• Journal of Animal Science and Technology
• /
• v.51 no.5
• /
• pp.369-378
• /
• 2009

Protein fractionation was evaluated from whole crop silages of rye (RS), wheat (WS), triticale (TS), oat (OS), barley (BS), and rice straw silage (RSS), and in vitro trial was carried out to examine the effect of silage and extraction of soluble protein on fermentation characteristics, total gas production and degradation. Soluble protein of silages was extracted with borate-phosphate buffer, and fermentation characteristics, gas production and degradation of silages were estimated by incubating anaerobically the mixed solution of strained rumen fluid and artificial saliva (1:1, v/v) containing dried and ground silages placed in nylon bag at $39^{\circ}C$ up to 48h. Soluble protein (SP) content was lowest for RSS as 2.11% in total CP compared to those for other silages. Highest A fraction (NPN) was observed from RS (74.33% of total CP) while those from TS and RSS were relatively low (48%). B2 fraction was relatively higher for RS, RSS and WS than for TS and BS. $B_3$ fraction was lowest in WS among silages. C fraction (27.07) in RSS was higher than in other silages (1.40~9.93%). pH in incubation solution was increased (P<0.01~P<0.001) for extracted silages up to 12h but decreased (P<0.01) at 48h for non-extracted ones. Contents of ammonia-N (P<0.001) and total VFA (P<0.01~P<0.001) were higher for non-extracted silages than for extracted ones. Acetate proportion was increased (P<0.001) in buffer extracted silages while those of propionate and butyrate were decreased (P<0.001) up to 24h incubation. Increased (P<0.001) total gas production was obtained from non-extracted silages up to 12h while gas production was increased (P<0.01) in extracted ones thereafter. In vitro degradation of dry matter and CP was increased (P<0.001) in non-extracted silages but that of neutral detergent fiber was increased (P<0.001) in extracted ones without difference among silages. Difference in mean values of degradability for each silage prior to- and post extraction with borate buffer, however, was not found among silages. It may be concluded that high NPN content of silages may reduce the protein availability in silages and borate buffer soluble components in silages can stimulate the early stage of fermentation.

• Korean Journal of Weed Science
• /
• v.16 no.4
• /
• pp.264-281
• /
• 1996

As a consequence of wide use of herbicides, Eleocharis kuroguwai Ohwi became a dorminant problem weed for rice cultivation in Korea. To understand the establishment of the weed, experiments on physio-ecological characteristics were carried out sprouting and occurrence, the results could be summarized as follows: Sprouting percentage remained 68 to 73% until the time of field emergence, indicating many of the them are still dormant. The proportion of the dormant tubers were greater for the smaller than the bigger tubers. Apical dominance was apparent in sprouting, with 84% of tuber sprouted from only one of the apical buds. Tubers sprouted from 2 or 3 buds were less than 20%, and were mostly from the bigger tubers. When the shoot growth was compared, by controlling the others, ones from apical and the next 3 buds showed similar vigorous growth, but the later ones showed poorer growth. For the longevity of tubers, deep soil storage appeared to be better than storage in temperature controlled room to 2~$3^{\circ}C$. Emergence of E. kuroguwai was better in clay soil than in sand, and the possible depth for emergence in clay soil appeared to be up to 21cm, but was 15cm in sand. When tubers were exposed to salt solutions before emergence tests, E. kuroguwai appeared to be much sensitive to salts than S.planiculmis. Among the tubers formed in previous year, 12.7% remained still viable until the end of next crop season, but with relatively strong dormancy. The first emergence was about 10 days after planting at ordinary cropping seasons, and the days to the maximum shoot number stage were 60~90 from planting. The duration was extended at early transplanting, and shoot number, leaves per shoot, and tubers developed per plant were also greater at early plantings. The 6th order offshoots were developing when E. kuroguwai was planted at early season. When planted at later seasons, generation and the number of offshoots was reduced planted at early season. When planted at later seasons, generation and the number of offshoots was reduced and the number of tubers, runner and rhizome lengths was also reduced.

