• Animal Bioscience
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• 제35권9호
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• pp.1390-1399
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• 2022

Objective: The objective of this study was to evaluate the effects of dietary supplementation of Schizosaccharomyces pombe (S. pombe) -expressed phytase on growth performance, apparent ileal digestibility, organ indexes, meat quality, toe ash, and footpad lesions score in broiler chicks. Methods: A total of 390 one-day-old broiler chicks were randomly assigned to 5 groups based on the initial body weight (42.15±0.17 g), there were 6 replicate cages per treatment and 13 birds (mixed sex) per cage. The experimental period was 45 days, including 4 periods (starter, days 1 to 10; grower, days 11 to 24; finisher 1, days 25 to 38; finisher 2, days 39 to 45). Dietary treatments were based on a corn-soybean meal-basal diet and supplemented with 500, 750, 1,000, and 1,500 FTU/kg S. pombe-expressed phytase. One phytase unit (FTU) was defined as the amount of enzyme that catalyzes the release of one micromole phosphate from phytate per minute at 37℃ and pH 5.5. Results: The inclusion of increasing levels of phytase in the diet linearly increased the body weight gain during days 1 to 10 (p = 0.001), 25 to 38 (p = 0.016), 39 to 45 (p = 0.018), and 1 to 45 (p = 0.004), feed intake during days 25 to 38 (p = 0.032), feed conversion ratio during days 1 to 10 (p = 0.001), 39 to 45 (p = 0.038), and 1 to 45 (p = 0.012), carcass weight (p = 0.035), toe ash (p<0.001), and apparent ileal phosphorus digestibility (p = 0.049). However, the footpad lesions score (p = 0.040) decreased linearly with the increase in phytase levels in the diet. Conclusion: Dietary supplementation of S. pombe-expressed phytase was beneficial to the growth performance, toe ash, apparent ileal phosphorus digestibility, and footpad lesions of broiler chicks in a dose-dependent manner.

• 한국농공학회논문집
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• 제53권2호
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• pp.61-65
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• 2011

Biomass is considered to be a major potential fuel and renewable resource for the future. In fact, there is high potential to produce the large amount of energy from biomass around the world. In this study, to obtain basic data for practical application of agricultural and forest by-products as fuel of heating system in agriculture, agricultural and forest biomass resources were surveyed, the pelletizer with capacity of $50\;kg{\cdot}h^{-1}$ was designed and manufactured and pellets were made by the pelletizer. High heating value, ash content, etc. of pellets made of agricultural and forest by-products were estimated. Straw of rice was the largest agricultural biomass in 2009 and the total amount of rice straw converted into energy of $299{\times}10^3$ TOE. And in 2009, amount of forest by-product converted into energy of $9,579{\times}10^3$ TOE. High heating values of pellets made of stem and seed of rape, stem of oat, rice straw and rice husk were 16,034, 16,026, 16,089, 15,650, $15,044\;kJ{\cdot}kg^{-1}$ respectively. High heating values of pellets made of agricultural by-products were average 83.6% compared to that of wood pellet. Average bulk density of pellets made of stem and seed of rape, stem of oat, rice straw and rice husk was $1,400\;kg{\cdot}m^{-3}$ ($1.4\;g{\cdot}cm^{-3}$). Ash contents of the pellets were 6.6, 7, 6.2, 5.5, 33% respectively. Rice husk pellet produced the largest ash content compared to other kinds of pellets.

• 한국세라믹학회지
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• 제39권3호
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• pp.259-264
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• 2002

본 연구에서는 석탄회로 제조된 인공경량골재에 석회석을 첨가하였을 때 소성온도 및 시간에 따른 소성특성을 관찰하였다. 소성온도의 증가에 따라 quartz($SiO_2$)가 감소한 반면 mullite($3Al_2O_3{\cdot}2SiO_2$)가 증가되었으며, 석회석의 첨가에 의해 clinoptiolite와 pagioclase와 같은 소성에 의한 소성광물이 생성되었다. 석탄회 및 석회석으로 제조된 경량골재의 소성성은 주로 소성시간보다는 소성온도에 의해서 좌우되는 것으로 확인되었다. 또한 소성온도 및 시간의 증가는 골재내 형성된 거대기공의 미세화 및 폐기공의 형성으로 전체 기공부피를 축소시키는 경향을 나타냈다. 1000$^{\circ}$C에서 5분가 소성시킨 경량골재의 표면은 용융 슬래그 층의 융착현상에 의해 개기공이 거의 없었으나 내부는 발포가스에 의해 수 ${\mu}$의 미세기공이 폐기공 형태로 균일하게 분포하였다. 이로부터 석회석이 첨가된 소성 경량골재의 적정 소성조건은 소성온도는 약 1000$^{\circ}$C, 소성시간은 5분이 바람직한 것으로 나타났다.

• Asian-Australasian Journal of Animal Sciences
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• 제20권7호
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• pp.1100-1107
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• 2007

The effects of offering broilers phosphorus-adequate diets containing 10.0 and 11.8 g/kg lysine, without and with 500 FTU/kg exogenous phytase, on growth performance and nutrient utilisation were determined. Each of the four experimental diets was offered to 6 replicates of 10 birds from 7 to 28 days of age. Effects of treatment on performance, apparent metabolisable energy, apparent ileal digestibility of amino acids and bone mineralisation were examined. Both additional lysine and phytase supplementation improved (p<0.05) weight gain and feed efficiency, with interactions (p<0.05), as phytase responses were more pronounced in lysine-deficient diets. Phytase improved (p<0.05) apparent metabolisable energy, which was independent of the dietary lysine status. Bone mineralisation, as determined by percentage toe ash, was not affected by treatment, which confirms the phosphorus-adequate status of the diets. Phytase increased (p<0.05) the apparent ileal digestibility of the sixteen amino acids assessed. Unexpectedly, however, the dietary addition of 1.8 g/kg lysine, as lysine monohydrochloride, increased (p<0.05) the ileal digestibility of lysine per se and also that of isoleucine, methionine, phenylalanine, valine, aspartic acid, glutamic acid and tyrosine. In addition, there were significant interactions (p<0.05) between additional lysine and phytase supplementation for arginine, lysine, phenylalanine, aspartic acid, glutamic acid, glycine and serine digestibilities, with the effects of phytase being more pronounced in lysine-deficient diets. The possible mechanisms underlying the increases in amino acid digestibility in response to additional lysine and the interactions between lysine and microbial phytase in this regard are discussed. Also, consideration is given to the way in which phytate and phytase may influence ileal digestibility of amino acids.