An in-depth diagnostic exploration of an inflammation and necrosis syndrome in a population of newborn piglets.

Inflammation and loss of tail integrity can be reasons for serious impairment of animal welfare and one of the major challenges facing modern pig farming. Evidence from practice increasingly suggests that tail lesions might be caused not only by tail biting but also by inflammation and necrosis, which can occur without any action from other pigs. Such changes are not limited to the tail but can also be observed in the ears, heels and soles, claw coronary bands, teats, navel, vulva and face. To describe inflammatory and necrotic manifestations in newborn piglets, all 146 piglets from 11 sows were clinically examined not later than 2 h after birth. In addition, the tail base of 30 randomly selected piglets out of the 146 was histo-pathologically examined as one of the most conspicuously affected body parts. Over 80% of the newborns showed affections in the tail base, claw wall and heels. In 65-87% of the animals, the coronary bands, teats, the face and the ears were affected. None of the 146 piglets was completely free from pathological manifestations. On average, the piglets were affected in six out of nine body parts simultaneously. Histological examinations showed that clear alterations in the skin were already manifested around the time of birth in all examined piglets. Alterations were characterised by the occurrence of numerous lymphocytes and granulocytes throughout the entire subepithelial connective tissue, predominantly in perivascular and perifollicular localisation but also within directly subepithelial glandular ducts and diffusely within the subepithelial connective tissue. In the majority of individuals, the epithelial structure was intact. This concurrence of symptoms in the newborns indicates a primarily endogenous aetiology of an inflammation and necrosis syndrome. Further studies in diverse herd contexts are necessary to establish the conditions for the emergence of such a syndrome and develop welfare indicators.

Serotonin-containing cells in the gastrointestinal tract of newborn foals and adult horses.

Serotonin (5-hydroxytryptamine, 5-HT), a regulatory amine of mucosal enterochromaffin cells plays an important role in the control of gastrointestinal smooth muscle contraction and epithelial secretion. Serotonin has also been associated with gastric ulcers, diarrhoea and abdominal pain. In spite of the high incidence of these gastrointestinal disorders in newborn foals and adult horses, no data are available regarding 5-HT immunoreactive cells (i.c.) in the gastrointestinal tract (GIT) of foals, and for adult horses, data are incomplete and contradictory. In this study, the distribution and relative frequency of 5-HT i.c. in the GIT of newborn foals and adult horses were determined immunohistochemically. In foals as in adults, a relatively large number of 5-HT i.c. were detected in all portions of the GIT. In foals, a significantly higher amount of cells was found in the pyloric region and margo plicatus of the stomach, as well as in the caecum and colon ascendens compared with adults. Our results provided rationale for further research concerning the role of 5-HT i.c. during the milk diet or in the regulation of gastrointestinal growth/cell proliferation, and in the pathogenesis of gastric ulcers, especially in newborn foals.

Development of the glandular epithelium of the bovine parotid gland during ontogenesis.

The development of the parotid gland was examined in 36 bovine embryos and foetuses with a crown-rump-length (CRL) from 28 up to 1000 mm by light, transmission electron microscopical and actin-immunohistochemical methods. The anlage of the parotid gland in an embryo with 28 mm CRL can be found at the lateral angle of the primitive oral cavity as a local thickening of the epithelium. During the second month, the differentiation of primary ducts and endbuds starts and a lumen develops in the primary ducts. At the end of the second month a lumen appears in the terminal endbuds. In the immature endpiece cells first secretory granules can be seen from a CRL of 240 mm. In the third month differentiation between intra- and inter-lobular ducts is possible. Immature myoepithelial cells present as a basal layer of flattened cells between the epithelial cells and the basement membrane at the end of the second month. During further development they increase in number, become more flattened and form long cellular processes. At the end of the fourth month isolated actin filament bundles are formed, which were also detected by an antibody against smooth muscle actin. The actin filaments condense continuously until they fill the cell processes completely at the end of foetal development.

