• Korean Journal of Weed Science
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• v.1 no.1
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• pp.5-14
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• 1981

Weed is one of the problems in the crop land as well as in uncultivated land, raising the farm management costs. Therefore, the weed control is essential for effective agricultural management. The cost for weed control in Korea occupies on the average 27.6% of the total labor cost required. Agricultural policies since 1960 were transferring from yield increase due to land productivities to increase of income due to labor productivities. Therefore, the weed control by hand is also changed to weed control by chemicals. The weed control by chemicals has also brought about some side-effects and needs better, improved weed control methods. The present weed control situation and related problems were studied to present new approaches for agricultural development in the future. There were 458 species of weeds in 82 families which were growing in the crop land. The weeds to control, however, are 12 in paddy field and 9 in upland. So far weeds in paddy field are well under control, while weeds in upland are poorly controlled due to change in chemical efficiency and chemical damage in the upland. The administration, research and extension work for the efficient use of agricultural chemicals have been done by various institutions, such as Office of Rural Development, Office of Forestry, and chemical companies. The courses for agricultural chemicals were offered in the agricultural colleges. However, the efficiency of chemicals could not be maximized due to the poor relationships among related institutes. The newly established Agricultural Chemical Research Center at the Office of Rural Development and the Korean Weed Science Association are expected to contribute toward improving weed control in Korea. The Korean agriculture in the future will eventually be mechanized and the varieties resistant to high nitrogen application and to high plant density will be required for high yields. The rice will be transplanted earlier and the whole growing period will be extended. The application of organic matter will be increased for increasing soil fertility, and the use of agricultural chemicals will be continued. Under such a condition, the studies on the weed occurrence and its integrated control measures will be needed. Also weed controls in the newly exclaimed land, crop varieties, horticultural varieties, forage crops, and forests are also needed to study. Basic and practical researches for the weed control to improve the labor productivity will be also needed. In order to meet the all requirements for efficient weed control, weed control systems including all the academics, research and extension workers, administratives, farmers and companies should be established. Also securing researchers and education of personnels are pre-required and research funds for the chemical studies should be provided efficiently and timely.

• Korean Journal of Poultry Science
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• v.35 no.1
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• pp.15-20
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• 2008

This study aimed at evaluating the effects of a molting diet method in molt induction and post-molt performance of laying hens. Eighty-one ISA Brown hens at 62 wk of age were randomly divided into three groups. After a 4-wk preliminary period, a control group was fed a corn-soybean-based layer diet, and for the other groups, molting was induced by starvation (MS) or feeding a molting diet (MD). For the MS group, feed was withdrawn for 2 wk; this was followed by feeding a layer diet every other day for 1 wk and then the control diet. The MD group was fed a molting diet containing low-protein and low-energy diet based for 4 wk; this was followed by feeding a layer diet. They had a free access to their diet and water. Egg production, egg quality, feed intake, and ovary and oviduct weights were measured throughout the experimental period. During molting, the feed intake in the MD group was lower than that of the control. Body weight of the molted groups was significantly reduced. The MS group feeding totally ceased egg production within 4d; after the initiation of feeding and decreased; in the MD group, egg production to 9.3% by d 10. On d 14, the ovaries and oviducts of the molted groups were distinctly lighter than those of the control. Throughout the post-molt period, egg production and egg shell thickness of the molted group improved; but there were no significant differences. Eggs from the MD-fed or control group were heavier than those of the MS-fed or control group. Finally, feeding of a low-protein and low-energy diet effectively induces molting and increase post-molt production, but further research will be conducted to determine the effects of the molt diet with other ingredients and to reduce the energy level of the molt diet for maximizing molt induction and post-molt egg quality.

• Journal of Life Science
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• v.18 no.11
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• pp.1521-1531
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• 2008

