• Animal Bioscience
• /
• v.36 no.6
• /
• pp.943-952
• /
• 2023

Objective: For decades, LYD ([Landrace×Yorkshire] ♀×Duroc ♂) pigs are the most commonly-used commercial breed for meat production in Korea. Recently, due to the increasing demand for premium pork, the National Institute of Animal Science (Korea) has synthesized a novel pig breed named Woori Heukdon (WHD). This study aimed at comparing the carcass traits, meat yield and quality characteristics between the LYD and WHD pigs under identical rearing condition. Methods: The WHD and LYD pigs (n = 15 each) were reared under identical conditions and fed the same commercial diet until reaching recommended market weight (100 to 120 kg). After slaughter, the carcasses were evaluated for traits and meat yield, and the meat quality was assessed on shoulder butt and belly cuts. Results: Although no significant differences (p>0.05) occurred in slaughter weight between two pig types, WHD had a lower meat yield (by about 6 kg corresponding to approximately 7%) compared to the LYD pigs (p<0.05). The WHD had a higher fat content (by 4.26% and 13.52% in the shoulder butt and belly, respectively) compared to those of LYD pigs (p<0.05). The WHD meat showed a lower cooking loss and higher a* (redness) value (p<0.05). The WHD belly had a significantly (p<0.05) higher oleic acid content and concentrations of nonanal, octanal and decanal associated with fatty odor while, the LYD meat had a higher number of pyrazines associated with roasty odor. Regarding sensory quality, higher flavor, juiciness, and acceptability higher scores were given for the WHD meat than for the LYD meat (p<0.05). Conclusion: Under identical rearing conditions the WHD exhibited a better meat quality and sensory properties. However, the use of this diet resulted in a high fat level that may be associated with high trimming loss for the WHD.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.42 no.2
• /
• pp.109-115
• /
• 2009

The properties of surimi gel from Olive flounder Paralichthys olivaceus were evaluated with addition of various food additives and by heating under different conditions. The optimum heating conditions for get good textured surimi gel from Olive flounder was 40 minutes at $85^{\circ}C$. Optimum texture characteristics such as hardness, cohesiveness, chewiness, gumminess and gel strength of olive flounder fish paste can be acquired by washing the paste 2 times and by adding sodium chloride (2.5%), sodium polyphosphate (0.3%) and starch (4%), respectively. Furthermore, we compared gel texture characteristics and strength of manufactured Olive flounder fish surimi with commercial Alaska pollack to determine their commercial applicability. Texture characteristics and gel strength of Olive flounder surimi were higher than those of the commercial Alaska pollack surimi. In addition, both lightness and whiteness were higher in surimi gel from Olive flounder than from the commercial Alaska pollack.

• Korean Journal of Poultry Science
• /
• v.49 no.2
• /
• pp.89-98
• /
• 2022

This study compared the production and physiological characteristics of male and female Korean native commercial chickens. We investigated the growth performance, vitality, and stress response of 479 male and 608 female chickens from 1 d to 12 weeks of age. The body weight, feed consumption and feed conversion ratio were measured as growth performance. The survival rate, amount of telomeric DNA, DNA damage rate, heterophil-lymphocyte ratio (H/L ratio), and heat shock protein (HSP)-70, HSP-90α, and HSP-90β gene expression levels were analyzed as indicators of vitality and stress response. Body weight was significantly higher in male chickens than in female chickens after 2 weeks of age (P<0.01). Feed intake was higher in male chickens than in female chickens, whereas the feed conversion ratio showed the opposite trend. The survival rate was significantly higher in female chickens than in male chickens (82.8% vs. 73.8%, P<0.05). Stress response analysis revealed no differences between male and female chickens in terms of telomeric DNA content, DNA damage rate, H/L ratio, and HSP gene expression levels. Taken together, it was concluded that there was a significant difference in the growth performance and survival rate between male and female Korean native commercial chickens, whereas there was no difference in the degree of stress response between them. Therefore, in terms of the productivity of Korean native commercial chickens, it is judged that separate-sex rearing is much more advantageous than mixed rearing, regardless of the physiological characteristics of males and females.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.13 no.1
• /
• pp.1-5
• /
• 2006

