淡水豚类分子系统发生的研究

测定了白暨豚和恒河豚细胞色素ｂ基因３０７ｂｐ的ＤＮＡ序列,并与其它鲸类的相应序列合并,分析了淡水豚类（恒河豚、印河豚、白暨豚、亚河豚和弗西豚）的系统学位置和系统发生。淡水豚类不同属间的序列差异已达到或超过了其它齿鲸类科间的差异水平,因此它们分别归属于不同的科,即恒河豚科、白暨豚科、亚河豚科和弗西豚科。系统发生分析支持淡水豚类和海豚类之间具有下述的关系：（恒河豚科（（白暨豚科（亚河豚科,弗西豚科））海豚总科））。即淡水豚的４个科中,恒河豚科是最早分化的一支,其次是白暨豚科,然后是亚河豚科和弗西豚科的分化。白暨豚科和亚河豚科＋弗西豚科组成海豚总科的姊妹群,并与海豚总科一同组成海豚下目。恒河豚与其它淡水豚类间无直接的亲缘关系。淡水豚类是并系的。把恒河豚类独立为恒河豚总科是合理的。初步认为有理由把白暨豚类也作为一个总科级的支系。恒河豚和印河豚间的序列差异极小,两者可能只是同一个种的２个亚种。     

淡水豚类线粒体DNA 12S rRNA基因的序列变异及其分子系统学研究

淡水豚类４个代表属「白暨豚（Ｌｉｐｏｔｅｓ）、恒河豚（Ｐｌａｔａｎｉｓｔａ）、弗西豚（Ｐｏｎｔｏｐｏｒｉａ）和亚河豚（Ｉｎｉａ）」ｍｔＤＮＡ １２Ｓ ｒＲＮＡ基因的序列差异水平,高于其他齿鲸类科间的差异,特别是远远高于海豚总科内的科间差异。研究结果支持它们应归属于不同的科,即白暨豚科（Ｌｉｐｏｔｉｉｄａｅ）、恒河豚科（Ｐｌａｔａｎｉｓｔｉｄａｅ）、弗西豚科（Ｐｏｎｔｏｐｏｒｉｄａｅ）和亚河豚科（Ｉ     

白既豚的骨骼和分类位置

1918年Miller比较了白既豚Lipotes vexillifer与亚河豚Inia geoffrensis的头骨与颈椎,认为白既豚是亚河豚的近亲,归属亚河豚科Iniidae。1960年,Fraser和Purves比较与鲸类听觉器官有关的骨骼及气窦(air sinus),把白既豚列入亚河豚亚科Iniinae。1972年,Brownell和Herald在关于白既豚的综述中报告其椎骨数两例,同时发表了头骨、牙齿及鼓围耳骨(tympaao-periotic)等照片。1973年,Kasuya根据鼓围耳骨的研究仍认为白既豚属于亚河豚科。1975年,陈宜瑜和陈炜报告其骨骼的某些特征,Bree和Purves报道对国外仅有三个头骨的测量。此六文中,对其骨髂的记述尚有疏误;对其分类归属都墨守Miller的观点,仅分类阶元有科或亚科之别。此外,在分类位置问题上,周开亚(1958)、寿振黄     

白暨豚的舌

在现代生存的四类淡水豚中,恒河豚(Platanista gangetica)和拉河豚(Pontoporia blain-villei)的舌已有详文报道(Arvy和Pilleri,1970;Yamasaki等,1976a)。亚河豚(Iniageoffrend)的舌也在Yamasaki的文章中作为和上述二种淡水豚舌的比较而述及。白暨豚(Liptes vexillifer)的舌除陈宜瑜等(1975)曾提及外,迄今未有其他报道。鉴此,作者对白暨豚的舌作了解剖学和组织学的观察,现将研究结果报告如下: 白暨豚舌的标本取自幼体、亚成体、成体和老年个体等七头个体。为了比较,还收集了亚河豚、其它海豚类和陆生哺乳类的舌。用10％甲醛固定保存,各项量度根据固定标本测量。白暨豚舌的外形描述以NNC 7909号标本为主,以其它个体的观察为辅。其组     

