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      • SCIESCOPUSKCI등재

        Nutrient Utilization, Body Composition and Lactation Performance of First Lactation Bali Cows (Bos sondaicus) on Grass-Legume Based Diets

        Sukarini,,I.A.M.,Sastradipradja,,D.,Sutardi,,T.,Mahardika,,IG.,Budiarta,,IG.A. Asian Australasian Association of Animal Productio 2000 Animal Bioscience Vol.13 No.12

        A study on energy and protein utilization, and milk production of Bali cows on grass-legume diets was carried out using 12 first lactation cows (initial BW $263.79{\pm}21.66kg$) during a period of 16 weeks starting immediately post calving. The animals were randomly allotted into 4 dietary treatment groups R1, R2, R3 and R4, receiving from the last 2 months of pregnancy onwards, graded improved rations based on a mixture of locally available grass and legume feed ad libitum. R1 contained on a DM basis 70% elephant grass (PP, Penisetum purpureum) plus 30% Gliricidia sepia leaves (GS), R2 was 30% PP plus 55% GS supplemented with 15% Hibiscus tilliactus leaves (HT, defaunating effect), R3 and R4 were 22.5% PP+41.25% GS+11.25% HT+25% concentrate, where R3 was not and R4 supplemented with zinc di-acetate. TDN, CP and zinc contents of the diets were 58.2%, 12.05% and 18.3 mg/kg respectively for R1, 65.05%, 16.9% and 25.6 mg/kg respectively for R2, 66.03%, 16.71% and 29.02 mg/kg respectively for R3 and 66.03%, 16.71% and 60.47 mg/kg respectively for R4. Milk production and body weight were monitored throughout the experimental period. In vivo body composition by the urea space technique validated by the body density method and supported by carcass data was estimated at the start and termination of the experiment. Nutrient balance and rumen performance characteristics were measured during a balance trial of 7 days during the 3rd and 4th week of the lactation period. Results indicated that quality of ration caused improvement of ruminal total VFA concentration, increments being 52 to 65% for R2, R3 and R4 above R1, with increments of acetate being less (31 to 48%) and propionate being proportionally more in comparison to total VFA increments. Similarly, ammonia concentrations increased to 5.24 to 7.07 mM, equivalent to 7.34 to 9.90 mg $NH_3-N/100ml$ rumen fluid. Results also indicated that feed quality did not affect DE and ME intakes, and heat production (HP), but increased GE, UE, energy in milk and total retained energy (RE total) in body tissues and milk. Intake-, digestible- and catabolized-protein, and retained-protein in body tissues and milk (Rprot) were all elevated increasing the quality of ration. Similar results were obtained for milk yield and components with mean values reaching 2.085 kg/d (R4) versus 0.92 kg/d (R1) for milk yield, and 170.22 g/d (R4) vs 71.69 g/d (R1), 105.74 g/d (R4) vs 45.35 g/d (R1), 101.34 g/d (R4) vs 46.36 g/d (R1) for milk-fat, -protein, and -lactose, respectively. Relatively high yields of milk production was maintained longer for R4 as compared to the other treatment groups. There were no significant effects on body mass and components due to lactation. From the relationship $RE_{total}$ (MJ/d)=12.79-0.373 ME (MJ/d); (r=0.73), it was found that $ME_{m}=0.53MJ/kgW^{0.75}.d$. Requirement of energy to support the production of milk, ranging from 0.5 to 3.0 kg/d, follows the equation: Milk Prod. ($Q_{mp}$, kg/d)=[-2.48+4.31 ME($MJ/kg^{0.75}.d$)]; (r=0.6) or $Q_{mp}$=-3.4+[0.08($ME-RE_{body\;tissue}$)]MJ/d]; (r=0.94). The requirement for protein intake for maintenance ($IP_m$) equals $6.19 g/kg^{0.75}.d$ derived from the relationship RP=-47.4+0.12 IP; (r=0.74, n=9). Equation for protein requirement for lactation is $Q_{nl}$=[($Q_{mp}$)(% protein in milk)($I_{mp}$)]/100, where $Q_{nl}$ is g protein required for lactation, $Q_{mp}$ is daily milk yield, Bali cow's milk-protein content av. 5.04%, and $I_{mp}$ is metabolic increment for milk production ($ME_{lakt}/ME_{m}=1.46$).