[The alimentary canal of the Siberian chipmunk (Eutamias sibiricus, Laxm. 1769): macroscopic and light microscopic examination]. / Der Rumpfdarm des Burunduk (Eutamias sibiricus, Laxm. 1769): makroskopische und lichtmikroskopische Untersuchungen

The canalis alimentarius of the Burunduk (Eutamias sibiricus), a rodent belonging to the family Sciuridae, were examined macroscopically (12 animals) and light microscopically (three animals). The esophagus is lined with a stratified non-keratinized squamous epithelium. The one-chambered stomach is of a simple type covered with a glandular mucous membrane. When empty and moderately filled, the stomach looks like a curved sack and lies intrathoracally. The filled stomach extends to the left and ventrally into the regio abdominis media. The greater omentum covers incompletely ventrally and in a part laterally the intestinal mass. The intestinal canal averages about 780 mm in length, that is 6.5 as long as the whole body. The relative length of the small intestine compared with the large intestine is 36-64%. The U-shaped Duodenum is composed of a Pars cranialis, descendens and ascendens and possesses a Plica duodenocolica as well as a Plica duodenocolica accessoria. The Jejunum averages about 420 mm length and is mainly located in the right and ventral part of the regio abdominis media. As in other rodents, the cecum is well developed. The length of the ascending colon averages about the body length and forms an Ansa proximalis and two parallel loops, Ansa media and Ansa distalis coli, both lying in the right Cavum abdominis. Peculiar for the colon are Noduli lymphatici solitarii surrounding cavities lined by a surface epithelium. According to the anatomical structure of the gut and based on physiological diet facts the Burunduk is not a mere herbivore but has to be classified as an omnivore depending upon uptake of animal food protein.

Proliferation in the gastric epithelium of bovine abomasum during foetal development as revealed by Ki-67 immunocytochemistry.

For the first time, proliferative cells in the abomasal mucosa of 30 bovine foetuses with a crown-rump length of 34 to 1000 mm (approximately 45-250 days of gestation) were detected using the antibody MIB-1 against the (human) nuclear-associated protein Ki-67. At the beginning of mucosal development, the epithelium is stratified and MIB-1 positive cells are scattered all over the epithelium. With the formation of gastric pit/gland invaginations, the proliferative cells are mostly confined to the basal half or third of the gastric pit/gland unit, both in the regio glandulae propriae and in the regio glandulae pyloricae. From the 27th week in the regio glandulae propriae and the 30th week in the pyloric gland region, respectively, the proliferative cells move upwards and are situated in the bottom of the pit and the upper part of the gland, whereas the base of the gland is free of labelling.

Light and electron microscopic investigation of the lectin-binding pattern in the oxyntic gland region of bovine abomasum.

For the first time the expression of glycoconjugate residues in the oxyntic gland region of bovine abomasum has been investigated by means of lectin histochemistry. For light microscopic investigations, a battery of ten lectins, Con A, PSA, UEA I, WGA, LEA, SNA, RCA120, MPA, DBA and SBA was used. For electron microscopic examinations, WGA and RCA120 were utilized. The staining pattern of the lectins in all exocrine cell types of the oxyntic gland region is described. Compared to the results of monogastric species our study reveals some similarities, but just as many differences in the composition of glycoconjugate residues in bovine exocrine cell types. Typical for surface mucous cells is the amount of L-fucose, N-acetyl glucosamine residues and Galbeta1, 4GlcNAc sequences in the secretory granules. SNA could serve as a marker for surface mucous cells, because this lectin exclusively stains the plasma membrane and the secretory granules of surface mucous cells and the extracellular mucus. L-fucose and N-acetyl glucosamine are typical for the secretory granules of mucous neck cells. In addition, the secretory granules show the highest amount of N-acetyl galactosamine residues of all exocrine cells, so that DBA and SBA are recommended as marker lectins for mucous neck cells. Most lectins strongly stain the intracellular membrane system of oxyntic cells. The cocktail of glycoconjugates in the vicinity of the HCI production site provide protection against chemical injury. In chief cells only the apical plasma membrane is more or less labeled with all lectins apart from SNA. Specific marker lectins for oxyntic cells or chief cells of the bovine have not been characterized.

[Structure of infrapatellar synovial ligament in dogs]. / Struktur des Ligamentum synoviale infrapatellare beim Hund.

The knee joint of the dog is frequently the subject of surgery if the cruciate ligaments or the menisci are injured. In the knee joint of the dog we find a ligament, which is spread out between the anterior part of the fossa intercondylaris ossis femoris and the corpus adiposus infrapatellaris. This ligamentum synoviale infrapatellare has not previously been described and represents a homologous structure to the plica synovialis infrapatellaris of human knee joint. Just like the latter and just like the cruciate ligaments it is a rudiment of a septum articulare genu, which is spread out between an articulatio femorotibialis and an articulatio femorofibularis in the early phylogenesis of tetrapods. The ligamentum synoviale infrapatellare of the dog consists of a stratum synoviale and a stratum spinosum, which includes blood vessels, nerves, many collagenous fibres and some elastic fibres. We do not find evidence for sensory nerve endings or corpuscular receptors. Therefore a servering of the ligament during knee joint surgery does not affect the proprioceptive potential of the knee joint.

