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1.
The Atlantic salmon (Salmo salar) is a freshwater and marine fish of the family Salmonidae, widely farmed in aquaculture facilities in several countries. The salmon are carnivorous, but in aquaculture, alternative foods have been experienced. It is well known that feeding in captivity should cause adaptation and modifications of the morphological characteristics of the oral cavity, especially of tongue; therefore, the aim of this study was to investigate, by light, laser confocal and scanning electron microscopy, the morphological characteristics of the tongue dorsal surface, considering the importance of the correlations between feeding habits and the anatomy of the tongue. Scanning electron microscopy demonstrates the presence of caniniform teeth with oro-aboral orientation surrounded by numerous filiform papillae, single, fused or arranged in row. Oro-aborally, the papillae show an appearance like a rosette and they disappear at level of the root. Light and laser confocal microscopy demonstrates that the mucosa is covered by a non-keratinized stratified pavement epithelium with, in the deepest layer, the presence of a triangular structure whose apex is cranially directed and base facing aborally. In this structure, spindle-shaped cells are present, with a vimentin immunoreactivity, that for their characteristics could be adult mesenchymal stem cells. The obtained data could be useful not only for further studies on the nutrition, but it is interesting the detection of tissues typical of the embryo-fetal phase in the adult specimens tongue, thus giving a basis for studies of potential applications, if any, regarding cell therapies for different clinical indications.  相似文献   

2.
The intestinal tract of the white rhinoceros (Ceratotherium simun) was dissected. We observed a simple structure for the small intestine, duodenum, jejunum and ileum, and a well-developed large intestine, cecum, colon and rectus. The cecum consisted of a small chamber, whereas the colon was much enlarged; notably larger than that of the domesticated horse, which belongs to the same order, Perissodactyla. This suggests that in the white rhinoceros the cecum may be functionally replaced by the well-developed colon which may act as the main fermentation tank in this animal.  相似文献   

3.
利用扫描电镜和光学显微镜对我国岩黄耆属21种植物的花粉形态作了系统观测。结果表明,21种岩黄耆属植物的花粉为长球形,大多具3沟,少数为3拟孔沟,沟长达两极,极面观三裂圆形,赤道面观长球形,沟膜外突或不外突,极轴长15.6~30.25μm,赤道轴长9.0~19.5μm,极轴/赤道轴为1.28~1.85,大小为22.16μm(18.03~27.55μm)×14.32μm(12.13~18.76μm),表面具穿孔状、网穴状、拟网状和网状纹饰。岩黄耆属植物花粉的大小、沟膜和外壁纹饰变异较大,这种变异与该属植物的生态地理分布有关。同时,结果显示岩黄耆属与藏豆属较驴食草属更为近缘,但对其系统位置及亲缘关系的确立,还需要更多的资料和证据。  相似文献   

4.
The intralimb indices and calcaneal linear metrics are known as the reliable predictors of locomotor adaptation in artiodactyls. The osteological features of hindlimb in adult Saiga (Saiga tatarica) were described, and its correlation with cursoriality and habitat adaptation was discussed. Gross anatomy data showed Saiga owned the deep acetabulum as a broad lunate surface, the large acetabular anteversion, the well-developed ischiatic tuberosity and the prominent gluteal lines. It also presented the robust rough line and the strong gluteal tuberosity. A proximodistally elongated eminence located on the cranially distal tibia, which had not been found in goat. The tibial extensor groove was deep. The calcaneal tuberosity was robust. Digital anatomy data showed Saiga owned the higher metatarsal-femur ratio than forest musk deer and sheep. Comparing with wild bovids and sheep, Saiga presented a transitional variation in calcaneal form. The mean greatest length of the calcaneus (GLC) and the height of the sustentacular facet (HSF) in Saiga were shorter than that in sheep and longer than that in wild bovids respectively (F = 587.492; F = 10.264, p < .05). The wild bovids had longer cubonavicular facets than the other two groups (F = 18.587, p < .05). The great metatarsal–femur ratio of Saiga implied a superior cursorial ability and high conservation confronting the different habitats. The calcaneal linear metrics might shed light on lifestyle-related functional adaptation over decades of short-term evolution in the semi-free range environment.  相似文献   

5.
文中对马鹿(Cervus elaphus)精子形态与超微结构进行了研究。马鹿精子经固定、脱水、置换、包埋和聚合,用超薄切片机切片,再用醋酸双氧铀、柠檬酸铅染片,最后于透射电镜下观察其超微结构的变化。观察结果表明:马鹿精子全长(58.75±2.35)μm,由头部(8.93±0.24)μm、颈部(1.00±0.16)μm和尾部(48.18±1.18)μm三部分组成;头部呈扁卵圆状,绝大部分被浓缩且电子密度较高的精核所占据,顶体似帽状扣在精核之上,约占头部的2/3,其前部较为膨大;颈部位于头部和尾部之间,这个区域较短;尾部可分为中段、主段和终段。马鹿尾部轴丝的结构类型为"9+2";微管结构类型为"9+9+2"。  相似文献   

