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French AT Ogden R Eland C Hemani G Pong-Wong R Corcoran B Summers KM 《Veterinary journal (London, England : 1997)》2012,193(1):283-286
The Cavalier King Charles Spaniel (CKCS) is prone to severe early onset mitral valve disease. In this study, 36 purebred CKCS dogs were evaluated for mitral valve murmur and divided into early and late onset groups. A genome-wide genetic approach was used to assess whether the condition is determined by a small number of genetic factors. There were no regions of highly discrepant homo/heterozygosity in the two groups. Similarly, there was no evidence for loci associated with mitral valve murmur in a genome-wide association study. This analysis suggests that familial occurrence of mitral valve murmur in the CKCS breed is not due to a single major gene effect, indicating that breeding strategies to eliminate the disease cannot be based on genotype information at this time. 相似文献
54.
Using historical seed catalogues in combination with molecular fingerprinting data, diversity trends of lettuce, representing an important vegetable with active breeding programmes, were studied. Seed catalogues originating from France and the Netherlands from five different decades, the earliest dating from the 1840s, were checked for the occurence of lettuce cultivars. A total of 225 catalogues, with 7,311 records of lettuce, representing 878 different cultivars were found. The number of unique cultivars on offer by French and Dutch companies showed a small continuous increase until the 1960s, after which the number of cultivars on offer more than doubled to a total of 534 in the 1990s. Only a relatively small overlap between France and the Netherlands in the range of cultivars offered was observed. The 1960s appeared to be a period with many changes: the lowest genetic diversity in lettuce cultivars was found for this decade, whereas after the 1960s the number of companies supplying lettuce seeds reduced dramatically. The percentage of companies in a decade offering an identical cultivar decreased over time, and in the 1990s almost all cultivars were unique to only a single company. The possible relations of the observed trends with the developments in plant variety protection and in the plant breeding industry are discussed. 相似文献
55.
Kate Bottoms Zvonimir Poljak Robert Friendship Rob Deardon Janet Alsop Cate Dewey 《Canadian journal of veterinary research》2013,77(4):241-253
Risk-based surveillance is becoming increasingly important in the veterinary and public health fields. It serves as a means of increasing surveillance sensitivity and improving cost-effectiveness in an increasingly resource-limited environment. Our approach for developing a tool for the risk-based geographical surveillance of contagious diseases of swine incorporates information about animal density and external biosecurity practices within swine herds in southern Ontario. The objectives of this study were to group the sample of herds into discrete biosecurity groups, to develop a map of southern Ontario that can be used as a tool in the risk-based geographical surveillance of contagious swine diseases, and to identify significant predictors of biosecurity group membership. A subset of external biosecurity variables was selected for 2-step cluster analysis and latent class analysis (LCA). It was determined that 4 was the best number of groups to describe the data, using both analytical approaches. The authors named these groups: i) high biosecurity herds that were open with respect to replacement animals; ii) high biosecurity herds that were closed with respect to replacement animals; iii) moderate biosecurity herds; and iv) low biosecurity herds. The risk map was developed using information about the geographic distribution of herds in the biosecurity groups, as well as the density of swine sites and of grower-finisher pigs in the study region. Finally, multinomial logistic regression identified heat production units (HPUs), number of incoming pig shipments per month, and herd type as significant predictors of biosecurity group membership. It was concluded that the ability to identify areas of high and low risk for disease may improve the success of surveillance and eradication projects. 相似文献
56.
