90年代我国肉类产量的灰色预测与分析

本文应用灰色系统理论对我国90年代肉类产量作出灰色预测,精确度达99%.在分析80年代肉类产量的基础上,提出某些设想,作为有关方面的参考.     

丝羽乌骨鸡新品系早期产蛋性能相关研究

在相同的饲养管理条件下,比较乌骨鸡6个品系之间的产蛋性能差异以及乌骨鸡早期产蛋性状之间的相互关系.结果表明①.丝羽乌骨鸡开产体重与开产日龄有显著的正相关(P＜0.01);②.2月产蛋和3月产蛋之间也成显著的正相关关系(P＜0.01);1月产蛋与开产体重和2月产蛋都相关显著(P＜0.05);③.品系对开产日龄和开产体重都有极显著的影响(P＜0.01),对3月产蛋有显著影响(P＜0.05);④品系间1月产蛋和2月产蛋的差异不显著(P＞0.05).     

试论畜牧科技企业的发展和思考

畜牧科技企业既要将知识转化为技术,又要将技术转化为产业;决定其胜负的竞争力是核心技术,评价的标准一是技术的技术性,再一是技术的市场性;有效经营管理要有正确的经营策略和合理利润;本文还对产量、成本、盈利之间的关系进行了探讨.     

Factors affecting egg production and layer bird mortality in private poultry farms in the subhumid zone of Nigeria

Egg production and layer bird mortality data obtained from five different private farms in Zaria within the subhumid zone of Nigeria, over a 6‐year period (1994–1999) were subjected to least squares analysis to determine the effects of age, season and year. It was demonstrated that age had a highly significant influence (P < 0.01) on egg production in that birds falling within the age group 30–39 weeks produced the highest number of eggs (3255 ± 109), while birds over 100 weeks of age produced the lowest number of eggs (1206 ± 412). Similarly, seasonal variation in egg production was also significant (P < 0.05); the highest egg production (2926 ± 90) was obtained during the early dry season, and the lowest (2423 ± 95) during the late wet season. Mortality was generally low (0.0–0.9%) and not significantly different from 20 to 49 weeks of age (P > 0.05). However, from 50 to 100 weeks of age, highly significant differences (P < 0.01) in mortality were observed, with the 90–100 weeks age group recording the highest mortality of 15.7 ± 1.3%. Furthermore, yearly variations in egg production and mortality were highly significant (P < 0.01) with 1999 producing the most eggs (4410 ± 102) and recording the lowest mortality (1.4%). It was concluded that due to the significant seasonal, age and yearly variations, data on egg production and mortality need to be adjusted for these effects to enable unbiased comparison between and within farms. Furthermore, farmers can make adequate feeding preparations commensurate with each season for optimal egg production.     

增效剂对球孢白僵菌产孢量及对光肩星天牛致死速率的影响

在应用昆虫病原菌防治光肩星天牛（Ａｎｏｐｌｏｐｈｏｒａ ｇｌａｂｒｉｐｅｎｎｉｓＭｏｔｓｃｈ）的试验中，筛选出一种增效剂，可使病原菌的产孢量增加，光肩星天牛的致死速率加快。在生产病原菌的培养基内加入０．０２％的增效剂培养５天，产孢量比对照增加一倍多。在含孢量１０＾８／ｍｌ的球孢白僵菌的菌悬液中加入０．０２％的增效剂，以每头光肩星天牛幼虫接种１ｍｌ菌悬液，使光肩星天牛幼虫第６天开始发病，第１６天死亡     

影响鲜食子莲产量的形态指标相关分析和通径分析

对影响"南四湖"鲜食子莲产量的形态指标进行了相关和通径分析.结果表明,影响鲜食子莲莲子产量的主要形态指标与产量的相关程度依次为;莲蓬重(0.953 6)、莲蓬径(0.810 3)、莲子径(0.761 4)、莲子重(0.713 1)、果皮重(0.677 8)、成熟度(0.638 3)、莲子高(0.565 1)、莲子数(0.411 2),对产量的直接影响重要性依次为:瘪种子数(-0.456 4)、莲子重(0.450 1)、莲蓬重(0.434 2)、莲子数(0.266 5)、莲蓬径(-0.093 7)、莲子径(0.076 5)、成熟度(0.041 4)等;形态指标间具有明显的制约关系;并提出了增加子莲产量的策略和技术.     

燃煤固硫的热力学研究

从化学热力学的角度，分析了燃煤掺烧固硫时的吸放热情况和反应的SO2平衡体积分数规律，表明固硫反应的放热量较石灰石分解吸热量高，并且其热力学推动力很大。实验证实，往燃煤中掺入适当量的固硫剂，不仅对混合物的发热量无不良影响，而且一定条件下还可提高混合物的总发热量。     

单色光对蛋鸡产蛋性能的影响

本试验分别采用红(660 nm)、绿(560 nm)、蓝(480 nm)3种发光二级管(处理组)和白炽灯(400~770 nm)(对照组),对180羽海兰褐蛋鸡进行人工照明,每组45羽,光强度均为15 lx,光照时间为16 h,试验期为19~52周龄。结果表明:19~36周龄,蓝光组产蛋率(86.8±0.5)%显著高于其它光照组(P<0.05),其日产蛋量最高(47.7±0.34)g,料蛋比(2.75±0.07)最低,后两者与红光和绿光组比较差异显著(P<0.05)。37~52周龄,红光组产蛋率显著高于蓝光和绿光组(P<0.05),白光组日产蛋量(59.0±0.74)g显著高于其它组(P<0.05),其料蛋比(2.1±0.04)最低。19~36周龄,各组破蛋率之间差异不显著(P>0.05),但白光组软蛋率(1.3±0.3)%显著低于其它组(P<0.05)。在37~52周龄,各组破蛋率和软蛋率之间差异不显著(P>0.05)。结果表明:在15 lx光强度下,试验前期(19~36周龄)选用蓝光照明,后期(37~52周龄)改为白炽灯,可以显著提高产蛋量和饲料转换率。     

复合酶制剂对蛋鸡产蛋性能的影响

选择34周龄健康商品代罗曼蛋鸡1 920只,随机分成试验组和对照组,每组960只,两组基础日粮相同,试验组添加1 g/kg复合酶,对照组不添加,进行为期4周的试验.结果表明,在饲料中添加1 g/kg的复合酶制剂,能显著提高蛋鸡的产蛋率、饲料利用率和经济效益.