지속적인 생균제의 첨가가 돼지의 성장, 영양소 이용율 혈중 요소태 질소 및 면역능력에 미치는 영향

길동용,임종선,전경철,김법균,김경수,김유용 한국동물자원과학회 2004 한국축산학회지 Vol.46 No.1

This experiment was conducted to investigate the effect of continuous feeding of probiotics on growth performance, nutrient digestibility, blood urea nitrogen(BUN) and immune responses in pigs. Treatments were 1) Control(basal diet), 2) P-0.1(basal diet + 0.1% probiotics) and 3) P-0.2(basal diet + 0.2% probiotics). In growth trial, a total of sixty pigs(6.17±0.45 ㎏ average body weight) weaned at 21 days of age were used. All pigs were assigned according to sex and body weight, and each treatment had 5 replicates of 4 pigs per pen in a randomized complete block(RCB) design. During 0~8 weeks, there was no significant difference in average daily gain(ADG), average daily feed intake(ADFI) and gain:feed ratio(G/F) among treatments. During 9~20 weeks, ADG was improved significantly in pigs fed P-0.1 or P-0.2 diets when compared to the pig fed control diet(P<0.05), but there was no significant difference in ADFI and G/F ratio. During overall period, ADG, ADFI and G/F ratio were not significantly different among treatments. In the first metabolic trial(17.93±1.45㎏ average body weight), apparent digestibility of DM, protein, fat in pigs fed P-0.1 and P-0.2 diets were greater than in pigs fed control diet(P<0.05) and ash digestibility in pigs fed P-0.2 diet was significantly higher than in pigs fed control diet(P<0.05). Calcium digestibility in pigs fed P-0.2 diet was significantly higher than in pigs fed control and P-0.1 diets(P<0.05). Fecal-N excretion was lower in pigs fed P-0.1 and P-0.2 diets than in pigs fed control(P<0.05). In the second metabolic trial(41.80±2.68㎏ average body weight), there was no significant difference among treatments in apparent digestibility of nutrients and N-retention. In blood assay for the BUN and immune responses investigations, there was no significant difference among treatments during overall period of experiment. Therefore, this experiment suggested that probiotics supplementation could improve growth performance and nutrient digestibility of pigs.

A Phosphate-Binding Pocket within the Platform-PAZ-Connector Helix Cassette of Human Dicer

Tian, Y.,Simanshu, Dhirendra K.,Ma, J.B.,Park, J.E.,Heo, I.,Kim, V.,Patel, Dinshaw J. Cell Press 2014 Molecular cell Vol.53 No.4

We have solved two families of crystal structures of the human Dicer ''platform-PAZ-connector helix'' cassette in complex with small interfering RNAs (siRNAs). The structures possess two adjacently positioned pockets: a 2 nt 3'-overhang-binding pocket within the PAZ domain (3' pocket) and a phosphate-binding pocket within the platform domain (phosphate pocket). One family of complexes contains a knob-like α-helical protrusion, designated ''hDicer-specific helix,'' that separates the two pockets and orients the bound siRNA away from the surface of Dicer, which could be indicative of a product release/transfer state. In the second complex, the helical protrusion is melted/disordered and the bound siRNA is aligned toward the surface of Dicer, suggestive of a cleavage-competent state. These structures allow us to propose that the transition from the cleavage-competent to the postulated product release/transfer state may involve release of the 5'-phosphate from the phosphate pocket while retaining the 3' overhang in the 3' pocket.

Effects of Different Levels of Vitamin-Mineral Premixes on Growth Performance, Nutrient Digestibility, Carcass Characteristics and Meat Quality of Growing-Finishing Pigs

Tian, J.Z.,Lee, J.H.,Kim, J.D.,Han, Y.K.,Park, K.M.,Han, In K. Asian Australasian Association of Animal Productio 2001 Animal Bioscience Vol.14 No.4

