• Proceedings of the Korean Society of Fisheries Technology Conference
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• 1998.06a
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• pp.320-321
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• 1998

• Proceedings of the PSK Conference
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• 2000.04a
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• pp.118.1-118.1
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• 2000

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.04a
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• pp.17-17
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• 2022

• Journal of Microbiology and Biotechnology
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• v.18 no.3
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• pp.585-590
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• 2008

Human tropic Porcine Endogenous Retroviruses (PERVs) are the major concern in zoonosis for xenotransplantation because PERVs cannot be eliminated by specific pathogen-free breeding. Recently, a PERV A/C recombinant with PERV-C bearing PERV-A gp70 showed a higher infectivity (approximately 500-fold) to human cells than PERV-A. Additionally, the chance of recombination between PERVs and HERVs is frequently stated as another risk of xenografting. Overcoming zoonotic barriers in xenotransplantation is more complicated by recombination. To achieve successful xenotransplantation, studies on the recombination in PERVs are important. Here, we cloned and sequenced proviral PERV env sequences from pig gDNAs to analyze natural recombination. The envelope is the most important element in retroviruses as a pivotal determinant of host tropisms. As a result, a total of 164 PERV envelope genes were cloned from pigs (four conventional pigs and two miniature pigs). Distribution analysis and recombination analysis of PERVs were performed. Among them, five A/B recombinant clones were identified. Based on our analysis, we determined the minimum natural recombination frequency among PERVs to be 3%. Although a functional recombinant envelope clone was not found, our data evidently show that the recombination event among PERVs may occur naturally in pigs with a rather high possibility.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.8
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• pp.1124-1130
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• 2014

The objective of this study was to determine the responses in the digestibility of dry matter (DM) and amino acid (AA) composition of ileal endogenous flow (IEF) of pigs (initial body weight, $69.1{\pm}6.46$ kg) fed N-free diets (NFD) formulated with different ratios of corn starch to dextrose. Fifteen pigs fitted with a T-cannula at the distal ileum were fed 5 diets according to a triplicated $5{\times}2$ incomplete Latin-square design. Each period consisted of a 5-d adjustment period and 2 d of ileal digesta collection for 12 h on each of d 6 and 7 and between each period, there was a 5-d recovery period to avoid abnormal weight loss. The ratios of corn starch to dextrose investigated were 0:879, 293:586, 586:293, 779:100, and 879:0 for diet numbers 1, 2, 3, 4 and 5, respectively, and chromic oxide (5 g/kg) was used as an indigestible index. Ileal DM digestibility was greater in Diet 1 than that in Diet 4 (89.5% vs 87.3%, p<0.01) but they were not different from Diet 2, 3, or 5. The IEF for most of indispensable AA were not different among diets with the exception of Met, in which a lack of corn starch or dextrose gave lower (p = 0.028) IEF of Met than diets containing corn starch and dextrose. Likewise, the dispensable AA and total AA in the IEF did not differ among diets. The respective IEF of AA (mg/kg of dry matter intake) in pigs fed Diets 1, 2, 3, 4, or 5 were 301, 434, 377, 477,or 365 for Lys, 61, 89, 71, 87, or 61 for Met, and 477, 590, 472, 520, or 436 for Thr. Proline was the most abundant AA in the IEF followed by Gly, Glu, and Asp and together accounted for approximately 50% of the total ileal AA flows of pigs fed NFD. In conclusion, the variation in proportion of corn starch and dextrose in a NFD does not largely affect estimates of IEF of N and AA for growing-finishing pigs.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.10
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• pp.1487-1494
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• 2003

