Histology of the venom gland of the puff-adder (Bitis arietans)

The histology of the venom gland of the puff-adder (Bitis arietans) has been investigated in the resting and stimulated state. No accessory venom gland was found to be associated with the main venom gland or duct in the same position as has been reported for other snakes. In the resting state the parenchyma of the venom gland was found to consist of tubules lined by a single layer of tall columnar secretory cells. After being stimulated to secrete by repeated milkings, the histological appearance of the gland changed and the epithelium was found to be more foliaceous and the component cells to be taller and more slender. A pronounced increase of pigment was also observed in the connective tissue septae. Micro-organisms were observed in the secretion pools of resting glands and by culturing the venom it could be shown that these were Staphylococcus aureus, Staphylococcus epidermidis and Klebsiella ozaenae. The presence of these organisms would suggest that the venom is not cytotoxic to all cells at this level of production.     

Comparative functional anatomy of hindlimb muscles and bones with reference to aquatic adaptation of the sea otter

Although the sea otter (Enhydra lutris) is a complete aquatic species, spending its entire life in the ocean, it has been considered morphologically to be a semi-aquatic animal. This study aimed to clarify the unique hindlimb morphology and functional adaptations of E. lutris in comparison to other Mustelidae species. We compared muscle mass and bone measurements of five Mustelidae species: the sea otter, Eurasian river otter (Lutra lutra), American mink (Neovison vison), Japanese weasel (Mustela itatsi) and Siberian weasel (M. sibirica). In comparison with the other 4 species, E. lutris possessed significantly larger gluteus, popliteus and peroneus muscles, but smaller adductor and ischiopubic muscles. The popliteus muscle may act as a medial rotator of the crus, and the peroneus muscle may act as an abductor of the fifth toe and/or the pronator of the foot. The bundles of the gluteus superficialis muscle of E. lutris were fused with those of the tensor fasciae latae muscle and gluteofemoralis muscles, and they may play a role in femur abduction. These results suggest that E. lutris uses the abducted femur, medially rotated crus, eversion of the ankle and abducted fifth digit or extended interdigital web as a powerful propulsion generator. Therefore, we conclude that E. lutris is a complete aquatic animal, possessing differences in the proportions of the hindlimb muscles compared with those in other semi-aquatic and terrestrial mustelids.     

Histological Structure of the Adrenal Gland of the Bottlenose Dolphin (Tursiops truncatus) and the Striped Dolphin (Stenella coeruleoalba) from the Adriatic Sea

The structure of the adrenal gland was studied in 11 bottlenose dolphins ( Tursiops truncatus ), and five striped dolphins ( Stenella coeruleoalba ). These species are legally protected in Croatia. All examined animals died of natural causes and were found stranded along eastern Adriatic coast. In both species the adrenal gland consists of a cortex and a medulla; the cortex is divided into three zones. Whereas in the bottlenose dolphin, there is a zona arcuata which contains columnar cells arranged in the form of arches; in the striped dolphin this zone is replaced by zona glomerulosa containing rounded clusters of polygonal cells. In both species, the zona fasciculata consists of radially oriented cords of polygonal cells, whereas in zona reticularis cells are arranged in branching and anastomosing cords. The adrenal medulla in both species contains dark, epinephrine-secreting cells and light norepinephrine-secreting cells. Epinephrine-secreting cells are localized in the outer part of the medulla, whereas norepinephrine-secreting cells are found in the inner part, arranged in clusters and surrounded by septa of thin connective tissue. The gland is surrounded by a thick connective-tissue capsule, from where thick trabeculae extend towards the interior. In the bottlenose dolphin, group of cells resembling both medullar and cortical cells can be seen within the capsule; whereas only groups of cells resembling cortical cells are found within the capsule of the striped dolphin. In the bottlenose dolphin invagination of the adrenal cortex into the medulla is obvious as well as medullary protrusions extending through cortex to the connective tissue capsule.     

