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31.

Background

Metabolic profile was initially designed as a presymptomatic diagnostic aid based on statistical analyses of blood metabolites to provide an early warning of certain types of metabolic disorder. However, there is little metabolic profile data available about Korean Hanwoo cows. Therefore, this study aimed to determine the reference intervals of metabolic profile for Korean Hanwoo cows.

Methods

Healthy animals (2,205) were selected and divided into early (day 1 to 95), middle (day 96 to 190) and late (day 191 to 285) period according to their gestating period. Metabolic profile including total protein (TP), albumin (Alb), urea (UREA), glucose (Glu), total cholesterol (T-Cho), long-chain fatty acid (LCFA), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGT), creatinine (Crea), calcium (Ca), inorganic phosphorous (iP) and magnesium (Mg) were analyzed using a TBA-40FR automatic biochemical analyzer. The data of Korean Hanwoo cows were then compared to those of the Japanese Wagyu cows.

Results

Most of the data of the Korean Hanwoo cows were relatively higher than those of Japanese Wagyu cows, with the exception of Glu and GGT. This may indicate that the nutritional level of feed for the Korean Hanwoo cows was higher than that of the Japanese Wagyu cows because of the different feeding system. In particular, relatively higher levels of UREA and LCFA were observed in the Korean Hanwoo cows, and this may also contribute to the low reproduction efficiency.