• Water for future
• /
• v.9 no.1
• /
• pp.38-42
• /
• 1976

Because of differences in thoughts and ideology, our country, Korea has been deprived of national unity for some thirty years of time and tide. To achieve peaceful unification, the cultivation of national strength is of paramount importance. This national strength is also essential if Korea is to take rightful place in the international societies and to have the confidence of these societies. However, national strength can never be achieved in a short time. The fundamental elements in economic development that are directly conducive to the cultivation of national strength can be said to lie in -a stable political system, -exertion of powerful leadership, -cultivation of a spirit of diligence, self-help and cooperation, -modernization of human brain power, and -establishment of a scientific and well planned economic policy and strong enforcement of this policy. Our country, Korea, has attained brilliant economic development in the past 15 years under the strong leadership of president Park Chung Hee. However, there are still many problems to be solved. A few of them are: -housing and home problems, -increasing demand for employment, -increasing demand for staple food and -the need to improve international balance of payment. Solution of the above mentioned problems requires step by step scientific development of each sector and region of our contry. As a spearhead project in regional development, the Saemaul Campaign or new village movement can be cited. The campaign is now spreading throughout the country like a grass fire. However, such campaigns need considerable encouragement and support and the means for the desired development must be provided if the regional and sectoral development program is to sucdceed. The construction of large multipurpose dams in major river basin plays significant role in all aspects of national, regional and sectoral development. It ensures that the water resource, for which there is no substitute, is retained and utilized for irrigation of agricultural areas, production of power for industry, provision of water for domestic and industrial uses and control of river water. Water is the very essence of life and we must conserve and utilize what we have for the betterment of our peoples and their heir. The regional and social impact of construction of a large dam is enormous. It is intended to, and does, dras tically improve the "without-project" socio-economic conditions. A good example of this is the Soyanggang multipurpose dam. This project will significantly contribute to our national strength by utilizing the stored water for the benefit of human life and relief of flood and drought damages. Annual average precipitation in Korea is 1160mm, a comparatively abundant amount. The catchment areas of the Han River, Keum River, and Youngsan River are $62,755\textrm{km}^2$, accounting for 64% of the national total. Approximately 62% of the national population inhabits in this area, and 67% of the national gross product comes from the area. The annual population growth rate of the country is currently estimated at 1.7%, and every year the population growth in urban area increases at a rising rate. The population of Seoul, Pusan, and Taegu, the three major cities in Korea, is equal to one third of our national total. According to the census conducted on October 1, 1975, the population in the urban areas has increased by 384,000, whereas that in rural areas has decreased by 59,000,000 in the past five years. The composition of population between urban and rural areas varied from 41%~59% in 1959 to 48%~52% in 1975. To mitigate this treand towards concentration of population in urban areas, employment opportunities must be provided in regional and rural areas. However, heavy and chemical industries, which mitigate production and employment problems at the same time, must have abundant water and energy. Also increase in staple food production cannot be attained without water. At this point in time, when water demand is rapidly growing, it is essential for the country to provide as much a reservoir capacity as possible to capture the monsoon rainfall, which concentarated in the rainy seaon from June to Septesmber, and conserve the water for year round use. The floods, which at one time we called "the devil" have now become a source of immense benefit to Korea. Let me explain the topographic condition in Korea. In northern and eastern areas we have high mountains and rugged country. Our rivers originate in these mountains and flow in a general southerly or westerly direction throught ancient plains. These plains were formed by progressive deposition of sediments from the mountains and provide our country with large areas of fertile land, emminently suited to settlement and irrigated agricultural development. It is, therefore, quite natural that these areas should become the polar point for our regional development program. Hower, we are fortunate in that we have an additional area or areas, which can be used for agricultural production and settlement of our peoples, particularly those peoples who may be displaced by the formation of our reservoirs. I am speaking of the tidelands along the western and southern coasts. The other day the Ministry of Agriculture and Fishery informed the public of a tideland reclamation of which 400,000 hectares will be used for growing rice as part of our national food self-sufficiency programme. Now, again, we arrive at the need for water, as without it we cannot realize this ambitious programme. And again we need those dams to provide it. As I mentioned before, dams not only provide us with essential water for agriculture, domestic and industrial use, but provide us with electrical energy, as it is generally extremely economical to use the water being release for the former purposes to drive turbines and generators. At the present time we have 13 hydro-electric power plants with an installed capacity of 711,000 kilowatts equal to 16% of our national total. There are about 110 potential dams ites in the country, which could yield about 2,300,000 kilowatts of hydro-electric power. There are about 54 sites suitable for pumped storage which could produce a further 38,600,000 kilowatts of power. All available if we carefully develop our water resources. To summarize, water resource development is essential to the regional development program and the welfare of our people, it must proceed hand-in-hand with other aspects of regional development such as land impovement, high way extension, development of our forests, erosion control, and develop ment of heavy and chemical industries. Through the successful implementation of such an integrated regional development program, we can look forward to a period of national strength, and due recognition of our country by the worlds societies.

