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1.
Eric Lim Teik Chung Michael Predith Frisco Nobilly Anjas Asmara Samsudin Faez Firdaus Abdullah Jesse Teck Chwen Loh 《Tropical animal health and production》2018,50(8):1727-1732
Brachiaria decumbens is an extremely productive tropical grass due to its aggressive growth habit and its adaptation to a varied range of soil types and environments. As a result of the vast availability, treated B. decumbens demonstrates as a promising local material that could be utilised as an improved diet for sheep and goats. Despite the fact that the grass significantly increases weight gains in grazing farm animals, there were many reports of general ill-thrift and sporadic outbreaks of photosensitivity in livestock due to the toxic compound of steroidal saponin found in B. decumbens. Ensiling and haymaking were found to be effective in removing toxin and undesirable compounds in the grass. Biological treatments using urea, activated charcoal, polyethylene glycol, and effective microorganisms were found to be useful in anti-nutritional factor deactivation and improving the nutritive values of feedstuffs. Besides, oral administration of phenobarbitone showed some degree of protection in sheep that fed on B. decumbens pasture. In this review, we aim to determine the effect of B. decumbens toxicity and possible treatment methods on the grass to be used as an improved diet for small ruminant. 相似文献
2.
Kyung-Ho Ma Jae-Gyun Kwag Weiguo Zhao Anupam Dixit Gi-An Lee Haeng-Hoon Kim Ill-Min Chung Nam-Soo Kim Jae-Sun Lee Jae-Jun Ji Tae-San Kim Yong-Jin Park 《Scientia Horticulturae》2009,122(3):355-361
Here we characterized eight novel polymorphic SSR markers, developed from an enriched genomic library of garlic (Allium sativum L.). These SSRs produced a total of 64 alleles across 90 garlic accessions, with an average of 8 alleles per locus. Values for observed (HO) and expected (HE) heterozygosity ranged from 0.16 to 0.77 (mean = 0.44) and from 0.22 to 0.86 (mean = 0.65), respectively. Six loci deviated significantly (P < 0.05) from Hardy–Weinberg equilibrium (HWE). The averages of gene diversity and PIC values were 0.65 and 0.62, respectively. The mean genetic similarity coefficient was 0.4380, indicating that among garlic accessions existed wide genetic variation. Based on 64 alleles obtained by 8 SSRs, a phenogram was constructed to understand the relationships among the 90 accessions. These newly developed SSRs should prove very useful tools for genotypes identification, assessment of genetic diversity and population structure in garlic. 相似文献
3.
Flavonoid constituents of Chorizanthe diffusa with potential cancer chemopreventive activity 总被引:11,自引:0,他引:11
Chung HS Chang LC Lee SK Shamon LA van Breemen RB Mehta RG Farnsworth NR Pezzuto JM Kinghorn AD 《Journal of agricultural and food chemistry》1999,47(1):36-41
An ethyl acetate-soluble extract of Chorizanthe diffusa was found to exhibit significant antioxidant activity, as judged by scavenging stable 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radicals and inhibition of 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced free radical formation with cultured HL-60 cells. Bioassay-directed fractionation of this extract using the DPPH antioxidant assay as a monitor led to the isolation of five structurally related flavonoids (1-5), including the novel compound 5,8,3',4',5'-pentahydroxy-3, 7-dimethoxyflavone (1). Isolates 1-5 demonstrated varying degrees of antioxidant or antimutagenic activity. Two of the compounds, 5,7,3', 4'-tetrahydroxy-3-methoxyflavone (2) and quercetin (4), were subsequently found to inhibit carcinogen-induced preneoplastic lesions in a mouse mammary organ culture model. Inhibitory activity of this type is known to correlate with cancer chemopreventive effects in full-term models of tumorigenesis. 相似文献
4.
