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41.
国内众多专家、学者仁者见仁,从饲料企业的各个角度谈到了饲料企业执行力方面的问题,并提出了许多有针对性的建议。本篇文章,笔者根据多年对饲料企业的研究,从执行力执行的过程方面.对饲料企业指令下达的各成员要素进行分析.并对指令执行流程中的各参与要素进行初步研究.在此分析研究的基础上,从管理学角度给出一些合理化的建议,希望给相关的饲料企业在经营管理上能够有所帮助。  相似文献   
42.
In order to assess the survival of lactic acid bacteria (LAB) in whole crop maize silage in the gut of dairy cows, one representative silage sample and three different feces samples were collected from dairy cows on three dairy farms in Hua Bei, China and three dairy farms in Kyushu, Japan. The composition of the bacterial community was examined by denaturing gradient gel electrophoresis and quantitative polymerase chain reaction. Lactobacillus acetotolerans was detected in all bunker‐made maize silage samples, regardless of the dairy farm or sampling region from which they were sourced. A total of eight LAB species were detected in the maize silage samples, of which three (L. acetotolerans, L. pontis and L. casei) appeared to survive digestion. The populations of L. acetotolerans in silage and feces were 106–7 and 103–4 copies/g, respectively, indicating that, even for the LAB species showing potential survival in the gut, competition in this niche may be harsh and the population may substantially decrease during the digestion process. It may be difficult for silage LAB to survive in the gut of silage‐fed dairy cows, because marked decrease in population can take place during the digestion process, even for surviving species.  相似文献   
43.
浅谈畜禽病毒病的治疗   总被引:1,自引:0,他引:1  
本文从临床兽医角度分析了病毒颗粒结构,病毒的侵入、致病过程,介绍了现在兽医临床上常用的几种抗病毒药物,并根据病毒病的特点,结合笔者临床经验着重介绍了病毒病在不同时期的预防和治疗方案。  相似文献   
44.
牦牛瘤胃内饲料蛋白质降解率的研究   总被引:3,自引:0,他引:3  
用瘤胃尼龙袋技术测定了11种常见饲料在牦牛瘤胃内的降解率。根据饲养水平,瘤胃食糜的外流速度估计为0.067/h。测定结果表明,玉米、豌豆秸粉、菜籽饼、豌豆、鱼粉、曲拉、肉骨粉、青稞、甲醛鱼粉、甲醛菜籽饼和麸皮的粗蛋白(CP)降解率分别为0.68、0.56、0.44、0.85、0.49、0.55、0.81、0,83、0.38、0,48和0.79,干物质(DM)降解率依次为0.68、0.30、0.49、0.73、0.50、0,54、0,59、0.82、0.32、0.49和0.74。  相似文献   
45.
运用建立的质量控制图,监控不同实验条件对布鲁氏菌试管凝集实验结果可能造成的影响。在每次日常检测时对标准阳性血清进行试管凝集实验并使用浊度仪测量其上清液的光密度(OD值),在收集足够有效数据后,绘制当前条件下的质量控制图。通过模拟日常实验条件下孵育温度、时间等容易产生偏离的条件,记录不同实验条件下标准阳性血清试管凝集实验后上清液的OD值,绘制控制用控制图。运用绘制的质量控制图对不同实验条件进行监控,发现孵育温度和孵育时间均对实验结果产生较大影响,从而导致失控。采用质量控制图对布鲁氏菌试管凝集实验进行监控,可提高质量监控的有效性、科学性。严格控制实验条件是保证实验结果的重要前提。  相似文献   
46.
This study was designed to investigate the effects of dietary lipid levels on growth performance, lipid deposition and activities of lipid metabolic enzymes in hybrid tilapia (Oreochromis niloticus × O. aureus). Four isonitrogenous (300 g/kg crude protein) experimental diets containing graded levels of lipid (25, 55, 85 and 115 g/kg) were randomly assigned to triplicate groups of 180 juvenile fish. Fish were fed twice daily for 8 weeks. At the end of the experiment, the growth performance and proximate composition of fish were determined. The activities and gene expression of lipoprotein lipase (LPL) and hormone-sensitive lipase (HSL) were assessed as well. Fish fed the diets with 55 and 85 g/kg lipid had a significantly (p < 0.05) higher body weight gain than those fed the diets with 25 and 115 g/kg lipid. The whole-body and liver lipid contents were significantly (p < 0.05) elevated with increasing dietary lipid levels. Moreover, the activities and mRNA abundances of LPL and HSL in the liver, dorsal muscle and fat tissues were markedly altered by dietary lipid levels. Our data demonstrate a profound influence of dietary lipid levels on the growth and lipid deposition in hybrid tilapia, which is likely associated with the regulation of lipid metabolic enzymes including LPL and HSL.  相似文献   
47.
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   
48.
Zhang Q  Li D  Liu X  Liu Z  Cai X  Wu G  Qi S  Yang S  Yan X  Shang Y  He J  Ma J  Li J  Ma W  Han R  Liu X  Zhang J  Xie Q  Zhang Z 《Research in veterinary science》2008,85(2):368-371
This study was carried out to investigate the biological characteristics of the foot-and-mouth disease (FMD) virus strain Asia-1 China/2005, which is responsible for the 2005 epidemic in China. The result showed that this strain is not host restricted, and could not only cause FMD in cattle and sheep but also in pigs by either inoculation or direct contact.  相似文献   
49.
圈养条件下北极熊的饲养繁殖   总被引:1,自引:0,他引:1  
毕延台  于淼  姚琳  韩晶晶 《野生动物》2010,31(3):121-123
对大连森林动物园圈养条件下北极熊的饲养管理、发情交配、繁殖及幼仔人工育幼等方面进行了研究与分析,为北极熊在动物园的饲养与繁殖,尤其在人工育幼方面取得了大量的基础数据,希望对北极熊的圈养繁殖起到一定的推动作用。  相似文献   
50.
We examined the effects of oral administration of L-citrulline (L-Cit) on plasma metabolic hormones and biochemical profile in broilers. Food intake, water intake, and body temperature were also analyzed. After dual oral administration (20 mmol/head/administration) of L-Cit, broilers were exposed to a high ambient temperature (HT; 30 ± 1°C) chamber for 120 min. Oral administration of L-Cit reduced (p < .001) rectal temperature in broilers. Food intake was increased (p < .05) by heat stress, but it was reduced (p < .05) by L-Cit. Plasma levels of 3,5,3′-triiodothyronine, which initially increased (p < .0001) due to heat stress, were reduced (p < .01) by oral administration of L-Cit. Plasma insulin levels were increased by heat exposure (p < .01) and oral L-Cit (p < .05). Heat stress caused a decline (p < .05) in plasma thyroxine. Plasma lactic acid (p < .05) and non-esterified fatty acids (p < .01) were increased in L-Cit-treated heat-exposed broilers. In conclusion, our results suggest that oral L-Cit can modulate plasma concentrations of major metabolic hormones and reduces food intake in broilers.  相似文献   
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