Effect of dietary Schizochytrium microalga oil and fish oil on plasma cholesterol level in rats

The purpose of the study was to test the hypothesis that the dietary oils with different content of n‐3 polyunsaturated fatty acids (PUFA) eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) affect plasma lipid level in rats in a different degree. The diets with 6% of fish oil (FO) and Schizochytrium microalga oil (SchO; EPA+DHA content in the diets 9.5 + 12.3 and 2.6 + 29.5% of the sum of total fatty acids, respectively) were used; the diet with 6% of safflower oil (high content of n‐6 PUFA linoleic acid, 65.5%; EPA+DHA content 0.7 + 0.9%) was used as a control. The difference between FO and SchO was established only in the case of plasma triacylglycerol (TAG) level: plasma TAG of the FO‐fed rats did not differ from the control rats (p > 0.05), while SchO decreased (p < 0.05) plasma TAG to 46% of the control. On the other hand, FO and SchO decreased (p < 0.05) total plasma cholesterol (TC) in rats in the same extent, to 73% of the control. Regarding the underlying mechanisms for the TC decrease, both SchO and FO up‐regulated hepatic Insig‐1 gene (181 and 133% of the control; p < 0.05), which tended (p = 0.15 and p = 0.19 respectively) to decrease the amount of hepatic nSREBP‐2 protein (61 and 66% of the control). However, neither SchO nor FO influenced hepatic 3‐hydroxy‐3‐methyl‐glutaryl‐CoA reductase gene expression (p > 0.05); SchO (but not FO) increased (p < 0.05) low‐density lipoprotein receptor mRNA in the liver. It was concluded that the decrease of total plasma cholesterol might be caused by an increased cholesterol uptake from plasma into the cells (in the case of SchO), but also by other (in the present study not tested) mechanisms.     

Surveys on Coxiella burnetii infections in Swedish cattle,sheep, goats and moose

Background

Q fever is a zoonotic disease caused by the bacterium Coxiella burnetii. Prevalence data in ruminant species are important to support risk assessments regarding public and animal health. The aim was to investigate the presence of or exposure to C. burnetii in cattle, sheep, goats and moose, and to compare two enzyme-linked immunosorbent assays (ELISAs). National surveys of antibodies against C. burnetii were performed for dairy cattle (n=1537), dairy goats (n=58) and sheep (n=518). Bovine samples consisted of bulk milk, caprine of pooled milk, and ovine of pooled serum. Antibodies were investigated in moose samples (n=99) from three regions. A one-year regional cattle bulk milk survey was performed on the Isle of Gotland (n=119, four occasions). Cattle, sheep and goat samples were analysed with indirect ELISA and moose samples with complement fixation test. For the sheep, goat, and parts of the cattle survey, samples were run in parallel by ELISAs based on antigens from infected ruminants and ticks. Bulk milk samples from the regional cattle survey and vaginal swabs from a subset of the sheep herds (n=80) were analysed for the agent by polymerase chain reaction. Spatial clustering was investigated in the national cattle survey.

Results

The prevalence of antibodies in dairy herds was 8.2% with large regional differences. High risk clusters were identified in the southern regions. The prevalence among dairy herds on the Isle of Gotland varied from 55.9% to 64.6% and 46.4% to 58.9.0% for antibodies and agent, respectively, overall agreement between agent and antibodies was 85.2%. The prevalence of antibodies in sheep was 0.6%, the agent was not detected the vaginal swabs. Antibodies were not detected in goats or moose, although parts of the moose samples were collected in an area with high prevalence in cattle. The overall agreement between the two ELISAs was 90.4%.

Conclusions

The prevalence of antibodies against C. burnetii in dairy cattle in Sweden shows large regional differences. The results suggest that C. burnetii is a rare pathogen among Swedish moose, dairy goat and sheep. ELISAs based on ruminant and tick antigen performed in a similar manner under Swedish conditions.     

