香鱼消化道及肝脏的形态结构特征

采用解剖及石蜡切片显微技术观察了香鱼消化道及肝脏的组织学结构。香鱼消化道由口咽腔、食道、胃及肠构成。口咽腔大且狭长,其底壁前部有一对粘膜褶,两颌边缘着生宽扁梳状齿,腭骨及舌骨具齿,犁骨无齿;舌由基舌骨突出部分覆盖粘膜构成,舌粘膜上皮为复层扁平上皮,含有较多的杯状细胞和味蕾。食道、胃及肠均由粘膜层、粘膜下层、肌层及外膜构成。食道粘膜层上皮为复层扁平上皮,杯状细胞发达。胃呈V形,由贲门部、胃体部及幽门部组成,胃壁粘膜上皮为单层柱状上皮,贲门部与胃体部的固有层中有胃腺。肠较短,由前、中、后肠构成,肠壁粘膜上皮为单层柱状上皮,其游离面具微绒毛;上皮细胞间有杯状细胞。幽门盲囊有350～400条,其组织学结构与肠相同。肝脏单叶,外被浆膜;肝细胞形态不规则,肝小叶界限不明显。     

双峰驼舌的大体解剖和舌粘膜的组织学结构

目的 研究双峰驼舌的形态结构和舌粘膜的组织学结构.方法 肉眼观察舌的形态结构,用直尺和游标卡尺测量各个参数;光镜下,观察舌粘膜的组织学结构.结果 双峰驼的舌由舌尖、舌体和舌根3部分组成;舌背粘膜厚而粗糙,舌腹粘膜薄而光滑;舌乳头包括丝状乳头、菌状乳头、轮廓乳头、锥状乳头和豆状乳头.舌表面角质化程度高,舌尖有明显的正中沟和横向的皱褶.菌状乳头味蕾不很发达,丝状乳头粗而长;舌根宽而厚,锥状和豆状等机械乳头相当发达,轮廓乳头较大;舌肌的横纹肌发达,味腺只见于舌根部.结论 双峰驼舌的形态学特点和组织学结构与其生长的荒漠、半荒漠环境及摄食多刺而粗糙植物的习性相适应.     

阿尔金山国家级自然保护区纵纹腹小鸮食性的季节变化

2012—2013年间,利用食团分析法对阿尔金山国家级自然保护区纵纹腹小鸮Athene noctua的食性进行分析。共分析343个纵纹腹小鸮食团,鉴定出353个猎物。以个体计,当地纵纹腹小鸮主要取食小型哺乳动物,占95.18%,其次为鸟类,占3.97%,也取食少量昆虫(0.85%)。生物量贡献则以小型哺乳动物为主,占99.35%。纵纹腹小鸮在夏季和冬季就可鉴定的取食动物种类比例组成而言,差异具有高度统计学意义(χ2=52.27,df=4,P0.01)。冬、夏两季纵纹腹小鸮取食哺乳动物的平均胫骨长度差异具有高度统计学意义(P0.01)。全年来看,纵纹腹小鸮取食哺乳动物的胫骨长度平均为19.45 mm±5.84 mm(n=194),主要取食Ⅱ级(10.01 mm~20.00 mm)和Ⅲ级(20.01 mm~30.00 mm)的猎物(分别为46.39%和48.45%)。保护区纵纹腹小鸮的食物生态位宽度以夏季最高(2.583),冬季最低(0.949)。研究结果表明纵纹腹小鸮是机会主义捕食者,根据生境中食物的可获得性改变食性。     

大猫熊消化器官的解剖

(1)大猫熊的牙齿与熊、狗、猫等食肉类动物有很大差别。它的特点是切齿很不发达,并且下啮齿的左右中间齿向后移,构成前后二列,减低了切割能力。臼齿特别发达,臼面广阔,适于磨碎较坚硬的植物性食物。臼面结节顶端尖锐,侧面看似三峰型,有食肉兽的齿型特征。从总的来看,它的齿型应属结构复杂、短冠、杂食兽齿型,强大的短锥形犬齿是与采取植物性食物的生物机能相适应的。 (2)大猫熊肠管较短(比一般食肉兽动物的肠管长),缺少盲肠,但在大小肠交界的粘膜面上有显明的分界线,线的前方(头侧)粘膜有绒毛,线后方(尾侧)无绒毛。关于大小肠分界线的问题,有些书上只记载以迴盲肠口为分界标志,而对肠绒毛的形态变化注意不够。 (3)我们的意见大猫熊输胆管粘膜的螺旋形褶,最初是由粘膜管螺旋状弯曲的环状管互相粘连的结果。人的输胆管粘膜以及某些低等脊椎动物的管状器官(如消化管)也常有类似结构。这些螺旋褶的发生机制有些可能与大猫熊胆管内螺旋褶的形成是相类似的。     