Electron-microscopic detection of cytoskeletal actin in the epithelial cells of bovine abomasum.

The fine structural distribution of cytoskeletal actin was investigated in the oxyntic gland region and in the pyloric gland region of bovine abomasal mucosa using immunoelectron methods. In all exocrine cell types of the gastric epithelium, actin filaments exhibit a polarized pattern of distribution. In the members of the mucus- and protein-synthesizing cell line, the actin filaments form a prominent barrier to the exocytosis of secretory granules underneath the apical membrane. Therefore, actin is supposed to be involved in the control of exocytosis. The basolateral subplasmalemmal cortex of the exocrine cells, however, shows weaker labeling for actin filaments. In this position actin might be responsible for the movement of epithelial cells along the length of the gastric gland during physiological cell renewal and for the maintenance of the integrity of the epithelial unit and of cell polarization. In parietal cells of bovine abomasum, actin filaments are, in addition, associated with the intracellular canaliculus, but not with the tubulovesicular compartment. We assume that actin filaments reorganize the canalicular membrane after membrane translocations in the course of acid secretion. For the first time, actin filaments were documented in the rare brush cell type of bovine abomasum, where they do not form a terminal web beneath the apical membrane and therefore point out the nonexocrine function of the brush cell type. In all polarized cells of the bovine abomasum, actin filaments underlay the two apical members of the junctional complex, the tight junction and the adherens junction, where they might be involved in the regulation of cell adhesion, cell motility and cell shape determination.

Ultrastructure of the zymogenic-cell lineage in abomasal mucosa of adult cattle.

The ultrastructural differentiation and maturation of the neck cells and the zymogenic cells during physiological cell renewal were investigated in the abomasal oxyntic-gland region of cattle. Immature neck cells of the distal isthmus and proximal neck exhibit transitional morphology to the predominantly mucous isthmus cells. Neck cells confined to the glandular neck are characterized by bipartite peptic-cored mucous secretory granules. In a proximal-distal gradient along the neck, a progressive increase in the peptic granular component and concomitant reduction in mucous components paralleled by proliferation of the rough endoplasmic reticulum creates pre-zymogenic cells in the proximal glandular base. These, in turn, give rise to mature zymogenic cells with pure peptic secretory granules and typical zymogenic cell morphology. In the depth of the gland, older degenerative zymogenic cells are found. Variations in size and number of the zymogenic granules point to different secretory activities of the mature zymogenic-cell population of the glandular base. These results favour the conception of a zymogenic-cell lineage arising within the isthmus and passing through different developmental stages, including neck cells, during their migration down the gland.

[Intraepithelial nerve endings in the lingual marginal papillae of newborn piglets]. / Intraepitheliale Nervenendigungen in den Zungenrandpapillen neugeborener Ferkel.

The structure and occurrence of nerve fibres and nerve terminals in the lingual marginal papillae of newborn piglets are investigated by means of the osmium-zinc-iodate method and by transmission-electron microscopy. Subepithelial nerve fibres primarily accompany the blood vessels. They cross the epithelium with an almost vertical course to terminate in the stratum superficiale or the stratum corneum. Due to rows of varicosities, the axons look like a 'string of pearls'. As a result of the superficial localization and the typical ultrastructure, they seem to have a sensory function. Therefore, the papillae marginales are considered to function as mechanoreceptors.

[Age-dependent changes in the sub-epithelial blood supply to the bovine rumen]. / Altersabhängige Veränderungen an den subepithelialen Blutgefässen des Pansens vom Rind.

Qualitative age-related changes in the structure and the position of subepithelial blood vessels in the bovine atrium ruminis were investigated on the electron microscopical level in 39 fetal, peri- and postnatal individuals as well as in adult animals of different ages. Standardized morphometrical methods were applied and the data were statistically evaluated. The distance between epithelium and capillary endothelium, the endothelial fenestration and the thickness of the endothelial wall as well as the endothelial-epithelial exchange sectors facing each other were distinctly a function of age. Crucial changes of these parameters were either finished until the sixth postnatal month and were pronounced during the period of feeding adaptation from milk to roughage or were not markedly influenced during this period. The degree of endothelial vesiculation showed individual variations but was not a function of age or feeding regime.

[The differentiation of the surface mucous-cell line in the abomasum of the adult cow]. / Die Differenzierung der Oberflächenzellinie im Labmagen adulter Rinder.

