• 제목/요약/키워드: F-ratio

검색결과 3,555건 처리시간 0.038초

글리콜을 용매로 제조한 연고형 불투명 도재의 물성 (Manufacture of paste opaque porcelains using glycols as a solvent and evaluation of their physical properties)

  • 김사학
    • 대한치과기공학회지
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    • 제25권1호
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    • pp.41-62
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    • 2003
  • In this research, we manufactured the paste opaque porcelains using Propylene Glycol (PG) and Buthylene Glycol (BG) as a solvent, and compared the composition of solvents, the coefficient of thermal expansion, the particle size distribution, the viscosity and bonding strength to metal, and the tone with those of the commercial products(Duceram Plus, Duceram GmbH; VMK 95, Vita Co.; Noritake EX-3, Noritake Co.)used in the clinical field. The results of the research were as follows: 1. The result of solvent analysis indicated that the solvents included in the paste opaque porcelains of the control group were mainly composed of Glycols. 2. From the Coefficient of thermal expansion measurement, we drew out the following results; testing group: $14.0\times10^{-6}/^{\circ}C$, Duceram Plus: $13.9\times10^{-6}/^{\circ}C$, VMK 95: $14.3\times10^{-6}/^{\circ}C$, and Noritake EX-3: $13.3\times10^{-6}/^{\circ}C$. 3. Seen from the result of particle size distribution measurement, the experimental group was similar to the control group in 1$\mu m$ below, but the experimental group marked the highest distribution of 61% in the case of between 1$\mu m$ and 5$\mu m$. Between 5$\mu m$ and 10$\mu m$, they showed relatively similar distribution, and Noritake EX-3 was turned out the highest distribution of 29% in 10$\mu m$ above. 4. From the result of viscosity measurement, Duceram plus showed the highest viscosity throughout all the measurements followed by Noritake Ex-3, experimental group and VMK 95 in decreasing order. 5. The result of bonding strength measurement was EX 35.53 $\beta\acute{A}$, DU 40.88 $\beta\acute{A}$, VM 39.43 $\beta\acute{A}$, and NO 35.39 $\beta\acute{A}$, and no significant difference was found between the experimental group and the control groups(P>0.05). 6. The measurement of the tone indicated that the $L^*$ value of the experimental group was 86.89 0.63 in average, which is higher than the control group in its brightness. In the case of the $a^*$ value, Duceram Plus, VMK 95 and EX-3 showed positive value, whereas the testing group was turned out negative value. In $b^*$ value, Duceram Plus proved the highest. From the results of this research, the paste opaque porcelains using Propylene Glycol (PG) and Buthylene Glycol (BG) as a solvent did not make differences from the commercial products that are actually used in the clinical fields. Therefore, it is possible to utilize Propylene Glycol (PG) and Buthylene Glycol (BG) for the paste opaque porcelains of P.F.M crown. It is also recommended that further researches concerning the compositions and forms of powder, the types of organic solvent components and the ratio of mixture proceeded in order to improve the level of productivity in the future.

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Effects of Phytase and Carbohydrases Supplementation to Diet with a Partial Replacement of Soybean Meal with Rapeseed Meal and Cottonseed Meal on Growth Performance and Nutrient Digestibility of Growing Pigs

