Interpretation of serum antibody response to Anoplocephala perfoliata in relation to parasite burden and faecal egg count

REASON FOR PERFORMING STUDY: Increased knowledge is needed to assist in the interpretation of presently available diagnostic techniques for infection by the tapeworm Anoplocephala perfoliata in horses. HYPOTHESIS: The suggested cut-off level of an A. perfoliata specific ELISA may not adequately reflect the actual infection level. Hence, faecal egg counts may be a more useful diagnostic test for individual horses than previously reported. METHODS: Eighty-four horses admitted for slaughter at a Danish abattoir were examined for the presence of A. perfoliata. The number of tapeworms, their stage of development and gross pathological mucosal lesions were recorded and compared with serum antibody responses and faecal egg counts. Faecal egg counts were determined in samples from A. perfoliata infected horses using a semi quantitative centrifugation/flotation technique. Blood samples collected at slaughter were analysed by ELISA to determine serum antibody levels against A. perfoliata 12/13 kDa excretory/secretory antigens. RESULTS: Macroscopically visible tapeworms were detected in 24 (29%) of the horses. The overall sensitivity of the faecal egg count was found to be 0.46; however, if the detection limit was increased to above 20 tapeworms, sensitivity increased to 0.89. There was a correlation of 0.71 between worm burden and egg count. The antibody levels correlated significantly with infection intensity despite a wide variation among horses with similar levels of infection. The optimal cut-off value was determined using receiver operating characteristic analysis. If cut-off was chosen at optical density (OD) = 0.7, sensitivity was 0.68 and specificity 0.71. CONCLUSIONS: Both diagnostic methods were capable of revealing potentially pathogenic infections, with the faecal egg count being more applicable on the individual horse level. POTENTIAL RELEVANCE: In the population of Danish horses investigated the serum ELISA test should be interpreted such that horses in need of anti-Anoplocephala treatment have an OD = 0.7 or above.     

Serum C-reactive protein concentration as an indicator of remission status in dogs with multicentric lymphoma

BACKGROUND: The acute-phase protein C-reactive protein (CRP) is used as a diagnostic and prognostic marker in humans with various neoplasias, including non-Hodgkin's lymphoma. OBJECTIVE: To evaluate if CRP could be used to detect different remission states in dogs with lymphoma. ANIMALS: Twenty-two dogs with untreated multicentric lymphoma. METHODS: Prospective observational study. Blood samples were collected at the time of diagnosis, before each chemotherapy session, and at follow-up visits, resulting in 287 serum samples. RESULTS: Before therapy, a statistically significant majority of the dogs (P = .0019) had CRP concentrations above the reference range (68%, 15/22). After achieving complete remission 90% (18/20) of the dogs had CRP concentrations within the reference range, and the difference in values before and after treatment was statistically significant (P < .001). CRP concentrations of dogs in complete remission (median, 1.91; range, 0.2-103) were significantly different (P = .031) from those of dogs with partial remission (median, 2.48; range, 0-89), stable disease (median, 1.77; range, 1.03-42.65), or progressive disease (median, 8.7; range, 0-82.5). There was profound variation of CRP measurements within each dog. CONCLUSIONS: CRP is useful in determining complete remission status after treatment with cytotoxic drugs. However, the individual variation between dogs means CRP concentration is not sufficiently different in other remission states to permit its use in monitoring progression of the disease. Greater reliability in determining remission status might be achieved by combining CRP concentration with other serum markers.     

A novel approach to estimating the competitive ability of Cirsium arvense in cereals using unmanned aerial vehicle imagery

Eight experiments were carried out in Denmark to determine the yield loss of spring barley due to Cirsium arvense in farmers' fields and to suggest and evaluate a novel approach for quantifying C. arvense infestation in large plots. Literature about the competitive ability of C. arvense is old, scattered and inconclusive, and existing models for estimating crop yield loss are based on data from North America. This study showed that C. arvense coverage could be quantified from unmanned aerial vehicle imagery using a manual image analysis procedure. This gave similar results as scoring the coverage. Yield loss of spring barley due to C. arvense infestation assessed at harvest was given by Y = 100·(1−exp(−0.00170·X)) where Y is the percentage of crop yield loss and X is the percentage of C. arvense coverage. The yield loss was much lower than estimates from models that have been developed in North America. It is speculated that the main reason for this is the later emergence of C. arvense than the crop due to lower soil temperatures in spring. Grain moisture increased linearly with C. arvense coverage: M = 0.0310·X where M is the proportional (%) increase in grain moisture and X is the proportion (%) of C. arvense coverage. Automated image analysis procedures are needed to estimate C. arvense coverage on field scales, and further experiments are needed to reveal whether the low competitive ability of C. arvense found in this study is representative for Northern Europe.     

