• Parasites, Hosts and Diseases
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• 제55권2호
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• pp.175-183
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• 2017

Codon usage bias (CUB) is a unique property of genomes and has contributed to the better understanding of the molecular features and the evolution processes of particular gene. In this study, genetic indices associated with CUB, including relative synonymous codon usage and effective numbers of codons, as well as the nucleotide composition, were investigated in the Clonorchis sinensis tyrosinase genes and their platyhelminth orthologs, which play an important role in the eggshell formation. The relative synonymous codon usage patterns substantially differed among tyrosinase genes examined. In a neutrality analysis, the correlation between $GC_{12}$ and $GC_3$ was statistically significant, and the regression line had a relatively gradual slope (0.218). NC-plot, i.e., $GC_3$ vs effective number of codons (ENC), showed that most of the tyrosinase genes were below the expected curve. The codon adaptation index (CAI) values of the platyhelminth tyrosinases had a narrow distribution between 0.685/0.714 and 0.797/0.837, and were negatively correlated with their ENC. Taken together, these results suggested that CUB in the tyrosinase genes seemed to be basically governed by selection pressures rather than mutational bias, although the latter factor provided an additional force in shaping CUB of the C. sinensis and Opisthorchis viverrini genes. It was also apparent that the equilibrium point between selection pressure and mutational bias is much more inclined to selection pressure in highly expressed C. sinensis genes, than in poorly expressed genes.

• 한국가금학회지
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• 제25권2호
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• pp.71-77
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• 1998

This study was investigated to study split diets on laying performance and eggshell quality with Hy-Line brown layers 43 weeks old for 12 weeks Layers fed a conventional diet and split diets were divided into morning and afternoon diet. The conventional diet contained 3.4 % Ca was given constant nutrients all day. Hens of the split diets fed morning diets contained 0.5 % Ca constantly and afternoon diets contained 5.9, 8.0, and 10.0 % Ca in T1to T3. Split diets were given morning diets from 04:00 to 15:00 and afternoon diets 15:00 to 21 :00 alternately. Egg production, egg weight, and egg mass were not significantly different among diets. Abnormal eggs decreased in T1 and T2, but no significantly differed(P>0.05). Feed intake decreased in all of split diets compared to control diets (P <0.05). So, feed conversion ratio also improved in split diets(P<0.05). ME and CP intake decreased in T2 and T3, and Ca intake increased in proportion to Ca content of diets(P<0.05). ME and CP requirements per kg eggs decreased in the split diets, and that of Ca increased. Although there were not different significantly, egg shell strength and thickness improved slightly in T2 at 12 week. Yolk color, haugh unit and yolk index were not different among diets. Therefore, we concluded that split diet feeding to layer could improve feed and economic efficiency with normal egg production.

• 한국가금학회지
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• 제22권4호
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• pp.193-202
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• 1995

This study was carried out to investigate the effects of diverse dietary Ca levels and to determine whether bone mineral metabolism is influenced by the arnount of dietary Ca when given a choice of diets containing various levels of Ca. Forty Hy-line brown laying hens housed in separate cages were fed self-selected Ca diets. Birds were allowed a 7-day adaptation period followed by an 8-day collection period. Feed and water were available for ad libitum consumption. Eggs and excreta were collected at 6-h intervals during the day for mineral analysis. The Ca contents in excreta and retained Ca in the body on egg forming day were proportional to the amount of daily Ca intake. The retained Ca in the body were 0.97 g in control and 1.24~1.74 g in self-selected groups, respectively. Daily Ca contents (%) in tibial cortex were not consistent with feeding time intervals. The Ca content in tibial medulla in control group was lower than those of self-selected feeding groups(P<.05). The medullary Ca content in all treatment groups increased from 10:00 to 16:00 in a day. Ca content in plasma was low between 10:00 and 16:00 and was high between 22:00 and 04:00 in the following day.

