• Asian-Australasian Journal of Animal Sciences
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• v.11 no.5
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• pp.559-565
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• 1998

This study was conducted to investigate the effects of different feeding regimen on the growth and nutrients excretion in finishing pigs. A total of 80 pigs (59.91 kg BW) and 6 pigs (85 kg BW) were employed in a growth trial and metabolic trial, respectively. Treatments were grower-grower (GG), grower-early finisher(GE), early finisher-early finisher (EE), and early finisher-late finisher (EL) diet feeding regimens for feeding trial and G, E, L diets for metabolic trial. Through whole experimental period, no significant difference was found in any of the criteria measured. Pigs fed on a GG regimen gained slightly faster than pigs fed on other feeding regimens, with no significant difference. Although there was a trend that pigs fed on a GG or GE regimen showed improved feed/gain over pigs fed on a EE or EL regimen, the difference also was not significant. In the metabolic trial, dry matter and phosphorus digestibility was not affected by diets, however, phosphorus digestibility tended to be decreased as nutrients contents was decreasing in the diets. Crude protein digestibility was significantly influenced by the nutrients contents in th diets. The data suggested that 11.7% crude protein seemed to be low for the 85 kg pigs. Though nutrients excretion was not significantly influenced by dietary treatment except phosphorus, there was a trend that pigs fed diets with low nutrient content excreted less amount of nitrogen and phosphorus than pigs fed diets with high nutrients content. There was a trend that GG or GE feeding regimen gad a favorable effect on carcass grade when only 10 lighter pigs of each treatment were subjected to statistical analysis. However, with 10 heavier pigs, EE and EL feeding regimen showed better carcass grade, though the difference was not significant. In summary, it seemed that producers generally oversupply the expensive nutrients for the finishing pigs. High nutrient diets do not always guarantee high growth rate of pigs. It rather seems that to meet nutrient requirements for the each growth phase is more important in economical pork production.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.11
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• pp.1629-1634
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• 2008

A trial was conducted to determine the effect of low crude protein (CP) diets with constant metabolizable energy to crude protein (ME:CP) ratio on growth, body composition and nutrient utilization of broiler chicks from 1 to 26 days of age. Four dietary treatments having four levels of CP and ME as 23, 22, 21 and 20% and 3,036, 2,904, 2,772 and 2,640 kcal/kg, respectively, were formulated and a ME:CP ratio of 132 was maintained in all the diets. Digestible lysine was maintained at 1.10 of the diet. A total of 1,760 day-old Hubbard broiler chicks were randomly divided into 16 experimental units and each diet was offered to four experimental units at random. Feed intake was increased (p<0.05) while weight gain and feed conversion ratio were adversely affected (p<0.05) when the diets with low CP and ME were fed to broilers. Total protein intake and total ME intake were linearly decreased (p<0.05) and protein efficiency ratio and energy efficiency ratio were lower (p<0.05) than in the chicks fed dietary regimen with 22% CP and 2,904 kcal/kg ME. The whole body analysis of the birds revealed that chicks fed the lowest dietary regimens retained less (p<0.05) nitrogen and more ether extract than chicks fed the control diet, however, body dry matter, total body ash and fat free body protein were not affected. Similarly, protein and energy utilization were also unaffected by the dietary treatments. In summary, chicks fed low CP diets with constant ME:CP ratio grew slower, used feed less efficiently and retained less protein and more body fat than chicks fed the control diet.

• Korean Journal of Poultry Science
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• v.42 no.3
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• pp.205-214
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• 2015

This study aimed to investigate the effects of reducing feed intake on performance and meat quality in old laying hens. A total of 200 Hy-Line Brown laying hens (100 weeks old) were randomly allotted to five dietary treatments: control (100% daily feed intake), 90%, 60%, 50%, and 20% daily feed intake. Each treatment was replicated four times with 10 birds per replication and two birds per cage. Ten-bird units were arranged according to a randomized block design. The feeding trial lasted for 4 weeks under a 16L:8D lighting regimen. The results indicated that the daily feed intake correlated with hen-day egg production and feed conversion ratios (P<0.05). The carcass yields and partial ratios were also correlated with daily feed intake (P<0.05). The levels of leukocytes (without basophils) were higher in the 50% and 20% daily feed intake groups than in the other groups. The concentrations of dry matter, crude ash, crude fat, and crude protein, water holding capacity, cooking loss, and fatty acids in the breast meat did not decrease as the daily feed intake decreased. In conclusion, reducing daily feed intake decreased laying performance and carcass yield but had no effect on breast meat quality.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.1
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• pp.18-21
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• 1999