  • Shim, Y.H.;Chae, B.J.;Lee, J.H.
    • Asian-Australasian Journal of Animal Sciences
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    • 제16권9호
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    • pp.1339-1347
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    • 2003
  • An experiment was conducted to investigate the effects of microbial phytase ($Natuphos^{(R)}$) supplementation in combination with carbohydrases (composed of enzymes targeted to soybean meal (SBM) dietary components such as $\alpha$-galactosides and galactomannans; $Endo-Power^{(R)}$) to corn-soybean meal based diet (CSD) and complex diet (CD) with a partial replacement of SBM with rape seed meal (RSM) and cotton seed meal (CSM) on growth performance and nutrient digestibility of growing pigs. A total of 168 growing pigs averaging $13.18{\pm}1.77kg$ of initial body weight was arranged as a $2{\times}2$ factorial design with main effects of diet types (corn-SBM based diet (CSD) and complex diets (CD; 5% of SBM was replaced with 2.5% of RSM and 2.5% of CSM in diet for phase I (0 to 3 weeks) and 6% of SBM was replaced with 3% of RSM and 3% of CSM in diet for phase II (4 to 7 weeks))) and enzyme supplementation (none and 0.1% of phytase (500 FTU/kg diet) and 0.1% of carbohydrases). The diet with enzyme application were formulated to have a 0.18% unit lower aP than diets without enzyme application. Each treatment had three replicates with 14 pigs per replicate. To determine supplementation effect of phytase and carbohydrases on ileal amino acid digestibility of SBM, RSM and CSM, a total of 18 T-cannulated pigs (initial body weight; $13.52{\pm}1.24kg$) were assigned to six dietary treatments in the present study. Dietary treatments in metabolic trial included 1) SBM diet, 2) SBM diet+with enzymes (phytase (500 FTU/kg) and carbohydrases at 0.1%, respectively), 3) CSM diet, 4) CSM diet+enzymes, 5) RSM diet and 6) RSM diet+enzymes. During whole experimental period (0 to 7 wks), there was no difference in growth performance between diets (CSD and CD). However, dietary phytase and carbohydrases supplementation significantly improved gain/feed ratio (G:F) of growing pigs. During the phase II (4-7 weeks), dietary phytase and carbohydrases supplementation significantly improved all fecal nutrient digestibilities (Dry matter (DM), gross energy (GE), crude protein (CP), crude fat (CF), calcium (Ca) and phosphorus (P)). Dietary phytase and carbohydrases supplementation improved significantly overall ileal amino acid digestibilities of SBM, RSM and CSM based diets (p<0.05). The simultaneous inclusion of phytase and carbohydrases in both of CSD and CD reduced feed cost per kg body weight gain (FCG). Also, results suggest that 2.5 to 3% of RSM and CSM, respectively, might be used as a protein source in growing pig diets without having an adverse effect on the growth performance and nutrient digestibility and simultaneous phytase and carbohydrases addition improves nutritional value of SBM, RSM and CSM by improving ileal amino acid digestibilities.

Effects of Anti-diarrhoeal Herbs on Growth Performance, Nutrient Digestibility, and Meat Quality in Pigs

  • Cho, J.H.;Zhang, S.;Kim, In-Ho
    • Asian-Australasian Journal of Animal Sciences
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    • 제25권11호
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    • pp.1595-1604
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    • 2012
  • Two studies were conducted to investigate the effects of anti-diarrhoeal herbs on growth performance, nutrient digestibility, and meat quality in pigs. In Exp 1, 150 weanling-growing piglets (average BW = $7.5{\pm}0.24$ kg, average age = $27{\pm}1$ d) were allotted into one of the five dietary treatments, including: i) CON, basal diet, ii) DP, basal diet+1 g/kg date pits, iii) JH, basal diet+0.5 g/kg Japanese-honeysuckle, iv) HCT, basal diet+1 g/kg houttuynia cordata thunb, and v) LE, basal diet+1 g/kg laquer tree extract. From wk 0 to 5, the JH, HCT and LE groups presented higher (p<0.05) ADFI, ADG and gain/feed ratio (G/F) than CON and DP groups. During wk 5 to 10, Pigs fed JH, HCT and LE diets indicated higher (p<0.05) ADG and ADFI than the pigs fed CON and DP diets. During the entire experimental period, a significant increase of ADG appeared in JH, HCT and LE (p<0.05). Pigs fed JH, HCT and LE diets got a higher (p<0.05) ADFI than the pigs fed CON and DP diets. Pigs fed diets with supplementations of herb additives revealled lower (p<0.05) score of diarrhea pigs during d 2 to d 6 compared with pigs fed CON diet. In Exp 2, 60 growing-finishing barrows and gilts (average BW = $54.10{\pm}1.20$ kg, average age = $54{\pm}3$ d) were allotted to three treatments: i) CON, basal diet; ii) YG, basal diet+1 g/kg yellow ginger and iii) HR, basal dietary+1 g/kg hoantchy root, respectively. From wk 0 to 5, Dietary supplementation of YG and HR enhanced (p<0.05) ADG. No difference was found between YG and HR treatments. During, wk 5 to 10, ADG also was observed higher in YG and HR treatments than CON group (p<0.05). Additional, YG had the highest ADG (p<0.05) among treatments. There was always an increase of ADG in YG and HR (p<0.05) through all periods. HR treatment showed a lower (p<0.05) score of diarrhoeal pigs on d 1and d 2 compared with CON treatment. Pigs fed YG and HR diets had a higher (p<0.05) longissimus muscle area (LMA) than pigs fed CON diet. In conclusion, anti-diarrhoeal herbs can improve growth performance, and prevent diarrhea incidence in pigs, it can also increase LMA in finishing pigs.