• Journal of Animal Science and Technology
• /
• v.45 no.1
• /
• pp.101-112
• /
• 2003

This study was conducted to investigate the effect of the level of concentrates and pasture grazing in 60 head of spring born Hanwoo heifers(initial body weight; 125.3kg) for 450days from six to 21 months in age. Feeding trial was conducted with 5 treatment(twelve heads/ treatment) which were T1(1.5% of apparent body weight in concentrates and indoor feeding for over-all period), T2(0.5% of apparent body weight in concentrates for pre-pasture grazing and pasture grazing), T3(1.0% of apparent body weight in concentrates for pre-pasture grazing and pasture grazing), T4(1.5% of apparent body weight in concentrates for pre-pasture grazing and pasture grazing), T5(2.0% of apparent body weight in concentrates for pre-pasture grazing and pasture grazing). During the total experimental period, average daily gains by treatments ranged from 0.322 to 0.465kg(average 0.405kg) and higher in the order of T5, T4, T1, T3 and T2, and increased with the level of concentrates feeding for pre-pasture grazing. TDN intakes required per unit of kilogram gain were 9.13 to 9.79kg(average 9.49kg) higher in the order of T1, T3, T5, T4 and T2, For the grazing period, they were ranged from 12.39 to 12.98kg(average 12.68kg), and were not significantly different. But TDN requirements of grazing groups was higher about 15.6% than the indoor feeding group’s. The rate of roughage to concentrates by treatments were 57.8 to 73.6%(average 63.7%). The body weight of 15 and 21 month in ages, that is, the ages at puberty and first conception by treatments were 201.2 to 230.7kg(average 223.8kg) and 270.2 to 331.4kg (average 307.6kg), respectively, and the latter were high per unit of 20.4kg by increasing the level of concentrates feeding for pre-pasture grazing every 0.5% addition of apparent body weight. The age of 225 and 275kg in body weight, that is, the body weight at puberty and first conception by treatments were 14.0 to 17.6 month (average 15.3 month) and 17.9 to 21.7 month(average 19.4), respectively, and the latter were shorter about 1.3 month by increasing the level of concentrates feeding every 0.5% addition of apparent body weight. According to the above results, it may be concluded that spring born Hanwoo heifers are raised at indoor have to feed with 1.8% of body weight in concentrates under full feeding of rice straws for all period from six to 21 months in age, but with 1.5% of apparent body weight in concentrates for grazing period.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.15 no.3
• /
• pp.175-185
• /
• 1995