      • KCI등재SCIESCOPUS

        A 12-MHz CW RFQ for the AEBL Project

        D.,L.,Schrage,P.,N.,Ostroumov,A.,Barcikowski,D.,Fallin,A.,A.,Kolomiets 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.52 No.3

        The Advanced Exotic Beam Laboratory (AEBL) at the Argonne National Laboratory (ANL) will provide a research facility for studies of nuclear phenomena by using beams of short-lived isotopes for research on the nature of nucleonic matter and the origin of the elements, for tests of the Standard Model, for applications in medicine and industry, and for other applied physics research. The proposed design of the AEBL driver linac evolved from the Rare Isotope Accelerator (RIA) project. The AEBL will be a CW linac capable of accelerating uranium ions up to 200 MeV/u and protons to 580 MeV with 400 kW beam power. The AEBL facility also includes a post-accelerator which is designed for acceleration of radioactive ions with charge-to-mass ratios in the range from 1/238 to 1/6. Very low charge-state ions can be most eciently bunched and accelerated by using normally-conducting radio-frequency quadrupole (RFQ) for the rst few MV of the post accelerator. A two-meter long, 12-MHz CW RFQ was designed, built, and tested in the late 1990s as the rst section of a three-section RFQ [18]. This RFQ achieved inter-electrode voltages of 110 kV CW (the peak surface eld was 15 MV/m) and accelerated beams with A/q as large as 132 (132Xe). The AEBL requires a similar RFQ for the post-acceleration of singly-charged unstable nuclides. Our plan is to replace the vanes of this RFQ with a design that incorporates a stronger focusing and that will achieve a higher peak surface eld (16 MV/m) at 82.2-kV inter-vane voltage. The objectives of this project are 1. to conrm the possibility of a low injection energy of 0.4 keV/u which signicantly reduces the voltage required for a high-voltage deck; 2. to test the highest possible peak surface eld on the RFQ electrodes designed for the lowest frequency of 12 MHz compared to existing RFQs worldwide; 3. to provide a technical base for the design of a post-accelerator for the future Advanced Exotic Beam Facility. At the present time, the design is complete, and the fabrication of the 12 MHz RFQ is scheduled to commence in October 2007 with testing planned in 2008. The physics and engineering design of the RFQ is discussed. The Advanced Exotic Beam Laboratory (AEBL) at the Argonne National Laboratory (ANL) will provide a research facility for studies of nuclear phenomena by using beams of short-lived isotopes for research on the nature of nucleonic matter and the origin of the elements, for tests of the Standard Model, for applications in medicine and industry, and for other applied physics research. The proposed design of the AEBL driver linac evolved from the Rare Isotope Accelerator (RIA) project. The AEBL will be a CW linac capable of accelerating uranium ions up to 200 MeV/u and protons to 580 MeV with 400 kW beam power. The AEBL facility also includes a post-accelerator which is designed for acceleration of radioactive ions with charge-to-mass ratios in the range from 1/238 to 1/6. Very low charge-state ions can be most eciently bunched and accelerated by using normally-conducting radio-frequency quadrupole (RFQ) for the rst few MV of the post accelerator. A two-meter long, 12-MHz CW RFQ was designed, built, and tested in the late 1990s as the rst section of a three-section RFQ [18]. This RFQ achieved inter-electrode voltages of 110 kV CW (the peak surface eld was 15 MV/m) and accelerated beams with A/q as large as 132 (132Xe). The AEBL requires a similar RFQ for the post-acceleration of singly-charged unstable nuclides. Our plan is to replace the vanes of this RFQ with a design that incorporates a stronger focusing and that will achieve a higher peak surface eld (16 MV/m) at 82.2-kV inter-vane voltage. The objectives of this project are 1. to conrm the possibility of a low injection energy of 0.4 keV/u which signicantly reduces the voltage required for a high-voltage deck; 2. to test the highest possible peak surface eld on the RFQ electrodes designed for the lowest frequency of 12 MHz compared to existing RFQs worldwide; 3. to provide a technical base for the design of a post-accelerator for the future Advanced Exotic Beam Facility. At the present time, the design is complete, and the fabrication of the 12 MHz RFQ is scheduled to commence in October 2007 with testing planned in 2008. The physics and engineering design of the RFQ is discussed.