Die laterokranialen Faszienstrukturen am Ober- und Unterarm sowie Unterschiede im Ansatz des M. biceps brachii bei Haussäugetieren

Structures of the laterocranial Fascia in the Upper- and Forearms of Domestic Mammals, including Differences in the Aponeuroses of the M. biceps brachii The laterocranial fascia of the upper arm and forearm, as well as aponeurotic relationships of the Musculus biceps brachii were investigated on each of ten forelimbs from horses, cattle and swine. Ten canine biceps were also investigated. Equine and bovine fascia contain elastic components. An as-yet undescribed ligament-like aponeuroses of the laterocranial forearm fascia to the Fossa radialis humeri was seen in all three species studied. The laterocraniale fascia of the upper and forearm form a common passage for the Musculi hrachialis et extensor carpi radialis. In the case of the horse, the ulnar aponeurotic tendon of the biceps muscle crosses below the Ligamentum collaterale cubiti medialis. In cattle, on the other hand, it runs between the two branches of the collateral ligament, to attach on the olecranon. This portion of the equine tendon protrudes into the joint. It has connective tissue character in young animals, but becomes fibrocartilaginous in older horses. The radial aponeuroses of the canine biceps exhibits two branches. A situation similar to that seen for the ulnar aponeuroses of the equine Musculus biceps brachii is observed on the inside surface of the porcine Ligamentum cubiti mediate, in which a wedge of connective tissue protrudes into the joint, taking on fibrocartilaginous character in older animals.     

Common tiger snake envenomation in dogs and mice—relationship between the amount of venom injected and the onset of clinical signs

SUMMARY Common tiger snake (Notechis scutatus) venom was injected into mice and dogs at various dose rates calculated on the known lethal dose (LD) for each species. The larger the dose of venom, the earlier was the onset of clinical signs and the more rapid and severe the course of the disease in both species. In dogs injected with 32 LD of venom, there was sudden collapse and death in about one hour from the time of injection without recovery from premonitory depression and before mydriasis occurred. Dogs given 5 to 16 LD of venom developed preparalytic signs (vomition, salivation or defaecation) in 5 to 30 min, mydriasis in 2 to 4h, became paralysed and died in about 2.5 to 5 h. When doses of venom of about 1 LD were injected, vomition and salivation occurred within 2 h and mydriasis in about 4 h. The dogs were unable to close the mouth completely despite retention of jaw muscle tone. At the site of injection of venom there was occasional but slight erythema and oedema. Sublethally envenomed dogs did not show preparalytic signs nor did they have general skeletal muscle paralysis. Even at the lowest dose tested (0.25 LD), however, they developed mydriasis and photophobia, which persisted for several days.     

Evolutionary and terminological analysis of the flexor digitorum superficialis,interflexorii and palmaris longus muscles in kinkajou (Potos flavus) and crab-eating racoon (Procyon cancrivorus)

The kinkajou (Potos flavus) and crab-eating raccoon (Procyon cancrivorus) are carnivores belonging to the family Procyonidae, but both species are characterized by different types of locomotion. Differences can be found in the adaptations that these two species present in the forearm muscles, such as the flexor digitorum superficialis (FDS), palmaris longus (PL) and interflexorii (IF), which have been described confusingly in previous studies. Therefore, the aim of this study was to describe these muscles in both species together with their innervations to carry out an evolutionary and terminological analysis among carnivorans. Both thoracic limbs were dissected from five P. flavus and three P. cancrivorus that had died of natural causes in Wildlife Care Centers. Two PL muscles (m. palmaris longus lateralis, PLL, and m. palmaris longus medialis, PLM) were found in P. flavus, and the IF were the only superficial flexors of the digits, whereas P. cancrivorus presented the IF and two bellies homologous to the two PLs of P. flavus, where the homologous belly of the PLM sent tendons to digits II–IV. Therefore, it was considered as the FDS due to its similarity to other carnivorans, and the lateral belly is the only PL present in P. cancrivorus. The topology, attachments and innervation of these muscles in P. flavus and P. cancrivorus allowed homologies to be established, hypothesizing their evolutionary derivation from the FDS. It also allowed the differences among PL, FDS and IF muscles to be described, concluding that most carnivorans do not have a PL.     