Spatial integration of freshwater fish markets in the Northern Baltic Sea area

Freshwater fish species and Baltic salmon (Salmo salar) are important to small-scale fisheries in Finland and Sweden. The formerly local markets for these species have expanded as trade has been opened up to international competition. In this study we use cointegration analysis to test the spatial integration of freshwater fish markets in Finland and between Finland and Sweden. The analysed fish species are salmon, perch (Perca fluviatilis), pikeperch (Sander lucioperca), European whitefish (Goregonus lavaretus) and pike (Exos lucius), and the data covers ex-vessel prices from 1993 or 1995 to 2004. We found that the regional prices in Finland were cointegrated. This indicates that the prices are determined on a single market in Finland. Moreover, the study suggests that Finnish and Swedish markets in Baltic salmon, whitefish, pikeperch and perch were partially integrated, while integration of pike markets could not be found. The political implication is that an essential part of the local small-scale fisheries’ operational environment is determined outside the national borders.     

倾斜圆盘勺式玉米精密排种器的试验研究

为与铲式成穴器的结构特点相适应,选择倾斜圆盘勺式玉米精密排种器作为打穴播种机的排种机构。在分析分种勺结构特点和分种性能的基础上,通过试验确定了排种器倾角和转速对不同玉米种子分种性能的影响,并采用机械优化设计的方法对参数进行了优化组合。     

胰蛋白酶对叶蛋白水解作用的研究

以植物叶蛋白浓缩物为材料,用胰蛋白酶在不同条件下对其进行水解。结果表明,胰蛋白酶作用于植物叶蛋白,其最佳水解温度为４０℃;最佳水解ｐＨ值为９;水解程度随酶量和反应时间增加而增加;各种不同种类的植物叶蛋白在相同条件下被胰蛋白酶水解的程度基本一致,证明了植物叶蛋白易被动物体内蛋白酶分解。     

Genomewide association study reveals novel quantitative trait loci associated with resistance towards Septoria tritici blotch in North European winter wheat

Fungal diseases are a major constraint for wheat production. Effective disease resistance is essential for ensuring a high production quality and yield. One of the most severe fungal diseases of wheat is Septoria tritici blotch (STB), which influences wheat production across the world. In this study, genomewide association mapping was used to identify new chromosomal regions on the wheat genome conferring effective resistance towards STB. A winter wheat population of 164 North European varieties and breeding lines was genotyped with 15K single nucleotide polymorphism (SNP) wheat array. The varieties were evaluated for STB in field trials at three locations in Denmark and across 3 years. The association analysis revealed four quantitative trait loci, on chromosomes 1B, 2A, 5D and 7A, highly associated with STB resistance. By comparing varieties containing several quantitative trait loci (QTL) with varieties containing none of the found QTL, a significant difference was found in the mean disease score. This indicates that an effective resistance can be obtained by pyramiding several QTL.     

Effect of feeding intensity and milking system on nutritionally relevant milk components in dairy farming systems in the North East of England

There is increasing concern that the intensification of dairy production reduces the concentrations of nutritionally desirable compounds in milk. This study therefore compared important quality parameters (protein and fatty acid profiles; α-tocopherol and carotenoid concentrations) in milk from four dairy systems with contrasting production intensities (in terms of feeding regimens and milking systems). The concentrations of several nutritionally desirable compounds (β-lactoglobulin, omega-3 fatty acids, omega-3/omega-6 ratio, conjugated linoleic acid c9t11, and/or carotenoids) decreased with increasing feeding intensity (organic outdoor ≥ conventional outdoor ≥ conventional indoors). Milking system intensification (use of robotic milking parlors) had a more limited effect on milk composition, but increased mastitis incidence. Multivariate analyses indicated that differences in milk quality were mainly linked to contrasting feeding regimens and that milking system and breed choice also contributed to differences in milk composition between production systems.     

The effect of carbon dioxide under pressure against eggs of Ephestia kuehniella Zeller and adults of Stegobium paniceum (L.) and Oryzaephilus surinamensis (L.)

The efficacy of an atmosphere with a high content of carbon dioxide under a pressure of 5 and 10 bar against young eggs of Ephestia kuehniella Zeller (Lep.: Pyralidae) and adults of Stegobium paniceum (L.) (Col.: Anobiidae) and Oryzaephilus surinamensis (L.) (Col.: Cucujidae) was investigated. At a pressure level of 10 bar, a 100% mortality in eggs of E. kuehniella was obtained after 4 hours. Complete control was not obtained with the adult beetles, except for a 2 hour-treatment at 10 bar with individuals of S. paniceum, which not were offered protection. It is demonstrated that when working with an atmosphere of carbon dioxide under pressure of 10 bar for 2 hours, even a slight protection from food material will influence the mortality. The reason for these findings are discussed.     

Isolation of Cokeromyces recurvatus, initially misidentified as Coccidioides immitis, from peritoneal fluid in a cat with jejunal perforation.

Cokeromyces recurvatus, a zygomycete, was isolated by fungal culture from the peritoneal fluid of a cat with jejunal perforation secondary to intestinal lymphosarcoma. This organism has not been recovered previously from a veterinary patient. The tissue form of C. recurvatus is morphologically similar to those of Coccidioides immitis and Paracoccidioides brasiliensis and may be misdiagnosed as 1 of these organisms on the basis of cytologic or histopathologic specimens, particularly in geographic regions where these organisms are not endemic.