bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development and Fine Structure of the Reticulate Scales of the Turkey Foetuses with Regard to Occurrence of the Food Pad Lesions in Turkey Poults
Authors: Breuer P. , Buda S. , Budras K. D. 
Published: November 2005

Introduction:  Most of the morphological studies on the skin of birds refer to chickens. Little can be found about the specific fine structure of the foot‐pad epidermis of turkeys and almost nothing is known about the developing reticulate scales in turkey foetuses. This study deals with the question as to whether the development and morphology of the reticulate scales of turkeys are similar to those of chickens. Since the first signs of food‐pad dermatitis can be observed in turkey poults at the age of four days, it was additionally examined if these alterations can be found in turkey foetuses already.Methods:  Foot pad samples of heavy strain BUT Big 6 turkeys were collected at different developmental stages (day 20, 23, and 28 of incubation). The specimens were compared by light‐ and electron‐microscopic methods.Results:  On the 20th day of incubation, the reticulate scales cover the food pads as small knob‐like structures. Between the embryonic epidermal cells wide inter‐cellular spaces are visible, and in the intermediate cells multigranular bodies (MGBs) are detectable. Peridermal cells cover the reticulate scales. They are characterized by peridermal granules and protuberances of the outer cell membrane. On the 23rd day of incubation, many lipid droplets are scattered within the intermediate cells. Because a thin stratum corneum has formed, the periderm is almost completely sloughing off. On the 28th day of incubation, the turkey poults hatch. The epidermis has almost reached maturity and a broad stratum corneum is detectable.Conclusions:  The development and morphology of the reticulate scale epidermis of turkey is comparable to that of chicken, although little differences were found. Besides former investigations, which described the peridermal protuberances as microvilli, scanning‐electron microscopy proved that they also show a fingerprint‐like surface structure that has not been observed for birds previously. Up to the hatching day, no signs of food pad alterations are seen in developing turkeys.
Innervation Pattern of Dermal Blood Vessels in the Bovine Claw Shows Functional Adaptation in Different Areas
Authors: Buda S. , Budras K. D. 
Published: November 2005

Introduction:  The blood circulation in the claw plays an important role in the pathogenesis of claw diseases. The blood vessel diameter is regulated by innervation with different nerve fibre qualities. In case of inflammation or unphysiologically high mechanical load, the delicate balance of vasodilative and vasoconstrictive neurotransmitters seems to be disturbed and may aggravate the alterations. Knowledge about the innervation pattern of the dermal blood vessels could therefore help to understand some aspects in the pathogenesis of claw diseases.Material and Methods:  The lateral claws of the hind limb of cows from a local abattoir were examined. Tissue samples were taken from different segments of the claw, fixed and processed for immunohistochemistry. Antibodies against protein gene product 9.5, tyrosine‐hydroxylase, choline acetyltransferase, substance P and calcitonin gene‐related peptide were applied and colocalization studies were carried out. Results were evaluated with a confocal laser scanning microscope.Results:  Dermal blood vessels in the claw are surrounded by nerve fibres containing different neurotransmitters. Occurrence and density differ depending on the respective segment. In the bulbar segment, more vasodilative fibres are demonstrable while in the solear segment vasoconstrictive nerve fibres prevail. The highest innervation was found in all segments around specialized sphincteric arteries in the dermis just beneath the dermal surface modification.Conclusion:  The innervation pattern in the claw depends on segment‐specific functional demands. The fine‐tuning of the blood flow in the dermal vascular system is mediated by a combination of different nerve fibres that emit vasoactive substances.Acknowledgement:  This work was supported by the European Communities under the Lame cow project QLK5‐CT‐2002‐00969.The authors are solely responsible and the work does not necessarily represent the opinion of the European Communities.
Anatomical Location and Histology of the Tonsilla Paraepiglottica in Sheep
Authors: Cocquyt G. , Simoens P. , Van den Broeck W. 
Published: November 2005