An Investigation of the Pathology Associated with Mass Mortality Events in the Cultured Japanese Pearl Oyster Pinctada fucata martensii at Four Farms in Western Japan

Abstract

The epidemiological and histopathological characteristics of the mass mortality of cultured Japanese pearl oysters Pinctada fucata martensii were investigated. Rearing experiments with Japanese pearl oysters in farms revealed that the mass mortality occurs as a regular annual event in particular farms in western Japan. Diseased oysters had marked atrophy and red-brown discoloration of the soft parts of the body. Light microscopy revealed that the epithelia of the stomach, the ducts of the digestive diverticula (DD), and the DD themselves showed marked blebbing and necrosis to varying degrees during earlier stages of the disease. At advanced stages, muscle fibers of the adductor muscle, heart, mantle, and other parts of the body and the connective tissues of various organs involving the vascular system also exhibited considerable atrophy and necrosis. There were no remarkable changes in the branchial and pallial epithelia. No viral, bacterial, mycotic, or parasitic causative organisms were found in diseased oysters. The results of a case study of mass mortality at one farm suggested that there is some causal relationship between outbreaks of this disease and the existence of neighboring fish farms. These findings suggest that the mass mortality is not due to an infectious disease. We discuss pathological features and possible causes of this disease.     

Protogynous hermaphroditism in Chrysoblephus laticeps (Cuvier) and C. cristiceps (Cuvier) (Teleostei: Sparidae)

A histological study of the gonads of two sparid fishes, Chrysoblephus laticeps and C. cristiceps showed that these species are protogynous hermaphrodites. Both species are also monandric in which all males are derived from functional females. Intersexual individuals were restricted to a narrow size range between females and males, and no evidence for simultaneous hermaphroditism was found. Similar to other sparids, the development of the ovary and testis was delimited by a connective tissue layer.     

The Muscles of the Infrapubic Abdominal Wall of a 6‐month‐old Crocodylus niloticus (Reptilia: Crocodylia)

The muscles of the infrapubic abdominal wall of crocodilians play an important role in their ventilatory mechanism. Yet the anatomy and homology of these muscles is poorly understood. To gain new insights into the anatomy of the crocodilian infrapubic abdominal wall, we dissected a specimen of Crocodylus niloticus. Origin and insertion of the muscles, as well as their arrangement relative to each other was examined in great detail. The findings were compared with those of other crocodilian taxa to detect potential variability of the muscles of interest. The homology of the muscles was studied by comparing the muscles of the crocodilian infrapubic abdominal wall with those of other diapsids. In Crocodylus niloticus, the infrapubic abdominal wall consists of four muscles: Musculus truncocaudalis, M. ischiotruncus, and Mm. rectus abdominis externus and internus. The arrangement of the muscles of the infrapubic abdominal wall of Crocodylus niloticus is consistent with that found in most other crocodilian taxa. In some crocodilian taxa, an additional muscle, M. ischiopubis, is found. In the remaining diapsids, only M. rectus abdominis is present. The crocodilian M. truncocaudalis, M. ischiotruncus and, if present, M. ischiopubis appear to be derivates of M. rectus abdominis; the development of those might be related to the evolution of the unique crocodilian ventilatory mechanism.     