After pigs was fed by commercial diets supplemented with various concentrations (0, 0.5, 1, and 1.5%) of the fermented mushroom by-product of Pleurotus eryngii, the meat qualities and the serum lipid compositions of the individual pig groups were investigated. The levels of total lipid, total cholesterol, and triglyceride in the serum were significantly lower when the pigs were fed with the diet supplemented with 1.5% fermented mushroom by-product than those of the control pigs. HDL-, LDL-, and VLDL-cholesterol contents in the serum exhibited no significant difference between the pig group fed by the diet containing the fermented mushroom by-product and the control group. In comparison to the control group, the pig group fed by the diet supplemented with 1.5% fermented mushroom by-product showed significantly lower level of AI, CRF, GOT, and LDH values in the serum, whereas the difference in the level of antioxidant activity of the serum was not significant. Sensory evaluation regarding color, off-flavor, tenderness, juiciness, and overall acceptability also showed that the pork from the pig group fed by the diet supplemented with the fermented mushroom by-product ($0.5{\sim}1.5%$) was better than that from the control group. Although enhancement in the lghtness ($a^*$) value of the pork was significant in 20 days of storage at $4^{\circ}C$, the redness ($L^*$) value was not significantly differential during the storage periods regardless of the supplementation of the fermented mushroom by-product into the diet. The cooking loss of the pork from the pig group fed by the diet supplemented with the fermented mushroom by-product (1% and 1.5%) decreased in the storage 10 days, but it increased in the storage 20 days. After storage for 20 days at $4^{\circ}C$, shear force of the pork obtained from the pigs fed by the diet supplemented with $1%{\sim}1.5%$ fermented mushroom by-product appeared to become significantly lower than that of the control. There were, however, no significant changes between two groups in the level of moisture content, crude lipid, and pH during the storage period. Although the TBARS content was enhanced in all groups during the storage period, the enhancement appeared to be more significant in the pork from the pig group fed by the diet containing the fermented mushroom by-product in comparison to the control. On the other hand, the ratio of UFA/SFA for the pork obtained from the individual pig groups showed no considerable diet-associated alterations during the storage period.

• Food Science of Animal Resources
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• v.26 no.4
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• pp.454-463
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• 2006

This study was carried out to investigate the effects of addition of green tea extract material with or without nitrite (0.02 g) on the quality characteristics and reduced nitrite content of emulsion-type sausages during 4 weeks of storage at $4^{\circ}C$. The treatments were; non-added nitrite and green tea extract (0, added nitrite and non-added green tea extract (T1), added nitrite and 0.2% green tea extract (T2), added nitrite and 0.5% green tea extract (T3), and added nitrite and 1% green tea extract (T4). The lightness $(L^*)$ of sausage containing nitrite and green tea extract together were significantly lower than control and T1 (p<0.05). The redness $(a^*)$ of sausage containing only nitrite (T1) and, nitrite and green tea extract at 1% (T4) were significantly higher than control (p<0.05). The total expressible fluid (%) of sausage containing nitrite and green tea extract were significantly lower than control (p<0.05). Cohesiveness of sausage containing green tea extract were significantly lower than control (p<0.05) at 2 and 4 weeks storage period. Addition of nitrite and green tea extract decreased the TBARS values (p<0.05). It was also found that natural extract (green tea) treatments decreased TBARS formation more than only added nitrite (Tl) (p<0.05). The changes of total plate count and coliform plate count were increased during storage time. The total plate count of T1 was higher at 4 weeks of storage period, while the coliform plate count was higher in control at 2 and 4 weeks of storage period compare to other treatments. The residual nitrite content was decreased during storage time in all treatment except control and the effectiveness of decreasing ability was higher with increasing green tea extract.

• Food Science of Animal Resources
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• v.27 no.2
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• pp.163-170
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• 2007

The effects of olive oil on the quality characteristics of pressed ham were investigated. Five different treatments were carried out varying the amount of olive oil added to pressed ham. for the control, 10% back fat among the total ham components was added without any olive oil. For the first treatment, 5% olive oil within the lard component was added into the pressed ham. The 2nd, 3rd and 4th treatments included 10%, 15% and 20% olive oil, respectively. Manufactured pressed hams containing olive oil were vacuum packaged and then stored for 28 days at $4^{\circ}C$. The crude protein and crude fat were not significantly different between the control and olive oil treated hams. The moisture and crude ash contents of olive oil treated hams was significantly lower than that of the control(p<0.05). There was no significant difference in pH between the control and olive oil treated hams. The pH increased during the first 7 days of storage and then decreased somewhat for the remainder of the 28 day storage period for all treatments. The meat color $b^*$ value of olive oil treated hams was higher than that of the control, whereas the meat color $a^*$ value decreased with the inclusion of olive oil. Neither value changed during the period of storage. There was no significant difference in texture between the control and olive oil treated hams throughout the storage period. In summary, pressed ham manufactured with added olive oil showed no change in physico-chemical properties and texture characteristics. Thus, it may be assumed that high quality pressed ham can be manufactured with increased monounsaturated fatty acid content.

