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Objective: To investigate topographic and age-dependent adaptation of subchondral bone density in the elbow joints of healthy dogs by means of computed tomographic osteoabsorptiometry (CTOAM). Animals-42 elbow joints of 29 clinically normal dogs of various breeds and ages., Procedures: Subchondral bone densities of the humeral, radial, and ulnar joint surfaces of the elbow relative to a water-hydroxyapatite phantom were assessed by means of CTOAM. Distribution patterns in juvenile, adult, and geriatric dogs (age, < 1 year, 1 to 8 years, and > 8 years, respectively) were determined and compared within and among groups., Results: An area of increased subchondral bone density was detected in the humerus distomedially and cranially on the trochlea and in the olecranon fossa. The ulna had maximum bone densities on the anconeal and medial coronoid processes. Increased bone density was detected in the craniomedial region of the joint surface of the radius. A significant age-dependent increase in subchondral bone density was revealed in elbow joint surfaces of the radius, ulna, and humerus. Mean subchondral bone density of the radius was significantly less than that of the ulna in paired comparisons for all dogs combined and in adult and geriatric, but not juvenile, dog groups., Conclusions and Clinical Relevance: An age-dependent increase in subchondral bone density at the elbow joint was revealed. Maximal relative subchondral bone densities were detected consistently at the medial coronoid process and central aspect of the humeral trochlea, regions that are commonly affected in dogs with elbow dysplasia.

The objective of this study was to functionally characterize the distal radioulnar ligament connecting the distal ends of canine antebrachial bones. The ligament has been investigated histologically in five adult dogs. After decalcification and standard paraffin embedding, 5-microm-thick sections have been stained with Hematoxylin/Eosin, Resorcin/Fuchsin, Astrablue/Nuclear-fast-red, Astrablue/Orange G. The distal radioulnar ligament can be divided into two parts, a proximal, 'interosseous' and a distal 'articular'. The former as a connecting structure experiences almost exclusively tensile stress in a proximolateral direction. The latter with an additional meniscal function is loaded in a combined tensile and compressive way. These findings can be explained with the characteristic valgus conformation of the canine carpal joint.

Objective: To validate mutual information criterion as a ready-to-use technique for automated alignment (ie, registration) of 3-dimensional (3-D) multimodal image data of the head of cats and dogs., Sample Population: Corresponding 3-D magnetic resonance imaging (MRI) and computed tomography (CT) brain scans of a 6-month-old Doberman Pinscher with a brain cyst; CT images of the head of a European shorthair cat with a meningioma before and immediately, 3, and 6 months after surgical resection; and CT and corresponding stacked anatomic cryosection images of the entire head of a 2-year-old sexually intact female Beagle., Procedure: All images were matched retrospectively by use of an in-house computer program developed on the basis of a mutual information image registration algorithm. Accuracy of the resulting registrations was evaluated by visual inspection., Results: All registrations were judged to be highly accurate. Additional manual corrections were not necessary., Conclusions and Clinical Relevance: Mutual information registration criterion can by applied to 3-D multimodal head images of cats and dogs for full automatic rigid-body image registration. The combination of such aligned images would considerably facilitate efforts of veterinary clinicians as indicated by its widespread use in brain surgery and radiation therapy of humans.