滇金丝猴(Rhinopithecus bieti)子宫颈的大体和显微形态学

本文研究了滇金丝猴子宫颈的形态结构。结果表明,滇金丝猴的子宫颈不发达,呈扁平状结构。不存在子宫颈丘,子宫颈管基本上是直的或稍弯曲;粘膜平滑,腺体和隐窝贫乏。子宫颈外口为较薄的腹侧唇和较厚的背侧唇所包围。背侧穹窿深于腹侧穹窿。复层鳞状上皮与柱状上皮的连接位于子宫颈外口处。子宫颈上皮由纤毛细胞和分泌细胞组成。     

瘰螈属(有尾目,蝾螈科)一新种

作者在贵州省织金县采集到一批蝾螈科瘰螈属动物标本,与该属已知物种比较后,确定其为1新种,即织金瘰螈Paramesotriton zhijinensis sp.nov。新种与尾斑瘰螈Paramesotriton caudopunctatus相似,但新种成体头部后端两侧各有3条退化的鳃迹,明显呈童体型;体背嵴两侧各有1条土黄色纵纹;指、趾两侧无缘膜,无内、外掌突;肛后尾腹鳍褶橘红色或橘黄色,约在后3/4处此颜色消失。本文统计并记述了新种的外形、头骨特征、生物学资料。     

两种容易混淆的重要粉虱的鉴别及重新描记

【目的】梳扁粉虱,又名胶扁粉虱、黑胶粉虱,学名为Aleuroplatus pectiniferus QuaintanceBaker。但由于鉴定错误,一些报道误将山茶褶粉虱Aleurotrachelus camelliae(Kuwana)定为黑胶粉虱。本研究通过比较分析梳扁粉虱和山茶褶粉虱形态差异对这两种粉虱害虫进行了区分。【方法】通过采集梳扁粉虱A.pectiniferus和山茶褶粉虱A.camelliae制作玻片标本观察和扫描电镜观察。【结果】重新描述了其伪蛹形态特征,提供了其寄主植物和地理分布信息及伪蛹生态照和玻片、电镜照片,且对其形态进行了比较分析研究。两种粉虱在胸气管褶和尾气管褶末端都分泌有白色丝状蜡质分泌物,但是体型上山茶褶粉虱要稍大于梳扁粉虱;梳扁粉虱在胸气管孔和尾气管孔末端由3~4个特化齿形成梳状结构,且各腹节具有亚中区凹陷,而山茶褶粉虱没有。【结论】提出将Aleuroplatus pectiniferus QuaintanceBaker中文名统一为梳扁粉虱,而将Aleurotrachelus camelliae(Kuwana)中文名统一为山茶褶粉虱。     

蛙科物种背侧褶组织形态特征

背侧褶是无尾两栖类的重要形态特征,但对于其组织结构和功能缺乏了解。本文运用组织学技术,H.E、AB-PAS和Masson三色三种染色方法对蛙科4属的代表物种滇蛙（Dianrana pleuraden）、阔褶蛙（Sylvirana latouchii）、仙琴蛙（Nidirana daunchina）、沼蛙（Boulengerana guentheri）背侧褶和背部皮肤的显微结构进行了系统的比较研究。结果发现：1）蛙科物种的皮肤腺体单元丰富多样,由黏液腺和颗粒腺组成。其黏液腺均为普通黏液腺,按照其分泌物及分泌细胞形态将黏液腺分为Ⅰ型黏液腺和Ⅱ型黏液腺。Ⅰ型黏液腺在沼蛙和仙琴蛙中缺失,Ⅱ型普遍分布。颗粒腺分Ⅰ型颗粒腺、Ⅱ型颗粒腺及特化颗粒腺,Ⅱ型颗粒腺仅见于仙琴蛙,特化颗粒腺仅见于阔褶蛙和沼蛙的背侧褶;2）滇蛙与仙琴蛙背侧褶基本结构与其背部常规皮肤一致,且两种皮肤结构组成也较为相似,在真皮层下都有一层较厚的脂肪层,滇蛙脂肪层厚度约为真皮层厚度的1.52倍,仙琴蛙脂肪层厚度约为真皮层的1.60倍;阔褶蛙与沼蛙背侧褶基本结构也与其常规皮肤一致,且背侧褶结构组成也较为相似,阔褶蛙及沼蛙真皮层内具有单层排列、集中分布的大型特化颗粒腺,其分泌物为两种颗粒物的混合物。3）蛙科中两种背侧褶结构类型代表了两个进化方向,其功能分别为能量储存和反捕,推测其与环境适应进化相关。     

