沙棘油脂

果实 沙棘果实由果肉（68%）、种子（23%）和果皮（7.75%）组成（Zadernowski et al.,1997）.Yang和Kallio（2001）最近发现,从中国、芬兰和前苏联（FSU）等地大量选择后采集的沙棘果实中23%～28%是种子,72%～77%是柔软的果肉/果皮.沙棘果实可提取3种油：种子油、果肉油和果皮油.不同于其他植物,沙棘果实的各部分都能合成并积累脂肪.有时果肉油和果皮油没有区别,因此统称为果实油或果肉油.沙棘叶也含油,这部分内容将在稍后部分进一步说明.     

Effects of grain type, roughage level and monensin level on finishing cattle performance

Interactions among grain type (grain sorghum, corn or wheat), roughage level and monensin level were studied in four feedlot trials using pen-fed crossbred yearling cattle. In Trial 1, cattle fed high-moisture corn (HMC) were more efficient (.1537 vs .1406 for gain/feed; P less than .01) than cattle fed dry-rolled grain sorghum (DRGS). As level (0, 3, 6, 9%) of dietary roughage was increased, feed efficiency (gain/feed) decreased (.1566, .1461, .1479, .1382; linear, P less than .01). In Trial 2, a grain type (DRGS; dry-rolled corn, DRC; dry-rolled wheat, DRW) x roughage level interaction was observed for daily gain and feed efficiency. Feed efficiency (gain/feed) was decreased when roughage was added to diets containing DRC (.1608 vs .1750) or DRGS (.1674 vs .1465), but not to the diet containing DRW (.1664 vs .1607). In trial 3, a grain type x roughage level x monensin level interaction (P less than .08) was observed for feed efficiency. The addition of 27.5 mg of monensin per kilogram of the 0% roughage-DRC diet tended to improve feed efficiency (.1633 vs .1531), but the addition of monensin to the 7.5% roughage-DRC diet tended to depress feed efficiency (.1476 vs .1575). The addition of either roughage (.1493 vs .1420) or monensin (.1500 vs .1413) to the DRW diet improved feed efficiency. In Trial 4, cattle fed a combination of 75% DRW and 25% DRC were more efficient (.1618 vs .1591; P less than .06) than cattle fed DRC. As level of roughage (0, 3.75, 7.5%) increased, feed efficiency decreased linearly (.1645, .1599, .1569; P less than .0001). Monensin had no effect on feed efficiency. The value of feeding roughage and monensin was variable both across grain types and within similar grain types.     

Comparison of radiographic osteoarthritis scores in dogs less than 24 months or greater than 24 months following tibial plateau leveling osteotomy

Radiographic osteoarthritis scores were determined in 60 dogs up to 3 years following tibial plateau leveling osteotomy. Radiographs taken immediately following surgery and at long-term follow-up 1 to 3 years later were evaluated by 2 certified radiologists using a modified 32-point osteoarthritis scale. Changes in osteoarthritis scores were evaluated by paired t-tests and regression analysis. Sub-groups of dogs were formed to evaluate if osteoarthritis scores changed differently for follow-up periods of < 24 months compared with those > 24 months. There was a significant increase in osteoarthritis score from post-operative to follow-up evaluations for all dogs studied. Regression analysis of the relationship of months after surgery to change in osteoarthritis score was not significant. These results indicate that osteoarthritis did progress following tibial plateau leveling osteotomy, but not in a linear fashion over time.     

Bioavailability as a Factor in Risk Assessment of Metal-Contaminated Soil

To accurately assess the risks of metal contaminants in soil, the bioavailability of the metals need to be considered. The bioavailable concentrations determined from homogenized, dried soils are not necessarily representative of in situ conditions of undisturbed field soils. In this study, we investigated the accumulation of metals in wheat (Triticum aestivum) grown in undisturbed contaminated (Pb, Zn, Cu, and Cd) soil cores, in relation to total soil, leachate, and diffusive gradients in thin films (DGT)-labile metal concentrations. Despite the fact that many of the samples contained metal concentrations above guideline values, no significant effects were observed on wheat growth. The bioavailability of metals in the most contaminated samples was estimated to be medium to low, possibly explaining why few effects were observed in the bioassay. For Cu, Zn, and especially for Pb, leachate and DGT-labile concentrations were better predictors of uptake by wheat than total concentrations based on correlations. It is suggested that DGT and leachate concentrations in combination with bioassays in undisturbed soil cores can be used to account for metal bioavailability in soil. These tests could be used during the ecological risk screening stage, in conjunction with total concentrations and guideline values to better estimate receptor exposure.     