There are a number of differences between the claws of the front and hind limbs in cattle concerning macroscopic shape, chemical and physical properties of claw horn and epidemiological data. Front claws have superior data in almost every respect. Virtually no information is available on the mechanical stability of the suspensory apparatus of the third phalanx. It was the objective of this study to develop a method to measure the maximum strength (N/mm2) of the suspensory apparatus of the bovine distal phalanx. This apparatus includes all layers of tissue such as bone, corium, corioepidermal junction and wall horn. The feet of 13 clinically healthy beef bulls were collected from the local abattoir. Testing was performed in three locations of the wall segment (dorsal, abaxial, axial) in a material testing machine. The corium and the corioepidermal junction were set under increasing tension until failure occurred. Maximum stress was recorded. The values ranged between 2.47-3.13 N/mm2 (dorsal), 4.08-4.87 N/mm2 (abaxial) and 2.27-2.66 N/mm2 (axial). No differences could be validated statistically between front and hind claws and between lateral and medial claws respectively. Abaxial ultimate stress values were significantly higher than dorsal and axial ones. Between the two a statistical difference could not be validated. Most of the specimens (57.1%) were torn apart at the corioepidermal junction, almost a quarter of the samples (27.6%) were to a degree disrupted at the corioepidermal junction and to a certain extent in the deeper layers of the corium. A few samples showed disruption within the horn (11.5%) or at the attachment of the third phalanx (3.8%). Biomechanical features of the experimental set-up are discussed. The biological significance of these findings is that the body weight and the additional dynamic loading is predominantly taken over by the abaxial part of the claw, while the dorsal and axial aspects are less loaded.

Investigations of the pathophysiology of ocular diseases require a detailed knowledge of the microanatomy of the eye. The available information is still inadequate for the equine retina despite the importance of eye diseases in equine medicine. Here we provide a comprehensive analysis of the histologic features of the horse eye as a reference for future studies. Thirty normal eyes of 15 healthy horses were examined immediately after slaughter. The retina of the horse differs considerably in the degree and quantity of neurons and glial elements as well as in vascular patterns compared to the retina of other domestic animals. Morphometric analysis revealed that the thickness of the retina varies between 80 microm at the ora serrata and 250 microm medial to the optic disc. Approximately 90% of the equine retina is comparatively thin (< 130 microm). This is a physiologic response to the distance that oxygen can diffuse in avascular retina. Ganglion cells form a single layer in all parts of the retina. The majority of ganglion cells are very large Nissl-positive cells. Small Nissl-negative ganglion cells are less abundant. A high ganglion cell density is found only in the central area. Vascularization is virtually absent from the retina with the exception of a narrow strip around the disc of the optic nerve, as revealed by lectin histochemistry. Light microscopy of the eyes of older horses repeatedly revealed cystoid degenerations in the retina adjacent to the pars plana of the ciliary body, as well as a destruction of the regular layering of the peripheral region of the retina.

The origin and attachments of the muscles of the external nose were examined in 17 pigs comprising both sexes and different age groups. The modification of the porcine nasal apex to the snout-disc leads to different functional aspects of the muscles of the external nose. Accordingly, all these muscles are attached to the snout-disc. Only the nasolabial levator and caninus muscles are also attached to the upper lip. In addition, the snout-disc includes an intrinsic muscle, the nasal muscle. With regard to morphological and functional aspects, the nostrils can be divided into two parts. The superficial part consists of muscle and connective tissue and is dilated by the cooperative contraction of all muscles of the external nose. In contrast, the second and cartilaginous part of the nostrils dilates less readily, through contraction of the rostrally located deep fibres of the levator nasolabial muscle. As an adaptation for rooting, a special supportive system for muscles of the external nose has developed in pigs, including osseous (eminentia canina) and muscular (muscular slip of the m. levator labii superioris attached to the nasal bone, species-specific development of the m. levator nasolabialis) structures. The observed cartilaginous connection between the ventral lateral nasal and the vomeronasal cartilages suggests another transport mechanism for odours into the vomeronasal organ. Due to this connection, movement of the snout-disc and the cartilages of the external nose could imply passive movement of the vomeronasal cartilage and therefore of the vomeronasal organ.

The "Visible Animal Project" (VAP) is comprised of axial anatomic cryosections and corresponding CT and MR images of a mature dog. The digital database is used for the creation of three-dimensional computer graphics of canine anatomy. The technique of cryodissection is described in detail. The combining of the corresponding CT and MR images, and cryosections as well as the data processing for the creation of three-dimensional reconstructions is presented and examples are shown. For the first time a complete high-resolution three-dimensional database of a dog is available, which can be used as the base for further high quality three-dimensional reconstructions, similar to the "Visible Human Project" (VHP).