• Korean Journal of Poultry Science
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• v.39 no.3
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• pp.183-193
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• 2012

This study was conducted to investigate the effect of feeding the electrolytic materials on blood and carcass traits of broiler during transportation exposed under intense heat condition in summer. The broilers were selected on the day when the outside temperature was about $32^{\circ}C$ to provide heat stressed environment. Broilers reared for 33 d were selected and fed with the electrolytic materials ($NaHCO_3$, NaCl, KCl) for 2 days. Treatments were as follows; feeding the underground water for control, $NaHCO_3$ (1.0%) + NaCl (0.5%) for treament 1, KCl (0.5%) + NaCl (0.5%) for treatment 2, KCl (1.0%) + NaCl (0.5%) treatment 3, KCl (0.5%) + $NaHCO_3$ (1.0%) + NaCl (0.5%) for treatment 4 and KCl (1.0%) + $NaHCO_3$ (1.0%) + NaCl (0.5%) for treament 5. pH of chicken meat increased for treatments group of electrolytic material, especially, that of treatment 3 was highest when compared to the other treatments. The frequency rate (%) of $1^+$ quality grade were 33.3, 60.0 and 83.3% at control, treatment 3, 4 and treatment 5, respectively. Occurrence rates of PSE were 50% for control and 13.3% for treatment 5. Corticosterone increased at the post-harvest period compared to the pre-harvest period of broiler and have small disparity between pre-and post-harvest only except treatment 3 when compared to control. $pCO_2$ partial pressure of blood at the pre-harvest period was low in all treatments by heat stress, the disparity value of control was high for control, and those of treatment 4 and 5 were low compared to other treatments.

• Journal of Ginseng Research
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• v.1 no.1
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• pp.33-50
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• 1976

As a continuation of series of works on the pharmacological actions of Panax ginseng. three kinds of behavioral experiments were carried out using rats and mice. The occurrence of component Posterns of general behavioral activity in rat was examined by visual scanning using the ting sample method in the ad lib. And he hunger deprivated situation. In normal ad lib. situation, the eating behavior of rat treated with 100mg/kg of ginseng saponin was significantly more frequent than that of saline control at the night and throughout the 24 hr period. But grooming was less frequent than the control at the same period. In the hunger situation followed by 90~120 hrs of feed deprivation, the locomotive activity and rearing awe significantly more often and sleeping was less frequent in the two dosage g roups of ginseng saponin (10 and 100 mg/kg) than in the saline group though out the observation period. Training of avoidance conditioning in rats was done in a two-way shuttle box. The number of conditioned response (CR) in which the animal avoided sucessfully an electric shock by running in to the other compartment of the hex was regarded as an index of learning performance. Ginseng saponin in doses of 2.5 mg/kg Produced a significantly increased CR in total avoidance tria1s compared with the control. Although other dosage groups of ginseng saponin (5.0, 50mg and 100 mg/kg) showed no significant statistical difference from the normal control, it tended to increase in CR in the ginseng groups than in the control. An aggressive behavior in mice was observed in n shock-generating fighting box. The occurrence of reflexive fighting between two animals induced by an electric shock applied to the feet war checked as an index of aggression. The occurrence of reciprocal fighting episode immediately after the onset. Of the shock was significantly decreased in the dosage group of 400 mg/kg ginseng saponin, but it did net differ in the 100 mg/kg group of ginseng saponin from the control group. The dose, 400 mg/kg of ginseng saponin, inhibited fighting behavior in more than 80% of the Pairs. but 100 mg/kg of ginseng did inhibit it in less than 20% of the pairs.