The major dominant fluoride-endurance (Dfe) gene was introduced into the commercial varieties by crossing and pedigree selection to breed silkworm races that could normally develop in the area that polluted by fluoride. After backcrossed for two generations, the Dfe gene was made homozygous, and individuals with good economic characters were selected to generate next generation. After 8 generations of selection, their characters became stable, and the silkworm variety which is resistant to fluoride, Huayuan${\times}$Dongsheng, for spring rearing were bred.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.7 no.2
• /
• pp.191-195
• /
• 2003

The impact of antibiotic (Norfloxacin) administration ,at different concentration (50 ppm and 100 ppm) on commercial characters of bivoltine $({CSR_2}{\times}{CR_4})$ and the cross breed race $({BL_67}{\times}{CSR_101})$ was studied. The result indicated that antibiotic administration with different concentrations significantly improved the rearing and cocoon parameters like larval duration, larval weight, growth index, single cocoon weight, single shell weight and shell ratio. The post cocoon parameters like average filament length, non-breakable filament length, raw silk percentage, raw silk recovery percentage, denier, reelability and neatness were recorded significantly higher in antibiotic treated batches. The better performances of these parameters were recorded with the increase of antibiotic concentration.

• Asian-Australasian Journal of Animal Sciences
• /
• v.11 no.6
• /
• pp.774-780
• /
• 1998

This report includes an extensive bibliography of research articles investigating various facets of rearing neonatal piglets using liquid diets, and includes historical publications dating back to the 1940's. However, in order to provide concise and timely focus for application in modem swine production, only a selected number of recent findings are reviewed in detail. Collectively, the data presented illustrate that growth of piglets fed liquid diets can greatly exceed that of littermates fed dry diets and can even exceed growth rates of sow-reared controls (by up to 160%). The central questions that remain unanswered are: 1) Can this improved performance be obtained routinely and economically under applied farm conditions? and if so, 2) Does improved growth during the early-weaning period translate into improved net economic returns overall? Unfortunately, due to the current practical management constraints related to liquid-diet feeding (i.e., lack of an easy-to-manage feed delivery system), limited data are available which examine the efficacy of liquid-diet feeding under practical, commercial farm conditions.

• Korean Journal of Veterinary Research
• /
• v.33 no.2
• /
• pp.263-268
• /
• 1993

This study was conducted to detect the serum antibody of toxoplasma in swine from breeding-pig, rearing-pig farm and slaughtered pig in abattior by latex agglutination(LA) test. The perfomance of LA test was carried out with commercial Toxo-MT kit(Eiken Chemical Co.)by Tsubota and Ozawa's method. The cut-off titer of positive and negative reactions by Toxo-MT antigen used in this experiment was determined as the serum titer of 1 : 32. Positive rate of toxoplasma antibody from the total of 823 serum samples by LA test was 17.0%(140 cases). And positive rates of toxoplasma antibody against serum samples of 194 from breeding-pig farm, 273 from rearing-pig farm and 356 from abattior were 91 cases(46. 9%), 23 cases(8.4%) and 26 cases(7.3%), respectively. The distributions of serum antibody titers in 823 test sera by LA test were shown 51 cases(36.3%) in 1:32, 40(28.6%) in 1:64, 17(12.1%) in 1:128, 14(10.0%) in 1:256, 3(2.1%) in 1:512, 5(3.6%) in 1:1024 and 3(2.1%) in 1:2048. The ranges of positive rate from the sera in each group of breeding-pig farms were 20~61.9%.

• Asian-Australasian Journal of Animal Sciences
• /
• v.10 no.6
• /
• pp.657-664
• /
• 1997

432 Babcock ISA white leghorn pullets reared for 8 weeks on a standard managemental conditions were exposed to feed/nutrient and light restrictions from 9 to 20 weeks of age. Four feeding regimes i. e. 100, 85 or 70 percent of the recommended allowance and low energy (2,500 Kcal/kg) low protein (13% CP) ration were fed each in the three light regimes i. e. (A) Natural day light starting from 13.24 hr/day at 8 weeks of age and ending 10.41 hr/day at the end of 20 weeks; (B) Constant 11 hr/day light and (C) starting with 13 hr/day at 8 weeks and decreasing @ 20 min/week till 20 weeks of age. At the age of 20 weeks all the birds were shifted to separate cages under uniform lighting feeding and management. During the 21st week light was increased to 12 hr a day and thereafter with an increase of 30 min per week, increased to 16 hr a day at the age of 29 weeks. From 20 weeks onward till 72 week age, all the birds were offered commercial layer rations ad libitum, prepared according to climatic conditions. The results of the study revealed that birds reared under natural and constant light had higher weights than decreasing light, yet they could not out perform during production period. The effect of feed and nutrient restriction, on the other hand, was found significant during rearing as well as production period. The birds exposed to higher level of feed and those exposed to nutrient restriction were lighter in weight. The 100% fed birds laid their first egg at an early age. However, those reared on 85% of the recommendation excelled all other groups in terms of produced number of eggs, egg mass, hen housed and hen day production and net returns.