The aim of this work was to investigate the postnatal development of the feline spinal cord. Our study showed that the main period of growth leading to the cervical and lumbar enlargements begins after birth and is completed at the age of 5-6 months. Comparing the relationship between the length of the spinal cord and the vertebral column, we found that in contrast to the adult cat, in the newborn cat, length, area and volume of segments show similar values along the spinal cord. This also applied to the length of the vertebrae. Due to a heterogeneous growth, not all segments of the spinal cord end up situated cranial to their corresponding vertebrae. As a consequence, the end of the conus medullaris is still located within the sacral canal in animals older than 2 months. These findings strongly propose that injection into the vertebral canal of the cat have to be performed caudal to the sacral vertebrae.

Fractures of the first two cervical vertebrae, atlas and axis, may occur in foals for different reasons, e.g. in cases of a fall, going head over heels or when being hit by a hoof. The tentative clinical diagnosis can be confirmed by x-raying the standing animal, with aid of computed tomography in the anaesthetized foal respectively. The growth plates however, and their time of closure have to be considered when interpreting radiographs. In the atlas there are two ventrolateral plates and one dorsomedian cartilagineous plate. Only the dorsal plate, however, can be found in the dorsoventral projection up to an age of about 12 months. The ventrolateral growth plates which have closed at about six months of age cannot be seen in either ther dorsoventral or laterolateral projection. In transversely oriented CT-scans all of the three centres of ossification can easily be made visible in the atlas. In the axis the cartilagineous gaps between the dens axis and the cranial epiphysis as well as the cranial and caudal epiphyseal growth plate can be shown in normal x-radiographs in both planes of projection. Besides this there are growth plates between the corpus vertebrae and the arcus vertebrae in the axis which cannot be seen in either radiographic projection. They become clearly visible in transversal CT-scans and are ossified at the age of three to four months. At the end of the first year the growth plates between the dens axis and the cranial epiphysis have closed. The cranial and caudal epiphyseal plate are gone at an age of about four to five years.

102 ophthalmoscopically healthy cats of both sexes, variable age and different breeds were examined gonioscopically. The examination included 70 European Domestic Shorthaired Cats, 24 Persian Cats, four Chartreuse Cats and three Siamese Cats. A distinct difference in number and distribution of fibers of the pectinate ligament was seen between different breeds. In Persian and Siamese Cats the pectinate ligament contains only a third of the fibers which are found in European Domestic Shorthaired Cats. However the fibers are thicker and less sprouted. In addition it was possible to prove an age-related development of the pectinate ligament. While the final number of fibers was seen to be already present in young cats the diameter of fibers increased with age. These findings were confirmed histologically (by stereo dissecting microscopy) light microscopy and scanning electron microscopy). Furthermore the two-layer-structure of the pectinate ligament in the cat was described for the first time.

Membrane structures of different types of cells are imaged in the nanometer regime by scanning force microscopy (SFM). The images are compared to those obtained with a scanning electron microscope (SEM). The SFM imaging can be done on the outer cell membrane under conditions that keep the cells alive in aqueous solutions. This opens up the possibility of observing the kinematics of the structures that determine the interaction of a cell with its environment. Therefore, STM observations, together with information obtained with the electron microscope, open up new ways of studying the development of biological structures. With the currently possible resolution, the SFM gives access to processes such as antibody binding or endo- and exocytosis, including processes correlated to the infection of cells by viruses.

A light and electron microscopic study was carried out on pigs experimentally infected with Eperythrozoon (E.) suis during the acute and chronic phase of infection. During the acute phase Eperythrozoon organisms can be recognised by light microscopy as bright to dark orange points or circles. In contrast, in the chronically infected pigs E. suis appear as bright yellow or green small dots on the edge of the erythrocytes or in the plasma. By scanning electron microscopy, immature, juvenile and mature forms of E. suis could be seen on the same erythrocyte during the acute phase. In chronically infected pigs ring-shaped, rounded resting-stage forms, measuring about 1 micron in diameter, can be observed.

