• Asian-Australasian Journal of Animal Sciences
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• 제32권11호
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• pp.1715-1724
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• 2019

Objective: As laying hens become aged, laying performance and egg quality are generally impaired. One of the practical methods to rejuvenate production and egg quality of aged laying hens with decreasing productivity is a forced molting. However, the changes in intestinal microbiota after forced molting of aged hens are not clearly known. The aim of the present study was to analyze the changes in excreta bacterial communities after forced molting of aged laying hens. Methods: A total of one hundred 66-wk-old Hy-Line Brown laying hens were induced to molt by a 2-d water removal and an 11-d fasting until egg production completely ceased. The excreta samples of 16 hens with similar body weight were collected before and immediately after molting. Excreta bacterial communities were analyzed by high-throughput sequencing of bacterial 16S rRNA genes. Results: Bacteroidetes, Firmicutes, and Proteobacteria were the three major bacterial phyla in pre-molting and immediate post-molting hens, accounting for more than 98.0%. Lactobacillus genus had relatively high abundance in both group, but decreased by molting (62.3% in premolting and 24.9% in post-molting hens). Moreover, pathogenic bacteria such as Enterococcus cecorum and Escherichia coli were more abundant in immediate post-molting hens than in pre-molting hens. Forced molting influenced the alpha diversity, with higher Chao1 (p = 0.012), phylogenetic diversity whole tree (p = 0.014), observed operational taxonomic unit indices (p = 0.006), and Simpson indices (p<0.001), which indicated that forced molting increased excreta bacterial richness of aged laying hens. Conclusion: This study improves the current knowledge of bacterial community alterations in the excreta by forced molting in aged laying hens, which can provide increasing opportunity to develop novel dietary and management skills for improving the gastrointestinal health of aged laying hens after molting.

• 한국동물위생학회지
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• 제44권3호
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• pp.141-148
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• 2021

The objective of this research was to evaluate the immune response to Salmonella Gallinarum experimentally infected layers fed with Guanosine 5'-monophosphate-chelated calcium and iron feed additives. Hy-Line brown, 34 week-olds layers were assigned to 3 groups; Group 1: basal diet feed, Group 2 (CaFe-GMP): basal diet feed mixed with chelated calcium and iron, and Group 3 (Fe-OCHT): basal diet feed mixed with chitosan for 4 weeks. There were challenged with 1.0×10⁸ CFU/mL of the cultured Salmonella Gallinarum (SG) by oral administration on 28th feeding days. After SG challenge, Flow cytometric profiles showed that the CD4+/CD8+ T lymphocyte activation of Group 2 was much higher than Group 1 and Group 3 (P<0.05). In addition, the levels of interleukin-2 (13.37 mg/dl) and interferon-γ (2.35 mg/dl) in Group 2 were higher than Group 1 and Group 2. Populations of Lactic acid bacteria (3.5×10¹⁰ CFU/g) from cecum was highest observed in group 2. Re-isolation of SG from cecum in group 2 (8×10⁵ CFU/g) was lower than group 1 (1.83×10¹⁰ CFU/g). The result of this study demonstrated that CaFe-GMP feed additive may be one of the potential candidates to control salmonellosis and functional feeds in layers.

• Journal of Animal Science and Technology
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• 제63권6호
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• pp.1275-1285
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• 2021

The objective of the present experiment was to investigate the effect of dietary palm kernel meal (PKM) and β-xylanase supplementation on productive performance, egg quality, fatty liver incidence, and excreta characteristics in laying hens. A total of 320 Hy-Line Brown laying hens (33 weeks of age) were allotted to 1 of 4 treatments with 8 replicates in a feeding trial. Each replicate consisted of 10 consecutive cages with 1 hen per cage. The corn-soybean meal-based control diet was prepared. Additional diet was prepared by including 10% of PKM in the control diet with a partial replacement of corn, soybean meal, and animal fat. In addition, 0.025% β-xylanase was supplemented at the expense of celite to those 2 diets to produce 4 treatment diets in a 2 × 2 factorial arrangement. All hens were provided the diet and water ad libitum for 8 weeks. Results indicated no significant interactions between inclusion of dietary PKM and β-xylanase for all measurements; therefore, the main effects were mainly discussed. Hens fed diets containing 10% PKM had greater (p < 0.05) feed intake and yolk color than those fed diets containing no PKM. However, dietary PKM did not influence fatty liver incidence and excreta characteristics. Dietary β-xylanase supplementation had no effects on all measurements, regardless of inclusion of PKM. In conclusion, PKM can be a potential feed ingredient for laying hens at the inclusion of 10% in the diet. It appears that dietary β-xylanase used in the current experiment has little effect on layer productivity, regardless of inclusion of 10% PKM in the diet.

