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81.
Seungmin Ha Seogjin Kang Kwang-Man Park Ji-Yeong Ku Kyoung-Seong Choi Jinho Park 《Journal of veterinary science (Suw?n-si, Korea)》2022,23(6)
BackgroundNeonatal calf diarrhea is a major problem in the cattle industry worldwide. Rotavirus and Cryptosporidium parvum are the primary causative agents, especially during the first three weeks of the calf’s life.ObjectivesThis study investigated the differences in acid-base, electrolytes, and biochemical parameters of diarrheic calves with infection of either rotavirus or C. parvum.MethodsA total of 61 Korean native calves (≤ 20 days old) were divided into two groups based on rotavirus or C. parvum infections: rotavirus infection (n = 44) and C. parvum infection (n = 17). The calves with at a specific blood pH range (pH 6.92–7.25) were chosen for comparison. The acid-base, electrolyte, chemistry, and serum proteins were analyzed, Further, fecal examinations were performed.ResultsCompared to C. parvum-infected calves, the rotavirus-infected calves showed lower levels of total carbon dioxide, bicarbonate (HCO3 −), anion gap, total protein, and albumin/globulin ratio, and significantly lower levels of potassium, globulin, and α2-globulin (p < 0.05). The C. parvum-infected calves (r = 0.749) had stronger correlations between pH and HCO3 − than the rotavirus-infected calves (r = 0.598). Compared to rotavirus-infected calves, strong correlations between globulin and α2-globulin, α2-globulin and haptoglobin were identified in C. parvum-infected calves.ConclusionsThis study is the first to investigate acid-base, electrolyte, and biochemical parameters in calves in response to infections of rotavirus and C. parvum. Although rotavirus and C. parvum cause malabsorptive and secretory diarrhea in similar-aged calves, blood parameters were different. This would help establish the diagnostic and treatment strategies. 相似文献
82.
Min-Jin Kwak Min-Young Park Yong-Soon Choi Junghwan Cho Duleepa Pathiraja Jonggun Kim Hanbae Lee In-Geol Choi Kwang-Youn Whang 《畜牧与生物技术杂志(英文版)》2022,(1):256-264
Background: Gut is a crucial organ for the host’s defense system due to its filtering action of the intestinal membrane from hazardous foreign substances. One strategy to strengthen the gut epithelial barrier function is to upregulate beneficial microflora populations and their metabolites. Sophorolipid(SPL), which is a glycolipid biosurfactant, could increase beneficial microflora and decrease pathogenic bacteria in the gastrointestinal tract.Therefore, herein, we conducted an experiment with b... 相似文献
83.
Hyeok Ran Kwon Gyung Ja Choi Yong Ho Choi Kyoung Soo Jang Nack‐Do Sung Mun Seong Kang Yilseong Moon Seung Kyu Lee Jin‐Cheol Kim 《Pest management science》2010,66(6):634-639
BACKGROUND: Pine wilt disease (PWD) is very complex and has been reported to be caused by pine wood nematode, Bursaphelenchus xylophilus (Steiner & Buhrer) Nickle, and its accompanying bacteria. However, there is no report on the control of PWD by antibacterial agent. The present study was performed to investigate disease control efficacy of antibacterial agents against PWD. RESULTS: Among six antibacterial antibiotics tested, oxolinic acid (OA) showed the strongest antibacterial activity against five bacteria isolated from three strains of pine wood nematode. In in vivo assay, it effectively suppressed the development of PWD in three‐year‐old seedlings of Pinus densiflora Sieb. & Zucc.; it showed 71% control when injected at 3 mg per seedling. A mixture of OA and the nematicidal agent abamectin (Ab) showed higher disease control efficacy against PWD than either OA or Ab alone. In addition, OA alone and a mixture of OA and Ab also controlled PWD in approximately 20‐year‐old pine trees under field conditions. CONCLUSION: This is the first report on the suppression of PWD by OA. The result strongly indicates that PWD could be controlled by antibacterial antibiotic alone and a combination of antibacterial and nematicidal agents. Copyright © 2010 Society of Chemical Industry 相似文献
84.
A certified organic apple (Malus × domestica Borkh.) orchard was established to study the interaction of ground cover management systems (GMS) and nutrient sources (NS) on nitrogen (N) use efficiency and N surplus in the Southern U.S. for three years. Trees treated with green compost (GC) and wood chips (WC), regardless of the NS, had greater N accumulation and leaf N use efficiency compared to the shredded paper or mow-and-blow treated trees. The WC-treated trees had comparably low N surplus relative to the GC trees that induced more [NO3−] in soil or soil solution in the rooting zone in September in year 3. GC trees had the highest [NO3−] mineralization in the soil during winter. GMS had greater overall effects on the tree response variables than did the NS. 相似文献
85.
Ho Seop Yoon Chul Won Park Ho Young Soh Il Woong Park & Sang Duk Choi 《Aquaculture Research》2009,40(2):242-245
The present study was designed to determine the positive effects of artificial illumination on the juvenile black seabream, Acanthopagrus schlegeli , by comparing stomach contents and growth between juveniles exposed to light and those maintained in the absence of light. The major prey items for juvenile black seabream reared in illuminated cages were amphipods (IRI%=50.5), copepods (IRI%=44.7) and polychaetes (IRI%=3.0), whereas those for the juveniles maintained in unilluminated cages were copepods (IRI%=96.0), amphipods (IRI%=3.4) and polychaetes (IRI%=0.6). The specific growth rates (SGR) of the juveniles reared in illuminated cages (0.99%) were significantly higher than those of the juveniles maintained in unilluminated cages (0.78%). 相似文献
86.
