Gross Anatomy of the Portal Vein and its Tributaries in the Opossum (Didelphis albiventris)

The gross anatomy of the portal vein (V. portae) and its tributaries was studied through anatomical methods, i.e. dissection, corrosion and diaphanization, in 45 opossums (Didelphis albiventris). In all animals the portal vein was formed by the junction of the cranial mesenteric, caudal mesenteric and lienal veins (V. mesenterica cranialis, V. mesenterica caudalis and V. lienalis, respectively). Many collateral tributaries were observed running into the portal venous trunk.     

Gross Anatomy of the Penis Development in Zebus*

In twenty-two Brazilian Nelore zebus the following measurments of the penis were made: full length, length of the free part and diameter. Penile length is highly correlated with age and body weight.     

Anatomy of the Canine Skull in Low-grade Otocephaly

An inherited low-grade otocephaly in a strain of Beagles was studied. All cases were “mild” with partial agnathia a constant feature in the adult animal. One case of high-grade otocephaly with aprosopus was recorded in an outcrossed animal. Neonatal mortalities in the low-grade type were associated with gross patency of the parietal fontanelle and hydrocephaly. Enlarged lateral ventricles were found in adult dogs, associated with incomplete union of the cranial sutures and occasional membranous-like paietal bone replacement over the patent fontanelle. Partial agnathia was not obvious in the neonate, but became apparent during postnatal skeletal development. The major anatomical differences in the skulls of these dogs were compared with normal Beagles. Malocclusion of the lower mandible and teeth against the upper jaw during development may have resulted in changes in length and width of the upper jaw and certain cranial structures. It was thought that the maloccluding lower jaw acted as a wedge against the upper jaw during mastication and these abnormal pressures, transmitted in an upward, forward, and outward direction, caused lengthening and widening of the palatine and temporal bones, and lengthening of the premaxilla and nasal bones. The nasopharyngeal meatus and palatine fissures were narrower and elongated. The pterygoid processes were pulled into a more horizontal position. It was suggested that a primary inherited abnormality may cause secondary changes in contiguous structures during development, and differentiation between primary (genetic) and secondary (acquired) anatomical abnormalities should be considered.     

Functional Anatomy and Biomechanics of the Canine Hip Joint

Introduction: In many breeds osteoarthrosis of the hip joint is the most typical orthopaedic disease. Numerous studies concerning etiology, pathogenesis and therapy of this disease still consider an exact congruity to be the basis of a physiological joint function. No data, however, are available as far as the distribution of load in the articular surfaces is concerned. Aims: It was the aim of this investigation to describe the biomechanical features of the canine hip joint as exactly as possible with respect to long‐term and momentary loading. Material and Methods: Hip joints from 43 dogs (bodyweight >20 kg) with an average age of 6 years were investigated. The subchondral bone density was determined with the method of CT‐osteoabsorptiometry. With help of cartilaginous and osseus split lines the preferential orientation of the collagen fibres could be determined. In an in vitro experimental setup the contact areas and the contact pressure distribution within the joint have been measured. Results: In the acetabulum, maxima of subchondral bone density were distributed tricentrically: cranially, dorsally and caudally. In the femoral head, only the area close to the attachment of the ligament was highly mineralized. Cartilagineous and osseous split lines within the acetabulum gave evidence of a long‐term tensile stress. In contrast to these findings, there was no clear preferential orientation in the caput ossis femoris. With load increasing initially isolated contact areas extended and became confluent at a loading force of 75% body weight. Values of maximal joint pressure (maximal joint reaction force applied: 400% bodyweight) reached 8–10 MPa. Discussion: The findings clearly show that the articular surfaces of the hip joint are loaded inhomogeneously. For the first time, it was possible to demonstrate that the healthy canine hip joint is physiologically incongruent. Furthermore, areas of cartilage degeneration within the joint surface coincide with regions that are loaded to a higher extent a priori. From the biomechanical point of view it is recommended that all kinds of acetabular fractures – even those affecting the caudal third of the acetabulum – should be surgically repaired in an adequate way.     

Microscopic Anatomy and Enzyme Histochemistry of the Canine Anal Canal

The microscopic anatomy of the anal canal was studied using routine histological methods and the light microscope in male and female dogs ranging from six months to 10 years of age. Precise anatomical boundaries were established for the zona columnaris , the zona intermedia , and the beginning of the zona cutanea. In an effort to clarify conflicting terminology concerning the anal canal, the term "anal sinus" ( sinus anales ) is applied to the shallow troughs located between the longitudinal mucosal ridges or columns (columnae anales) characteristic of the canine and human zona columnaris ; and the term "anal crypt" is used to represent and distinguish the terminal blind pockets of anal sinuses which extend into the lamina propria of the zona intermedia .
Anal glands were identified routinely in the z. columnaris and z. intermedia of the anal canal; dilated excretory ducts of the anal glands were frequently encountered, often filled with inflammatory cells. PAS-positive but Sudan Black-negative secretion was demonstrated in these ducts as well as within the secretory acini. Sebaceous, circumanal and apocrine sweat glands were restricted to the z. cutanea . Moderate to high alkaline phosphatase activity in the basement membrane of circumanal glands may suggest the presence of myoepithelial cells.     