The location, size and histological structure of the ovine paraepiglottic tonsils were determined in 20 sheep. Macroscopic examination of the pharyngeal tonsils was performed in 10 sheep of 9 months of age, of which the heads were fixed in acetic acid 2% for 24 h, and in non‐fixed heads of five sheep aged between 6 and 9 months. The paraepiglottic tonsil is located lateral to the epiglottis in the ventromedial segment of the pharyngeal sidewall, i. e. at the floor of the piriform recess. The tonsil appears as a cluster of small nodular elevations, which are white after fixation in acetic acid and are called hereafter tonsillar nodules. The number of these nodules per tonsil ranged from 1 through 8. The length of the tonsil varied from 5 till 14 mm, and the width ranged from 2 till 5 mm. The tonsils of 5 sheep aged between 6 and 9 months and of five sheep aged between 9 and 12 months were excised and fixed in 3.5% formaldehyde. The blocks were processed routinely for histology and embedded in paraffin wax. Serial sections (8 μm thick) were stained with eosin and haematoxylin. Histology revealed that each tonsillar nodule consisted of several lymphoid follicles (noduli lymphatici) surrounded by parafollicular tissue. Most lymphoid follicles were secondary follicles consisting of a germinal centre, a dark zone and a mantle zone. Primary follicles devoid of germinal centres were most obvious at the periphery of the tonsillar nodules. The stratified squamous pharyngeal epithelium covering the lymphoid tissue was frequently infiltrated by numerous lymphocytes, forming a follicle‐associated epithelium. Crypts were absent, but in some cases the pharyngeal epithelium was slightly infolded into the lymphoid tissue. The tonsillar nodules were almost completely encapsulated by dense connective tissue from which septa extended into the larger nodules.Acknowledgement:  This study was supported by BOF Grant of Ghent University Project #011B4101).
Anatomical Basis of Physiotherapeutic Treatment of Lumbar Spinal Nerve Disorders
Authors: Grünenfelder F. I. , Steffen F. , Mouwen M. A. , Boos A. 
Published: November 2005

In contrast to human medicine, the significance of appropriate post‐operative care in companion animals is often neglected or even unknown. Physiotherapeutic exercises, also called physical therapies, are the golden standard of rehabilitation in human orthopaedics. In dogs and cats, such supportive therapies following surgery are rarely performed. Presently, physical therapeutic exercises, which are well established in man, are transferred to companion animals. However, there is no generally accepted scheme of procedures adequate to cats and dogs. Furthermore there is no study dealing with the exact effects of the various exercises performed with these species. Due to this paucity of information, the effect of several physical exercises concerning the lumbar spinal nerve roots transferred from man to the dog were assessed macroscopically. In ten euthanized healthy beagles up to eight years of age, the lumbar spine was surgically separated from adhering dorsal muscles. The lumbar nerve roots were visualized by removing the connective tissues surrounding the foramen intervertebrale. Nerve roots, i.e. spinal ganglia, were marked immediately outside the vertebral column applying a dot of yellow paint while the cadaver was in lateral recumbency. In man, for maximal sciatic nerve root movement the straight leg raising (SLR) (Maitland, 1986) exercise is applied on the patient lying on the back. For nervus femoralis movement the passive knee bending exercise is performed. In the dog, however, performing only the transferred SLR has a poor effect on L7. It can greatly be enhanced by a supplemental inward rotation of the hip joint by fixing the stifle joint and moving the lower leg medially. Concerning L4‐L6 nerve roots, the hip joint is maximally extended and the effect can be improved by an outward rotation of the leg. The results of the present study indicate that the simple transfer of physical exercises from man to companion animals does not result in identical results in the latter species. Modifications considering different anatomical conditions should be kept in mind if clinical results are poor.Reference  Maitland, G.D., 1986: Vertebral Manipulation, 5th edition, Butterworth–Heinemann, London
New Concepts for the Functional Maturation of the Bovine Claw: Endothelial Biology, Angiogenesis and Ageing
Authors: Hirschberg R. M. , Müller K. , Plendl J. 
Published: November 2005

