• Asian-Australasian Journal of Animal Sciences
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• v.16 no.8
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• pp.1158-1164
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• 2003

In two feeding experiments male and mixed-sex broiler chicks were offered diets based on sorghum and a wheatsorghum blend with two tiers of nutrient specifications, without and with microbial phytase (600 and 800 FTU/kg), from 7-25 and 1-42 days post-hatch, respectively. The nutrient specifications for protein, amino acids, energy density and phosphorus (P) of standard diets were reduced to formulate the modified diets on a least-cost basis. Calculated differences in nutrient specifications between standard and modified diets ranged from 14.3 to 17.1 g/kg crude protein, 0.24 to 0.40 MJ/kg apparent metabolisable energy (AME) and 1.06 to 1.20 g/kg available P. In both experiments, reduced nutrient specifications had a negative impact on growth rates and feed efficiency and phytase supplementation had a positive influence on growth performance and protein efficiency ratios (PER). Phytase addition to the less expensive, modified diets either partially or entirely compensated for reduced growth performance and, consequently, feed costs per kg of live weight gain were reduced. In Experiment 1, phytase increased (p<0.001) nitrogen-corrected AME (AMEn) from 15.39 to 15.89 MJ/kg dry matter. For nitrogen (N) retention there was an interaction (p<0.05) between diet type and phytase as the effects of phytase on N retention were more pronounced in the modified diets, with an increase from 0.512 to 0.561. These results demonstrate the positive effects of phytase on protein and energy utilisation, in addition to its established liberation of phytate-bound P and illustrate the feasibility of assigning nutrient replacement values to the feed enzyme for consideration in least-cost ration formulations. Further work is, however, required to define the most appropriate reductions in nutrient specifications in association with phytase supplementation.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.8
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• pp.1230-1237
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• 2018

Objective: The present study was undertaken to determine an optimal balance between the amount of physically effective neutral detergent fiber (peNDF) to metabolizable glucose (MG) on rumen fermentation, blood metabolites and growth performance of 8 to 10-month-old heifers. Methods: A total of 15 healthy Holstein heifers weighing an average of 256 kg (8 month of age) were randomly assigned to three groups of five. Treatment diets consisted of the following three $peNDF_{8.0}/MG$ levels: 1.46 (Treatment A), 1.74 (Treatment B), and 2.08 (Treatment C). Results: The results showed that the ratio of $peNDF_{8.0}/MG$ affected rumen fermentation, blood metabolites and growth performance of heifers. The average daily gain of heifers tended to decrease as the ratio of $peNDF_{8.0}/MG$ increased (p = 0.07). The concentrations of blood urea nitrogen, triglyceride, and cholesterol increased significantly (p<0.05), while the high-density lipoprotein concentration decreased (p<0.05). After feeding 2 h and 4 h, insulin concentration in Treatment A was greater than Treatment C (p<0.05). Propionate concentration had decreasing trend (p = 0.07); acetate to propionate ratio and non-glucogenic to glucogenic volatile fatty acid (NGR) increased significantly (p<0.05). In addition, the digestibility of dry matter, crude protein, neutral detergent fiber, and acid detergent fiber decreased significantly (p<0.05). Conclusion: The present investigation indicated that dietary $peNDF_{8.0}/MG$ ratio can affect the growth and development, blood metabolites, rumen fermentation and apparent digestibility of heifers, and the optimal dietary $peNDF_{8.0}/MG$ ratio for 8 to 10-month-old heifers in the present study was 1.46.

