• Journal of Microbiology and Biotechnology
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• v.26 no.5
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• pp.876-882
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• 2016

Tylosin has been used as a livestock feed additive and antibiotic growth promoter for many years. However, the mode of action by which tylosin enhances animal growth is unclear. We used high-throughput sequencing of 16S rRNA genes to investigate the effects of tylosin as a feed additive on swine gut microbiota. No significant difference in the rate of weight increase was observed between control and tylosin-treated pigs during a 10-week feeding trial. However, tylosin-treated pigs showed rapid increases in the relative abundance of the phylum Firmicutes. Increases in Firmicutes species are associated with (so-called) obese-type gut microbiota. The abundance of species of four families of the phylum Firmicutes (Streptococcaceae, Peptococcaceae, Peptostreptococcaceae, and Clostridiaceae) correlated positively with host weight gain. The abundance of Streptococcaceae family bacteria was least affected by tylosin treatment. Distribution analysis of operational taxonomic units (OTUs) showed that both control and tylosin-treated pigs exhibited similar OTU alterations during growth. However, the tylosin-treated group showed distinctive alterations in gut microbiota when the host weighed approximately 60 kg, whereas similar alterations occurred at around 80 kg in the control group. Our results suggest that use of tylosin accelerates maturation of swine gut microbiota rather than altering its composition.

• Journal of Fisheries and Marine Sciences Education
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• v.25 no.6
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• pp.1285-1293
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• 2013

This study was conducted to investigate the effects of dietary inclusion of various additives Solid sulfur, fucoidan, and glucan on growth performance and immune responses in Juvenile olive flounder paralichthys olivaceus. Six experimental diets supplemented with : no additives (CON); 0.5 and 1.0% solid sulfur (S); 0.2 and 0.4% fucoidan (F); 0.1% glucan (G) of these additives diet on a dry-matter basis. Fish averaging $8.2{\pm}0.17g$ were fed one of six experimental diets in triplicate groups for 6 weeks. By the end of the feeding trial, weight gain, feed efficiency, specific growth rate, protein efficiency ratio, hepatosomatic index and condition factor of fish fed diet CON were significantly lower then those of fish fed the all additives diets (P < 0.05). In challenge test, fish were infected by intraperitonel injection of 0.1 ml bacterial suspension with Edwardsiella tarda per fish after the feeding trial. As a result fish fed All additive diet showed a lower cumulative mortality then did fish fed CON diet throughout the challenge test. In conclusion, these results indicated that solid sulfur, fucoidan and glucan enhanced the growth, feed efficiency and non-specific immune activity of juvenile flounder and protect the fish against microbial infections.

• KSBB Journal
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• v.17 no.6
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• pp.555-559
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• 2002

Three different strains of Aureobasidium pullulans were grown in batch cultures to compare their abilities of enzyme production. It was found that specific enzyme activity was the highest with strain ATCC 9348 and the enzyme production was closely coupled to growth. Studies on morphology during the growth of A. pullulans revealed that mycelia cells were dominant at the initial stages of growth. However, yeast-like cells and chlamydospores were dominant in the latter stages of batch culture. The pattern of morphological changes during the growth period was not affected by pH. However, it appears that the ratio of intra- to extracellular enzyme activity tended to increase with fermentation time irrespective of the pH employed, suggesting that the secretion efficiency of intracellular enzyme to broth likely depends on cell morphology Using molasses as a cheap source of sucrose, enzymatic production of fructo-oligosaccharides as a feed additive with A. pullulans cells could be achieved successfully at 55$\^{C}$ and pH 5.5.

• Applied Biological Chemistry
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• v.40 no.5
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• pp.409-415
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• 1997

In order to find out the relationship between contained water and coloring rate of thiamine monosalts in preparations, three kinds of thiamine monorhodanate, -monoiodide, -monobromide were manufactured and investigated as powders, granules and compressed tablets, respectively. Apparent coloring rate constants and solubility in accordance with temperature changes were measured. Nature of contained water and coloration of thiamine monosalts in preparations was examined in detail. It was thereby found that if water attached in a free state, coloration occured whose degree was approximately proportional to the quantity of such water, and a linear relation was found to hold between the logarithm of the apparent coloring rate constants and the reciprocal of the absolute temperature in granules and compressed tablets.

