奶牛胎儿的父亲对母亲产奶量的影响

用中国黑白花奶牛研究了胎儿的父亲及犊牛初生重对母亲当胎及下一个泌乳期产奶量的影响,结果指出胎儿的父亲对母亲当胎及下一个泌乳期90天和305天的产奶量,都有极显著的影响,各占产奶总变异量的9.4％,15.3％及3.77％(P<0.01)。犊牛初生重对母亲产奶量的影响也显著(P<0.05)。当根据公牛的产奶预期差(PDM)将胎儿的父亲分为两组后,发现差异显著(P<0.05),胎儿父亲的PDM高,胎儿母亲的产奶量也高,因此胎儿母亲产奶量不仅受胎儿重量的影响,也受父亲PDM的影响。     

河南省农业综合生产能力的评价研究

本文建立了农业综合生产能力的评价指标体系，讨论了两种评价方法，并通过计算机测评系统，对河南省农业综合生产能力进行了系统的测算和分析。     

RAPD技术对地方鸡种群体遗传结构的分析

利用ＲＡＰＤ技术对４个地方鸡种和１个引进鸡种的群体遗传结构进行分析，通过筛选的５个随机引物ＯＰＨ－０２、ＯＰＨ－０５、ＯＰＨ－１３、ＯＰＨ－１６、ＯＰＧ－０７对５个鸡种的池ＤＮＡ进行多态性研究，结果表明：５个引物共产生条带６１个，扩增产物片段的长度一般从１５０ｂｐ－４ｋｂ。     

Effect of ruminal dosing of mechanical stimulating brush on rumination time, ruminal passage rate and rumen fermentation status in Holstein steers fed a concentrate diet

This experiment was conducted to determine the effect of ruminal dosing of a mechanical stimulating brush on rumination time, ruminal passage rate and rumen fermentation status in steers fed a concentrate diet at maintenance level. Animals were dosed three Rumen Faibu (RF) per head through the rumen fistulae (RF treatment) and not dosed (control) in a change‐over design. The organic cell wall content of the concentrate diet was 12.7% of dry matter. Daily time spent on rumination was very short in both treatments with 24 min in RF treatment and 15 min in control. The turnover rate of ruminal fluid in RF treatment was higher than that in control. There were no differences in ruminal pH and total volatile fatty acid concentration between RF treatment and control. Acetic and butyric acid concentrations were not different between the treatments. Propionic acid concentration tended to be higher in the animals on RF treatment than in control animals. The RF dosing in Holstein steers fed a low fiber diet did not affect the rumination time, but increased rumen digesta passage rate and ruminal propionic acid production.     

枣品种枣股有效结果年龄与丰产性的关系

根据枣股的有效结果年龄,把调查的125份枣品种分为4个类型:1～3龄枝结果为主;2～9龄枝结果为主;1～9龄枝结果为主和2～6龄枝结果为主,它们分别形成各类品种产量的85%以上。“1～3”型品种早果性强,早丰性好.但成龄树立体结果能力极差;“2～9”型品种早果性差,但开始结果后产量上升快丰产稳产:“1～9”型品种多数为小果型品种,虽早果性强,但早丰性差,盛果期树立体结果能力强;“2～6”型品种早果性较差,并有不同程度的大小年现象。     

可控止回阀水力特性的测试研究

本文运用水流相似原理，对可控止回阀的流阻系数曲线和动水力矩，进行了系统的水力模型试验研究，为该阀的节能效益和技术开发的可行性，提供了必要的科学依据，其流阻系数值为０．１９，优于液控蝶阀。     

刺槐抗旱造林技术的研究

在不同类型区及不同立地条件下，研究了提高剌槐成活率和生长量的抗旱造林技术。结果表明，采用径流集存、吸水剂蘸根、覆膜覆草及幼林地少量施肥技术，均可显著提高剌槐造林成率与生长量，提高幅度为２．０％－８．９％和１４．５％－８７．５％。采用混草技术可增收可观的优质牧草，经济效益和生态效益显著。     

丰宁“中国沙棘”资源及种群表型结构的研究

本文用样地调查和统计分析的方法研究了丰宁“中国沙棘”主要经济性状的变异,探讨了性状相关和各主要性状的组配情况,分析了主要经济性状变异的频数分布及种群特征和优种分布范围。认为丰宁的“中国沙棘”是以主干型、桔黄扁圆果、褐色种子植株为主体的多态型种群系统,是品质较好的种质资源,是沙棘树种改良的珍贵材料。     

APPLICATION AND EFFECTS OF RARE-EARTH ON SEEDLINGS

In order to improve the quality of seedlings and economic benefits,rare--earth experiments were carried out on eleven seedling-age-types of four silvicultral treespecies.Some indexes such as the increment,biomass and chlorophyl content weredetermined.The results showed that rare-earth can improve the growth in height anddiameter,increase the bioprductivity and increase the mean benefit by887766.29 yuan/hm~2.It is an effective method to improve the quality of seedlings for the characters such as lowcost and easy grasping.And the method can be widely used in seedling.     

猴头菌新菌株宁猴6号的选育初报

采用多孢分离技术产生多个新组合 ,经驯化筛选获得猴头新菌株宁猴 6号 ,宁猴 6号为适合用针叶林木屑物料栽培的新菌株。生物学特性表明 :猴头菌宁猴 6号菌丝生长适温 2 5～ 2 8℃ ,子实体生长适温 15～2 0℃ ,菌丝生长期短 ,36～ 4 0d长满瓶底 ,栽培袋在常温下培养 4 3～ 5 0d菌丝满袋。室内栽培生物学效率达5 6 .0 0 % ,室外栽培生物学效率达 6 1.4 0 % ,子实体中型匀称近球型 ,柄短或无柄 ,刺长 0 .9～ 2 .2cm。宁猴 6号不仅适于阔叶木屑栽培 ,最突出的是适应针叶林木屑栽培