肉种鸡鸡舍夏季通风降温试验

在两栋长145m，跨度5.4m的双坡式有窗封闭舍内，采用三层笼养方式分别饲养700只235日龄的艾维菌肉种鸡，将其中采用轴流式风机加湿帘纵向通风系统的一栋鸡舍作为试验组，而将另一栋采用窗户自然通风的鸡舍作为对照组，于夏季进行为期15d的试验，结果表明试验组与对照组的舍内温度在1d内明显不同，且舍外温度越高，试验组的舍内降温效果越好，相应地，试验组也减轻了肉种鸡的夏季热应激。     

Dot-ELISA检测猪胴体中沙门氏菌的研究

应用Dot-ELISA法对西宁某猪屠宰点 85份猪胴体进行了沙门氏菌的检测 ,同时采用常规分离培养鉴定技术作对照实验。结果在 85份肉样中 ,Dot-ELISA检出沙门氏菌阳性 6 5份 ,阳性率为 76 .4 7% (6 5 /85 ) ;而常规分离培养鉴定技术检出沙门氏菌阳性 6 7份 ,阳性率为 78.82 % (6 7/85 ) ,此两种方法的阳性符合率为 86 .5 7%。经统计分析 ,两种方法差异不显著 (P >0 .0 5 )。     

Research and Application of Decision - making System in Mine Fire

主要介绍了矿井火灾决策系统的组成及应用。矿井火灾决策系统能大大节省灾变时期的反应时间,为企业在第一时间采取果断措施尽可能消除或减少火灾损失争取宝贵的时间,对于矿井火灾的防治具有重要的意义。     

Seasonal changes in nutritional status and reproductive performance of Zebu cows kept under a traditional agro-pastoral system in Tanzania

The objectives of this study were to assess changes in nutritional status/body condition score, percentage pregnancy and calving rate in Zebu cows and to establish the relationship between body condition score loss and postpartum interval to resumption of ovarian activity. A total of 198 cows and postpubertal heifers of the Tanzanian Shorthorn Zebu kept under a traditional management system were randomly selected from 200 smallholder herds. Factors investigated during bi-weekly visits include body condition score (BCS), heart-girth circumference, milk yield and reproductive status of the animals, pregnancy/non-pregnancy and cyclicity/non-cyclicity. Local weather conditions and dates of occurrence of other reproductive events such as calving were also recorded. Calvings occurred all year round but with a strong seasonal distribution characterized by annual peaks observed between April and July. The annual calving pattern was closely related to rainfall, with peak precipitation occurring a few months before peak calving. The overall percentage pregnancy varied from 30% to 50% throughout the year. Postpartum cows exhibited minimum mean BCS and heart-girth circumference 12–14 weeks after calving, and cows with BCS loss >1 point exhibited the longest time interval from calving to onset of ovarian activity.     

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.     

朝鲜鹌鹑遗传多样性微卫星标记分析

选用鹌鹑上的12个微卫星位点,对随机选取朝鲜鹌鹑的40个个体进行多态性检测,共检测到55个等位基因,每个座位平均等位基因数为4.583个。该群体平均多态信息含量和平均杂合度分别为0.6945和0.7111,表明朝鲜鹌鹑属多态性较丰富的群体。     

中国南方草地现状与生产潜力

中国南方草地区为秦岭、淮河以南、青藏高原以东的广大地区 ,总面积约 2 70万 km2 ,分属淮河、长江、珠江 3大流域。南方草地多山 ,本文涉及的 12个南方省区中 ,山地与平原之比平均为 4 .85∶ 1,比全国平均比值高出 1倍。山地面积之大小与青藏高原距离的远近呈负相关。南方草地大体可以分为云贵高原区、华东区和华南区。笔者提出建立 3类系统耦合经济带 ,即西南岩溶山地系统耦合生态经济带、江淮平原丘陵系统耦合生态经济带和岭南沿海平原丘陵生态经济带。每一生态经济带内包含中心城市 ,农村生产基地和社会支持系统。据初步估算 ,这样的生态经济带蕴藏了巨大的经济潜力     

论国有企业改革中的土地资产处置

国有企业改革中的土地资产处置，关系到企业改革的成败。文章论述了国有企业改革中土地资产处置的必要性、处置方式、存在问题，本着“明晰产权、显化资产、依法处置”的原则，要“因地制宜、因企制宜”，即要有利于企业改革的顺利进行，又要避免国有土地资产的再流失。     

禽蛋中农药残留检测方法研究进展

禽蛋是人类获取动物蛋白的重要来源之一,禽蛋中残留的农药导致食品安全隐患,威胁人类健康,因此迫切需要建立有效的检测方法,为禽蛋产品的质量安全提供技术保障.文章综述了近十年来国内外文献报道及我国国家标准中规定的禽蛋样品农药残留的前处理方法和分析检测方法,为进一步研究建立简便高效的分析检测新方法、新技术提供参考.     

猪肉切块分割图示

文章对猪肉切块分割的方法做了图解,并评述了各部位切块对于肉质育种和商业品牌形象的参考意义。