      • KCI등재SCOPUS

        Viator vitreocola gen. et sp. nov. (Stylonematophyceae), a new red alga on drift glass debris in Oregon and Washington, USA

        Gayle,I.,Hansen,John,A.,West,윤환수,Christopher,D.,Goodman,Susan,Loiseaux,de,Goër,Giuseppe,C.,Zuccarello 한국조류학회I 2019 ALGAE Vol.34 No.2

        A new encrusting red alga was found growing abundantly on glass debris items that drifted ashore along the coasts ofOregon and Washington. These included discarded fluorescent tubes, incandescent light bulbs, capped liquor bottles,and ball-shaped fishing-net floats. Field collections and unialgal cultures of the alga revealed that it consisted of twomorphological phases: a young loosely aggregated turf and a mature consolidated mucilaginous crust. The turf phaseconsisted of a basal layer of globose cells that produced erect, rarely branched, uniseriate to multiseriate filaments up to500 μm long with closely spaced cells lacking pit-plugs. These filaments expanded in size from their bases to their tipsand released single cells as spores. At maturity, a second phase of growth occurred that produced a consolidated crust,up to 370 μm thick. It consisted of a basal layer of small, tightly appressed ellipsoidal-to-elongate cells that generateda mucilaginous perithallial matrix containing a second type of filament with irregularly spaced cells often undergoingbinary division. At the matrix surface, the original filaments continued to grow and release spores but often also eroded. Individual cells, examined using confocal microscopy and SYBR Green staining, were found to contain a central nucleus,a single highly lobed peripheral chloroplast without a pyrenoid, and numerous chloroplast nucleoids. Morphologicaldata from field and culture isolates and molecular data (rbcL, psbA, and SSU) show that this alga is a new genus and specieswhich we name Viator vitreocola, “a traveller on glass.”

      • KCI등재후보SCOPUS

        The Impact of Feeding Diets of High or Low Energy Concentration on Carcass Measurements and the Weight of Primal and Subprimal Lean Cuts

        A.P.,Schinckel,M.E.,Einstein,S.,Jungst,J.O.,Matthews,B.,Fields,C.,Booher,T.,Dreadin,C.,Fralick,S.,Tabor,A.,Sosnicki,E.,Wilson,R.D.,Boyd 아세아·태평양축산학회 2012 Animal Bioscience Vol.25 No.4

