• Asian-Australasian Journal of Animal Sciences
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• v.23 no.2
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• pp.240-245
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• 2010

The effects of controlled energy restriction and duration of pre-incubation egg holding on fertility, hatchability and hatch losses were evaluated in aged broiler breeders (64 wk). The energy (ME) required for maintenance, activity, growth and anticipated egg production was calculated and offered to a control group (283-471 kcal/kg) from 21-64 weeks of age. In three other groups, ME was quantitatively reduced either by 20% (SER; severe energy restriction) or 10% (MER; moderate energy restriction) and increased by10% (EEF; excess energy feeding) over the control group (CER; controlled energy restriction). Each diet was offered to 130 pullets in individual cages, and the quantity of ME increased with age. At the end of 64 weeks, fertile eggs were collected from each dietary group for 11 consecutive days and grouped under 4 holding periods based on the length of storage (2, 5, 8 or 11 d). The influence of energy regimes, egg holding intervals and their interaction was evaluated on fertility, hatch losses and hatchability. Broiler breeders maintained on SER regime (231-419 kcal/d) produced maximum number of eggs (993) followed by MER (819), CER (624) and EEF (438) during the 11-day period. The percent fertility and hatchability was significantly (p$\leq$0.05) higher in SER and MER groups compared to CER and EEF. However, energy regimes did not influence the loss in egg weight during pre-incubation storage, shell weight, shell thickness or hatch losses as dead germs and dead in shell. The improvement in hatchability in SER and MER groups appeared to be closely related to higher fertility and lower embryonic mortality. Holding of eggs for 11 days showed a linear loss in egg weight with the length of storage, but did not influence the fertility and hatch losses. The percent hatchability on eggs set was maximum when storage period was restricted to 5 days. The interaction between energy regimes and egg holding periods exhibited better hatchability results with SER regime when eggs were held for 5 days. Response to MER was not different from SER. It was obvious that energy restriction during production period had a positive influence on egg number, fertility and hatchability in aged breeders. At 64 weeks of age, holding of fertile eggs for 5 days prior to incubation was adequate for optimum hatchability in breeders.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.26 no.4
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• pp.345-354
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• 2000

TGF-${\beta}_1$ is a potent chemotactic factor for inflammatory cells and fibroblasts. It also stimulates the celluar source and components of extracellular matrix and the production of proteinase inhibitors. Collectively, these biologic activities lead to the accumulation and stabilization of the nascent matrix, which is vital to wound healing. The objective of this study is to investigate production of TGF-${\beta}_1$ in vitro fibroblast culture in the presence of Staphylococcus enterotoxin B(SEB) and/or lipopolysaccharide(LPS) and to elucidate the role of TGF-${\beta}_1$ which may be responsible for wound healing. The fibroblasts were originated from facial dermis and hypertrophic scar in 26 year-old male patient. In the presence of LPS($0.01{\mu}g$, $0.1{\mu}g$, $1.0{\mu}g$), SEB($0.01{\mu}g$, $0.1{\mu}g$, $1.0{\mu}g$) respectively, cells($5{\times}10^3ml$) were cultivated in vitro. At 1, 3, and 5 days after incubation, cells were counted. Also, cells($2.5{\times}10^5ml$) were cultivated in EMEM with LPS(0.01, 0.1 and $1.0{\mu}g$), SEB(0.01, 0.1 and $1.0{\mu}g$) respectively and LPS($0.1{\mu}g$) and SEB($0.1{\mu}g$) in combination for 24, 48, and 72 hours respectively. Culture supernatants were harvested at 1, 2, and 3 days after incubation period and triplicate culture supernatants were pooled and TGF-${\beta}_1$ was assayed in duplicate. The results were as follows. 1. In facial dermal fibroblast induced with SEB and LPS respectively or in combination, the suppression of cell proliferation occurred very significantly at 1 day after incubation, compared with the control. In SEB exposure, the production of TGF-${\beta}_1$ was decreased very significantly at 1 day after incubation, compared with the control. However, in LPS, SEB and LPS exposure, the production of TGF-${\beta}_1$ was increased very significantly at 1 day after incubation, compared with the control. 2. In hypertrophic scar fibroblast induced with SEB and LPS respectively or in combination, the suppression of cell proliferation did not occur at 1 day after incubation, compared with the control. In SEB and LPS exposure in combination, the production of TGF-${\beta}_1$ was increased very significantly at 1 day after incubation, compared with the control. However, the production of TGF-${\beta}_1$ did not occur in SEB and LPS exposure respectively. In conclusion, the concentration of bacterial toxins and the incubation period correlated with cell proliferation and production of TGF-${\beta}_1$ very significantly and both fibroblasts have different phenotype each other in this regard. This data suggest that the significant production of TGF-${\beta}_1$ may develope abnormal wound healing associated with tissue fibroproliferative disorder, such as hypertrophic scar and keloid formation.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.12
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• pp.1653-1658
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• 2000