Gross Anatomy of the Intestine in the Giraffe (Giraffa camelopardalis)

We describe the macroscopic anatomy of the intestine of the giraffe (Giraffa camelopardalis). The small intestine was divided into duodenum, jejunum and ileum as usual. The caecum was attached to the ileum by a long ileocaecal fold, and to the proximal ansa of the ascending colon by a caecocolic fold. The ascending colon was the most developed portion of the gross intestine and had the most complex arrangement with three ansae: the proximal ansa, the spiral ansa and the distal ansa. The proximal ansa completely encircled the caecum, describing a 360° gyrus, and represented the widest portion of the intestine. The spiral ansa was formed by three and a half centripetal gyri, a central flexure and three centrifugal gyri. The last centrifugal gyrus left the spiral and described nine flexures of different form and direction over the left side of the mesentery. The two portions that formed each of these flexures ran parallel to each other. The last part of this gyrus ran parallel to the jejunum. When compared with domestic cattle, giraffe had a comparatively short small intestine and a comparatively long large intestine, with a resulting small ratio of small:large intestine. Reasons are presented why this should be considered a peculiarity of cattle‐like ruminants rather than a different representative of a browser–grazer dichotomy in general.     

Dual-phase CT Angiography of the Normal Canine Portal and Hepatic Vasculature

A dual-phase computed tomography (CT) angiographic technique was developed to image the hepatic and portal vascular systems using a nonselective peripheral injection of contrast medium. The arterial phase of the dual-phase scan imaged the hepatic arteries and veins, and the portal phase imaged the portal vein as well as its tributaries and branches. There were three steps involved in acquiring the dual-phase scan: a survey helical scan for orientation, a dynamic scan for timing, and finally the dual-phase helical scan. Five normal dogs were imaged using a helical scan technique. The timing of the arterial and portal phases of the scan was calculated using time vs. attenuation graphs generated from a dynamic scan. The median time of appearance of contrast medium in the cranial abdominal aorta was 8.6 s and the median time of appearance of contrast medium in the hepatic artery occurred 0.4 s later. The median time of peak enhancement in the cranial abdominal aorta was 12.0 s. The median time of appearance of contrast medium in the portal vein was 14.6 s and median time of peak enhancement was 33.0 s. The dual-phase scans provided excellent vascular opacification. The hepatic arteries, hepatic veins, cranial and caudal mesenteric veins, splenic vein, gastroduodenal vein, and portal vein branches were all consistently well defined. Dual-phase CT angiography is a minimally invasive technique which provides an excellent three-dimensional representation of portal and hepatic vascular anatomy.     

犬嗅觉系统形态解剖学研究进展

通过对近年来犬嗅觉领域研究的汇总,介绍了犬嗅觉系统外部形态学及目前犬嗅觉的研究进展等。进一步归纳总结出犬嗅觉系统的特殊结构特点,为研究犬的强大嗅觉能力提供结构基础,有助于开展犬嗅觉系统功能的研究,以便更深入了解犬嗅觉灵敏的原因,为切实提高犬的工作能力提供理论依据。     

Post-Partum Involution of the Canine Uterus – Gross Anatomical and Histological Features

We aimed to study the normal puerperium in the bitch. Ovariohysterectomy was performed in nine bitches, each at a different day after normal whelping; their genital tract was subject to gross anatomical examination, as well as to histological examination and electron microscopy scanning. Corpora albicans were evenly distributed in the left and right ovaries and placental sites were evenly distributed among left and right uterine horns. Placental sites were initially of dark green to grey colour, later becoming dark brown; their length and height progressively decreased. Height of the myometrium and diameter of the uterine glands progressively decreased. Trophoblast-like cells were consistently observed at the placental sites and on the surface of the interplacental areas, at all time points where hysterectomy had been performed. It is suggested that involution of the canine genital tract can last up to 3 months and is slow. Continuous (up to D84 post-partum) presence of prominent placental sites should be considered a normal feature of canine uterine post-partum involution.     

Evaluation of the Marsh Deer Stifle Joint by Imaging Studies and Gross Anatomy

This study aimed to evaluate the stifle joint of marsh deer using imaging studies and in comparison with gross anatomy. Ten hindlimbs from 5 marsh deer (Blastocerus dichotomus) were used. Radiography, computed tomography (CT) and magnetic resonance imaging (MRI) were performed in each stifle joint. Two hindlimbs were dissected to describe stifle gross anatomy. The other limbs were sectioned in sagittal, dorsal or transverse planes. In the craniocaudal radiographic view, the lateral femoral condyle was broader than the medial femoral condyle. The femoral trochlea was asymmetrical. Subsequent multiplanar reconstruction revealed in the cranial view that the external surface of the patella was roughened, the medial trochlea ridge was larger than the lateral one, and the extensor fossa at the lateral condyle was next to the lateral ridge. The popliteal fossa was better visualized via the lateral view. Sagittal MRI images identified lateral and medial menisci, caudolateral and craniomedial bundles of cranial cruciate ligament, caudal cruciate ligament, patellar ligament and common extensor tendon. In conclusion, the marsh deer stifle presents some anatomical characteristics of the ovine stifle joint.     

