舍饲条件下猪只福利的实现与设施配套

舍饲饲养是目前养猪业中广泛采用的一种工艺模式，虽然它具有占地少、便于饲养管理、可实现一定程度的环境调控等优点，但由于舍饲条件下环境相对贫瘠，猪只的福利较难得到保障。该文重点讨论了国内外生猪舍饲条件下相关因素与猪只福利之间的关系，分析了舍饲环境下因福利问题而带来的一些不利影响。根据目前国内外现有的研究结果，指出我国应加强舍饲条件下的猪只福利问题研究的必要性，并就改善舍饲条件下猪只福利的措施及相关配套设备进行了论述，为我国养猪业持续健康的发展、增强我国养猪业的国际竞争力提供了一些思路。     

舍饲条件下猪只福利的实现与设施配套

舍饲饲养是目前养猪业中广泛采用的一种工艺模式,虽然它具有占地少、便于饲养管理、可实现一定程度的环境调控等优点,但由于舍饲条件下环境相对贫瘠,猪只的福利较难得到保障。该文重点讨论了国内外生猪舍饲条件下相关因素与猪只福利之间的关系,分析了舍饲环境下因福利问题而带来的一些不利影响。根据目前国内外现有的研究结果,指出我国应加强舍饲条件下的猪只福利问题研究的必要性,并就改善舍饲条件下猪只福利的措施及相关配套设备进行了论述,为我国养猪业持续健康的发展、增强我国养猪业的国际竞争力提供了一些思路。     

基于深度图像和生猪骨架端点分析的生猪步频特征提取

为高效提取生猪的行走快慢特征,以微软公司Kinect作为图像采集设备,采集生猪运动深度图像序列。在对各帧深度图像进行骨架提取、剪枝的基础上,采用基于路径相似性骨架图匹配法确定生猪前后肢骨架端点,进一步以骨架端点所属骨架枝子集像素值特征判定端点远近侧属性。以生猪前后肢远、近侧端点的帧间相对坐标变化建立了生猪运动模型,提出了通过帧间坐标变化点集拟合正弦曲线计算生猪行走完整步的方法。最后,通过计算序列完整步与序列采集时间长度比值提取生猪步频特征。通过对采集的28个生猪运动深度图像序列及其镜像序列共56个图像序列进行的试验,表明该文提出方法的正确率达到82.1%。该项研究对于开展生猪异常步态分析,进一步建立生猪多源特征融合的计算机视觉异常监测系统,提高生猪异常行为预警可靠性具有重要意义。     

Nitrate leaching and intensive outdoor pig production

Abstract. The production of pigs in outdoor units is gaining in popularity in the United Kingdom and is often concentrated on free-draining soils over important aquifers. Originally, stocking rates were sufficiently low to ensure the maintenance of a grass crop, but recently they have increased. Pigs are natural 'rooters' and wallowers and so cause damage to vegetation and soil structure. With overstocking these natural activities lead to considerable areas of bare, uncropped ground for much of the year. This paper assesses the potential for leaching of nitrate from such land, and makes recommendations for decreasing it.     

Dust in pig buildings

It is well documented in the international scientific literature that airborne dust in pig houses can cause serious health problems for humans as well as for animals. Extensive research has been carried out in different countries during the last few decades to improve the scientific understanding of air quality issues related to intensive animal production. Research and review papers were presented at the international symposium on Dust Control in Animal Production Facilities, held in Denmark in 1999. Different techniques have been used in order to reduce dust burdens in pig confinement buildings, but up to date only the procedure of spraying oil or a mixture of oil and water has contributed to reducing the indoor dust concentrations significantly. This article summarizes the current level of understanding of dust issues in intensive animal production buildings, mainly on the basis of papers presented at the above-mentioned symposium.     

