• Asian-Australasian Journal of Animal Sciences
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• v.10 no.2
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• pp.170-177
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• 1997

Two experiments were conducted to evaluate the effects of different extrusion conditions of corn and soybean meal on physico-chemical properties, ileal digestibility of amino acid and growth performance in weaned pigs. In Expt. 1, to compare physico-chemical properties and ileal digestibility of extruded corn and soybean meal, ground corn (2 mm screen) and soybean meal were separately extruded in four different conditions: (1) no preconditioning, low water supply (3.0 l/min) (NCLW), (2) no preconditioning, high water supply (7.0 l/min) (NCHW). (3) preconditioning (steam 3.0 l/min) with low water supply (3.0 l/min) (CLW), and (4) preconditioning (steam 3.0 l/min) plus high water supply (7.0 l/min) (CHW). Twenty-five cannulated pigs ($L{\times}Y{\times}D$, 7.62 kg BW for soybean meal, 8.80 kg BW for corn) were employed to determine nutrients digestibility of the extruded feedstuffs. In Expt. 2, a total of 90 pogs ($L{\times}Y{\times}D$, 9.18 kg BW) were used for a 28 d feeding trial to compare growth performance of pigs as affected by different extrusion conditions. Before mixing, corn and soybean meal were blended and extruded by the same conditions as described in Expt. 1. corn extruded with NCLW showed the highest (p < 0.05) degree of gelatinization (DG), compared to the lowest values observed for NCHW. Extrusion of corn with preconditioning (CLW and CHW) increased (p < 0.05) the DG as compared to the extrusion condition of NCHW. Extruded SBM with NCLW showed the lowest (p < 0.05) degree of texturization among treatments. The ileal digestibility of GE in SBM was higher with NCHW and CHW as compared to NCLW. The ileal digestibility of CP was lower in extruded corn, but was higher in extruded SBM, compared to untreated sample. Lysine digestibility of extruded corn (except corn with NCHW) was in general significantly improved. Extrusion of SBM resulted in no improvements in ileal digestibility of amino acids, but extruded SBM with NCLW had lower lysine digestibility compared to other treatments. In growth responses, pigs fed a diet with CLW had higher, but not significant, average daily gain (ADG) than other treatments during first 2 weeks. From d 15 to 28, pigs fed a diet with CHW had significantly less (p < 0.05) average daily feed intake (ADFI) than others except NCHW. In conclusion, the proper extrusion condition for corn and SBM in terms of ileal digestibility of amino acids and growth performance of weaning pigs seems to be the combination of preconditioning and a low water supply (3.0 l/min).

• Journal of Animal Science and Technology
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• v.55 no.2
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• pp.109-113
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• 2013

The aim of the present study was to investigate the effects of partial substitution of an extruded or extruded-pelleted corn product for unprocessed corn of the starter diet on growth performance and incidence of diarrhea in weanling pigs. Seventy-two 21-day-old weanling pigs were allotted to 24 pens and provided ad libitum with one of the four experimental diets for 3 wk in two serial feeding trials during summer beginning from late June. The treatments were a milk product-soy-corn-based control diet containing 25% unprocessed corn and the other three diets only substituted with 12.5% extruded corn Suprex$^{(R)}$, Optigrain$^{(R)}$, an extruded mixture of wheat, rye and durum, or extruded-pelleted corn for an equal percentage of unprocessed corn of the control diet. All diets were supplemented with 100 ppm sulfathiazone, 50 ppm penicillin, and 100 ppm chlortetracycline for preventive medication. The initial and final weights as well as gain : feed were less in the second trial than in the first one (P<0.05). However, effects of the dietary treatments were not detected in any of the performance variables including final weight, ADG, ADFI, and gain : feed, nor were there any interactions between the trial and dietary treatment. In addition, almost all pigs exhibited normal firm feces in both trials and therefore there was no main effect in the fecal consistency score. Results suggest that partial substitution of the thermally processed corn for unprocessed corn of the milk product-corn-soy-based and medicated starter diet has no effect on growth performance or incidence of diarrhea in weanling pigs.

