Temporary Turnout for Free Exercise in Groups: Effects on the Behavior of Competition Horses Housed in Single Stalls

In Germany, most competition horses are housed in single stalls and free exercise is not permitted in many cases. The reason for not allowing free exercise is mostly the risk of injury. Additionally, opinions exist that the horses’ demand for exercise is fulfilled by training and that the horses’ willingness to perform is negatively influenced by free exercise. In the present study, three turnout practices were investigated with regard to their effect on the behavior of four horses: daily training without free exercise (no turnout), 2-hour turnout (for free exercise) before training, and 2-hour turnout after training. The aim of this study was to determine any differences in the horses’ behavior between the three treatments. The horses’ behavior in the stable was observed through video recordings. The behavior during turnout was observed directly and during training was evaluated by the riders with the aid of a questionnaire. Additionally, the distance covered during turnout was measured by Global Positioning System devices. The behavior within the stall was more restless in the treatment without turnout—which became apparent in significantly more frequent changes between behaviors as compared with the treatments with turnout. The results of Global Positioning System measurement during turnout showed a significantly shorter distance covered when horses were trained before they were turned out compared with turnout before training. If the horses were turned out after training, they also showed less trotting and cantering and more dozing. The horses’ willingness to perform was not significantly different between the three treatments.     

Breeding with resistant rams leads to rapid control of classical scrapie in affected sheep flocks

ABSTRACT: Susceptibility to scrapie, a transmissible spongiform encephalopathy in sheep, is modulated by the genetic make-up of the sheep. Scrapie control policies, based on selecting animals of resistant genotype for breeding, have recently been adopted by the Netherlands and other European countries. Here we assess the effectiveness of a breeding programme based on selecting rams of resistant genotype to obtain outbreak control in classical scrapie-affected sheep flocks under field conditions. In six commercially-run flocks following this breeding strategy, we used genotyping to monitor the genotype distribution, and tonsil biopsies and post-mortem analyses to monitor the occurrence of scrapie infection. The farmers were not informed about the monitoring results until the end of the study period of six years. We used a mathematical model of scrapie transmission to analyze the monitoring data and found that where the breeding scheme was consistently applied, outbreak control was obtained after at most four years. Our results also show that classical scrapie control can be obtained before the frequency of non-resistant animals is reduced to zero in the flock. This suggests that control at the national scale can be obtained without a loss of genetic polymorphisms from any of the sheep breeds.     

GC-based analysis of plant stanyl fatty acid esters in enriched foods

Approaches for the capillary gas chromatographic (GC) based analysis of intact plant stanyl esters in enriched foods were developed. Reference compounds were synthesized by enzyme-catalyzed transesterifications. Their identities were confirmed by means of mass spectrometry. Using a medium polar trifluoropropylmethyl polysiloxane stationary phase, long-chain plant stanyl esters could be separated according to their stanol moieties and their fatty acid chains. Thermal degradation during GC analysis was compensated by determining response factors; calibrations were performed for ten individual plant stanyl esters. For the analysis of low-fat products (skimmed milk drinking yogurts), the GC separation was combined with a "fast extraction" under acidic conditions. For fat-based foods (margarines), online coupled LC-GC offered an elegant and efficient way to avoid time-consuming sample preparation steps. The robust and rapid methods allow conclusions on both, the stanol profiles and the fatty acid moieties, and thus provide a basis for the authentication of this type of functional food ingredients.     

Spatial distribution and sample size to estimate Euschistus heros population density in wild plants during off-season

Journal of Plant Diseases and Protection - The neotropical brown stink bug Euschistus heros (F.) is an important pest for many crops in several countries and its ability to survive on associated...     

中国苜蓿审定登记品种叶形态特征及变异分析

利用CI-202型叶面积仪研究29个我国审定登记苜蓿品种(Medicago sativa L.)的叶长、叶宽、叶面积、叶周长、叶长/叶宽和叶形指数。结果表明:地方苜蓿品种和育成品种在叶形态方面存在着较大的差异,前者的叶片较后者小;二者叶片形状相似;在6个指标中,叶长宽比变异最大,叶周长变异最小;地方品种的叶面积、叶长、叶周长和叶长宽比的变异系数均高于育成品种,其他2项指标则低于后者;在育成品种中,中兰1号的变异最大,甘农3号苜蓿最小;在地方品种中,蔚县苜蓿的变异最大,河西苜蓿最小;该结果将为今后培育苜蓿新品种提供理论基础。     

