• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.5
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• pp.546-551
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• 2013

This study examined the effects of the dietary inclusion of Porphyra and sea tangle Laminaria japonica on the growth, feed utilization, body composition, and plasma chemistry of juvenile Korean rockfish Sebastes schlegeli. Eight hundred and forty juvenile fish averaging 5.0 g were allocated 40 fish per tank to 21 180-L flow-through tanks. Seven experimental diets were prepared: control (Con) without additive, 0.5 and 1% Porphyra extract (PE), 3% Porphyra powder (PP), 0.5 and 1% sea tangle extract (STE) and 3% sea tangle powder (STP), referred to as PE-0.5, PE-1, PP-3, STE-0.5, STE-1, and STP-3, respectively. Each additive was included in the experimental diet at the expense of the same amount of wheat flour. Each experimental diet was fed to triplicate groups of fish. The experimental diets had no effect on the survival, weight gain or specific growth rate of the fish, feed consumption, feed efficiency ratio, protein efficiency ratio, protein retention, hepatosomatic index, condition factor, moisture or crude protein content of the entire body excluding the liver or moisture, crude protein or crude lipid content of the liver. None of the plasma parameters were affected by the experimental diets. Based on these results, the dietary inclusion of Porphyra and sea tangle did not affect the growth, feed utilization, body composition or plasma chemistry of juvenile Korean rockfish.

• Korean Journal of Agricultural Science
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• v.44 no.2
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• pp.244-253
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• 2017

This study was conducted to investigate the growth performance indices among male commercial crossbred Korean native chickens from hatch to twelve weeks of age. A total of 312 one-day-old male birds were used for 6 groups of the commercial crossbred Korean native chicken within 1 paternal line and 6 maternal lines (1A, 2A, 3A, 4A, 5A, and 6A). The chickens were allocated to 24 battery cages to give 4 replicates per each crossbreed with 13 chickens per cage. Ad-libitum feeding was practiced throughout the experimental period and fresh water was available via nipple drinkers at all times. Body weight and feed intake were measured at two-week interval. Among six crossbreeds, the 2A group had the greatest (p < 0.05) body weight at week 8 and the greatest average daily weight gain in week 6 - 8. However, crossbreed 2A had the lowest viability (p < 0.05) at week 8 of all crossbreed groups as well as higher uniformity (p > 0.05) at week 2 than the others. No difference (p < 0.05) was found in any crossbreed Korean native chicken's growth performance indices including body weight, average daily gain, average daily feed intake, feed efficiency, uniformity, and viability after week 8. With this in mind, crossbreed 2A had greater bodyweight, average daily gain, average feed intake, and feed efficiency than the other Korean native chickens 84 days after hatch, although they had lower uniformity and viability than the others.

• Asian-Australasian Journal of Animal Sciences
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• v.2 no.1
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• pp.1-6
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• 1989

Nutritive values and fermentation rates of rice straw treated with 3% anhydrous and 3% aqueous ammonia were evaluated both in vitro and sheep metabolism trials. Daily gain, feed efficiency and feed cost per gain were also determined with growing Holstein bulls fed anhydrous and aqueous ammonia treated rice straw. Crude protein was increased 2.4 fold and NDF was decreased 6.5%, but ADF and cellulose were not different between untreated and ammonia treated rice straw. An average of 35.5% of total added ammonia-N retained in the rice straw and other 64.5% was not retained in the rice straw. Ammonia treatment increased in vitro DM, NDF, ADF and cellulose digestibilities by 44.8%, 43.3%, 49.4% and 42.4%, respectively, and fermentation rates by 63.3%, 132.4%, 49.4% and 42.4%, respectively. In sheep metabolism trials, DM digestibilities of rice straw treated with anhydrous and aqueous ammonia were increased 22% and 36%, respectively, and digestible DM intakes by 48% and 70%, respectively in sheep fed anhydrous and aqueous ammonia treated rice straw over untreated rice straw. Rumen ammonia and blood urea were considerably higher in sheep fed ammonia treated rice straw than sheep fed untreated rice straw. Daily gain of Holstein bulls was increased 20.8% and 29.9% and rice straw intakes were increased 28.4% and 44.3% in anhydrous and aqueous ammonia treated rice straw over untreated rice straw. Feed conversion was improved 9.5% and 10.3% and feed cost/gain was reduced 7.1% and 9.2% respectively in anhydrous and aqueous ammonia treated rice straw group as compared with untreated rice straw group.

