牧草-鹅-鲜食葡萄循环生态种养模式的构建与实践

为了提高葡萄园资源利用率和综合效益,构建了牧草-鹅-鲜食葡萄循环生态种养体系。实践表明,在设施葡萄园推广套种牧草养鹅、鹅粪生产有机肥料、有机肥料种植葡萄和牧草等高效配套技术,取得了良好的经济效益、生态效益和社会效益。实施牧草-鹅-鲜食葡萄循环生态种养是江苏沿海地区发展现代农业的一种有效生产模式。     

临界氮浓度稀释模型在牧草种子生产中的应用前景

氮素是影响牧草种子产量的关键因素,氮素对于植株分蘖、干物质生产、花序形成、产量组分动态变化等均具有影响.文章主要从临界氮浓度稀释模型的概念、构建方法、研究现状、应用等方面进行了综述,提出临界氮浓度稀释模型在实际生产中应用时存在的问题,并对其在牧草种子生产中的应用前景进行了展望.     

《家禽生产学》培养学生实践能力教学模式的建立

从大学教育中注重学生实践能力培养的重要性入手,对作者在《家禽生产学》专业教学中总结出的专业课《家禽生产学》的教学模式进行探讨,旨在提出一种新的思路——如何在专业课教学中培养学生的实践操作能力,以切实提高课程的教学效果,使学生在毕业后走向工作岗位时,既具有扎实的理论知识,又具有和娴熟的实践技能。     

Muscle reorganisation through local injection of stem cells in the diaphragm of mdx mice

Background

The diaphragm is the major respiratory muscle affected by Duchenne muscular dystrophy (DMD) and is responsible for causing 80% of deaths. The use of mechanical forces that act on the body or intermittent pressure on the airways improves the quality of life of patients but does not prevent the progression of respiratory failure. Thus, diseases that require tissue repair, such as DMD, represent a group of pathologies that have great potential for cell therapy. The application of stem cells directly into the diaphragm instead of systemic application can reduce cell migration to other affected areas and increase the chances of muscle reorganisation. The mdx mouse is a suitable animal model for this research because its diaphragmatic phenotype is similar to human DMD. Therefore, the aim of this study was to assess the potential cell implantation in the diaphragm muscle after the xenotransplantation of stem cells.

Methods

A total of 9 mice, including 3 control BALB/Cmice, 3 5-month-old mdx mice without stem cell injections and 3 mdx mice injected with stem cells, were used. The animals injected with stem cells underwent laparoscopy so that stem cells from GFP-labelled rabbit olfactory epithelium could be locally injected into the diaphragm muscle. After 8 days, all animals were euthanised, and the diaphragm muscle was dissected and subjected to histological and immunohistochemical analyses.

Results

Both the fresh diaphragm tissue and immunohistochemical analyses showed immunopositive GFP labelling of some of the cells and immunonegativity of myoblast bundles. In the histological analysis, we observed a reduction in the inflammatory infiltrate as well as the presence of a few peripheral nuclei and myoblast bundles.

Conclusion

We were able to implant stem cells into the diaphragm via local injection, which promoted moderate muscle reorganisation. The presence of myoblast bundles cannot be attributed to stem cell incorporation because there was no immunopositive labelling in this structure. It is believed that the formation of the bundles may have been stimulated by cellular signalling mechanisms that have not yet been elucidated.     

PERT网络模型在家禽规模养殖项目管理中的运用

本文针对农业科技专家大院草科鸡规模养殖项目运行和管理中存在的问题,就优化农业科技项目管理与提高项目运行的效用和功能,提出采用PERT网络模型管理农业科技项目的思路,并对项目管理过程、方法及注意事项等问题提出了建议。本文指出,运用科学的管理方法制定合理的项目运行计划,是进行科技项目组织管理、科学地配置资源和促进科研项目顺利完成的重要途径。     

Breeding objectives of Brangus cattle in Brazil

Our goal was to define a breeding objective for Brangus beef cattle in Brazil. Bioeconomic models were produced and used to estimate economic values (EVs). The scenarios simulated were typical full-cycle beef production systems that are used in tropical and subtropical regions. The breeding objective contained pregnancy rate (PR), warm carcass weight (WCW), mature cow weight (MCW), number of nematode eggs per gram of faeces (EPG) and tick count (TICK). Two models were used in series to estimate the EV. A deterministic model was used to simulate effects of PR, WCW and MCW on profitability with a constant parasite load. Subsequently, stochastic models were used to estimate economic values for TICK and EPG as consequences of their environmental effects on weight gains, mortality and health costs. The EV of PR, WCW, MCW, EPG and TICK, was US$1.59, US$2.11, −US$0.24, −US$5.35 and −US$20.88, respectively. Results indicate positive emphasis should be placed on PR (12.49%) and WCW (65.07%) with negative emphasis on MCW (13.92%), EPG (2.77%) and TICK (5.75%). In comparison with the indexes usually used, these results suggest a reformulation in the selection indexes of the beef production system in tropical and subtropical regions in order to obtain greater profitability.     