Introduction:  Endothelial dysfunction and impaired angiogenesis are connected to ageing. However, the mechanisms involved in age‐related alterations are not fully elucidated, whereby reduced VEGF‐expression and decreased mobilization of circulating endothelial progenitor cells are suggested as possible causes. When cultured in vitro, endothelial cells often enter a growth arrest phase called ‘cellular senescence’ that is consistent with many changes in age‐related vascular disease. Based on the decreasing lifespan observed in high yielding dairy cows, a hypothesis has been formulated that these cows, due to their enormous metabolic performance, show an accelerated process of ageing, resulting in typical production‐related diseases, particularly lameness. As a basis for further research into the role of endothelial cell biology in high producing cattle, the aim of this study was to set up a model of endothelial ageing. As a first step, the role of angiogenesis in the functional adaptation of the microvasculature of the bovine pododerma was examined.Material and methods:  Scanning electron microscopy of vascular corrosion casts of healthy juvenile and adult claws as well as pathologically altered claws, and routine light microscopy of pododermal serial sections was compared to an in vitro model of angiogenesis based on cultured bovine microvascular endothelial cells. For detection of angiogenic molecular control mechanisms effective in both, the pododermal system and our cell culture model, lectin‐ and immunohistochemistry as well as RT‐PCR were carried out.Results and discussion:  In the adolescent and adult claw, sprouting and intussusceptive angioadaptation was demonstrated. Evidence of angiogenic processes was also detected in the pathologically altered claws. Immunolocalization of angiogenic factors within the dermo‐epidermal system of the claw was established. The detected angioadaptation may be visible expression of the increased metabolic demands of the claw caused by the growing body‐weight‐load. Increase of the pododermal vascular density via angiogenesis was also the connectional reparative principle in pathologically altered claws.
Angiogenesis and Vascular Regression in the Corpus Luteum Periodicum
Authors: Hünigen H. , Bisplinghoff P. , Plendl J. 
Published: November 2005

Introduction and Aim:  The corpus luteum is one of the most intensely vascularized tissues. Luteal angiogenesis is strictly controlled and blood vessels regress completely within a short period of time. The aim of this study was to investigate vascular dynamics in relation to cellular and molecular mechanisms of luteal angiogenesis and anti‐angiogenesis.Material and Methods:  Endothelial cells of blood vessels in paraffin sections of bovine corpora lutea from different stages were examined by labelling with the lectin Bandeiraea simplicifolia agglutinin I. Angiogenesis was studied by morphometry of the capillaries, and immunolocalization of the angiogenic factor VEGF and VEGF‐receptor 2. Presence of apoptotic luteal and endothelial cells was investigated using the TUNEL test and transmission electron microscopy.Results:  During development of the corpus luteum (day 3–8 of the oestrous cycle) a dense capillary network (8–12% area ratio) is established and maintained until day 17. Early regression (day 18–24) is characterized by a remarkable decrease of capillaries (1% area ratio). In the regressing corpus luteum the number of apoptotic luteal cells is closely correlated (r = 0.9) to the number of apoptotic endothelial cells. VEGF is immunolocalized in luteal cells (day 3–17), smooth muscle cells and endothelial cells of arterioles of the regressing corpus luteum. During late luteal regression, a moderate increase of capillaries (2.5% area ratio) is obvious.Conclusions:  The dynamic changes of the capillarity during development and regression of the cyclic corpus luteum correlate with VEGF and VEGF‐R2 activities. In contrary to expectations the late stage of luteal regression is accompanied by angiogenesis. One reason for this phenomenon may be an increase in metabolic activity resulting in re‐organization of blood vessels already regressed.
Angiogenesis and Interstitial Pressure in a Rat Tumour Model
Authors: Hünigen H. , Drees R. , Schnorr J. , Plendl J. 
Published: November 2005

Introduction and Aim:  Angiogenesis, the formation of new blood vessels, is a crucial process in physiological and pathological growth. Pathological angiogenesis is responsible for growth and metastasis of solid tumours, and, when blocked, improves prognosis. As a result of the angiogenic cascade in solid tumours an irregular, leaky capillary network develops. The aim of the present study was to define malignant tumours’ vascular characteristics and reveal functional anatomy by quantification of the microvasculature and interstitial pressure (IP) in relation to tumour fluid dynamics as visualized by contrast enhanced magnetic resonance imaging (MRI).Material and Methods:  Dynamic MRI and measurement of the IP was performed in 21 rats implanted with colon carcinomas subcutaneously. Angiogenesis was studied by morphometry of the capillaries, and immunolocalization of the angiogenic factor VEGF and VEGF‐Receptor 2.Results and Conclusions:  Histology, immunohistochemistry and MRI confirmed concentric arrangement of 4 tumour zones. The tumour margin included loose connective tissue with abundant mononuclear cells. Many large microvessels were seen in this most intensely vascularized zone. IP measurement in this zone was adjusted to the zero level. Diameter of the peripheral zone of vital cells measured 1.3 mm. Capillaries were smaller and sparse. Dynamic MRI revealed peripheral washout of the contrast agent in this zone. After an initial increase of the signal intensity a hypo‐intense rim was formed within a few minutes. The intermediate region was characterized by islands of vital tumour cells containing 3% capillaries (hot spots). The innermost area, the necrotic zone, took 35% of the total tumour area with less than 0.5% vessels. The IP increased from the periphery to the centre. VEGF and VEGF‐receptor 2 was found in the vessels of the tumour margin and vital tumour cells of the peripheral zone. From this can be concluded that the peripheral washout phenomenon seems to be correlated with elevated interstitial pressure and increased capillary density and therefore may be a reliable sign of malignancy.
Leishmaniasis in Canis familiaris – a Report About Microvascular and Cellular Architecture of the Infected Spleen
Authors: Alexandre‐Pires G. , Gilot T. , Pais D. , Correia M. , Esperança Pina J. A. 
Published: November 2005