        Pigs from four sire lines were allocated to a series of low energy (LE, 3.15 to 3.21 Mcal ME/kg) corn-soybean meal-based diets with 16% wheat midds or high energy diets (HE, 3.41 to 3.45 Mcal ME/kg) with 4.5 to 4.95% choice white grease. All diets contained 6% DDGS. The HE and LE diets of each of the four phases were formulated to have equal lysine:Mcal ME ratios. Barrows (N = 2,178) and gilts (N = 2,274) were fed either high energy (HE) or low energy (LE) diets from 27 kg BW to target BWs of 118, 127, 131.5 and 140.6 kg. Carcass primal and subprimal cut weights were collected. The cut weights and carcass measurements were fitted to allometric functions (Y = A CW^B) of carcass weight. The significance of diet, sex or sire line with A and B was evaluated by linearizing the equations by log to log transformation. The effect of diet on A and B did not interact with sex or sire line. Thus, the final model was cut weight = (1+b_D(Diet)) A(CW^B) where Diet = -0.5 for the LE and 0.5 for HE diets and A and B are sire line-sex specific parameters. Diet had no affect on loin, Boston butt, picnic, baby back rib, or sparerib weights (p>0.10, bD = -0.003, -0.0029, 0.0002, 0.0047, -0.0025, respectively). Diet affected ham weight (b_D = -0.0046, p = 0.01), belly weight (b_D = 0.0188, p = 0.001) three-muscle ham weight (bD = -0.014, p = 0.001), boneless loin weight (b_D = -0.010, p = 0.001), tenderloin weight (bD = -0.023, p = 0.001), sirloin weight (b_D = -0.009, p = 0.034), and fat-free lean mass (b_D = -0.0145, p = 0.001). Overall, feeding the LE diets had little impact on primal cut weight except to decrease belly weight. Feeding LE diets increased the weight of lean trimmed cuts by 1 to 2 percent at the same carcass weight.

      • SCIESCOPUSKCI등재후보

        Viator vitreocola gen. et sp. nov. (Stylonematophyceae), a new red alga on drift glass debris in Oregon and Washington, USA

        Hansen,,Gayle,I.,West,,John,A.,Yoon,,Hwan,Su,Goodman,,Christopher,D.,Goer,,Susan,Loiseaux-de,Zuccarello,,Giuseppe,C. The Korean Society of Phycology 2019 ALGAE Vol.34 No.2

        A new encrusting red alga was found growing abundantly on glass debris items that drifted ashore along the coasts of Oregon and Washington. These included discarded fluorescent tubes, incandescent light bulbs, capped liquor bottles, and ball-shaped fishing-net floats. Field collections and unialgal cultures of the alga revealed that it consisted of two morphological phases: a young loosely aggregated turf and a mature consolidated mucilaginous crust. The turf phase consisted of a basal layer of globose cells that produced erect, rarely branched, uniseriate to multiseriate filaments up to $500{\mu}m$ long with closely spaced cells lacking pit-plugs. These filaments expanded in size from their bases to their tips and released single cells as spores. At maturity, a second phase of growth occurred that produced a consolidated crust, up to $370{\mu}m$ thick. It consisted of a basal layer of small, tightly appressed ellipsoidal-to-elongate cells that generated a mucilaginous perithallial matrix containing a second type of filament with irregularly spaced cells often undergoing binary division. At the matrix surface, the original filaments continued to grow and release spores but often also eroded. Individual cells, examined using confocal microscopy and SYBR Green staining, were found to contain a central nucleus, a single highly lobed peripheral chloroplast without a pyrenoid, and numerous chloroplast nucleoids. Morphological data from field and culture isolates and molecular data (rbcL, psbA, and SSU) show that this alga is a new genus and species which we name Viator vitreocola, "a traveller on glass."

      • SCIESCOPUSKCI등재

        Daily Feed Intake, Energy Intake, Growth Rate and Measures of Dietary Energy Efficiency of Pigs from Four Sire Lines Fed Diets with High or Low Metabolizable and Net Energy Concentrations

        Schinckel,,A.P.,Einstein,,M.E.,Jungst,,S.,Matthews,,J.O.,Booher,,C.,Dreadin,,T.,Fralick,,C.,Wilson,,E.,Boyd,,R.D. Asian Australasian Association of Animal Productio 2012 Animal Bioscience Vol.25 No.3