A feeding experiment was conducted to determine the effects of feeding frequency on growth and body composition in juvenile olive flounder (Paralichthys olivaceus). Triplicate groups of the 40 fish averaging 1.6 g were fed the 2 different commercial diets (D-1 and D-2) and moist pellet (MP) contained frozen horse mackerel and commercial binder meal at different feeding frequencies of 4 times daily, 3 times daily, 2 times daily, once a day or once in 2 days. Growth and feed intake of fish were affected by diets and feeding frequencies (P<0.05). Feed intake ($\%$ of body wt.) in the all diet groups was significantly decreased according to feeding frequency decreased (P<0.05). Weight gain of fish fed the each diet were increased according to feeding frequency increased, although no significant differences were observed between 3 times and 4 times daily (P>0,05). If the same feeding frequency, feed intake and growth of fish fed the moist pellet were lower (P<0.05) than those of commercial diets (D-1 or D-2), probably due to the relatively high moisture content or unbalanced nutrients. Whole body lipid content of fish fed the each diet at once in 2 days was the lowest among feeding frequencies. These results indicate that 3 times daily feeding regimen may be more effective than that of 4 times daily and moist pellet in this study will not be used as a practical type of diet for juvenile olive flounder weighing between 1,6 g and 4 g.

• Korean Journal of Poultry Science
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• v.30 no.3
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• pp.169-175
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• 2003

This experiment was conducted to study the optimum energy feeding regimens fur broiler breeders peaked in winter season with 400 caged hens of Ross strain. Four energy supply regimens which were different in daily energy allotment during laying period were employed for 40 weeks from 24 to 64 weeks of age. All experimental diets were formulated to contain 2,750 kcal ME/kg with adjustments made in total feed allotment to provide the desired energy levels. Total consumption of the feed would provide 20 g of protein, 4 g of calcium and 0.35 g of available phosphorus. There were no difference in hen-day egg production and average egg weight among the regimens of energy supply. Feed, ME and feed cost required per egg or per kg egg were significantly increased as the level of energy allotment increased(p<0.05). It was concluded that the energy supply regimen, which supplied 280 kcal ME per day at the age of 24 weeks and then increased the energy supply up to 400 kcal ME per day at the peak period of 30∼34 weeks of age, was superior in feed, ME and feed cost required per egg or per kg egg without any adverse effect on eg production and egg weight.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.1
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• pp.149-156
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• 2018

Objective: Broilers show clear preference towards red color light (RL). However setting of an optimum light intensity is difficult since dim intensities that favor growth reduce welfare. This experiment was conducted to test the most effective RL intensity regimen (Dim [5 lux; DI] vs high [320 lux; HI]) in combination applied at different growth stages that favors for both performance and welfare. Methods: Complete randomize design was adopted with 6 replicates. Treatments were; T1 = early DI (8-21 d)+latter HI (22-35 d); T2 = early DI (8-28 d)+latter HI (29-35 d), T3 = early HI (8-21 d)+latter DI (22-35 d), T4 = early HI (8-28 d)+latter DI (29-35 d) and T5 = control (white light; WT) (8-35 d) at medium intensity (20 lux). Body weight (BW), weight gain (WG), water/feed intake and ratio, feed conversion ratios (FCR) were assessed. Common behaviours (15) were recorded by scan sampling method. Lameness, foot pad dermatitis, breast blisters, hock burning damage were assessed as welfare parameters. Fear reactions were tested using Tonic Immobility Test. Ocular and carcass evaluations were done. Meat and tibiae were analyzed for fat and bone ash respectively. Results: On 35 d, the highest BW ($2,155.72{\pm}176g$), WG ($1,967.78{\pm}174g$) were recorded by T2 compared to WT ($BW_{WT}=1,878.22{\pm}155$, $WG_{WT}=1,691.83{\pm}160$). But, application of RL, either DI, or HI during early/latter stage had no significant effect on FCR. Under HI, birds showed much higher active behaviours. DI encourages eating. Though LI changed from DI to HI, same trend could be seen even under HI. The highest leg strength ($218.5{\pm}120s$) was recorded by T2. The lowest leg strength ($64.58{\pm}33s$) and the highest ocular weight ($2.48{\pm}1g$) were recorded by T1. Significantly (p<0.05) the highest skin weight ($162.17{\pm}6g$) but the lowest fat% in meat ($13.03%{\pm}5%$) was recorded by T2. Conclusion: Early exposure to DI-RL up to 28 days followed by exposure to HI-RL is the most favorable lighting regimen for optimizing production, better welfare of broilers and improving health benefits of meat.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2000.11a
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• pp.81-84
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• 2000