近年来我国关于白鱀豚Lipotes vexillifer的研究

白鱀豚是我国特有的珍贵水生哺乳动物,也是世界现存的4种淡水豚(拉河豚Pontoporia blainvillei,亚河豚Inia geoffrensis,恒河豚Platanista gangetica和白鱀豚)中存活头数最少的一种。近几年来,白鱀豚已为很多人所熟知,并像大熊猫一样,被视为我国的“国宝”。 对白鱀豚进行系统的研究工作,开始在中华人民共和国成立之后。特别是七十年代以来,我国的科学工作者对其进行了大量的调查研究。     

白鱀豚的胃

关于鲸类胃的复杂分室早有许多详细研究。现代生存的四类淡水豚中,恒河豚Platanista gangetica及拉河豚Pontoporia blainvillei的胃在十九世纪就作过观察(Anderson,1878;Burmeister,1867),近年有详文论述(Yamasaki等,1971,1974),但对白暨豚Lipotes vexillifer及亚河豚Inia geollrensis的胃尚缺了解。白暨豚的胃仅两篇报道(Hinton和Pycraft,1922;陈宜瑜和陈炜.1975)曾提到几句,但未正确阐明其构造。鉴于白暨豚的形态研究对淡水豚类的系统发生及分类均具一定意义,现报道其食管后部和胃的解剖及组织学观察结果。     

白鱀豚的肾脏

研究了4头雄性和9头雌性白鱀豚肾脏的结构和各项指标。白鱀豚肾脏是由许多小肾组成。肾脏和小肾的各项指标随着个体体长的增加而增加。与其他3种淡水豚相比,白鱀豚成体肾脏的小肾数比恒河豚多,比哑河豚少,而与拉河豚相近。白鱀豚幼体的肾脏和小肾的各项指标与恒河豚和亚河豚相近,但成体肾脏和小肾的各项指标比上述2种淡水豚大得多。并证实鲸类动物肾脏的小肾并生群在幼体即已存在,随着个体的长大,小肾化加剧,而并不是次级融合的结果。白鱀豚小肾的髓旁肌肉带的排列并无规律,它并不构成白豚鱀所特有的排列结构。       

雄性大熊猫对化学信息行为反应的年龄差异

化学通讯对哺乳动物的生存和繁殖起着重要作用。研究了雄性大熊猫(Ailuropoda melanoleuca)对同伴个体尿液气味行为反应的发育模式。结果显示,在成年雌性个体的尿液气味刺激下,雄性个体表现显著多的嗅闻行为和嗅闻/舔舐环境行为,但是嘶咬气味刺激物的行为明显减少。在雌性个体的尿液气味刺激下,不同年龄段的雄性个体行为表现不同,成年雄性个体表现较亚成年和幼年个体显著多的舔舐行为。此外,成年个体和亚成年个体均表现较多的嗅闻/舔舐环境行为,而幼年个体则无该行为表现。幼年个体较成年和亚成年个体表现显著多的气味涂抹行为,而且嘶咬气味刺激物的时间较亚成年个体显著多。幼年个体和亚成年个体对雌性和雄性个体尿液气味刺激的行为反应不存在显著差异。研究结果表明,雄性大熊猫对同种个体尿液中化学信息的行为反应呈现出年龄差异。     

河豚及其文化

通过识别河豚历史悠久、古籍中的河豚、现今的河豚及河豚的保护4个方面,介绍河豚鱼的历史文化。     

中国东方鲀属鱼类分类研究

东方鲀属(Fugu Abe,1952)鱼类属于硬骨鱼纲、鲀形目。在我国沿海分布甚广,产量大。因体形似“豚”,常在河口捕到,故江、浙一带叫“河豚”。北方俗名叫廷巴,南方叫龟鱼。河鲀肉味鲜美,含蛋白质甚高,久为广大人民所喜好,有些种类列为出口品种,畅销国外。但河鲀系有毒鱼类,早在李时珍名著《本草纲目》中即载有:“河豚有大毒,味虽珍美,修治失法,食之杀人”。故食河鲀时必须将含有剧毒的肝脏、生殖腺和血液等剖洗干净后,     

