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771.
Ctenocephalides felis were killed and collected from 92 cats in Alabama, Maryland, and Texas. The fleas and blood from the corresponding cat were digested and assessed in polymerase chain reaction assays that amplify DNA of Ehrlichia species, Anaplasma phagocytophilum, Neorickettsia risticii, Mycoplasma haemofelis, 'Candidatus M haemominutum' and Bartonella species. DNA consistent with B henselae, B clarridgeiae, M haemofelis, or 'Candidatus M haemominutum' was commonly amplified from cats (60.9%) and their fleas (65.2%). Results of this study support the recommendation to maintain flea control on cats in endemic areas.  相似文献   
772.
Feline pyoderma is a disease entity more prevalent than previously described. Diagnosis is made by finding bacteria in the presence of inflammatory cells or bacterial phagocytosis on routine cytological examination. Diseases leading to secondary bacterial pyoderma include allergic and inflammatory skin diseases, parasitosis, feline chin acne, and others. Lesions of feline pyoderma are variable and include crusted and eroded papules, pustules, furuncles, eroded to ulcerated plaques with variable exudation and crusting, and linear to nodular ulcerative granulomatous lesions. Three cases of feline pyoderma responsive to antimicrobial therapy are discussed: case 1, a 10.5-year-old male neutered domestic short hair with eosinophilic lip ulcer, case 2, a 7-year-old male neutered domestic short hair with multiple cutaneous eosinophilic plaques, and case 3, an 8-month-old male neutered domestic short hair cat with Pseudomonas dermatitis, vasculitis, and panniculitis. Antibiotic selection for treatment of feline pyoderma should be based on cytological examination, and culture and sensitivity in unresponsive cases.  相似文献   
773.
Information and communication technologies (ICTs) have been shown to be useful in agricultural knowledge systems to improve communication linkages among research, extension services, and farmers. The end result would be new information and technologies being made available to those who need it the most in larger numbers and in a timelier manner. While the role of ICTs in stimulating technological, organizational, institutional, and policy innovations in developing countries has been recognized, in many Caribbean States where ICTs are becoming readily available, the development and use of ICT in agricultural research and innovation systems remain underexploited, despite the fact that the agricultural sector in these developing nations accounts for a significant amount of the total employed labor force. This article traces key developments in ICT use in the agricultural sector in the Caribbean region, while highlighting the challenges as well as the potential of this technology. Several initiatives in the region are described and suggestions made for the development of innovative, appropriate, and efficient information and communication systems.  相似文献   
774.
Global papaya production is severely affected by papaya ringspot disease caused by Papaya ringspot virus (PRSV). Management of this potyvirus is challenging, due to 1) its non-persistent transmission by numerous aphid species and 2) the diversity of PRSV strains that exists within a country or between different geographical regions. Papaya cultivars with transgenic resistance have reduced the impact of the disease. There are no effective alternatives to transgenic resistance available in areas where disease pressure is high. In Hawaii, transgenic papayas such as “SunUp” and “Rainbow” have remained resistant to PRSV more than two decades saving the commercial papaya industry. Following the success in Hawaii, researchers from other countries have focused on developing PRSV-resistant transgenic papaya. These transgenic cultivars often demonstrated an initial transitory resistance that was ultimately overcome by the virus. For other cases, resistance was inconsistent. That is, some transgenic lines were resistant while others were not. Transgenic cultivars are now losing PRSV-resistance for various reasons in China and Taiwan. In this review, we present an update on work with transgenic papaya with resistance to PRSV. The focus is on factors affecting transgenic resistance in papaya and our attempt to explain why the Hawaiian scenario of complete and durable resistance has not been replicated in other regions. The utilization of more recent technologies to the development of virus resistance in papaya is also discussed.  相似文献   
775.
Nutritional information on food labels helps consumers make informed decisions about what they chose to consume. This study, conducted among 320 consumers in Trinidad, West Indies, examined consumers' use of various informational components of the label and the influence of health-related factors on use of such information. The study found that, although there was a fairly high reading of food label information, fats and sodium information were not given the required attention. Six variables—(a) diabetes; (b) allergies; (c) gender; (d) level of schooling; (e) fast food consumption; and (f) fiber consumption—significantly impacted the use of food label information.  相似文献   
776.
Gambierdiscus and Fukuyoa dinoflagellates produce a suite of secondary metabolites, including ciguatoxins (CTXs), which bioaccumulate and are further biotransformed in fish and marine invertebrates, causing ciguatera poisoning when consumed by humans. This study is the first to compare the performance of the fluorescent receptor binding assay (fRBA), neuroblastoma cell-based assay (CBA-N2a), and liquid chromatography tandem mass spectrometry (LC-MS/MS) for the quantitative estimation of CTX contents in 30 samples, obtained from four French Polynesian strains of Gambierdiscus polynesiensis. fRBA was applied to Gambierdiscus matrix for the first time, and several parameters of the fRBA protocol were refined. Following liquid/liquid partitioning to separate CTXs from other algal compounds, the variability of CTX contents was estimated using these three methods in three independent experiments. All three assays were significantly correlated with each other, with the highest correlation coefficient (r2 = 0.841) found between fRBA and LC-MS/MS. The CBA-N2a was more sensitive than LC-MS/MS and fRBA, with all assays showing good repeatability. The combined use of fRBA and/or CBA-N2a for screening purposes and LC-MS/MS for confirmation purposes allows for efficient CTX evaluation in Gambierdiscus. These findings, which support future collaborative studies for the inter-laboratory validation of CTX detection methods, will help improve ciguatera risk assessment and management.  相似文献   
777.
Three mechanisms of oat milling were tested for laboratory-scale oat bran production. Oat bran consistent with AACC definition and commercially obtained product was generated with either roller-milling or impact-milling of groats, followed by sieving to retain larger particles. These bran preparations were enriched ≈1.7-fold in β-glucan and ash, 1.4-fold in protein, and 1.1-fold in lipid. Bran finishing made further enrichments in protein, β-glucan, and ash. Tempering oat (to 12% moisture for 20 min) improved bran yield from roller-milling nearly two-fold but had little effect on bran composition. Bran yield from the impact-type mill was significantly affected by grinding screen size. Oat bran obtained from a pearling mill was only slightly enriched in β-glucan and protein, but it was more heavily enriched in ash and oil than brans from roller or impact mills. The pearling mill isolated the outer layers of the groat directly, but because of its low β-glucan composition it did not meet the AACC definition of oat bran, indicating a relatively uniform distribution of β-glucan in the groat.  相似文献   
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