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1.
应用5-HT免疫组织化学染色法,对冬春两季的莱芜黑山羊松果体进行了观察比较,以探讨松果体与下丘脑垂体-性腺轴的关系。结果显示,莱芜黑山羊松果体内存在大量5-HT阳性的松果体细胞及5-HT纤维;冬季松果体阳性细胞面积及阳性面积比都明显大于春季(P〈0.01),平均光密度在冬、春季间无明显差异(P〉0.05)。表明莱芜黑山羊松果体的功能活动呈现季节性变化,与羊的繁殖活动关系密切。 相似文献
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韩占兵 《河南畜牧兽医(综合版)》2001,22(11):7-7,48
14只2岁非洲黑鸵鸟按公母比例1:2~3分成4个繁殖组合,对产蛋、受精、孵化情况进行观察分析。结果显示,每只母鸵鸟年平均产蛋量为55.2枚,最高约为73枚,最低为39枚。4个组合鸟群之间种蛋的受精率存在显著的差异P<0.01,I组的受精率最高,为59.6%;IV组的受精率最低,仅8.9%。各组的受精率、孵化率差异不显著P>0.05,平均受精蛋孵化率达到92.6%。本次受精率较低的原因为公鸟年龄小,没有完全达到性成熟。 相似文献
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对 2 2 4只云岭黑山羊及其杂交羊在夏季用CIDR孕酮栓 PMSG法进行同期发情处理 ,结果表明 :①总体发情率为64 73 % ,移植率为 47 3 2 % ,其中发情羊在撤栓后 48小时内 10 0 %发情 ,同期化程度高 ;②楚雄羊 (n =44只 )、师宗羊 (n =96只 )、文山羊 (n =71只 )和杂交羊 (n =9只 ) ,发情率分别为 :5 2 2 7%、65 63 %、66 2 0 %和 10 0 0 0 % ,以杂交羊的同期发情率和移植率高于楚雄山羊 (P <0 0 1)、师宗山羊和文山山羊 (P <0 0 5 ) ,但三个地方的云岭黑山羊的发情率和移植率均无显著差异 (P >0 0 5 ) ;③ 1~ 2 5岁受体羊的发情率比 3~ 5岁羊高 17 74个百分点 (P <0 0 5 ) ,移植率高 11 0 6个百分点(P >0 0 5 ) ;④ 2 0~ 2 9kg羊的发情率分别比 3 0~ 3 9kg和 40~ 5 1kg的羊群高 19 2 3个百分点 (P <0 0 5 )和 2 6 0 1个百分点(P <0 0 1) ;移植率分别高 13 0 7和 14 83个百分点 (P >0 0 5 ) ;⑤青年羊的掉栓率显著低于经产羊 (P <0 0 5 ) ,而掉栓羊群和持栓羊群的发情率和移植率分别比较 ,差异不显著 (P >0 0 5 ) ;⑥处理羊在第 16天撤栓和第 17天撤栓的同期发情率差异不显著 (P >0 0 5 )。 相似文献
4.
马铃薯黑色地膜覆盖高产栽培技术及示范基地效益评价 总被引:1,自引:0,他引:1
黑色地膜覆盖平均单产达42660kg/hm^2,产值达40950元/hm^2;比白色地膜覆盖增产6375kg/hm^2,增产17.6%。比露地增产15480kg/hm^2,增产57.0‰黑色地膜比白色地膜覆盖产值增加6120元/hm^2,比露地产值增加14860.5元/hm^2,较露地净增产值3235.5元/hm^2。黑色地膜增产的主要原因是土壤含水量比露地高0.078-3.080个百分点,在马铃薯淀粉积累的关键时期,土壤含水量比露地高3.080个百分点。 相似文献
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G. Caria D. Arrouays E. Dubromel C. Jolivet C. Ratié M. Bernoux B. G. Barthès D. Brunet C. Grinand 《Soil Use and Management》2011,27(3):333-339
We studied the black carbon (BC) content of ca. 405 samples from French topsoil and artificial soil and carbonate mixtures. Our protocol involved three main steps: (i) decarbonation by HCl, (ii) elimination of non‐pyrogenic organic carbon in a furnace at 375 °C, and (iii) quantification of residual carbon by CHN analysis. BC content increased for calcareous soils according to their carbonates content. Subsequent analyses confirmed the existence of a methodological artefact for BC determination only in calcareous soils. Decarbonation changes the thermal properties of organic matter, creating more recalcitrant carbon than in the initial sample. Higher CaCO3 and organic carbon content results in a more pronounced artefact. The reversal of the first two steps of the chemo‐thermal oxidation method (i.e. thermal oxidation before soil decarbonation) eliminates this artefact. Overall, our results suggest that BC content may have been overestimated in a large number of studies on calcareous soils. 相似文献
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Degradation rates of pyrogenic carbon (PyC) under natural environmental conditions are largely unknown. Here we present results from a field experiment monitoring the change in mass, C- and N concentrations of a variety of charcoal types in a Norwegian boreal forest over a period of 20 months. The charcoal types represent different feedstock tree species, production temperature regimes, and placements in the forest, i.e. above ground, in the humus layer or in contact with the mineral subsoil. The types of charcoal had different initial C concentrations mainly depending on their production temperature. Nevertheless, all types of charcoal at all placements in the forest showed an initial drop in their C concentrations, which subsequently rose back to reach near initial values in part of the charcoal types. In part of the charcoal types, N concentrations decreased throughout the experiment, exhibiting considerable variation among feedstock species, production temperature regime, and placements in the forest. C/N ratios rose especially in charcoal made from wood of Scots pine (Pinus sylvestris L.), and charcoal that had been stored in contact with the mineral subsoil showed the most rapid mass gain. Our results confirm the important influence of production temperature and feedstock type on the degradation of charcoal, but they also show that microbial activity and environmental conditions play significant roles in charcoal degradation and thus for the fate of pyrogenic carbon under natural conditions. 相似文献
10.
LI Qin CHEN Yu-cun ZHAO Feng-yong ZHANG Jia-min ZHANG Shu-hui ZHU Zi-yan 《中国畜牧兽医》2016,43(7):1850-1855
In this study,we aimed to determine whether bear had different blood group systems.Whole blood samples were collected from 40 Asiatic Black bears in Fujian province,China.Tube method was used to detect antibodies in plasma,and antibody isotype was determined with 2-mercaptoethanol.Plasma was further analyzed by mass spectrometry.The plasma from four bears had antibodies,possibly IgM isoform,which could agglutinate RBCs from 30 bears.Blood samples from 10 bears were tested by human blood typing reagents.The results showed that 4 bears had blood type like human type O,while 6 bears had like human type B.Plasma protein had extensive homology to serum albumin-like isoform 1 found in giant panda (Ailuropodamelanoleuca).We suggested that Asiatic Black bear might have at least one blood group system with two blood types.If the sick bear needs blood transfusion,a cross-matching test was necessary.Moreover,giant panda might receive blood from Asiatic Black bear in case of emergency. 相似文献