• Fisheries and Aquatic Sciences
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• v.7 no.4
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• pp.184-191
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• 2004

A 25-week feeding trial of two dietary protein (47 and $52\%$) and three dietary lipid level (7, 12 and $17\%$) factorial design with three replications were conducted to determine effects of dietary protein and lipid levels on growth, feed utilization and body composition of adult starry flounder (Platichthys stellatus), average initial weight 332 g, during the winter season. Survival of fish was not affected by either dietary protein or dietary lipid level. Weight gain, feed efficiency and protein efficiency ratio improved with dietary protein and lipid levels except for those of fish fed the $52\%$ protein diet with $17\%$ lipid. The best growth and feed utilization were observed in the $52\%$ protein diet with $12\%$ lipid, but were not significantly different from those of fish fed the $52\%$ protein diet with $17\%$ lipid or the $47\%$ protein diets with $17\%$ lipid levels. Hepatosomatic and visceral somatic indexes were significantly influenced by dietary protein level, but not by dietary lipid level. None of moisture, crude protein, crude lipid, or glycogen contents of dorsal muscle or liver in starry flounder except for crude lipid in dorsal muscle was significantly influenced by either dietary protein or dietary lipid level. Plasma cholesterol concentration was significantly influenced by both dietary protein and dietary lipid levels. The results of this study suggest that the diets containing $47\%$ protein with $17\%$ lipid or $52\%$ protein with $12-17\%$ lipid are optimal for growth and feed utilization of adult starry flounder under these experimental conditions.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.6
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• pp.823-829
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• 2016

Yacon (YC), ginger (GG) and blueberry (BB) were added to the diet of juvenile rockfish Sebastes schlegeli to investigate the effects of these substances on growth, feed utilization and resistance to Streptococcus iniae compared to feed additive ethoxyquin. A total of 480 fish were distributed in 12 tanks and four experimental diets [control (Con), with 0.01% ethoxyquin, and 1% YC, GG and BB diets] were provided in triplicate. After an 8-week feeding trial, 20 fish from each tank were infected with Streptococcus iniae. Fish fed the BB diet had higher weight gain than fish fed the GG and Con diets. Feed efficiency of fish fed the GG and YC diets was higher than that of fish fed the BB and Con diets. The protein efficiency ratio of fish fed the GG diet was higher than that of fish fed any other diet. The cumulative mortality 54 h after infection of fish fed the Con diet was higher than that of fish fed any other diet. These results indicate that YC, GG, and BB are effective dietary additive, not only improving growth performance and feed utilization but also lowering the mortality of juvenile rockfish exposed to S. iniae.

• Journal of The Korean Society of Grassland and Forage Science
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• v.37 no.3
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• pp.208-215
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• 2017

This study was designed to investigate the carryover effects of high-forage to concentrate (F: C) diet in bred heifers on feed intake, feed efficiency (FE) and milk production of primiparous lactating Holstein cows. The experiment was conducted for 589 days (d) from onset of pregnancy through to the end of first lactation. Twenty-four bred heifers (Body weight: $BW=345.8{\pm}45.4kg$ and $15{\pm}1.2mon$ of age) randomly assigned to two groups of 3 pens containing 4 heifers each and fed high forage (HF) diet with F: C ratio of 91.7: 8.3% and low forage (LF) diet with F: C ratio of 77.8: 22.2% throughout the pregnancy period. After calving, lactating cows were fed total mixed ration (TMR) based diet. No differences (p > 0.05) were observed in dry matter intake (DMI) of bred heifers and primiparous lactating cows in both HF and LF groups. The FE of mid-to-late lactation period was higher (p< 0.05) in HF than LF group. However, the HF group showed higher (p < 0.05) milk yield, 4 % fat corrected milk (FCM) and energy corrected milk (ECM) than LF group during the 305 d lactation. The LF group showed higher (p < 0.05) milk fat, crude protein (CP), milk urea nitrogen (MUN), solid not fat (SNF) and somatic cell count (SCC) than HF group. It is concluded that restriction of F: C ratio to 91.7: 8.3% to bred heifers has the potential carryover effects to maintain higher milk yield and FE with no adverse effect on feed intake and milk composition of primiparous lactating Holstein cows.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.8
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• pp.1122-1127
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• 2019

Objective: The objective of current study was to investigate the lactation performance and rumen fermentation characteristics of dairy cows fed a diet with alfalfa hay replaced by corn stover but supplemented with molasses. Methods: Sixteen Holstein cows in mid-lactation were randomly assigned to 1 of 2 dietary treatments: i) alfalfa based diet (AH), and ii) corn stover based diet supplemented with molasses (CSM). The experiment was conducted according to a $2{\times}2$ crossover design with 22-d each period, consisting of 17 d for adaptation and 5 d for data and samples collection. Results: Dry matter intake and milk yield were higher for cows fed AH than CSM (p<0.01). Milk protein content and nitrogen conversion were higher (p<0.05), while milk urea nitrogen was lower (p<0.01) for cows fed AH than CSM-fed cows. Contents of milk total solids, fat and lactose were not different between two groups (p>0.10). Total rumen volatile fatty acid concentration tended to be higher (p = 0.06) for cows fed AH than CSM-fed cows. Molar proportion of acetate was lower (p = 0.04), but valerate was higher (p = 0.02) in cows fed AH than CSM-fed cows. Rumen concentration of propionate, and isobutyrate, and ratio of acetate to propionate tended to be different (p<0.10) between two groups. The feed cost per kilogram of milk was lower in CSM than AH (p<0.01). No differences were found in feed efficiency and most plasma parameters tested (p>0.10). Conclusion: In comparison with AH diet, CSM diet could be fed to dairy cows without negative effect on feed efficiency, ruminal fermentation, but economically beneficial, indicating that CSM could be an alternative choice for dairy farms instead of AH to feed midlactation dairy cows.