• Journal of Biosystems Engineering
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• 제27권4호
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• pp.293-300
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• 2002

Surface crack detection is an important aspect in the quality control process of egg markets. The acoustic vibration of an egg could be used as a critical factor in evaluating the eggshell quality. The mode shape indicates the egg vibration behavior at different locations with respect to the input impulse and provides important information for the optimum sensor location to obtain the desired acoustic measurements. Theoretical analysis and experimental measurements were conducted to determine the acoustic vibration modes in eggs. The resonant fiequencies of the first and second resonance mode of intact eggs were found to be distributed between 2kHz and 7kHz range. The measured mode shapes of an egg were similar to theoretical shapes of homogeneous, elastic spheres. An elliptical deformation at the equator ring of the egg was observed. The frequency peak of this mode was dominantly present in the frequency spectrum of an intact egg impacted at its sharp position. The mode shapes related to the first resonant frequency of an egg shelved that the optimum location for the measuring sensor was the 180 degrees position. A optimum location for the egg support was found to be the 90 degrees position having the smallest vibration magnitude.

• 한국축산식품학회지
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• 제36권1호
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• pp.100-108
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• 2016

Microbiological contamination of eggs should be prevented in the poultry industry, as poultry is one of the major reservoirs of human Salmonella. ClO₂ gas has been reported to be an effective disinfectant in various industry fields, particularly the food industry. The aims of this study were to evaluate the antimicrobial effect of chlorine dioxide gas on two strains of Salmonella inoculated onto eggshells under various experimental conditions including concentrations, contact time, humidity, and percentage organic matter. As a result, it was shown that chlorine dioxide gas under wet conditions was more effective in inactivating Salmonella Enteritidis and Salmonella Gallinarum compared to that under dry conditions independently of the presence of organic matter (yeast extract). Under wet conditions, a greater than 4 log reduction in bacterial populations was achieved after 30 min of exposure to ClO₂ each at 20 ppm, 40 ppm, and 80 ppm against S. Enteritidis; 40 ppm and 80 ppm against S. Gallinarum. These results suggest that chlorine dioxide gas is an effective agent for controlling Salmonella, the most prevalent contaminant in the egg industry.

• Journal of Periodontal and Implant Science
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• 제38권1호
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• pp.83-90
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• 2008

Purpose: This study investigated the osteoconductivity of natural calcium carbonate-derived bone substitutes, hen eggshell (ES), and compared with those of commercial bone substitutes. Materials and Methods: Osseous defects created in the rat calvaria were filled with particulated ES(ES-1), ES with calcium-deficient hydroxyapatite surface layer (ES-2), Biocoral(Inoteb, France), and Bio-Oss(Geistlich Pharma, Wolhusen, Switzerland). After 4 and 8 weeks of healing, histomorphometic analysis was performed to evaluate the amount of newly formed mineralized bone area (NB%). Results: Histologic and histomorphometric analysis showed new bone formation and direct bony contact with the grafted materials in all groups. At 4 weeks, Biocoral group showed greater NB% compared to Bio-Oss and ES-1 groups (P<0.05). At 8 weeks, Biocoral and ES-2 groups showed significantly greater NB% compared to Bio-Oss group (P<0.05). Conclusion: These results indicate that natural calcium carbonate-derived bone substitutes with microporous calcium-deficient hydroxyapatite surface layer may be an effective materials treating osseous defects.

• 한국가금학회:학술대회논문집
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• 한국가금학회 2003년도 제20차 정기총회 및 학술발표회
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• pp.119-120
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• 2003

