Brief communication: a cranial morphometric assessment of the taxonomic affinities of Trachypithecus auratus (E. Geoffroy, 1812 primates: Colobinae) with a reassessment of the T. auratus type specimen

The debate over the taxonomic position and affinities of Trachypithecus auratus has been ongoing since its identification by E. Geoffroy Saint-Hilaire in 1812. The type specimen of this species is housed in Muséum national d'Histoire naturelle in Paris (MNHN-ZM 2005-912). This point is debated due to the complex and fluctuating taxonomy of Southeast Asian Colobinae (Brandon-Jones et al.: Int J Primatol 25 (2004) 97-164) and to the fact that this individual is represented by a mounted skeleton. By means of 3D medical imaging methodologies we describe for the first time the cranial anatomy of the specimen MNHN-ZM 2005-912 and compare it with other Trachypithecus species, in order to test the molecular systematic hypotheses for affinities among the T. auratus-T. cristatus group. We ascertain the taxonomic attribution of this individual to the species Trachypithecus auratus species. The most diagnostic characters shared by the type specimen and Trachypithecus auratus compared to other species of Trachypithecus are the rounded orbits and the straight facial profile. We then try to clarify the inconsistencies concerning the geographical provenance of the type. The island of Java appears to be the most probable locality from a cluster analysis based on linear morphometry. After this approach and a discriminant analysis, a northeastern Javanese provenance of this specimen, as proposed by Brandon-Jones et al. (Int J Primatol 25 (2004) 97-164) is dubious. Finally we provide 3D models of the skull and the endocast, and a list of cranial landmark coordinates of the holotype for future research.     

Larval-rearing and growout of the red porgy (Pagrus pagrus) in the Riopesca hatchery (Greece)

Juveniles of red porgy (Pagrus pagrus 1758 L.) were experimentallyproduced in RIOPESCA hatchery during Spring 1992–95. Wild broodstock,weighing from 500 to 1000 g, was caught and brought to the hatchery insummer 1991. They were placed in a 30 m³ rectangular outdoorbroodstock tank with a sea-water flow of 5 m³ per hour.Salinity ranged from 3.9 to 4.1%, temperature from 13 to25°C , the stocking density was 4 kg m^–3,and the sex ratio was 1:1. The females spawned spontaneously in captivity producing approximately 200 000 eggs per kg of body weight. The percent offertilization was between 85–95%. Hatching was completed 85 hours later at 18 °C with a hatching percent of80–90%. The larvae were introduced into a 15 m³tank using green water (Nannochloropsis gaditana & Isochrysis galbana)and fed rotifers (Brachionus rotundiformis), Artemia salina nauplii andmetanauplii, and artificial food. After the end of the weaning period (day80 posthatch) the juveniles reached a weight of 1.4 g with a mean percentof survival of 10%. The fry were transferred to a cage site in which the growout proceeded without particular difficulties. The onlyproblem during growout was the skin coloration, that was darker than thatof wild porgies. Red porgies growth in our installations is satisfactory,with fry reaching 360 ± 12 g within 19 months, with a foodconversion rate of 1.8:1 , and a 6% mortality.     

天然三倍体鲫鱼突变体萍乡肉红鲫线粒体细胞色素b基因序列分析

用细胞色素b(Cyt b)基因特异性引物,对萍乡肉红鲫(Carassius auratus var.pingxiangnensis)的线粒体Cyl b基因进行PCR扩增和双向测序.在12个个体中均得到序列一致的Cyt b基因全序列,长度为1 140 bp.其A、T、G、C含量分别为28.2%(321)、28.8%(328)、14.8%(170)和28.2%(321),A+T含量(57%)明显高于G+C含量(43%).与其他水生动物相同基因片段碱基含量相似.该基因中密码子第1位核苷酸中4种碱基组成较为均衡;第2位核苷酸中T的使用率较高,为41.8%,G的使用率较低,为13.2%;密码子第3位A的使用率较高,为39.7%,而G的使用率较低,仅为6.3%.BLAST结果显示,萍乡肉红鲫与其他鲫鱼类的Cyt b基因具有较高的同源性,其中与银鲫(C.a.gibelio)的相似性为93%,与普通鲫鱼(C.carassius)的相似性为98%.邻接法构建的分子系统进化树表明,萍乡肉红鲫与普通鲫鱼亲缘关系最近.     

Behavioural and autonomic thermoregulation in hamsters during microwave-induced heat exposure

1. 1.|Preferred ambient temperature (T_a) and ventilatory frequency were measured in free-moving hamsters exposed to 2450 MHz microwaves. A waveguide exposure system which permits continuous monitoring of the absorbed heat load accrued from microwave exposure was imposed with a longitudinal temperature gradient which allowed hamsters to select their preferred T_a. Ventillatory frequency was monitored remotely by analysing the rhythmic shifts in unabsorbed microwave energy passing down the waveguide.

2. 2.|Without microwave exposure hamsters selected an average T_a of 30.2°C. This preferred T_a did not change until the rate of heat absorption (SAR) from microwave exposure exceeded approx. 2 W kg⁻¹. In a separate experiment, a SAR of 2.0 W kg⁻¹ at a T_a of 30°C was shown to promote an average 0.5°C increase in colonic temperature. Hamsters maintained their ventilatory frequency at baseline levels by selecting a cooler T_a during microwave exposure. In contrast, hamsters maintained at a T_a of 30°C (without a temperature gradient) underwent a sharp increase in ventilatory frequency compared to animals allowed to select their own T_a.

