• Korean Journal of Veterinary Research
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• v.44 no.1
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• pp.105-111
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• 2004

A total of 301 Thoroughbred mares were investigated the characteristics of breeding in the local areas in Jeju during the period from February 2000 to July 2001. The pregnancy rate and foaling rate in 143 mares were 93.0%, 72.0%, respectively, and mean gestational length was 339.3 days in 2000. The pregnancy rate in 158 mares was 86.7% in 2001. Mature follicles were ovulated in right(46.0%), left(45.2%), and bilateral(7.8%) ovary. The incidence of multiple pregnancies in 158 mares between 15 days and 45 days after mating were 89.3%(single), 10.1%(twin), and 0.6%(triple). The incidence of EED was 13.3%. Also uterine cyst and fluid had an bad influence on mare's pregnancy. These results suggest that regular monitoring of the pregnancies and maintaining of good uterine condition improve the pregnancy rates and foaling rates during breeding season.

• Asian-Australasian Journal of Animal Sciences
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• v.4 no.3
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• pp.231-234
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• 1991

Transferrin polymorphisms and growth rate up to 12 weeks of age were observed in RIR. crossbreds and native chickens. $Tf^{BB}$ genotype was observed in all types of bird. $Tf^{BC}$ occurred only in crossbred and native chickens. Frequency of $Tf^B$ was the highest in all types. Mean body weights at 8- and 12- weeks of age were the highest in RIR ($292{\pm}37.77$ and $612{\pm}75.69g$ respectively) and the lowest in natives for $Tf^{BC}$ ($180{\pm}11.54$ and $308{\pm}4.94g$ respectively). The difference in 12 week body weigh t of crossbreds between $Tf^{BB}$ and $Tf^{BC}$ was found to be significant (p<0.05). The results indicate that crossbreds ($Tf^{BB}$) may be grown effectively upto 12 weeks of age under Bangladesh conditions.

• Journal of Ecology and Environment
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• v.34 no.4
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• pp.357-363
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• 2011

To examine factors affecting feeding efficiency of grey herons (Ardea cinerea), the foraging behavior was studied at a reservoir in Asan city, Chungcheongnam-do, South Korea during the breeding seasons (from April to July) of 2006 and 2007. Four factors (age of foraging birds, time of day, breeding stage, and microhabitat type) were analyzed. Adults were more efficient foragers than recently fledged juveniles, and they had a higher success rate than juveniles. About half of the adults caught large prey, whereas most juveniles caught only small prey. Adult grey herons had different feeding efficiency according to the breeding stage. Pecking and capture rates were high during the late period (fledging stage), and biomass intake rates were high during the early (incubating stage) and late periods. However, time of day had no significant effect on foraging activity of adult grey herons. Feeding activities of adult grey herons also showed significant variation among microhabitat types. Pecking and capture rates were higher in the submerged plants area, but capture success rate and biomass intake rate were not different according to microhabitat type.

• Korean Journal of Environment and Ecology
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• v.29 no.5
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• pp.681-692
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• 2015

It is well documented that physiological and nutritional condition of wintering birds is strongly related to migration success to breeding sites, and also breeding success. However, how abiotic factors during winter affect the migration and breeding successes still remains unclear. Thus, this study developed a dynamic-state-dependent model for wintering life-history to identify the potential impact on the life-history, success to breeding site and breeding success of wintering birds, which are related to temperature fluctuation, interspecific competition and human disturbance at the wintering sites. To find the best-fit-model, we referred to the existing research data on wintering ecology of Red-crowned cranes (Grus japonensis) in Cheolwon, Korea, which is well documented as a long-term wintering study. Our model predicted that the higher temperature fluctuation and a higher rate of human disturbance are negatively related to migration success to breeding sites and their fitness, ultimately breeding success via changing of proportion in resource allocation (for e. g., lower energy compensation or higher level of stress accumulation). Particularly, the rate of body mass compensation after arrival at wintering sites may be accelerated when there are less temperature fluctuations and a lower rate of human disturbance. In addition, the rate of interspecific competition sharing the wintering foraging sites is negatively related to the rate of body mass compensation. Consequently, we discussed the conservation strategies of wintering birds based on the outcomes of the model.

