• Title/Summary/Keyword: Growth promoters

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Absorption of Carbon Dioxide into Aqueous Potassium Salt of Serine (Serine 칼륨염 수용액의 이산화탄소 흡수특성)

  • Song, Ho-Jun;Lee, Seung-Moon;Lee, Joon-Ho;Park, Jin-Won;Jang, Kyung-Ryong;Shim, Jae-Goo;Kim, Jun-Han
    • Journal of Korean Society of Environmental Engineers
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    • v.31 no.7
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    • pp.505-514
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    • 2009
  • Aqueous potassium salt of serine was proposed as an alternative $CO_2$ absorbent to monoethanolamine (MEA) and its $CO_2$ absorption characteristics were studied. The experiment has been conducted using screening test equipment with NDIR type gas analyzer and vapor-liquid equilibrium apparatus. $CO_2$ absorption/desorption rate and net amount of $CO_2$ absorbed in cyclic process are the criteria to assess the $CO_2$ absorption characteristics in this study. Effective $CO_2$ loading of potassium salt of serine and MEA are 0.425 and 0.230 respectively. Cyclic capacities are 0.354 and 0.298 for potassium salt of serine and MEA. The absorption rate of the potassium serinate decreased sharply at $CO_2$ loading is 0.1 and were maintained approximately at half of MEA. To enhance the absorption rate of aqueous potassium salt of serine, small quantities of rate promoters, namely piperazine and tetraethylenepentamine were blended, so that rich $CO_2$ loading were increased by 13.7% and 18.7% respectively. The rich $CO_2$ loading of potassium salt of serine was 29.2% and 35.0% higher than those of aqueous sodium and lithium salt of serine, respectively. The absorption rate of potassium salt of valine and isoleucine which have similar molecular structures to serine were lower than that of serine because of the presence of bulky side group. Precipitation phenomena during $CO_2$ absorption were discussed by the aid of literatures.

Strategy to Improve the Productivity of Broilers: Focusing on Pre-Starter Diet (초이사료 배합설계를 통한 육계 생산성 증대방안)

  • Nam, Doo Seok;Lee, Jinyoung;Kong, Changsu
    • Korean Journal of Poultry Science
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    • v.42 no.3
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    • pp.247-256
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    • 2015
  • There are approximately 1,500 broiler farms in Korea, each raising 55,000 birds. Ninety-five percent of the farms are contracted with Integration Company. According to the Korean broiler performance index, broilers in Korea are marketed at 32 days with 1.52 kg of body weight. In contrast, the market age and body weight of broilers are 47 days/2.8 kg in the United States and 42 days/2.5 kg in Europe. Because of the younger market age of the Korean broiler, the pre-starter feed is important. Chicks exhibit poor absorption of dietary nutrients up to 7 days after hatching due to an immature digestive system and low enzyme secretion rate and activity. At the beginning of hatching, chicks obtain their nutrients from the egg yolk sac. It is highly recommended that chicks, after consuming the nutrients in the egg yolk sac, are given supplemented pre-starter feed to increase early growth rates and improve the performance of broiler production. Pre-starter nutrient requirements are not expressed in NRC, so Korean feeding standards for poultry and commercial breeding companies determine the nutrient requirements of pre-starter broiler chickens. Three approaches are followed to formulate specially designed pre-starter feeds for broiler chicks: (i) selective use of raw materials, (ii) proper standards of nutrient supply, and (iii) application of feed additives such as exogenous enzymes. In the selection of raw materials, those with high digestibility can be used. The absorption rate of carbohydrates in grains can be increased through feed processing at high temperature and high pressure. Soy proteins and fish meal can also be added as protein sources. As an energy source, vegetable oils are preferred over animal fats because of the former's high digestibility. It is suggested that the levels of proteins and amino acids are higher in pre-starter feed than in starter feed. With regard to energy, the sources of energy are more important than the levels of energy in feed. Feed additives such as exogenous enzymes can be used to improve nutrient digestibility. In addition, organic acids and plant extracts can be used as alternatives to animal growth promoters to stimulate immunity and prevent diseases. The growth performance of broilers is affected by various factors, such as management and disease control, in addition to the nutritional strategy; however, nutritional strategies play an important role in improving the productivity of broilers. Therefore, nutritional strategies, along with management and disease control, are required for improving the productivity of broilers in Korea.

Effects of Feed Supplementations for Fermented Apple Pomace and Cinnamon on Egg Quality and Performance in Laying Hens (산란계 사료 내 사과박 발효물 및 계피의 첨가 · 급여가 생산성 및 계란 품질에 미치는 영향)

  • Kang, Hwan-Ku;Seo, Ok-Suk;Choi, Hee-Chul;Chae, Hyun-Seok;Na, Jae-Cheon;Yu, Dong-Jo;Kang, Guen-Ho;Bang, Han-Tae;Park, Sung-Bok;Kim, Min-Ji;Lee, Ji-Eun;Kim, Dong-Wook;Kim, Sang-Ho
    • Korean Journal of Poultry Science
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    • v.37 no.1
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    • pp.63-68
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    • 2010
  • This experiment was conducted to investigate the effects of dietary supplementation of fermented apple pomace (FAP) and cinnamon on laying performance, egg quality and blood characteristics in laying hens. A total of two hundred 57-wk-old Hy-Line laying hens were divided into five groups with 4 replicates of 10 birds each; control, 0.1% probiotics, 1.0% fermented apple pomace 1.0%, 0.1% cinnamon and 1.0% fermented apple pomace with 1.0% cinnamon. Chickens fed the diets containing 1.0% of fermented apple pomace showed higher egg production than the chickens fed the other diets. No synergic effect on laying performance was found when fermented apple pomace and cinnamon were added to the diets in laying hens. There was no significant major differences in egg quality and serum blood biochemical profiles. These results suggest the possibility that fermentation of apple pomace could be used as the alternative of antibiotic growth promoters.