6.
The study of sexual dimorphism in dog anatomy, especially with regard to skeletal elements, has received little attention. The present work focuses on elements of the canine stylo- and zeugopodium, less documented than the skull or pelvis in the literature. In order to identify only sex-dependent effects, we analysed a single breed: the German Shepherd Dog. Data come from 25 dogs, with a balanced sex ratio (12 males and 13 females). Four skeletal elements of the forelimb and hindlimb (humerus, radius, femur, tibia) were each measured using seven linear morphometric variables. Univariate and multivariate analyses were then performed on these 28 variables. For all measurements, males are on average larger than females, with a mean sexual dimorphism ratio of 1.07. Sexual dimorphism is significant for 92.8% of the variables. Except of femoral measurements, diaphyseal values show the highest grade of sexual dimorphism. The mean level of disparity is higher in the forelimb (1.08) than in the hindlimb (1.05). A significant dimorphism is shown for the first component of principal component analyses conducted on each skeletal element, and for the second component with humerus measurements. Discriminant functions for sex identification give success rates included between 82% for the radius and 93% for the femur, the latter providing the highest reported score for sex identification in dogs from any skeletal element. These complementary statistic methods highlight a more dimorphic forelimb in size and a more dimorphic hindlimb in shape.  相似文献   

7.
本试验通过组织学染色及16S rRNA V3~V4区测序研究豆油部分或全部替代饲料中鱼油对中华条颈龟(Mauremys sinensis)肠道形态及菌群结构的影响。选取中华条颈龟雌龟[4龄,平均体重(1 557±307)g]24只,随机分为4组,每组6只。Ⅰ组(对照组)饲喂含1%鱼油的配合饲料(全鱼油饲料,豆油与鱼油的比例为0∶3),3个试验组分别饲喂用豆油替代全鱼油饲料中33%(Ⅱ组,豆油与鱼油的比例为1∶2)、67%(Ⅲ组,豆油与鱼油的比例为2∶1)和100%(Ⅳ组,豆油与鱼油的比例为3∶0)鱼油的饲料。每周喂食2次,试验期为10个月。结果表明:1)Ⅰ和Ⅲ组十二指肠绒毛长/隐窝深度(VH/CD)显著高于Ⅱ和Ⅳ组(P0.05)。2)根据序列相似性97%水平划分,Ⅰ、Ⅱ、Ⅲ和Ⅳ组操作分类单元(OTU)总数分别为396、321、347和331个,特有OTU个数分别为43、3、4和5个,分别被鉴定出139、117、128、120个属。十二肠道优势菌门主要包含拟杆菌门(Bacteroidetes)、厚壁杆菌门(Firmicutes)、梭杆菌门(Fusobacteria)和变形菌门(Proteobacteria)4个门。Ⅱ、Ⅲ和Ⅳ组梭杆菌门和变形菌门所占比例增加,拟杆菌门和厚壁菌门所占比例下降,Ⅲ组厚壁杆菌门和拟杆菌门所占比例与Ⅰ组差距最小。细菌Ace指数和香农指数表现为Ⅰ组最高,其次是Ⅲ和Ⅳ组,Ⅱ组最小;细菌辛普森指数表现为Ⅱ组最大,其次是Ⅲ和Ⅳ组,Ⅰ组最小。由此得出,饲喂用豆油替代67%鱼油的饲料的中华条颈龟的肠道细胞发育成熟度以及菌群结构与饲喂全鱼油饲料的中华条颈龟相近。  相似文献   

8.
9.
The present investigation was designed to describe the surface ultrastructure of the gill system of tilapia Zilli. The gill system is formed from four gill arches and each gill arch carries a row of gill filaments on its convex border and two rows of the gill rakers on its concave border. The quadrilateral interbranchial septum has elevated part at the level of the third gill arch. By SEM observations, the gill arch was divided into three regions: rostral, middle and caudal region. The caudal region contained two characteristic structures: oval leaf‐like structure and rounded‐shaped structure. Each oval leaf‐like structure carried two lateral rows of the triangular pointed spines separated by a median groove. All surfaces of gill arches, rakers and filaments were covered with a mosaic of the polygonal pavement cells, in addition to the opening of chloride cells and mucous cells. The gill arch and gill raker had only one appearance of taste buds named type I. Meanwhile, the filaments contained two types of different appearance of the taste buds named: type I and type II. Type I was the main common and similar to that present in gill arch and raker and characterized by its blunt end, while type II had hair‐like structures that projected from the volcano‐shaped depression. The gill rakers were formed from central axis surrounded by two lateral lobulated regions which carry pointed spines, taste buds and the opening of chloride cells. The surface of triangular lower pharyngeal jaw carries numerous teeth‐like papillae which originated from the socket‐like depression.  相似文献   