The Hindlimb Myology of Tyto alba (Tytonidae,Strigiformes, Aves)

This work is the first myological dissection performed in detail on the hindlimb of Tyto alba. Six specimens were dissected and their muscle masses were obtained. T. alba has the classical myological pattern present in other species of Strigiformes, such as a well‐developed m. flexor digitorum longus and the absence of the m. plantaris, flexor cruris lateralis and ambiens. Also, T. alba lacks the m. extensor propius digiti III, m. extensor propius digiti IV and m. lumbricalis, present in the Strigidae. Hindlimb muscle mass accounts for 14.13% of total body mass, which is within the range of values of both nocturnal (Strigiformes) and diurnal (Falconidae and Accipitridae) raptors. This study provides important information for future studies related to functional morphology and ecomorphology.     

Mm. scaleni of the Ox (Bos taurus L)*)

The Mm. scaleni of 20 bovine cadavers were dissected and their attachments and nerve supply are described and illustrated. The literature is reviewed and the principles of subdividing the muscles are discussed. The emerging roots of the brachial plexus rather than the axillary vessels are taken as the dividing line between the middle and ventral scalene muscles. This principle can also be applied to the other domesticated species. Fascicles formerly described as M. iliocostalis cervicis are grouped with the M. scalenus medius as its Pars superficialis on the ground of their nerve supply. The scalene muscles are innervated by the ventral branches of spinal nerves C4—T2. The subdivisions and innervation in the ox are as follows: 1. M. scalenus dorsalis, C5—T2. 2. M. scalenus medius: Pars superficialis, C4—C8; Pars profunda, C8. 3. M. scalenus ventralis, C4—T2.     

Pineal system of desert rodents and its relationship to the epithalamus

The morphological relationships of the pineal complex to the epithalamic structures have been examined at light microscopic level in five desert rodent species, Meriones crassus , Meriones lybicus , Gerbillus gerbillus , Psammomys obesus and Ctenodactylus vali . The pineal complex is classified as type ABC in M. crassus and G. gerbillus, AC in M. lybicus, AβC in P. obesus and αβC in C. vali. In these rodent species, the pineal is an elongated organ which is dumbbell-shaped in G. gerbillus and M. lybicus, and extends above the cerebral hemispheres in M. crassus , leaf-shaped in P. obesus and lancet-shaped in C. vali. In P. obesus, pigment-containing cells are noted in the superficial part of the gland. In all species examined, the suprahabenular recess which is an extension of the choroid plexus of the third ventricule establishes a close anatomical relationship with the deep pineal. In C. vali, the suprahabenular recess is also contiguous with the pineal stalk and the superficial pineal component. In M. lybicus, M. crassus, G. gerbillus and P. obesus , a prominent dorsal vessel, the vena cerebri magna , intervenes between the suprahabenular recess, the superficial portion and the stalk. The most striking feature noted in this study is the presence of numerous melanocytes in the connective tissue capsule of the pineal gland, in the connecting stalk and in the connective tissue core of the highly convoluted suprahabenular recess in M. lybicus and M. crassus . The location of melanocytes in the restricted pineal area may suggest that these cells have a morphosignificance in photoreception or photoprotection.     

Anatomical Evaluation of the Thoracolumbar Nerves Related to the Transversus Abdominis Plane Block Technique in the Dog

Transversus abdominis plane (TAP) is a fascial plane containing the thoracolumbar nerve branches that innervate the abdominal wall. Limited information is available on the anatomical organization of these nerve branches in the dog, which is of great importance for the success of the TAP block anaesthetic technique. The aim of this study was to describe the origin and conformation of thoracolumbar nerves running through the TAP in 20 hemi‐abdominal walls of 10 adult mongrel dog cadavers with an average body weight of 12.6 kg (range: 9.6‐15.6). The abdominal walls were dissected from superficial to deep direction, the skin and both obliquus externus abdominis and obliquus internus abdominis muscles were dissected and reflected dorsally to expose the transversus abdominis muscle and the thoracolumbar nerve branches located in this plane. The anatomical features of ventral nerve branches were described. The thoracic nerve branches: T7–T12 and costoabdominalis; and the lumbar nerve branches: iliohypogastricus cranialis, iliohypogastricus caudalis, ilioinguinalis and cutaneus femoris lateralis were identified in all the cadavers. Anatomical variations related to the presence or absence within the TAP of the T7, T8 and T9 nerve branches were found. These variations should be taken into account when planning the TAP block technique in dogs.     