Maturity indices for composted dairy and pig manures

Bulking agents and bedding materials used on farms for composting manures affect the time required for composts to mature. The effects of these materials on guidelines for the use of composted manures in potting mixes are not fully known. Several chemical and biological compost characteristics were mentioned and a cucumber plant growth greenhouse bioassay was performed on samples removed from windrows during composting of: (i) dairy manure amended with wheat straw; (ii) dairy manure amended with sawdust (mostly Quercus spp.); and (iii) pig manure amended with sawdust and shredded wood (mostly Quercus spp.). Dry weights of cucumber seedlings grown in fertilized and unfertilized potting mixes amended with composts (30%, v/v) having stability values of <1 mg CO₂-C g^-1 dw d⁻¹, did not differ significantly from those in a control peat mix. Only the most mature dairy manure-wheat straw compost samples consistently established sufficient N concentrations in cucumber shoots in unfertilized treatments. For the dairy manure-wheat straw compost, all possible subset regression analyses of compost characteristics versus cucumber plant dry weight revealed that any of several compost characteristics (electrical conductivity-EC, compost age, total N, organic C, C-to-N ratio, ash content, CO₂ respirometry, Solvita CO₂ index and the Solvita^® Compost Maturity Index) predicted growth of cucumber in the unfertilized treatments, and thus maturity. In contrast, at least two characteristics of the dairy manure-sawdust compost were required to predict growth of cucumber in the unfertilized treatments. Effective combinations were EC with compost age and the Solvita^® maturity index with total N. Even five compost characteristics did not satisfactorily predict growth of cucumber in the non-fertilized pig manure-wood compost. Nutrient analysis of cucumber shoots indicated N availability was the principal factor limiting growth in potting mixes amended with the dairy manure-sawdust compost, and even more so in the pig manure-wood compost even though the compost had been stabilized to a high degree (<1 mg CO₂-C g⁻¹ dw d⁻¹). Maturity of the composted manures, which implies a positive initial plant growth response of plants grown without fertilization, could not be predicted by compost characteristics alone unless the bulking agent or bedding type used for the production of the composts was also considered.     

基于生猪外形特征图像的瘦肉率估测方法

为实现生猪瘦肉率的快速无损检测,以机器视觉为主要技术,通过生猪的外形特征图像进行瘦肉率估测,为饲养者与收购者提供生猪品级的决策依据。采用MATLAB为开发工具,通过图形用户界面(graphical user interface,GUI)实现软件操作界面,以生猪的侧面及背面图像为研究对象,利用图像处理技术从目标中提取体长、体高、胸深、腹长、臀宽、腰宽等数据,以这些体尺的比例(胸深体高比、臀宽体长比、臀宽腰宽比、腹长体长比)为参数,通过径向基函数(radial basis function,RBF)神经网络进行瘦肉率估测。该文分别对7组生猪外形图像进行处理,4项比例指标的平均估测准确率分别为92.90%、92.44%、95.17%、96.51%,瘦肉率的平均估测准确率为94.35%。结果表明,该文所构造的基于生猪外形特征图像的瘦肉率估测方法工作效率高,成本低,可用于估测生猪瘦肉率。     

Forms and plant-availability of sulfur in cattle and pig slurry

The contribution of animal slurry to the supply of S to plants was studied. The total-S content of cattle and pig slurry was significantly correlated to DM and nitrogen content and was composed of sulfide, sulfate and C-bonded S. During 42 weeks of storage sulfate concentrations decreased and sulfide and C-bonded S concentrations increased. In a pot experiment plant-availability of S in slurry was found to be low, 5 to 7% of total-S.     

猪粪氮素有效性与替代化肥氮当量研究

采用温室盆栽试验,初步研究了猪粪氮素的有效性和替代氮肥的替代当量,并结合田间试验对等有效氮条件下有机无机配施与单施化肥的效果进行了比较。盆栽试验表明,随着猪粪用量的增加,氮素回收率逐渐降低,回收率为22.5%～38.3%,平均30.6%。当猪粪用量为N 120 mg/kg时,其氮素相对于化肥的相对有效性为27%。不同用量下猪粪的替代氮肥当量也具有一定差异,相对替代当量为24.0%～40.8%,平均32.9%。田间试验表明,利用猪粪中的有效氮替代30%的化肥氮对春玉米干物质和籽粒产量以及氮素吸收量没有影响,与100%化肥氮处理相当。     