This experiment was carried out to investigate the optimum rates of animal excreta(cattle slurry-N) for the highest dry matter production and improve the nutritive values of reed canarygrass with different cutting frequency. The results are summarized as follows; The highest relative dry matter yields for annual dry matter yield were 42.2% and 45.2% at 3rd cut in 3 and 4 cuttings, and 34.7% at 4th cut in 5 cuttings, respectively. The annual dry matter yields of non slurry-N application plot showed were from 6.8 tons to 8.0 tons/ha in all cutting frequencies. The highest annual dry matter yield obtained was in 3 cuttings. The annual dry matter yield increased with an increase of applied rates of slurry-N in all cutting frequencies. Annual dry matter yield was produced by 3.3 tons/ha at rates of 90 kg N/ha/cut in 3 cuttings, and more 1.7 tonsha and 2.4 tons/ha at rates of 30 kg N/ha/cut in 4 and 5 cuttings than that of non slurry-N application plots. The contents of crude protein were 12.01% and 15.0% at rates of 90 kg N/ha/cut in 3 and 4 cuttings, and 16.59% at rates of 120 kg N/ha/cut in 5 cuttings, respectively. On the contrary, the content of acid detergent fibre(ADF) showed the lowest values at same rates of slurry-N application in each cutting. J. The average content of crude protein was significantly increased with cutting frequencies, and they were 11.43%, 13.53% and 15.53% in 3, 4 and 5 cuttings, respectively. The average contents of acid detergent fibre(ADF) were 40.27%, 40.53% and 37.06% in 3, 4 and 5 cuttings. The values of 5 cuttings were significantly lower than other cutting frequencies, but the values of acid detergent fibre(ADF) was not significantly different between 3 and 4 cuttings. 6. The efficiency of dry matter production to slurry-N application rates showed the highest values of 18.9 kg and 15.7 kg DM/kg N at rates of 30 kg N/ha/cut in 3 and 5 cuttings, and 16.3 kg DM/kg/ N at rates of 90 kg N/ ha/cut in 4 cuttings. The efficiency of total nitrogen yield to slurry-N application rates were the highest values of 0.51 kg and 0.43 kg W k g N at rates of 30 kg N/ha/cut in 4 and 5 cuttings, and 0.52 kg TN/kg N at rates of 90 kg N/ha/cut in 3 cuttings, respectively. 7. The ranges of economic slurry-N rates were estimated as the 107.2-151.0 kglha, 359.1-375.7 kgha and 160.3-236.9 kg/ha in 3, 4 and 5 cuttings, and marginal dry matter yields were 9.6-10.0 tons/ha, 12.4-12.6 tons/ha and 9.0-9.7 tons/ha in 3, 4 and 5 cuttings, respectively. 8. The limiting sluny-N application rates to maintain the highest dry matter yields were estimated to be 420.0 kg/ ha, 440.6 kg/ha and 666.3 kg/ha in 3, 4 and 5 cuttings.

• The Korean Journal of Food And Nutrition
• /
• v.25 no.2
• /
• pp.368-382
• /
• 2012

This paper investigated the system that is relevant to Jang(fermented soybean paste or solution), the relief of hunger-stricken people by Jang, 33 kinds of Jang, and its consumption in the documents, such as the annals of the Chosun Dynasty, Ihlseong-document, Seungjeongwon daily, Uigwe(record of national ceremony), official documents on the basis of Kyujanggak institute for the Korean studies and data base of Korean classics. There are lots of Jang named after the place of particular soybean's production from the ancient times. Jang, soybean, salt and Meju(source of Jang), during the Dynasty, were collected as taxation or tribute. In the 5th year of Hyeonjong(1664), the storage amount of soybean in Hojo(ministry of finance) was 16,200 $k{\ell}$, and its consumption was 7,694 $k{\ell}$ a year. In the 32nd year of Yongjo(1756), the 1,800 $k{\ell}$ of soybean was distributed to the people at the time of disaster, and in his 36th year(1756), the 15,426 $k{\ell}$ of soybean was reduced from the soybean taxation nationwide. The offices managing Jang are Naejashi, Saseonseo, Sadoshi, Yebinshi and Bongsangshi. Chongyoongcheong(Gyeonggi military headquarters) stored the 175.14 $k{\ell}$ of Jang, and the 198 $k{\ell}$ of Jang in Yebinshi. There are such posts managing Jang as Jangsaek, Jangdoo, and Saseonsikjang. In the year of Jeongjong(1777~1800), the royal family distributed the 3.6 $k{\ell}$ of Meju to Gasoon-court, Hygyeong-court, queen's mother-court, queen's court, royal palace. The 13.41 $k{\ell}$ of Gamjang(fermented soybean solution) was distributed to the Gasoon-court, 17.23 $k{\ell}$ to Hegyeong-court, 17.09 $k{\ell}$ to the queen's mother-court, and the 17.17 $k{\ell}$ to the queen's court each. There are 112 Jang-storing pots in the royal storages, and the 690 are in Namhan-hill, where the 2.7 $k{\ell}$ of fermented Jang was made and brought back by them each year. At the time of starvation, Jang relieved the starving people. There are 20 occasions of big reliefs, according to the annals of the Chosun Dynasty. In the 5th year of Sejong(1423), the 360 $k{\ell}$ of Jang was given to the hunger-stricken people. In his 6th year(1424), the 8,512.92 $k{\ell}$ of rice, bean, and Jang was provided and in the 28th year(1446), the 8,322.68 $k{\ell}$ of Jang was also provided to them. In the Dynasty, Jang was given as a salary. In case that when they were bereaved, they didn't eat Jang patiently for its preservation. They were awarded for their filial piety. In the annals of the Chosun Dynasty, there are 19 kinds of Jang. They are listed in the order of Jang(108), Yeomjang(90), Maljang(11), Yookjang(5), Gamjang(4), and etc.,. In Seungjeongwon daily, there are 11 kinds of Jang. Jang(6), Cheongjang (5), Maljang(5), and Tojang(3) are listed in order. In the Ihlseong-document, there are 5 kinds of Jang. They are listed in Jang(15), Maljang(2), Gamjang(2), and etc.,. There are 13 kinds of Jang in Uigwe, and the official documents, in the order of Gamjang(59), Ganjang(37), Jang(28), Yeomjang(7), Maljang(6), and Cheongjang(5). In addition, shi are Jeonshi(7), and Dooshi(4). All these are made of only soybean except, for Yookjang. The most-frequently recorded Jang among anthology, cookbook, the annals of the Chosun Dynasty, Ihlseong-document, Seoungjeongwon daily, Uigwe, or official document is Jang(372), and then Yeomjang(194), Gamjang(73), Cheongjang(46), Ganjang(46), Soojang(33), and Maljang(26), which were made of soybean. Jang from China in cookbook is not in anthology and royal palace documents. Thus, traditional Jang made of soybean was used in the daily food life in the royal court, and in the public during the Chosun period.