Loss of pendimethalin in runoff and leaching from turfgrass land under simulated rainfall 总被引:2,自引:0,他引:2
A field study was undertaken to investigate runoff and leaching loss of the herbicide pendimethalin in turfgrass land of loamy sand soil. A series of plots constructed in a golf course fairway were surface-applied with pendimethalin SC formulation at the rate of 2. 25 or 4.50 kg a.i./ha and subjected to simulated rainfall at 2.0 cm/day for 10 consecutive days. Runoff losses of pendimethalin were the highest at the first rainfall and then gradually decreased with time. The first runoff event contained pendimethalin in its highest concentration, and in subsequent runoff samples the concentration decreased exponentially. The ranges of pendimethalin concentration were 80.9-18.2 and 177.4-48.6 microgram/L in the standard and double doses, respectively. Total losses by 20 cm of rainfall for 10 days reached 0.81 and 1.22% of the initial deposits at 2.25 and 4.50 kg a. i./ha, respectively. Pendimethalin concentration in the leachate collected at 30-cm soil depth was quite lower than that in the runoff, and the concentration rapidly decreased from 4.3-4.7 to 0. 2-0.4 microgram/L during the 10 days of rainfall treatment. Soil residue analysis at 45 and 90 days after pendimethalin treatment showed that more than 90% of the residue remained at the top 10 cm of soil depth. Low runoff and leaching confirmed that lateral and downward movement of the herbicide should be limited in turf soil. The half-life of pendimethalin under field conditions was 23-30 days and was not affected by application dose and rainfall treatment, but longer persistence was observed under laboratory conditions. Considering low runoff and leaching, as well as relatively short persistence in soil, it is concluded that little environmental carryover of pendimethalin would be expected in turfgrass land. 相似文献
5.
Chung Yong Suk Silva Renato Rodrigues Park Minwoo Lee Sanghyeob 《Journal of Crop Science and Biotechnology》2019,22(1):17-20
Journal of Crop Science and Biotechnology - The ionizing radiation methods, including X-rays, gamma rays, and neutrons to create variation is well established and used in major crops. Many... 相似文献
6.
Experimental model of swine pneumonic pasteurellosis using crude Actinobacillus pleuropneumoniae cytotoxin and Pasteurella multocida given endobronchially. 下载免费PDF全文
This study was designed to develop and characterize a swine pneumonic pasteurellosis model by concurrent introduction of Pasteurella multocida type A and Actinobacillus pleuropneumoniae crude cytotoxin. After a series of preliminary experiments, a combination of 4 x 10(9) P. multocida and 4,000 toxic units of A. pleuropneumoniae crude cytotoxin was determined to produce optimal results. A total of 48 pigs were divided into four groups of 12 pigs each. The control group received buffered saline only. Four pigs from each group were randomly selected for necropsy 3, 7 and 14 days postinoculation (PI). Inoculation of pigs with P. multocida and A. pleuropneumoniae cytotoxin (group 1) resulted in moderate to severe pneumonia. Pasteurella multocida was isolated from pneumonic lesions, grossly normal lung, and bronchial lymph nodes of all group 1 pigs throughout the 14 day experimental period. Pathological changes typical of field cases of swine pneumonic pasteurellosis were produced. Pigs inoculated with P. multocida alone (group 2) had pneumonic lesions and P. multocida was reisolated from lungs at three days PI. Pasteurella multocida was not isolated from these pigs at 7 and 14 days PI, except for one pig in which an abscess developed in the thorax. Pulmonary lesions induced by A. pleuropneumoniae crude cytotoxin alone (group 3) were transient and resolved by seven days PI. Group 1 pigs had significantly greater lung lesion volumes than group 2 and 3 pigs at 3, 7 and 14 days PI. Statistical analysis indicated a significant interactive effect of P. multocida and A. pleuropneumoniae cytotoxin on the development of lung lesion volumes at 7 and 14 days PI (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
7.