Excessive fat deposition prior to calving and a negative energy balance post partum predispose the high producing cow for an intensive postpartal lipolysis and for the health problems resulting thereof. It was postulated that a well proliferated ruminal mucosa at the beginning of lactation could improve the energy supply by stabilizing the pH of the rumen content with energy rich feed and by providing a high absorption capacity for volatile fatty acids. Results of earlier experiments dealing with this problem are reviewed. Furthermore there is described a pilot experiment with 9 dry cows, which was directed to stimulate rumen mucosa growth ante partum by a low energy ration (roughage) during the first half of the dry period and a high energy ration during the last 3 to 4 weeks prior to calving, without inducing a fat cow. The ruminal mucosa reacted to that feeding regimen as expected and desired. The body weight of 3 cows in moderate and 4 cows in medium body condition increased by 7.2% or 3% during 8 to 11 or 7 to 9 weeks respectively. One of two fat cows lost 4.9% of her body weight within 8 to 9 weeks while the condition of the second animal remained unchanged. No problems were observed at calving. A further progress is expected by feeding the dry cows in two groups with different rations according to their body condition at the end of lactation. Results of experiments as well as practical experiences show that no more than 8 to 10 days are necessary to adapt the ruminal flora to a mixed ration (roughage + concentrates).(ABSTRACT TRUNCATED AT 250 WORDS)

The kidney is a composite organ, the specific activities of which are attributable to the peculiar construction of the individual components of the glomerula, nephrons and collecting tubules. This comprehensive review will address the essential physiological mechanisms of urine formation, such as filtration, secretion, reabsorption and concentration, and correlate these functions to morphological structures where possible. The complex structure of the renal glomerulus as the basis for the formation of primary urine (blood-urine barrier) will be documented on the basis of electron micrographs. In addition to this, the ultrastructure of the epithelium in the various tubular segments and collecting tubules will be discussed from a histophysiological stand-point, including its significance in the excretion of waste substances and maintenance of a constant fluid environment in the body (Homeostasis).

The effect of extracoporeal shock waves on the liver and the gallbladder wall was compared in two groups of dogs exposed to 1500 shock waves generated in an electrohydraulic lithotripter with 15 kV and 80 nF. The waves were focused on the gallbladder wall. In the experimental group, a shock wave burst of 10 consecutive waves with an interval of 10 ms between the waves was administered each second; in the control group, single shocks were released each second. The day following shock wave exposure, the dogs were anaesthetized, killed and then dissected. In the liver, subcapsular and intraparenchymal focal haemorrhages occurred in the high pressure field and venous thrombi in portal veins. There was a nonsignificant trend towards an increased number of venous thrombi after burst application. The gallbladder wall was haemorrhagic and oedematous, the mucosa was ulcerated in the focal area; blood clots were found in nearly all gallbladders. No differences were detected between the groups. The free plasma haemoglobin was only increased after fast shock wave administration. Increased haemolysis and the trend towards an increased number of thrombi favour cavitation as a mechanism of shock wave damage. The similar extent of tissue damage suggests that shock wave bursts can be applied for gallstone destruction in humans if the major liver vessels are kept out of the high pressure field.

Shock waves are known to generate cavitation in vitro. In vivo, extracorporeal shock waves may cause haemorrhages in tissues. Two types of changes were detected by conventional, real-time B-scan ultrasound when shock waves were administered to 5 piglet livers in vivo: transient changes consisting of bright signals in intrahepatic branches of the portal vein and tributaries of the hepatic vein, presumed to originate from gas bubbles, and stationary changes consisting of brightening of the area along the long axis of the high pressure field, presumed to indicate an increased number of gas-filled bubbles in this area. Transient changes appeared from the start of shock wave administration; bright signals were seen in liver vessels for several hundred microseconds before they were flushed away with the blood flow. Stationary changes appeared later, increased in intensity over several hundred shock waves and persisted for minutes after cessation of shock wave administration. Both types of signals were interpreted as direct evidence that lithotripter shock waves generated cavitation in vivo. Similar signals were received in the partly degassed water of the lithotripter tub. At autopsy of the piglets, focal intralobular haemorrhages and thrombi of portal veins were detected in the shock wave path. The occurrence of cavitation and tissue damage in the same gross area suggests that cavitation might be involved in the generation of tissue damage by shock waves.