纵纹腹小、鵰及长耳的卵壳超微结构研究（形目：鸱科）

本文首次报道纵纹腹小、、长耳卵壳的气孔、木栅层、锥体层、乳锥体、壳膜、基底帽等结构的扫描电镜观察,并对不同种类进行分析,初步探讨了它们的分类价值和生态意义。     

小熊猫胃的解剖和组织结构研究

小熊猫的胃属单室腺型胃,它以角切迹为界,可分为胃底部和幽门部两部分。胃壁由粘膜、粘膜下层、肌层和浆膜四层组成。四上皮为单层柱状上皮,具有分泌粘液的功能。胃腺有贲门腺、胃底腺、幽门腺三种,但贲门腺不发达。主细胞、壁细胞和粘液细胞的数量与分布呈现规律性变化。肌层发达,特别是内环行肌发达。并与大熊猫胃的结构作了比较。     

蛇雕消化系统形态学研究

对蛇雕消化系统进行了解剖观察,结果表明：蛇雕有锋利的喙,利于撕裂食物;舌根表面具有尖端指向后方的栉状突,可防止食物滑脱;粗大且收缩性较大的食管,嗉囊发达,肌胃不太发达,相对于体长而言肠管较短,但小肠较发达,具有不发达的双侧盲肠。并与部分食植物的鸟类作了比较。     

短耳鸮消化系统形态学解剖

为了丰富短耳鸮的形态学资料,对其消化系统进行了解剖观察,结果表明:短耳鸮有锐利的角质喙以利于撕裂食物,舌后端左右分叉,而且分叉的两侧各有一排尖端后指的角质栉状突,可以防止食物滑落;食管纵向皱襞发达,有较大的伸缩性,无明显嗉囊,食管胸段粗大。肌胃壁薄而无明显角质膜,用来进行化学消化,而不起研磨作用;肠道较体长略长,其中小肠最发达,具有不甚发达的双侧盲肠。并与部分肉食和植食性鸟类作了比较。     

灰鹤消化系统的形态学观察

本文对灰鹤的消化系统进行了大体解剖和形态学观察,结果表明灰鹤具有发达的舌、小肠、肝脏和胰脏;相对发达的盲肠;但嗉囊不甚发达。     

Contributions to the theory of organic form: The intestinal tract

By making some assumptions concerning the symmetry of certain “classes” of vertebrates and other assumptions concerning the mode of absorption of food by the small intestine, an equation is developed which gives a relation between the length of the small intestine and the total mass of an animal. The equation contains parameters which depend upon the category of vertebrates (carnivorous, omnivorous, etc.) with which the animal is to be associated. The paper also contains a brief discussion of the parameters of the equation and some of the implications which stem from assumptions about their relative magnitudes. In particular, it is noted that the constant of proportionality in the equation which relates intestine length to a power of the body mass is found to be inversely proportional to the square of the “energy content” of the food which makes up the animal's diet. Some suggestions are offered which may lead to an experimental evaluation of the parameters.     

Morphological characterization of the alimentary tract of Antarctic fishes and its relation to feeding habits

Summary Morphological and morphometric characteristics of the alimentary tract in 22 species of carnivorous antarctic fishes were studied. It is shown that all of these species have similar, well-developed Y-shaped stomachs with generally thick (0.5–1.0 mm) walls. The relative stomach lengths are also similar, ranging from 9.8 to 22.2% of body length. Relative intestine lengths, a characteristic frequently used as an indicator of the kind of food eaten by a species, are also remarkably similar among most species (31 to 67%). Notothenia gibberifrons, a conspicuous benthos feeder, has a significantly longer intestine (91%), probably as an adaptation to the quantity of undigestible material (mud) incorporated with its faunal prey. These values fit within or below the limits (60–150$) of relative intestine length described in the literature for carnivorous fishes. The number of pyloric caecae is in general relatively low and fairly constant in each species. It is concluded that the morphological features studied could represent similar adaptations of these antarctic fishes to a similar carnivorous diet.     