猪Fas基因的克隆及序列分析

从PK-15细胞中提取总RNA,用RT-PCR方法扩增出猪F as基因,将其克隆到PM D 18-T载体上,进行序列分析。结果表明,克隆的猪F as基因序列与G enB ank上登录的猪F as基因同源性为100%,与人、牛、羊的F as基因核苷酸及推导的氨基酸序列同源性分别为73.4%、79.2%、76.4%和56.2%、67.0%、64.6%。F as蛋白胞内区的死亡域,其氨基酸序列在猪、人、牛和羊的F as基因中呈现较高的同源性。     

规模养猪场户清洁生产认知与行为的影响因素及其作用机理——基于山东省509家规模养猪场户的调查数据

生猪养殖是重要的环境污染源,规模养猪场户实施清洁生产行为是防治生猪养殖污染的重要途径。为从根本上降低生猪养殖污染,避免废弃物末端治理带来的弊端,实现环境效益与经济效益相统一。依据计划行为理论,利用山东省17地市509份问卷调查数据,运用结构方程模型,实证研究了规模养猪场户清洁生产认知与行为的影响因素及其作用机理。结果表明,由如何看待清洁生产和对生猪养殖污染熟悉度组成的规模养猪场户清洁生产态度,以及由年龄、受教育年限和生猪养殖出栏量组成的规模养猪场户禀赋特征对清洁生产认知具有显著的正向影响;由政府对清洁生产支持力度和经营组织对清洁生产的要求组成的外部规范对清洁生产认知有正向影响,但并不显著;规模养猪场户清洁生产认知对源头预防行为、过程控制行为和末端治理行为有显著的正向影响;规模养猪场户清洁生产态度、禀赋特征及外部规范约束对清洁生产行为有间接影响。其作用机理为：规模养猪场户清洁生产行为受制于认知程度,而认知程度又是行为主体态度、外部规范和主体自身禀赋特征共同作用的结果,而三者产生的作用条件又归因于外界环境（政府机构、经营组织、上下游企业等）与行为主体间的不断沟通。可见,规模养猪场户清洁生产行为作用机理并非单个因素间简单的线性作用,而是全产业链参与者与其所处环境间相互作用的结果。因此,应当根据认知与行为的影响因素和作用机理,提高规模养猪场户对清洁生产的积极态度,加强外部规范性,强化主体自身良好的禀赋,通过较高的认知水平正向作用于行为的形成和完善,并最终从根本上降低生猪养殖污染,实现经济效益与环境效益相统一。     

鸡、猪BPI氨基端的基因克隆和鉴定

为了克隆杀菌/通透性增加蛋白(BP I)N端cDNA,构建重组体pM D 18-T-BP I,并进行序列鉴定,应用RT-PCR技术,参照G enB ank报道的预测序列,从鸡多形核白细胞(PM N)mRNA中扩增出杀菌/通透性增加蛋白(BP I)氨基端95个氨基酸的基因片段,并与pM D 18-T连接,构建BP I氨基端的基因重组体,进行酶切鉴定和序列测定;从猪PM N的总mRNA中扩增出BP I氨基端48个氨基酸的基因片段,进行测序鉴定。获得鸡BP I N端长度为285 bp的基因片段。序列分析证实该片段中有3个点突变,但均不在活性中心;获得猪BP IN端长度为146 bp的基因片段。成功克隆出BP I N端基因,经序列测定,确认为BP I基因,为进一步表达该基因奠定了基础。     

中小型养猪场风机调速系统

为了适应中小型养猪场环境控制的需要,该文介绍了一种新型的单相风机调速控制系统。该系统使用单片机来控制单相交流通风机,通过改变风机的供给功率,达到调速、控制通风的目的,且结构简单,成本低廉,实际应用效率较高。     