Hyun-Jung Suh Dai Jung Chung A-Jin Lee Hyo-Jin Chung Dae-Hyun Kim Ki-Dong Eom Sun Hee Do Hwi-Yool Kim 《The Canadian veterinary journal. La revue veterinaire canadienne》2015,56(10):1025-1028
A 10-year-old Maltese dog was presented with a firm mass on the left side of his neck. Physical examination confirmed a firm mass in the left and a submandibular swelling in the right cervical region. Sialolithiasis and associated sialocele in both mandibular salivary glands were suspected and bilateral sialoadenectomy was performed. The stones were identified as non-mineral sialoliths. 相似文献
8.
Comparison of the canine corneal epithelial cell sheets cultivated from limbal stem cells on canine amniotic membrane,atelocollagen gel,and temperature‐responsive culture dish 下载免费PDF全文
9.
High‐Level Ciprofloxacin‐Resistant Campylobacter jejuni Isolates Circulating in Humans and Animals in Incheon,Republic of Korea 下载免费PDF全文
J. S. Kim M. Y. Lee S. J. Kim S.‐E. Jeon I. Cha S. Hong G. T. Chung M.‐J. Huh Y.‐H. Kang C.‐K. Yoo J. Kim 《Zoonoses and public health》2016,63(7):545-554
Campylobacter jejuni is one of the major causative pathogens of outbreaks or sporadic cases of diarrhoeal diseases worldwide. In this study, we compared the phenotypic and genetic characteristics of C. jejuni isolates of human and food‐producing animal origins in Korea and examined the genetic relatedness between these two groups of isolates. Regardless of isolation source, all C. jejuni isolates harboured four virulence genes, cadF, cdtB, ciaB and racR, whereas the wlaN and virB11 genes were more frequently observed in human isolates. Antimicrobial susceptibility testing showed that the majority of C. jejuni isolates displayed high‐level resistance to fluoroquinolone (95.2%) or tetracycline (76.2%) antibiotics, and 12.4% of isolates exhibited multidrug resistance (more than three classes of antibiotics tested). Pulsed‐field gel electrophoresis (PFGE) of all Campylobacter isolates revealed 51 different SmaI‐PFGE patterns and six major clusters containing both human and animal isolates. These results indicate that genetically diverse strains of C. jejuni with antimicrobial drug‐resistance and virulence properties have prevailed in Incheon. Nevertheless, some particular populations continue to circulate within the community, providing the evidence for an epidemiological link of C. jejuni infections between humans and food‐producing animals. Therefore, the continued monitoring and surveillance of C. jejuni isolates of human and food‐producing animal origins are required for public health and food safety. 相似文献
10.
广州地区十字花科蔬菜花叶病(主要病毒是芜菁花叶病毒的油菜毒系和芜菁毒系)的越夏寄主,根据11年来的观察特别是1956—1958年间的实地调查结果,主要是小白菜、菜心和西洋菜。在野生植物中曾发现过2株蔊菜和1株荠菜自然感病,说明野生植物不是本病的重要毒源。室内试验结果证明,此病的自然传染媒介为萝卜蚜、桃蚜和普通红蜘蛛。黄条跳(虫甲)、斜纹夜盗蛾和菜粉蝶都不是本病的虫媒,病株的种子不会传病,中国菟丝子也不会传递本病。在带有未腐熟的病菜残体的土里进行直播,长出来的菜苗没有发病的;但是把菜苗移植在这样的土里,会有极小量的植株感病。根据1956年7月至1958年6月,每十日田间调查一次结果:萝卜蚜是广州地区最重要的传病媒介,桃蚜每年只在3—4月间略有发生,作用不大。根据这24个月的田间发病率,萝卜蚜(有翅蚜及无翅蚜)的虫口密度和气候情况,我们认为本地区本病的发生及流行程度主要受降水量和降水天数所影响,并认为可以从降水情况来预测约30日后的病害流行程度。 相似文献