Formaldehyde Vapor Levels in a Gross Anatomy Laboratory During Dissection of the Dog

Breathing zone formaldehyde vapor levels were measured in a veterinary gross anatomy laboratory during dissection of greyhound dogs. Measurements were conducted throughout the academic quarter during which dissection took place. Measurement was accomplished using 3 M Company formaldehyde monitors (# 3720). The overall mean time weighed average was 0.197ppm to which students and faculty were exposed a total of 72 hours.     

Gross Anatomy of the Brachial Plexus in the Giant Anteater (Myrmecophaga tridactyla)

Ten forelimbs of five Myrmecophaga tridactyla were examined to study the anatomy of the brachial plexus. The brachial plexuses of the M. tridactyla observed in the present study were formed by the ventral rami of the last four cervical spinal nerves, C5 through C8, and the first thoracic spinal nerve, T1. These primary roots joined to form two trunks: a cranial trunk comprising ventral rami from C5‐C7 and a caudal trunk receiving ventral rami from C8‐T1. The nerves originated from these trunks and their most constant arrangement were as follows: suprascapular (C5‐C7), subscapular (C5‐C7), cranial pectoral (C5‐C8), caudal pectoral (C8‐T1), axillary (C5‐C7), musculocutaneous (C5‐C7), radial (C5‐T1), median (C5‐T1), ulnar (C5‐T1), thoracodorsal (C5‐C8), lateral thoracic (C7‐T1) and long thoracic (C6‐C7). In general, the brachial plexus in the M. tridactyla is similar to the plexuses in mammals, but the number of rami contributing to the formation of each nerve in the M. tridactyla was found to be larger than those of most mammals. This feature may be related to the very distinctive anatomical specializations of the forelimb of the anteaters.     

猫肝外门静脉分流的诊断与治疗

体重为1.7 kg的4月龄英国短毛公猫,免疫完全,定时体内外驱虫.就诊期间表现为精神沉郁、低烧、流涎的症状,进行保守内科治疗但症状未见明显改善,并进一步出现癫痫、视力障碍等症状.采用血液学检查、影像学检查以及CT血管造影方法进行进一步检查诊断,确诊为猫单一性肝外门静脉分流.实行外科手术放置缩窄环,缓慢封闭分流的血管.术...     

Gross Anatomy of the Ringed Seal (Pusa hispida) Gastro‐Intestinal Tract

The gross anatomical structure of the ringed seal (Pusa hispida) gastrointestinal tract is poorly described and often veterinary anatomical terminology is not used. Although the basic abdominal visceral pattern corresponded to domestic carnivores, significant differences were noted. The stomach was an elongated sharply bent tube (u‐shaped) with the pylorus and fundus juxtaposed. The elongated jejunum measured up to 15.6 times body length and had 37 jejunal arteries from the cranial mesenteric artery. The pancreas was asymmetrical with a small right lobe and a large left lobe. The unusually short greater omentum negated formation of deep and superficial leaves. The most remarkable difference was the separation of the liver parenchyma into three physically separate masses, held together by hepatic ducts, veins and arteries. The topography and position of the liver was dependent on the amount of blood in the hepatic sinus (distended hepatic veins and hepatic portion of vena cava). Thus, as the hepatic sinus filled, the lateral liver masses separate from the central mass by moving caudolaterally. This was facilitated by modified coronary and triangular ligaments which did not attach directly to the liver, but instead to the hepatic sinus. These anatomical adaptations are apparently advantageous to ringed seal's survival in a deep marine environment.     

The Surgical Anatomy of the Canine Sacrum for Lag Screw Fixation of the Sacroiliac Joint

One hundred canine sacral bone specimens were examined to identify surgical landmarks that may improve screw placement in sacroiliac repair. A lateral view of the sacral wing was studied, as this structure is most easily identified in the dorsal approach used for sacroiliac repair. The height and length of each sacral wing were measured. Four other features of the canine sacrum were identified and measured in comparison with the sacral wing height and length. The cranial overlap of the sacral wing over the intervertebral space of L₇-S₁ was found to have a mean of 14% of the length of the sacral wing. The ventral overlap of the sacral wing over the pelvic canal was found to be 21% of the height of the sacral wing. The ventral limit of the spinal canal (dorsal limit of the sacral body) was 45% of the sacral wing height. The first pelvic foramen was located at a mean distance of 64% of the sacral wing length and 20% of the sacral wing height. Using these four features, a composite view of the sacral wing is described to illustrate the area of the sacral body where screw placement is optimal.