RADIOGRAPHIC ANATOMY OF THE CRIBRIFORM PLATE (LAMINA CRIBROSA)

The radiographic appearance of the cribriform plate was investigated in 16 canine cadaver heads. The cribriform plate appeared as a "V"-shaped multilinear bone-opaque stripe in the caudal nasal region in projections perpendicular to the hard palate in 6 dogs with a skull index between 50.00 and 54.00. In 9 dogs with a skull index between 55.40 and 74.40, the cribriform plate had a more "C"-shaped and sharp appearance. In vertically oblique projections with an obliquity greater than 20 degrees, the cribriform plate lost its sharp outline and finally (40 degrees) disappeared. In lateral projections the cribriform plate appeared as a "C"-shaped interrupted bone-opaque stripe in all 16 dogs. In more brachycephalic dogs frontal bone structures superimposed on the cribriform plate on ventrodorsal and dorsoventral views and accentuated the radiographic appearance of the plate. Vertically oblique views separated both structures to produce two lines.     

The morphology and incidence of supraependymal structures in the cerebral ventricle system in sheep

The morphology and distribution of supraependymal structures in the ventricular system of sheep of both sexes were studied by common histological methods. Seven forms of supraependymal structures were distinguished according to shape; they are most frequent and most variable in the infundibular region of the third cerebral ventricle. In the ewes their occurrence in this region depends on the status of the ovarian cycle and in the rams it depends on the year season. The most frequent forms are hemi-spherical to spherical light-coloured protrusions and the so-called blebs: in the ewes they occur during anoestrus and, to a minor extent, during proestrus, and in rams in the "rest" period. In the winter reason (the rest period) the rams have button-like formations on ependyma surface in the infundibular region, and in summer there are finger-like protrusions. No such structures occur in the ewes. A larger part of the supraependymal structures are believed to be products of ependyma secretion which, in the infundibular region but nowhere else, is associated with sex: with the ovarian cycle in the ewes and with the year season in the rams.     

Neutropenia associated with osteomyelitis due to Hepatozoon canis infection in a dog

A 4-year-old, intact male Shiba dog was referred to Yamaguchi University Animal Medical Center, Yamaguchi, Japan, for the following complaints: anorexia, lethargy, intermittent fever, gingival bleeding and abdominal purpura. The dog presented with persistent neutropenia. Histopathological examination of a bone marrow sample revealed round to oval structures that resembled Hepatozoon micromerozoites and formed a "wheel-spoke" pattern. Furthermore, mature neutrophils were observed around these structures. PCR and sequencing using bone marrow aspirate confirmed Hepatozoon canis (H. canis) infection. These findings suggest that the neutropenia observed in this case was associated with osteomyelitis due to H. canis infection. This is the first report of neutropenia associated with H. canis infection. H. canis infection can be included in the differential diagnosis in canine cases of neutropenia in areas where the disease is endemic.     

Skin histology and its role in heat dissipation in three pinniped species

Background

Pinnipeds have a thick blubber layer and may have difficulty maintaining their body temperature during hot weather when on land. The skin is the main thermoregulatory conduit which emits excessive body heat.

Methods

Thorough evaluation of the skin histology in three pinniped species; the California sea lion-Zalophus californianus, the Pacific harbor seal-Phoca vitulina richardsi, and the Northern elephant seal-Mirounga angustirostris, was conducted to identify the presence, location and distribution of skin structures which contribute to thermoregulation. These structures included hair, adipose tissue, sweat glands, vasculature, and arteriovenous anastomoses (AVA). Thermal imaging was performed on live animals of the same species to correlate histological findings with thermal emission of the skin.

Results

The presence and distribution of skin structures directly relates to emissivity of the skin in all three species. Emissivity of skin in phocids (Pacific harbor and Northern elephant seals) follows a different pattern than skin in otariids (California sea lions). The flipper skin in phocids tends to be the most emissive region during hot weather and least emissive during cold weather. On the contrary in otariids, skin of the entire body has a tendency to be emissive during both hot and cold weather.

Conclusion

Heat dissipation of the skin directly relates to the presence and distribution of skin structures in all three species. Different skin thermal dissipation patterns were observed in phocid versus otariid seals. Observed thermal patterns can be used for proper understanding of optimum thermal needs of seals housed in research facilities, rescue centers and zoo exhibits.     

Radiographic study of the maxillary canine tooth of four mesaticephalic cats

The radiopaque and radiolucent anatomical structures that are superimposed over the root of the maxillary canine tooth in mesaticephalic cats were identified on digital radiographs made at various angles. The vomer bone, the nasal bone, the palatine fissure, and the infraorbital foramen were not superimposed over the root of the canine tooth in the range of angles examined. Superimposition with the palatine sulcus (which is rarely visible clinically because of silhouetting of the soft tissues) only occurred at extreme horizontal (cross-sectional arc) angles. The second premolar tooth was superimposed at a cross-sectional angle of 80 degrees and 90 degrees. The structures of concern in the interpretation of radiographs of the maxillary canine tooth in mesaticephalic cats are the conchal crest, the line of conjunction between the vertical body of the maxilla and its palatine process, the incisivomaxillary canal (which is rarely visible on radiographic images), and the lachrymal canal. Because of their anatomical vicinity, the radiographic position of these structures relative to the maxillary canine tooth can only be minimally changed. It was not possible to identify an "ideal" angle to radiograph the maxillary canine tooth in these four mesaticephalic cats. However, an acceptable compromise between minimal distortion of the image and satisfactory visualization of the root was obtained with the radiographic beam (rostro-caudal rotation) angled at 80 degrees and the skull (rotation in cross-sectional arc) angled at 70 degrees.     