Forsythia suspensa Extract Has the Potential to Substitute Antibiotic in Broiler Chicken

  • Han, X.;Piao, X.S.;Zhang, H.Y.;Li, P.F.;Yi, J.Q.;Zhang, Q.;Li, P.
    • Asian-Australasian Journal of Animal Sciences
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    • 제25권4호
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    • pp.569-576
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    • 2012
  • Two experiments were conducted to investigate the potential for Forsythia suspensa extract (FSE) to substitute for antibiotic in broiler chicken. First, a well-diffusion assay procedure and a 2-fold dilution method were used to determine the bacteriostatic activity of FSE on Escherichia coli K88, staphylococcus aureus, and salmonella was assayed. An inhibitory effect of FSE was observed on the growth of these bacteria. This effect seems to be dose depended, which disappeared after 25.00, 12.50, 1.56 mg/ml. Second, a 42-d trial with 252 broiler chickens (d 1, $38.7{\pm}1.1$ g BW) was conducted to evaluate the effect of dietary supplementation of FSE in broiler chicken. The feeding program consisted of a starter diet from d 1 to 21 and a finisher diet from d 22 to 42. Dietary treatments included were: i) NC: negative control fed a corn-soybean meal based diet; ii) PC: positive control group fed based diet with chlortetracycline; and iii) FC: a test group fed with 100 mg FSE/kg diet. In this study growth performance did not differ among treatments during the starter period. However, dietary supplemental chlortetracycline and FSE increased (p<0.05) average daily gain (ADG), average daily feed intake (ADFI) compared with NC during the finisher and overall phase. Apparent digestibility of calcium on d 21, digestibility of energy and calcium on d 42 of FC was greater (p<0.05) than NC. Moreover, cecal Escherichia coli counts for birds from FC were lower (p<0.05) than NC. Dietary FSE supplementation also improved (p<0.05) villus height and villus height to crypt depth ratios in both duodenum and ileum and decreased (p<0.05) crypt depth in the duodenum. Duodenum villus height and villus height to crypt depth ratio in both duodenum and ileum from the FC group were also greater (p<0.05). Serum growth hormone and IGF-1 were not influenced by different treatments. Apparently, FSE has the potential to substitute for antibiotic in broiler chicken.

Growth Performance, Meat Quality and Fatty Acid Metabolism Response of Growing Meat Rabbits to Dietary Linoleic Acid

  • Li, R.G.;Wang, X.P.;Wang, C.Y.;Ma, M.W.;Li, F.C.
    • Asian-Australasian Journal of Animal Sciences
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    • 제25권8호
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    • pp.1169-1177
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    • 2012
  • An experiment was conducted to determine the effects of different amounts of dietary linoleic acid (LA) on growth performance, serum biochemical traits, meat quality, fatty acids composition of muscle and liver, acetyl-CoA carboxylase (ACC) and carnitine palmitoyl transferase 1 (CPT 1) mRNA expression in the liver of 9 wks old to 13 wks old growing meat rabbits. One hundred and fifty 9 wks old meat rabbits were allocated to individual cages and randomly divided into five groups. Animals in each group were fed with a diet with the following LA addition concentrations: 0, 3, 6, 9 and 12 g/kg diet (as-fed basis) and LA concentrations were 0.84, 1.21, 1.34, 1.61 and 1.80% in the diet, respectively. The results showed as follows: the dietary LA levels significantly affected muscle color of LL included $a^*$ and $b^*$ of experimental rabbits (p<0.05). The linear effect of LA on serum high density lipoprotein cholesterol was obtained (p = 0.0119). The saturated fatty acids (SFAs) and monounsaturated fatty acids (MUFAs) contents of LL decreased and the polyunsaturated fatty acids (PUFAs) content of LL increased with dietary LA increase (p<0.0001). The PUFA n-6 content and PUFA n-3 content in the LL was significantly affected by the dietary LA levels (p<0.01, p<0.05). The MUFAs content in the liver decreased and the PUFAs contents in the liver increased with dietary LA increase (p<0.0001). The PUFA n-6 content and the PUFA n-6/n-3 ratio in the liver increased and PUFA n-3 content in the liver decreased with dietary LA increase (p<0.01). The linear effect of LA on CPT 1 mRNA expression in the liver was obtained (p = 0.0081). In summary, dietary LA addition had significant effects on liver and muscle fatty acid composition (increased PUFAs) of 9 wks old to 13 wks old growing meat rabbits, but had little effects on growth performance, meat physical traits and mRNA expression of liver relative enzyme of experimental rabbits.