• Korean Journal of Poultry Science
• /
• v.10 no.2
• /
• pp.113-121
• /
• 1983

In an effort to understand epizootiological aspects of infectious laryngotracheitis (ILT), a total of 56 chicken flocks in six farms comprised of 35 broiler breeder, 13 commercial layer and 6 layer breeder flocks. were investigated. The farms experienced ILT during the period of one year from June, 1982. In most farms the birds were vaccinated against ILT just before or after the disease outbreak. In two of the farms in which ILT broke out in winter, it was possible to contain the disease in only one or two fleets without transmitting it to the remaining 5 to 7 flocks in the farms by adopting strict isolation procedures for the affected flocks. In regarding inter- flock spreading speed, it took an average of 6 days for flocks rearing on floor and 11 days for those in cages. Among the flecks in rearing cages. transmission among laying flocks was much faster. taking an average of 8 days, compared to non-laying flocks of 17 days, suggesting spreading of the disease by means of egg trays or egg collection process. Peak mortality was observed between 5 and 10 days after from the time of appearance of first dead birds from the disease and the period of mortality, with an average of 18 days, was not influenced by rearing systems, breeds and age of birds. Mortalities in the affected flocks ranged from lo/e to 19.8%, with an average of 6.5 %, and was also not influenced by the above variables except significantly lower mortality in immature broiler breeder flocks (2.9%) compared to immature layer (11.8%) and mature broiler breeder flocks (6.9%). In one breeder farm in which all the birds were kept on floor and ILT broke out in summer, mortality in male birds in all seven flocks of 37 weeks of age or older was as high as twice of that in female birds in the same flocks. This trend was not observed in one 31 weeks old flock and was reversed in another 14 weeks old flock in the farm.

• Journal of Aquaculture
• /
• v.11 no.1
• /
• pp.39-48
• /
• 1998

Growth performance and excretions of nitrogen (N) and phosphorus (P) were investigated with carp (Cyprinus carpio) with carp (Cyprinus carpio) grower fed a low pollution diets (A and B) and commercial ones (Com-1 and Com-2). A recirculated rearing system (Exp. I) and a floating net cage system (Exp. II) were employed for two feeding trials in which fish having an initial body weight of 152g and 193g were fed for 41 an 39 days, respectively. The highest weight gain, daily growth rate and protein efficiency ratio were found (P<0.05) in fish fed diet A containing 10% fish meal and 2% monocalcium phosphate (MCP) for both experiments. They also showed the lowest feed conversion ratio and daily feeding ration among treatments. Fish fed diet B containing 10% fish meal, 5% fish protein concentrate and 1% MCP showed weight gain and FCR more improved (P<0.05) than those fed commercial diets. In all groups, whole body cmpositions were not greatly different among treatment, and protein and P contents in final fish ranged from 14.3 to 15.6% and from 0.39 to 0.48%, respectively. Fish fed diet A excreted the least N which were 38.3 in Exp. I and 39.6g/kg gain in Exp. II. However, the values found in fish fed two commercial diets amounted to 59.1 and 58.9g, respectively. A significant decrease in P excretion was also found in fish groups fed diets A and B. In Exp. I, a reduction of 53.4% was shown in fish fed diet A, compared to the averaged value (18.5g P/kg gain) of two commercial groups. In Exp. II conducted using the floating net cages, fish fed diet B excreted the least P (8.6g/kg gain) among the treatment, which was followed by fish fed diet A, showing 48.6% reduction compared to the average value (18.5g/kg gain) for fish fed two commercial diets. The present results clearly showed that N and P excretions from fish culture could be significantly reduced by using the low pollution diet.