        A trial was conducted to: i) evaluate the BW growth, energy intakes and energetic efficiency of pigs fed high and low density diets from 27 to 141 kg BW, ii) evaluate sire line and sex differences when fed both diets, and iii) to compare ME to NE as predictor of pig performance. The experiment had a replicated factorial arrangement of treatments including four sire lines, two sexes (2,192 barrows and 2,280 gilts), two dietary energy densities and a light or heavy target BW, 118 and 131.5 kg in replicates 1 to 6 and 127 and 140.6 kg in replicates 7 to 10. Pigs were allocated to a series of low energy (LE, 3.27 Mcal ME/kg) corn-soybean meal based diets with 16% wheat midds or high energy diets (HE, 3.53 to 3.55 Mcal ME/kg) with 4.5 to 4.95% choice white grease. All diets contained 6% DDGS. The HE and LE diets of each of the four phases were formulated to have equal lysine:Mcal ME ratios. Pigs were weighed and pen feed intake (11 or 12 pigs/pen) recorded at 28-d intervals. The barrow and gilt daily feed (DFI), ME (MEI) and NE (NEI) intake data were fitted to a Bridges function of BW. The BW data of each sex were fitted to a generalized Michaelis-Menten function of days of age. ME and NE required for maintenance (Mcal/d) were predicted using functions of BW (0.255 and 0.179 BW^0.60 respectively). Pigs fed LE diets had decreased ADG (915 vs. 945 g/d, p<0.001) than pigs fed HE diets. Overall, DFI was greater (p<0.001) for pigs fed the LE diets (2.62 vs. 2.45 kg/d). However, no diet differences were observed for MEI (8.76 vs. 8.78 Mcal/d, p = 0.49) or NEI (6.39 vs. 6.44 Mcal/d, p = 0.13), thereby indicating that the pigs compensated for the decreased energy content of the diet. Overall ADG:DFI (0.362 vs. 0.377) and ADG:Mcal MEI (0.109 vs. 0.113) was less (p<0.001) for pigs fed LE compared to HE diets. Pigs fed HE diets had 3.6% greater ADG:Mcal MEI above maintenance and only 1.3% greater ADG:Mcal NEI (0.152 versus 0.150), therefore NEI is a more accurate predictor of growth and G:F than MEI.Pigs fed HE diets had 3.4% greater ADG:Mcal MEI and 0.11% greater ADG:NEI above maintenance than pigs fed LE diets, again demonstrating that NEI is a better predictor of pig performance than MEI. Pigs fed LE diets had similar daily NEI and MEI but grew slower and less efficiently on both ME and NE basis than pigs fed HE diets. The data suggest that the midds NE value (2.132 Mcal/kg) was too high for this source or that maintenance was increased for pigs fed LE diets.

      • PE-010 : Activated Sorbent Hemosorption at Patients with Liver Failure

        ( D. Sh Saidkhanova ), ( B. A Saidkhanov ), ( Kh. G Khalikulov ) 대한간학회 2018 춘·추계 학술대회 (KASL) Vol.2018 No.1

        Aims: In the last decade extracorporal hemosorption is successfully applied to elimination of pathological changes after liver operations complications. Methods: The hemosorption method is applied at 22 patients with liver failure caused by biliary tract obturation and purulent cholangitis. At the same time at 14 patients hepatogenic encephalopathy was noted with heavy endogenic intoxication. After washing of a sorbent without preliminary geparinization of the patient the highway of a fence was connected to a vein. Results: The effectiveness of a hemosorption was estimated on clinical manifestations and data of laboratory analyses which were defined prior to the procedure, after 1 and 2 sessions of a hemosorption. Clinically at all patients after 1 session of a hemosorption significant improvement of a state with decrease of symptoms of intoxication of an organism is noted. The effectiveness of holding a procedure the sorbent modified by a neutral anolyte was much higher, than an unmodified analog. The clearance of toxiferous metabolites and main markers of endogenic intoxication was higher, than at patients of control group which the hemosorption was carried out by the same sorbent, but not activated solution of a neutral anolyte. After 2 sessions of a hemosorption at most of patients, along with a normalization of the studied biochemical indexes restitution of the immunologic status was noted. Conclusions: Thus, oxidizing modification of a sorbent allowed to increase effectiveness of treatment substantially at patients with liver failure.