• Mycobiology
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• v.36 no.2
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• pp.81-87
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• 2008

The optimal conditions for mycelial growth of Phellinus linteus ATCC 26710 were determined to be a log length of 20 cm, temperature of $30^{\circ}C$ and pH of 6.0. Mycelial growth was excellent on the mushroom complete medium, and was optimal when sucrose, man nose and glucose were supplied as carbon sources. Potassium nitrate and sodium nitrate as nitrogen sources supported good mycelial growth. To evaluate P. linteus mycelial colonization on logs, sterilized short log inoculation, drilling inoculation and log-end sandwich inoculation techniques were used. Only sterilized short log inoculation produced good mycelial colonization. Initial mycelial growth and full mycelial colonization were best on 20 cm logs having 42% moisture content. The initial mycelial growth of P. linteus was accelerated over 12hr of sterilization. Basidiocarp formation was optimal using a burying method of logs after $5{\sim}6$ months, and fruiting body formation was superior in cultivation house conditions of $31{\sim}35^{\circ}C$ and in excess of 96% relative humidity.

• Journal of Environmental Science International
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• v.27 no.10
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• pp.933-936
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• 2018

An experiment was conducted to evaluate the efficacy of a mixture of bentonite and illite as feed additives on the growth performance and litter quality of 90 Pekin ducks. The ducks were individually weighed and randomly divided into two treatments (control and 1% combination of silicate minerals), with three replicate pens per treatment, and 15 ducks per pen. Growth performance was not significantly affected (p>0.05) by the combination of bentonite and illite, but a trend of increased growth performance was observed in the control groups. Total nitrogen content and pH in the litter decreased following supplementation with the combination of bentonite and illite (p<0.05) when compared with the control group. This data indicates that the dietary supplementation with the combination of bentonite and illite (1% level) has no positive effect on the growth performance and litter quality of Pekin ducks.

• KSBB Journal
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• v.10 no.2
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• pp.176-182
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• 1995

The environmental and physiological factors affecting the production of exopolysaccharide (Methylan) and Poly-${\beta}$-hydroxybutyrate(PHB) by Methylobacterium organophilum were investigated. The maximum PHB content was obtained at $38^{\circ}C$ whereas maximum polysaccharide concentration was $3.54g/\ell$ at $30^{\circ}C$. Optimum pH was pH 7-8 for PHB production and pH 6-7 for polysaccharide production, respectively. Under the condition of $Mo^{2+}, Mg^{2+} or Mn^{2+}$ limitation with nitrogenlimitation, the PHB accumulation was increased, whereas the polysaccharide production was decreased as compared with that of solenitrogenlimitation. Under the condition of sole K+ limitation, cell growth was significantly inhibited and no polysaccharide was produced. However, the PHB content was as high as 60% of dry cell weight. Effect of C/N ratios (methanol/ammonium) in the feeding solution was examined for the simultaneous production of polysaccharide and PHB. The higher ratio of C/N showed the lower cell growth, higher content of PHB in cells, and higher yield of polysaccharide.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.8
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• pp.1150-1156
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• 2014

This trail was conducted to study the effect of L-proline on the growth performance, and blood parameter in the weaned lipopolysaccharide (LPS)-challenged pigs. Thirty six pigs ($9.13{\pm}0.85$ kg) were assigned randomly to dietary treatments in a $2{\times}3$ factorial arrangement in a 20-d growth assay. Factors were intraperitoneal injection with saline or LPS, and three dietary L-proline supplement levels (0%, 0.5%, or 1.0%). On d 10, blood samples were collected at 3 h after LPS (100 ${\mu}g$ LPS/kg body weight [BW]) or saline injection. On d 20 of the trial, all pigs were orally administrated D-xylose (0.1 g/kg BW) at 2 h, and blood samples were collected at 3 h after LPS or saline injection. As a result, dietary supplementation with 0.5% proline had a tendency to increase average daily gain (ADG) in piglets during d 10 to 20 (p = 0.088). Without LPS challenge, dietary supplementation with 1.0% proline had no effect on growth hormone (GH) concentrations on d 10 (p>0.05), but decreased it after LPS challenge (p<0.05). There was LPS challenge${\times}$proline interaction for GH concentrations on d 10 (p<0.05). Dietary supplementation with 1.0% proline decreased glucagon concentration on d 10 after LPS challenge (p<0.05). In addition, dietary supplementation with proline increased superoxide dismutase (SOD) activity significantly on d 10 and 20 (p<0.05), and 1.0% proline increased heat shock proteins-70 concentration on d 10 (p<0.05). Moreover, proline supplementation increased diamine oxidase (DAO) concentrations after LPS challenge (p<0.05). There was LPS challenge${\times}$proline interaction for DAO (p<0.05). Furthermore, dietary supplementation with 1.0% proline increased the D-xylose level when no LPS challenge (p<0.05). These results indicate that proline supplementation could improve growth performance, increase SOD activities, and has a positive effect on the gastrointestinal tract digestibility in early weaned pigs.

