• Korean journal of applied entomology
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• v.43 no.3 s.136
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• pp.195-200
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• 2004

The occurrence pattern and bionomics of Selatosomus puncticollis (Motschulsky) were surveyed in three net house (6$\times$70m) in the field and in a laboratory ($20^{\circ}C$, RH$75\%$, L16/DB). Emergence of hibernated adults of S. puncricollis started from early May, reached peak at early June and diminished in late June. Occurrence rate to total number was $42.1\%$ in early June and $31.7\%$ in late May, when most of hibernated adults emerged at these periods. Adults started to oviposit from mid June, and eggs hatched from early July Larvae turned into pupae from mid July and emerged to adults from mid August. Egg-period was 23 days and pupal period was 21 days. It is estimated that preovipositional period and larval period were approximately 10 months and 30 months, respectively. Wireworms were distributed at the soil depth of 10-5 cm, $56.8\%$ in 1997 and $45.8\%$ in 1998. To establish bait techniques to attract wireworms in the soil, six baits: pieces of potato, carrot, and sweet potato, wheat grains, corns, and flour dough wrapped with gauze, were buried at 15 cm of soil depth, and collected after 5 and 10 days. The numbers of wireworms attracted by potato pieces, wheat grains and sweet potato pieces after 10 days were 1.8, 1.6, and 1.4/bait, respectively. Therefore, burying potato pieces at 15 cm of soil depth and collected after 10 days could be recommended as a wireworm baiting technique.

• Korean Journal of Agricultural Science
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• v.35 no.1
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• pp.101-118
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• 2008

This paper reviews the present situation of Triticale cultivation and examines the potentiality of contribution to livestock as well as poultry sector in Bangladesh Agriculture. Triticale is a human-made cross between rye and durum wheat that has the ability to produce quality green fodder, and then re-grow after first and second cutting to produce grain. In Bangladesh, it is a non-traditional cereal that grows well during the cool and dry Rabi season (November-March) when fodder and feed scarcity is a major limiting factor for ruminant livestock. In Bangladesh Triticale was started to grow in the late Ninety's. The scientists of Bangladesh Agricultural Research Institute (BARI) were first introduced triticale in Bangladesh. Still now the situation of Triticale is grown as fooder and feed in Bangladesh within the scientists under trial. High quality grass fodder was obtained by cutting green triticale plants twice, at 35 and 50 days after seeding, while later the ratooning tillers produced grain to a yield of 1.1-2.4 t/ha of grain for poultry feed or human food. Triticale straw was twice as nutritious as rice or wheat straw and its grain contained more protein than other cereals. Researchers and farmers have also successfully made triticale hay and silage from a mixture of triticale green cuttings, rice straw and molasses. A feeding trial at Bangladesh Livestock Research Institute(BLRI), Savar station showed a large(46%) increase in cow live weight gain and a 36% increase in milk yield (but no change in milk quality or dry matter intake) in cows fed triticale silage compared with those fed rice straw over a period of nine weeks. In another feeding trial, it was found that triticale grain was a good replacement for wheat in the feed blend for chickens in Bangladesh. So it will be a good chance to alive our livestock as well as poultry sector if triticale enters to our existing cropping system as fodder cum grain. The challenge in Bangladesh is to identify fodder technologies that match existing small-scale farmer cropping patterns without needing major inputs or increasing risks. Preliminary field experiments revealed that triticale is a crop with good potential to produce quality fodder and grain for small scale farmers in Bangladesh.

• Journal of Aquaculture
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• v.20 no.4
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• pp.278-288
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• 2007