Insulin-like growth factor-I (IGF-I) mRNA levels in the eyes, heart, liver and breast muscle removed from dwarf egg-type, normal egg-type and normal meat-type chicken embryos at 7, 14 and 20 days of incubation were measured. There was no influence of chicken strain on IGF-I gene expression in the eyes and liver. The IGF-I gene expression in eyes increased significantly along with the incubation period. In the liver, IGF-I gene expression at 20 days of incubation was significantly higher than that at 14 days of incubation. In the muscle, the lowest value for IGF-I gene expression was observed in meat-type chicken embryos. Regression analysis revealed that IGF-I gene expression was significantly correlated to the weights of the eyes and liver, but not the muscle. We conclude that there is little influence of strain on tissue IGF-I gene expression in chicken embryos during incubation but that tissue development in chicken embryos is nevertheless at least partly regulated by the change in IGF-I gene expression.

• Ocean and Polar Research
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• v.28 no.2
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• pp.201-207
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• 2006

We studied variation in clutch size, hatching, fledging and breeding success of the Black-tailed Gull (larus crassirostris) at Hongdo Island, which supported the largest breeding colony of the species, in South Korea in 1997 and 2000 to 2003. Cluck size was recorded in 1,388 nests and breeding success was estimated in 83 nests. Mean clutch size was 1.89 t 0.65. A total of 63.9% of the eggs hatched and 53.5% of the chicks survived until fledged. Breeding success was 34.2%. Causes of breeding failure were eggs missing (14.9%), rotten eggs (15.5%) and predation (2.4%) during the incubation period and chicks missing(35.8%), starvation (7.4%) and pecked chicks (3.2%) during the chick rearing period. In 2002, the main causes of breeding failure were eggs missing (17.2%) and rotten eggs (6.9%) during the incubation period and missing chicks (15.5%), starvation (3.5%) and pecked chicks (6.9%) during the chick rearing period. Most chick mortality occurred within three days after hatching.

• Korean Journal of Veterinary Service
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• v.22 no.4
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• pp.349-356
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• 1999

Type C botulism was broken out in cattle at Pochun country, Kyonggi in Korea. The main cause was on the feed of fermented food contaminated with Clostridium botulinum. It was supposed to be contaminated with C botulinum during producing the fermented food because of either using contaminated food residues or adding contaminated additive materials like sausage. One hundred and twenty out of 642 cattle in 11 farms showed typical botulism symptoms and 95 among them died. The incubation period was from 2 to 14 days and the average incubation period was 8 days. The mortality in this case was 18.3%.

• Communications for Statistical Applications and Methods
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• v.8 no.3
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• pp.815-822
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• 2001

The aim of this study is to estimate the seroconversion date of the human immunodeficiency virus(HIV) infection for the HIV infected patients in Korea. Data are collected from two cohorts. The first cohort is a group of "seroprevalent" patients who were seropositive and AIDS-free at entry. The other is a group of "seroincident" patients who were initially seronegative but later converted to HIV antibody-positive. The seroconversion dates of the seroincident cohort are available while those of the seroprevalent cohort are not. Estimation of seroconversion date is important because it can be used to calculate the incubation period of AIDS which is defined as the elapsed time between the HIV infection and the development of AIDS. In this paper, a Weibull regression model Is fitted for the seroincident cohort using information about the elapsed time since seroconversion and the CD4$^{+}$ cell count.The seroconversion dates for the seroprevalent cohort are imputed on the basis of the marker of maturity of HIV infection percent of CD4$^{+}$cell count.unt.