Can Batesian mimicry help plants to deter herbivores?

Several authors have suggested that edible plants could avoid herbivory by mimicking olfactory cues of toxic plants. However, very few studies have been carried out to test this hypothesis. The aims of the present study were to identify the volatiles of three clover species and to test whether a species lacking chemical defences, such as red clover, could avoid being grazed by rabbits by mimicking the volatiles of the cyanogenic white clover. Two main volatiles were identified in all three clover species, and a further two volatiles were present in white clover only. Rabbits presented with a choice between white clover, red clover and red clover sprayed with white clover extract ate significantly more red clover than white or white-flavoured red clover. The results suggest that the volatiles of toxic plants could be used and exploited as a source of natural, safe and effective repellents to control the impact of pest herbivores on plants.     

Double haploids,markers and QTL analysis in vegetable brassicas

Double haploid (DH) plants of Brassica spp. can be produced via anther culture or culture of microspores. This paper reviews the uses of double haploids in crop improvement research in vegetable brassicas (B. oleracea). Applications of DH lines are described for breeding; construction of linkage maps; genetic analysis of quantitative traits and capturing genetic variation. The advantages and disadvantages of DH lines are discussed     

Longitudinal data collection of Mycobacterium avium subspecies Paratuberculosis infections in dairy herds: the value of precise field data

Longitudinal infection data on Mycobacterium avium subspecies paratuberculosis (MAP) was collected on three dairy farms in Northeastern United States during approximately 10 years. Precise data on animal characteristics and animal location within farm were collected on these farms. Cows were followed over time with regard to MAP status during biannual fecal and serum sampling and quarterly serum sampling. Approximately 13 000 serum samples, 6500 fecal samples and 2000 tissue samples were collected during these years. Prevalence of positive samples was 1.4% for serological samples, 2.2% in fecal samples and 16.7% in tissue samples. Infection dynamics of MAP was studied and resulted in a number of potential changes in our understanding of MAP infection dynamics. First, a high prevalence of MAP infection was observed in these herds due to lifetime follow up of cows, including slaughter. Second, two distinctly different infection patterns were observed, so called non-progressors and progressors. Non-progressors were characterized by intermittent and low shedding of MAP bacteria and a virtual absence of a humoral immune response. Progressors were characterized by continuous and progressive shedding and a clearly detectable and progressive humoral immune response. Strain typing of MAP isolates on the three farms identified on two of three farms a dominant strain type, indicating that some strains are more successful in terms of transmission and infection progression. Continuous high quality longitudinal data collection turned out to be an essential tool in our understanding of pathobiology and epidemiology of MAP infections in dairy herds.     

Yields of cultured Pacific oysters Crassostrea gigas Thunberg improved after one generation of selection

Parental families (G₀) in three lines of Pacific oysters were selected based on live weight and meat yields at harvest. The average live weight yield of progeny (G₁) from crossing G₀-selected lines in seven trials was 9.5% greater than that of nonselected control families and live weight yields were significantly greater (ANOVA, P<0.001) in four out of seven trials. The response to selection was greater if G₁ families were tested at the same site as their parents' selection site rather than at a different site, although this effect was only significant for G₁ families of cohort 5 (P<0.01) but not cohort 7 (P>0.05). A significant genotype×environment interaction affected yields in both cohort 5 and cohort 7 (ANOVA; P<0.001). In addition, correlation between the yields of the same families planted at both intertidal and subtidal sites was positive but weak (cohort 5, r=0.30; cohort 7, r=0.35), indicating that selection for high yield in one environment would likely result in a low correlated response in a different environment. Nonetheless, it was possible to identify six families in cohort 5 and four families in cohort 7 that were among the top 10 families at both sites. Further evaluation of families across a wider range of environments is needed to determine if it is possible to substantially improve yields by selecting “generalist” families that perform well along the whole Pacific coast, or whether it will be necessary to select lines that are suited to particular sites.