Shrimp culture in Korea had been rapidly developed during 1990's and the production of farmed shrimp reached 3,268 mt from 2,605 ha in 2001. However the shrimp production decreased to 2,368 mt in 2004 because of the mass mortality due to outbreak of white spot syndrome virus (WSSV). WSSV which is one of the most serious threats associated with cultured shrimp around the world has given the economic damages to shrimp culture industry every year since it was found from the shrimp ponds in the west coast of the South Korea in 1993. Various polyculture technologies of shrimp with shellfish, finfish or seaweeds have been implemented to reduce economic damages by mass mortalities of shrimp. Among them, the polyculture of shrimp with carnivorous fish can suppress or delay the viral outbreak of shrimp ponds because the fish may selectively eat the moribund shrimps infected by virus. To determine the selective predatory effect of river puffer Takifugu obscures on WSSV infected shrimp, postlarvae of Litopenaeus vannamei and Fenneropenaeus chinensis. One-year old river puffers were stocked to four earthen ponds of $1,616-1,848\;m^2$ in surface area as followings: polyculture LvP, L. vannamei ($43.4/m^2$)+puffer ($0.22/m^2$); control Lv, L. vannamei ($46.9/m^2$); polyculture FcP, F. chinensis ($30.3/m^2$)+puffer ($0.25/m^2$); control Fc, F. chinensis ($24.6/m^2$). Ponds of control Fc and polyculture FcP had mass mortalities by WSSV outbreak on the $51^{st}$ and $57^{th}$ days of culture respectively. The shrimps of polyculture LvP and control Lv were harvested on the $95^{th}\;day$. Shrimp survival rates of polyculture LvP and control Lv were 32.4% and 18.2% respectively and shrimp productivity of polyculture LvP was 69.2% higher than that of control Lv. Concentration of nutrients (TAN, $NO_2-N$, $NO_3-N$) was maintained within optimal ranges for shrimp growth although that of polyculture ponds showed at least two times higher than that of control ponds. The results suggest that polyculture of L. vannamei with river puffer is higher than monoculture in survival rate and productivity. In addition, F. chinensis should be carefully cultured because this species shows much higher susceptibility to WSSV than L. vannamei.

• The Korean Journal of Malacology
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• v.31 no.2
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• pp.83-92
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• 2015

The effect of different intermediated rearing method by expanding the attached floor space in order to highly density culture on the growth characteristics and survival rate of the juvenile abalone, Haliotis discus hannai, were investigated in land-based tanks. The intermediated culture methods was determined thru the shelter counts and layer for 10 month with two replicates : the single layer shelter (SLS), the double layer shelter (DLS), the triple layer shelter (TLS) and the single layer shelter under net cage (SLSNC). In addition, the culture on shallow race way tank had to set up as culture of the ditch raceway tank (CDRT) and the floor race way tank (CFRT). In the growth performance of reared abalone (initial mean shell length $54.18{\pm}7.39mm$ and weight $1.93{\pm}0.14g$) at experimental tanks, that the absolute growth rate (ARG), daily growth rate (DGR) and specific growth rate (SGR) to the shell length and shell breadth was not significant at each experimental tanks except SLSNC. As well as too, weight gain (WG), daily weight gain (DWG) and specific weight gain (SWG) to weight was not significant at each experimental tanks except SLSNC, too. Survival rates of CDRT and CFRT was lower than those of different experimental tanks (P < 0.05). Therefore, these results is showed that high density different intermediated rearing method by expanding the attached floor space for juvenile H. discus hannai was not have difference as growth performance and survival rate both one layer shelter and multi layer shelter. Also, it is considered that shallow race way tank was not useful rearing for the juvenile intermediate culture of H. discus hannai in land based.

• Korean Journal of Poultry Science
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• v.39 no.4
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• pp.305-310
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• 2012

This work was carried out to investigate performance and carcass yield of large-type broilers at different stocking densities. Treatments were T1 (9.1 birds/$m^2$), T2 (10.3 birds/$m^2$) and T3 (11.5 birds/$m^2$) by the stocking density. Four hundred eight 1-day-old Arbor Acre broiler chicks were used for six weeks (starter, 0~1 wks; earlier, 1~3 wks; finisher, 3~6 wks) and divided into 3 treatments (4 replications/treatment, 30, 34 or 38 birds/replication). Research indexes were rearing viability ratio, body weight, body weight gain, feed intake, feed conversion ratio, production efficiency factor and carcass ratio. Rearing viability ratio (%) was 89% or more for all treatments and there was no significant difference on weekly rearing viability ratio (%). Body weight of T2 was the greatest and that of T3 was the lowest at 1 weeks old (P<0.05). Body weight gain of T2 was the greatest and that of T3 was the lowest at 0~1 weeks old (P<0.05). However, body weight gain of T3 was the greatest and that of T1 was the lowest at 1~2 weeks old (P<0.05). Body weight gain of T2 was the greatest as 3,031 g among treatments at 0~6 weeks old (P<0.05). Feed intakes of T1, T2 and T3 were 1,417 g, 1,265 g and 1,355 g, respectively, and that of T1 was the greatest among treatments (P<0.05). There was no significant difference on body weight, body weight gain and feed intake. Feed conversion ratio of T1 was the greatest among treatments at 1~2 wks, 3~4 wks and 0~6 wks old (P<0.05). Production efficiency factors of T1, T2 and T3 were 363.5, 388.3 and 358.3, respectively, and there was no significant difference among treatments. Wing meat ratio of T1 was the higher compared to other treatments at the age of 4 wk (P<0.05). There was no significant difference on carcass ratio and partial meat ratio among treatments. Neck meat ratio of T2 was the lowest among treatments (P<0.05). This result may provide the standard data of different stocking densities for large-type broiler and the further research is needed.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.5
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• pp.500-507
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• 2016