Method for Precision Nitrogen Management in Spring Wheat: II. Implementation

By accounting for spatial variation in soil N levels, variable-rate fertilizer application may improve crop yield and quality, and N use efficiency within fields. The main purpose of this study was to demonstrate how site-specific wheat yield and protein data, and a geographic information system may be used in developing precision N-recommendations for spring wheat. The three steps in the procedure include: (1) estimate the amount of N-removed in wheat in the year in which the crop is harvested, (2) estimate the N-deficit, defined as the amount of additional N needed for raising protein concentration in a future crop to a specified target level, and (3) estimate the total N-recommendation by summing the mapped values of the N-removed and the N-deficit. A map for variable-rate application of fertilizer is derived by specifying cutoff values to divide the range in the total N-recommendation into classes representing N management zones.A field experiment was conducted within an annually cropped wheat field (101 ha) in northern Montana to determine whether the proposed method could improve grain yields and protein levels. The N-removal and N-deficit were estimated from site-specific wheat yield and protein data that were acquired during harvest of 1996. In 1997, which was a dry year, an experiment was conducted in the same field that consisted of a randomized complete block design arranged as pairs of strip plots. Variable- or uniform-rate N treatments were randomly assigned to each pair of strips. Both treatments received nearly the same amount of fertilizer, however, N in the variable treatment was varied to match patterns in grain yield and protein levels that previously existed in 1996. Yields were not significantly different between management systems, but proteins were significantly enhanced by spatially variable N application. In addition, variability in protein levels was reduced within the whole field. Field areas deficient in N fertility could be identified without having to sample for soil profile N.     

白足蚜小蜂对桃蚜的取食和寄生功能反应及搜寻效应

为评估白足蚜小蜂Aphelinus albipodus对桃蚜Myzus persicae的防控效果,在室内测定了白足蚜小蜂对不同发育阶段桃蚜的功能反应和搜寻效应,并对种内干扰和分摊竞争强度进行了比较。结果表明:白足蚜小蜂对不同发育阶段桃蚜的取食量和寄生量均随着蚜虫密度增加而增加,取食量和寄生功能反应均符合HollingⅡ模型。白足蚜小蜂对桃蚜的理论最大取食量2.809头,瞬时攻击率0.218,处理时间0.023 d;白足蚜小蜂对3～4日龄桃蚜寄生量最大,为47.62头,寄生瞬时攻击率0.723,处理时间0.021 d。搜寻效应均随蚜虫密度的增加而下降,且与蚜虫密度呈负相关。白足蚜小蜂个体之间存在种内干扰作用,随着自身密度增加,单头寄生率相对下降,分摊竞争强度增大,干扰效应符合Hassell-varley模型。由功能反应、种内干扰等指标可见白足蚜小蜂对桃蚜具有较好的防控作用。     

基于EDA技术的自动立木整枝机无线遥控发射系统

立木整枝是优质工业用材林定向抚育的重要环节,采用自动立木整枝机是实现高效、高质量和安全可靠整枝的有效途径。本文综合运用电子电路设计及优化技术、无线遥控及通信编解码技术,创造性地研制了基于CPLD的无线数字编码抗干扰自动立木整枝机无线遥控发射系统,通过优化CPLD内部逻辑电路有效消除了逻辑竞争冒险、降低了噪声干扰,确保了系统逻辑设计的正确性。该系统具有可靠、节能、抗干扰、工作效率高等优点。本研究成果及方法为推进其他林业机械的自动化与智能化进程提供了一种有效的新思路。     

猪仿生消化中小肠阶段消化酶对饲粮总能与粗蛋白质消化率的贡献

本试验旨在探讨猪仿生消化中小肠阶段主要消化酶的组成及活性对饲粮养分消化率的贡献,为仿生消化法评定猪饲粮养分的消化率提供参考。试验采用单因素完全随机设计,5个处理分别为胃模拟消化、胃+小肠(淀粉酶)模拟消化、胃+小肠(淀粉酶+糜蛋白酶)模拟消化、胃+小肠(淀粉酶+糜蛋白酶+胰蛋白酶)模拟消化、胃+小肠(淀粉酶+糜蛋白酶+胰蛋白酶+小肠消化4 h时补充消化酶)模拟消化,每个处理5个重复,每个重复1根消化管。考察各处理条件下玉米、豆粕、小麦麸及玉米-豆粕型饲粮的干物质、粗蛋白质及总能消化率的差异和各消化酶的贡献。结果表明:1)模拟小肠液中淀粉酶、糜蛋白酶均可显著提高胃消化后玉米、豆粕、小麦麸及玉米-豆粕型饲粮的干物质、粗蛋白质以及总能的消化率(P<0.05);胰蛋白酶可以进一步提高胃消化后豆粕、小麦麸的干物质、粗蛋白质以及总能消化率(P<0.05);补充3种消化酶可以提高对小麦麸粗蛋白质及玉米-豆粕型饲粮干物质、粗蛋白质及总能的消化率(P<0.05)。2)小肠液中消化酶对饲粮养分消化率的贡献上,因饲粮底物的不同而异,其中淀粉酶、糜蛋白酶对总能和粗蛋白质消化率的贡献相对较高,而胰蛋白酶和补充消化酶对饲粮养分消化率的贡献虽然相对较少,但也可以引起消化率显著性差异(P<0.05)。在猪的小肠模拟消化阶段,淀粉酶、糜蛋白酶、胰蛋白酶及补充消化酶对饲粮养分的消化程度均有显著性贡献。