• Animal Bioscience
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• 제37권3호
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• pp.500-508
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• 2024

Objective: Due to current selection practices for increased egg production and peak persistency, the production profile, age at maturity, and body weight criteria for commercial layers are constantly changing. Body weight and age at the time of photostimulation will thus always be the factors that need to be adequately addressed among various production systems. The current study was carried out to determine the effects of pullets' body weight (low, medium, and heavy) on their performance, welfare, physiological response, and hormonal profile. Methods: With regard to live weight, 150 16-week-old pullets were divided into three groups using a completely randomized design (CRD) and held until the 50th week. One-way analysis of variance was used to evaluate the data under the CRD, and the least significant difference test was used to distinguish between treatment means. Results: In comparison to the medium and light birds, the heavy birds had higher body weight at maturity, an earlier age at maturity, and higher egg weight, eggshell weight, eggshell thickness, egg yolk index, breaking strength, egg surface area, egg shape index, egg volume, and hormonal profile except corticosterone. However, the medium and light birds had lower feed consumption rates per dozen eggs and per kilogram of egg mass than the heavy birds. Light birds showed greater body weight gain, egg production, and egg specific gravity than the other categories. At 20 weeks of age, physiological response, welfare aspects, and catalase were non-significant; however, at 50 weeks of age, all these factors-aside from catalase-were extremely significant. Conclusion: The findings of this study indicate that layers can function at lower body weights during photostimulation; hence, dietary regimens that result in lighter pullets may be preferable. Additionally, the welfare of the birds was not compromised by the lighter weight group.

• 한국가금학회지
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• 제17권4호
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• pp.281-283
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• 1990

10주령 병아리를 이용하여 Cage당 10수로 하여 15반복의 시험구를 배치하였다. 10주령까지는 19％의 단백질사료로 사육되었으며 그 후에는 12％의 단백질사료를 이용하여 사육하였다. 대조구는 옥수수와 대두박구로 하고 시험구는 대조구의 대두박 대신 해바라기 씨앗으로 일부(19％) 또는 전부(38％)를 대치하여 19주령까지 사육하였다. 19주령에서 산란계용 cage로 옮긴 후 13.5％의 단백질 수준을 유지시켰다. 시험결과에 의하면 해바라기씨앗 첨가구는 19％ 대치한 구에서는 전 산란기간을 통하여 반 생산 및 능력이 대조구에 비하여 아무 차이가 없었다. 그러나 38％ 대치구에서는 약간의 성성숙 지연이 있었지만 전 산란기간을 통하여 얻어진 시험결과에 의하면 오히려 경제적으로 이익이었다.

• 한국가금학회지
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• 제39권4호
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• pp.261-267
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• 2012

Different housing systems have considerable influence on performance in poultry production. Therefore, the present study was undertaken to investigate the impact of different housing systems on the performance, bone mineral density and egg yolk fatty acid composition in laying hen. Hy-line brown pullets (n=450) of 12 weeks age were randomly divided into 3 housing systems with 6 replicates of 25 birds in each room. A diet with 2,750 kcal/kg ME and 16.5% CP was assigned to all birds. The pullets provided free access to feed and water. Significantly (P<0.05) higher values for egg production, egg mass and feed conversion efficiency were found in battery cages, however egg weight, egg shell color and breaking strength was remarkably (P<0.05) higher in floor system. The albumin height and Haugh unit were significantly higher (P<0.05) in battery cages which was statistically similar to aviary housing system. The egg yolk fatty acids concentration of linoleic acid and linolenic acids were significantly higher in aviary and in floor system, respectively, however both values were lower in battery cages. Saturated and unsaturated fatty acid content (%) in egg yolk did not influence by any housing systems. Bone mineral density was significantly higher (P<0.05) in floor and aviary housing system than that of battery cage system. It was concluded that in battery cages the egg production and composition maximized, however higher bone mineral density and yolk fatty acids content can be improved in the laying hen reared on floor and aviary housing systems.