The differentiation of the surface mucous-cell lineage during physiological cell renewal was investigated using light and electron microscopy in the abomasal mucosa of adult cattle. The surface mucous cells constitute a morphologically and functionally heterogeneous population, whose members correspond to different developmental stages, OFFanged in a distoproximal gradient from the depth of the pit towards the free luminal surface. The cell lineage comprises immature pre-pit cells near the proliferative isthmus, mature pit cells within the foveola, and older interfoveolar cells lining the free surface. Ultrastructurally, differentiation can be traced towards a predominantly mucus-producing cell type and finally towards a surface-protective cell variant, which degenerates in situ and is extruded into the lumen without affecting epithelial integrity.

Cytoarchitecture of the bovine pyloric epithelium during early ontogenesis.

The cytoarchitecture of the pyloric gland region in the early ontogeny of the bovine abomasal mucosa was investigated using light and transmission electron microscopic methods. Two cell types are involved in forming the lamina epithelialis in the youngest fetus with a 24 mm crown-rump-length (CRL): the indifferent cell and the endocrine cell. With a CRL of 71 mm, two other cell types occur, the granule-containing cell and the brush cell. The indifferent cell represents the first stem cell, which develops into the secretory granule-containing cell type. This seems to be the secondary stem cell lining the top of the epithelium as well as the base of the primitive epithelial tubes, and it differentiates into the surface mucous cell and the pylorocyte. Endocrine cells appear as open and closed types and represent the most differentiated cells already present in the youngest specimen in this investigation. The most rare cell type, the brush cell, appears in the bovine abomasal ontogeny much earlier than in other mammalian species.

[Morphology of the marginal lingual papillae in newborn piglets]. / Zur Morphologie der Zungenrandpapillen neugeborener Ferkel.

The morphology of the marginal lingual papillae in eight newborn pigs aged 1-5 days was examined at the light-microscopical level, as well as, for the first time, using electron transmission and scanning methods. The papillae marginales are arranged tuft-like or rosetted with chief and accessory papillae, the individual papillae varying considerably in shape. Leaf-, tongue- or fingerlike and conical shapes predominate. The stratified squamous epithelium is either keratinized, resembling the epidermal differentiation pathway, or non-keratinized, according to the mucosal pathway. The characteristic morphology of keratinocyte differentiation is shown with special reference to the establishment of the permeability barrier. The connective tissue papillae are intensively surface-enlarged by means of multiple fingerlike protrusions.

Heterogeneity and migration-related zonation of K(+)-ATPase activities in the oxyntic cell lineage of adult cattle.

Activities of the H+, K(+)-ATPase and the Na+, K+, ATPase have been localized in the morphologically heterogeneous oxyntic cell lineage of adult bovine abomasal mucosa, by means of K(+)-dependent paranitrophenylphosphatase (K(+)-pNPPase) histochemistry. At the light- and electron-microscopic level, only members of the mature oxyntic cell population within the oxyntic glandular base exhibit strong enzyme activity. Superficial oxyntic cells of the proximal isthmus and deep pit, arising from the upward migration of precursor cells and commonly supposed to have a high capacity of secreting acid, show weak or no enzyme activity. This is also true of the immature and pre-oxyntic cells of the generative zone. Global enzyme activity varies among the mature glandular oxyntic cell population. Ultracytochemically, strong H+, K(+)-ATPase (ouabain-insensitive K(+)-pNPPase) activity is associated with the apical plasmalemmal and expanded canalicular membrane in contrast to Na+, K(+)-ATPase (ouabain-sensitive K(+)-pNPPase) activity, which is localized on the basolateral plasmalemmal folds. In both cases, histochemical deposition is confined to the cytoplasmic aspect of the membranes. These results suggest a functional zonation and position-dependent heterogeneity of the oxyntic cell lineage related to the bidirectional mode of migration of pre-oxyntic cells during physiological cell renewal. Functional heterogeneity within the mature glandular oxyntic cell population is in accordance with the continuous mode of gastric acid secretion in cattle.

[Architecture and fine structure of the terminal blood vessels in the marginal papillae of the tongue in newborn piglets]. / Architektur und Feinstruktur der terminalen Blutgefässe der Zungenrandpapillen neugeborener Ferkel

The vascular architecture of the marginal papillae of the tongue was examined in one to five day old piglets by means of light and transmission electron microscopy and scanning microscopy of vascular corrosion casts. The marginal papillae of the tongue exhibit a "rope ladder-like" principle of blood supply. Every papilla contains one ascending arteriole, which branches into single capillary loops each supplying a protrusion of the multiply branched base of the capillary body. The transition of the arteriole takes place on the tip of the papilla. Subsequently the capillary loops converge onto this venule. Precapillary sphincters are observed at the origin of the capillary loops. This type of vessel arrangement offers the opportunity to use the capillary system at maximum efficiency, thus allowing an erection of the papillae marginales during the process of suckling.