Excretion of bisphenol A-glucuronide into the small intestine and deconjugation in the cecum of the rat

The environmental estrogen bisphenol A (BPA) is regarded as a modulator of endocrine systems and has been reported to have adverse effects on the reproductive organs of animals. In rats, BPA is metabolized to glucuronide by UDP-glucuronosyltransferase UGT2B1 in the liver and excreted into the bile. In the present study, we found that most of the bisphenol A-glucuronide (BPA-GA) excreted into the small intestine was deconjugated in the contents of the cecum. After BPA administration, BPA-GA was (immediately should be 15 min) found in the contents of the upper part of the small intestine, and then it moved to the lower part of the small intestine. However, only free BPA was found in the content of the cecum, and there was smaller amount of free BPA in the colon contents, indicating that BPA had been reabsorbed in the colon. BPA-GA was deconjugated by extract prepared from the cecum content which included highest beta-glucuronidase (beta-Gase) observed in Western blot analysis using antibodies against bacterial beta-Gase.These results indicate enterohepatic circulation of BPA and suggest that the adverse effects of BPA are enhanced by repeated exposure.     

Characterization of intestinal microbiota and response to dietary virginiamycin supplementation in the broiler chicken

The inclusion of antibiotic growth promoters, such as virginiamycin, at subtherapeutic levels in poultry feeds has a positive effect on health and growth characteristics, possibly due to beneficial effects on the host gastrointestinal microbiota. To improve our understanding of the chicken gastrointestinal microbiota and the effect of virginiamycin on its composition, we characterized the bacteria found in five different gastrointestinal tract locations (duodenal loop, mid-jejunum, proximal ileum, ileocecal junction, and cecum) in 47-day-old chickens that were fed diets excluding or including virginiamycin throughout the production cycle. Ten libraries (five gastrointestinal tract locations from two groups of birds) of approximately 555-bp chaperonin 60 PCR products were prepared, and 10,932 cloned sequences were analyzed. A total of 370 distinct cpn60 sequences were identified, which ranged in frequency of recovery from 1 to 2,872. The small intestinal libraries were dominated by sequences from the Lactobacillales (90% of sequences), while the cecum libraries were more diverse and included members of the Clostridiales (68%), Lactobacillales (25%), and Bacteroidetes (6%). To assess the effects of virginiamycin on the gastrointestinal microbiota, 15 bacterial targets were enumerated using quantitative, real-time PCR. Virginiamycin was associated with increased abundance of many of the targets in the proximal gastrointestinal tract (duodenal loop to proximal ileum), with fewer targets affected in the distal regions (ileocecal junction and cecum). These findings provide improved profiling of the composition of the chicken intestinal microbiota and indicate that microbial responses to virginiamycin are most significant in the proximal small intestine.     

Morphometrics of the avian small intestine compared with that of nonflying mammals: a phylogenetic approach

Flying animals may experience a selective constraint on gut volume because the energetic cost of flight increases and maneuverability decreases with greater digesta load. The small intestine is the primary site of absorption of most nutrients (e.g., carbohydrates, proteins, fat) in both birds and mammals. Therefore, we used a phylogenetically informed approach to compare small intestine morphometric measurements of birds with those of nonflying mammals and to test for effects of diet within each clade. We also compared the fit of nonphylogenetic and phylogenetic models to test for phylogenetic signal after accounting for effects of body mass, clade, and/or diet. We provide a new MATLAB program (Regressionv2.m) that facilitates a flexible model-fitting approach in comparative studies. As compared with nonflying mammals, birds had 51% less nominal small intestine surface area (area of a smooth bore tube) and 32% less volume. For animals <365 g in body mass, birds also had significantly shorter small intestines (20%-33% shorter, depending on body mass). Diet was also a significant factor explaining variation in small intestine nominal surface area of both birds and nonflying mammals, small intestine mass of mammals, and small intestine volume of both birds and nonflying mammals. On the basis of the phylogenetic trees used in our analyses, small intestine length and nominal surface area exhibited statistically significant phylogenetic signal in birds but not in mammals. Thus, for birds, related species tended to be similar in small intestine length and nominal surface area, even after accounting for relations with body mass and diet. A reduced small intestine in birds may decrease the capacity for breakdown and active absorption of nutrients. Birds do not seem to compensate for reduced digestive and absorptive capacity via a longer gut retention time of food, but we found some evidence that birds have an increased mucosal surface area via a greater villus area, although not enough to compensate for reduced nominal surface area. We predict that without increased rate of enzyme hydrolysis and/or mediated transport and without increased passive absorption of water-soluble nutrients, birds may operate with a reduced digestive capacity, compared with that of nonflying mammals, to meet an increase in metabolic needs (i.e., a reduced spare capacity).     