• Asian-Australasian Journal of Animal Sciences
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• 제19권6호
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• pp.884-891
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• 2006

The effect of dietary vitamin E supplementation on immune responses was studied in breeder chickens during the maturing period. In experiment 1, 17-week old female birds were fed corn-soybean meal based diets supplemented with either 0, 40, 80, 120, or 160 mg vitamin E (all-rac-${\alpha}$-tocopherol acetate)/kg diet for 19 weeks. In experiment 2, 23-week old male birds were fed the corn-soybean meal based diet supplemented with either 0, 20, 40, 80 or 160 mg vitamin E/kg diet for 8 weeks. The chickens were evaluated for growth performance, antibody titer to sheep red blood cell (SRBC), Newcastle disease virus (NDV), infectious bursal disease virus (IBDV) and infectious bronchitis virus (IBV), and skin response to phytohemagglutinin-P (PHA-P). The results showed that supplemental vitamin E improved body weigh gain of laying pullets during peak-laying period but had no significant effect on growth performance of cockerels. For cockerels, addition of 20 mg vitamin E/kg diet significantly enhanced (p<0.05) immune response to SRBC compared to those added with 0, 80 and 160 mg vitamin E/kg diet; addition of 20 mg vitamin E/kg diet had higher (p<0.01) antibody titer to IBDV than those added with 40-160 mg vitamin E/kg diet. No significant effects on immune response were observed in laying pullets fed supplemental vitamin E. The findings suggest that moderate supplementation of vitamin E may enhance immune responses to selective antigens in cockerels but excessive vitamin E may depress specific immune response.

• 농업과학연구
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• 제38권4호
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• pp.659-665
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• 2011

This work was conducted to evaluate the hatching and growing performance of Korean Native Ducks (KND) Pure Breeding Line (PL). A total of 400 male and female pullets were produced from PL to keep in National Institute of Animal Science, Korea. Pullets were divided into 4 treatments, 5 repetitions per treatment, and 20 heads per repetition. Four treatments were compared in a $2{\times}2$ factorial arrangement with 2 groups (White strains, WW; Jade Green strains, CC) for their parents and 2 groups (male and female). Livability was not significantly different at 20 weeks among male and female of 2 strains. There was no significant difference on body weight and feed intake between WW and CC strains (P>0.05), but there was significantly different on body weight and feed intake between male and female (P<0.05). The feed conversion ratio of female was higher compared to male (P<0.05), but there was no significantly different between CC and WW strains. These results provide the basic data to develope the new strains of Korean Native Ducks.

• 한국수산과학회지
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• 제3권3호
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• pp.172-176
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• 1970

This research dealt with the nutrient value of the seaweed, Sargessum horneri (Turner) C. Ag. which showed the highest nutrient value in the previous exporiment (Park 1968). Its objective was to find the most effective mixing ratio of ordinary chicken feed used for pullet. In order to investigate the most effective mixing ratio, seven kinds of sample feed with vary-ing amounts of the seaweed as shown in table 2 were prepared and were fed to seven groups of chickens, each group consisting of twenty, four week old, pullets. In addition, the effect of sodium glutaminate mixed in the feed was also investigated, and the following result was obtained. The average increase in body weight of each group during the experiment period was determined. The group fed with the feed containing $10\%$ powdered Sargassum horneri (Turner) C. Ag. showed the highest body weight increase. In this experiment the body weight increase was accelerated by mixing $0.5\%$ sodium glutaminate In the above feed.

• Asian-Australasian Journal of Animal Sciences
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• 제5권1호
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• pp.91-95
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• 1992

Two experiments were conducted to evaluate the performance of broilers and layers fed locally produced fish waste meal (LFWM) in Western Samoa. LFWM, which was produced by mincing and oven drying of rejects from filleted fish, was included in both broiler and layer diets at the complete expense of imported meat and bone meal (MBM). The experiments were of a completely randomised design. In experiment 1, 120 day-old Strabro broiler chicks were raised to 49 days of ages. In experiment 2, 80 Shaver 288 pullets, 20 weeks of age, were housed in pairs in cages and raised up to 72 weeks of age. There were no differences (p > 0.05) in performance of broilers as measured in terms of final bodyweights, feed intake, feed efficiency and carcass yield between the two diets. Similarly, no differences (p > 0.05) existed in egg production, egg weight and feed required per kilogramme of eggs. It is concluded that LFWM is nutritionally as good as imported MBM and could be used to completely replace MBM in broiler and layer diets.