Saccharomyces cerevisiae Live Cells Decreased In vitro Methane Production in Intestinal Content of Pigs

  • Gong, Y.L.;Liao, X.D.;Liang, J.B.;Jahromi, M.F.;Wang, H.;Cao, Z.;Wu, Y.B.
    • Asian-Australasian Journal of Animal Sciences
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    • 제26권6호
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    • pp.856-863
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    • 2013
  • An in vitro gas production technique was used in this study to elucidate the effect of two strains of active live yeast on methane ($CH_4$) production in the large intestinal content of pigs to provide an insight to whether active live yeast could suppress $CH_4$ production in the hindgut of pigs. Treatments used in this study include blank (no substrate and no live yeast cells), control (no live yeast cells) and yeast (YST) supplementation groups (supplemented with live yeast cells, YST1 or YST2). The yeast cultures contained $1.8{\times}10^{10}$ cells per g, which were added at the rates of 0.2 mg and 0.4 mg per ml of the fermented inoculum. Large intestinal contents were collected from 2 Duroc${\times}$Landrace${\times}$Yorkshire pigs, mixed with a phosphate buffer (1:2), and incubated anaerobically at $39^{\circ}C$ for 24 h using 500 mg substrate (dry matter (DM) basis). Total gas and $CH_4$ production decreased (p<0.05) with supplementation of yeast. The methane production reduction potential (MRP) was calculated by assuming net methane concentration for the control as 100%. The MRP of yeast 2 was more than 25%. Compared with the control group, in vitro DM digestibility (IVDMD) and total volatile fatty acids (VFA) concentration increased (p<0.05) in 0.4 mg/ml YST1 and 0.2 mg/ml YST2 supplementation groups. Proportion of propionate, butyrate and valerate increased (p<0.05), but that of acetate decreased (p<0.05), which led to a decreased (p<0.05) acetate: propionate (A: P) ratio in the both YST2 treatments and the 0.4 mg/ml YST 1 supplementation groups. Hydrogen recovery decreased (p<0.05) with yeast supplementation. Quantity of methanogenic archaea per milliliter of inoculum decreased (p<0.05) with yeast supplementation after 24 h of incubation. Our results suggest that live yeast cells suppressed in vitro $CH_4$ production when inoculated into the large intestinal contents of pigs and shifted the fermentation pattern to favor propionate production together with an increased population of acetogenic bacteria, both of which serve as a competitive pathway for the available H2 resulting in the reduction of methanogenic archaea.

The Effect of Level of Crude Protein and Available Lysine on Finishing Pig Performance, Nitrogen Balance and Nutrient Digestibility

