Seroprevalence and Risk Factors for Leptospira Seropositivity in Beef Cattle,Sheep and Deer Farmers in New Zealand

Leptospirosis is a global zoonosis that in New Zealand affects primarily people occupationally exposed to livestock. The objective of this study was to estimate the seroprevalence of five Leptospira serovars in farmers working on cattle, sheep and deer farms that had the serological status of animals previously assessed and to identify risk factors for farmer seropositivity. A total of 178 farmers from 127 properties participated in the study. Blood samples were tested using the microscopic agglutination test (MAT) for the presence of antibodies to Leptospira. Samples with a MAT titre ≥48 were considered seropositive. Using Bayesian statistical analysis, the median seroprevalence of Leptospira, all serovars combined, was estimated to be 6.6% (95% probability interval (PI) 3.6–10.9%). Risk factors associated with seropositivity were assisting deer or cattle calving, farming deer, having ≥25% of flat terrain and high abundance of wild deer on farm, while high possum abundance on farm was negatively associated with seropositivity. No association was observed between farmer serostatus and previously recorded livestock serology. Leptospira seropositivity was associated with influenza‐like illness of farmers (RR = 1.7; 95% PI 1.0–2.5). Assuming a causal relationship, this suggested an annual risk of 1.3% (95% PI 0.0–3.0%) of influenza‐like illnesses due to Leptospira infection in the population of farmers. The association between seropositivity and disease can be used to estimate the public health burden of leptospirosis in New Zealand. Identifying and understanding risk factors for Leptospira seropositivity can inform preventive measures, hence contributing to the reduction of leptospirosis incidence in farmers.     

基于关系营销的农资产品终端销售策略分析

介绍了关系营销的内涵,基于对农资终端销售现存问题的分析,提出了关系营销在农资终端销售中的具体实施策略。     

果园生态环境无线传感器网络监测系统

针对目前果园生产管理主要靠人工完成的现状,提出并开发了一套可靠的果园监测系统。经调试及测试表明,该系统能够实现小规模果园环境的远程实时监控,为实现果园生产管理自动化及数字化提供了参考。     

Retrospective Study: The association of blood lactate concentration with outcome in dogs with idiopathic immune‐mediated hemolytic anemia: 173 cases (2003–2006)

Objective – To determine the association of blood lactate with outcome and response to transfusion therapy in dogs with idiopathic immune‐mediated hemolytic anemia (IMHA). Design – Retrospective study. Setting – Urban veterinary small animal emergency hospital. Animals – One hundred and seventy‐three client‐owned dogs with IMHA. Interventions – None. Measurements and Main Results – Serial blood lactate concentration, therapeutic interventions, and outcome were recorded. Nonsurvivors were defined as those that died or were euthanized. One hundred and thirty‐three dogs (77%) survived, 35 (20%) were euthanized, and 5 (3%) died. One hundred forty‐five dogs (84%; 145/173) had a lactate concentration above the laboratory reference interval [0.46–2.31 mmol/L] on presentation. Blood lactate at presentation was higher in the nonsurvivors (median 4.8 mmol/L; 0.5–13.6) compared with survivors (median 2.9 mmol/L; 0.3–13.2) (P<0.01). All dogs presenting with hyperlactatemia that normalized (<2.0 mmol/L) within 6 hours of admission survived, whereas, 71% of dogs that had a persistent hyperlactatemia at 6 hours survived (P=0.034). Lactate was positively correlated with age, BUN, and alkaline phosphatase, and inversely correlated with PCV. Receiver operating curve analysis for lactate concentration at admission as a test for outcome had an area under the curve of 0.69 with an optimal lactate cutoff concentration of 4.4 mmol/L correctly predicting outcome 73% of the time (sensitivity 60%, specificity 77%). Conclusions – Lactate concentration at presentation was significantly higher in nonsurvivors than survivors. Lactate was significantly correlated with previously reported outcome variables but lactate concentration at admission, as a predictor for outcome was less than optimal. However, serial lactate concentration measurements may be more predictive as patients with persistent hyperlactatemia 6 hours after admission were less likely to survive. Prospective studies evaluating serial lactate concentration while controlling for other variables may provide further insight into lactate measurement as a prognostic indicator in animals with IMHA.     

一个新的大豆类受体蛋白激酶基因rlpk2的克隆及其结构特征

植物类受体蛋白激酶在细胞生长及对环境胁迫反应方面起着非常重要的作用.本文报告用RACE方法(快速扩增cDNA末端)扩增一个新的大豆类受体蛋白激酶基因rlpk2的全长cDNA.根据RACE的结果,我们克隆了rlpk2的cDNA,其序列信息已经提交到GenBank(Accession No.AY687391).经初步分析,rlpk2编码产物为LRR型类受体蛋白激酶.     

Development and evaluation of a guayule seed harvester

Guayule flowers continuously and seeds mature at different times; thus, a harvesting method that is gentle and non-destructive is required. The main objective of this study was to develop a simple but effective harvesting system capable of dislodging and collecting seed without damaging the plant. A single-row guayule seed harvester was developed after investigating different methods of seed dislodgement and collection. The harvester consisted of a seed dislodgement mechanism that removes seeds by vibration of spring steel rods. An axial flow fan placed directly over the vibrating rods catches the seed before it falls to the ground. The seed is then conveyed by the air stream through an inflatable canvas tube to a collection bin. The design and development of the seed catching system was based on terminal velocity of the unthreshed seed. Vibration frequencies ranging from 9.9 to 14.5 Hz and amplitude from 4 to 5.5 cm were used to test the harvester in the field. Harvested seed was analysed for percentages of clean seed in the harvested material, seed loss and immature seeds harvested. The performance of the machine was evaluated based on harvesting capacity and efficiency. Guayule seed harvested by the machine ranged from 1.73 to 7.18 kg/ha and harvest efficiency varied from 77 to 91%. The percentage of immature seeds removed from the crop during mechanical harvesting was as low as 0.1%. Although there was a trend for better efficiency from higher vibration frequencies, the variation was not significant. Nearly 21% of the harvested sample was clean which was much higher than that reported by other researchers. The harvester can be converted into a multiple row machine to increase its capacity.     

公路病害及病害处治

对常见的公路病害种类、危害进行了预防与外治，并对公路翻浆水毁的预防与处治也进行了分析。     

杜洛克猪和大白猪作终端父本的杂交效果比较研究

为比较杜洛克和大白猪作终端父本的杂交效果，进行了杜×长大、大×长大、长×大的比较试验，测定了不同组合的生长速度、饲料转化率、胴体品质和肉质。采用综合评定指数评定结果表明，大×长大组的主要经济性状优于杜×长大组。根据本次试验和国内外大量试验结果，作者论述了利用大白猪，特别近几年从英国引进的大白猪作终端父本生产商品瘦肉猪，逐步替代传统的杜×长大组合的可能性