• Asian-Australasian Journal of Animal Sciences
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• v.4 no.1
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• pp.25-29
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• 1991

Performance and production of twenty lactating Holstein cows fed diets containing either soybean meal or fish meal as the primary protein source were compared in a continuous or split feeding scheme. At 1 wk prepartum four groups of five animals were placed on each experimental diet. Animals assigned to the continuous feeding scheme were continued on these diets for 10-wk postpartum. At 4 wk postpartum, the diets for the groups assigned to switching protein sources were changed. These treatments were continued for another 6 wk. Milk production and dietary intakes were recorded daily. Milk constituents were measured every 2 d. Cows weights, rumen fluid samples and jugular blood samples were collected weekly. Data showed no effect of early lactation diet on cow performance or milk characteristics. Overall, compared to the soybean meal diet, the fish meal diet lowered the milk fat percent and increased production of milk per unit of dry matter ingested. No differences were observed for volatile fatty acid content of rumen fluid, blood mineral content, milk protein, somatic cell count, 4%-fat corrected milk, dry matter intake, or body weight.

• Environmental Engineering Research
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• v.16 no.2
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• pp.103-109
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• 2011

This work experimentally determined the effect of thermal and microwave pretreatments on the anaerobic digestion of mixtures of municipal primary and secondary sludges in semi-continuous mesophilic digesters at hydraulic retention times (HRT) of 20, 15, 10, 7, and 5 days. The ratio of soluble chemical oxygen demand (COD) to total COD in thermally pretreated and microwaved sludges at $80^{\circ}C$ was 2.7 and 3.2 times higher than that of raw sludge, respectively. The volatile solids (VS) and COD removal efficiencies in all three digesters fed with raw (control), thermally pretreated (TM), and microwaved (MW) sludges decreased as the HRT was reduced. The highest relative improvement in VS removal compared to the control occurred at the HRT of 5 days in the TM and MW (29 and 41% higher than the control, respectively). At this HRT, improvement in the COD removal efficiencies in the TM and MW compared to the control was 28 and 53%, respectively. Improvements in biogas production compared with the control increased in both the TM and MW as the HRT was reduced to 5 days. The relative improvement in daily biogas production compared to the control from the TM and MW was 33 and 53% higher than the control at the HRT of 5 days, respectively. The results show that microwave pretreatment is more effective than thermal pretreatment in increasing the solubilization degree and mesophilic anaerobic biodegradability of sewage sludge.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.5
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• pp.629-634
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• 2012

This study was conducted to improve the yield of mature oocytes from in vitro-culture of ovarian primary follicles by optimizing follicle retrieval from neonatal mice of different ages. Primary follicles of 75 to $99{\mu}m$ in diameter were collected daily from 7- to 14-day-old neonatal mice, and subsequently cultured in ${\alpha}$-MEM medium. Number of primary follicles isolated, growth of the follicle during in vitro-culture and maturation of intrafollicular oocytes were monitored. Overall, mean number of preantral follicles per animal was improved from 10.7 to 88.7 as the age of follicle donors was increased from 7 to 14-day-old. Number of primary follicles was increased gradually up to 11-day-old (35.7 follicle per an animal), then reduced to 29 in 14-day-old (p = 0.0013). More follicles retrieved from 10-day-old or 11-day-old females maintained their morphological normality at the end of primary culture than the follicles retrieved from 9-day-old. Of those cultured, primary follicles retrieved from 11-day-old mice yielded largest larger number of early secondary follicles than the follicles retrieved from in the other ages (39 vs. 13 to 29%). More than 3.3-times increase (0.86 to 2.86; p<0.05) in an average number of mature oocytes per animal was observed in the group of 11-day-old, compared with 9-day-old. However, no difference was found in the percentage of primary follicles developing into the pseudoantral stage (21 to 30%; p = 0.5222) and in the percentage of oocytes mucified (32 to 39%; p = 0.5792). In conclusion, a positive correlation between retrieval time and follicle growth was detected, which influences the efficiency to derive mature oocytes by follicle culture.