In animal experiments marked and characteristic changes of lymphocytes could be observed with electronmicroscopic methods due to aldosterone and potassium canrenoate. These results may be a further reference to an immunosuppressive effect of aldosterone and spirolactone derivates. The electronmicroscopic study of thoracic duct cells of a patient suffering from multiple sclerosis and treated with aldosterone and potassium canrenoate showed changes of the morphological structure of small lymphocytes, which was interpreted with a lymphoclastic effect of this substances on lymphocytes.

Chick embryos were treated on day 17 of incubation with 32.8 mumol thiourea or 18.9 nmol L-thyroxine. As was already known from previous studies, hatching was delayed and accelerated, respectively, under these conditions. The premature induction of hatching by L-thyroxine was accompanied by an advanced development of the pulmonary structure and of the circulation and by a premature absorption of the parabronchial liquid. Thiourea exerted an opposite effect on these parameters. In several cases the structural formation of the parabronchii was suppressed after treatment with thiourea. Furthermore, parabronchial liquid accumulated in those embryos, the hatching of which was suppressed. It is suggested that these changes represent a toxic effect of thiourea rather than a retardation of pulmonary development.

Syngeneic and allogeneic grafts of segments of the thoracic duct from rats were investigated in the first fifteen days after transplantation. The patency rate--evaluated by the passage of blue dye--of the allogeneic transplants was almost equal to that seen in the syngeneic grafting. By direct exploration there were no changes to be seen in the syngeneic and allogeneic transplants. Investigations by electron microscopy showed no major reactions to the syngeneic grafts during the observation time: The endothelium always was completely detectable and the subendothelial layer of collagen fibrils was not dislocated. By contrast, the allogeneic transplants showed considerable alterations as disintegration of the collagen fibrils and a partial loss of endothelium occurred after eight to ten days. After fifteen days, however, the formation of a neointima could be demonstrated. Despite the observed alterations there was no loss of function in the allogeneic transplants.

Fertile eggs from Bovans hybrid were treated with dexamethasone on day 17 of incubation. This treatment resulted in a stimulation of the surfactant synthesis as recorded by the increased uptake of 14C-choline into the pulmonary phosphatidylcholine and the accumulation of lipoid vacuoles. On the other hand, dexamethasone caused a delay in pulmonary fluid absorption till day 19. This delay seems to be caused by a retarded onset of lung circulation. This conclusion has been derived from the lowered pulmonary hemoglobin content at this developmental stage. On the basis of the activities of ornithokallikrein and the angiotensin converting enzyme, ornithokinin may be involved in the retarded onset of circulation.

The ultrastructure of granules in the secretory cells of the endosalpinx of 20 Merino ewes was examined on days 1, 2, 3, and 4 post coitum. Based on the different frequency of granules of different size and structure on days one to four post coitum, one can assume that the ovoid, membrane-bounded secretory granules mature in five successive stages. In stage I small, electron-lucent vesicles with a finely granulated and filamentous content become apparent, initially in the neighbourhood of the Golgi complex. In stage II the granules become larger and progressively more electron-dense by an increase of the granulated material. In stage III, the primarily granulated content forms membranes, that lie in characteristic stacks at different angles to one another, separated by electron-dense areas. This structure fragments when the granule comes to lie beneath the surface of the cell (stage IV) and opens into the lumen of the oviduct, where its content is discharged in membrane fragments or vesicles (stage V). This discharge is mainly observed shortly before the egg is transported into the uterus.