• 한국가금학회지
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• 제35권4호
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• pp.341-350
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• 2009

이 실험은 추백리의 병원성을 연구하고자 2006년 2월부터 12월까지 Salmonella enterica serovar. enterica subspecies (S.) Pullorum 야외주를 분리한 후, 이를 건강한 닭에 실험적으로 감염시킨 다음 임상증상, 여러 기관의 육안 및 조직병리학적 검색과 아울러 공격주의 재분리와 동정을 시도하였다. S. Pullorum에 혈청학적으로 음성인 12주령의 100수의 암탉을 $A{\sim}E$까지 20수씩 5그룹으로 구분하였다. $A{\sim}DS$. Pullorum을 $10^6\;CFU$, $10^7\;CFU$, $2{\times}10^7\;CFU$, $10^8\;CFU$로 각각 경구 감염시켰고, E는 비감염 대조군으로 삼았다. 실험 방법으로는 부검, 조직병리학적 검사, Salmonella에 대한 세균 배양, 염색, 생화학적 특성을 조사하고 그 결과를 기술하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제20권8호
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• pp.1258-1265
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• 2007

Metabolizable energy (ME) required for basal metabolism, activity and growth was considered as the criterion for targeting specific increases in body weight (100 g/week) of broiler chicks during the grower phase (5-20 weeks) and its impact was evaluated on breeder performance. Broiler female chicks (460) from a synthetic dam line were randomly distributed to 4 test groups with 23 replicates of 5 birds each and housed in cages. The first group (ME-100) was offered a calculated amount of ME by providing a measured quantity of grower diet (160 g protein and 2,600 kcal ME/kg) which increased with age and weight gain (133-294 kcal/bird/day). The other three groups were offered 10 or 20% less ME (ME-90 and ME-80, respectively) and 10% excess ME (ME-110) over the control group (ME-100). From 21 weeks of age, a single breeder diet (170 g protein and 2,600 kcal ME/kg) was uniformly fed to all groups and the impact of grower ME restriction on breeder performance evaluated up to 58 weeks. The targeted body weight gain of 1,600 g in a 16-week period was achieved by pullets of the ME-100 group almost one week earlier by gaining 8.7 g more weight per week. However, pullets in the ME-90 group gained 1,571 g during the same period, which was closer to the targeted weight. At 20 weeks of age, the conversion efficiency of feed (5.21-5.37), ME (13.9-14.1 kcal/g weight gain) and protein (0.847-0.871 g/g weight gain), eviscerated meat yield, giblet and tibia weights were not influenced by ME restriction, but the weights of abdominal fat and liver were higher with increased ME intake. Reduction of ME by 10% in the grower period significantly delayed sexual maturity (169.3 d), but increased egg production (152.5 /bird) with better persistency. Improved conversion efficiency of feed, ME and protein per g egg content were also observed in this group up to 56 weeks. The fertility and hatchability at 58 weeks of age were higher in the ME-90 group compared to the control and 10% excess ME feeding. In conclusion, the present study revealed the possibility of achieving targeted weight gain in broiler growers by feeding measured quantities of ME during the rearing period with consequential benefits in breeder performance.

• Asian-Australasian Journal of Animal Sciences
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• 제1권3호
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• pp.173-178
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• 1988

To study the effects of utilizing extruded full fat soybean (FFS) in layer diets, 300 White Leghorn pullets were put in trial divided into 5 treatments; control (commercial soybean meal as protein source), FFS 50% (replacing 50% of soybean meal with FFS), FFS 100% (replacing all amount of soybean meal with FFS), soybean oil and tallow added treatment. Each treatment consisted of 5 replicates of 12 birds. Egg production and feed efficiency from hens fed control diet were significantly lower than from hens fed the other diets. Significant differences in egg production and feed efficiency were found between the control and the other treatments. Cholesterol concentration of serum and egg yolk were not affected by any dietary treatment. Feeding extruded full fat soybean did not cause pancreatic hypertrophy nor change in mortality. There was an indication that linoleic acid (C18:2), linolenic acid (C18:3) and iodine contents increased in the thigh and egg yolk lipid of the groups fed FFS or soybean soybean can serve as effective protein source for layer diets if economically justified.