• Journal of Plant Biology
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• v.32 no.3
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• pp.137-144
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• 1989

In order to clarify the effect of the associative nitrogen fixing bacteria on the growth of corn(Zea mays L. Suwon19), we inoculated corn seedlings with Azospirillum amazonense Y1, a micro-aerobic and acid-tolerant nitrogen fixer, and analyzed the growth and dry matter production and changes of nitrogen and phosphorus quantity of the plant during the growing period. The inoculation of associative N-fixing bacgteria increased the growth of height, leaf area, dry weight and total nitrogen quantity of the plant by 15.4%, 65.4%, 33.7% and 38.0%, respectively, on the day of 56th after sowing. Especially the inoculation of A. amazonense Y1 showed two to three-fold accumulation of phosphorus in each organ of plant. The associative bacteria accelerated the growth of the under ground parts more than those of the upper ground parts of corn plant, and caused decrease in T/R ratios.

• Asian-Australasian Journal of Animal Sciences
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• v.2 no.3
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• pp.359-360
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• 1989

• Journal of Sericultural and Entomological Science
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• v.19 no.1
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• pp.15-18
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• 1977

This study carried out to know whether corn shank can be used as the crude fiber source for the larval growth or not, The results obtained from this study are summarized as follows: 1. It seems that there are no bad effects of the artificial diet containing corn shank on feeding of the newly hatched larva. 2. Author did not find any bad effects of the artificial diet containing corn shank on larval growth and cocoon qualifies. 3. In view of these results, it seems that the corn shank is suitable for use as the crude fiber source for the silkworm artificial diet.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.84-84
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• 2022

The limit of crop cultivation is moving northward due to the temperature rise by climate change. There is a problem with crop growth if early sowing is performed at a time when the temperature is low. It is difficult to secure crop productivity and cultivation stability due to the low temperature and short cultivation period. Therefore, this study was conducted to analyze the change in growth characteristics and yield of corn for grain when early sowing is performed in central region of South Korea. This experiment was conducted at experimental field of Suwon in 2021. Three varieties of corn for grain such as Kwangpyeongok, Sinhwangok, and Hwangdaok were sown at intervals of 5 days from 20 March to 15 April. The planting density at this time was sown with a row interval of 70 cm and a plant interval of 25 cm. Nitrogen, phosphoric acid, and potassium fertilizers were applied at 17.4 kg, 3.0 kg, and 6.9 kg per 10a, respectively. Phosphoric acid and potassium fertilizers were all applied before sowing and nitrogen fertilizer was applied 50% before sowing and 50% in the fifth leaf period. The corn growth characteristics and yield components were investigated. The seedling establishment rate by sowing date was in the range of 68.5~88.5%, and it showed a difference depending on the variety. The range of days from sowing to tassel and silk emergence by sowing date was 79.9~98.4 and 81.0~98.9 days, respectively. As the sowing date was delayed, the days from sowing to tassel and silk emergence decreased. The growth characteristics and yield of corn by sowing date are as follows. Plant height was the highest at 241.3 cm at the sowing on 25 March, and Stalk diameter was the thickest at 25.6 mm at the sowing on 31 March. The fresh weight per plant was the highest at 728 g at the sowing on 25 March, and the dry weight per plant was the highest at 185 g at the sowing on 31 March. Corn growth characteristics did not show a certain trend depending on the sowing date, and corn growth was more vigorous at the sowing on March 25 and 31 than the others. In the case of ear weight, it was the heaviest with 344 g at the sowing on 25 March, and filled ear length ratio showed a tendency to decrease as the sowing time was delayed. The weight of 100 grains and grain yield per 10a of maize were the highest at 36.0g and 878.7kg/10a, respectively at the sowing on 25 March. Although the growth and yield of corn for grain were good during early sowing in the central region of South Korea, it is necessary to investigate the limit temperature for early sowing of corn by examining the annual variation according to weather conditions.

• Journal of The Korean Society of Grassland and Forage Science
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• v.16 no.4
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• pp.299-306
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• 1996

