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排序方式: 共有203条查询结果,搜索用时 31 毫秒
81.
Jeon JH Kim DJ Han JH Yeon SC Bahng SH Myeong BS Chang HH 《Journal of animal science》2005,83(6):1397-1402
Weanling pigs tend to avoid wind, and suckling piglets are thought to be more sensitive to wind than weanlings, owing to their thinner s.c. fat layer. We developed a crush-reducing device based on the anticipated behavior of suckling piglets toward wind and evaluated the performance of the device through field testing. The crush-reducing device consisted of six photo sensors, a controller, six solenoid valves, and an air compressor. In this study, 206 sows and their suckling piglets (Landrace xYorkshire) were investigated to ascertain the individual effects of several factors. Some of the newborn piglets were cross-fostered before the crush-reducing device was implemented. Litter weights were measured on d 0 and 4 to determine the influence of the crush-reducing device on the weights of suckling piglets. The crushing of suckling piglets by sows was affected by season (P < 0.01) and litter size (P < 0.05), but not by the parity of the sows; however, the number of crushed piglets per litter was less (P < 0.01) in the crush-reducing device group (0.05 +/- 0.02 crushed piglets/litter) than in the control group (0.23 +/- 0.04 crushed piglets/litter), regardless of litter size or season. The BW gain of suckling piglets did not differ between the control and the crush-reducing device groups. Based on these results, the crush-reducing device is expected to decrease the number of crushed piglets per litter without influencing the BW gain of suckling piglets, thereby greatly contributing to the productivity of pig breeders. 相似文献
82.
Woo-Jin Jeon Eun-Kyoung Lee Young-Jeong Lee Ok-Mi Jeong Yong-Joo Kim Jun-Hun Kwon Kang-Seuk Choi 《Journal of veterinary science (Suw?n-si, Korea)》2008,9(3):295-300
Despite the intensive vaccination policy that has been put in place to control Newcastle disease virus (NDV), the recent emergence of NDV genotype VII strains in Korea has led to significant economic losses in the poultry industry. We assessed the ability of inactivated, oil-emulsion vaccines derived from La Sota or Ulster 2C NDV strains to protect chickens from challenge with Kr-005/00, which is a recently isolated Korean epizootic genotype VII strain. Six-week-old SPF chickens were vaccinated once and challenged three weeks later via the eye drop/intranasal route. All vaccinated birds were fully protected from disease, regardless of the vaccine strains used. All vaccinated and challenged groups showed significant sero-conversion 14 days after challenge. However, some vaccinated birds, despite being protected from disease, shed the challenge virus from their oro-pharynx and cloaca, albeit at significantly lower titers than the unvaccinated challenged control birds. The virological, serological, and epidemiological significance of our observations with regard to NDV disease eradication is discussed. 相似文献
83.
Generation of neuronal-like cells from umbilical cord blood-derived mesenchymal stem cells of a RFP-transgenic cloned cat 总被引:1,自引:0,他引:1
Jin GZ Yin XJ Yu XF Cho SJ Choi EG Lee YS Jeon JT Yee ST Kong IK 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(7):723-726
Umbilical cord blood (UCB)-derived mesenchymal stem cells (MSCs) are multipotent adult stem cells, which can differentiation into cells of connective tissue and neural lineages. This study investigated the potential for neuronal differentiation of red fluorescent protein (RFP)-transgenic cat UCB-derived MSCs. The cells were cultured in pre-induction medium for 24 hr and in neuronal-induction medium for 72 hr. Immunofluorescent staining showed that 6.85% of the total cells were beta III-tubulin-positive, 3.37% were neurofilament light (NF-L)-positive and 7.04% were neurofilament medium (NF-M)-positive. A beta III-tubulin band was detected by western blot analysis. Our results demonstrate that RFP-transgenic UCB-derived MSCs can be differentiated into neuronal cells in vitro. Thus, RFP-transgenic MSCs could provide alternative tracing material for stem cell transplantation. 相似文献
84.
Association of a single nucleotide polymorphism in the 5' upstream region of the porcine myosin heavy chain 4 gene with meat quality traits in pigs 下载免费PDF全文
Eun‐Seok Cho Kyung‐Tai Lee Jun‐Mo Kim Si‐Woo Lee Hyeon‐Jeong Jeon Seung‐Hwan Lee Ki‐Chang Hong Tae‐Hun Kim 《Animal Science Journal》2016,87(3):330-335
We identified a potential molecular marker associated with meat quality traits in the myosin heavy chain 4, MYH4 gene of Landrace pigs. Sequencing revealed a single nucleotide polymorphism (SNP; g.‐1398G>T) in the 5' upstream region of MYH4. It was significantly associated with the number of type IIa muscle fibers and water‐holding capacity based on filter‐paper fluid uptake. The GG genotype groups had a greater number of type IIa fibers and a larger area composed of type IIa fibers than the other genotype group (P = 0.004 and P = 0.061, respectively). Expression level of MYH4 gene in the genotype TT or GT was higher than in genotype of GG (P < 0.0001). The T allele may enhance expression level of MYH4 gene and then the portion of IIb type fiber in the muscle be increased by the T allelle. Therefore, we suggest that the g.‐1398G>T in the 5' upstream region of the porcine MYH4 may be used as a molecular marker for meat quality traits, although its functional effect is not defined yet. 相似文献
85.
