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Various dog breeds are remarkably different from each other not only in their sizes and shapes but also in behavioral traits, suggesting that some of these characteristics are under genetic control. However, little is known about genes related to behavioral traits in canine species. In humans, it has been reported that the dopamine receptor D4 gene (DRD4) includes polymorphism at several regions that relate to personality or psychiatric disorders. In an earlier study by the authors of the present study, the polymorphisms in canine DRD4 exon III and exon I regions were reported. In the present study, a novel polymorphism in canine DRD4 intron II was found based on a 17 base pair insertion/deletion, and the two alleles detected were named P (shorter allele) and Q (longer allele). The allelic distribution in 28 breeds of dog, including a total of 1114 unrelated individuals, were then investigated. Both P and Q alleles were detected in most of the breeds investigated; however, the frequencies of P and Q differed greatly between breeds. With respect to classification based on breed origin, P and Q alleles were frequent in Occidental and Oriental breeds, respectively. Furthermore, two subspecies of wolves, the ancestors of dogs, were analyzed for the comparison of allele frequencies with dogs, and the P allele was predominant in both European and Chinese wolves.  相似文献   
154.
A case of cervical deformity of lambs following dosage with vitamin D was investigated. The lesions of a scoliosis are described together with the kidney lesions. It is suggested that doses of vitamin D normally considered to be non-toxic to sheep may prove to be so under certain conditions.  相似文献   
155.
An 11-year-old, eight-months pregnant mare suddenly developed severe respiratory distress. Endoscopic examination identified intralaryngeal granulation tissue obstructing the airway. In order to avoid general anaesthesia and the problems associated with a permanent tracheostomy, the mass was resected electrosurgically while the mare was standing. Patency was restored to the airway and the mare foaled without complication.  相似文献   
156.
运用层次分析法和模糊数学综合评判方法,根据石河子、昌吉、吐鲁番等8个地区的无霜期、温度、积温和降水因素,建立了数学模型,并对新疆天然甜型葡萄酒原料种植区域进行了区划研究.结果表明:吐鲁番的综合评价最高,其次为和田,评价值分别为0.97和0.91,属非常适宜种植区;哈密和喀什的评价值分别为0.81和0.87,属适宜种植区;库尔勒的为0.71,属次适宜种植区,而石河子、昌吉和霍城的评价值均小于0.59,属不适宜种植区.  相似文献   
157.
采用自由基聚合法,以过硫酸钾为引发剂,磷酸酯淀粉与丙烯酸钠和丙烯酸钾进行接枝共聚,合成了含磷、钾的高吸水树脂;磷酸酯淀粉与低中和度的丙烯酸接枝共聚合成的高吸水树脂用氨水浸泡,自然凉干得到含氮、磷、钾的高吸水树脂,详细考察了丙烯酸的中和度对吸水保水剂吸液性能的影响。通过实验得到了合成该吸水保水剂的适宜条件。  相似文献   
158.
青贮饲料的特性   总被引:2,自引:0,他引:2  
青贮可以通过适宜的发酵,使作物的营养成分损失最小,并能满足家畜冬春季节及全年对饲料及营养物质的需求.青贮饲料与调制干草相比具有很多独特优势,对其独特的发酵特性进行了简单的分析和概述.  相似文献   
159.
160.
A liquid chromatographic method has been developed for the determination of free fatty acids in butter. The fatty acids are converted to the p-bromophenacyl esters, via a crown ether-catalyzed reaction, without separation from the other butter components. The esters are separated on a C18-bonded silica column by using an acetonitrile-water solvent gradient and quantitated using the ester of heptadecanoic acid as internal standard. C16 and C18:1 co-elute in the acetonitrile-water system but are separated using an isocratic methanol-acetonitrile-water system. Limits of detection range from 7 ng for butyric acid to 45 ng for linoleic acid. The average coefficient of variation (n = 10) for 10 free fatty acids from a butter was 5.83%.  相似文献   
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