• Fisheries and Aquatic Sciences
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• v.22 no.4
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• pp.8.1-8.9
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• 2019

A 12-week feeding trial was designed to evaluate the effect of total replacement of fish oil (FO) with terrestrial alternative oils on growth, feed utilization, body composition, hematological parameters, and fillet fatty acid profile of mandarin fish juveniles. Four iso-nitrogenous (56% crude protein) and iso-lipidic (13% crude lipid) practical diets were formulated. A control diet contained 6% FO and three other experimental diets were prepared by replacing FO with linseed oil, soybean oil, and lard (designed as FO, LO, SO, and lard, respectively). Each diet was randomly allocated to triplicate groups of 25 fish ($1.8{\pm}0.03g/fish$) in a circular tank. Complete replacement of FO by three tested alternative oils had no remarkable impact on growth performance, feed utilization efficiency, and morphological and hematological parameters of juvenile mandarin fish. However, daily feed intake was found to be significantly higher for fish fed the SO diet compared with those fed the FO and LO diets. Fish fed LO and SO diets exhibited significantly higher levels of the whole body lipid compared to fish fed diet containing FO. Fillet fatty acid composition reflected dietary fatty acid profile. The highest level of ${\alpha}$-linolenic acid, linoleic acid, and oleic acid was observed in fish fillet fed LO, SO, and lard, respectively. Although the eicosapentaenoic acid level of fish fillet fed diet FO was higher than other treatments, no significant difference was found in docosahexaenoic acid content among all dietary groups. The results of the present study clearly demonstrate that the complete replacement of FO in mandarin fish diets is achievable. These findings are useful in dietary formulation to reduce feed costs without compromising mandarin fish growth.

• Fisheries and Aquatic Sciences
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• v.24 no.6
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• pp.219-227
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• 2021

The effects of various feeding ratios on the growth, body composition, and blood chemistry of the juvenile mandarin fish Siniperca scherzeri (initial body weight 9.6 g) were examined in recirculating freshwater system equipped with 21, 300 L tanks at 20 fish per tank. The triplicate groups of seven feeding ratios treatments were prepared: 100% (control), 95%, 90%, 85%, 80%, 75%, and 70% of satiation. The feed amount of control group was determined by supplying with apparent satiation and then the feed amounts of the other six feeding groups were determined based on the feed amount of the control group. Fish were hand-fed with test diet (55.4% crude protein) for 10 weeks. Weight gain (WG) and specific growth rate of fish fed to 100% satiation were not significantly (p > 0.05) different from those of fish fed to ≥ 80% satiation but were significantly higher than those of fish fed to 75% and 70% satiation. Feed efficiency, protein efficiency ratio, and protein retention of 100% satiation were not significantly different from those of 95% and 90% satiation but were significantly (p <0.05) lower than ≤ 85% satiation. Condition factor, hepatosomatic index, and coefficient variation were not significantly (p > 0.05) affected by feeding ratio. Whole body composition and contents of hematocrit, glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, glucose, total protein, and high-density lipoprotein cholesterol in blood serum were not significantly (p > 0.05) affected by the feeding ratio; however, content of total cholesterol tended to decrease as the feeding ratio decreased. Using broken-line analysis of WG, it was suggested that the optimum feeding ratio of juvenile mandarin fish, ranging from 9.0 g to 37.0 g, appeared to be 87.7% of satiation without growth inhibition.

• Animal Bioscience
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• v.34 no.3_spc
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• pp.354-362
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• 2021

Broiler chickens grow rapidly, and their nutrient requirements change daily. However, broilers are fed three to five diet phases, meaning nutrients are under or oversupplied throughout production. Increasing diet phases improves production efficiency as there is less time in the production cycle that nutrients are in under or over-supply. Nevertheless, the process of administering four or more diets is costly and often impractical. New technologies are now available to blend feed to match the daily nutrient requirements of broilers. Thus, the aim of this review is to evaluate previous studies measuring the impact of increasing feed phases on nutrient utilisation and growth performance, and review recent studies taking this concept to the extreme; precision nutrition - feeding a new diet for each day of the production cycle. This review will also discuss how modern precision feeding technologies have been utilised and the potential that new technologies may bring to the poultry industry. The development of a precision nutrition regime which targets daily requirements by blending dietary components on farm is anticipated to improve the efficiency of production, reduce production cost and therefore improve sustainability of the industry. There is also potential for precision feeding technology along with precision nutrition strategies to deliver a plethora of other management and economic benefits. These include increased fluidity to cope with sudden environmental or market changes, and the ability to alter diets on a farm by farm level in a large, integrated operation. Thus, the future possibilities and practical implications for such technologies to generate a paradigm shift in feed formulation within the poultry industry to meet the rising demand for animal protein is also discussed.