      • KCI등재

        Immunomodulatory Properties of Frondoside A, a Major Triterpene Glycoside from the North Atlantic Commercially Harvested Sea Cucumber Cucumaria frondosa

        D.L.,Aminin,I.G.,Agafonova,V.I.,Kalinin,A.S.,Silchenko,S.A.,Avilov,V.A.,Stonik,P.D.,Collin,C.,Woodward 한국식품영양과학회 2008 Journal of medicinal food Vol.11 No.3

        Frondoside A, a major triterpene glycoside from North Atlantic commercially harvested sea cucumber Cucumaria frondosa, possesses strong immunomodulatory properties in subtoxic doses. Frondoside A stimulates lysosomal activity of mouse macrophages in vivo at a maximal effective stimulatory dose of 0.2 μg per mouse and is maintained over 10 days. This glycoside also shows a 30% stimulation of lysosomal activity in mouse macrophages in vitro at concentrations of 0.1–0.38 μg/mL. Frondoside A enhances macrophage phagocytosis of the bacterium Staphylococcus aureus in vitro at a maximal effective concentration of 0.001 μg/mL. Frondoside A stimulates reactive oxygen species formation in macrophages in vitro at a maximal effective concentration of 0.001 μg/mL. Frondoside A stimulates an increase in the number of antibody plaque-forming cells (normally B-cells in spleen) in vivo with a maximal stimulatory effect at a concentration of 0.2 μg per mouse (stimulatory index, 1.86). Frondoside A has a weak effect upon immunoglobulin (Ig) M production after immunization with sheep erythrocytes in mice. Frondoside A does not stimulate Ig production in mice and does not significantly enhance the ovalbumin-stimulated IgM and IgG antibody levels in ovalbumin-immunized mice. Hence frondoside A is an immunostimulant of cell-based immunity including phagocytosis without a significant effect on amplification of humoral immune activity or adjuvant properties. Therefore, frondoside A may provide curative and/or preventive treatment options against diseases wherein a depleted immune status contributes to the pathological processes.

      • KCI등재후보SCOPUS

        Daily Feed Intake, Energy Intake, Growth Rate and Measures of Dietary Energy Efficiency of Pigs from Four Sire Lines Fed Diets with High or Low Metabolizable and Net Energy Concentrations

        A.P.,Schinckel,M.E.,Einstein,S.,Jungst,J.O.,Matthews,C.,Booher,T.,Dreadin,C.,Fralick,E.,Wilson,R.D.,Boyd 아세아·태평양축산학회 2012 Animal Bioscience Vol.25 No.3

        A trial was conducted to: i) evaluate the BW growth, energy intakes and energetic efficiency of pigs fed high and low density diets from 27 to 141 kg BW, ii) evaluate sire line and sex differences when fed both diets, and iii) to compare ME to NE as predictor of pig performance. The experiment had a replicated factorial arrangement of treatments including four sire lines, two sexes (2,192 barrows and 2,280 gilts), two dietary energy densities and a light or heavy target BW, 118 and 131.5 kg in replicates 1 to 6 and 127 and 140.6 kg in replicates 7 to 10. Pigs were allocated to a series of low energy (LE, 3.27 Mcal ME/kg) corn-soybean meal based diets with 16% wheat midds or high energy diets (HE, 3.53 to 3.55 Mcal ME/kg) with 4.5 to 4.95% choice white grease. All diets contained 6% DDGS. The HE and LE diets of each of the four phases were formulated to have equal lysine:Mcal ME ratios. Pigs were weighed and pen feed intake (11 or 12 pigs/pen) recorded at 28-d intervals. The barrow and gilt daily feed (DFI), ME (MEI) and NE (NEI) intake data were fitted to a Bridges function of BW. The BW data of each sex were fitted to a generalized Michaelis-Menten function of days of age. ME and NE required for maintenance (Mcal/d) were predicted using functions of BW (0.255 and 0.179 BW^0.60 respectively). Pigs fed LE diets had decreased ADG (915 vs. 945 g/d, p<0.001) than pigs fed HE diets. Overall, DFI was greater (p<0.001) for pigs fed the LE diets (2.62 vs. 2.45 kg/d). However, no diet differences were observed for MEI (8.76 vs. 8.78 Mcal/d, p = 0.49) or NEI (6.39 vs. 6.44 Mcal/d, p = 0.13), thereby indicating that the pigs compensated for the decreased energy content of the diet. Overall ADG:DFI (0.362 vs. 0.377) and ADG:Mcal MEI (0.109 vs. 0.113) was less (p<0.001) for pigs fed LE compared to HE diets. Pigs fed HE diets had 3.6% greater ADG:Mcal MEI above maintenance and only 1.3% greater ADG:Mcal NEI (0.152 versus 0.150), therefore NEI is a more accurate predictor of growth and G:F than MEI.Pigs fed HE diets had 3.4% greater ADG:Mcal MEI and 0.11% greater ADG:NEI above maintenance than pigs fed LE diets, again demonstrating that NEI is a better predictor of pig performance than MEI. Pigs fed LE diets had similar daily NEI and MEI but grew slower and less efficiently on both ME and NE basis than pigs fed HE diets. The data suggest that the midds NE value (2.132 Mcal/kg) was too high for this source or that maintenance was increased for pigs fed LE diets.