3. 3.|These data support previous studies suggesting that during thermal stress behavioural thermoregulation (i.e. preferred T_a) takes prescedence over autonomic thermoregulation (i.e. ventilatory frequency). It is apparent that selecting a cooler T_a is a more efficient and/or effective than autonomic thermoregulation for dissipating a heat load accrued from microwave exposure.

红鲫(♀)×湘江野鲤(■)杂交一代生殖腺的细胞学研究

研究了以红色鲫鱼作母本和湘江野鲤作父本所得杂交一代(F_1)生殖细胞的生长发育。实验证明:(1)F_1雌性个体的生殖腺存在两种情况,一是完全能育型,占总数的44.3%;另一是发育不正常的类型,属两性嵌合体,占总数的55.7%。外观为雌性个体的两性嵌合体卵巢,既有卵细胞,也有精细胞。(2)F_1雄性个体的生殖腺出现三种不同的状况,一是完全能育型,只占总数的4.67%,可以完成由精原细胞到精子形成的全部发育过程;二是不完全能育型,占总数的61.7%,有少数精子细胞可以通过变态形成精子;三是完全不育型,这种类型包括有两性嵌合体(20.63%)和非两性嵌合体(13%),都不能产生成熟的精子。根据我们的实验结果证实,鲫(♀)、鲤((?))杂交所得的杂交一代(F_1)雄性个体,有部分是能育的,并已成功地获得了第二代(F_2)和第三代(F_3)。     

银鲫(Carassius auratus gibelio)成熟精子染色质的结构和碱性蛋白的研究

银鲫属行雌核发育的遗传系统,其精子入卵后不能形成雄性原核。如同其它种类的精子一样,在精子发生过程中其染色质形成高度浓缩的具有一定结构的DNA和碱性蛋白的复合物。为了研究分析银鲫成熟精子的碱性蛋白、染色质的结构及其与体细胞染色质的异同,我们用聚丙烯酰胺凝胶电泳分析了银鲫精子碱性蛋白的组分,并结合核酸酶解的结果,以电镜铺片和超薄切片法探讨了银鲫染色质的结构。聚丙烯酰胺凝胶电泳分析表明,银鲫精子的碱??性蛋白为含H_1、H_2a、H_2b、H_3及H_4五个主要组分的组蛋白,且与体细胞核组蛋白无明显差异。电镜铺片法观察精子染色质,可见染色质丝的近100A粗细的串珠状结构。小球菌核酸酶水解精子染色质,DNA的琼脂糖电泳呈“阶梯型”电泳条带,证实了银鲫成熟精子保存了核小体基本单元,在低渗处理后的精子超薄切片中,可以见到直径为300A左右的染色质纤维,这个结果提示了精子染色质与体细胞染色体有类似的二级结构。根据以上所得到的结果推测,行雌核发育的银鲫,其精子在入卵后不能原核化,与精子染色质的基本结构及碱性蛋白组分无明显直接关系。     

金鱼酯酶同工酶的研究——Ⅰ.鲫鱼和红虎头金鱼各组织器官酯酶同工酶的比较

本文采用pH不连续系统聚丙烯酰胺垂直平板电泳方法,对鲫鱼和红虎头金鱼的眼、肝脏、肾脏、肌肉、卵巢(或精巢)、脑和心脏等7种新鲜组织的酯酶(EST)同工酶进行了比较研究。其结果是:鲫鱼(Carassius auratus)和红虎头金鱼(Carassius auratus var.)不仅具有丰富的EST同工酶和组织特异性,而且在它们的各个相应组织之间也显示出差异。表明酯酶同工酶在金鱼种内是有差异的。这对于探讨金鱼种内各品种之间的亲缘关系将是一个很有用的手段。     

我国现有的金鱼品种的分类及其系统发育的探讨1)

一、引言 金鱼是我国广大人民乐于饲养的一种家养观赏鱼类。它是由野生红黄色鲫鱼演变而来的。明朝李时珍在《本草纲目》中记载:金鱼“述异记载晋桓冲游庐山,见湖中有赤鳞鱼,即此也。”他还写道:“自宋始有畜者,今则处处家养玩矣。”因此可以认为金鱼起源于我国晋朝(公元265—420年间)。至今已有一千多年的历史了。 李璞(1959)报道了我国的金鱼品种已有二十余个。徐金声等(1980)报道有143个之多。耶么迄今为止我国的金鱼品种究竟有多少呢?为了弄清我国的金鱼品种资源,作者曾在北京等十七个省市的各大公园和花木公司所属鱼场作了调查。在调查过程中,我们     

洞庭湖外睾吸虫新种及其生活史

本文报告洞庭湖区鲶鱼肠道寄生的洞庭湖外睾吸虫Exorchis dongtinghuensis sp.nov(新种)及其全程生活史,其第一中间宿主为湖北钉螺Oncomelania hupensis;第二中间宿主为鲤鱼、鲫鱼和金鱼;终宿主为鲶鱼Parasilurus asotus。作者对各期宿主作了人工感染试验和现场自然感染调查。对其发育过程作了观察比较。