• Korean Journal of Veterinary Service
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• v.17 no.3
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• pp.167-173
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• 1994

This study were performed to distribution of dermatophytes isolated from pet dogs in Pusan area and pathogenicity of the isolates. During the period from March 1993. to April 1994, 201 pet dogs of house breeding were examined. The result of obtained were summarized as followes； 1. Isolation rate of dermatophytes were 4.7%(7/149) in no lesion and 23.1%(12/52) in lesion of dog's skin. 2. According to breeding conditions, isolation rate of dermatophytes were 1) 3.8% in no lesion and indoor breeding, 2) 16.7% in lesion and indoor breeding, 3) 13.5% no lesion and outdoor breeding, and 4) 37.5% in lesion and outdoor bleeding. 3. Among the 201 Pet dogs, 16 strains of M. cams(84.2%), 1 of M. gypseum(5.3%), and 2 of T. mentagrophytes (10.5%) were isolated. 4. For Pathogenicity test, one strain of each M. canis, M, gypseum, T. mentagrophytes isolated from skin lesions were inoculated to the skin of the posterior back of guinea pigs. All of dermatophytes tested were induced skin lesions. Among them, M. cams and T. mentagrophytes were more virulent than M. gypseum.

• Korean Journal of Ecology and Environment
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• v.52 no.4
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• pp.378-384
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• 2019

Red-eared slider, Trachemys scripta elegans, is one of the most famous species to disturb native ecosystems in the world. In South Korea, the species was imported as pet, and now it is found whole of the country. Recent, natural breeding and spreading of the turtle has been reported. In this paper, we investigated the environmental factors to affect the reproduction of T. s. elegans. We surveyed the distribution of the turtle in Jeju island, South Korea, between 2012 to 2017. We compared the land covers and climate of habitats from breeding sites and non-breeding sites. The species was found from 38 sites in Jeju island; 21 of breeding sites and 17 of non-breeding sites. The number of total and only adult turtles was significantly higher in breeding sites than non-breeding sites (P<0.05). In breeding site, the reproduction rate from the farmland was significantly higher than others(P<0.05). However, the rate of land covers was not significant in non-breeding site (P>0.05). The difference on the climate between breeding and non-breeding was not significant(P>0.05). Moreover, none of climate factors affected to reproduction of T. s. elegans(P>0.05). Our study showed that the land covers surrounding the habitats are more important than climate for reproduction of T. s. elegans in Jeju island. This result indicates investigating the habitat and surrounding is necessary for the control of reproduction and spreading of the introduced species.

• Korean Journal of Poultry Science
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• v.46 no.4
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• pp.271-277
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• 2019

In recent years, consumers have recognized the issue of and expressed concern over farm animal welfare. Therefore, worldwide, chicken farms are transitioning from traditional caged breeding systems to welfare-oriented breeding systems. In this study, we further analyzed and compared the prevalence and protection rate of various diseases by challenging chickens under conventional and welfare-oriented breeding conditions with low pathogenic avian influenza. Ten chickens were randomly selected from each farm (conventional and welfare) from which Mycoplasma gallisepticum (MG) and Mycoplasma synoviae (MS) were identified and isolated. Additionally, low pathogenic avian influenza (LPAI) were challenged to broilers from each farm and samples were collected from these chickens using oral and cloacal swabs to investigate viral shedding and titer. The results showed that Mycoplasma infection did not significantly differ between breeding systems. Initially, LPAI viral shedding and titer significantly differed between breeding systems post-challenge, but as the experiment progressed, there was ultimately no significant difference.

• Journal of Environmental Science International
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• v.30 no.2
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• pp.185-189
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• 2021

This study was conducted to determine and to standardize the time of emergence of Protaetia brevitarsis adults, through four breeding experiments, including one which selected the dominant individuals of Protaetia brevitarsis. The breeding experiments were divided into two groups with hibernating and non-hibernating Protaetia brevitarsis by placing 100, 150, 200, 250 and 300 Protaetia brevitarsis in each breeding box (50 cm × 35 cm × 15 cm) filled with 12 L of fermented sawdust. Breeding tests were with four replicates each for 3 months. The test period was classified into four stages: Exp. 1 (Sep 1, 2019 to Nov 30, 2019), Exp. 2 (Dec 1, 2019 to Feb 29, 2020), Exp. 3 (Mar 1, 2019 to May 31, 2020) and Exp. 4 (Jun 1, 2020 to Aug 31, 2020). The survey items included average dead number, average emergence number, average mortality, and average emergence rate. In Exp. 1 and 2, the changes in Protaetia brevitarsis adults were similar. In Tables 1 and 2, the allegorical changes of adult white-spotted flowers were similar. In addition, the average dead number, average emergence number, average mortality, and average emergence rate showed better results in the hibernation state than in both Exp. 1 and 2. Exp. 3 and 4 showed a pattern of change different from the results of Exp. 1 and 2 and these characteristics were superior in the hibernation states compared to the non-hibernation states. In conclusion, this result was found to be most appropriate as a standardization of the emergence time of 200 Protaetia brevitarsis treatments through four breeding experiments in the hibernating state.