Studies were conducted with intact White Leghorn roosters to determine the true metabolisable energy (TME) and the true amino acid availability (TAAA) in five dehulled and hulled soybean meals produced in China. 60 roosters, kept in individual cages, were fasted for 48 h and then tube-fed 50 g of one of experimental feedstuffs and their excreta was then collected for the subsequent 48 h period. Two separate collection periods were used with each meal being fed to 12 roosters. The birds were given a 15-day recovery period between collection periods. An additional 12 roosters were either fasted or fed a protein-free diet in order to estimate the extent of endogenous losses of energy and amino acids in excreta. The average values per bird for nitrogen loss, endogenous energy losses (EEL) and endogenous energy losses corrected to zero-nitrogen balance ($EEL_n$) were found to be 0.74 g, 47.0 kJ and 21.5 kJ, respectively. It was found that the TME and TAAA values of dehulled soybean meal were higher than those of hulled soybean meal. The TME and nitrogen-corrected TME metabolisable energy values of dehulled soybean meal were 10.58 and 10.74 MJ/kg, respectively, while the corresponding values for hulled soybean meal were 10.03 and 10.27 MJ/kg, respectively. The average indispensable and dispensable amino acid availability of dehulled soybean meal was 92.1 and 93.5%, compared with 89.3 and 91.4% for hulled soybean meal. Dehulled soybean meal would therefore appear to be superior to hulled soybean meal as a source of protein and energy for use in poultry rations.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.3
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• pp.333-339
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• 2010

The objectives of this study were to use the NRC-2001 model and DVE/OEB system to model potential nutrient supply to ruminants and to compare frost damaged (also called "frozen" wheat with normal wheat. Quantitative predictions were made in terms of: i) Truly absorbed rumen synthesized microbial protein in the small intestine; ii) Truly absorbed rumen undegraded feed protein in the small intestine; iii) Endogenous protein in the digestive tract; iv). Total truly absorbed protein in the small intestine; and v). Protein degraded balance. The overall yield losses of the frozen wheat were 24%. Results showed that using the DVE/OEB system to predict the potential nutrient supply, the frozen wheat had similar truly absorbed rumen synthesized microbial protein (65 vs. 66 g/kg DM; p>0.05), tended to have lower truly absorbed rumen undegraded feed protein (39 vs. 53 g/kg DM; p<0.10) and had higher endogenous protein (14 vs. 9 g/kg DM; p<0.05). Total truly absorbed protein in the small intestine was significantly lower (89 vs. 110 g/kg DM, p<0.05) in the frozen wheat. The protein degraded balance was similar and both were negative (-2 vs. -1 g/kg DM). Using the NRC-2001 model to predict the potential nutrient supply, the frozen wheat also had similar truly absorbed rumen synthesized microbial protein (average 56 g/kg DM; p>0.05), tended to have lower truly absorbed rumen undegraded feed protein (35 vs. 48, g/kg DM; p<0.10) and had similar endogenous protein (average 4 g/kg DM; p>0.05). Total truly absorbed protein in the small intestine was significantly lower (95 vs. 108 g/kg DM, p<0.05) in the frozen wheat. The protein degraded balance was not significantly different and both were negative (-16 vs. -19 g/kg DM). In conclusion, both models predict lower protein value and negative protein degraded balance in the frozen wheat. The frost damage to the wheat reduced nutrient content and availability and thus reduced nutrient supply to ruminants by around 12 to 19%.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.10
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• pp.1357-1363
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• 2012

Pigs may need to be exploited as xenotransplantation donors due to the shortage of human organs, tissues and cells. Porcine endogenous retroviruses (PERVs) are a significant obstacle to xenotransplantation because they can infect human cells in vitro and have the potential for transmission of unexpected pathogens to humans. In this research, 101 pigs, including four commercial breeds (23 Berkshire, 13 Duroc, 22 Landrace and 14 Yorkshire pigs), one native breed (19 Korean native pigs) and one miniature breed (10 NIH miniature pigs) were used to investigate insertional variations for 11 PERV loci (three PERV-A, six PERV-B and two PERV-C). Over 60% of the pigs harbored one PERV-A (907F8) integration and five PERV-B (B3-3G, B3-7G, 742H1, 1155D9 and 465D1) integrations. However, two PERV-A loci (A1-6C and 1347C1) and one PERV-B locus (B3-7F) were absent in Duroc pigs. Moreover, two PERV-C loci (C2-6C and C4-2G) only existed in Korean native pigs and NIH miniature pigs. The results suggest that PERV insertional variations differ among pig breeds as well as among individuals within a breed. Also, the results presented here can be used for the selection of animals that do not have specific PERV integration for xenotransplantation research.