• Food Science of Animal Resources
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• v.28 no.4
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• pp.512-516
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• 2008

To search for anit-H5N1 influenza virus agent, the anti-viral activity of methanol and aqueous extracts from thirty medicinal plants were examined in this study. The plant material (30 g) was extracted with methanol (300 mL) for 24 hr at room temperature. Methanol extracts were filtered and evaporated, then freeze-dried. Aqueous extracts were prepared with dried plant material (30 g) and hot distilled water (300 mL). After 3 hr, the aqueous extracts were filtered and evaporated, then lyophilized. Extracts prepared from different plants were tested the antiviral activity against influenza viruses [A/vietnam/1194/04 (H5N1)-NIBRG-14] using the hemagglutination (HA) assay. Among the test plants, Asarum sieboldii was found to be a potent inhibitor of H5N1 influenza virus in MDCK cell culture. Virus titers were 7 log, whereas with methanol extract of Asarum sieboldii for 48 hr titers were 3 log, indicating that methanol extract of Asarum sieboldii inhibited the H5N1 influenza viruses from the infected cells.

• Journal of the Korean Society of Industry Convergence
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• v.25 no.4_2
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• pp.699-706
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• 2022

In this study, Directed energy deposition (DED) among additive manufacturing is applied to repair damaged spindle key parts of planner miller. The material of the spindle key is SCM415, and the P21 Powder is used. In order to find the optimal deposition conditions for DED equipment, a single-line deposition experiment is conducted to analysis five parameters. The laser power affects the width, and the height is a parameter affected by coaxial gas and powder gas. In addition, laser power, powder feed rate, coaxial gas, and powder gas are parameters that affect dilution. Otimal deposition is that 400 W of laser power, 4.0 g/min of powder feed rate, 6.5 L/min of coaxial gas, 3.0 L/min of powder gas and 4.5 L/min of shield gas. By setting the optimum conditions, a uniform deposition cross section in the form of an ellipse can be obtained. Damage recovery process of spindle key consists of 3D shape design of the base and deposition parts, deposition path creation and deposition process, and post-processing. The hardness of deposited area with P21 powder on the SCM415 spindle key is 336 HV for the surface of the deposition, 260 HV for the boundary area, and 165 HV for the base material.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.5
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• pp.634-643
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• 2023

The effects of dietary supplementation with fermented blood meal (FBM) in two forms were evaluated on the growth performance, hematological parameters, innate immune response, antioxidant capacity, digestive enzyme activity and intestinal histology of Japanese eel Anguilla japonica. A commercial powder feed was used as a basal diet (Con). Six other diets were prepared by supplementing 2, 4 and 6% FBM either in powder or liquid form to the Con diet (designated as P2, P4, P6, L2, L4 and L6, respectively). In total 420 eels (initial mean body weight: 55.1±1.71 g) were distributed into 21 tanks (450L) at a density of 20 eels per tank. Three replicate groups of fish were fed one of the seven diets twice daily for 12 weeks. No significant differences were observed in the growth performance and survival among all groups. Fish fed FBM-containing diets showed significantly improved hematological parameters, innate immunity and antioxidant capacity than those in the Con group. Fish fed FBM-containing diets showed significantly enhanced digestive enzyme activity, villus length and goblet cells than those in fish fed Con diet. These results indicate that both powder and liquid FBM could be a good functional feed additive to improve innate immunity and digestion in Japanese eel.

• Korean Journal of Poultry Science
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• v.32 no.1
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• pp.67-72
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• 2005

Forty-wk-old 480 ISA Brown layers were used in a 10-wk feeding trial to investigate the effects of additional various levels of limestone to a low calcium diet without any calcium additives on the performance of laying hens. There were significant differences in average egg weight (P<0.05) without any specific trend among treatments and hen-day egg production was not influenced by the dietary treatments. Daily intake and conversion per kg egg of feed excluded the calcium supplement were significantly reduced (p<0.05) as the level of additional calcium supplement increased in both types of layer diet, while those of feed included the calcium source were significantly increased (P<0.05) as the level of additional calcium supplement increased. Egg specific gravity, eggshell breaking strength and thickness were increased as the level of additional calcium supplement increased, however the significant differences were found only in egg specific gravity It would be possible to reduce the daily feed intake and feed conversion and to improve the eggshell quality by feed the low calcium diet devoid of calcium supplement from the conventional laying hen diet and by supply the additional calcium source at 3 to 4 p.m. instead of the continuous feeding of conventional high calcium diet.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.4
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• pp.497-503
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• 2004