• Journal of The Korean Society of Grassland and Forage Science
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• v.36 no.2
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• pp.81-88
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• 2016

This study was conducted to find out the effects of Improvement of Botanical Composition Technology (IBCT) on the forage production and ecological characteristics in a Rumex acetosella-dominated hilly pasture in Pyeongchang, in a period from August 2013 to the end of growing season in October 2015. $2MT\;ha^{-1}$ limestone was applied in August 2013 and April 2014. Liming significantly increased soil pH from 4.69 to 5.47 and then the soil pH consistently hovered at 4.91~4.98. For every grazing time, plant height was found to be higher with the application of IBCT as compared with the control. After grazing, no significant difference in plant height was found between the IBCT group and the control. Changes in the botanical composition of grassland can be affected by a lot of circumstances, but application of IBCT decreased Rumex acetosella from 12% to 2%, while also increasing the proportion of pasture. In relation to the botanical composition of grass, orchardgrass and timothy showed the highest percentages throughout the whole study period. The proportion of Kentucky bluegrass increased over time while tall fescue steadily decreased. The totals for grazing days were 58 in 2014 and 55 in 2015. Average herbage dry matter intake was $7,848kg\;ha^{-1}$ in 2014 and $6,941kg\;ha^{-1}$ in 2015. Due to the application of IBCT, dry matter productivity showed a significant increase of 59% during the first grazing period in 2014 (3,437 kg ha and 5,460 kg ha in control and IBCT). In 2015, the total dry matter yield of the IBCT group was 51% greater than the control ($5,742kg\;ha^{-1}$ and $8,685kg\;ha^{-1}$ in control and IBCT). Under acidic soil conditions, red sorrel can grow more strongly than grasses because it has better tolerance in dry and acidic conditions. Therefore, constant management is required in order to keep red sorrel from dominating the hilly pasture. In this study, the application of IBCT was able to effectively control weeds at all points. As a result, total management, including improvement of soil, overseeding, and application of selective herbicide and fertilizer, is needed to maintain excellent grassland conditions due to the limiting effects of environmental factors on grassland productivity.

• Food Science of Animal Resources
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• v.28 no.4
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• pp.480-485
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• 2008

In this experiment, 5 treatments consisted of control, probiotics (0.2%; T1), illite (1.0%; T2), activated carbon (1.0%; T3), and hardwood vinegar (1.0%; T4) as diets of chicken were evaluated for 35 days through feeding of 200 male chickens (Arbor Acre Broiler). Thigh muscle from slaughtered chickens were analyzed on pH, volatile basic nitrogen (VBN), thiobarbituric acid reactive substance (TBARS), shear force, and meat color during 10 d of cold storage at $4{\pm}1^{\circ}C$. Groups of T3 and T4 showed higher pH levels compared to the control group, and T4 showed significantly higher value. Over the storage period, all treatment groups showed increase in pH (p<0.05). Values of VBN of T1, T3, and T4 were lower than those of the control group and T2 up to 7 d of storage (p<0.05), but there was no significance at 10 d of storage. Values of TBARS of T3 and T4 were lower than the control group, T1, and T2, while all treated groups showed rapid increase of TBARS values over storage period (p<0.05). Shear force did not show significant difference among treated groups, but it was decreased over storage. Lightness of meat color (L) in treated groups was higher than the control, and T4 showed the highest value during entire storage period (p<0.05). Yellowness levels (b) of T3 and T4 were higher than the control group. These results may suggest the improvement of chicken meat quality and shelf life via the addition 1% activated carbon and 1% hardwood vinegar into feed.

• Clinical and Experimental Reproductive Medicine
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• v.11 no.2
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• pp.41-49
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• 1984

It has been well known that ovarian steroids, estradiol and progesterone play an important role in the endometrial preparation for the implantation process. The present investigation was undertaken to correlate function of ovarian steroids with cAMP concentrations in uterine tissues of rat during the various stages of the preimplantation period. Rats ovariectomized on day 2 were treated with estradiol or/and progesterone on day 3 or on day 4 and cAMP concentrations in uterine tissues were determined by competitive protein - binding assay in control - and steroid treated - ovariectomized rats. The results obtained are as follows; 1. In control rats, cAMP concentrations in uterine tissues were decreased with preimplantation period proceeded whereas cAMP concentrations were increased and showed the highest levels on day 6 in ovariectomized rats. 2. In rats treated with progesterone only or progesterone with estradiol after ovariectomy, cAMP concentrations on day 6 were lower than those of ovariectomized control but higher than those of intact control rats while estradiol only treatment decreased cAMP concentrations on day 3 and day 6, compared with those from intact- and ovariectomized-controls. It is, therefore, concluded that the concentrations of cAMP in uterine tissues were lower in estrogen-treated rats than in ovariectomized rats, suggesting the involvement of cAMP in the regulation of uterine tissue differentiation.