ECOLOGICAL ASPECTS OF ADAPTIVE RADIATION IN BIRDS

1. Relatively few birds feed heavily upon green-plant materials, though a number may take substantial numbers of buds. Birds appear not to possess adequate gut biota to break down cellulose efficiently, and even it they did, this system would not be compatible with efficient flight, on account of the long processing times required. 2. Birds have stronger adaptations toward feeding upon seeds and make a particularly heavy impact upon seeds in trees and on those in widely scattered or unpredictable crops. 3. Several families, mostly of tropical distribution, feed primarily upon fruit. Again, they are most successful in exploiting resources reached only with difficulty by other groups. A similar pattern holds for nectar stores. In the case of fruit and nectar, evolutionary complications result because the plants compete for seed dispersers and pollinators. 4. Most primarily herbivorous species feed their young partially or totally upon insects or other animal foods. Only a few species are able to fledge upon an entirely herbivorous diet, and those that do so often have extremely long fledging periods, which subject their young to high rates of predation unless the parents nest in places inaccessible to predators. 5. In general, herbivorous birds make a heavy impact relative to other animals only when they exploit resources that the other groups have difficulty in obtaining (hard to reach, or widely scattered in space and/or time). 6. Insects are exploited by more families of birds than any other food category. Birds are of greatest relative importance in capturing insects on the wing and in arboreal locations. Other terrestrial invertebrates are probably taken by techniques similar to those used for insects. 7. A variety of species take invertebrate prey along the water's edge or in shallow water. 8. Almost without exception, vertebrate prey is of small size, in part a function of the size of birds. Occasionally predation upon small terrestrial vertebrates may be relatively heavy, generally in outbreak situations. 9. Several families feed exclusively upon fish, crustacea, squid, and other aquatic prey. Some indirect evidence suggests that exploitation of these resources may sometimes be heavy, though there is little evidence that these groups often make an appreciable impact upon this food source. 10. Birds appear to be among the most important scavengers of animal remains. 11. Like the herbivorous birds, carnivorous birds appear to exert their greatest impact upon resources that are hard to reach or are widely scattered in space and/or time. 12. One-third of the avian families feed regularly on a variety of resources, as recognized in Table I. Most of these families specialize upon resources located in certain areas (ground, water's edge, trees, etc.). Only 13% of these families regularly use such a wide range of foods that they transcend both of these considerations (food type, segment of the habitat). In very few cases (5 %) does this designation result from some species of a family specializing upon one category of food and others using a different category. 13. There have been few large (> 20 kg), primarily herbivorous birds, though there have been several large omnivorous species. Large carnivorous species have been even rarer. All of these large species have been flightless, and in most cases they have occurred when or where large mammals were scarce or absent. 14. Birds have made extremely limited use of subterranean areas, caves, or deep water, and adaptations facilitating other types of life appear to be virtually incompatible with success in these situations. All these areas are characterized by a rapidly decreasing food gradient. 15. Bats exploit certain, but not all, of the food resources regularly exploited by birds. The resources not used by bats that are exploited by birds are those that are available over a full 24 h period; thus, bats' nocturnal habits do not provide them with an advantage in exploiting them. 16. Insects also use some of the resources exploited by birds. With few exceptions, insects are smaller than birds or bats. Considerable indirect evidence is consistent with the argument that the segregation in time, resource type, and size of flying animals is at least in part caused by competition. 17. While selection for anti-predatory mechanisms can be surmised, the reciprocal density relationships frequently noticed between birds and other organisms suggest that they arise from competition, rather than predation. 18. Most information suggests that interactions between birds and other animals of the same trophic level are usually, though not invariably, over food. 19. The types of relationship existing between birds and other organisms described above are repeated in a variety of other animal groups, though they clearly are not ubiquitous in the animal kingdom.