Ji-Hwan Lee

Dr. Ji-Hwan Lee

orcid

Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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11 May 2021 in Animals
Verified
Journal Article
Open access
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HOHan Jin Oh
Han Jin Oh
YPYei-Ju Park
Yei-Ju Park
JCJae Hyoung Cho
Jae Hyoung Cho
MSMinho Song
Minho Song
BGBon-Hee Gu
Bon-Hee Gu
MKMyunghoo Kim
Myunghoo Kim
Twenty weaned piglets with initial body weight of 6.83 ± 0.33 kg (21 day of age, LYD) were randomly assigned to four treatments for a two-week feeding trial to determine the effects of different dietary zinc on nutrient digestibility, intestinal health, and microbiome of weaned piglets. The dietary treatments included a negative control (CON), standard ZnO (ZnO, 2500 ppm), zinc chelate with glycine (Chelate-ZnO, 200 ppm), and nanoparticle-sized ZnO (Nano-ZnO, 200 ppm). At 0 to 1 week, the diarrhea score was decreased in the CON group compared with the ZnO, Chelate-ZnO, and Nano-ZnO group. In overall period, the ZnO and Nano-ZnO groups exhibited improved diarrhea scores compared to the CON group. The apparent total tract digestibility of dry matter and gross energy was the lowest in the CON group after one week. Compared to the ZnO group, the chelate-ZnO group exhibited higher proportion of T-bet+ and FoxP3+ T cells and the nano-ZnO group had higher numbers of RORgt+ and GATA3+ T cells in the mesenteric lymph nodes. ZnO group increased IL-6 and IL-8 levels in the colon tissues and these positive effects were observed in both chelate ZnO and nano-ZnO groups with lower level. The 16S rRNA gene analysis showed that the relative abundance of Prevotella was higher in the ZnO-treated groups than in the CON group and that of Succinivibrio was the highest in the nano-ZnO group. The relative abundance of Lactobacillus increased in the ZnO group. In conclusion, low nano-ZnO levels have similar effects on nutrient digestibility, fecal microflora, and intestinal immune profiles in weaning pigs; thus, nano-ZnO could be used as a ZnO alternative for promoting ZnO utilization and intestinal immunity.

19 February 2017 in Journal of Animal Science and Technology
Verified
Journal Article
Open access
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SOS. Y. Oh
S. Y. Oh
WYWon Yun
Won Yun
JLJi-Hwan Lee
Ji-Hwan Lee
CLC. H. Lee
C. H. Lee
WKW. K. Kwak
W. K. Kwak
JCJinho Cho
Jinho Cho
Biofilms were the third-dimensional structure in the solid surface of bacteria. Bacterial biofilms were difficult to control by host defenses and antibiotic therapies. Escherichia coli (E. coli) and Salmonella were popular pathogenic bacteria that live in human and animal intestines. Essential oils are aromatic oily liquids from plant materials and well known for their antibacterial activities. This study was conducted to determine effect of essential oil on anti-biological biofilm formation of E. coli and Salmonella strains in in vitro experiment. Two kinds of bacterial strains were separated from 0.2 g pig feces. Bacterial strains were distributed in 24 plates per treatment and each plates as a replication. The sample was coated with a Bacterial biofilm formation was. Photographic result, Escherichia coli (E. coli) and Salmonella bacteria colony surface were thick smooth surface in control. However, colony surface in blended and single essential oil treatment has shown crack surface layer compared with colony surfaces in control. In conclusion, this study could confirm that essential oils have some interesting effect on anti-biofilm formation of E. coli and Salmonella strains from pig feces.