• 한국육종학회지
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• 제41권4호
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• pp.429-436
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• 2009

We conducted a QTL analysis of grain quality traits using 117 $BC_3F_4$ and $BC_3F_5$ lines developed from a cross between Ilpumbyeo and Moroberekan. Genotypes of 117 $BC_3F_5$ lines were determined using 134 simple sequence repeat (SSR) markers. A linkage map constructed using 134 SSR markers was employed to characterize quantitative trait loci (QTL). The 117 $BC_3F_4$ and $BC_3F_5$ lines were evaluated for eleven grain quality traits in 2005 and 2006. A total of 18 QTLs were identified for eleven traits, and the phenotypic variance explained by each QTL ranged from 9.9% to 35.2%. Moroberekan alleles contributed positive effects in the Ilpumbyeo background at two QTL loci for 1,000 grain weight. Four QTLs, two for chalky rice and one each for 1,000 grain weight and head rice were consistently detected in two consecutive years indicating that these QTLs are stable. Clusters of QTLs were observed in three chromosome regions. One cluster harboring five QTLs including head rice and brown rice ratio near SSR markers RM190 and RM314 was detected on chromosome 6. Another cluster harboring grain weight and white belly was detected on chromosome 2. Increase in white belly at this locus might be due to the increase in grain weight due to the presence of the Moroberekan allele. The Moroberekan alleles at two QTL loci, gw3 and gw4 associated with increased grain weight might be useful in breeding programs to develop high-yielding cultivars.

• 한국육종학회지
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• 제43권3호
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• pp.196-200
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• 2011

'슈퍼자미'는 한국방송통신대학교 농학과에서 2009년도에 육성한 C3G 고함유 흑자색 품종으로 주요특성과 수량성을 요약하면 다음과 같다. 1. 중부평야지 평균 출수기는 8월 25일로 만생종이며, 간장은 75 cm 정도이고, 종피색이 흑자색인 유색메벼 품종이다. 2. 현미천립중은 26.2 g 정도이고, 장폭비는 1.87로 단원형이며, 종피는 흑자색으로 안토시아닌 주색소인 C3G 함량이 '흑진주벼'의 10배 수준으로 색택이 균일한 품종이다. 3. 중부평야지역 보통기 보비재배 2개소에서 평균 629.7 kg/10a 수준으로 '흑진주벼'의 162% 수준이다.

• Journal of Microbiology and Biotechnology
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• 제29권5호
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• pp.820-826
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• 2019

This study evaluated the anti-inflammatory potential of a grasshopper ketone (GK) isolated from the brown alga Sargassum fulvellum on lipopolysaccharide (LPS)-induced RAW 264.7 murine macrophage cell line. GK was isolated and purified from the n-hexane fraction and its structure was verified on the basis of NMR spectroscopic data. GK up to $100{\mu}g/ml$ is not cytotoxic to RAW 264.7, and is an effective inhibitor of LPS-induced NO production in RAW 264.7 cells. The production of pro-inflammatory cytokines, including IL-6, $IL-1{\beta}$, and $TNF-{\alpha}$ was found significantly reduced in $0.1-100{\mu}g/ml$ dose ranges of GK treatment (p < 0.05). We confirmed the dose-dependent and significant inhibition of iNOS and COX-2 proteins expression. In addition, it has been shown that GK induces anti-inflammatory effects by inhibiting MAPKs (ERK, JNK, and p38) and $NF-{\kappa}B$ p65 phosphorylation. Our results show that the anti-inflammatory properties of GK may be due to the inhibition of the $NF-{\kappa}B$ and MAPKs pathways, which are associated with the attenuation of cytokine secretion.

• Animal Bioscience
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• 제34권2호
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• pp.285-294
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• 2021

Objective: This study was conducted to investigate the supplementary effect of a phytogenic blend (SPA: a mixture containing fermented Schisandra chinensis pomace, fermented Pinus densiflora needle extract, and Allium tuberosum powder in the ratio of 2:2:1) on egg production, egg quality, blood constituents, and visceral organs in laying hens. Methods: A total of 135 Hy-line brown laying hens (48-wk-old) were randomly allocated to three dietary treatments with 5 replicates of 9 hens. The control group (CON) was fed a basal diet (no exogenous SPA addition) and the experimental groups were fed the basal diet containing SPA at the level of 0.1% and 0.3% for 6 weeks. Results: The feed intake was significantly improved in SPA supplemented groups as compared with the control (p<0.05). However, egg production, daily egg mass, and feed conversion ratio were not different among the dietary treatments (p>0.05). For egg quality traits, only Haugh unit (HU) was significantly improved in SPA (0.3%) (p<0.05) as compared with other groups. However, HU was not affected during 4-wk of storage at 18℃ among the dietary treatments (p>0.05). Furthermore, SPA supplementation did not affect the blood biochemical constituents except for the phosphate content, which was significantly higher in SPA groups than the CON group (p<0.05). There were no significant differences in visceral organ characteristics and immune indicators (immunoglobulin A [IgA], IgG, and IgM) in SPA or CON groups. Conclusion: This study suggested that the supplementation of SPA may have beneficial effects on feed intake and egg quality in laying hens.