Leishmaniases are a globally widespread group of parasitic diseases from the group of anthropozoonoses. They are caused by an intracellular protozoan parasite that causes a wide spectrum of diseases in humans and dogs worldwide. In fact, the dog is considered one of the most important reservoir. The spleen is one of the several haematopoietic and immunocompetent organs involved. As this organ is a blood filter, the authors looked for the expression of this infection over the microvascular environment and modifications of the spleen cell population related to immunological responses to this parasitic condition.Tools:  Scanning electronic microscopy over intact tissue and corrosion casts, transmission electronic microscopy, histology and immunohistochemistry (MAC 387 and CD3).Results:  Our results show three important modifications concerning the microvascular architecture of the spleen when compared to the normal pattern. A striking scarcity of the sinusoidal system sheath that surrounds the central arteries of the white pulp, a huge development of pulp venules and veins, differentiation of typical features of high endothelial venular cells.Remarks:  According to our results it seems that independent of the virulence of the parasite involved and the kind of immunity prevalent in a particular host, the spleen develops blood dynamic conditions that allows a sluggish blood flow so that cells involved in immunological processes can proliferate and differentiate and it also contributes to the trapping of lymphocytes to the area through the differentiation of typical characteristics of HEV endothelial cells.
Vasculogenesis by Endothelial Progenitor Cells In Vitro
Authors: Käßmeyer S. , Plendl J. 
Published: November 2005

Introduction and Aim:  Vasculogenesis is the de novo formation of blood vessels from embryonic precursor cells. The formation of additional vessels is called angiogenesis, the sprouting from pre‐existing vessels by migration, proliferation and differentiation of endothelial cells. Until recently vasculogenesis was considered to be restricted to embryogenesis, however, evidence suggests that progenitor cells exist in the adult, able to participate in neovascularization. In order to study cellular and molecular control mechanisms without animal testing we have established in featuring the three‐dimensional formation of capillary‐like structures from microvascular endothelial cells. The aim of this study was to identify the specific subpopulation of cells that triggers the primary process of vasculogenesis in vitro.Material and Methods:  Endothelial cells were isolated from the bovine corpus luteum and examined by phase contrast and transmission electron microscopy. Immunolabelling was done for the most important pro‐angiogenic factor (VEGF) and its endothelium‐specific receptors (VEGF‐R1, ‐R2) as well as for endothelial cell surface markers (CD 31, CD51/61, CD29) and presumptive stem cell marker CD 34. Additionally VEGF and VEGF‐R1, ‐R2 expression was demonstrated by polymerase chain reaction (RT‐PCR).Results:  The beginning of vessel formation in vitro was initiated by confluence of endothelial cells. A linear and circular side‐by‐side arrangement of cells and the formation of capillary‐like structures with an internal lumen could be observed. Specific clusters of cells were identified. These cells were arranged in a star‐like formation, i.e., one particular round cell in the centre surrounded by several cells with extensions. Immunolocalization of VEGF, VEGF‐R1, ‐R2, CD 31, CD51/61, CD29 and CD34 was positive. VEGF‐R2 and CD 34 were found to be co‐localized in specific cells exclusively.Conclusions:  Results for the first time reveal the specific subpopulation of endothelial cells that trigger the start of vasculogenesis in vitro. These progenitor cells are characterized by a specific morphology, by the presence of endothelial cell markers and by the expression of stem cell marker in vitro models
Regulation of Cumulus Cell Numbers in the Course of the Canine Estrous Cycle
Authors: Kölle S. , Woehl‐Wenigerkind A. , Sinowatz F. , Braun J. 
Published: November 2005