Five different types of polyester geogrids whose nominal tensile strengths vary from 100 to 400 kN/m were investigated. Series
of conventional long-term (ASTM D5262) and stepped isothermal method (SIM, ASTM D6992) tests were performed to evaluate the
long-term creep strain of these geogrids. The conventional long-term creep strains for 10,000 hours varied from 1.32 % and
0.53 %. Knitted geogrids showed higher creep strains than those associated with woven geogrids. The results of SIM tests showed
that a minimum of 6 to 8 steps should be used in order to predict the creep behavior beyond 75-year design life. SIM tests
showed good match with the results obtained from long-term creep tests for woven geogrids. Based upon SIM test results obtained
from the test geogrids, the creep reduction factor of 1.50 is a reasonable value for 75-year design life. 相似文献
86.
Kim SM Jeon JS Kang SW Jung YJ Ly LN Um BH 《Journal of agricultural and food chemistry》2012,60(22):5597-5603
Ligularia fischeri (Ledeb.) Turcz, a commercial leafy vegetable, contains caffeoylquinic acid derivatives (CQAs) as major phenolic constituents. The HPLC chromatograms of leaf extracts collected from different areas in Korea showed a significant variation in CQA amount, and two tri-O-caffeoylquinic acids (triCQAs) were purified and structurally identified by NMR and MS from this plant. Radical scavenging activities among CQAs were found to be increased in proportion to the number of caffeoyl groups. Since this plant prefers damp and shady growth conditions, the effects of sunlight were investigated by growing plantlets in sunlight and shade for four weeks. Greater leaf thickness and higher phenolic contents were found for leaves grown in sunlight than in shade. Four major CQAs-5-mono-O-caffeoylquinic acid (5-monoCQA), and 3,4-, 3,5-, and 4,5-di-O-caffeoylquinic acid (diCQA)-were induced by solar irradiation, whereas the content of these compounds decreased steadily in shade leaves. The leaves of L. fischeri clearly showed adaptation responses to sunlight, and these characteristics can be exploited for cultivation of this plant for potential use as a nutraceutical and functional food. 相似文献
87.
Jae-hong Choi Mi-hyeon Kim Joon-soo Park Jeong-min Jeon Dae-ok Kim A. D. Towns 《Fibers and Polymers》2007,8(1):37-42
In Part 1 of this study, the dyeability, color shade, wash, light fastness and compatibility of homogeneous disperse dyes
on PLA fabric and PET fabric were reported. The present paper (Part 2) focuses on the application of commercial disperse dyes
to PLA fabric. Specific areas of investigation are the coloration properties of dyes originally intended for the production
of high lightfastness polyester fabrics or for application to cellulose diacetate. The compatibility of the eight members
of the dye set was investigated. In terms of lightfastness, the ratings were higher than that of conventional disperse dyes.
In addition, the use of dye combinations to achieve synergistic uptake on PLA was explored leading to the pronounced synergism
with a mixture of CI Disperse Blue 374 and 284. 相似文献
88.
Paddy and Water Environment - Reclaimed soil is known to have high salinity due to poor water permeability. Soil conditioner can improve the permeability of the ground by changing the composition... 相似文献
89.
Ryan L Jeon Caroline Gilbert Jian Cheng Austin M Putz Mike K Dyck Graham S Plastow Frederic Fortin PigGen Canada Jack C M Dekkers John C S Harding 《Journal of animal science》2021,99(8)
Disease resilience refers to the productivity of an animal under disease. Given the high biosecurity of pig nucleus herds, traits that can be measured on healthy pigs and that are genetically correlated with disease resilience, that is, genetic indicator traits, offer a strategy to select for disease resilience. Our objective was to evaluate mitogen stimulation assays (MSAs) on peripheral blood mononuclear cells (PBMCs) from young healthy pigs as genetic indicators for disease resilience. Data were from a natural disease challenge in which batches of 60 or 75 naïve Yorkshire × Landrace piglets were introduced every 3 wk into a continuous flow barn that was seeded with multiple diseases. In this environment, disease resilience traits, including growth, treatment, and mortality rates, were recorded on 3,136 pigs that were genotyped with a high-density marker panel. PBMCs from 882 of these pigs from 19 batches were isolated from whole blood collected prior to the disease challenge and stimulated with five mitogens: concanavalin A (ConA), phytohemagglutinin (PHA), pokeweed mitogen (PWM), lipopolysaccharide (LPS), and phorbol myristate acetate (PMA). The proliferation of cells was evaluated at 48, 72, and 96 h and compared with unstimulated samples (rest count). Heritabilities of cell proliferation were estimated using a model with batch as a fixed effect and covariates of entry age; rest count; complete blood count proportions of lymphocytes, monocytes, eosinophils, and basophils; and pen, litter, and animal genetics as random effects. Heritability estimates were highest for response to ConA (0.30 ± 0.09, 0.28 ± 0.10, 0.17 ± 0.10, and 0.25 ±0.10 at 48, 72, and 96 h after stimulation and for area under the curve across the three time points, respectively). Estimates were in a similar range for response to PHA and PMA but low for PWM and LPS. Responses to ConA, PHA, and PMA were moderately genetically correlated with several disease resilience traits and in the expected direction, but individual estimates were not significantly different from zero due to large SEs. In conclusion, although validation is needed, MSAss, in particular based on ConA, show promise as genetic indicator traits for disease resilience. 相似文献
90.