稻秸与猪粪静态好氧共堆肥的最佳配比

为揭示稻秸与猪粪静态好氧共堆肥的最佳配比,采用室内培养法,以腐殖质组成为评价依据,对稻秸与猪粪按照7种质量比[10∶0(Rs),9∶1(Rp1),7∶3(Rp2),5∶5(Rp3),3∶7(Rp4),1∶9(Rp5)和0∶10(Pm)]混合后,于不同时间对物料进行水溶性物质、可提取腐植酸、胡敏酸、胡敏素碳含量(C_(WSS)、C_(HE)、C_(HA)、C_(Hu))以及胡敏酸碱溶液E_4/E_6、腐殖化系数(C_(HA)/C_(FA))的动态分析。结果表明:(1)与稻秸相比,猪粪中有更高含量的C_(WSS)和C_(HA),而C_(Hu)含量较低;(2)与0 d相比,90 d堆肥结束时,各处理C_(WSS)和C_(Hu)含量均有不同程度降低,其中,Rp1处理对CWSS的消耗程度最大,Rp3处理对C_(Hu)的分解作用最强;(3)在供试处理中,仅有Rp1处理在堆肥结束时能使C_(HE)增加13.1%,其余处理C_(HE)均表现为消耗;(4)Rp5处理在堆肥结束时能够促进HA分子的缩合,相反,其他处理HA分子的芳构化程度均有所下降。随堆肥进行,各处理HA均表现为先降解、再缩合的规律,稻秸占堆肥总质量≥30%,经堆肥后有利于腐殖质品质的提升,而猪粪占堆肥总质量≥90%,则堆肥后腐殖质品质会有所下降。     

生猪养殖格局变化中的环境风险与防范

养殖业是中国农业农村经济的支柱产业,也是最重要的农业污染源。在环保政策高压和产业政策引导下,中国南方传统养猪大省生猪出栏减量较大,北方逐步承接,形成“南猪北养”之势。“南猪北养”是中国农业整体北移的一个缩影,同时在饲料供给、资源环境禀赋等方面有其合理性。但同时也必须认识到,“南猪北养”格局形成的同时也存在着巨大的环境风险。本研究基于此,分析了现有生猪养殖布局调整可能会带来的潜在环境风险以及由此导致的环境不公正。一是北方地区的气候条件和耕作制度不利于养殖粪便的资源化;二是对北方水资源供给和水环境质量带来较大的潜在风险;三是养殖转移后有可能导致部分区域养殖密度过大,超出土地承载,对局部生态环境造成威胁。因此,为了避免以牺牲东北的冰天雪地为代价保护南方的绿水青山,应当建立和完善跨区域的生态补偿机制,降低南北资源环境的不公平程度;合理利用养殖区域空间,科学布局,避免局部养殖过密;落实和创设种养结合的约束和激励政策;严格落实对承接区养殖场的环保要求,并在此基础上创新污染减排方式。     

单只猪轮廓图的侧视图识别

由于完整轮廓猪只的侧视图具有便于行为分析的价值,因此,研究从猪舍监控视频中自动分割出单只猪理想侧视图的视频段对猪的行为分析是有意义的.为了识别每帧图像猪轮廓图的侧视图属性,该文通过图像处理获取猪只轮廓图后,提出联立猪只外接矩形高宽比和低频傅里叶系数构建猪只侧视图的特征向量,并根据样本训练集得到理想侧视图和非理想侧视图特征向量均值和方差,利用马氏距离判别法从测试视频中识别未知帧图像的类别,结果表明有91.7%猪只轮廓图的侧视图属性能正确识别,表明本方法是有效的.本研究可为后继单只疑似病猪行为分析提供条件.     