Conclusions

These findings may provide some theoretical basis for understanding the reproductive and feeding situation of Korean Hanwoo cows.  相似文献   
32.
为深入了解油用亚麻主要品质和农艺性状的遗传变异,以253份油用亚麻种质为研究对象,在3个环境下(内蒙古呼和浩特市、集宁市和锡林郭勒盟太仆寺旗)对其全生育天数、株高、工艺长度、单株果数、每果粒数、单株粒重、千粒重和分枝数8个农艺性状及棕榈酸、硬脂酸、油酸、亚油酸、亚麻酸、粗脂肪含量6个品质性状进行鉴定。结果表明,8个农艺性状的变异系数为5.66%~42.65%;6个品质性状的变异系数为4.10%~30.14%。全生育天数在太仆寺旗表现最长,为112.51 d;千粒重和单株粒重在集宁地区表现最大,分别为5.94和0.55 g;果粒数和单株果数在呼和浩特地区表现最多,分别为5.65和16.90;粗脂肪和亚麻酸含量在太仆寺旗地区表现最大,分别为39.53%和53.45%;亚油酸和棕榈酸含量在集宁地区最大,分别为16.41%和5.09%;油酸和硬脂酸含量在呼和浩特地区表现最大,分别为24.03%和8.31%。聚类分析表明,253份油用亚麻种质被划分为4个类群,相同地理来源的油用亚麻种质被聚到1个类群,为油用亚麻种质资源的收集保存与繁殖提供了科学依据。  相似文献   
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34.
Two feeding trials were conducted with juvenile largemouth bass Micropterus salmoides to evaluate alternative plant and animal source proteins for their ability to replace fish meal in practical diets. The first trial was designed to identify the most promising candidates. The second trial was conducted to evaluate how much of the fish meal could be replaced by those candidates. In Study 1, feed‐trained largemouth bass (3.1 ± 0.7 g) were randomly stocked into 18114‐L glass aquaria at 25 fish per aquarium. Fish were fed one of six experimental diets, each containing approximately 38% crude protein and 10% crude lipid, to apparent satiation twice daily. The control diet (CTL) contained 30% fish meal and 34.5% soybean meal. Diets 2–6 each contained 15% fish meal and at least 34.5% soybean meal with the remainder of the protein made up of either meat and bone meal (MBM), soybean meal (SBM), poultry by‐product meal (PBM), a 50150 mixture of blood meal and corn gluten meal (BM/CG), or 50150 mixture of hydrolyzed feather meal and soybean meal (FMISBM). There were three replicate aquaria per dietary treatment. After 12 wk, there was no significant difference (P > 0.05) among treatments in survival which averaged 92% overall. Only fish fed the PBM or BM/CG diets had average individual weights and feed conversion efficiencies that were not significantly different (P > 0.05) from the control diet (CTL). In Study 2, the formulation of the control diet (CTL) remained the same. Based on their performance in the first trial, PBM and BM/CG were chosen to now replace 75 or 100% of the fish meal. Fish were stocked at an average weight of 6.9 ± 1.7 g. After 11 wk, fish fed diets containing the BM/CG mixture at both levels were significantly smaller (P 5 0.05) than fish fed other diets and at 100% replacement survival was reduced. Fish fed diets containing poultry meal as the primary protein source performed as well as those fed the control diet (CTL). It appears that PBM can completely replace fish meal in diets for juvenile largemouth bass without adverse effects on growth, feed efficiency, or body composition.  相似文献   
35.
36.
人工林UHF频段电波传播场强预测模型   总被引:1,自引:0,他引:1  
人工林无线电波传播场强模型是合理设计人工林环境无线电遥测遥控等通信电路的理论依据.该文在分析无线电波传播机理的基础上确定了人工林UHF频段传播损耗的三大组成部分及相应的计算方法,提出了人工林中某接收点处电场强度的预测模型.经过对北京西山人工侧柏林中不同参数的场强测试数据进行分析,校验了所建模型具有很高的精度.   相似文献   
37.
持续、低剂量金霉素对肉仔鸡免疫机能的抑制作用研究   总被引:14,自引:0,他引:14  
270只Abore Acre商品代肉用公鸡随机分成3组,金霉素在饲料中添加水平分别为0、50只和150mg/kg,研究饲用金霉素对肉仔鸡法氏囊、脾脏和胸腺等免疫器官发育、以及免疫反应的影响。结果表明50mg/kg的金霉素对肉仔鸡脾脏和21日龄的胸腺无明显抑制作用,对T、B淋巴细胞转化率也无明显抑制作用(P<0.05),而且显著促进法氏囊的萎缩(P<0.05)。金霉素对T淋巴细胞转化率有明显的直接抑制作用;50mg/kg和150mg/kg的金素对BAS特异性抗体的产生均有显著的抑制作用(P<0.01)。研究结果表明,持续、低剂量和金霉素对肉 鸡免疫器官发育和免疫应答具有显著的抑制作用,抑制作用随剂量增加而加强,150mg/kg的金霉素对肉仔鸡具有显著促生长作用。  相似文献   
38.
The quantum-confined Stark effect in single cadmium selenide (CdSe) nanocrystallite quantum dots was studied. The electric field dependence of the single-dot spectrum is characterized by a highly polarizable excited state ( approximately 10(5) cubic angstroms, compared to typical molecular values of order 10 to 100 cubic angstroms), in the presence of randomly oriented local electric fields that change over time. These local fields result in spontaneous spectral diffusion and contribute to ensemble inhomogeneous broadening. Stark shifts of the lowest excited state more than two orders of magnitude larger than the linewidth were observed, suggesting the potential use of these dots in electro-optic modulation devices.  相似文献   
39.
基于EDA技术的自动立木整枝机无线遥控接收系统   总被引:1,自引:0,他引:1  
在分析自动立木整枝机工作过程和控制要求的基础上,该文详细阐述了自动立木整枝机无线遥控接收系统的组成及工作原理,进而采用电子设计自动化(EDA)技术设计了自动立木整枝机无线遥控接收系统的数字控制逻辑.通过优化CPLD内部逻辑电路,有效消除了逻辑竞争冒险.仿真结果表明,该系统控制可靠性较高,能有效提高自动立木整枝机的功能安全性.   相似文献   
40.
针对牙齿组织形态学研究的难点,选择适宜固定液,用EDTA-2Na进行脱钙,完成了牙齿组织石蜡切片的制作。通过确定染色程序及各种染料的最佳作用时间,分别利用Masson三色染色法、传统的苏木精和伊红(HE)染色法对牙齿组织切片进行了染色观察。染色结果表明,与HE染色法相比,Masson三色染色更能使牙齿的各主要成分以不同颜色显现出来,色彩对比鲜明,亮丽润眼,为牙齿组织生理及病理组织形态学研究奠定了基础。针对机体中硬组织的相似特性,该试验方法可以在骨骼、软骨等硬组织的形态学研究中参考、改进并推广使用。  相似文献   
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