The stimulation of gastric secretion is regulated by neurovagal, endocrine and immunological reactions. During the gastric phase of digestion, especially acetylcholin, gastrin and histamin react as main transmitters, activated by mediators (prostaglandines, leucotrienes, lipoxygenases). The dominant role of nervus vagus has to be seen in the transactions of vago-vagal reflexes, the stimulation of gastrin liberation by an non-cholinergic mechanism and the regulation of the gastric microcirculation. The antrum pylori can be seen as an immunological area of reception, where immunological active cells (macrophages, NK-lymphocytes and T-lymphocytes) are recognizing antigens (e.g. food antigens). These immunocytes induce a cascade of endocrine and exocrine mechanisms of digestion. Mastcells, located intra-and extraepithelial, take a regulatory influence in producing histamins, leucotrienes and also prostaglandines.

By means of electron microscopy and ultrahistochemical research it has been attempted to detail the structure and explain the function of the pleural tufts of the parietal pleura present in the ventral mediastinum of dogs. This led to the discovery that the varions forms present for the surface-enlarging pleura protusions in actuality exhibit corresponding morphological characteristics. As a special formation of the serous lamina of parietal pleura, they are covered by an occasionally incomplete mesothel unit. The parenchyma of these organs is compinsed of a macrophage-rich outer border zone and of a vessel-canying central zone. The experimental in vivo application of cationized ferritin in the pleura-space clearly indicated a high resorptive metabolism of the mesothel and of the pluripotential mesenchym cells. The higher incidence of lymphoplasmatic cell-forms in the proximity of the central vessels along with leucocytic cell infiltrations fulfill an immunocellular and phagocytic function. The structure of the cell population of the pleural tufts partaking on the resorption of matter out of the pleural space has been discussed in detail. The in vivo application of a cationized ferritin solution for the purpose of studying these resorptive processes has been critically judged.

The effect of shock waves on normal canine kidneys was examined in three groups of dogs whose right kidneys were exposed to 500, 1500, or 3000 shock waves. Autopsy was performed 24-30 h later. The kidneys were enlarged with haemorrhages in the outer and inner renal capsule and intraparenchymally. Macroscopically intraparenchymal haemorrhages were restricted to the high pressure field of the shock wave and consisted of haematomas up to 18 mm diameter (most frequently 6 mm or less) and diffuse haemorrhages. Histologically, haemorrhages were shown to originate from interlobular and arcuate veins. Venous thrombosis, tubular dilatation, and diffuse interstitial haemorrhage occurred in the same area. The number of haematomas was larger, and diffuse haemorrhages were more extended after the application of 1500 and 3000 than after 500 shock waves. No difference was seen between 1500 and 3000 shock waves.

The effect of shock waves on normal canine kidneys was examined in two groups of dogs whose right kidneys were exposed to 3000 shock waves generated with 20 kV and 40 nF in a Dornier HM II lithotripter. The groups differed only in the rate of shock wave administration which was 100 and 1 per second, respectively. Autopsy was performed 24 to 30 h later. Macroscopically and histologically, significantly more haemorrhages occurred in the kidney parenchyma if shock waves were administered at a rate of 100 waves per second. Haemorrhages were diffuse, the outer medulla was most heavily affected. The results show that kidney damage is dependent on the rate of shock wave administration. They argue against a direct shock wave effect and favor cavitation as the mechanism of shock wave damage although thermal effects cannot be excluded.

Using the indirect immunofluorescence technique, the basic kallikrein-trypsin inhibitor of bovine organs, Trasylol, could be localized in tissue mast cells of bovine lung, liver, pancreas and parotid gland. Identification of cells exhibiting specific fluorescence as tissue mast cells was achieved by combined light and electron microscopic diagnosis of bovine liver tissue sections. The presence of Trasylol in mast cells explains the widespread distribution of this inhibitor in functionally totally different organs or tissues of the bovine organism, as determined earlier by biochemical means. Identification of Trasylol as a mast cell constituent will facilitate the search for the biological function of this inhibitory protein in connection with a unique and highly specialized cell population.