• Parasites, Hosts and Diseases
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• v.51 no.2
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• pp.213-218
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• 2013

Malaria is a parasitic infection caused by Plasmodium species. Most of the imported malaria in Korea are due to Plasmodium vivax and Plasmodium falciparum, and Plasmodium ovale infections are very rare. Here, we report a case of a 24-year-old American woman who acquired P. ovale while staying in Ghana, West Africa for 5 months in 2010. The patient was diagnosed with P. ovale malaria based on a Wright-Giemsa stained peripheral blood smear, Plasmodium genus-specific real-time PCR, Plasmodium species-specific nested PCR, and sequencing targeting 18S rRNA gene. The strain identified had a very long incubation period of 19-24 months. Blood donors who have malaria with a very long incubation period could be a potential danger for propagating malaria. Therefore, we should identify imported P. ovale infections not only by morphological findings but also by molecular methods for preventing propagation and appropriate treatment.

• The Korean Journal of Applied Statistics
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• v.22 no.3
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• pp.607-616
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• 2009

In many epidemiological studies, the occurrence times of the event of interest are right-censored or interval censored. In certain situations such as the AIDS data, however, the incubation period which is the time between HIV infection and the diagnosis of AIDS is usually doubly censored. In this paper, we impute the interval censored HIV infection time using three imputation methods. Mid imputation, conditional mean imputation and approximate Bayesian bootstrap are implemented to obtain right censored data, and then Gibbs sampler is used to estimate the coefficient factor of the incubation period. By using Bayesian approach, flexible modeling and the use of prior information is available. We applied both parametric and semi-parametric methods for estimating the effect of the covariate and compared the imputation results incorporating prior information for the covariate effects.

• Korean journal of applied entomology
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• v.24 no.3 s.64
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• pp.135-139
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• 1985

Influence of temperature, relative humidity, spore washing and spore drying on conidial germination of Alternaria porri(Ell.) Cif. was studied. Maximum conidial germination occurred at 100% relative humidity prevailing for 6 hours or more at $25^{\circ}C$. Conidial germination decreased with increase in number of spore washings. Drying of conidia for more than half an hour caused significant decrease in germination. In all the experiments, conidial germinatio increased with increase in incubation period.

• Analytical Science and Technology
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• v.26 no.6
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• pp.401-406
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• 2013

Oxygen($O_2$) consumption and carbon dioxide($CO_2$) excretion of a fertile chicken egg during incubation were measured by a gas mass spectrometer. A closed sample chamber was developed to collect gas samples during the 20 days of artificial incubation of both a fertile and an infertile egg. After leaving an egg in the sample chamber for an hour, using a gas-tight syringe, samples of 2 mL of gas were collected from the closed sample chamber and analyzed using a gas mass spectrometer in 2~4 day intervals. The $O_2$ consumption and $CO_2$ excretion of chicken embryos increased rapidly after 10 days from the starting point of incubation. After 20 days, 23 mL of $O_2$ was consumed and 16 mL of $CO_2$ was excreted per hour. Throughout the whole period of incubation, concentration of $O_2$ decreased 4.3 mol% and $CO_2$ increased only 3.1 mole%, i.e., the mole of consumed $O_2$ and the mole of excreted $CO_2$ were not the same. On the other hand, during the same period, concentration of $N_2$ increased about 1.3 mol% and the increased mole fraction of $N_2$ was comparable with the difference (1.2 mol%) between the mole fraction of consumed $O_2$ and excreted $CO_2$. Therefore, we can attribute the increase of $N_2$ mole% to the difference of mole fraction between consumed $O_2$ and excreted $CO_2$. In this study, through the analysis of gas, we could explain the respiration of a fertile chicken egg during incubation.