      • KCI우수등재

        잔디 우점 초지에 있어서 Orchardgrass 의 정착에 미치는 경합요인에 관한 연구

        김동암 한국축산학회 1972 한국축산학회지 Vol.14 No.3

        A series of four separate experiments was conducted with the following major aimes. 1. To evaluate the occurrence of competition between existing Zoysia japonica and oversown pasture species under field conditions. 2. To examine the toxic effects of leachate produced from underground parts of Zoysia japonica in water cultures. 3. To determine the effects of root and shoot competition of Zoysia japonica on the establishment of orchardgrass seedlings in pot cultures. 4. To evaluate the roles of both soil moisture and nitrogen as root competitive factors between existing Zoysia japonica and oversown orchardgrass seedlings in pot cultures. These experiments were designated and described as Experiment 1 - Field Test, Experiment 2 - Water Culture Test, Experiment 3 - Pot Test and Experiment 4 - Pot Test. Three species, orchardgrass, ky 31 fescue and ladino clover were used in Experiment I, the above two grasses and Italian ryegrass were also used in Experiment 2 and only orchardgrass was used in Experiment 3 and 4 as test plants. However, as an aggressor plant, Zoysia japonica was used in all experiments. With one exception, three experiments were carried out in a semi-controlled vinyl house environment and all work was done at the Livestock Farm, College of Agriculture, Seoul National University, Suwon, Korea. The summarized results of each experiment are as follows; Experiment 1. A study of factors influencing grasses and clover establishment and survival on native pastures dominated by Zoysia japonica was made on infertile native grassland and also an evaluation was made of the occurrence of competition between existing Zoysia japonica and oversown pasture species. Nitrogen and lime (Ca(OH)₂) depressed significantly establishment of clover. Lime depressed clover establishment was probably initially due to a strong alkalization of surface soil. Lime, nitrogen and phosphorus had no significant effect on initial establishment of grasses in bath presence and absence of Zoysia japonica, but lime aided clover survival in both presence and absence of herbage cover and phosphorus aided survival of grasses in absence of cover. Dense herbage cover had little effect on clover establishment and survival, indicating no competition between clover and existing Zoysia japonica, but had a depressing effect on grass establishment and survival, indicating competition between sown grasses and Zoysia japonica. It is considered that failure of grasses to become established amidst dense Zoysia japonica may be attributed to competition from existing Zoysia japonica. Experiment 2. To determine the mechanism of root competition by Zoysia japonica experiments were carried out on the production of toxins from its underground parts. Zoysia japonica was used in the study mainly because of its reputation as a strong competition in a previous experiment. In these experiments to test the production of toxins from Zoysia japonica, seedlings of orchardgrass, ky 31 fescue and Italian ryegrass were treated with leachates of roots and rhizomes, and seeds and seedlings of the above grasses were germinated and grown in close contact with living Zoysia japonica roots. These experiments showed that there were no evidence of any appreciable growth promotion or inhibition by Zoysia japonica. Therefore, it is evident that the competition between Zoysia japonica and oversown grasses is not due to the production of toxic substances from Zoysia japonica. Experiment 3. The effects of root and shoot competition of Zoysia japonica on the ability of orchardgrass seedlings to become established in native pastures dominated by Zoysia japonica were studied. These studies were carried out during 1971 in vinyl house pot cultures using a split plat design, with three moisture levels imposed on five competition treatments including (1) full competition (2) root