This experiment was conducted from 1991 to 1993 at the forage experimental field, College of Agriculture and Life Sciences, SNU, Suweon to investigate the effects of previous crop residues on growth and yield of succeeding corn(2ea mays L.) and also to determine the best double cropping system necessary to maximize the total dry matter yield of winter forage crops plus corn for silage. In this experiment, treatments consisted of no crop as a control, late maturing Kodiak rye(Seca1e cereale L.), Bamapoli forage rape(Brassica napus Subsp. oleifera L.), G-sprinter oats(Avem sativa L.), Chief crimson clover(Trifolium incarnatum L.), Jackson Italian ryegrass(lo1ium rnultiJlorum L.), Vantage vetch(Vicia sativa L.) and early maturing Koolgrazer rye(Seca1e cereale L.). Corn leaf number and silking date were not significantly affected by previous crop residues, but the leaf number of corn following Italian ryegrass was reduced by 1.9 relative to no previous crop. The plant height and LA1 were significantly reduced during early development when corn followed Italian ryegrass and late maturing Kodiak rye (p<0.05). The dry matter and estimated TDN yields of corn were significantly reduced when corn followed Italian ryegrass and late maturing Kodiak rye. The yield reductions for corn following Italian ryegrass, late maturing Kodiak rye and early maturing Koolgrazer rye, relative to com when no previous crops were planted, were 34, 17 and 8%, respectively. Therefore, the reduction in corn growth and yield in this experiment could be explained by an allelopathic effect resulting from the Italian ryegrass and rye residues. The highest total dry matter yield of 30,509kg/ha was obtained from an early maturing rye-corn double cropping sequence in combination among the eight cropping systems.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.5
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• pp.560-564
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• 2011

Two feeding experiments were conducted to investigate the effects of dietary inclusion of genetically modified (GM) soybean and corn on the growth performance, feed utilization and body composition of juvenile abalone Haliotis discus hannai. Four isonitrogenous (31% crude protein) and isolipidic (6% crude lipid) diets (designated as nGM-soya, GM-soya, nGM-corn and GM-corn) were formulated to contain 20% non-GM (nGM) and GM soya and corn. Fifty juvenile abalone (initial body weight, 2.0 g) were distributed in each 50 L tank in a flow-through system. Each experimental diet was fed to duplicate groups of abalone to satiation once a day for 10 weeks. No effects of GM feedstuffs on survival were observed. Dietary inclusion of GM feedstuffs did not affect either growth performance or feed utilization of abalone. Body composition was not altered by the inclusion of GM feedstuffs. These results indicate that dietary inclusion of GM soybean and corn could have no effect on the growth performance and body composition of juvenile abalone. Further studies to investigate the effects of GM feedstuffs on transgenic fragment residues in ambient environments and in animals are necessary for the safe use of such ingredients in aquaculture.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.1
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• pp.28-31
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• 2005

To identify salt-tolerance characteristics of corn seedling was treated in solution of 0, 50 and 100 mM NaCl of hydroponic cultivation. In photosynthesis of corn seedling, there was no large difference between 50mM and 0 mM NaCl solution, however, in 100 mM NaCl solution, the tolerance gradually decreased to $76\%,\;49\%,\;and\;31\%$ after one day, four days, and seven days, respectively, in comparison to 0 mM NaCl solution. Osmotic potential of corn in seedling period was significantly decreased with increasing saline level, however, free proline content in the plant on the ground was significantly increased with increasing saline level and with the lapse of time. In terms of correlation among major characteristics, there was a highly significant positive difference between osmotic pressure potential and photosynthesis, However, highly negative correlation was found between osmotic pressure potential and free proline content. In addition, it was expected that young seedling of corn with saline tolerance may be utilized in the transplantation in salt-accumulated land. Based on above-shown result, in terms of saline tolerance of Chalok-2 variety, growth suppression was serious with 100mM NaCl solution. However, growth was expected that seedling growth would be favorable under 50 mM NaCl solution.

• Journal of The Korean Society of Grassland and Forage Science
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• v.43 no.3
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• pp.183-189
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• 2023

It is widely known that forage corn is one of the most important crops in the production of silage and green chops during the summer months. In this study, the characteristics and the productivity of Kwangpyeongok, AGR 41, and Nero IT corn cultivars were evaluated in the regions of Jeju and Cheonan, Korea between 2021 and 2022. In each year, different corn cultivars were sown in different parts of the country on April 7 in Jeju and May 3 in Cheonan. The yield of three cultivars, Kwangpyeongok, AGR 41, and Nero IT were measured at the yellow-ripening stage, including the leaves and stems (Stover) and corn grain. Kwangpyeongok stover and total dry matter (DM) yields were slightly higher in Cheonan than in Jeju over the past two years. The quantity of corn cultivated in all cultivated areas was similar. The average yield of AGR 41, corn quantity and total DM were slightly higher in Jeju than in Cheonan. In terms of stover yield, and total dry matter content of the Nero IT cultivar cultivated in Jeju had a slightly higher yield than the cultivar cultivated in Cheonan. Based on this study, all cultivars can show some variations but not too much in terms of growth productivity and distinct characteristics depending on their location. Overall, AGR 41, and Nero IT cultivars in Jeju exhibit slightly higher levels of productivity than the same cultivars in Cheonan.