Soil organic carbon and nitrogen in aggregates in response to over seven decades of farmyard manure application

The study aimed to evaluate the effects of long-term fertilisation on soil aggregation and the associated changes in soil organic carbon (SOC) and nitrogen (N) pools in aggregates. The combined application of mineral fertiliser and manure improved soil aggregation, SOC and N content in aggregates, compared to manure or mineral fertiliser alone, and thus proved to be a suitable fertilisation strategy to increase C sequestration in agroecosystems.     

Prevalence of bovine viral diarrhea virus (BVDV) in persistently infected cattle and BVDV subtypes in affected cattle in beef herds in south central United States

The prevalence of bovine viral diarrhea virus (BVDV) in persistently infected (PI) cattle in beef breeding herds was determined using 30 herds with 4530 calves. The samples were collected by ear notches and tested for BVDV antigens using immunohistochemistry (IHC) and antigen capture enzyme-linked immunosorbent assay (ACE). Animals with initial positives on both IHC and ACE were sampled again using both tests and serums were collected for viral propagation and sequencing of a viral genomic region, 5′-untranslated region (5′-UTR) for viral subtyping. Samples were also collected from the dams of PI calves. There were 25 PI calves from 4530 samples (0.55%) and these PI calves were from 5 of the 30 herds (16.7%). Two herds had multiple PI calves and 3 herds had only 1 PI calf. Only 1 of the 25 dams with a PI calf was also PI (4.0%). The subtype of all the PI isolates was BVDV1b. Histories of the ranches indicated 23 out of 30 had herd additions of untested breeding females. Twenty-four of the 30 herds had adult cowherd vaccinations against BVDV, primarily using killed BVDV vaccines at pregnancy examination.     

正确的日常维护至关重要

在亚洲,企业的管理人员仍然普遍认为：设备有了故障时才有维修的必要。其实,在设备出现故障前对其进行检修维护,做到防微杜渐更为重要。现在,产品的服务期限比起几十年前会短一些,但良好的维护工作能极大地延长设备的寿命。     

Detection by real-time quaking-induced conversion (RT-QuIC), ELISA,and IHC of chronic wasting disease prion in lymph nodes from Pennsylvania white-tailed deer with specific PRNP genotypes

Chronic wasting disease (CWD) is a prion-mediated, transmissible disease of cervids, including deer (Odocoileus spp.), which is characterized by spongiform encephalopathy and death of the prion-infected animals. Official surveillance in the United States using immunohistochemistry (IHC) and ELISA entails the laborious collection of lymphoid and/or brainstem tissue after death. New, highly sensitive prion detection methods, such as real-time quaking-induced conversion (RT-QuIC), have shown promise in detecting abnormal prions from both antemortem and postmortem specimens. We compared RT-QuIC with ELISA and IHC for CWD detection utilizing deer retropharyngeal lymph node (RLN) tissues in a diagnostic laboratory setting. The RLNs were collected postmortem from hunter-harvested animals. RT-QuIC showed 100% sensitivity and specificity for 50 deer RLN (35 positive by both IHC and ELISA, 15 negative) included in our study. All deer were also genotyped for PRNP polymorphism. Most deer were homozygous at codons 95, 96, 116, and 226 (QQ/GG/AA/QQ genotype, with frequency 0.86), which are the codons implicated in disease susceptibility. Heterozygosity was noticed in Pennsylvania deer, albeit at a very low frequency, for codons 95GS (0.06) and 96QH (0.08), but deer with these genotypes were still found to be CWD prion-infected.     

Expression of adipokines and adipocytokines by epidural adipose tissue in cauda equina syndrome in dogs

BackgroundCompression of epidural adipose tissue (EAT) within the scope of cauda equina syndrome (CES) could lead to an enhanced expression of inflammatory mediators, possibly contributing to pain amplification in dogs.ObjectivesTo analyze expression of inflammatory adipo(‐cyto)kines within the EAT of dogs with CES.AnimalsClient‐owned dogs: 15 dogs with CES and 9 dogs euthanized for unrelated medical reasons (controls).MethodsProspective, experimental study. Epidural adipose tissue and subcutaneous adipose tissue were collected during dorsal laminectomy and used for real‐time quantitative polymerase chain reaction. Tissue explants were cultured for measurements of inflammation‐induced release of cytokines.ResultsResults show a CES‐associated upregulation of the cytokines tumor necrosis factor alpha (TNFα: mean ± SD: 18.88 ± 11.87, 95% CI: 10.90‐26.86 vs 9.66 ± 5.22, 95% CI: 5.29‐14.02, *: P = .04) and interleukin‐ (IL‐) 10 (20.1 ± 9.15, 95% CI: 14.82‐25.39 vs 11.52 ± 6.82, 95% CI: 5.82‐17.22, *: P = .03), whereas the expression of the adipokine leptin was attenuated in EAT of dogs with CES (3.07 ± 2.29, 95% CI: 1.80‐3.34 vs 9.83 ± 8.42, 95% CI: 3.36‐16.30, **: P = .007). Inflammatory stimulation of EAT explant cultures resulted in an enhanced release of IL‐6 (LPS: 5491.55 ± 4438, 95% CI: 833.7‐10 149; HMGB1: 1001.78 ± 522.2, 95% CI: 518.8‐1485; PBS: 310.9 ± 98.57, 95% CI: 228.5‐393.3, ***: P < .001).Conclusion and Clinical ImportanceExpression profile of inflammatory adipo(‐cyto)kines by EAT is influenced from compressive forces acting in dogs with CES and might contribute to amplification of pain.     

不同配置城市防护绿地中胡杨构型特征

应用枝系构型理论,研究了胡杨在克拉玛依市防护林中的分枝构型的特征,并重点针对3种配置类型:胡杨(Populus euphratica Oliv.)×沙枣(Elaeagnus angustifolia L.)、胡杨×银白杨(Populus alba L.)和胡杨×白榆(Ulmus pumila L.),分析了胡杨分枝构型在不同配置中的变化。结果表明:防护绿地中胡杨不同部位(树冠)构型格局中,各级分枝长度数值和各级分枝角度数值从上到下均表现为逐渐变大的趋势;不同配置类型对胡杨构型特征(主要表现在分枝角度和分枝长度两个指标)的影响存在显著差异,影响力大小依次为胡杨×银白杨、胡杨×白榆、胡杨×沙枣。     

不同技术措施对梭梭免灌造林成活率的影响

分别于2009年、2010年春季,在新疆古尔班通古特沙漠南缘选取了迎风坡、丘间平地、背风坡作为研究样地,采用不同的技术措施(保水剂、生根粉和液体地膜)进行梭梭免灌造林试验,以确定这些技术措施是否能有效提高古尔班通古特沙漠地区免灌造林成活率。结果表明:实施这些措施后,不同立地条件之间梭梭免灌造林成活率存在显著差异;水分是限制古尔班通古特沙漠梭梭免灌造林成活的关键因子,土壤理化性质对梭梭免灌造林成活率影响不显著;三种造林措施对梭梭免灌造林成活率有一定作用,但效果不显著。