• Journal of Aquaculture
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• v.20 no.3
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• pp.194-198
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• 2007

Reproductive traits of Palaemon gravieri such as embryo size, number of embryo (fecundity), incubation period, larval development mode, larval development period, larval survival and larval growth were described and compared to analyze the correlation among those traits. Embryo volume is a primary factor determining other ensuing reproductive features. Egg volume was $0.042mm^3$ in the first developmental stage. Embryo volume in P. gravieri was comparatively small which is indicative of great number of embryo (y = 3.0161x + 0.0185 $R^2$ = 0.74 positive isometric relationship) and relatively long incubation period. Larvae survived from zoea 1 to post-larvae and it took 45 days at $22^{\circ}C$. Survival rate of the larvae was rather great in the early stage and thereafter steadily decreased. Daily growth rate of larvae in P. gravieri at $22^{\circ}C$ was 0.0195 mm on average. They grew steadily as time went by. Incubation period was between 10-14 days at $22^{\circ}C$. Larval development mode was almost complete planktotrophic. PNR (point of no return) appeared to be the third day on average. Survival rate of larvae without feeding declined rapidly between 3 and 4 days. Larval development period and stage frequency were 23-30 days and 11 stages which imply prolonged larval period and high mortality. The pattern of brood production followed fast successive parturial pattern. Most ovigerous female had mature ovary when they performed parturial molt soon after hatching (larval release).

• Animal Bioscience
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• v.34 no.9
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• pp.1544-1551
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• 2021

Objective: The purpose of this study was to investigate growth performance, carcass traits, meat quality and hair follicle development of growing Rex rabbits as affected by different environmental enrichment materials. Methods: A total of one hundred and twenty Rex rabbits were randomly assigned to four groups; reared in conventional cages (not enriched) and in enriched cages with either willow stick (WS), rubber duck, or a can containing beans (CB), for 44 days. Results: The average daily gain of the CB group was the highest and had a significant difference from that of the other groups (p<0.05). The spleen and cecum weight of the CB group was greater than those of the WS and control groups (p<0.05). The redness (Commission Internationale de l'Eclairage a^*) of the meat sample of the control group was lower than those of the enriched cage groups (p<0.05). Moreover, the hue value of the CB group was significantly lower than that of the other groups (p<0.05). The tenderest meat belonged to the CB group. In addition, more secondary (p<0.05) and primary follicles were found in the CB group than in the control group. Conclusion: Environmental enrichment increased the average daily gain and improved some carcass traits, meat quality, and hair follicle density. Among the three environmental enrichment materials, CB could be recommended for rabbit husbandry.

• 한국해양학회지
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• v.21 no.1
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• pp.13-24
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• 1986

The daily net primary production by phytoplankton in the southeastern sea of Korea in October 1985 ranged from 0.7 to 2.7 gCm$\^$-2/ d$\^$-1/ and averaged to be 1.3 gCm$\^$-2/ d$\^$-1/. Surface total chlorophyll ranged from 0.97 to 3.59mg chlm$\^$-3/. Primary production by nano-phytoplankton(〈20$\mu\textrm{m}$) ranged from 43 to 97% in the surface layer. Optimum light intensity(Iopt)was around 300 to 700${\mu}$Es$\^$-1/m$\^$-1/. Surface primary production from 9:00 to 15:00 h was evidently inhibited by strong light intensity beyond the Iopt. Phytoplankton near the base of euphotic zone(30-40m) showed extremely low Iopt suggesting adaptation to a low light environment. Since Iopt represents the history of light experience of phytoplankton at a given depth, the extent of variation in I of phytoplankton at different depth seems to be related to the in tensity of turbulence mixing in the surface mixed layer. From the present study, ammonium excretion by macrozooplankton (〉350$\mu\textrm{m}$) contributes from 3 to 19% of daily total nitrogen requirement by phytoplandton in this area. Calculation of upward flux of nitrate to the surface mixed layer from the lower layer, based on the simple diffusion model, approximates 3% of nitrogen requirement by phytoplankton. However, large portion of nitrogen requirement by phytoplankton remains unexplained in this area. In upwelling area near the coast, adjective flux might be the major source for the nitrogen requirement by phytoplankton. This study suggests that the major nitrogen source for the phytoplankton growth might come from the pelagic regeneration by nano-and micro-sized heterotrophic plandkon. Enhancement of primary production during the passage of the warm Tsushima Current is discussed in relation with nutrient dynamics and hydrlgraphic processes in this area.