Nitrification in soils incubated with pig slurry

Incubation studies (5 weeks at 30°C) of nitrification were made in an acid (pH 5.8) and a neutral (pH 7.1) soil receiving varying concentrations of pig slurry and (NH₄)₂SO₄ solution. Mineral-N and pH changes were observed at weekly intervals and inorganic salts media were used to obtain separate estimates of the numbers of NH₄-N- and NO₂-N-oxidizing bacteria. In the acid soil, pig slurry NH₄-N was nitrified to a greater extent than (NH₄)₂SO₄. In the neutral soil, slurry additions resulted in the accumulation of NO₂^?-N and, in one case, the complete inhibition of nitrification for 4 weeks. Slurry raised the pH of both soils more than (NH₄)₂SO₄ and nitrification in the acid soil was most rapid in a 2 week period of elevated pH following slurry applications. Numbers of Nitroxomonas isolated from the acid soil were considered high enough to account for NH₄-N oxidation in slurry-treated samples. Numbers of nitrifiers recovered from the incubated neutral soil samples were variable but frequently high enough (>10⁴/g dry soil) to account for observed rates of nitrification. Results are discussed in relation to heterotrophic nitrification in soils, and the practical implications of spreading slurry on agricultural land.     

运输时间和温度对生猪应激和猪肉品质的影响

为了研究运输时间和温度对生猪应激及猪肉品质的影响,该文以三元杂交猪杜长大为研究对象,测定了运输前、运输3、6、9h以及运输温度-10~0℃、0~10℃、10~20℃、20~30℃等条件下生猪的血液生化指标、宰后猪肉p H值、肉色等指标。结果表明:运输6 h后三元猪出现应激反应,9 h以后应激反应显著增强(P0.05),运输6 h以上三元猪与运输3 h相比,宰后45 min p H值显著降低(P0.05),肉色分级显著升高(P0.05),肉品质降低;运输温度低于10℃时三元猪出现应激反应,-10~0℃时应激反应显著增强(P0.05),-10~0℃和20~30℃条件下宰后24 h p H值显著高于0~10℃和10~20℃(P0.05),肉品质降低。因此,为防止生猪运输应激及改善猪肉品质,生猪运输时间应小于6 h,运输温度为10~20℃。该研究结果对屠宰行业减少生猪应激提高猪肉品质提供参考。     

Nitrogen losses from outdoor pig farming systems

Abstract. Nitrogen losses via nitrate leaching, ammonia volatilization and nitrous oxide emissions were measured from contrasting outdoor pig farming systems in a two year field study. Four 1‐ha paddocks representing three outdoor pig management systems and an arable control were established on a sandy loam soil in Berkshire, UK. The pig management systems represented: (i) current commercial practice (CCP) ‐ 25 dry sows ha^?1 on arable stubble; (ii) ‘improved’ management practice (IMP) ‐ 18 dry sows ha^?1 on stubble undersown with grass, and (iii) ‘best’ management practice (BMP) 12 dry sows ha^?1 on established grass. Nitrogen (N) inputs in the feed were measured and N offtakes in the pig meat estimated to calculate a nitrogen balance for each system. In the first winter, mean nitrate‐N concentrations in drainage water from the CCP, IMP, BMP and arable paddocks were 28, 25, 8 and 10 mg NO₃ l^?1, respectively. On the BMP system, leaching losses were limited by the grass cover, but this was destroyed by the pigs before the start of the second drainage season. In the second winter, mean concentrations increased to 111, 106 and 105 mg NO₃‐N l^?1 from the CCP, IMP and BMP systems, respectively, compared to only 32 mg NO₃‐N l^?1 on the arable paddock. Ammonia (NH₃) volatilization measurements indicated that losses from outdoor dry sows were in the region of 11 g NH₃‐N sow^?1 day^?1. Urine patches were identified as the major source of nitrous oxide (N₂O) emissions, with N₂O‐N losses estimated at less than 1% of the total N excreted. The nitrogen balance calculations indicated that N inputs to all the outdoor pig systems greatly exceeded N offtakes plus N losses, with estimated N surpluses on the CCP, IMP and BMP systems after 2 years of stocking at 576, 398 and 264 kg N ha^?1, respectively, compared with 27 kg N ha^?1 on the arable control. These large N surpluses are likely to exacerbate nitrate leaching losses in following seasons and make a contribution to the N requirement of future crops.