• Animal Bioscience
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• 제34권7호
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• pp.1235-1242
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• 2021

Objective: The purpose of this study was to identify through infrared thermal imaging technology the facial surface temperature (FST) of laying hens in response to the variations in their thermal environment, and to identify the regional differences in FST to determine the most stable and reliable facial regions for monitoring of thermoregulatory status in chickens. Methods: Thirty Hy-Line Brown hens (25-week-old) were sequentially exposed to three different thermal conditions; optimal (OT, 22℃±2℃), low (LT, 10℃±4℃), and high temperature (HT, 30℃±2℃). The mean values of FST in five facial regions including around the eyes, earlobes, wattles, beak and nose, and comb were recorded through infrared thermography. The maximum FST (MFST) was also identified among the five face-selective regions, and its relationship with temperature-humidity index (THI) was established to identify the range of MFST in response to the variations in their thermal environment. Results: Hens exposed to OT condition at 15:00 displayed a higher temperature at wattles and around the eyes compared to other regions (p<0.001). However, under LT condition at 05:00 to 08:00, around the eyes surface temperature showed the highest value (p<0.01). In HT, wattles temperature tended to show the highest temperature over almost time intervals. Main distribution regions of MFST were wattles (63.3%) and around the eyes (16.7%) in OT, around the eyes (50%) in LT, and wattles (62.2%) and comb (18.3%) in HT. The regression equation between MFST and THI was estimated as MFST = 35.37+0.2383×THI (R² = 0.44; p<0.001). Conclusion: The FST and the frequency of MFST in each facial region of laying hens responded sensitively to the variations in the thermal environment. The findings of this experiment provide useful information about the effect of the thermal conditions on the specific facial regions, thus offering an opportunity to stress and welfare assessment in poultry research and industry.

• 한국가금학회지
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• 제47권4호
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• pp.255-265
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• 2020

This study was performed to evaluate the effects of available phosphorus (AP) levels with or without supplemental phytase on the performance, egg quality, and serum biochemical parameters of laying hens. A total of 540 laying hens (40-week-old) were housed in cages and assigned to 6 dietary treatments with 5 replicates each, for 20 weeks. The treatments consisted of 0.20%, 0.25%, and 0.30% AP diets with or without phytase supplementation. During the 20-week period, egg production was lowest in hens fed the 0.20% AP diet; however, phytase supplementation in the diet completely corrected the adverse effect (P<0.05). No consistent difference was observed in egg production between hens fed the 0.25% and 0.30% AP diets and those fed the 0.20% and 0.30% AP diets with phytase supplementation. Similarly, egg mass was lowest in the 0.20% AP diet-fed group, and no difference in egg mass was observed in the 0.25% and 0.30% AP diet as well as the phytase-supplemented diet groups; however, egg mass was improved in the phytase-supplemented diet groups(P<0.05). Egg quality traits did not differ with dietary treatments. Serum alkaline phosphatase level showed a linear decrease (P<0.05) in the phytase-treated groups with increasing AP levels; moreover, a numerically linear increase (P<0.05) in serum Ca and P levels was observed in the phytase-treated groups. The results of this study indicate that phytase supplementation in the diet of laying hens could increase egg production and may lead to greater mineral absorption.

• Animal Bioscience
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• 제35권2호
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• pp.299-307
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• 2022

Objective: The objective of this study was to determine the effects of different social ranking order (SRO) and the enrichments (perch and dust-bath) allocation (EA) on behavior of laying hens in furnished cages. Methods: Total experimental period was 4 weeks. There were 216 Hy-line brown layers beak-trimmed at 1 d of age and selected randomly at 14 weeks of age from a commercial farm, and randomly divided into 36 cages with 6 hens in each cage. High enrichments (perch and dust-bath) allocation (HEA) and low enrichments (perch and dust-bath) allocation (LEA) were provided. Video observations of behavior were obtained from the focal hens between 14 and 18 weeks of age and perching, dust-bathing and other general behaviors of the hens with different social orders were measured. Results: Perching behavior of high SRO hens (HSR) were significantly higher than that of medium SRO hens (MSR), and that of the MSR were significantly higher than that of low SRO hens (LSR) (p<0.01), except for lying on perch (p>0.05). The hens in the high EA cage (HEAC) showed more lying behavior on perch than those in the low EA cage (LEAC) (p<0.01). The different SRO and EA did not affect dust-bathing behavior except vertical wing-shaking behavior (p<0.05). The LEA did not affect general behaviors (p>0.05), except standing and preening behaviors (p<0.01 and p<0.05), of which the hens in the HEAC showed less standing (p<0.01) and more preening behavior than the hens in the LEAC. Conclusion: The SRO of laying hens has a significant effect on the perching behaviors, but SRO and EA have little effect on dust-bathing and general behaviors.