• ALGAE
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• v.30 no.2
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• pp.121-137
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• 2015

Studies on carbon flux in the oceans have been highlighted in recent years due to increasing awareness about climate change, but the coastal ecosystem remains one of the unexplored fields in this regard. In this study, the dynamics of carbon flux in a vegetative coastal ecosystem were examined by an evaluation of net and gross ecosystem production (NEP and GEP) and $CO_2$ exchange rates (net ecosystem exchange, NEE). To estimate NEP and GEP, community production and respiration were measured along different habitat types (eelgrass and macroalgal beds, shallow and deep sedimentary, and deep rocky shore) at Gwangyang Bay, Korea from 20 June to 20 July 2007. Vegetative areas showed significantly higher ecosystem production than the other habitat types. Specifically, eelgrass beds had the highest daily GEP ($6.97{\pm}0.02g\;C\;m^{-2}\;d^{-1}$), with a large amount of biomass and high productivity of eelgrass, whereas the outer macroalgal vegetation had the lowest GEP ($0.97{\pm}0.04g\;C\;m^{-2}\;d^{-1}$). In addition, macroalgal vegetation showed the highest daily NEP ($3.31{\pm}0.45g\;C\;m^{-2}\;d^{-1}$) due to its highest P : R ratio (2.33). Furthermore, the eelgrass beds acted as a $CO_2$ sink through the air-seawater interface according to NEE data, with a carbon sink rate of $0.63mg\;C\;m^{-2}\;d^{-1}$. Overall, ecosystem production was found to be extremely high in the vegetated systems (eelgrass and macroalgal beds), which occupy a relatively small area compared to the unvegetated systems according to our conceptual diagram of a carbon-flux box model. These results indicate that the vegetative ecosystems showed significantly high capturing efficiency of inorganic carbon through coastal primary production.

• Asian-Australasian Journal of Animal Sciences
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• v.3 no.2
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• pp.103-106
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• 1990

A balance study was conducted to determine the requirements of iron, copper, cobalt and manganese in crossbred calves. Six calves were fed milk average 10 percent of their body weight and were supplemented with 15 g mineral mixture daily. A balance trial was conducted at $2\frac{1}{2}$ months of age. The primary route of excretion was through digestive tract as 99.87, 80.99, 77.27 and 99.94 percent of Fe, Cu, Co and Mn were excreted through faeces. The requirements of Fe, Cu, Co and Mn were computed using the respective mineral balance data and were found to be 169.60, 7.20, 4.48 and 8.89 mg/kg respectively.

• Asian Journal of Turfgrass Science
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• v.9 no.3
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• pp.225-234
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• 1995

The Widespread and most abundant grasses are Miscanthus sinensis and Pteridium aquilinum in the grassland of Cheju-Island. The vascular flora of the grassland are composed of 127 species in all. Those communities of Miscanthus sinensis Pteridium aquilinum Imperata cylindrica Themeda japon-ica and Zoysia japonica are relatively homogeneous. Standing crops of the mixed grass communities range from 657 g /$m^2$ to 2, 975 g /$m^2$ on August 30, and the value of daily net production is around 2.6~121 g/$m^2$. The standing crop of north facing slop showed higher than that of south facing slop. Relationship between the standing crop and water content, organic matter, total nitrogen and available phosphorus of soils in Cheju-Island showed high level of significant.

• Advances in Traditional Medicine
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• v.5 no.4
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• pp.283-293
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• 2005

Our previous study showed that a novel synthetic shikonin derivative, 6-(1-hydroxyimino-4-methylpentyl)5,8-dimethyoxy 1,4-naphthoquinone S-52 (DMNQ S-52) induced apoptosis. In the present study, we investigated its anti-metastatic activities as compared with shikonin because DMNQ S-52 was synthesized for overcoming weak points of shikonin such as high toxicity, low solubility and deleterious effects. DMNQ S-52 showed the weaker cytotoxicity $(IC_{50};\;12.3{\pm}1.6\;{\mu}M)$ against Lewis lung carcinoma (LLC) cells than that of shikonin $(IC_{50};\;4.2{\pm}1.1\;{\mu}M)$. DMNQ S-52, at non-toxic concentrations $(less\;than\;10\;{\mu}M)$, significantly inhibited the invasion and migration of LLC cells. DMNQ S-52 also significantly inhibited the production of MMP-9, MTl-MMP and uPAR. Moreover, daily i.p. administration of DMNQ S-52 at dose of 5 mg/kg in mice resulted in a potent inhibition of the primary tumor size of LLC in the lung as well as the metastasis of lymph nodes. These findings suggest that the DMNQ S-52 has therapeutic potential to inhibit metastasis via inhibition of MMP family and uPA/plasminogen system.