Two experiments using growing and finishing pigs (Landrace$\times$Duroc$\times$Yorkshire) were conducted to determine the effects of different levels of vitamins and trace minerals (VTM) on growth performance, nutrient digestibility, carcass characteristics and meat quality of growing-finishing pigs, and to evaluate the suitability of vitamin-mineral levels commonly used in the swine industry in Korea. A total of 120 three crossbred (Landrace$\times$Duroc$\times$Yorkshire) growing (Experiment I: 20.90 0.44 kg average initial body weight) and finishing (Experiment II: 53.55 0.97 kg average initial body weight) were used in 6 and 9 weeks feeding trials, respectively. Pigs were allotted on the basis of sex and weight to 5 treatments with 6 replications per treatment with 4 pigs per pen in a completely randomized block design. Treatments were: 1) control, 2) fat soluble vitamin 200% vs. control, 3) water soluble vitamin 200% vs. control, 4) trace mineral 50% vs. control, 5) trace mineral 200% vs. control. In experiment I, during the overall experimental period (0 to 6 weeks, 21 to 54 kg body weight), ADG of the 200% trace mineral supplemented group was significantly higher than that of the 50% trace mineral supplemented group. There were no significant differences among other the treatments. Digestibility of crude protein was lowest in mineral 50% supplemented group (p<0.05). Calcium digestibility was significantly higher in the 200% fat soluble vitamin supplemented group than in the other treatments (p<0.05). In experiment II, during the overall experimental period (0 to 9 weeks, 54 to 106 kg body weight), growth performance was not significantly affected by dietary vitamin and trace mineral levels. However, increasing level of water soluble vitamins at the level of 200% compared to control had a tendency to improve the overall growth performance. Overall carcass characteristics except for carcass length did not differ among pigs fed the dietary treatments. Loin eye area, pH, drip loss and shear force of meat were not affected by dietary vitamin and trace mineral levels. There was a trend for less fat content (%) in pork when the level of vitamin and trace mineral was increased, but the difference was not significant. Flavor score was the lowest in control and highest in the 200% fat soluble vitamin supplemented group (p<0.05). Juiciness of muscle was lower in the 200% fat soluble vitamin supplemented group than other dietary treatments, except for trace mineral 50% supplemented group (p<0.05). Based on these results, it is suggested that "typical" commercial levels of vitamin and trace minerals used by feed companies in Korea are sufficient to meet requirement for the maximum growth of growing-finishing pigs. Our results suggests that a reduction in trace mineral levels in commercial diets could be considered to reduce feed cost and nutrient excretion with economic and environmental benefits.

Effects of Dietary Selenium Supplementation on Growth Performance, Selenium Retention in Tissues and Nutrient Digestibility in Growing-finishing Pigs

Tian, J.Z.,Yun, M.S.,Ju, W.S.,Long, H.F.,Kim, J.H.,Kil, D.Y.,Chang, J.S.,Cho, S.B.,Kim, Y.Y.,Han, In K. Asian Australasian Association of Animal Productio 2006 Animal Bioscience Vol.19 No.1

This experiment was conducted to investigate the effects of selenium (Se) sources and levels on growth performance, nutrient digestibility and Se retention in growing-finishing pigs. A total of 56 crossbred pigs ([$Landrace{\times}Yorkshire$]${\times}$Large White) with average $28.5{\pm}0.2kg$ BW were allotted to 7 treatments on the basis of sex and weight in two replicates and four pigs per pen. A $2{\times}3$ factorial arrangement of treatments was used in a randomized complete block (RCB) design. Two sources of Se (selenite Se or Se-enriched yeast) were added at 0.1, 0.3 and 0.5 mg/kg to each treatment diet. A basal diet without Se supplementation was the seventh treatment group. Three pigs per treatment were randomly selected and samples of loin, liver, pancreas and a kidney were collected, frozen and later analyzed for Se. The digestibility trial was conducted to evaluate the apparent absorption and retention of Se and availability of other nutrients. Growth performance was not affected by dietary sources and levels of Se. No growth retardation was observed in the 0.5 mg/kg dietary Se treatment group regardless of Se sources. The Se concentration of serum in Se supplemented groups was increased compared with the control group (p<0.01). During the growing and finishing phase, Se in serum was clearly increased when organic Se was provided (p<0.01). Interaction of Se source ${\times}$ Se level was observed in Se concentration of loin, liver and pancreas of the pigs at the end of experiment. Selenium retention in the liver, kidney, pancreas and loin of pigs was increased as dietary Se level increased and was higher when pigs were fed organic Se resulting in an interaction response (p<0.01). Nutrient digestibilities were not affected by dietary Se sources or levels. No dietary Se source ${\times}$ Se level interaction was observed in nutrient digestibility. The results from this experiment indicated that dietary Se sources and levels affected the distribution of Se in the body of growing-finishing pigs. Organic source of Se, such as Se-enriched yeast resulted in higher serum and tissue Se concentration compared to inorganic form, while no beneficial effects on nutrient digestibility were observed from dietary Se supplementation in growing-finishing pigs.