Genotypic prevalence of the adhesin involved in diffuse adherence in Escherichia coli isolates in pre-weaned pigs with diarrhoea in Korea 总被引:1,自引:0,他引:1
Ha SK Choi C Jung K Kim J Han DU Ha Y Lee SD Kim SH Chae C 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2004,51(4):166-168
A total of 1002 Escherichia coli strains isolated from pre-weaned pigs with diarrhoea on 1114 swine farms were screened for the presence of the adhesin involved in diffuse adherence (AIDA) gene by polymerase chain reaction (PCR). Escherichia coli isolates that carried AIDA genes were also tested by PCR for the detection of five fimbriae (F4, F5, F6, F18 and F41), heat-stable (STa, STb) and heat-labile (LT) enterotoxin, enteroaggregative E. coli heat-stable enterotoxin 1 (EAST1), and Shiga toxin 2 oedema disease (Stx2e) genes. Twenty-three (2.3%) of the 1002 E. coli isolates carried the gene for AIDA. Among 23 isolates shown to carry genes for AIDA, three carried the AIDA gene as the only shown virulence factor. Other isolates carried other virulence factor genes in addition to AIDA. Four isolates carried genes for at least one of the fimbrial adhesins and enterotoxins. Sixteen isolates carried genes for enterotoxins only. The AIDA may represent an additional virulence determinant in pre-weaned pigs with diarrhoea. 相似文献
87.
Sukyeung Lee Yu-Mi Choi Myung-Chul Lee Do Yoon Hyun Sejong Oh Yeonju Jung 《Genetic Resources and Crop Evolution》2018,65(6):1591-1602
Glutenin largely determines wheat bread baking quality. As high-molecular-weight glutenin subunit (HMW-GS), related to Glu-1 loci, determines wheat flour elasticity, it correlates strongly with bread-making quality. This study was aimed at clarifying genetic variations in bread-making characteristics between East and West Asian wheat landrace germplasms, by investigating HMW-GS allelic composition of 1068 wheat accessions. Herein, the accession number having reported HMW-GS pattern in previous studies was 855. However, the accession number with newly detected HMW-GS patterns was 114. These new HMW-GS patterns were classified into 4 types based on similarity. Eight Korean accessions with these four types were identified. Concerning landrace germplasm nature, 99 accessions showed heterogeneous patterns caused by seed mixture. The Glu-1 loci allelic variation analysis, revealed that the percentages of Glu-A1c (73.6%), Glu-B1b (60.2%), and Glu-D1a (68.5%) were highest at Glu-A1, Glu-B1, and Glu-D1 loci, respectively. The incidence of preferable alleles for bread baking was high in Chinese accessions. In bread-making quality evaluation using Glu-1 score, 24 among 35 accessions with full score were from China. The polymorphic information content index of each origin based on HMW glutenin subunit combination showed that West Asian and neighboring-regional landraces, excluding Afghanistan ones, were more diverse than East Asian landraces excluding Chinese ones. Cluster analysis based on Glu-1 allelic combination showed that many Korean, Japanese, and Afghan accessions were in the same group. However, many Chinese and other West Asian accessions were in the other group despite geographical distance. 相似文献
88.
Recycled polyols from waste polyurethane (PU) foams were grafted onto PU to improve the properties such as tensile strength, shape recovery, low-temperature flexibility, and water compatibility. The recycled polyol was either purified by column chromatography before grafting or was used directly for grafting. The soft segment melting temperature of PU did not notably increase with the addition of polyol, whereas the glass transition temperature increased with increased polyol content. The tensile strength sharply increased at low polyol content and decreased at high polyol content, while the strain at break did not significantly change with an increase in polyol content. The shape recovery at 10 oC notably improved compared with unmodified PU and remained high after four cyclic tests. Polyol-grafted PU demonstrated better lowtemperature flexibility and reduced the water vapor permeability of PU membranes. Overall, grafting recycled polyol onto PU significantly improved the tensile stress, shape recovery, and low-temperature flexibility of PU. 相似文献
89.
Seok-In Yun Hee-Myong Ro Woo-Jung Choi Gwang-Hyun Han 《Journal of Soils and Sediments》2011,11(7):1253-1261
Purpose
Although nitrification plays a key role in the fate of soil nitrogen (N) under global warming, little information is available for the nitrifiers’ response to changing temperatures. Nitrogen isotope fractionation associated with nitrification can be a proxy of nitrifiers’ sensitivity to changing temperature. We hypothesized that the temperature-induced balance between the transport of substrate NH4+ into the microbial cell (supply) and the intracellular NH4+ oxidation (consumption) governs the intracellular NH4+ concentration and then affects nitrification rates and associated isotope fractionations. This study was conducted to understand the microbial response of NH4+ oxidation to changing temperatures by examining the effect of changing temperature on nitrification rate and apparent isotope fractionation. 相似文献90.
The dynamics of attaching antigen to sheep red blood cells using bis-diazotized benzidine (BDB) were studied using purified protein derivative tuberculin as antigen. Factors considered were the concentration of antigen and BDB, temperature, time and simultaneous or consecutive coupling. Simultaneous coupling at 42°C for 10 min gave the most specific haemagglutination reactions and was simple to carry out. 相似文献