Distribution and numbers of mucous glands in the horse trachea

Horses commonly suffer from respiratory diseases associated with excess secretions in the airway lumen, some of which are presumably derived from airway mucous glands. However, these structures have been little investigated in the horse. Accordingly, we describe here the number, distribution and size of equine tracheal mucous glands, and compare the data with similar information for other mammalian species. Two types of gland acini were present. In the thick connective tissue, up to 400 microm beneath the epithelium, gland acini were grouped in thin sheets that, in cross-section, averaged 20 microm thick and were up to 4.0 mm in length. However, it is probable that most sheets had maximal diameters much less than 4.0 mm. Between 400 to 900 microm below the epithelium, the connective tissue was much more diffuse, and glands were larger and more globular. Gland volume in the ventral portion was approximately 1.7 microl/cm2 of mucosal surface, and approximately 1.1 microl/cm2 in the dorsal portion. Glands were somewhat more abundant between, rather than over, the cartilaginous rings, but the difference between the 2 locations was not marked. Mucous gland openings were small (20 microm diameter) and very unevenly distributed, generally occurring about 100 microm apart in longitudinal rows of about 5. Average frequency of openings in the ventral portions of 3 tracheas was approximately 1.0/mm2 of mucosal surface. The volume of individual glands was therefore approximately 17 nl. Although the frequency of gland openings in the horse trachea is similar to that for the tracheas of other large mammalian species, horse tracheal gland volume was only about 15% that of the other species. Therefore, the excess 'mucous' secretions seen in equine recurrent airway obstruction and other respiratory diseases are unlikely to be caused by comparatively high levels of airway mucous gland secretion. Instead, they may be caused mainly by hyperplasia of the mucus-producing cells of the surface epithelium or by vascular transudation.     

Identification of immunohistochemical localization of irisin in the dwarf hamster (Phodopus roborovskii) tissues

Irisin is mainly secreted by heart and skeletal muscle cells. It is an exercise‐induced protein that converts white adipose tissue to brown. Increased irisin expression was lead to weight loss and improved glucose tolerance. We investigated irisin immunoreactivity in various tissues of the dwarf hamsters (Phodopus roborovskii). Tissues were processed, embedded in paraffin, sectioned at 5 μm and stained immunohistochemically for irisin. In the retina, irisin was found almost all layers, except outer nuclear layer. Also, irisin immunoreactivity was observed in the skin, cornea, striated muscle, parotid gland, tongue, oesophagus, stomach and small intestine. The findings from this study support the notion that skeletal muscle is not the primary source of irisin.     

Histo-ontogenetic study of the parotid salivary gland of Indian buffalo

The present study was aimed at elucidating the histogenesis of parotid gland of buffalo. The study was carried out on buffalo foetuses (n = 36), during different stages of prenatal life. The foetuses were categorised into three groups based on their curved crown rump length (CVRL). The primordial anlage of parotid salivary gland was evident at 40th day of development whereas the primary ducts, in the form of cords, were first observed at 81st day of prenatal life. The capsule formation as well as the lobulation of the gland was initiated at 127th day. At 141st day, the duct system of gland was completed. The terminal tubules attained the structure of acini at 167th day. The myoepithelial cells first appeared as flattened basal cells initially around the developing acinar cells at 167th day. The typical compound tubulo-acinar nature of the gland was first observed at 185th day. Purely serous acinar cells were seen from 185th day onwards. The micrometrical studies revealed that the mean diameter of acinar cells, intercalated ducts, striated ducts and large ducts increased with the advancement of age. The serous acinar cells were devoid of acidic as well as neutral mucopolysaccharides in prenatal age groups; however, large ducts with goblet cells exhibited positive reaction. Combined PAS-AB method revealed mixed reaction in acinar cells as well as in large ducts. Fine lipid droplets were observed in intralobular as well as interlobular connective tissue; however, phospholipids were observed in the cell membrane of secretory cells and ducts.     