This study was undertaken to improve the survival and early life growth rates of cold-water fish by culturing rotifer (Brachionus plicatilis) with low-temperature tolerance. The enrichment experiment was carried out at different temperatures and over different time intervals. Cultivation of the rotifer at low temperatures was repeated, with the selected and cultured as the water temperature was gradually lowered from $20^{\circ}C$ to $10^{\circ}C$. Enrichment of the rotifer was completed using A, S, SCV and SCP. Enrichment was carried out after 6, 12 and 24 hours at three different temperatures (10, 15 and $20^{\circ}C$). In the growth experiments, the rotifer increased to approximately triple their original size, from $350{\pm}7.9ind./ml$ to $1,064{\pm}5.7ind./ml$ at $10^{\circ}C$ over 50 days. The fatty acid composition of the four enrichment materials was species-specific, with the highest ratios belonging to eicosapentaenoic acid (EPA, C20:5n-3) and docosahezaenoic acid (DHA, C22:6n-3) in SCP. The fatty acid composition of the rotifers was affected by the enrichment materials. The EPA (% of total fatty acid) was more than 2 % in SCP, which showed a higher ratio than the other enrichment materials. DHA was higher in S reaching 12.40 % at $15^{\circ}C$ for 24 hours. The highest levels of EPA (3.09 %) and DHA (11.65 %) were obtained after the rotifers were enriched with S at $20^{\circ}C$ for 12hours.

• Korean Journal of Poultry Science
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• v.50 no.1
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• pp.41-50
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• 2023

Over the last decade, avian influenza (AI) has been considered an emerging disease that would become the next pandemic, particularly in countries like South Korea, with continuous animal outbreaks. In this situation, risk assessment is highly needed to prevent and prepare for human infection with AI. Thus, we developed the risk assessment matrix for a high-risk area of human infection with AI in South Korea based on the notion that risk is the multiplication of hazards with vulnerability. This matrix consisted of highly pathogenic avian influenza (HPAI) in poultry farms and the number of poultry-associated production facilities assumed as hazards of avian influenza and vulnerability, respectively. The average number of HPAI in poultry farms at the 229-municipal level as the hazard axis of the matrix was predicted using a negative binomial regression with nationwide outbreaks data from 2003 to 2018. The two components of the matrix were classified into five groups using the K-means clustering algorithm and multiplied, consequently producing the area-specific risk level of human infection. As a result, Naju-si, Jeongeup-si, and Namwon-si were categorized as high-risk areas for human infection with AI. These findings would contribute to designing the policies for human infection to minimize socio-economic damages.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.3
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• pp.380-385
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• 1998

