplankton were relatively abundant at polyhaline stations. The comparison between annual mean biomass of ciliates (12.7 ${\mu$}gC/1) and that of autotrophic picoplankton (13.5 {$\mu$}gC/1) revealed that ciliates were a major consumer of picoplankton production. The secondary production by ciliates was 12.7 ${\mu}$gC/1/day, representing 5% of the annual mean primary production in Chesapeake Bay, Total microzooplankton comprised 84% of the total zooplankton carbon content, representing five times higher than mesozooplankton biomass.

• Animal cells and systems
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• 제2권2호
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• pp.165-176
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• 1998

Seasonal changes in microzooplankton abundance were identified in the mesohaline Chesapeake Bay and several tributaries from July 1992 through December 1995. Ciliates numerically dominated, comprising over 90% of the total microzooplankton density and aloricate ciliates usually outnumbered loricate ciliates. Copepod nauplii accounted for the highest microzooplankton biomass (>75% in dry weight). Rotifers made small contributions to the total microzooplankton density and biomass (<5%). Time series analysis indicated a twelve month cycle in microzooplankton abundance, and mid-summer(August) peaks for copepod nauplii, and a spring through fall peaks (May-October) for ciliates. Rotifers showed two seasonal peaks: one in mid-summer(August) at the river stations and the other in mid-winter(February) at the mesohaline stations. Seasonal peaks of copepod nauplii and rotifers coincided with the mesozooplankton abundance peak. On the other hand, ciliate maximum usually occurred between the phytoplankton and mesozooplankton peaks. This pattern of microzooplankton seasonality suggests the intermediate trophic role of microzooplankton (especially ciliates) between the phytoplankton(especially picophytoplankton) and mesozooplankton in Chesapeake Bay and its tributaries.

• 대한수의학회지
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• 제15권2호
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• pp.287-291
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• 1975

In order to observe the kinetic of ciliates inhabited in the stomach, investigation of the content juice in the stomach was carried out on the 30 Korean native cattle, selected as healthy ones and slaughtered at Jeonju abattoir in August, 1974. The following is a brief summary of the leading facts gained through the experiment. 1. The average pH of the content juice showed $6.567{\pm}0.056$(SE) in the rumen, $6.607{\pm}0.053$ in the reticulum, $6.183{\pm}0.056$ in the omasum and $2.627{\pm}0.061$ in the abomasum. 2. The presumed number of ciliates per ml was calculated $168,200{\pm}17,035$(SE) in the rumen, $173,200{\pm}19,728$ in the reticulum, $23.600{\pm}3.537$ in the omasum and $467{\pm}266$ in the abomasum. 3. In the content juice the number of ciliates was gradually slowed down, the pH decreased from rumen to abomasum and the changes were denoted by quadratic curves(parabolas). 4. In accordance with the increase of the number of ciliates the pall also becomes higher and in this situation the correlation coefficient was ${\gamma}_{xy}=0.508$. 5. Population density of ciliates was checked and Entodinium showed 60 per cent among them, but Polyplastron was figured only from 0 to 0.05 per cent. 6. Among 26 species of ciliates which were identified from the content juice, Entodinium simplex was showed the highest population density, raging from 40 to 50 per cent, Dasytricha ruminantium was neat to it, Eudiplodinium affine after the next, and Entodinium caudatum and Eudiplodinium maggi were also found abundantly in the abomasum.

• 한국수산과학회지
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• 제35권5호
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• pp.542-544
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• 2002

This study was carried out to evaluate the ciliates Euplotes sp. as a live food for marine fish larvae. The ciliates and the rotifers Brachionus plicatilis, which were cultured with the baker's yeast Saccharomyces cerevisiae and the $\omega$-yeast emulsified with cuttle fish liver oil, were supplied to the larvae of flounder Paralichthys olivaceus and grouper Epinephelus akaara. Considering the size difference between the ciliates 68 $\cdot$ 7 $\mu$n and the rotifers 160 $\cdot$ 20 $\mu$n, the rotifers and ciliates were supplied to the larvae tank with the density of 2 inds./mL and 20 inds./mL, respectively. The survival rate and growth in length of the flounder larvae fed on rotifer were significantly higher than those on Euplotes sp.. In grouper larvae which have a small mouth diameter, even the survival rate of the larvae fed on the ciliates was better than that on the rotifers, it was very low less than $20\%$. Therefore, Euplotes sp. seem to be incongruent as a live food for marine fish larvae.

• 환경생물
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• 제33권2호
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• pp.189-196
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• 2015

We verified three ciliates - Dysteria brasiliensis Faria et al., 1922, Dysteria lanceolata ${Clapar\grave{e}ede}$ and Lachmann, 1859, and Dysteria ovalis (Gourret and Roeser, 1886) Kahl, 1931 - as previously unrecorded species in Korea. These three ciliates were collected from Incheon Harbor and Geojin Harbor in Korea. We describe the three species based on live observations, protargolimpregnated specimens, and silver nitrate-impregnated specimens.

• 환경생물
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• 제33권2호
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• pp.215-222
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• 2015

During our investigation of ciliates from Korea, four ciliates were isolated from the non-flood Petri dish culture of soil. They were cultured under laboratory condition and studied using standard methods morphologically, including living observations, protargol impregnations, and morphometrics. The four species are Metopus hasei Sondheim, 1929, Urosomoida agiliformis Foissner, 1982, Oxytricha proximata Shibuya, 1930, and Cladotricha sp. in Nie${\ss}$en (1984) respectively.