"PUSHY" BEHAVIOR IN A WILD DOLPHIN FEEDING PROGRAM AT TANGALOOMA, AUSTRALIA

A program where wild bottlenose dolphins (Tursiops truncatus) are fed by tourists in shallow water adjacent to a wharf has been established at Tangalooma, Queensland, Australia. Up to nine dolphins attend the nightly feedings, and between 60 and 80 resort guests are permitted to hand feed these dolphins each night. Since this program began in 1992, the dolphins have increased in confidence and have started, at times, to make forceful contact with guests who enter the water to feed them. This paper categorizes such behavior as "pushy" and reports on a study which quantifies the "pushiness" of the dolphins which feed at Tangalooma. The study examines ecological variables which may determine how pushy the dolphins are at different feeding sessions. The number of dolphins attending a particular feeding significantly increases the pushiness. In addition, the presence of adult males at a feeding is likely to increase pushing. Tidal state also influences how pushy the dolphins are. At low tide, when the dolphins'mobility is restricted by the water depth, they are less likely to be pushy. Given the problems experienced in a number of other situations where wild animals are fed by humans, it is important to monitor carefully the escalation of pushy behavior in this dolphin feeding program, as it may be a precursor to more aggressive actions on the part of the dolphins.     

Precocial development of axial locomotor muscle in bottlenose dolphins (Tursiops truncatus)

At birth, the locomotor muscles of precocial, terrestrial mammals are similar to those of adults in both mass, as a percent of total body mass, and fiber-type composition. It is hypothesized that bottlenose dolphins (Tursiops truncatus), marine mammals that swim from the instant of birth, will also exhibit precocial development of locomotor muscles. Body mass data from neonatal and adult dolphins are used to calculate Grand's (1992) Neural and Muscular Indices of Development. Using these indices, the bottlenose dolphin is a Condition "3.5" neonate, where Condition 4 is the documented extreme of precocial development in terrestrial mammals. Moreover, myosin ATPase (alkaline preincubation) analyses of the epaxial locomotor m. extensor caudae lateralis show that neonatal dolphins have fiber-type profiles very similar to those of adults. Thus, based on mass and myosin ATPase activity, muscle development in dolphins is precocial. However, succinic dehydrogenase and Nile red histochemistry demonstrate that neonatal dolphin muscle has mitochondrial and lipid distributions different from those found in adults. These data suggest that neonates have a lower aerobic capacity than adults. Dolphin neonates may compensate for an apparent lack of aerobic stamina in two ways: 1) by being positively buoyant, with a relatively increased investment of their total body mass in blubber, and 2) by "free-riding" off their mothers. This study investigates quantitatively the development of a dolphin locomotor muscle and offers suggestions about adaptations required for a completely aquatic existence.     

A report from America: Baby M

Rachels reviews the social and legal facts of the celebrated "Baby M" case, in which surrogate Mary Beth Whitehead attempted to keep the daughter she had borne under contract to William Stern. The first phase of the legal battle between the parents ended in March 1988, when New Jersey Superior Court Judge Harvey R. Sorkow upheld the validity of the surrogacy contract, terminated Whitehead's parental rights, and awarded custody of the child to Stern. Rachels comments on public reaction to "Baby M," on Sorkow's decision, and on the impact the case may have on legislative attempts to regulate surrogacy. He also uses the example of "Baby M," as well as that of California heart transplant patient "Baby Jesse," to discuss how the media sensationalize controversial issues.     

Isolation and characterization of a Helicobacter sp. from the gastric mucosa of dolphins, Lagenorhynchus acutus and Delphinus delphis