[The spermathecal epithelium of the queen bee (Apis mellifera): morphology, age-dependent changes and cell contacts]. / Das Spermathekalepithel der Bienenkönigin (Apis mellifera): Morphologie, altersabhängige Veränderungen und Zellkontakte.

The spermatheca of the honey bee queen is covered by a single-layered, uniform, polarised epithelium. The apical cell surface is greatly enlarged by protrusions and plasma membrane infoldings, the basal cell surface by numerous interdigitating, long, small processes. Cytoplasmic organelles are chiefly represented by mitochondria. Numerous microtubuli extend throughout the cytoplasm. Golgi and endoplasmic profiles are rare. The cells are subject to senile degeneration: with increasing age, a variety of cytoplasmic inclusions appear, among which are myelinated membranes, dense bodies and dense filamentous aggregates. The spermathecal epithelium does not seem to be involved in exocrine secretion related to nutrition of the long-term stored spermatozoa. The ultra-structure points, however, to ion transport functions and to an engagement in the maintenance of an adequate physicochemical environment ensuring the viability of the spermatozoa. Cellular junctions are represented by luminal zonulae adherentes, focal cell-cell adhering junctions and hemiadhering junctions along the basal plasmalemma. Desmosomal contacts and cytoskeletal intermediate filaments are missing. Along the lateral plasmalemma, gap junctions and septate junctions are found.

Oxyntic cell differentiation during physiological cell renewal in abomasal mucosa of adult cattle.

The origin and differentiation of the oxyntic cell lineage during physiological cell renewal was investigated by light and electron microscopy in the abomasal mucosa of adult cattle. The morphologically heterogeneous oxyntic cell population exhibits various developmental subtypes depending on the position within the oxyntic unit. Pre-oxyntic cells of the isthmus and neck represent the immature precursors. Though heterogeneous with respect to the degree of canalicular and tubulovesicular membrane development, they all contain secretory granules resembling those of either isthmus cells, immature surface mucous cells, neck cells or young chief cells. A secretory granule-free stem cell is not present in the bovine. Downward to the gland base genesis of canalicular as well as tubulovesicular membranes is gradually completed; thus pre-oxyntic cells give rise to mature oxyntic cells. Older degenerative oxyntic cells, primarily located within the gland bottom, are characterized by progressive involution of canalicular and tubulovesicular membranes. Towards the pit, differentiation of pre-oxyntic cells is associated with atypical and incomplete development of canaliculi and tubulovesicles. In consequence, these superficial oxyntic cells have a reduced secretory capacity from a morphological point of view.

[Fine structure of the trigeminal nerve nucleus of the domestic fowl]. / Feinstruktur der Trigeminuskerne vom Haushuhn.

The trigeminal nerve nuclei are examined light- and electron-microscopically in the adult domestic fowl. The nucleus sensibilis principalis nervi trigemini is formed by scarce, medium-sized, round-to-ovoid polygonal neurons. The Nissl bodies are concentrated around the nucleus and consist of short cisterns of the rough endoplasmic reticulum densely bordered with ribosomes. The nucleus tractus spinalis nervi trigemini extends to the first segments of the cervical cord. The rostral part of the nucleus is characterized by medium-sized polygonal neurons. Their cell bodies are densely packed with coarse Nissl bodies. Small multiforme cell types with large nuclei frequently showing two nucleoli predominate in the caudal part. The motorical main portion, nucleus motorius nervi trigemini consists of medium-sized as well as great polygonal neurons. The accessory portion, nucleus motorius dorsalis nervi trigemini, consists of medium-sized polygonal neurons. Both nuclei show the typical motoneuron cytomorphology. In the neuropil, the axodendritic synapses can be differentiated into five types. Occasionally, densely packed glial lamellae and giant mitochondria occur.

Differentiation of oxyntic cells during early ontogenesis in the bovine.

The origin and the differentiation of oxyntic cells in fetal bovine abomasum were investigated using transmission electron and light microscopic methods. In the oxyntic gland region oxyntic cell precursors and immature oxyntic cells appear as early as at the end of the first trimester of gestation--much earlier than described in any other mammalian animal species. Immature oxyntic cells are characterized by long apical microvilli, by their triangular-shaped light cytoplasm rich in large and numerous mitochondria, by the existence of vesicular profiles and by the incipient invagination of the apical plasma membrane forming a primitive intracellular canaliculus expanding into central areas of the cell. The oxyntic cell represents the first exocrine cell type developing from secretory granule-containing cells in the base of the primitive gastric glands.