  • Ball, M.E.E.;Magowan, E.;McCracken, K.J.;Beattie, V.E.;Bradford, R.;Gordon, F.J.;Robinson, M.J.;Smyth, S.;Henry, W.
    • Asian-Australasian Journal of Animal Sciences
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    • 제26권4호
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    • pp.564-572
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    • 2013
  • Two trials were conducted to investigate the effect of decreasing the crude protein (CP) content of diets for finishing pigs containing two levels of available lysine on nutrient digestibility, nitrogen (N) balance and production performance. Ten finishing diets containing five levels of CP (on average 144, 155, 168, 182 and 193 g/kg fresh basis) and two levels of available lysine (6.9 and 8.2 g/kg fresh basis) were formulated. The diets were offered to pigs on a performance trial (n = 800 Large White (LW)${\times}$Landrace (LR) pigs) from 10 wk of age until finish at 21 wks+5 d of age. Average daily gain (ADG), average daily feed intake (ADFI) and feed conversion ratio (FCR) were calculated. In addition, a digestibility/N balance trial was conducted using pigs (n = 80 $LW{\times}LR$) housed in metabolism crates. Digestibility of dry matter (DM), CP, oil, fibre and energy was determined. N balance values were determined through analysis of N content of urine and faeces ('as determined'). N balance values were also calculated using ADG values and assuming that 16% of growth is protein deposition ("as calculated"). Pig performance was poor between 10 and 13 wk of age which indicated that the dietary treatments were nutritionally inadequate for pigs less than 40 kg. There was a significant (p<0.01) quadratic effect of increasing CP level on feed intake, ADG and FCR from 10 to 13 wk which indicated that the lower CP levels did not supply adequate levels of essential or non-essential amino acids. There was no effect of increasing available lysine level throughout the early period, which in conjunction with the response in older pigs, suggested that both 8.2 and 6.9 g/kg available lysine were insufficient to drive optimum growth. There was a positive response (p<0.05) to increasing available lysine level from 13 wk to finish which indicated that 6.9 g/kg available lysine was not adequate for finishing pigs. Energy digestibility decreased with decreasing CP level of diets containing 6.9 g/kg available lysine which may be attributed to the higher fibre content of the lower CP diets. Nitrogen excretion (g/d) was lowered when dietary CP was reduced regardless of whether the values were determined through balance or calculated using ADG. Calculated N excretion decreased linearly (p<0.001) and quadratically (p<0.001) with decreasing dietary CP content. When the N balance figures calculated in this study were compared with those quoted in the Northern Ireland and English Nitrates Directive Action Programmes, N excretion was less per pig (wean to finish) offered a 169 g/kg CP, 8.2 g/kg available lysine diet (2.39 kg vs 3.41 kg (Northern Ireland) and 2.93 kg (England)).

Cu-Chabazite SCR Catalysts의 황 피독 및 탈황에 의한 NOx 저감 성능에 관한 연구 (A study of NOx performance for Cu-chabazite SCR catalysts by Sulfur poisoning and desulfation)

  • 남정길
    • Journal of Advanced Marine Engineering and Technology
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    • 제37권8호
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    • pp.855-861
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    • 2013
  • 저온에서 NOx 저감률이 높은 작은 기공을 갖는 Cu-chabazite SCR 촉매는 150 에서 $300^{\circ}C$ 범위의 낮은 배기가스 온도를 갖는 박용 디젤엔진에 적용성이 높다. 불행하게도, 박용디젤엔진용 연료는 체적베이스로 1.5% 이상의 높은 레벨의 황을 함유 할 수 있다. 이것은 공연비 50:1로 엔진 운전시에 배기가스에 이산화황의 레벨이 500 ppm에 해당된다. 배기가스에 포함되어 있는 높은 레벨의 이산화황은 Cu-chabazite SCR 촉매의 NOx 저감률을 감소시키는 역할을 할 수 있다. 본 연구에서는 Cu-chabazite SCR촉매의 황 피독에 의한 NOx 저감 성능을 연구하기 위하여 벤치플로 시스템을 구축하였다. Cu-chabazite SCR 촉매를 황 피독 시키기 위하여 5% 이산화탄소, 14% 산소, 5% 물과 나머지 질소로 만들어진 배기가스에 500 ppm의 이산화황을 각각 150, 200, 250, $300^{\circ}C$에서 2시간씩 노출 시켰다. 황 피독후 Cu-chabazite SCR 촉매의 불활성 한계를 측정하기 위하여 저온(150~$300^{\circ}C$)에서 NOx 저감 성능을 평가하였다. 또한, 600 과 $700^{\circ}C$에서 각각 30분씩 탈황 작업을 수행하여, 황 피독된 Cu-chabazite SCR 촉매의 NOx 저감 성능이 회복될 수 있는 온도를 결정하였다.