competition (3) shoot competition (4) no competition and (5) mono culture. Soil moisture treatments were; (1) plants watered to near field capacity when the Bouyoucous blocks reached a resistance of 3,700 ohms (low), (2) plants watered to near field capacity when the Bouyoucous blocks reached a resistance of 1,550 ohms (medium) and (3) plants watered to near field capacity when the Bouyoucous blocks reached a resistance of 530 ohms (high). Full competition and root competition treatments with Zoysia japonica significantly tended to reduce the top dry matter production, root dry weight and morphological characteristics of orchardgrass seedlings from those of shoot competition, no competition and mono culture treatments. Soil moisture levels had no significant effect on the dry matter production, shoot length and tiller production of orchardgrass seedlings under full competition and root competition treatments, however, under shoot competition, no competition and mono culture treatments a significant effect (P$lt;0.05) was found as the soil moisture level increases. The growth and development of orchardgrass seedlings was more severely affected under root competition, but more favoured under shoot competition from existing Zoysia japonica at the early stage of establishment. Therefore light appears not to be critical factor in the establishment of orchardgrass seedlings in existing Zoysia japonica native pastures. The results show that orchardgrass seedlings can be established in existing Zoysia japonica native pastures when favourable conditions of soil moisture and nutrients are maintained. Nevertheless, the growth of orchardgrass seedlings under full competition and root competition at high soil moisture was approximately two hundredth that of plants grooving in mono culture. Therefore, other nutrient factors as well as soil moisture may be operating in competition between Zoysia japonica and orchardgrass seedlings. The additive effect of competition for light and competition for moisture on the dry matter production and morphological characteristics of orchardgrass seedlings was not found in this experiment. Experiment 4. Orchardgrass seedlings were established in the soil in which the competing species, Zoysia japonica was already established. The effect of root competition on orchardgrass seedlings, as a test plant, was measured when two levels of soil moisture and nitrogen were supplied, and from half of orchardgrass seedlings root competition was excluded. Top and root dry matter production and morphological characteristics of orchardgrass seedlings were measured in a 2³ factorial design. Root competition significantly (P$lt;0.01) reduced the top and root dry matter production, tiller production, number of leaves, length and width of longest leaf of orchardgrass, But significantly (P$lt;0.01) increased top dry matter production of Zoysia japonica. The high levels of soil moisture and nitrogen did not completely eliminate the effects of root competition on the top and root dry matter production and morphological characteristics of orchardgrass seedlings, but the high levels of soil moisture and nitrogen had a little more effect than the low levels, suggesting competition for both soil moisture and nitrogen. For the top and root dry matter production of orchardgrass seedlings there were significant interactions (P$lt;0.01) between moisture and competition treatments. For the top and root dry matter production longest leaf and tiller production significant interactions (P$lt;0.05) have been found between nitrogen and competition treatments, but no interaction was found between nitrogen and soil moisture levels for all growth characteristics. It is deduced that competition from Zoysia japonica involves both soil moisture and nitrogen, and that soil moisture is probably the more important factor when orchardgrass is oversown into existing Zoysia japonica under natural conditions.

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