• Journal of Mushroom
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• v.3 no.2
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• pp.45-51
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• 2005

This study was carried out to obtain the basic data on artificial culture of Sparassis crispa. The mycelial growth and density were good in the PBA, PDA and PDM media, and especially prominent in the PBA medium. The optimum condition for the mycelial growth was $25^{\circ}C$ and pH 5.0, respectively. The carbon sources such as glucose, fructose, mannose, xylose(monosaccharide) and maltose(disaccharide) were favorable to mycelial growth of S crispa. The optimal concentration of glucose is 1.0~1.5%. As nitrogen sources, threonine, peptone, glycine, glutamine and valine appeared to be favorable to the mycelial growth and density. The optimal concentration of peptone is 0.3%.

• Korean Journal of Plant Resources
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• v.27 no.1
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• pp.43-50
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• 2014

This study was carried out to determine the optimal medium composition and growth regulators for the micropropagation of Platycodon grandiflorum (Jacq.) A. DC. Nodes containing yellow green petals were used as plant materials to execute the study. The best performance of adventitious root development was found in 1/4 strength of MS basal salt and the growth was satisfactory in the concentration of 1/2 MS medium. The best condition for adventitious root development and growth was observed in the higher concentration (5%) of sucrose and activated charcoal free 1/4MS medium respectively. Adventitious roots were developed at the controlled culture medium at pH 4.8 with a tendency of suppression with higher levels of pH. However, it was prevailed that the development and growth depended on the concentration of agar. The lower concentration of agar (0.4%) was performed better than that of higher concentration (1.2%), whereas the agar concentration (0.4%) showed the best performance for the development and growth of adventitious roots. For the development of shoots containing node, BA combined with IAA was more effective than kinetin with IAA or NAA. The highest shoot development (3.9 shoots per explant) was performed on MS medium supplemented with 0.1 mg/L BA and 0.5 mg/L IAA.

• Korean Journal of Environmental Agriculture
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• v.13 no.2
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• pp.168-174
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• 1994

The experiments were performed to examine the effects of simulated acid rain (pH 1.0${\sim}$5.0) prepared by mixing sulfuric acid and nitric acid at the ratio of 3 : 1 on germination and growth of seedlings of some floricultural crops. Days to germination showed a one to three days' interval among crops, but pH level did not show any effect on germination for each crop. All seeds used in this experiment did not germinate at pH 1.0. At pH 2.0, the flowering cabbage and geranium still did not germinate, and even though the radicles of seeds were germinated, root hairs did not develop. The length of hypocotyls and radicles appeared to be significantly different according to the pH levels.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.380-383
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• 2000

The effect of on the cell growth, the elaboration of pullulan, the morphology and were the effect of on the molecular weight of pullulan were investigated. A. pullulans showed maximum pullulan production when initial pH 6.5 was 11.98 g/l in shake-flask culture. In batch culture, the maximum pullulan production of 15.16 g/l was obtained at an aeration rate of 0.5 vvm. The mixture of yeast-like form and mycelial form of cells was found at the constant pH 4.5, at which condition, the elaboration of pullulan was high, about 13.31 g/l. However, pullulan with its higher molecular weight (>1,000,000) was produced at the constant pH 6.5.