This study evaluated the possible utilization and the replacing range of animal by-product mixture (ABPM) as a dietary fish meal replacer in growing common carp (Cyprinus carpio). ABPM is a mixture of leather meal, meat and bone meal, blood meal and squid liver powder at a specific weight based ratio. Five different diets were formulated on isonitrogenous and isocaloric basis of $40\%$ crude protein and 15.3 KJ/g diet in which white fish meal (WFM) protein was substituted with the ABPM Protein as follows: diet 1, $100\%$ WFM ($0\%$ ABPM, control); diet 2, $75\%$ WFM+$25\%$ ABPM ($25\%$ ABPM); diet $3,\;50\%$ WFM+$50\%$ ABPM ($50\%$ ABPM); diet 4 $25\%$ WFM+$75\%$ ABPM ($75\%$ ABPM); diet $5.0\%$ WFM+$100\%$ ABPM ($100\%$ ABPM). As the dietary protein sources, each diet contained $34.7\%$ of animal protein supplied by white fish meal and/or ABPM and $65.3\%$ of plant protein. After one week of conditioning period, fish averaging 10 g were randomly assigned to each diet treatment as triplicate groups and fed one of the experimental diets for 12 weeks. Weight gain of fish fed diet 1 (control) and 3 were significantly higher than those of fish fed diet 2, 4 and 5 during the first 4 weeks (P< 0.05), while there were no significant differences among all diet groups during the third 4 weeks (P>0.05). Feed conversion ratio of fish fed diet 1 was significantly higher than those fed diet 2, 3, 4 and 5 during the second 4 weeks (P<0.05), while there were no significant differences among all diet groups during the first and the third 4 weeks (P<0.05). There were no significant differences in proximate analysis among fish fed the experimental diets either for the second 4 weeks or the third 4 weeks (P>0.05). These results indicated that ABPM could be used as a fish meal replacer up to $100\%$ in growing common carp.

• Journal of Animal Science and Technology
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• v.53 no.5
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• pp.489-496
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• 2011

This study was carried out to investigate the effects of stocking density on the eating and ruminating behavior of growing Hanwoo steer (Bos taurus coreanae). A total of thirty growing Hanwoo steers were divided into four stocking density groups (G1: 1 head/32 $m^2$, G2: 2 heads/32 $m^2$, G3: 3 heads /32 $m^2$, G4: 4 heads/32 $m^2$) with 3 replicates (12 pens). The results of eating behaviors for 48 hours are summarized as follows: Total intake was higher in 2G, 3G and 4G than in 1G, but not significantly different among thetreatments. Intake of roughage was the highest in 2G (3.32 kg), while 1G (2.85 kg) was the lowest (P<0.05). Eating time of concentrate was highly in the order of 1G > 2G > 3G > 4G (P<0.05). But eating time (concentrate + roughage) and ruminating time were not significantly difference among the treatments. Resting time (standing + lying) was the highest in 4G (P<0.01), and lying time was the highest in 2G. Chewing time (Eating + ruminating) was higher in 3G than in 1G, 2G, and 4G (P<0.05). Number of bolus, number of total chews, ruminating time per bolus and number of bolus per minute were not significantly difference among the treatments. But number of chews per bolus was significantly lower in 1G than those of the other treatments (p<(0.05). Number of urinating was in the order of 1G > 4G > 2G > 3G (P<0.05). However, stocking density had no effect on drinking and defecating. Eating rate and chewing efficiency were the highest in 4G (P<0.01, 0.05), but ruminating efficiency was not significantly difference among the treatments.

• Korean journal of applied entomology
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• v.24 no.2 s.63
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• pp.51-60
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• 1985

This paper was performed to study the nature of varietal resistance of some Korean-new rice cultivars to the brown planthopper (BPH), Nilaparvata lugens ($ST{\AA}L$). The rice cultivars tested were Cheongcheong, Gaya, Hangangchal, Samgang, Nampoong and Yeongpoong which have been reported as having resistant genes for the BPH. The check varieties were Jinheung, Sangpoong and Chucheong for susceptible and IR-36 for resistant. The factors studied were referred to the seedling responses, preference in feeding and oviposition of BPH, antibiosis (nymphal development, adult emergence and sex ratio, adult body weight, population build-up, feeding amount and amylase activity), and chemical composition (inorganic components, chlorophyll contents, cell wall components, amino acids and esterase isozymes) of leaf- sheath and/or roots of rice plants. In conclusion, the natures of varietal resistance of rice cultivars to the BPH were not only correlated with the resistant reaction of rice plant, but also they were related with the non preference in feeding and oviposition and those resistant cultivars had the antibiotic effects to the insects. Their antibiotic effects of rice cultivars to the BPH would be related with some of the chemical components of rice plants, such as the contents of magnesium oxide (MgO), and chlorophyll and the different esterase isozymes.