• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.35 no.3
• /
• pp.254-258
• /
• 1990

In order to investigate the effect of sowing dates on some agronomical characters and yield of corn in southern part of Korea. a field experiment was carried out at Gyeongnam Provincial Livestock Breeding Station in chinju. Single cross hybrid corn (cv. Suwon #19) was sown from April 13 to June 2 with five-day interval in 1984 and 1984. The relationship between herbage and grain yield and various meterological measurements was evaluated. As the sowing dates were delayed. the days from sowing to seedling emergence were shortened, as more closely affected by the soil temperature at seedling emergence. growth period and was dependent on precipitation and temperature during the growth period. Based on the relationship between herbege dry matter yield of corn and soil temperature at seedling emergence, the estimated critical sowing date for corn in the southern Korea was March 23${\pm}$3.6 days.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.13 no.2
• /
• pp.139-144
• /
• 1993

This experiment was carried out to determine the body weight gain, days required to be grown from 100 to 400kg body weight and nutrient intake of thirty growing Holstein heifers fed three different levels of nutrient (80, 100 and 120% of NRC requirement) by two different sources of roughage (corn silage and rice straw). The experiment was arranged as a completely random block design with 5 replications. The results obtained are summarized as follows: I. Average daily weight gain of heifers fed corn silage and rice straw was the highest at 200 and 250kg body weight, respectively. 2. As body weight increased, OM, CP and TON requirement increased-especially requirement of those nutrients being the highest at about 250- 300kg body weight. 3. At 250- 300kg body weight, correlations between body weight(X) and OM, CP and TON intake(l) requirement are the following. DMI = 8.0168X - 0.0209 (r=0.7986$^{**}$) CPI = 101428X - 0.0145 (r=0.5787$^{**}$) TDNI = 6.7620X - 0.3702 (r=0.6877$^{**}$)

• Asian-Australasian Journal of Animal Sciences
• /
• v.33 no.5
• /
• pp.753-762
• /
• 2020

Objective: The aim of the present study was to determine the effect of supplementing pasture-finished steers with corn silage on the expression level of the calpain system proteins and beef tenderization. Methods: Thirty Braford steers grazing on summer pasture were used for the study. For 120 days fifteen animals were supplemented with corn silage at 1% of body weight per head per day (Suppl) whereas the remaining 15 steers only received pasture (Contr). Carcass and meat traits were evaluated and compared between groups. Gene expression and activities of proteases (calpain 1 and calpain 2) and inhibitor (calpastatin) were measured using real-time polymerase chain reaction and casein zymography. Results: Carcass and meat traits were significantly different between feeding systems. Supplemented steers showed higher hot carcass weight (p<0.01), fat content (p = 0.02), and Warner-Bratzler shear force (p = 0.03). Furthermore, the control group showed higher protease:inhibitor ratios, at mRNA (p = 0.01) and protein levels (p<0.10). Warner-Bratzler shear force and mRNA calpains:calpastatin ratio were associated in both feeding systems (p<0.01). Conclusion: Based on the results obtained in the study, beef tenderness differences among finishing strategies could be modulated through differential expression of the calpain system proteins.

• Asian-Australasian Journal of Animal Sciences
• /
• v.27 no.9
• /
• pp.1285-1292
• /
• 2014

An in vitro experiment was conducted to evaluate the effects of Aspergillus oryzae culture (AOC) and 2-hydroxy-4-(methylthio)-butanoic acid (HMB) on rumen fermentation and microbial populations between different roughage sources. Two roughage sources (Chinese wild rye [CWR] vs corn silage [CS]) were assigned in a $2{\times}3$ factorial arrangement with HMB (0 or 15 mg) and AOC (0, 3, or 6 mg). Gas production (GP), microbial protein (MCP) and total volatile fatty acid (VFA) were increased in response to addition of HMB and AOC (p<0.01) for the two roughages. The HMB and AOC showed inconsistent effects on ammonia-N with different substrates. For CWR, neither HMB nor AOC had significant effect on molar proportion of individual VFA. For CS, acetate was increased (p = 0.02) and butyrate was decreased (p<0.01) by adding HMB and AOC. Increase of propionate was only occurred with AOC (p<0.01). Populations of protozoa ($p{\leq}0.03$) and fungi ($p{\leq}0.02$) of CWR were differently influenced by HMB and AOC. Percentages of F. succinogenes, R. albus, and R. flavefaciens (p<0.01) increased when AOC was added to CWR. For CS, HMB decreased the protozoa population (p = 0.01) and increased the populations of F. succinogenes and R. albus ($p{\leq}0.03$). Populations of fungi, F. succinogenes (p = 0.02) and R. flavefacien (p = 0.03) were increased by adding AOC. The HMB${\times}$AOC interactions were noted in MCP, fungi and R. flavefacien for CWR and GP, ammonia-N, MCP, total VFA, propionate, acetate/propionate (A/P) and R. albus for CS. It is inferred that addition of HMB and AOC could influence rumen fermentation of forages by increasing the number of rumen microbes.