基于NRC模型下不同玉米副产品代谢蛋白预测产量与分子功能团特征参数相关性分析

试验基于NRC-2001模型预测不同玉米副产品代谢蛋白产量,利用光谱技术分析不同玉米副产品的分子功能团特征及二者之间的相关性并建立回归方程。采用NRC-2001模型对奶牛饲料蛋白营养价值进行评价,利用傅立叶变换红外光谱（Fourier transform infrared,FTIR）技术收集光谱数据并分析。结果显示,利用NRC-2001模型预测不同玉米副产品代谢蛋白特征参数具有显著差异（P<0.05）。其中,小肠中真可吸收代谢蛋白总量在玉米蛋白粉中有最高值,其次是玉米胚芽饼、玉米胚芽、玉米皮及玉米籽粒。饲料产奶价值（FMV）存在相同趋势。在光谱结构分析中,饲料的分子功能团特征参数存在显著差异（P<0.05）,蛋白代谢预测产量与分子功能团特征参数之间存在相关性,建立的回归模型拟合度较好。其中,玉米籽粒中酰胺Ⅰ带与纤维性碳水化合物的面积比值（Amide Ⅰ_CELC）显著高于其他饲料原料（P<0.05）,玉米胚芽的酰胺Ⅰ带与结构性碳水化合物的面积比值（Amide Ⅰ_SCHO）和Amide Ⅰ_CELC比值均较低（P<0.05）,而玉米皮的蛋白质酰胺Ⅱ带与结构性碳水化合物（SCHO）和纤维性碳水化合物（CELC）之间的光谱面积比值均显著低于其他饲料比值（P<0.05）,玉米胚芽饼的蛋白质酰胺Ⅱ带与总碳水化合物之间峰面积比值（Amide Ⅱ_TNSCHO）显著高于其他饲料原料（P<0.05）。在不同玉米副产品饲料中,瘤胃合成微生物蛋白（MCP）和小肠真可吸收微生物蛋白（AMCP）含量与蛋白质酰胺Ⅰ带与非结构性碳水化合物之间的峰面积比值（Amide Ⅰ_TNSCHO）无显著相关性（P>0.05）,但与其他各光谱分子功能团特征参数存在显著负相关（P<0.05）。Amide Ⅰ_TCHO和Amide Ⅱ_SCHO可共同作为预测因子估测小肠真可吸收瘤胃非降解蛋白（ARUP）、代谢蛋白（MP）和FMV,其决定系数均为0.997。本试验结果表明,不同玉米副产品基于NRC-2001模型下代谢蛋白预测产量与分子功能团特征参数之间存在相关关系,可利用傅立叶变换红外光谱分析技术对饲料营养价值进行快速分析和估测。     

Phytomass estimation using eMODIS NDVI and ground data in arid rangelands of Morocco

The assessment of rangeland productivity in semi-extensively grazed arid rangelands is a prerequisite for livestock management in relation to sustainable use of pastoral resources. The objective of this study was to assess rangeland productivity based on normalised difference vegetation index (NDVI) images. Data on phytomass were measured on 61 field samples in arid rangelands of Morocco, covering various rangeland categories during autumn (November) and spring (April), i.e. when phytomass is at low and high levels, respectively, for two consecutive years (2008 and 2009). Dekadal EROS Moderate Resolution Imaging Spectroradiometer (eMODIS) NDVI data were linearly regressed to field measurements for these four periods. Results show that phytomass values were correlated with NDVI during spring, with R² and RMSE values of 0.82 and 0.3 t ha^?1, respectively. This study indicates there is a high potential for operational use of remotely sensed data to estimate rangeland phytomass of semi-extensively grazed rangelands.     

Development of a composite orthopaedic pain scale in horses

This study addresses development and validation of a composite multifactorial pain scale (CPS) in an experimental equine model of acute orthopaedic pain. Eighteen horses were allocated to control (sedation with/without epidural analgesia - mixture of morphine, ropivacaine, detomidine and ketamine) and experimental groups: amphotericin-B injection in the tarsocrural joint induced pain and analgesia was either i.v. phenylbutazone administered post-induction of synovitis, or pre-emptive epidural mixture, or a pre-emptive combination of the 2. Inter- and intra-observer reproducibility was good (0.8相似文献   

Genetic analyses of piglet survival and individual birth weight on first generation data of a selection experiment for piglet survival under outdoor conditions

Genetic parameters of piglet survival traits and birth weight were estimated on the first generation data of a selection experiment aimed at improving piglet survival using a multiple trait linear and threshold model. Data on 5293 piglets for survival at birth, at day one after birth and during the entire nursing period, as well as individual birth weight and litter size, were recorded in an outdoor production system. Genetic effects of piglet survival traits and birth weight were estimated based on threshold and Gaussian models, respectively, using a Bayesian approach. The statistical model included as fixed effects selection group, parity, gender, fostering, gestation length and month of farrowing and, alternatively, an adjustment for litter size. Direct genetic effects (i.e. the piglet's genetic potential) for piglet survival and birth weight were estimated separately, whereas maternal genetic and environmental effects could only be estimated for the given data structure in a combined litter effect. Posterior means of heritabilities for direct genetic effects of survival at birth, at first day after birth and the entire nursing period, as well as birth weight, were 0.08, 0.07, 0.08 and 0.20, respectively. Genetic correlations among survival traits were in the range of 0.29 to 0.40 and indicate that these traits were mainly attributable to different genetic effects. Genetic correlations between direct effects of survival traits and birth weight ranged between 0.18 and 0.23 and were reduced when weights of stillborn piglets were omitted in the analysis or the traits were adjusted for litter size. The magnitudes of direct genetic effects of survival traits are substantially higher than estimates in the literature, which may indicate that these traits have a higher genetic influence under outdoor conditions. The use of birth weight in the multiple trait estimation provided important information for the estimation of survival traits due to its favourable genetic correlations with survival, its high heritability and its high information content as a continuously measured trait.