Reproductive characteristics in female Swedish moose (Alces alces), with emphasis on puberty,timing of oestrus,and mating

Background

The moose (Alces alces) is an intensively managed keystone species in Fennoscandia. Several aspects of reproduction in moose have not been fully elucidated, including puberty, timing of mating and oestrus, and the length of the oestrus period. These aspects are relevant for an adaptive management of moose with respect to harvest, population size, demography and environmental conditions. Therefore, an investigation of female moose reproduction was conducted during the moose-hunting period in southern Sweden from 2008 to 2011.

Results

A total of 250 reproductive organs and information on carcass weight and age was collected from four different hunting areas (provinces of Öland, Småland, Södermanland, and Västergötland) in southern Sweden. The results showed that puberty in female moose varied with carcass weight, age, and time of season. The period for oestrous/mating lasted from about mid September to the beginning of November.

Conclusions

The oestrus period (predominantly for heifers) is longer than previously reported and was not finished when the hunting period started. Sampling the uterine cervix to detect spermatozoa was a useful method to determine if mating had occurred. To avoid hunting of moose during oestrus, we suggest that the hunting period should be postponed by at least 14 days in southern Sweden.     

Radiography,Computed Tomography and Magnetic Resonance Imaging of Craniofacial Structures in Pig

The pig has recently become popular as a large animal experimental model in many fields of biomedical research. The aim of this study is to evaluate the basic anatomical structures in the head region of the pig to lay the groundwork for its practical clinical usage or pre‐clinical research in the future. We used three different diagnostic imaging methods: radiography, computed tomography (CT) and magnetic resonance imaging (MRI). The analysis showed that radiographic imaging is suitable only for general evaluation of the facial area of the pig skull. CT images showed excellent spatial definition of bony structures of the whole craniofacial area, and MRI images revealed fine soft tissue details. Radiography is preferentially suited to general assessment of bone structures of the facial skeleton; however, the thick layer of adipose tissue in the craniofacial region of the pig makes the imaging of some parts difficult or even impossible. CT is useful for revealing morphological details of mineralized tissues, whereas MRI is more suitable for soft tissue analysis and the detection of subtle pathologic changes in both bone and soft tissues. Therefore, before using pigs as an experimental model in craniofacial research, it is necessary to evaluate the suitability and disadvantages of potential imaging methods and how appropriate they are for accurate visualization of desired structures.     

Can the structure of dormant cambium and the widths of phloem and xylem increments be used as indicators for tree vitality?

We investigated the structure and width of the dormant cambium and of the increments of phloem and xylem of Quercus robur to estimate their potential as indicators for tree vitality. The samples were taken from three woodlands, two in Slovenia [Krakovo forest (KRA) and Murska Suma (MUS)] and one in Croatia [Kobiljak (KOB)], with reported tree decline. The number of dormant cells seems to reflect the initial capacity of the cambium to accomplish cell division. With the exception of two trees at KRA, cell production was always higher on the xylem side than on the phloem side. The annual phloem increments were narrower, less variable among trees and with clear lower and upper limits. With increased cambial cell productivity, the share of the xylem in the total annual radial increment increased following a curvilinear function. In trees with an annual radial increment >3.5 mm, the xylem size represented more than 90 % of the total radial growth. The anatomical variables analyzed show that the most limiting environmental conditions seem to prevail at KRA, whereas the conditions at MUS seem to be most favorable in terms of radial growth. Analysis of the width and structure of xylem and phloem increments, the number of dormant cambial cells and their inter-relationships can provide additional information on the vitality of oaks.     