The experiments were conducted to investigate the effects of supplementary feather meal(FM) and its digest on the taurine content and performance of laying hens. Feeding trial was conducted with 810 78-wk-old ISA-Brown layers for 5wk. The experiment consisted of nine dietary treatments ； T1 ; control(basal diet), T2；Tl + feather meal(FM) 6 ％ diet, T3；T2 + pyridoxin(21 mg/kg) supplemented diet, T4； T1 + H$_2$O$_2$treated FM 6%, T5； T4 + pyridoxin(21 mg/kg) supplemented diet, T6； T1 + cystine(0.25 ％) supplemented diet, T7； T6 + pyridoxin(21 mg/kg) supplemented diet, T8； T1 + synthetic taurine supplemented(0.25％) diet, T9； T1 + synthetic taurine supplemented(0.5 ％) diet. Diets were formulated to be iso-caloric and to meet NRC(1994) requirements of essential nutriente. Birds in treatments T3 showed significantly higher(P＜0.01) egg production, feed intake, feed conversion ratio, egg weight, haugh unit and eggshell strength than those fed other treatments. Supplementation of FM. H$_2$O$_2$treated FM and cystine with or without pyridoxin did not significantly affected taurine content of egg yolk. Only synthetic taurine supplemented diets(T8 and T9) linearly increased(P＜0.01) taurine content of egg yolk.

• Animal Bioscience
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• 제35권8호
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• pp.1109-1120
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• 2022

Antibiotics used to be supplemented to animal feeds as growth promoter and as an effective strategy to reduce the burden of pathogenic bacteria present in the gastro-intestinal tract. However, in-feed antibiotics also kill bacteria that may be beneficial to the animal. Secondly, unrestricted use of antibiotics enhanced the antibiotic resistance in pathogenic bacteria. To overcome above problems, scientists are taking a great deal of measures to develop alternatives of antibiotics. There is convincing evidence that probiotics could replace in-feed antibiotics in poultry production. Because they have beneficial effects on growth performance, meat quality, bone health and eggshell quality in poultry. Better immune responses, healthier intestinal microflora and morphology which help the birds to resist against disease attack were also identified with the supplementation of probiotics. Probiotics establish cross-feeding between different bacterial strains of gut ecosystem and reduce the blood cholesterol level via bile salt hydrolase activity. The action mode of probiotics was also updated according to recently published literatures, i.e antimicrobial substances generation or toxin reduction. This comprehensive review of probiotics is aimed to highlight the beneficial effects of probiotics as a potential alternative strategy to replace the antibiotics in poultry.

• Journal of Dairy Science and Biotechnology
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• 제40권4호
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• pp.173-181
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• 2022

Industrial-scale Ca-fortified Dangmyon was manufactured with added casein phosphopeptides (CPP) to increase Ca adsorption in the intestine. Very low P content in eggshell Ca (egg Ca) and Dangmyon could make it possible to indirectly measure CPP content in Dangmyon. Partitions of the whole P present in Dangmyon were made into sweet potato, egg Ca, and CPP. The CPP content was obtained by multiplying CPP per P by the amount of P partitioned into CPP. It was found that 88.46% of CPP was obtained. However, when milk Ca, which was much higher in P, was added to fortify Dangmyon with CPP, it was found that the CPP content was either under- or over-estimated. Care must be taken when a much higher content of P as a Ca source is selected using this method. It was discovered that the added Ca and CPP were retained after cooking at boiling temperature; therefore, Dangmyon could be an excellent Ca and CPP carrier for humans.

• 농업과학연구
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• 제49권4호
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• pp.857-869
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• 2022

Eggs are considered an excellent complete food because they contain many major energy sources, including protein. Eggs are one of the most widely consumed foods worldwide, and egg consumption is steadily increasing. Eggs are generally classified according to their quality and weight. Various characteristics of eggs must be considered for the design and effective utilization of equipment used for the transport, processing, packaging, and storage of eggs. In this study, egg surface area, volume, density, etc. were measured according to the grade of the egg. The values of several geometrical properties that were measured tended to increase with increasing egg grade. The smallest grade eggs had the lowest shell thickness and density. The electrical conductivity of the eggshell and its contents was measured with a self-made electrode and equipment. The egg shell showed properties similar to insulators, and as the thickness increased, the electrical conductivity tended to increase. The electrical conductivity of the egg yolk showed almost constant values under all conditions. The electrical conductivity of the egg white and mixture was particularly low at 0.1 kHz. Fouling and electrode corrosion occurred in a low frequency region due to the egg white. In this study, various geometric and electrical characteristics of eggs were measured, and based on this, factors that could serve as new indicators for egg processed production were analyzed and investigated.