Vimentin-and Desmin-Positive Cells in the Moulting Budgerigar (Melopsittacus undulatus) Skin

The distribution of vimentin- and desmin-positive cells in the budgerigar (Melopsittacus undulatus) dermis was investigated by means of immunohistochemical reactivity with the commercially available (Euro-Diagnostics) polyclonal antibodies. The staining pattern for vimentin in the paraffin sections was generally comparable to that in other animal species with regard to endothelial cells, vascular wall cells, muscle cells and fibroblasts. The modified Schwann cells in the inner core of the Herbst corpuscles reacted distinctly with anti-vimentin and anti-desmin. Some connective tissue cells in the superficial dermal layer, in the feather papilla and along the pulp core inside of the regenerating feathers were particularly well stained with anti-vimentin. Fibroblast-like cells of the regenerating feathers, particularly at the base of the pulp, also reacted strongly with anti-desmin. The findings were discussed with regard to references.     

Blood vessels within lymph nodes: a comparison between pigs and sheep

In sheep, most blood vessels enter the lymph nodes at a discrete hilus, which is where the capsule overlies medullary tissue. In pigs, vessels within the node arise from an extensive network of arteries on the surface, and most vessels penetrate the capsule where it overlies diffuse tissue--the counterpart of the sheep medulla. In both species the blood vessels divide extensively as they approach and supply the dense lymphoid tissue which contains lymph nodules. The blood vessels within sheep lymph nodules are surrounded by a thick layer of amorphous material. The dense lymphoid tissue has an abundant network of venules which have smooth muscle cells in their walls. These venules are involved in lymphocyte migration and in pigs they are lined by high endothelium which is similar to that in most other species, while in sheep the endothelium is much lower. Fenestrated capillaries occur in both pig and sheep lymph nodes.     

The structure of the lachrymal glands of the domestic fowl and of the duck.

The histology of the lachrymal glands of the duck and fowl is similar. In both birds the gland is a compound tubulo-acinar structure, lobulated and invested by a thin connective tissue capsule. Foci of lymphocytes, but few plasma cells, are found in the glands. Moderately acidic mucosubstances predominate in the gland of the fowl whereas sialomucins are found in that of the duck. Neutral lipids were detected only in the gland of the fowl.     

泰和乌骨鸡胚后肝脏组织结构的发育性变化

为在实际生产中配制适合泰和乌骨吗胚后肝脏结构发育特点的饲粮提供形态学依据，本试验通过石蜡切片和HE染色的方法，研究泰和鸟骨鸡胚后肝脏显微结构的发育性变化，结果表明，胚后1d的肝脏被膜极薄，肝细胞数量很少，双核细胞较多，肝小叶不明显，血窦清晰，肝细胞内、外含有大量的脂滴。胚后7d，肝被膜薄，被膜下肝细胞体积较大，内含较多脂滴，但靠近中央部的肝细胞内脂滴逐渐消失，血窦较清晰。胚后14d，肝脏被膜有所增厚，被膜下肝细胞内仍然含有较多脂滴，其他结构与7d类似。胚后21d，肝被膜相对较厚，结缔组织相对前期较发达，有少量被膜结缔组织深入实质内，肝血窦相对较少，其他结构与14d类似。第28天，肝细胞与早期比较，体积较小，无脂滴，胞质染色深。肝细胞排列呈肝细胞管作辐射状排列，且相互吻合。肝细胞管中央形成胆小管。窦周隙明显。肝细胞结构和排列方式符合典型的禽类特点。