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91.
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93.
氯化钾对热应激肉仔鸡生产性能的影响 总被引:4,自引:0,他引:4
本试验测定了氯化钾对热应激肉仔鸡生产性能的影响。试验应用2l0只星布罗肉仔鸡,随机分成7组,每组30只。氯化钾按0%、 0.06%、0.12%、0.18%、0.24%、0.30%和0.36%添加到饮水中,试验温度为32±1℃,试验期为35天。结果表明饮水中添加0.24%、一0.30%氯化钾能显著提高热应激条件下肉仔鸡的生产性能。 相似文献
94.
闫忠心 《青海畜牧兽医杂志》2014,(1):1-3
为探索不同地区苦荞在高寒地区的农艺性状及生产性能,采用多重比较及聚类分析法分析了7个地区13种苦荞的农艺性状及生产性能。结果表明不同地区苦荞的农艺性状及生产性能差异显著(P0.05),云苦荞2号和晋苦荞2号的农艺性状及生产性能优于其他品种;聚类分析将13个荞麦样品分成2组,在一定程度上体现了荞麦资源的道地性特征,反映了不同苦荞品种的农艺性状及生产性能与亲缘关系之间有一定的联系。 相似文献
95.
Hun-Su Seo Kyoung Hee Kim Dae-Yong Kim Bong-Kyun Park Nam-Shik Shin Jae-Hoon Kim Heejeong Youn 《Journal of veterinary science (Suw?n-si, Korea)》2013,14(3):241-248
We analyzed alcoholic extracts of herbs possessing anti-neosporal activity against Neospora (N.) caninum. To identify the chemical components of Sophora (S.) flavescens and Torilis (T.) japonica associated with anti-neosporal activity, specific fractions were isolated by high-performance liquid chromatography (HPLC). In vitro activity of the fractions against N. caninum was then assessed. Gas chromatography/mass spectrometry (GC/MS) was used to identify and quantify specific anti-neosporal molecules in the herbal extracts. Almost all HPLC fractions of S. flavescens and T. japonica had higher levels of anti-neosporal activity compared to the not treated control. Active constituents of the extracts were sophoridane, furosardonin A, and tetraisopropylidene-cyclobutane in S. flavescens; 5,17-β-dihydroxy-de-A-estra-5,7,9,14-tetraene, furanodiene, and 9,12-octadecadienoic acid (Z,Z)-(CAS,1) in T. japonica. 相似文献
96.
以甘肃天祝地区3个牧场所产的白牦牛乳为研究对象,采用气相色谱-质谱联用检测方法,测定3个牧场所产白牦牛乳中脂肪酸含量,比较在枯草期、枯草末期、返青期、青草期4个时期及不同胎次的白牦牛所产牦牛乳中脂肪酸的构成及含量.结果表明:3个牧场白牦牛乳中乳脂肪酸含量差异不显著(P>0.05);1~5胎次母白牦牛乳中脂肪酸含量差异不显著(P>0.05).枯草期、枯草末期、返青期、青草期4个时期白牦牛乳中饱和脂肪酸(SFA)、不饱和脂肪酸(USFA)含量比值分别为1.86、1.75、1.62、1.32.随着气温的升高及牧草的成熟,白牦牛乳中饱和脂肪酸含量逐渐降低,而不饱和脂肪酸的含量逐渐升高. 相似文献
97.
Increases in labour productivity are essential factors, as well as technical effectiveness, for the competitiveness of pig farming. However, the preferences of farmers for controlled (i.e. limited) daily working hours or available days for vacation also increase. The objective of this study was to explore how these preferences about work might be associated to specific combinations of practices or affect performance. The study was carried out by direct investigation of the stockbreeders. Data analysis used factorial analysis to identify relationships between practices, labour productivity, sow productivity and work load distribution. Results showed independence between sow productivity and labour productivity. Three independent types of preferences about work load distribution were identified: the limitation of density of daily work, the avoidance of insemination activities during the weekend and the avoidance of farrowing supervision during the weekend. These preferences about work load distribution were mainly related to weaning, oestrus detection and insemination techniques. A relationship was also seen between farrowing and cross-fostering techniques, and labour and sow productivity. Results suggest that preferences about work load distribution influence the choice of reproduction practices without influencing performance. Finally, concerning the labour productivity, it was linked with some specific techniques at farrowing but the results also indicated that it was mainly related to the size of farrowing batches. 相似文献
98.
GUO Rong CUI Can LI Si-chen ZHU Qing LIU Yi-ping WANG Yan YIN Hua-dong YE Lin ZHANG Lu YUAN Yun-cong WANG Zhen ZHAO Xiao-ling 《中国畜牧兽医》2017,44(10):2994-3000
The purpose of this study was to provide the reference to Jiangxi Green-eggshell breeding through the analysis of laying performance, hatchability and egg quality in the first generation of Jiangxi Green-eggshell layers at 300-days old. 306 Jiangxi Green-eggshell layers and 80 eggs were selected to determine the laying performance, hatchability and egg quality among families, and the correlation between the hatchability and egg quality were analyzed also. The results were as fellows:The average body weight of these hens was 1 596.99 g, the average egg weight was 50.57 g, the average egg-laying number was 14.53, the average fertility rate was 93.69%, the average dead fertile egg rate was 5.55%, the average healthy chick rate was 84.3%, the average dead embryo egg rate was 13.9%, the average egg shape index was 1.28, the average Haugh unit was 71.77, and the average eggshell strength was 4.44 kg/cm2. The healthy chick rate and the egg weight had significant correlation,as well as the eggshell color and the egg shape index (P < 0.05). The healthy chick rate had extremely significantly correlation with the dead fertile egg rate(P < 0.01), as well as the eggshell strength and the eggshell thickness (P < 0.01). Generally, the first generation of Jiangxi Green-eggshell layers had good egg quality, higher laying performance and hatchability, but they still need to be further selected. 相似文献
99.
本研究旨在探讨饲粮能量水平对德州驴生长性能、营养物质消化率及血清生化指标的影响。试验选用健康的7~8月龄德州公驴36头,体重(123.9±5.0) kg,随机分为3个组,每组3个重复,每个重复4头驴。各组饲粮消化能水平分别为10.43 (低能组)、11.03 (中能组)和11.90 MJ/kg(高能组),粗蛋白质水平相近。预试期20 d,正试期40 d。结果表明:1)中能组和高能组的平均日增重显著高于低能组(P<0.05),且高能组的平均日增重显著高于中能组(P<0.05)。中能组和高能组的料重比显著低于低能组(P<0.05),且高能组的料重比显著低于中能组(P<0.05)。2)中能组和高能组的干物质、有机物和碳水化合物消化率显著高于低能组(P<0.05),且高能组的干物质、有机物和碳水化合物消化率显著高于中能组(P<0.05)。3)高能组的血清总蛋白、甘油三酯含量显著高于中能组和低能组(P<0.05)。中能组和高能组的血清白蛋白含量显著高于低能组(P<0.05),且高能组的血清白蛋白含量显著高于中能组(P<0.05)。中能组和高能... 相似文献
100.
宋慧卿 《青海畜牧兽医杂志》2006,36(5):16-17
采用高效液相色谱法对4.5%氯氰菊酯乳油中高效cisB及transB的含量进行测定,该方法测定结果稳定,线性良好,重复性较高。 相似文献