• The Korean Journal of Air & Space Law and Policy
• /
• v.30 no.2
• /
• pp.427-468
• /
• 2015

To date, we have considered the theoretical views, the standpoint of states and the discourse within the international community such as the UN Committee on the Peaceful Uses of Outer Space(COPUOS) regarding the Air/Outer Space Boundary Question which is one of the first issues of UN COPUOS established in line with marking the starting point of Outer Space Area. As above mentioned, discussions in the United Nations and among scholars of within each state regarding the delimitation issue often saw a division between those in favor of a functional approach (the functionalists) and those seeking the delineation of a boundary (the spatialists). The spatialists emphasize that the boundary between air and outer space should be delimited because the status of outer space is a type of public domain from which sovereign jurisdiction is excluded, as stated in Article 2 of Outer Space Treaty. On the contrary art. I of Chicago Convention is evidence of the acknowledgement of sovereignty over airspace existing as an international customary law, has the binding force of which exists independently of the Convention. The functionalists, backed initially by the major space powers, which viewed any boundary demarcation as possibly restricting their access to space, whether for peaceful or non-military purposes, considered it insufficient or inadequate to delimit a boundary of outer space without obvious scientific and technological evidences. Last more than 50 years there were large development in the exploration and use of outer space. But a large number states including those taking the view of a functionalist have taken on a negative attitude. As the element of location is a decisive factor for the choice of the legal regime to be applied, a purely functional approach to the regulation of activities in the space above the Earth does not offer a solution. It seems therefore to welcome the arrival of clear evidence of a growing recognition of and national practices concerning a spatial approach to the problem is gaining support both by a large number of States as well as by publicists. The search for a solution to the problem of demarcating the two different legal regimes governing the space above Earth has undoubtedly been facilitated and a number of countries including Russia have already advocated the acceptance of the lowest perigee boundary of outer space at a height of 100km. As a matter of fact the lowest perigee where space objects are still able to continue in their orbiting around the earth has already been imposed as a natural criterion for the delimitation of outer space. This delimitation of outer space has also been evidenced by the constant practice of a large number of States and their tacit consent to space activities accomplished so far at this distance and beyond it. Of course there are still numerous opposing views on the delineation of a outer space boundary by space powers like U.S.A., England, France and so on. Therefore, first of all to solve the legal issues faced by the international community in outer space activities like delimitation problem, there needs a positive and peaceful will of international cooperation. From this viewpoint, President John F. Kennedy once described the rationale behind the outer space activities in his famous "Moon speech" given at Rice University in 1962. He called upon Americans and all mankind to strive for peaceful cooperation and coexistence in our future outer space activities. And Kennedy explained, "There is no strife, ${\ldots}$ nor any international conflict in outer space as yet. But its hazards are hostile to us all: Its conquest deserves the best of all mankind, and its opportunity for peaceful cooperation may never come again." This speech seems to even present us in the contemporary era with ample suggestions for further peaceful cooperation in outer space activities including the delimitation of outer space.