Gastric ulcerations in dolphins have been reported for decades. Some of these lesions were associated with parasitic infections. However, cases of nonparasitic gastric ulcers with no clearly defined etiology also have been reported in wild and captive dolphins. Considerable speculation exists as to whether dolphins have Helicobacter-associated gastritis and peptic ulcer disease. The stomachs of seven stranded Atlantic white-sided dolphins, Lagenorhynchus acutus, and 1 common dolphin, Delphinus delphis, were assessed for the presence of Helicobacter species. Novel Helicobacter species were identified by culture in the gastric mucosa of two of the eight dolphins studied and by PCR in seven of the eight dolphins. The gram-negative organisms were urease, catalase, and oxidase positive. Spiral to fusiform bacteria were detected in gastric mucosa by Warthin Starry staining. Histopathology revealed mild to moderate diffuse lymphoplasmacytic gastritis within the superficial mucosa of the main stomach. The pyloric stomach was less inflamed, and bacteria did not extend deep into the glands. The lesions parallel those observed in Helicobacter pylori-infected humans. Bacteria from two dolphins classified by 16S rRNA analysis clustered with gastric helicobacters and represent a novel Helicobacter sp. most closely related to H. pylori. These findings suggest that a novel Helicobacter sp. may play a role in the etiopathogenesis of gastritis and gastric ulcers in dolphins. To our knowledge this represents the first isolation and characterization of a novel Helicobacter sp. from a marine mammal and emphasizes the wide host distribution and pathogenic potential of this increasingly important genus.     

Visual lateralization in wild striped dolphins (Stenella coeruleoalba) in response to stimuli with different degrees of familiarity

Background

Apart from findings on both functional and motor asymmetries in captive aquatic mammals, only few studies have focused on lateralized behaviour of these species in the wild.

Methodology/Principal Findings

In this study we focused on lateralized visual behaviour by presenting wild striped dolphins with objects of different degrees of familiarity (fish, ball, toy). Surveys were conducted in the Gulf of Taranto, the northern Ionian Sea portion delimited by the Italian regions of Calabria, Basilicata and Apulia. After sighting striped dolphins from a research vessel, different stimuli were presented in a random order by a telescopic bar connected to the prow of the boat. The preferential use of the right/left monocular viewing during inspection of the stimuli was analysed.

Conclusion

Results clearly showed a monocular viewing preference with respect to the type of the stimulus employed. Due to the complete decussation of the optical nerves in dolphin brain our results reflected a different specialization of brain hemispheres for visual scanning processes confirming that in this species different stimuli evoked different patterns of eye use. A preferential use of the right eye (left hemisphere) during visual inspection of unfamiliar targets was observed supporting the hypothesis that, in dolphins, the organization of the functional neural structures which reflected cerebral asymmetries for visual object recognition could have been subjected to a deviation from the evolutionary line of most terrestrial vertebrates.     

RFID system for newborn identity reconfirmation in hospital: exposure assessment of a realistic newborn model and effects of the change of the dielectric properties with age

This paper addresses the exposure assessment of RFID devices for newborn identity reconfirmation. To that purpose, a realistic newborn model ("Baby") is used to evaluate by a computational approach the levels of exposure due to these devices. Considering the average technical specifications currently in use, the exposure matrix in Baby shows that the systems comply with the ICNIRP exposure guidelines. As second aim, the effects of the change of the tissue dielectric properties with age on the so called "exposure matrix" (set of induced magnetic and electric field together with the derived values of SAR) is addressed. Specifically, three different approaches proposed in literature for the age variation of the dielectric properties at 13.56 MHz (the working frequency of the RFID systems for these applications) have been implemented using the Baby geometrical model. The related exposure matrices were then compared with the results obtained using the adult properties. No clear trend can be identified on the exposure matrices obtained varying the dielectric properties at 13.56 MHz, although the results could suggest a trend toward the underestimation of the exposure using adult properties.     

Generalization of 'same-different' classification abilities in bottlenosed dolphins

Two bottlenosed dolphins taught to classify pairs of three-dimensional objects as either same or different were tested with novel stimulus sets to determine how well their classification abilities would generalize. Both dolphins were immediately able to classify novel pairs of planar objects, differing only in shape, as same or different. When tested on sets of three objects consisting of either all different objects or of two identical objects and one different object, both dolphins proved to be able to classify 'all different' sets as different and 'not all different' sets as same, at levels significantly above chance. These data suggest that dolphins can use knowledge about similarity-based classification strategies gained from previous training to perform successfully in a variety of novel same-different classification tasks. Visual classificatory abilities of dolphins appear to be comparable to those that have been demonstrated in primates.     