Effects of Different Products and Levels of Selenium on Growth, Nutrient Digestibility and Selenium Retention of Growing-finishing Pigs

Tian, J.Z.,Yun, M.S.,Kong, C.S.,Piao, L.G.,Long, H.F.,Kim, J.H.,Lee, J.H.,Lim, J.S.,Kim, C.H.,Kim, Y.Y.,Han, In K. Asian Australasian Association of Animal Productio 2006 Animal Bioscience Vol.19 No.1

This experiment was conducted to evaluate the effects of different selenium (Se) products (inorganic, organic A, organic B) added at two supplemental dietary Se levels (0.1 and 0.3 mg/kg) on growth performance, nutrient digestibility and Se retention in growing-finishing pigs. A $3{\times}2$ factorial arrangement of treatments was used in a RCB design, with a non-Se-fortified basal diet serving as the negative control. A total of 56 crossbred pigs (28 male and 28 female pigs) initially weighing an average $28.45{\pm}0.53kg$ BW were allotted to each treatment with four pigs per pen on the basis of sex and weight. Two pigs per pen were selected and bled from the anterior vena cava at 3- weekly intervals to analyze Se concentration. In the growing phase (0-6 weeks), increased ADFI was observed when pigs were fed organic Se compared to those fed the control diet or inorganic Se treatment (p<0.05). Pigs fed inorganic Se had a great ADFI than pigs fed organic Se (p<0.05) in the late finishing phase (7-12 weeks), although there were no differences in whole period ADFI between organic or inorganic Se products. During 12 weeks of the whole experimental period, serum Se concentration increased linearly when dietary Se level increased regardless of Se products (p<0.05). Both dietary Se source (p<0.05) and Se level (p<0.01) influenced the Se concentration of various pig tissues at end of this experiment and Se content was the highest in the kidney. For the determination of nutrient digestibility, a metabolic trial was conducted in 3 replicates in randomized complete block (RCB) design. A total of 21 barrows ($50.21{\pm}0.62kg$ of average BW) were used in the metabolic study. Selenium supplementation had no effect on nutrient digestibility except for crude protein. Crude protein digestibility increased with dietary supplementation of organic Se (A) compared with other forms of Se products or control diet (p<0.05). Consequently, this experiment indicated that dietary Se products and levels had no effect on growth performance of pigs. Se concentration in tissues and serum was increased in proportion to dietary Se level, especially when organic Se was provided. Although pigs were fed organic forms of Se, bioavailability of organic forms varied among products, consequently bioactivity of organic products to the animals should be evaluated before practical application in animal feed.

Unambiguous Evidence for Existence of Antiferromagnetic Interlayer Coupling in Pt/Co Multilayers with Perpendicular Anisotropy

Z.Y. Liu,F. Zhang,N. Li,B. Xu,D.L. Yu,J.L. He,Y.J. Tian 한국자기학회 2008 한국자기학회 학술연구발표회 논문개요집 Vol.- No.-

Effects of Sex and Market Weight on Performance, Carcass haracteristics and Pork Quality of Market Hogs

Piao, J.R.,Tian, J.Z.,Kim, B.G.,Choi, Y.I.,Kim, Y.Y.,Han, In K. Asian Australasian Association of Animal Productio 2004 Animal Bioscience Vol.17 No.10