The effect of adding carbohydrate-rich feedstuffs to sweet potato leaves (SPL) on silage quality was studied using a total of 180 laboratory silos. Silage quality was assessed by changes of pH, dry matter (DM), crude protein (CP) and ammonia nitrogen ($NH_{3}$-N). Pre-wilted SPL was mixed with cassava root meal (CRM), sweet potato root meal (SPM) or sugar cane molasses (Mo) at levels of 0, 30, 60 and 90 g $kg^{-1}$ (air-dry weight of additives to pre-wilted weight of SPL). Samples for assessing silage quality were collected after mixing the SPL with the additive and thereafter at 7, 14, 28 and 56 days of ensiling. There was a marked decrease in pH after 7 days and the pH remained low and stable until day 56. Addition of 60 and 90 g $kg^{-1}$ resulted in a lower pH (p<0.05) than the other treatments. The DM content of the silage increased (p<0.05) with increasing levels of additive, while there were no differences in DM with time of ensiling. The CP content of the silage decreased (p<0.05) with increasing levels of additive. The CP content did not change up to 28 days, but was lower (p<0.05) after 56 days in all treatments. The $NH_{3}$-N levels were increasing (p<0.05) with time of ensiling, and were lower (p<0.05) with additive levels of 60 g $kg^{-1}$ or higher. Also, the additive source affected the $NH_{3}$-N values, with the lowest values found for Mo. Castrated male pigs (Large White$\times$Mongcai) were used in 4$\times$4 Latin square design to study the total tract digestibility and nitrogen (N) utilisation of diets with inclusion of ensiled SPL. The diets were based on cassava root meal with inclusion of protein from either fish meal (C) or SPL ensiled with CRM (D1), SPL ensiled with SPM (D2) and SPL ensiled with Mo (D3). The digestibility of DM, organic matter (OM) and CP were higher (p<0.05), and the digestibility of crude fibre (CF) was lower (p<0.05), in diet C than in diets D1, D2 and D3. However, there were no differences (p>0.05) in digestibility of dietary components between diets D1, D2 and D3. Also, the excretion of N in faeces was higher (p<0.05) and the N retention was lower (p<0.05) in diets D1, D2 and D3 than in diet C. It can be concluded from the present experiments, that a good quality silage can be produced from pre-wilted SPL by addition of 60 g $kg^{-1}$ of either CRM, SPM or Mo. Diets with inclusion of 450 g ensiled SPL $kg^{-1}$ DM showed a high digestibility of dietary components and thus ensiled SPL should be considered as a potential feed resource for growing pigs.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.8
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• pp.1209-1223
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• 2009

In this review, the terminology that is used to describe ileal amino acid (AA) digestibilities in piglet feed ingredients is defined. If one accepts that the determination of AA digestibilities should be based on the ileal analysis method, one should consider that ileal digesta contains variable amounts of endogenous crude protein (CP), which originates mainly from digestive secretions, sloughedoff epithelial cells and mucins. The ileal endogenous CP and AA losses are separated into basal ileal endogenous CP and AA losses ($IAAL_{B}$), which are not influenced by the feed ingredient composition, and specific ileal endogenous CP and AA losses ($IAAL_{S}$), which are induced by feed ingredient characteristics such as level and type of fiber and anti-nutritional factors (ANF). Depending how ileal endogenous CP and AA losses are considered in the measurement of CP and AA digestibilities, digestibility values are expressed as apparent (AID), standardized (SID), or true (TID) ileal digestibilities of CP and AA. The main concern associated with the use of AID values in diet formulation for pigs is that they are not additive in mixtures of feed ingredients. Consequently, the concept of standardized ileal CP and AA digestibilities was introduced by correcting AID values for basal ileal endogenous CP and AA losses ($IAAL_{B}$). The correction for both $IAAL_{B}$ and $IAAL_{S}$ yields TID values, however, routine procedures to measure $IAAL_{S}$ are not yet available. In principle, SID values should be preferred, because they represent the fundamental properties of the feed ingredient. There exist only few reports on SID of CP and AA in feedstuffs frequently used in piglet nutrition. These include soybeans (SB), soybean meal (SBM), soy proteins (SP), soy protein concentrate (SPC), soy protein isolate (SPI), corn gluten (CG), wheat gluten (WG), pea protein (PeaP), potato protein (PotP), fish meal (FM) and whey proteins (WP), but the results obtained are inconsistent. Differences in SID values within feed ingredients may, at least in part, be attributed to different processing conditions or inherent differences of the assay feed ingredients. Moreover, there is some evidence that the determination of SID values and $IAAL_{B}$ in piglets may be confounded by the dietary CP level of the assay diet, age and (or) body weight (BW), the level of feed intake or the methodological approach used to determine $IAAL_{B}$.