• Ocean and Polar Research
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• v.31 no.3
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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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• v.37 no.2_spc
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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.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.19 no.4
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• pp.265-271
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• 2014

We performed dilution experiments together with copepod added incubations to examine the influence of mesozooplankton on the grazing pressure of planktonic ciliates in Sihwa lake during summer when the abundances of phytoplankton and mesozooplankton increased considerably. Planktonic ciliates consumed 104% of primary production in a day on dilution experiments. However, the ciliates consumption on phytoplankton was reduced to 19% in copepod incubations with Acartia sinjiensis added. This was due to selective predation of A. sinjiensis on oligotrich ciliates ($>20{\mu}m$) which were major grazers on nano-phytoplankton. Our experiments show that grazing pressure of planktonic ciliates based on dilution experiments may be overestimated when the abundance of planktonic ciliates is strongly controlled by copepods. We postulate that the role of planktonic ciliates as grazers could diminish in Sihwa lake in spring and summer when abundance of copepods increase considerably. We suggest that the predation of mesozooplankton should be considered to better appraise the role of planktonic ciliates as grazers.

• Korean Journal of Veterinary Research
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• v.35 no.2
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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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• v.32 no.3
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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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• v.2 no.2
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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.

• Korean Journal of Veterinary Research
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• v.15 no.2
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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.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.5
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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.

• Korean Journal of Environmental Biology
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• v.33 no.2
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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.

• Korean Journal of Environmental Biology
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• v.33 no.2
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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.