In the canine, success rates of assisted reproduction techniques are very low. Since cumulus cells are known to play an essential role during the in vitro maturation (IVM) of oocytes, the aim of this study was to investigate the regulation of cumulus cell numbers in the course of the canine estrous cycle. Eighty‐two cumulus‐oocyte‐complexes (COCs) were obtained from 16 bitches undergoing elective ovariectomy during proestrus, estrus, metestrus and anestrus. First, mean cumulus cell numbers during the different stages of the cycle were compared. Then the incidence of programmed cell death (apoptosis) was detected by terminal deoxynucleotidyl transferase mediated dUTP labelling (TUNEL). Scanning electron microscopy (SEM) was used to confirm the presence of apoptotic cumulus cells. Additionally, mitosis was detected by using antibodies directed against the nuclear cell proliferation‐associated antigen Ki‐67. The mean number of cumulus cells in the COCs increased from proestrus to estrus (168.2 ± 9.2 to 265.5 ± 32.7, P < 0.01) and decreased from estrus to metestrus (265.5 ± 32.7 to 139.1 ± 10.7, P < 0.01) till anestrus (150.0 ± 8.3, P < 0.01). The percentage of apoptotic cumulus cells was generally very low during proestrus and oestrus (3.3% and 12.6%, P < 0.01) and distinctly increased during metestrus (83.1 %, P < 0.001). The predominance of apoptosis in the cumulus cells during metestrus was confirmed by SEM, which showed a high number of cells revealing cell shrinkage, loss of membrane integrity and cell disruption. Mitosis was highest during proestrus (2.7%) and oestrus (2.6 %) and decreased in the course of metestrus (1.8%) and anestrus (0.2%, P < 0.05).Our results imply that the distinct increase of cumulus cell numbers during proestrus and oestrus is due to increased mitosis and reduced apoptosis. The distinct reduction of cumulus cells during metestrus is predominantly regulated by apoptosis.
Incompleteness of the Structure of Liver Veins and Tissue Components in Neonatal Animals
Authors: Krishtoforova B. V. , Lemeschenko V. V. 
Published: November 2005

Introduction:  The formation of the liver structure at mammal embryogenesis is interconnected by drawing up of venous mains. In parallel to the transformation of the main veins, there is a reduction of the blood formation function and the liver transformation from the primary organ of embryogenesis into the secondary one, but the exception is immaturity and underdeveloped maturity mammals (Smirnova, 1967; Mechtiev, 1968; Bresler, 1993). The purpose of research is to establish morphofunctional criteria of the incompleteness in the blood vessels and in tissue components of the liver in neonatal animals.Material and Methods:  The afferent and efferent liver veins of calves, piglets and puppies at one day of age were investigated. The complex of morphological, roentgenological, ultrasound and statistic methods was used.Results:  It was established that the liver veins in newborn animals portoumbilical (afferent) and caval (efferent) collectors. In 1‐day‐old calves, the afferent collector is connected with caval way of the large vein flow of the main type. Relative weight of the liver in the calves is 2.31–2.85%, hepatocytes form balks and they are not always oriented radially to the central venuels. There are no seats of haemopoesis. Sonography of the liver and its veins proves inconstancy of the sizes depending on acts of breath. In 1‐day‐old piglets, many treelike anastomoses follow with the left hepatic vein. Relative weight of the liver in the piglets is 2.27–4.64%. The parenchyma of the organ is spongy with the seats of haemopoesis (0.04 3.61%). In 1‐day‐old puppies afferent and efferent collectors combine through the venous duct. Additionally, in the abdominal cavity of puppies, there are the vitelline artery (starts from a. mesenterica) and vein (runs to v. porta near the afferent collector), following to the umbilical ring. Relative weight of the liver in the puppies is about 5.18–6.04%. Hepatocytes form the chaotic congestion with haemopoetic points (2.04–7.14%).Conclusion:  Thus, incompleteness of morphology of the liver is shown in preservation of provisional vein structures and tissue components of the embryonic type, which is one of the factors complicating diseases of digestive organs in neonatal animals.