• Journal of Animal Science and Technology
• /
• v.46 no.2
• /
• pp.261-272
• /
• 2004

This study was conducted to investigate indices affecting composts maturity for swine manure compost produced in a commercial composting facility with air-forced from the bottom. The composting was made of swine manure mixed with puffing rice hull(6: 4) and turned by escalating agitator twice a day. Composting samples were collected periodically during a 45-d composting cycle at that system, showing that indices of Ammonium-N to Nitrate-N ratio were sensitive indicators of composting quality. Pile temperature maintained more than 62$^{\circ}C$ and water contents decreased about 20% for 25days of composting. A great variety and high numbers of aerobic thermophilic heterotropic microbes playing critical roles in stability of composts have been examined in the final composts, sbowing that they were detected $10^8$ to $10^{10}$ $CFUg^{-1}$ in mesophilic bacteria, $10^3$ - $10^4$ in fungi and $10^6$ - $10^8$ in actinomycetes, respectively. The results of this study for detennining a factor affecting compost stability evaluations based on composting steps were as follows; 1. Ammonium-N concentrations were highest at the beginning of composting, reaching approximately 421mg/kg. However Ammonium-N concentrations were lower during curing, reaching approximately l04mg/kg just after 45 day. The ratio between $NH_4-N$ and $NO_3-N$ was above II at the beginning of composting and less than 2 at the final step(45 day). 2. Seed germination Index was dependent upon the compost phytotoxicity and its nutrition. The phytotocity caused the GI to low during the period of active composting(till 25 days of composting time) depending on the value of the undiluted. After 25 days of composting time, the GI was dependent upon compost nutrition. The Gennination index of the final step was calculated at over 80 without regard to treatments. 3. E4: E6 ratio in humic acid of composts was correlatively decreased from 8.86 to 6.76 during the period of active composting. After 25 days of composting time, the E4: E6 was consistently decreased from 6.76 to 4.67($r^2$ of total composting period was 0.95). 4. Water soluble carbon had a tendency to increase from 0.54% to 0.78%during the period of active composting. After 25 days of composting time, it was consistently decreased from 0.78% to 0.42%. Water soluble nitrogen increased from 0.22% to 0.32% during the period of 15 days after initial composting while decreased from 0.32% to 0.21% after 15days of composting. In consequence, the correlation coefficient($r^2$) between water soluble carbon and water soluble nitrogen was 0.12 during the period of active composting mule was 0.50 after 25 days of composting time

• Korean Journal of Poultry Science
• /
• v.7 no.2
• /
• pp.54-76
• /
• 1980

A survey was conducted to determine the status of health and productivity of poultry farms in Korea. Area included Was Kyunggido where exist nearly 50% of national poultry population. From this area, 41 layer and 34 broiler farms covering 21 Countries were selected randomly for the survey. When farms were divided in the operation size, 95.1% of layer and 82.3% of broiler farms were classified as business or industrial level while the rest were managed in a small scale as part time job. Generally layer farms had been established much earlier than broiler farms. Geographically 10.7% of layer farms were sited near the housing area such as field foreast and rice field. No farms were located near the seashore. The distance from one farm from the other was very close, being 80% of the farms within the distance of 1km and as many as 28% of the farms within loom. This concentrated poultry farming in a certain area created serious problems for the sanitation and preventive measures, especially in case of outbreak of infectious diseases. Average farm size was 5,016${\times}$3.3㎡ for layers and 1,037${\times}$3.3㎡ for broilers. 89.5% of layer ana 70.6% of broiler farms owned the land for farming while the rest were on lease. In 60% of layer farms welters were employed for farming while in the rest their own labour was used. Majority of farms were equipped poorly for taking necessary practice of hygiene and sanitation. The amount of disinfectant used by farms was considerably low. As many as 97.6% of lave. farms were practised with Newcastle(ND) and fowl pox(F$.$pox) vaccine, whereas only 43.6% and 5.1% of broiler farms were practised with ND and F$.$pox vaccine, respectively. In 17-32.7% of farms ND vaccine was used less than twice until 60 days of age and in only 14.6% of farms adult birds were vaccinated every 4months. Monthly expense for preventive measures was over 200,000W in 32% of farms. Only 4.9-2.7% of vaccine users were soaking advice from veterinarians before practising vaccination, 85% of the users trusted the efficacy of the vaccines. Selection of medicine was generally determined by the farm owner rather than by veterinarans on whom 33.3% of farms were dependant. When diseases outbroke, 49.3% of farms called for veterinary hospital and the rest were handled by their own veterinarians, salesmen or professionals. Approximately 70% of farms were satisfied with the diagnosis made by the veterinarians. Frequency of disease outbreaks varied according to the age and type of birds. The livabilities of layers during the period of brooding, rearing ana adultwere 90.5, 98.9 and 75.2%, respectively while the livalibility of broilers until marketing was 92.2%. In layers, average culling age, was 533.3 day and hen housed eggs were 232.7. Average feed conversion rates of layers and broilers were 3.30 and 2.48, respectively. Those figures were considerably higher than anticipated but still far lower than those in developed countries.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.18 no.2
• /
• pp.79-88
• /
• 1998