Schirra M Palma A D'Aquino S Angioni A Minello EV Melis M Cabras P 《Journal of agricultural and food chemistry》2008,56(2):455-460
The present study investigated the influence of a hot water dip (HWD) for 2 min at 50 degrees C, a standard and effective treatment for postharvest decay control of citrus fruit, on the nutritional and health-related properties of kumquats. The results show that most of the parameters examined, including titratable acidity, soluble solids content, maturity index, glucose, fructose, sucrose, ascorbic acid, dehydroascorbic acid, alpha- and gamma-tocopherols, beta-carotene, zeaxantin, rhoifolin, and antioxidant activity, were not significantly affected by treatment. The levels of beta-cryptoxanthin, narirutin, and total flavonoids increased after HWD, whereas lutein and total phenols decreased. The concentration of the essential oil and the relative percentage of the individual components of the essential oil were not affected by HWD except for the minor compound p-menta-1,5-dien-1-ol, which increased after HWD. After storage, lower levels of glucose, total sugars, beta-carotene, beta-cryptoxanthin and lutein were recorded in HWD fruit. A decrease in antioxidant activity and increases in alpha-tocopherol and total vitamin E were found both in control and HWD fruit. The influence of HWD at 50 degrees C for 2 min on individual nutraceuticals and health-related properties was thus generally low and may depend on storage conditions. 相似文献
57.
Mateo Anson N van den Berg R Havenaar R Bast A Haenen GR 《Journal of agricultural and food chemistry》2008,56(14):5589-5594
Grain is an important source of phytochemicals, which have potent antioxidant capacity. They have been implicated in the beneficial health effect of whole grains in reducing cardiovascular disease and type 2 diabetes. The aim of the present study was to identify the most important antioxidant fractions of wheat grain. It was found that the aleurone content of these fractions was highly correlated with the antioxidant capacity of the fractions (r = 0.96, p < 0.0001). Ferulic acid appeared to be the major contributor to the antioxidant capacity in fractions with higher antioxidant capacity. The contribution of protein was rather limited. It was concluded that the antioxidant potency of wheat grain fractions is predominantly determined by aleurone content, which can be attributed to the presence of relatively large amounts of phenolic compounds, primarily ferulic acid. 相似文献
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Ceratocystis albofundus is a recently described pathogen infectingAcacia mearnsii in South Africa, and it causes a disease known as Ceratocystis wilt. Symptoms of the disease include die-back, gummosis and
wilting of infected trees. In order to select trees tolerant to this fungus, susceptibility tests were conducted on trees
representing fourteen families ofA. mearnsii. A virulent isolate ofC. albofundus was selected and inoculated into the stems of twelve-month-old plants in a plantation. Lesion lengths, in the bark, and disease
development were assessed after 6 weeks. All fourteen families ofA. mearnsii were susceptible to infection byC. albofundus. Considerable variation was, however, noticed between individual trees within the same family and the incorporation of disease
tolerant trees into breeding programmes is proposed. 相似文献
60.
Jann Th. Martinsohn Paul Raymond Trey Knott Kevin A. Glover Einar Eg Nielsen Lars Bonde Eriksen Rob Ogden John Casey Jordi Guillen 《Fish and Fisheries》2019,20(2):391-401
Evidence from DNA‐analysis is commonplace in human criminal investigations, and while it is increasingly being used in wildlife crime, to date, its application to control and enforcement activities in fisheries and aquaculture has only been sporadic. Contemporary DNA‐analysis tools are capable of addressing a broad range of compliance issues, species identification, mislabelling of fish products, determining the origin of catches and the farm of origin of aquaculture escapees. Such applications have the potential to ensure traceability along the fish product supply chain and to combat consumer fraud and Illegal, Unreported and Unregulated fishing. Nevertheless, DNA‐analysis is not yet used routinely in investigations into compliance with fisheries and aquaculture legislation. One potential reason for this is that DNA‐analysis techniques may have been regarded as too expensive. However, costs have plummeted over the past decade prompting us to objectively assess whether the costs associated with routine use of DNA‐analysis techniques for fisheries and aquaculture control and enforcement activities do constitute an impediment. Based on a number of recent fisheries and aquaculture compliance investigations that incorporated DNA‐analysis, our results indicate that the use of genetic analysis was justified and worthwhile in all cases examined. We therefore conclude that the costs associated with DNA‐analysis do not represent a barrier to the routine adoption of DNA‐analysis techniques in fisheries and aquaculture compliance investigations. Thus, control and enforcement agencies should be encouraged to use such techniques routinely. 相似文献