Domesticating olfaction: Dog breeds,including scent hounds,have reduced cribriform plate morphology relative to wolves

The domestic dog is assumed by nearly everyone to be the consummate smeller. Within the species Canis familiaris individual breeds, such as the bloodhound or beagle, are known as olfactory stars. These are “scent breeds,” a grouping variably defined as a genetic clade or breed class commonly used for scent detection tasks. Previous work suggests that the dog has a more robust olfactory anatomy than many mammal species. Now we undertake a closer investigation of the dog's olfactory system, both in relationship to its closest wild relatives, the wolf and coyote, and across individual breeds. First, we seek to resolve whether the dog has lost olfactory capacity through its domestication from the wolf lineage. Second, we test the inertial lore that among dogs, “scent breeds,” have a superior olfactory facility. As a measure of relative olfactory capacity, we look to the cribriform plate (CP), a bony cup in the posterior nasal cavity perforated by passageways for all olfactory nerve bundles streaming from the periphery to the brain. Using high-resolution computed tomography (CT) scans and digital quantification, we compare relative CP size in 46 dog breeds, the coyote and gray wolf. Results show the dog has a reduced CP surface area relative to the wolf and coyote. Moreover, we found no significant differences between CP size of “scent” and “non-scent” breeds. Our study suggests that the dog lost olfactory capacity as a result of domestication and this loss was not recovered in particular breed groupings through directed artificial selection for increased olfactory facility.     

塑料暖棚养殖新技术在克州的应用与推广

塑料暖棚饲养牲畜的意义在于为畜禽在禽在寒冷季节生活和生产提供适宜的温热环境，为发展“两高一优”牧业提供了前提条件，开辟了一条加快畜牧业发展的崭新途径。它具有保温好、降低饲养成本、降低成幼畜死亡率等优点，在生产中以其投资小、周转快、效益高、易推广等优势，深受广大农牧民欢迎。     

川贝母性状及混淆品与伪品鉴别

川贝母其来源按药材性状分别习称松贝、青贝和炉贝。市场常见混淆品及伪品有珠贝、湖北贝母、光慈菇、土贝母、平贝母、伊犁贝母、天山贝母。     

Influence of feeding system (concentrate and total mixed ration) on fatty acid profiles of beef from three lean cattle breeds

The objective of this study was to examine the effect of two feeding systems (traditional concentrate plus cereal straw vs. total mixed ration) on the fatty acid composition of beef in lean beef breeds slaughtered at commercial weight. Two improved breeds, purebred Charolais (n = 60) and Limousine (n = 60), and one unimproved indigenous breed, Retinta (n = 60), were raised on either an indoor concentrate system or a unifeed system consisting of a mixture of maize silage and concentrate. Young bulls fed the total mixed ration system showed a higher percentage of saturated fatty acid content than young bulls fed with concentrate plus wheat straw. The intramuscular fat of Retinta bulls raised on a concentrate feeding system showed higher monounsaturated (587.3 mg/100 g edible meat) and lower polyunsaturated fatty acid (221.0 mg/100 g edible meat) than Retinta bulls that were fed with mixed ration. No feeding system effect on fatty acid profile of fat was observed for the improved breeds. At commercial weight, the percentage of fatty acid desirable for human health was higher (70.3%) from the unimproved breed than the improved breeds (69.1%). The results obtained confirm that genetic background plays an important role in the fatty acid profile of meat from cattle raised with different feeding systems.     

药用植物黄芪品种道地产区产量的AMMI模型分析

目的:筛选适宜在甘肃定西市多样性生态条件下种植的优良黄芪新品种。方法:采用AMMI模型分析基因型与环境互作效应方面的优势,对2012—2013年定西市4个主产县区选用7个参试品系进行丰产性及稳产性分析。结果:所有参试品系中HQZX04-03-02表现最稳定,但产量最低;HQZX04-04-01的稳产性较好,产量最高,较当地主栽品种陇芪1号增产24.23%;各试点间的鉴别力具有差异,其顺序为:漳县马泉渭源新寨岷县禾驮陇西首阳。结论:黄芪各品系不同试点AMMI模型中的主成分分值共解释总互作和的87.6%,比线性回归模型和方差分析能更有效地分析基因与环境的互作效应。     

家牦牛与野牦牛混群放牧杂交育种初步试验

本试验选择健康达标的家养母牦牛,经过适应性培育后,在发情季节与野牦牛混群放牧,采用自然交配手段导血培育半野血牦牛探索,成功获得了39头半野血牦牛(23公,16母),为今后在混群放牧条件下获得半野血牦牛积累了经验。     

A 60:40 split: Differential mass support in dogs

Dogs have been bred for different sizes and functions, which can affect their locomotor biomechanics. As quadrupeds, dogs must distribute their mass between fore and hind legs when standing. The mass distribution in dogs was studied to determine if the proportion of supported mass on each limb couplet is dependent on body size. A total of 552 dogs from 123 breeds ranging in size from Chihuahua to Mastiff were examined. Each dog was weighed on a digital scale while standing, alternating foreleg, and hind leg support. The overall “grand” mean proportion of mass on the forelegs to the total mass was 60.4% (range: 47.6–74.4%). The data set indicated no significant change in the ratio with total mass but there was a significant difference by sex. When separated into American Kennel Club categories, no group was notably different from the grand mean or from each other, but when sex was also considered, there was a significant difference that was not specifically discerned by post hoc analysis. The mean for female Hounds was notably below the grand mean. For clades based on genetics, the mean for European origin mastiffs was notably greater than the grand mean and significantly different from UK origin herders and coursers. The mass of the head, chest, and musculature for propulsion could explain the mass support differential. Mass distribution and terrestrial locomotion in dogs shows substantial variation among breeds.     

EST-SSR标记对三七选育品系的研究

目的:通过对不同三七选育品系的遗传变异和遗传分化程度进行分析比较,为三七的品种选育提供理论依据.方法:利用自行设计和他人开发的17对EST-SSR引物,对来自4个不同区域的17份三七选育品系进行遗传多样性及遗传分化分析.结果:在17份三七选育品系中一共扩增出136个多态位点,平均多态信息量PIC值为0.78,Nei's基因多样性H0.139,Shannon多样性指数I0.208.选育品系间的遗传分化系数为0.382,遗传相似度和聚类分析的结果表明17份三七选育品系和屏边三七被划分为4个大类群,其中17份三七选育品系被分为3个类群,屏边三七单独在一个类群.结论:通过集团选择后,从相同栽培居群内筛选出的不同品系存在一定程度的遗传分化,可以用EST-SSR标记来检测集团选择的结果.     

钩藤属植物部分品种药材钩藤碱成分的分析

目的:探索钩藤属部分品种钩藤碱成分的含量,为评价这些品种药材质量提供试验依据.方法:应用HPLC测定钩藤属攀茎钩藤、侯钩藤、毛钩藤、倒挂金钩、北越钩藤和华钩藤33批不同产地药材钩藤碱含量.采用Gemini C18色谱柱(4.6 mm×250 mm,5μm),流动相为甲醇-水(含0.002 mol·L 1三乙胺,用冰乙酸调pH7.5)(64∶36),流速为1.0 mL·min-1,检测波长254 nm.结果:攀茎钩藤和侯钩藤有5批样品可检出钩藤碱,但含量均较低,其余样品均未能检出钩藤碱.结论:试验所用钩藤属不同品种质量有所差异,同一品种质量随着产地不同而异.