10.
This study aimed to evaluate the effect of five salt solutions in the maintenance of morphological features of cortical alveolus, hydration and fertilization capacity of Prochilodus lineatus oocytes. For this purpose, five saline solutions were tested: Ringer's solution, Ringer's lactate solution, Hank's balanced salt solution (HBSS), Hank's balanced salt solution without calcium (HBSS without calcium) and solution for salmonid eggs. Oocytes were maintained for 2 hr in saline solution with controlled temperature subsequently evaluated for hydration, cortical activation and fertilization ability. In the evaluation of the fertilization ability, two controls were used: C1—fertilized oocytes after extrusion—and C2—oocytes kept in ovarian fluid and fertilized after 2 hr. There was a significant reduction in the viability of oocytes C2 (28.8% ± 12.9%) compared to C1 (65.3% ± 26.7%), and no significant differences were found between treatments HBSS and HBSS without calcium and C2. Only HBSS and HBSS without calcium maintained the non‐activated state of the gametes, with a fertilization rate of 16.4% ± 6.7% and 5.6% ± 2.3%, respectively; however, they did not extend the viability of oocytes, such that they continued to undergo degradation during the storage period, similar to oocytes retained only in ovarian fluid.  相似文献   

11.
经对宁夏4个地区1085只家兔和35只野兔的调查,发现有3种双腔属(Dicrocoelium)吸虫:矛形双腔吸虫(D.lanceatum)、东方双腔吸虫(D.orientalis)和中华双腔吸虫(D.chinensis)。其中后2种为宿主新纪录。它们在家兔中的感染率依次为4.2%、1.8%、0.4%,在野兔中的感染率依次为14.3%、5.7%、5.7%。中华双腔吸虫呈纺锤形,体长5.702~6.934mm,体宽1.091~1.549mm,长宽比4.9:1,睾丸并列,阴茎囊椭圆形并达腹吸盘前缘,卵黄腺起自于睾丸之后、卵巢之前水平处;其余2虫种的形态与记载的基本一致。  相似文献   

12.
本试验研究了日粮中氧化鱼油及抗氧化剂对父母代种母鸡繁殖性能及对后代仔鸡的影响,旨在研究父母代营养对后代的影响。200只29周龄Cobb-Avian 48父母代种母鸡分为5个处理,每个处理5个重复,每个重复8只鸡,种鸡日粮分别为2%新鲜鱼油(FO)组、2%氧化鱼油组(OFO)、2%OFO+100 mg.kg-1VE、2%OFO+198mg.kg-1乙氧喹(EMQ)组、2%OFO+100 mg.kg-1VE+198 mg.kg-1EMQ组,后代的仔鸡饲喂完全相同的玉米—豆粕型日粮。结果表明:(1)父母代种母鸡日粮中氧化鱼油降低了母鸡产蛋率(P0.05),入舍母鸡产蛋量(P0.05);(2)父母代种母鸡日粮中氧化鱼油降低了后代仔鸡初生体质量(P0.05);(3)父母代种母鸡日粮中各个氧化鱼油组的后代仔鸡空肠绒毛高度变短(P0.01),绒毛宽度变窄(P0.01);(4)父母代种母鸡日粮中氧化鱼油降低了后代仔鸡0~7日龄平均增加体质量(P0.01)、7日龄平均体质量(P0.05),7~14日龄的平均采食量(P0.01),14日龄平均体质量(P0.01)。结果提示,父母代种母鸡日粮中氧化鱼油具有明显的繁殖毒性,不仅降低了父母代种母鸡的繁殖性能,而且通过影响子代初生体质量以及肠道黏膜的发育,最终导致生长性能下降。  相似文献   

13.
14.
为了探讨火鸡腔上囊的组织形态结构及其发育规律,为火鸡的免疫接种和疾病研究提供理论基础。分别取不同日龄火鸡的腔上囊,常规石蜡组织制片,显微镜下进行对比观察,比较不同日龄火鸡腔上囊的组织形态结构。研究结果表明,火鸡腔上囊的基本组织结构与其它禽类基本相似,从内至外依次由黏膜、黏膜下层、肌肉和浆膜4层组成。与其它禽类腔上囊相比,火鸡腔上囊的黏膜和黏膜下层所形成的纵行皱襞和小皱襞要发达得多;黏膜上皮全部为假复层柱状上皮,黏膜的固有膜内腔上囊小结也相对发达。火鸡腔上囊随着日龄的增加而逐渐发育,母火鸡至208日龄时达最大,公火鸡则迟于母火鸡几周,以后又逐渐退化。  相似文献   