• Journal of the Korean Institute of Landscape Architecture
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• v.20 no.1
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• pp.29-38
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• 1992

The primary objective of this study is to investigate factors and variables which have significant effects on user satisfaction with recreational facilities in Children's Grand Park in Pusan City, theregby to establish the developmental way of urban park and open space. To test the causal models of this research, the data were gathered by self-administered questionnaires from 1085 households in Pusan City which were selected by the multi-stage probability sampling method. The analysis of the data primarily consists of two phase : The fist analysis dealt exploratory factor analysis which identified major factors involved in satisfaction with recreational facilities in Children's Grand Park and the second analysis tested the fit of the causal models of this research by employing LISREL methodology. The factor analysis identified that five factors are involved in satisfaction with recreational facilities. The five factors of satisfaction with recreational facilities are convenience and maintanance facilities, learnded recreational facilities, spaces for repose and relaxation, spaces for active recreation failities, and facilities for health and physical facilities. The second phase analysis tested the fit of the causal models for satisfaction with recreational facilities to the data and identified statistically significant causal linkage among overall satisfaction with Children's Grand Park, other endogenous factors and exogenous variables. Overall fits of both causal models were very good. Among endogenous factors, facilities for repose and relaxation, facilities for convenience and maintenance, learnded recreational facilities were identified as having significant effects on overall satisfaction. Exogenous variables which have significant effects on endogenous variables were also identified. These significant relationships indicate important factors and variables that should be considered in planning and development of urban park and open space. On the basis of these significant causal relationships, way for delovepment of urban park and open space were suggested.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.6
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• pp.809-816
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• 1997

The present study was designed to investigate whether endogenous nitric oxide(EDNO) is involved in submandibular vasodilation and salivation induced by parasympathetic nerve stimulation. Effects of $N^w$-nitro-L-arginine-methyl ester (L-NAME) which blocks the synthesis of EDNO from L-arginine on the submandibular vasodilation and salivation induced by chords stimulation or administration of various vasodilators were examined in anesthetized cats. Effect of L-NAME on $K^+$ efflux induced by carbachol was also examined using the excised submandibular slice in vitro. In the submandibular slices, acetylcholine$(10^{-5}\;mol/L)$ or vasoactive intestinal polypeptide$(VIP,\;10^{-5}\;mol/L)$ increased $NO_2$ contents, which was Prevented by pretreatment with L-NAME. Salivary secretion in response to the chords stimulation$(3\;V,\;1\;msec,\;10{\sim}20\;Hz)$ was completely blocked by treatment with atropine(1 mg/kg). Increased blood flow response to the low frequency(1, 2, 5 Hz) stimulation was significantly reduced, whereas the blood flow induced by the higher frequency(10,20 Hz) stimulation was not affected. Lingual-arterial infusion of L-NAME(100 mg/kg) significantly diminished the vasodilatory and salivary responses to the chorda stimulation at all stimuli frequencies used. Intra-arterial infusion of L-NAME(100 mg/kg markedly diminished the vasodilatory responses to acetylcholine$(5\;{\mu}g/kg)$, VIP$(5\;{\mu}g/kg)$ or bradykinin$(5\;{\mu}g/kg)$. In the excised submandibular slice, $K^+$ efflux in response to carbachol$(10^{-5}\;mol/L)$ was significantly decrease by pretreatment with L-NAME$(10^{-5}\;mol/L)$. In the isolated submandibular artery precontracted with phenylephrine$(10^{-5}\;mol/L)$, the vasorelaxation induced by ACh$(10^{-7}\;mol/L)$ was reversed into a contraction by methylene blue$(10^{-4}\;mol/L)$. These results suggest that EDNO may play an important role in vasodilation and secretion of the submandibular gland.