• Asian-Australasian Journal of Animal Sciences
• /
• v.31 no.2
• /
• pp.198-207
• /
• 2018

Objective: This study investigated the association of yeast species with improved aerobic stability of total mixed ration (TMR) silages with prolonged ensiling, and clarified the characteristics of yeast species and their role during aerobic deterioration. Methods: Whole crop corn (WCC) silages and TMR silages formulated with WCC were ensiled for 7, 14, 28, and 56 d and used for an aerobic stability test. Predominant yeast species were isolated from different periods and identified by sequencing analyses of the 26S rRNA gene D1/D2 domain. Characteristics (assimilation and tolerance) of the yeast species and their role during aerobic deterioration were investigated. Results: In addition to species of Candida glabrata and Pichia kudriavzevii (P. kudriavzevii) previously isolated in WCC and TMR, Pichia manshurica (P. manshurica), Candida ethanolica (C. ethanolica), and Zygosaccharomyces bailii (Z. bailii) isolated at great frequency during deterioration, were capable of assimilating lactic or acetic acid and tolerant to acetic acid and might function more in deteriorating TMR silages at early fermentation (7 d and 14 d). With ensiling prolonged to 28 d, silages became more (p<0.01) stable when exposed to air, coinciding with the inhibition of yeast to below the detection limit. Species of P. manshurica that were predominant in deteriorating WCC silages were not detectable in TMR silages. In addition, the predominant yeast species of Z. bailii in deteriorating TMR silages at later fermentation (28 d and 56 d) were not observed in both WCC and WCC silages. Conclusion: The inhibition of yeasts, particularly P. kudriavzevii, probably account for the improved aerobic stability of TMR silages at later fermentation. Fewer species seemed to be involved in aerobic deterioration of silages at later fermentation and Z. bailii was most likely to initiate the aerobic deterioration of TMR silages at later fermentation. The use of WCC in TMR might not influence the predominant yeast species during aerobic deterioration of TMR silages.

• Asian-Australasian Journal of Animal Sciences
• /
• v.17 no.1
• /
• pp.53-62
• /
• 2004

The aim of this study was to predict the energy value and dynamic degradation of roughage in Taiwan using the $Daisy^{(R)}$. in vitro fermentation method to provide information on one of the very important nutrients for ration formulation. The second objective was to study the effects of Aspergillus oryzae (AFE) inclusion on nutrient utilization. Three ruminal fistulated dry dairy cows were used for rumen fluid and fifteen conventional forages used in dairy cattle were collected around this island. The degradability of these feedstuffs with and without AFE ($Amaferm^{(R)}$.) treatment was measured using the $Daisy^{(R)}$. in vitro method. The roughage energy values, including TDN and NEL, were calculated according to Robinson (2000). Results from the 30 h in vitro neutral detergent fiber (NDF) degradability and predicted energy evaluations showed that alfalfa (among the forages) contained the highest degradability and energy values, Bermuda straw having the lowest. Peanut vines and corn silage contained higher energy values and the lowest value found in Pangola and Napier grasses among the locally produced forages. Pangola and Napier grasses had lower values than most imported forages except Bermuda straw. Among the by-products, wheat middling contained the highest NDF degradability, while rice bran contained the richest energy value due to its high oil content. From the dynamic dry matter (DM), organic matter (OM), acid detergent fiber (ADF) and neutral detergent fiber (NDF) degradation, corn silage contained the highest effective degradation among the local forages; wheat middling (among the by-products) degraded the fastest in DM, OM, ADF and NDF and showed the highest effective degradability. AFE inclusion was inconsistent among the forages. Alfalfa hay showed significantly increased 30 h NDF degradability and energy values, Pangola hay, Napier grass and brewer's grains showed decreased degradability and energy values. AFE inclusion increased the DM, OM and NDF degradation rate in most forage, but only increased the DM degradation rate in sorghum distiller's grains, the OM degradation rate in bean curd pomace and the NDF and ADF degradation rates in soy pomace (among the by-products).

