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51.
Chimana Henry M. Muma John Bwalya Samui Kenny L. Hangombe Benard M. Munyeme Musso Matope Gift Phiri Andrew M. Godfroid Jacques Skjerve Eystein Tryland Morten 《Tropical animal health and production》2010,42(7):1541-1545
A cross-sectional study was conducted between January 2007 and February 2008 to estimate seroprevalence of brucellosis and
identify risk factors associated with Brucella infections in commercial cattle in three districts of Lusaka province (Chongwe, Luangwa, and Kafue; n = 849) and in one rural district from the Central province (n = 48). A total of 897 serum samples were randomly collected from 55 farms along with animal-level data such as sex, age,
and parity. Sera were screened for presence of anti-Brucella antibodies using the Rose Bengal test, and positive samples were confirmed using competitive enzyme-linked immunosorbent
assay. At the animal level, seroprevalence was estimated at 7.9% (95% CI = 4.4–11.4%) in the Lusaka province and 18.7% (95%
CI = 7.5–29.9%) for Chibombo district. Brucellosis seroprevalence varied according to district, with Chongwe district recording
the highest compared to other districts. Seroprevalence also varied according to sex with bulls (n = 96) having higher seroprevalence (12.5%; 95% CI = 3.8–21.1%) compared to females (8.1%; 95% CI = 4.6–11.6). Similarly,
seroprevalence varied according to age groups, with the age category 1–4 years recording the highest (10.7%). The study recorded
relatively low Brucella seroprevalence in commercial farms in Lusaka, compared to the traditional small-scale farms. We suggest that testing and
stamping out of infected animals is likely to improve the situation and significantly reduce the public health risk associated
with Brucella infections in animals. 相似文献
52.
Manuela Panzacchi John D.C. Linnell Claudia Melis Morten Odden John Odden Lucrezia Gorini Reidar Andersen 《Forest Ecology and Management》2010
During the last century the boreal forests of south-eastern Norway have been converted into patchworks of agricultural areas, clear-cuts and even-aged conifer monocultures. Even though Scandinavian forest ecosystems are strongly influenced by small mammals’ dynamics, the effects of anthropogenic changes on these communities are still debated. We conducted an extensive capture–mark–recapture study to examine the relative abundance and distribution of 11 species of small mammals during the reproductive season with respect to all available landscape-scale habitat types and fine-scale vegetation characteristics. 相似文献
53.
Carlos G. das Neves Swaantje Roth Espen Rimstad Etienne Thiry Morten Tryland 《Veterinary microbiology》2010
Herpesviruses of the genus Varicellovirus are known to infect and cause disease in a variety of ruminant species, but the impact of cervid herpesvirus 2 (CvHV2) in reindeer (Rangifer tarandus) is mostly unknown. Reindeer is a circum-polar species with a total estimated number of more than 5 million animals. Mortality may reach high values, as in northern Norway, especially in calves (37%; 2005–2006), and disease can potentially account for some of this mortality. CvHV2 has been isolated during a natural outbreak of infectious keratoconjunctivitis, indicating an etiologal link. Serological screening has shown that CvHV2 infection is prevalent in Northern Norway and experimental infection studies have demonstrated that viremia, latency and vertical transmission occur for CvHV2. The present review aims at summarizing current knowledge on the epidemiology, pathogenesis and molecular virology of CvHV2. 相似文献
54.
Jesper Møller Nielsen Mats H. Troedsson Morten Rønn Pedersen Anders Miki Bojesen Henrik Lehn-Jensen Walter W. Zent 《Journal of Equine Veterinary Science》2010
The objective of this study was to compare results from endometrial cytological and bacteriological examinations obtained by two different laboratories. One laboratory used endometrial swabs and the other endometrial biopsies for the examinations. A higher proportion of sterile, cytology positive cases were found in the laboratory using swabs (148/401 [37%] vs 12/237 [5%], P < .0001). In both laboratories it was found that positive cytology was less likely to occur when Escherichia coli was isolated than if other species were isolated. This tendency was significant in both laboratories (P < .05 vs P < .0001). 相似文献
55.