2 September 2022 in Journal of Animal Science and Biotechnology
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Journal Article
Open access
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SCSe Yeon Chang
Se Yeon Chang
MSMinho Song
Minho Song
JLJi-Hwan Lee
Ji-Hwan Lee
HOHan Jin Oh
Han Jin Oh
YKYong ju Kim
Yong ju Kim
JCJinho Cho
Jinho Cho
Background: This study was conducted to investigate the effects of each phytogenic feed additive (PFA; PFA1, bitter citrus extract; PFA2, a microencapsulated blend of thymol and carvacrol; PFA3, a mixture of bitter citrus extract, thymol, and carvacrol; PFA4, a premixture of grape seed, grape marc extract, green tea, and hops; PFA5, fenugreek seed powder) on the growth performance, nutrient digestibility, intestinal morphology, and immune response in weaned pigs infected withEscherichia coli(E. coli).Results: A total of 63 4-week-old weaned pigs were placed in individual metabolic cages and assigned to seven treatment groups. The seven treatments were as follows: 1) NC; basal diet withoutE. colichallenge, 2) PC; basal diet withE. colichallenge, 3) T1; PC + 0.04% PFA1, 4) T2; PC + 0.01% PFA2, 5) T3; PC + 0.10% PFA3, 6) T4; PC + 0.04% PFA4, 7) T5; PC + 0.10% PFA5. The experiments lasted in 21 d, including 7 d before and 14 d after the firstE. colichallenge. In theE. colichallenge treatments, all pigs were orally inoculated by dividing a total of 10 mL ofE. coliF18 for 3 consecutive days. The PFA-added groups significantly increased (P < 0.05) average daily gain and feed efficiency and decreased (P < 0.05) the fecal score at d 0 to 14 post-inoculation (PI). Tumor necrosis factor α was significantly lower (P < 0.05) in the PFA-added groups except for T1 in d 14 PI compared to the PC treatment. The T3 had a higher (P < 0.05) immunoglobulin G and immunoglobulin A concentration compared to the PC treatment at d 7 PI. Also, T3 showed significantly higher (P < 0.05) villus height:crypt depth and claudin 1 expression in ileal mucosa, and significantly down-regulated (P < 0.05) the expression of calprotectin compared to the PC treatment.Conclusions: Supplementation of PFA in weaned pigs challenged withE. colialleviated the negative effects ofE. coliand improved growth performance. Among them, the mixed additive of bitter citrus extract, thymol, and carvacrol showed the most effective results, improving immune response, intestinal morphology, and expression of tight junctions.

14 September 2022 in Journal of Animal Science and Biotechnology
Verified
Journal Article
Open access
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JLJi-Hwan Lee
Ji-Hwan Lee
BLByongkon Lee
Byongkon Lee
XRXavière Rousseau
Xavière Rousseau
GGGilson Alexandre Gomes
Gilson Alexandre Gomes
HOHan Jin Oh
Han Jin Oh
JCJinho Cho
Jinho Cho
Background: Two experiments were conducted to establish an optimal NE challenge model and evaluate the efficacy of stimbiotic (STB) supplementation in necrotic enteritis (NE) challenged broilers. In Exp. 1, a total of 120 Arbor Acres (AA) broilers (45.0 ± 0.21 g) were randomly assigned to 6 treatments in a 3 × 2 factorial arrangement. Vaccine treatments included non-challenge (0), × 10 the recommended dose (× 10) or × 20 the recommended dose (× 20) by the manufacturer. Clostridium perfringens (CP) treatments were non-challenge (No) or 3 mL of 2.2 × 107 CFU CP challenge (Yes). In Exp. 2, a total of 72 AA broilers (40.17 ± 0.27 g) were randomly assigned to 6 treatments in a 3 × 2 factorial arrangement. Dietary treatments included non-additive (CON), 100 mg/kg STB (STB) and 100 mg/kg STB on top of a typical commercial blend including an essential oil, probiotics, and enzyme (CB). Challenge treatments included non-NE challenge (No) and NE challenge (Yes) as established in Exp. 1. Results: In Exp. 1, CP and vaccine challenge decreased (P < 0.05) body weight (BW), body weight gain (BWG) and feed intake (FI), and increased (P < 0.05) the number of broilers with diarrhea and intestinal lesions. The oral administration of × 20 recommended dose of vaccines coupled with 3 mL of 2.2 × 107 CFU CP resulted in (P < 0.01) a significantly increased incidence of wet litter and intestinal lesions. Thus, this treatment was chosen as the challenge model for the successful inducement of NE in Exp. 2. In Exp. 2, the NE challenge negatively affected (P < 0.01) growth performance, ileal morphology, immunoglobulin contents in blood, caecal microbiota in the caecum, footpad dermatitis, intestinal lesion scores, tumour necrosis factor (TNF-α) and endotoxin in the serum compared with the non-NE challenged birds. The supplementation of STB and CB in diets enhanced (P < 0.05) growth performance, intestinal microbiota, and blood profiles by stimulating ileal morphology (VH and VH:CD) and propionate production in the cecum, and there were no differences in measured variables between STB and CB supplemented birds. Conclusion: Overall, these results indicate that STB supplementation was able to reduce the inflammatory response and improve the performance of NE challenged birds, and the supplementation of STB alone was as effective as a typical commercial blend containing a number of other additives.