Factors affecting the persistence of traditional agricultural landscapes in Slovakia during the collectivization of agriculture

Collectivization of agriculture (1950s–1970s) was one of the most important periods in landscape development in Slovakia. Traditionally managed agricultural landscapes, that covered more than half of the Slovak territory, were transformed into large-scale fields and only fragments of traditional agricultural landscapes survived. We mapped the remaining traditional agricultural landscapes using aerial photos and historical maps. We then statistically analyzed the various geographical factors and their influence on the transformation process of traditional and collectivized fields, i.e., slope steepness, soil fertility, distance from settlements and isolation from regional capital cities. The comparison was performed using classification tree analysis. We constructed a set of decision rules that explain why fields were managed traditionally or collectivized. Our findings show that traditional agricultural fields were more likely to persist on steep terrain, less fertile soils, and on locations that were closer to the settlements, but more isolated from the regional capital cities. Steepness played the most important role: small-scale fields located on steep areas were not accessible to heavy machinery and therefore, frequently survived the collectivization. We show that the selected geographical factors are good explanatory variables for the collectivization of arable fields and orchards. For vineyards and grasslands, however, the explanatory power of the selected geographical factors is lower, and we suspect that other factors, not depicted in the analysis play an important role.     

Flowering estimation in apple orchards by image analysis

Tree-specific management practice related to individual tree physiological condition is necessary for higher quality and quantity in apple fruit production. Detection of apple flowering abundance based on analysis of HSL (hue, saturation, luminance) images was used to estimate the number of flower clusters (FC) of individual trees in a high density apple orchard. The image acquisition was performed with a still camera and an industrial color camera during the day and night. The FC estimation algorithm included HSL thresholding with parameter optimization. Three hypothetical, tree-specific management practices (sprayings) were assumed, using >25, >50 and >100 FC thresholds to carry out the practice. When an industrial camera was used for image acquisition during the daytime and hypothetical spraying was done by on/off criterion >100 FC per tree, 10 % incorrect executions were identified. Comparable FC counting performance was achieved by using a still camera or an industrial camera.     

Forest management and forest state in southern Sweden before and after the impact of storm Gudrun in the winter of 2005

About three times the annual cut in southern Sweden (Götaland) was damaged by the storm Gudrun in January 2005, i.e. almost as much as the normal annual cut for all of Sweden. To establish any differences in forest management and state before and after the storm, measures such as growing stock volume, age-class distribution, and species composition were analyzed within the damaged area. As a reference the situation before and after the storm within the area in Götaland not damaged by the storm was also analyzed. For all analyses, sample plots from the Swedish National Forest Inventory were used. Results based on mean values for the years 2000–2004/2005–2009 showed that the total growing stock for the damaged area decreased by approximately 30 million m³ after the storm. This was mainly caused by a decrease in Norway spruce (Picea abies (L.) H. Karst). Annual growth for pine, spruce, and deciduous trees decreased by 1.8 million m³ in the damaged area. This mainly included stands already thinned and not, as expected, in the stands ready for final felling. Also, the proportional area within each of the age classes 21–40, 41–60, and 61–80 years decreased. The storm led to an increased area in immediate need of precommercial thinning. No changes in choice of species when regenerating could be observed. Furthermore, only marginal adaptation by forest owners to future risk of wind throw could be detected.     

Evaluation of mulched drip irrigation for cotton in arid Northwest China

Field experiments were conducted in arid Southern Xinjiang, Northwest China, for 3 years to evaluate sustainable irrigation regimes for cotton. The experiments involved mulched drip irrigation during the growing season and flood irrigation afterward. The drip irrigation experiments included control experiments, experiments with deficit irrigation during one crop growth stage, and alternative irrigation schemes in which freshwater was used during one growth stage and relatively saline water in the others. The average cotton yield over 3 years varied between 3,575 and 5,095 kg/ha, and the irrigation water productivity between 0.91 and 1.16 kg/m³. Crop sensitivities to water stress during the different growth stages ranged from early flowering-belling (most sensitive) > seedling > budding > late flowering-belling (least sensitive), while sensitivities to salt stress ranged from late flowering-belling > budding > seedling > early flowering-belling. Although mulched drip irrigation during the growing season caused an increase in salinity in the root zone, flood irrigation after harvesting leached the accumulated salts to below background levels. Numerical simulations, based on the 3-year experiments and extended by another 20 years, suggest that mulched drip irrigation using alternatively fresh and brackish water during the growing season and flood irrigation with freshwater after harvesting is a sustainable irrigation practice that should not lead to soil salinization.