Oxidation of 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) by lactoperoxidase was found to be inhibited by tyrosine-containing random amino acid copolymers but not by tyrosine. Both electrostatic effects and polymer size were found to be important by comparison of negatively and positively charged copolymers of varying lengths, with poly(Glu, Tyr)4:1 ([E 4Y 1] approximately 40) as the strongest competitive inhibitor (EC 50 approximately 20 nM). This polymer did not form dityrosine in the presence of lactoperoxidase (LPO) and peroxide. Furthermore, incubation with tert-butyl hydroperoxide, as opposed to hydrogen peroxide, resulted in a peculiar long lag phase of the reaction between the redox intermediate compound II and [E 4Y 1] approximately 40, indicating a very tight association between enzyme and inhibitor. We propose that interactions between multiple positively charged areas on the surface of LPO and the polymer are required for optimal inhibition. 相似文献
56.
57.
Espen Sannes Sørensen Constantin Jansen Susanne Windju Jose Crossa Anna Kristina Sonesson Morten Lillemo Muath Alsheikh 《Plant Breeding》2023,142(1):41-53
Genomic selection is a promising breeding methodology that could increase selection accuracy and intensity and reduce generation interval. As the cost of genotyping decreases, it will be important to optimize training populations for costly phenotypic experiments for many complex traits. The aim of this research was to evaluate different optimization strategies, by using historical data from the Norwegian oat breeding programme at Graminor. In this paper, we focus on the optimization criteria: genetic diversity, phenotypic variance and genetic similarity between the training and testing populations. The four training population strategies—prediction core, diversity core, phenotypic selection and random selection—were applied to an oat candidate population of 1124 lines. An independent testing population was used to calculate the mean prediction abilities for the traits days to heading and plant height. Moreover, the strategies were tested in three independent wheat populations. The results showed that prediction core was the most promising strategy to select training populations with high genetic similarity to the testing set, high genetic diversity, and high phenotypic variance, which resulted in higher prediction ability across population sizes and traits. 相似文献
58.
59.
A model for spatial wood density gradients in Norway spruce stems and stochastic between-stem dissimilarities for basic and dry density 总被引:1,自引:1,他引:0
Density is a fundamental softwood quality trait. The aim of this paper is to identify a spatial model for wood density variation in spruce stems, with the main focus on basic density. Six thousand 20-mm-wide cubes systematically sampled from 85 trees in western Norway were analysed. The overall radial density pattern was the J shape with local maximum in the pith and increasing density outwards from a minimum at some distance from the pith. The minimum appeared closer to the pith further up in the tree. The stochastic nature of the six tree-wise parameters defining density gradients from pith to surface and from base to top was analysed and described. The results provide information needed to simulate density variation inside stems and between stems in a population. Considering the fundamental influence of density on a range of wood traits, such simulation should be of great significance for scientific and industrial analyses. 相似文献
60.
Rohn S Buchner N Driemel G Rauser M Kroh LW 《Journal of agricultural and food chemistry》2007,55(4):1568-1573
Flavonoids are an important constituent of the human diet. In recent years, they have gained much attention due to their physiological properties, leading to an enormous increase in research on cancer prevention and reduction of cardiovascular diseases. Unfortunately, there is limited information about the fate of flavonoid glycosides during thermal treatment such as cooking, frying, roasting, etc. Such processing techniques may have an impact on the flavonoid structure, resulting in changes of the bioavailability and activity of the flavonoids. In this study, the stability of selected model and onion quercetin glycosides under roasting conditions (180 degrees C) was determined. The influence of the kind and position of the sugar moiety was investigated. As onions contain large amounts of quercetin glycosides and are often subject to thermal processes in food production, their major glycosides were isolated using counter current chromatography and roasted. The thermal treatment led to a degradation of the quercetin glycosides. The main product is the aglycone quercetin, which remained stable during further roasting. During the roasting process of the quercetin diglucoside isolated from onion, the formation of a monoglycoside as an intermediate product was observed. This underlined that the stability of the glycosides is dependent on the kind and position of the sugar moiety. 相似文献