Iron Indices in Bottlenose Dolphins (Tursiops truncatus)

Bottlenose dolphins can have iron overload (that is, hemochromatosis), and managed populations of dolphins may be more susceptible to this disease than are wild dolphins. Serum iron, total iron-binding capacity (TIBC), transferrin saturation, and ferritin were measured in 181 samples from 141 dolphins in 2 managed collections and 2 free-ranging populations. Although no iron indices increased with age among free-ranging dolphins, ferritin increased with age in managed collections. Dolphins from managed collections had higher iron, ferritin, and transferrin saturation values than did free-ranging dolphins. Dolphins with high serum iron (exceeding 300 μg/dL) were more likely to have elevated ferritin but not ceruloplasmin or haptoglobin, demonstrating that high serum levels of iron are due to a true increase in total body iron. A time-series study of 4 dolphins with hemochromatosis that were treated with phlebotomy demonstrated significant decreases in serum ferritin, iron, and TIBC between pre- and posttreatment samples; transferrin saturation initially fell but returned to prephlebotomy levels by 6 mo after treatment. Compared with those in managed collections, wild dolphins were 15 times more likely to have low serum iron (100 μg/dL or less), and this measure was associated with lower haptoglobin. In conclusion, bottlenose dolphins in managed collections are more likely to have greater iron stores than are free-ranging dolphins. Determining why this situation occurs among some dolphin populations and not others may improve the treatment of hemochromatosis in dolphins and provide clues to causes of nonhereditary hemochromatosis in humans.Abbreviations: TIBC, total iron-binding capacityBottlenose dolphins (Tursiops truncatus) are susceptible to iron overload (that is, hemochromatosis).^19,32,33,35 Dolphins with hemochromatosis have high serum iron levels that progress over years, have high transferrin saturation (85% and greater), and are responsive to phlebotomy therapy.¹⁹ Left untreated, dolphins with hemochromatosis are more likely to have increased liver aminotransferases, chronic inflammation, and hyperlipidemia than are healthy controls.³⁵ A 25-y retrospective study of one population demonstrated that 67% of dolphins had excessive hepatic hemosiderin deposition at time of death, 92% of which had hemosiderin deposition in Kupffer cells; hemolytic anemia, anemia of chronic disease, and viral infections were not associated with hemosiderin deposition, and the primary hypothesis is that dolphins in managed collections may be susceptible to iron storage disease.³²The etiology of dolphin iron overload is unknown. The most common cause in humans is hereditary hemochromatosis, which is most often attributed to a point mutation of the HFE gene.¹² Other causes of iron overload include primary liver disease, excessive iron intake, and insulin resistance.^3,36 Comparisons of the HFE gene among dolphins with and without hemochromatosis showed no significant differences (unpublished data), and iron deposition in Kupffer cells (compared with hepatocytes) is not supportive of a hereditary cause.^3,32 Liver enzymes decrease in response to the removal of body iron through phlebotomy; this effect indicates that iron overload leads to liver disease rather than that primary liver disease causes iron overload.¹⁹ At least one dolphin population from which cases of hemochromatosis have been reported have not received iron supplementation for more than 10 y, although the iron content in their frozen–thawed fish diet has not been assessed fully.¹⁹ Dolphins with hemochromatosis have significantly higher 2-h postprandial insulin levels than do controls, suggesting that insulin resistance plays a role in this disease, as occurs in humans.³³In addition to dolphins and humans, iron overload occurs in diverse captive birds, callitrichids, black rhinos, Egyptian fruit bats, lemurs, northern fur seals, California sea lions, tapirs, and Saler cattle.^{5,11,15,18,20,21,23,29,31} Similar to that in other exotic species, iron overload in dolphins is thought to be a disease that is associated with managed care, but comparisons of iron levels among managed collections and free-ranging dolphin populations have been lacking.¹⁹ Further, measurements of serum ferritin, ceruloplasmin, and haptoglobin have not typically been included in iron overload evaluations in dolphins. Although serum ferritin levels can be an indicator of total iron body stores, ferritin also increases in response to inflammation or hemolytic anemia.⁴ In humans, ceruloplasmin is a plasma protein that increases with acute and chronic inflammation and plays a role in iron metabolism. Haptoglobin is a protein that, in humans, decreases with intravascular hemolytic anemia, among other conditions.² As such, concurrent measurements of iron, ferritin, ceruloplasmin, and haptoglobin provide insight into the true cause of changing iron and ferritin levels.Low serum iron is used as a general indicator of inflammation in marine mammals, and return of serum iron to normal levels during illness is seen as a positive indicator for recovery.^13,24 The dynamics of iron, erythrocyte sedimentation rate, and fibrinogen in inflammation have remained important as indicators of dolphin health for decades, yet little has been published about dolphin iron stores and associated acute-phase proteins in the past 30 y.²⁴ One barrier to the use of acute-phase proteins, including C-reactive protein, has been the need for species-specific assays; development of tests that better detect early phases of inflammation and infection could lead to earlier treatment and better outcomes. Other barriers include the need for consecutive samples from dolphins with known health status to validate indicators for inflammation, including ceruloplasmin.To better understand the prevalence of high serum iron and potential risks for hemochromatosis among various dolphin populations, indices of serum iron, ferritin, total iron-binding capacity (TIBC), percentage transferrin saturation, ceruloplasmin, and haptoglobin concentrations were measured in 2 populations of free-ranging dolphins and 2 managed collections, including the cohort of Navy dolphins. These variables were compared by age, sex, and population. Serum ferritin was measured by using a newly developed dolphin-specific assay.     