• Asian-Australasian Journal of Animal Sciences
• /
• v.22 no.3
• /
• pp.356-364
• /
• 2009

The current ruminant feeding models require parameterization of the digestion kinetics of carbohydrate fractions in feed ingredients to estimate the supply of nutrients from a ration. Using an automated gas production technique, statistically welldefined digestion rate of carbohydrate, including soluble carbohydrate, can be estimated in a relatively easy way. In this study, the gas production during in vitro fermentation was measured and recorded by an automated gas production system to investigate degradation kinetics of carbohydrate fractions of a wide range of ruminant feeds: corn silage, rice straw, corn, soybean hull, soybean meal, and cell mass from lysine production (CMLP). The gas production from un-fractionated, ethanol insoluble residue and neutral detergent insoluble residue of the feed samples were obtained. The gas profiles of carbohydrate fractions on the basis of the carbohydrate scheme of the Cornell Net Carbohydrate and Protein System (A, B1, B2, B3 and C) were generated using a subtraction approach. After the gas profiles were plotted with time, a curve was fitted with a single-pool exponential equation with a discrete lag to obtain kinetic parameters that can be used as inputs for modern nutritional models. The fractional degradation rate constants (Kd) of corn silage were 11.6, 25.7, 14.8 and 0.8%/h for un-fractioned, A, B1 and B2 fractions, respectively. The values were statistically well estimated, assessed by high t-value (>12.9). The Kd of carbohydrate fractions in rice straw were 4.8, 21.1, 5.7 and 0.5%/h for un-fractioned, A, B1 and B2 fractions, respectively. Although the Kd of B2 fraction was poorly defined with a t-value of 4.4, the Kd of the other fractions showed tvalues higher than 21.9. The un-fractioned corn showed the highest Kd (18.2%/h) among the feeds tested, and the Kd of A plus B1 fraction was 18.7%/h. Soybean hull had a Kd of 6.0, 29.0, 3.8 and 13.8%/h for un-fractioned, A, B1 and B2, respectively. The large Kd of fraction B2 indicated that NDF in soybean hull was easily degradable. The t-values were higher than 20 except for the B1 fraction (5.7). The estimated Kd of soybean meal was 9.6, 24.3, 5.0%/h for un-fractioned, A and B1 fractions, respectively. A small amount of gas (5.6 ml at 48 ho of incubation) was produced from fermentation of CMLP which contained little carbohydrate. In summary, the automated gas production system was satisfactory for the estimation of well defined (t-value >12) kinetic parameters and Kd of soluble carbohydrate fractions of various feedstuffs that supply mainly carbohydrate. The subtraction approach, however, should be applied with caution for some concentrates, especially those which contain a high level of crude protein since nitrogen-containing compounds can interfere with gas production.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.17 no.4
• /
• pp.315-322
• /
• 1997

Sixteen cultivars of corn(Zea mays L.) hybrids have been recommended as the government recommended corn hybrids since 1984, however, their forage performances have been mostly tested at two locations, such as Suweon and Sunghwan in the Middle parts of Korea. Therefore, the objective of this experiment was to retest the agronomic characteristics and yield of eleven of sixteen government recommended corn hybrids at five scattered locations, such as Icheon, Suweon, Sunghwan, Keonpan and Kwangju in 1993 and 1995 with the intention of improving recommendations to dairy farmers. Among the corn hybrids tested, 'Suweon 19' was susceptible to foliar diseases and poor stay green at all locations in 1993 and 1995. Generally, all hybrids have less lodging and infection rate of rice black streaked dwarf virus(RBSDV) varied by location but mostly not exceed 10%. Infection rate at Sunghwan and Kwangju among locations was the highest as 13.5 and 15.3% respectively. Among the corn hybrids tested, 'Suweon 19' was the highest RBSDV infection rate, but that of 'Kwanganok' and '3282' was lower than other hybrids. At all locations, '3352' and '3394' were the earliest in growth stage, but 'Kwanganok', '3282', 'DK729', 'G4624' and 'DK713' were the latest among the corn hybrids. Ear percentage in total DM of '3352', '3394' and 'G4624' was higher than other hybrids, but that of 'DK713' was the lowest among the corn hybrids. '3352' and '3394' showed the most suitable DM content for silage production at harvest. Among the corn hybrids tested, 'Suweon 19' and '3282' were the lowest DM yield at all locations in 1993 and 1995, but the highest DM yield varied by location. At Icheon, '3144W' and 'G4743', at Suweon, '3352' and '3144W, at Sunghwan, 'DK729' and '3144W', at Keongsan, '3352' and 'DK729', and at Kwangju, '3352' and 'DK689' were the highest DM yield in 1993 and 1995, respectively. Then, '3394' was higher than other hybrids at all locations in 1995. The government recommended corn hybrids tested were generally adapted across the country. However, in forage production situations where wrn should be harvested before the rainy season in late summer, earlymedium maturing corn hybrids, '3352' and '3394' might be preferred.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.11 no.2
• /
• pp.129-136
• /
• 1991