This experiment was conducted from May to August in 1997 to selected the wrn hybrids being suitable for silage at farm in the Kongju National University through the comparison of growth characteristics, forage yield and growth analysis about native and imported corn hybrids for silage production. In this experiment, trial design was a randomized block design with three replication, testing varieties were 4 hybrids (Suwon 19, Kwanganok, Whengsungok, Suwonok ) of native corn hybrids and 13 hybrids (P 3156, P 3352, P 3144w, DK 501, DK 689, DK 713, DK 729, H 643.99, H 545.64, H 645.12, HC 7466, H 644.18, H ALISEO) of imported corn hybrids. The results obtained are summarized as follows; 1. The emergence rate of H643.99 was the highest with 97.0%. In rice black streaked dwarf virus(RBSOV), the hybrid of HC 7466 was lower infected with 1.6% than other hybrids. The plant hight of P 3144w was the highest with 339 cm and the stem length of P 3156 was the highest with 261 cm. In native com hybrids, the plant height and stem length of Kwanganok were recorded with 306 cm and 235 cm, respectively. 2. Leaf number and leaf area of Kwanganok were the greatest with 16 sheet per plant and $5,180\;{\textrm{m}^2}/l0a$, respectively. H 645.12 and H 545.64 had the greatest in ear to total dry matter ratio with 49.5% and 49.4%, respectively. 3. The fresh matter yield was significantly difference between growth stage, So Suwon 19 had the most level at 15 days before silking, P 3352 had the most level at silking date, Kwananok had the most level at 35 days a after silking. The fresh matter yield of native com hybrids such as Suwon 19 and Kwanganok was not apparent diffreences as compared with imported corn hybrids. 4. As the results of survey with dry weight, the quantity of dry matter accumulation were increase after silking. The varieties of P 3352, P 3156, Kwanganok, OK 713 were more quantity of dry matter production than DK 501, HC 7466. The Kwanganok of native com hybrid and Pioneer strain with high percentage of dry matter were higher dry weight than Limagrain strain. 5. HC 7466 had the largest LAR with $6.53\;{\textrm{cm}^2}/g$, H545.12 had the lowest LAR with $3.30\;{\textrm{cm}^2/g}$. P 3144 had the largest LAI, DeKalb strain including DK 713 were larger apparently than Limagrain strain including HC 7466 with 3.15. 6. The RGR of testing varieties was little difference of statistical significantly, but DK 501, and HC 7466 were lower than other corn hybrids. The CGR of native and American varieties was no apparent differences, but that of Limagrain strains were a large variation. According to the results obtained by this experiment, the eary growth such as emergence rate and RBSDV infection rate of Limagrain strains was more excellent than other strains. P 3156, P 3352, P 3144w, DK 713 and HC 7466 were suitable for silage condition such as dry matter yield, percentage of dry matter and % ear to total dry matter. The fresh and dry matter yield of native corn hybrids such as Suwon 19 and Kwanganok were not apparent differences as compared with imported corn hybrids, but percentage of dry matter was lower than other imported corn hybrids.