Importance of spontaneous micronucleated erythrocytes in bottlenose dolphin (Tursiops truncatus) to marine toxicology studies

The objective of the work was to characterize the presence of spontaneous micronucleated erythrocytes (MNES) from peripheral blood of bottlenose dolphins (Tursiops truncatus) to evaluate the possibility to use this species as potential bioindicator of genotoxic compounds. Forty-eight blood samples from 12 bottlenose dolphins were obtain from three Mexican dolphinariums, and from 10 dolphins was possible to obtain more than one sample at different sampling times. Smears were processed and observed with an epifluorescence microscope. The average of MNES and polychromatic erythrocytes (PCE) from the 48 samples was 24.3 +/- 6.1 MNES/10,000 total erythrocytes (TE), and 9.1 +/- 5.5 PCE/1,000 TE. MNES and PCE number did not show differences between gender and age. No variations in the MNES values of the bottlenose dolphins that were sampled more than one occasion were found. Comparisons among dolphinariums revealed differences in MNES frequency, with the highest significant frequency observed in dolphins from dolphinarium "A" (26.0 +/- 5.9 MNES/10,000 TE) than dolphinarium "B" (19.5 +/- 3.1 MNES/10,000 TE) (p < 0.05) and dolphinarium "C" (18.6 +/- 3.5 MNES/10,000 TE) (p < 0.007). The presence of MNES and PCE in the bottlenose dolphin may provide a useful marine mammal model to detect DNA damage by means of micronuclei test in peripheral blood erythrocytes to evaluate genotoxicity and cytotoxicity expositions.     

Sociability of female bottlenose dolphins (Tursiops spp.) and chimpanzees (Pan troglodytes): Understanding evolutionary pathways toward social convergence

On the northern tip of New Zealand's South Island, bottlenose dolphins (Tursiops truncatus) occasionally pass through Admiralty Bay in large, fast-traveling groups of 100 or so individuals. Watching such a group race and splash through the water is reminiscent of a stampeding herd of ungulates, cetaceans' closest terrestrial ancestors. At other times, smaller social groups of bottlenose dolphins appear in the bay and provide a glimpse of the behavioral complexity that dolphins share with their distant relatives, the primates (Fig. 1). Despite being evolutionarily separated for 95 million years and evolving in vastly different environments, cetaceans and primates share striking similarities in behavior, socioecological problem-solving, life-history patterns, and cognitive capacity. By comparing attributes shared by primates and cetaceans, distraction from phylogenetic "noise" is minimized and our understanding of evolutionary pathways is enhanced. In particular, cetaceans provide a powerful outgroup for studying the evolution of primate social organization.