23 November 2024 in Animals
Verified
Journal Article
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LJLee Jihyeon
Lee Jihyeon
YCYohan Choi
Yohan Choi
HLHan-sung Lee
Han-sung Lee
HPHyun Ju Park
Hyun Ju Park
JHJunseon Hong
Junseon Hong
HCHyun-chong Cho
Hyun-chong Cho
Effective livestock management has become essential owing to an aging workforce and the growth of large-scale farming operations in the agricultural industry. Conventional monitoring methods, primarily reliant on manual observation, are increasingly reaching their limits, necessitating the development of innovative automated solutions. This study developed a system, termed mixed-ELAN, for real-time sow and piglet behavior detection using an extended ELAN architecture with diverse kernel sizes. The standard convolution operations within the ELAN framework were replaced with MixConv using diverse kernel sizes to enhance feature learning capabilities. To ensure high reliability, a performance evaluation of all techniques was conducted using a k-fold cross-validation (k = 3). The proposed architecture was applied to YOLOv7 and YOLOv9, yielding improvements of 1.5% and 2%, with mean average precision scores of 0.805 and 0.796, respectively, compared with the original models. Both models demonstrated significant performance improvements in detecting behaviors critical for piglet growth and survival, such as crushing and lying down, highlighting the effectiveness of the proposed architecture. These advances highlight the potential of AI and computer vision in agriculture, as well as the system’s benefits for improving animal welfare and farm management efficiency. The proposed architecture enhances the real-time monitoring and understanding of livestock behavior, establishing improved benchmarks for smart farming technologies and enabling further innovation in livestock management.

13 July 2022 in Animals
Verified
Journal Article
Open access
PDF file
DSDong Cheol Song
Dong Cheol Song
JLJi-Hwan Lee
Ji-Hwan Lee
WKWooGi Kwak
WooGi Kwak
MSMinho Song
Minho Song
HOHan Jin Oh
Han Jin Oh
JCJinho Cho
Jinho Cho
The aim of this study was to investigate the effects of stimbiotic (STB), a xylanase and xylo-oligosaccharide complex. A total of 36 male weaned pigs with initial body weights of 8.49 ± 0.10 kg were used in a 3-week experiment. The experiment was conducted in a 2 × 3 factorial arrangement (six replicates/treatment) of treatments consisting of two levels of challenge (challenge and non-challenge) and three levels of STB (0, 0.5, and 1 g/kg diet). Supplementations STB 0.5 g/kg (STB5) and STB 1 g/kg (STB10) improved the G:F (p = 0.04) in piglets challenged with STEC. STB supplementation, which also decreased (p < 0.05) the white blood cells, neutrophils, lymphocytes, and expression levels of tumor necrosis factor-alpha and interleukin-6. Supplementations STB5 and STB10 improved (p < 0.01) the lymphocytes and neutrophils in piglets challenged with STEC on 14 dpi. Additionally, supplementations STB5 and STB10 improved (p < 0.01) the tumor necrosis factor-alpha in piglets challenged with STEC on 3 dpi. Supplementations STB5 and STB10 also improved the villus height-to-crypt depth ratio (p < 0.01) in piglets challenged with STEC. Supplementation with STB reduced (p < 0.05) the expression levels of calprotectin. In conclusion, STB could alleviate a decrease of the performance, immune response, and inflammatory response induced by the STEC challenge.