Effects of different photoperiod regimens on the cellular and humoral immunity in broiler chickens were studied(Exp 1). Total one hundred ninety two one-day-old commercial broiler chicks(Cobb$\times$Cobb) were raised between constant lighting(CL) and intermittent lighting (1h light: 3h darkness(IL; 1l; 3D) Body weight, feed intake and feed conversion were measured for seven week. Peripheral blood and splenic lymphocyte activities were tested at 3 and 5 wk of age by performing a mitogen cellproliferation assay with a polyclonal T-cell mitogen, concanavalin A (Con A), and B-cell mitogen, lipopolysaccharide (LPS). To investigate the effect of photoperiod on the humoral immunity, chicks were immunized with sheep red blood cell(SRBC) and iinactivated Newcastle disease virus(NDV) vaccine. Total immunoglobulin G(IgG) concentration was also determined. Diurnal change of melatonin was tested in sera. In experiment 2, 0.1ml melatonin were subcutaneously injected from three to five weeks old if immunomodulation effect of lighting regimen was due to the melatonin or not. Injections of melatonin were made at 0700h and the dosage was 10ng (M2), 100ng(M3), 1$\mu\textrm{g}$(M4) per bird daily, respectively. control were quivalent injections of vehicle(M1). Lymphocyte activities were tested and humoral immunities were examined at 5 weeks of age. Blood melatonin concentration was determined at 0h, 1, h, 2h, and 3h posterior to injection at five weeks old. It was higher in CL chicks than IL chickens during the subsequent period of 3 to 5 wk of age. However, weight gain of chicks raised IL were significantly higher at 6 wk of age than CL(P<0.05). Antibody response to NDV was not affected by both photoperiod regimens and melatonin injection, whereas anti-SRMB titer and IgG concentration were enhanced. Lymphocyte activity of chickens raised under IL was sighificantly higher than those of chickens raised under CL. Melatonin injection also increased lymphocyte activity. When peripheral blood lymphocytes were used, proliferation response to LPS and Con A were significantly increased in M2 and respectively. The results of this experiments suggest that IL improved host immune response and melatonin have immunomodulatory roles.

• Journal of Life Science
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• v.21 no.5
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• pp.684-692
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• 2011

The present study furthered this research by determining the optimal level of inuloprebiotics derived from Korean Jerusalem artichoke to promote growth in broiler chickens. On hatch day, 320 male Ross 308 broilers were randomly allotted to four groups for a 35-day feeding regimen. The groups were a control (no supplementation), diet supplementation with antibiotics (8 ppm avilamycin), supplementation with 200 ppm inuloprebiotics, and supplementation with 250 ppm inuloprebiotics. Body weight and feed intake were comparably high in the two inuloprebiotics groups, and exceeded the values for the control and antibiotics groups. Body weight and feed intake was higher in chickens fed the antibiotics supplemented diet, compared to controls. There were significant differences among treatment groups. Feed conversion ratio during total experimental periods was significantly high in the control group compared to the inuloprebiotics-fed groups, but no significant difference was evident using antibiotics or inuloprebiotics dietary supplementation. Carcass weight, dressing percentage, and weight of breast and thigh muscle were significantly higher for inuloprebiotics-fed chickens, compared with control and antibiotic-fed chickens. Inuloprebiotics concentration was not significant, while antibiotics-fed chickens displayed significantly higher values than control chickens. Abdominal fat was significantly reduced (19.08%-23.30%) and blood immunoglobulin and the weight of the thymus and Bursa of Fabricius were significantly increased in chickens receiving inuloprebiotics-supplemented feed, compared to control and antibiotics fed groups. In the lower intestine, the viable counts of beneficial bacteria (Bifidobacteria and Lactobacillus) were significantly increased and counts of harmful bacteria (Escherichia coli and Salmonella sp.) were significantly decreased in the presence of the inuloprebiotics, compared to control and antibiotic. The present results support 200 ppm as an optimal level of Korean Jerusalem artichoke-derived inuloprebiotics as a dietary supplement to improve growth in broiler chickens.

• Journal of Aquaculture
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• v.9 no.4
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• pp.385-394
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• 1996

A 15-week feeding experiment was conducted to determine the effects of feeding frequency from 2 different formulated diets on growth, feed efficiency and body composition in juvenile Korean rockfish (Sebastes schlegeli). Duplicate groups of the 30 fish averaging 25 g were fed the control diet containing $58\%$ fish meal and the experimental diet containing $40\%$ fish meal, $10\%$ meat meal, $3\%$ corn gluten meal, $3\%$ soybean meal, and $3\%$ blood meal as protein sources at different feeding frequencies of 2 times daily, once a day in the morning or afternoon, once in 2 days, or given no food. Growth and feed efficiency of the fish were affected by diets (P<0.05), whereas these values were unaffected by feeding frequencies (P>0.05). Feed intake (${\%}$ of body wt.) of the fish fed once in 2 days was lower than that of the fish fed 2 times daily and once a day (P<0.05), Moisture, protein, lipid and ash contents of liver and muscle were not influenced by different diets and feeding frequencies (P>0.05). These results indicate that once a day or once in 2 days feeding regimen must be more effective and economical than that of 2 times daily for juvenile Korean rorkfish.