15.
采用扫描电子显微镜,对贺兰山山地疏林草原建群种,优势种、伴生种等10种主要植物的花粉形态进行了 细致的观察,并进行了详细的描述。掌握了它们在扫描电子显微镜下的形态特征。结果表明,在扫描电子显微镜下,花 粉的外壁纹饰非常清晰,萌发器官类型鉴定准确。同时表明这10种归属于不同科、属的植物,其花粉形态均存在明显差异。  相似文献   

16.
Five New World camelids were admitted to the Western College of Veterinary Medicine between 1996 and 2003 for evaluation of femoral fractures. There were three alpacas and two llamas. Four of the animals were female and three were less than 3 months of age. Fracture configurations consisted of distal physeal fractures (three), a comminuted diaphyseal/metaphyseal fracture, and a transverse diaphyseal fracture. Fractures were diagnosed with a combination of physical examination and radiographs in all cases. All five fractures were repaired with internal fixation and three animals were discharged from the hospital with fractures that healed. One cria underwent successful internal fixation but died from pulmonary oedema during recovery from anaesthesia. Postoperative complications were rare and limited to inadequate fracture stability in one alpaca and prolonged recovery to weight bearing in another. One llama with a comminuted metaphyseal fracture, repaired with a 4.5 mm dynamic compression plate, subsequently had catastrophic failure of the bone 17 days after surgery. Overall the clients were pleased with the outcome of discharged animals. Although femoral fractures are considered rare, they pose a unique opportunity for the large animal veterinarian to successfully achieve fracture union with the aid of internal fixation.  相似文献   

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18.
采用扫描电镜(SEM),对内蒙古阿拉善荒漠区10种特有植物的花粉形态进行了详细的观察描述,掌握了它们在扫描电镜水平上的形状、大小、表面纹饰、萌发器官类型及数量等形态特征,为生态建设、环境保护、地质地貌、植物分类及遗传育种等相关研究提供了可靠的孢粉学参考。  相似文献   

19.
The QRS amplitude and polarity were determined in 12-lead electrocardiograms recorded from 22 Boxers with ventricular arrhythmias. Eighty-one percent (18/22) of dogs displayed a positive QRS morphology in the caudoventral leads (II, III, and aVF) and 77% (17/22) of dogs displayed a positive QRS morphology in the left precordial leads (V2-V6). In leads I and V1, the polarity of the QRS complex was variable (positive or negative). To determine if these morphologic features were suggestive of ventricular complexes arising from the right or left ventricle, a comparison was made to the QRS complexes in a pace-mapping study performed in 7 healthy mixed-breed dogs. A total of 3 right and 4 left ventricular sites were paced. None of the left ventricular paced sites resulted in a QRS morphology similar to the most common spontaneous ventricular arrhythmia in the Boxers. In contrast, QRS morphology in each of the 3 right ventricular sites was similar to that observed in the Boxers (P < .033). Each of these produced positive deflections in the caudoventral and left precordial leads, but both positive and negative QRS complexes were observed in leads I and V1 only when the right ventricular septum was paced. This finding suggested that the right ventricular septum might be a site of origin for the ventricular rhythm observed in the Boxers because in the Boxers the polarity of leads I and V1 also varied. Pacing the right ventricular outflow tract always resulted in a negative QRS complex in lead 1, whereas pacing the right ventricular apex always resulted in a positive QRS complex in lead I and a negative QRS complex in V1. However, these locations cannot be excluded as possible sites of origin for the spontaneous ventricular arrhythmias in the Boxers because the arrhythmias could be originating from both of these locations. The spontaneous ventricular arrhythmia of the Boxer is most similar to that of paced ventricular rhythms arising from the right ventricle. More precise localization to a region of the right ventricle such as outflow tract, septal, or apical could not be made.  相似文献   

20.
应用大体解剖学与组织学切片技术,对父母代固始鸡空肠的发育形态学进行了研究,并用Logistic曲线方程对空肠重量增长进行拟合.结果表明:空肠的长度、重量、周长和空肠的绒毛长度、绒毛宽度、隐窝深度、肠腺宽度与周龄呈正相关;空肠指数、空肠的肠腺密度与周龄呈负相关;Logistic方程可以很好地拟合空肠的增重曲线(公鸡R2=0.9968,母鸡R2=0.9891),公鸡的空肠增重拐点是8.26周,母鸡是8.64周.  相似文献   

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