An experiment was conducted to examine the effects of sex and market weight on performance, carcass characteristics and pork quality. A total of 224 crossbred pigs (initially 26.64 kg BW) were allotted in a $2{\times}4$ factorial arrangement in a randomized complete block (RCB) design. The variables were sex (gilts and barrows) and different market weights (100, 110, 120 and 130 kg). Average daily gain (ADG) and average daily feed intake (ADFI) were significantly higher (p<0.01) in barrows than gilts, ADFI and feed conversion ratio (FCR) increased as body weight increased (p<0.05). Gender differences were observed in carcass characteristics. Backfat thickness and drip loss were greater in barrows (p<0.01), while loin eye area (p<0.01), flavor score (p<0.05) and lean content (p<0.001) were higher in gilts. Carcass grade and water holding capacity were the highest in 110 kg market weight pigs. The 100 kg arket weight pigs showed lower juiciness, tenderness, shear forces and total palatability than the other market weights (p<0.01). Hunter values (L*, a* and b*) were increased as market weight increased (p<0.05). Hunter a* value was greater in gilts (p<0.01) but L* value and b* value were not affected by sex of pigs. Net profit [(carcass weight${\times}$price by carcass grade)-(total feed cost+cost of purchased pig)] was higher in gilts than barrows (p<0.01), and was higher (p<0.05) in the pigs marketed at 110 and 120 kg market weight compared with 100 kg market weight. These results demonstrated that gilts showed higher carcass characteristics, pork quality, feed cost per kg body weight gain and net profit compared with barrows. Moreover, 110 or 120 kg body weight would be the recommended market weight based on pork quality and net profit for swine producers.

<i>DLEC1</i> is a functional 3p22.3 tumour suppressor silenced by promoter CpG methylation in colon and gastric cancers

Ying, J,Poon, F F,Yu, J,Geng, H,Wong, A H Y,Qiu, G-H,Goh, H K,Rha, S Y,Tian, L,Chan, A T C,Sung, J J Y,Tao, Q Nature Publishing Group 2009 The British journal of cancer Vol.100 No.4

<P>Promoter CpG methylation of tumour suppressor genes (TSGs) is an epigenetic biomarker for TSG identification and molecular diagnosis. We screened genome wide for novel methylated genes through methylation subtraction of a genetic demethylation model of colon cancer (double knockout of <I>DNMT1</I> and <I>DNMT3B</I> in HCT116) and identified <I>DLEC1</I> (Deleted in lung and oesophageal cancer 1), a major 3p22.3 TSG, as one of the methylated targets. We further found that <I>DLEC1</I> was downregulated or silenced in most colorectal and gastric cell lines due to promoter methylation, whereas broadly expressed in normal tissues including colon and stomach, and unmethylated in expressing cell lines and immortalised normal colon epithelial cells. <I>DLEC1</I> expression was reactivated through pharmacologic or genetic demethylation, indicating a DNMT1/DNMT3B-mediated methylation silencing. Aberrant methylation was further detected in primary colorectal (10 out of 34, 29%) and gastric tumours (30 out of 89, 34%), but seldom in paired normal colon (0 out of 17) and gastric (1 out of 20, 5%) samples. No correlation between <I>DLEC1</I> methylation and clinical parameters of gastric cancers was found. Ectopic expression of <I>DLEC1</I> in silenced HCT116 and MKN45 cells strongly inhibited their clonogenicity. Thus, <I>DLEC1</I> is a functional tumour suppressor, being frequently silenced by epigenetic mechanism in gastrointestinal tumours.</P>

Biasing Effect on the Magnetization Reversal of Co Layers in the Co(4 Å)/Pt(28 Å)/Co(4 Å)/CoO(10 Å) Multilayers

Z.Y. Liu,F.S. Wen,L. Li,F. Zhang,J. Y. Xiang,Y.J. Tian 한국자기학회 2010 한국자기학회 학술연구발표회 논문개요집 Vol.2010 No.12

A study on the dynamic characteristics of the secondary loop in nuclear power plant

Zhang, J.,Yin, S.S.,Chen, L.,Ma, Y.C.,Wang, M.J.,Fu, H.,Wu, Y.W.,Tian, W.X.,Qiu, S.Z.,Su, G.H. Korean Nuclear Society 2021 Nuclear Engineering and Technology Vol.53 No.5

To obtain the dynamic characteristics of reactor secondary circuit under transient conditions, the system analysis program was developed in this study, where dynamic models of secondary circuit were established. The heat transfer process and the mechanical energy transfer process are modularized. Models of main equipment were built, including main turbine, condenser, steam pipe and feedwater system. The established models were verified by design value. The simulation of the secondary circuit system was conducted based on the verified models. The system response and characteristics were investigated based on the parameter transients under emergency shutdown and overload. Various operating conditions like turbine emergency shutdown and overspeed, condenser high water level, ejector failures were studied. The secondary circuit system ensures sufficient design margin to withstand the pressure and flow fluctuations. The adjustment of exhaust valve group could maintain the system pressure within a safe range, at the expense of steam quality. The condenser could rapidly take out most heat to avoid overpressure.