Dry matter productivity at silage stage of two corn hybrids varying resistance to rice blackstreaked dwarf virus(RBSDV) and two sorghum hybrids varying growth duration was evaluated at six planting dates (Apr. 1, Apr. 15, Apr. 29, May 13, May 27, and June 10) in Kyongsan where RBSDV is prevalent.Corn was harvested 38-40 days after silking. For sorghum 1st-cut was made 19-22 days after heading and some regrowth (2nd-cut) on October 13. 1. Percent stand of both corn hybrids was over 91% at all planting dates, but that of sorghum ranged 37.2-80.3% depending on hybrids and planting dates. 2. The number of days from planting to emergence decreased as planting date delayed in both crops. The number of days from emergence to silking of both corn hybrids and a sorghum hybrid(P 956) decreased as planting date delayed, but that of the other sorghum hybrid(P 931) increased significantly after May 13 planting. 3. RBSDV infection rate of corn hybrids was highest at April 1 planting (Kwanganok 24.896, Jinjuok 63.0%) and decreased up to April 29 planting and then increased as planting date delayed. Sorghum was not infected by RBSDV at all. 4. EarfTotal dry matter ratio of corn ranged 30.6-47.9% and that of sorghum 3.1-30.7% depending on hybrids and planting dates. All the hybrids developed grain normally at all planting dates except a sorghum hybrid (P 931) which developed few grains after May 13 planting. 5. Crude (C) protein and C. fat contents were similar among all treatments. C. fiber content of P 931 was higher than that of both corn hybrids and P 956, but nitrogen free extract (NFE) was lower. C. fiber and NFE of both corn hybrids and 1st-cut sorghum were similar among the planting dates, but C. fiber and NFE of 2nd-cut of sorghum decreased and C. protein increased as planting date delayed due to plants were younger. 6. Dry matter (DM) yield of all hybrids decreased as planting date delayed except Jinjuok of which yield was highest at April 29 planting. DM yield of corn was similar to 1st-cut sorghum, but lower than total DM yield of sorghum at April 1 and 15 plantings where regrowth yield was high.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.65 no.4
• /
• pp.416-425
• /
• 2020

This study evaluated the productivity of early maturity silage corns during continuous monocropping and the possibility of expanding forage production. Continuous monocropping of three silage corns, such as Kwangpyeongok (medium maturity), Sinhwangok (early maturity), and Sinhwangok2 (early maturity) was planted twice, in April and July from 2018 to 2019 at Suwon. The number of days from the sowing date to the silking date was 78 for the preceding crop and 52 for the succeeding crop. The number of days from the silking date to the harvesting date was 26 for the preceding crop and 46 for the succeeding crop. The sums of the temperature from the sowing date to the silking date were 1,512℃ for the preceding crop, 1,246℃ for the succeeding crop. The sums of the temperature from the sowing date to the harvesting date were 2,198℃ for the preceding crop and 1,951℃ for the succeeding crop. The dry matter yield of the preceding crop (1,637 kg/10a) was similar to that of the succeeding crop (1,565 kg/10a). The dry matter yields of Sinhwangok2 (1,673 kg/10a), Sinhwangok (1,660 kg/10a) and Kwangpyeongok (1,579 kg/10a) were similar to those of the preceding crop. The dry matter yields of Sinhwangok (1,669 kg/10a) and Kwangpyeongok (1,651 kg/10a) were similar to those of the succeeding crop and Sinhwangok2 (1,374 kg/10a) was the lowest among the three corn varieties. The total digestible nutrients (TDN) yield of the preceding crop (1,135 kg/10a) was similar to that of the succeeding crop (1,037 kg/10a). The TDN yields of Sinhwangok2 (1,183 kg/10a), Sinhwangok (1,158 kg/10a), and Kwangpyeongok (1,063 kg/10a) were similar to those of the preceding crop. The TDN yields of Sinhwangok (1,150 kg/10a) and Kwangpyeongok (1,100 kg/10a) were similar for the succeeding crop and Sinhwangok2 (970 kg/10a) was the lowest among the three corn varieties. The total dry matter yields of Sinhwangok (3,329 kg/10a) and Kwangpyeongok (3,230 kg/10a) were similar, but Sinhwangok2 (3,047 kg/10a) was the lowest among the three corn varieties. The total TDN yields of Sinhwangok (2,307 kg/10a), Kwangpyeongok (2,162 kg/10a), and Sinhwangok2 (2,152 kg/10a) were similar. It was concluded that Sinhwangok and Sinhwangok2 have high TDN yields as well as early maturity, and therefore are advantageous for direct continuous monocropping.