• Korean Journal of Veterinary Research
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• v.32 no.1
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• pp.143-151
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• 1992

Sixty Four fresh and 142 frozen embryos of dairy cattle were transferred to synchronized dairy, beef or Korean Native Cattle nonsurgically at National Animal Breeding Institute from 1985 to 1990. The results obtained were as follows ; 1. The pregnancy rate of fresh embryos(39.1%) was higher than that of frozen embryos(32.4%) and average pregnancy rate was 34.5%. 2. The pregnancy rate of grade 1 embryos was higher than that of grade 2 embryos for both fresh(41.3% vs 33.3%) and frozen embryos(35.4% vs 25.6%). 3. The pregnancy rate according to development stage of fresh embryos was increased with maturity as 29.2%, 33.3%, 50.0% and 54.5% for morula, early blastocyst, blastocyst and expanded blastocyst, respectively. For frozen embryos, the pregnancy rate of blastocyst(44.4%) was higher than those of morula(31.3%) and early blastocyst(28.0%). 4. The pregnancy rate according go recipient-donor synchrony for fresh embryos was higher when the recipients exhibited estrus 1 day earlier than the donors(43.8%) than when the recipients exhibited estrus 1 day later than the donors(38.1%) or when the recipients and donors exhibited estrus at the same time(37.0%). For forzen embryos, the pregnancy rate was decreased when the recipients and donors exhibited estrus at the same time(37.9%), when the recipients exhibited estrus 1 day later than the donors(32.0%) and when the recipients exhibited estrus 1 day earlier than the donors(23.5%), in sequence. 5. The pregnancy rate of heifers was higher than that of cows for both fresh(50.5% vs 37.9%) and frozen embryos(39.7% vs 25.7%). 6. The pregnancy rate according to recipient breed for fresh embryos was higher in dairy cattle(42.1%) and beef cattle(40.%) than in Korean Native Cattle(33.3%). For frozen embryos, the pregnancy rate was decreased beef cattle(39.1%), dairy cattle(30.3%) and Korean Native Cattle(14.3%), in sequence. 7. The pregnancy rate according to equilibrium steps of glycerol and freezing rate was higher when transferred after 3-steps equilibrium and freezing by the rate of $0.3^{\circ}C$/min from $-6^{\circ}C$ to $-35^{\circ}C$ and $0.1^{\circ}C$/min to $-38^{\circ}C$(39.4%) than when transferred after 6-steps equilibrium and freezing by the rate of $0.5^{\circ}C/min$ from $-6^{\circ}C$ to $-30^{\circ}C$(30.3%).

• International Journal of Industrial Entomology and Biomaterials
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• v.7 no.1
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• pp.21-27
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• 2003

Manifestation of heterotic genetic interaction was studied in different hybrids made between multivoltine recurrent backcross (RBL)/congenic lines (Con. L) during unfavourable season when temperature and relative humidity are > $30^{\circ}C$ and 86%, respectively. A few number of silkworm race or strain or breed like Nistari (N ＋ p or Np) can sustain the temperature above 3$0^{\circ}C$ and RH above 86%. The present heterosis study screened a hybrid i.e., CB$_{5}$Lm5RBL1M$_{6}$DPC-LmE$^1$RBL and its reciprocal provided heterobeltiotic effect on survival by number and pupation rate at a magnitude of 20% (p < 0.01) and yield by weight of 10% (p < 0.01). Beside all the hybrids expressed heterosis over check - Nistari (N ＋ p) with better quality silk. Therefore, aforesaid hybrid may be useful for utilization at commercial level during adverse seasons of West Bengal.gal.