Effects of Wet Feeding of Processed Diets on Performance, Morphological Changes in the Small Intestine and Nutrient Digestibility in Weaned Pigs

  • Yang, J.S.;Lee, J.H.;Ko, T.G.;Kim, T.B.;Chae, B.J.;Kim, Y.Y.;Han, In K.
    • Asian-Australasian Journal of Animal Sciences
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    • 제14권9호
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    • pp.1308-1315
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    • 2001
  • This study was conducted to evaluate the effects of different methods of feeding and processing of diets on performance, morphological changes in the small intestine and nutrient digestibility of young pigs. A total of 120 pigs (Youkshire${\times}$Landrace${\times}$Duroc; initial body weight of $5.83{\pm}0.67kg$) were randomly allotted into six treatments in a $2{\times}3$ factorial design. Treatments were 1) dry feeding with a mash diet (DM), 2) dry feeding with a pelleted diet (DP), 3) dry feeding with an expanded crumble diet (DEC), 4) wet feeding with a mash diet (WM), 5) wet feeding with a pelleted diet (WP), 6) wet feeding with an expanded crumble diet (WEC). Average daily gain (ADG) and average daily feed intake (ADFI) were not significantly (p>0.05) different among treatments. However, feed conversion ratio (FCR) was significantly improved when pigs fed a pelleted diet or an expanded crumble diet. Pigs fed an expanded crumble diet showed 9.2% and 17.3% improvement in ADG and FCR compared with those fed a mash diet. The morphological changes in the small intestine were examined at the termination (4 weeks after weaning) of the experiment. Differences in morphological changes of gastrointestinal tract were not significant among treatments. Though villus height was not significantly affected by feeding method or feed processing, the villus height of weaned pigs tended to be preserved by wet feeding. The use of a pelleted diet also helped to prevent the shortening of villus height. Pigs fed a WP diet maintained the highest villus height at all parts of the small intestine. There was no significant difference (p>0.05) in nutrient digestibility among treatments. However, nutrient digestibility for pigs fed a pelleted diet had a higher than that of pigs fed mash diets. Especially, pigs fed a WP diet digested 5.3% more P each day than those fed a DM diet. Compared with the mash diet, the expanded crumble diet decreased feed cost per kg weight gain by 15%. The net profit per pig was 79% higher in the expanded crumble diet pigs than in mash diet pigs. In conclusion, this study suggests that feeding processed diets to piglets can be more beneficial in terms of FCR and production cost.

Association of UDP-galactose-4-epimerase with milk protein concentration in the Chinese Holstein population

  • Li, Cong;Cai, Wentao;Liu, Shuli;Zhou, Chenghao;Cao, Mingyue;Yin, Hongwei;Sun, Dongxiao;Zhang, Shengli;Loor, Juan J.
    • Asian-Australasian Journal of Animal Sciences
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    • 제33권11호
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    • pp.1725-1731
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    • 2020
  • Objective: An initial RNA-Sequencing study revealed that UDP-galactose-4-epimerase (GALE) was one of the most promising candidates for milk protein concentration in Chinese Holstein cattle. This enzyme catalyzes the interconversion of UDP-galactose and UDP-glucose, an important step in galactose catabolism. To further validate the genetic effect of GALE on milk protein traits, genetic variations were identified, and genotypes-phenotypes associations were performed. Methods: The entire coding region and the 5'-regulatory region (5'-UTR) of GALE were re-sequenced using pooled DNA of 17 unrelated sires. Association studies for five milk production traits were performed using a mixed linear animal model with a population encompassing 1,027 Chinese Holstein cows. Results: A total of three variants in GALE were identified, including two novel variants (g.2114 A>G and g.2037 G>A) in the 5'-UTR and one previously reported variant (g.3836 G>C) in an intron. All three single nucleotide polymorphisms (SNPs) were associated with milk yield (p<0.0001), fat yield (p = 0.0006 to <0.0001), protein yield (p = 0.0232 to <0.0001) and protein percentage (p<0.0001), while no significant associations were detected between the SNPs and fat percentage. A strong linkage disequilibrium (D' = 0.96 to 1.00) was observed among all three SNPs, and a 5 Kb haplotype block involving three main haplotypes with GAG, AGC, and AGG was formed. The results of haplotype association analyses were consistent with the results of single locus association analysis (p<0.0001). The phenotypic variance ratio above 3.00% was observed for milk protein yield that was explained by SNP-g.3836G >C. Conclusion: Overall, our findings provided new insights into the polymorphic variations in bovine GALE gene and their associations with milk protein concentration. The data indicate their potential uses for marker-assisted breeding or genetic selection schemes.