Structural changes in femoral bone tissue of rats after subchronic peroral exposure to selenium

Background

The role of selenium (Se) on bone microarchitecture is still poorly understood. The present study aims to investigate the macroscopic and microscopic structures of femoral bone tissue in adult male rats after subchronic peroral administration of Se.

Methods

Twenty one-month-old male Wistar rats were randomly divided into two experimental groups. In the first group (Se group) young males were exposed to 5 mg Na₂SeO₃/L in drinking water, for 90 days. Ten one-month-old males without Se administration served as a control group. At the end of the experiment, macroscopic and microscopic structures of the femurs were analysed using analytical scales, sliding instrument, and polarized light microscopy.

Results

The body weight, femoral length and cortical bone thickness were significantly decreased in Se group rats. These rats also displayed different microstructure in the middle part of the femur, both in medial and lateral views, where vascular canals expanded into the central area of the bone while, in control rats, these canals occurred only near the endosteal surfaces. Additionally, a smaller number of primary and secondary osteons was identified in Se group rats. Histomorphometric analyses revealed significant increases for area, perimeter, maximum and minimum diameters of primary osteons’ vascular canals but significant reductions for all measured variables of Haversian canals and secondary osteons.

Conclusions

Se negatively affected the macroscopic and microscopic structures of femoral bone tissue in adult male rats. The results contribute to the knowledge on damaging impact of Se on bone.     

Inherited myopathy in a young Great Dane

A 3-year-old, male Great Dane was evaluated for an 18-month history of progressive weakness. Histologic evaluation of muscle biopsies revealed distinct cytoarchitectural changes that were indistinguishable from the central "core-like" structures previously described as central core myopathy in this breed. Clinical features of this inherited myopathy are described.     

Simulation of local anaesthetic nerve block of the infraorbital nerve within the pterygopalatine fossa: anatomical landmarks defined by computed tomography

To provide anaesthesia of the maxillary cheek teeth, a local block of the infraorbital nerve in the pterygopalatine fossa has been suggested. The aim of this study was to re-examine the anatomy of the pterygopalatine fossa, giving special attention to relevant arteries, veins and nerves; simulate the infiltration of an anaesthetic by injecting a contrast medium; improve the injection technique to avoid puncturing of relevant anatomical structures. Five heads and two living horses were investigated using contrast medium injections and computed tomography (CT). Needles were inserted using two insertion techniques: "Palatine Bone Insertion" (PBI) and "Extraperiorbital Fat Body Insertion" (EFBI). Both techniques are suitable for achieving a consistent distribution of contrast medium around the infraorbital nerve. The periorbita prevents the contrast medium from penetrating into the intraperiorbital compartment. The EFBI-technique is most appropriate for providing a sufficient infraorbital nerve block with a minimised risk of complications.     

Corpus Callosal Abnormalities in Dogs

Background

Corpus callosal abnormalities (CCA) in dogs have been only sporadically reported and are poorly characterized.

Hypothesis/Objectives

To describe the clinical presentation and magnetic resonance imaging (MRI) characteristics of dogs with CCA.

Animals

Fifteen client‐owned dogs.

Methods

Retrospective study. Records of the contributing institutions were reviewed to identify dogs diagnosed with malformations affecting the corpus callosum (CC); cases in which the CCA was thought to be secondary were excluded.

Results

The most represented breeds were Staffordshire Bull Terriers (5/15) and Miniature Schnauzers (3/15; n = 3, 20%) and the mean age at time of presentation of 19 months (range 3–81 months). The clinical signs most commonly reported were adipsia/hypodipsia with associated hypernatremia (12/15), tremors (6/15), and seizures (6/15). Review of the MR images revealed that 10 dogs had absence of the rostral CC and hypoplasia of the caudal portion, 4 dogs had a diffusely hypoplastic and dysplastic CC, and 1 dog had a diffusely hypoplastic CC. In 14 cases, there was abnormal cortical development with fusion of the ventral frontal lobes and part of the diencephalon, indicating lobar holoprosencephaly.

Conclusions and Clinical Importance

Previous literature has mainly associated CCA with adipsia and only 12 of 15 dogs in the current series demonstrated this abnormality. There are different degrees of the malformation but in 10 dogs the rostral portion of the CC is most severely affected. Fourteen dogs have simultaneous fusion of the midline structures rostral to the CC; this region has several structures involved in thirst regulation and might explain this derangement.     

Changes in intracellular and cell surface localization of Le(x) epitope during germ cell differentiation in fetal mice.

Changes in the intracellular and cell surface localization of Lewis x (Le(x)) determinants in germ cells during fetal development in mice were examined by light and electron microscopy. Light microscopically, in undifferentiated gonads on day 12 post coitum (p.c.), the anti-Le(x) monoclonal antibody (MAb) was specifically bound to the plasma membranes and to the cytoplasmic granule-like structures of germ cells. In the testes on day 13 p.c., most of the germ cells were enclosed within the testicular cords and showed an MAb-positive reaction which was restricted mainly to the cytoplasmic granule-like structures. The reaction on the plasma membranes almost disappeared. On the other hand, the ectopic germ cells still showed a positive reaction on their plasma membranes. In the ovaries on day 13 p.c., the germ cells also exhibited positive reactions both on the plasma membranes and on the granule-like structures. Immunoelectron microscopic observations agreed well with these light microscopic observations in such a way that both the plasma membranes and the "small dense bodies" (SDB) were positive in undifferentiated gonads on day 12 p.c. In the germ cells organized into the testicular cords, the reaction to anti-Le(x) MAb became restricted to the SDB. These results may indicate that such intracellular changes in Le(x) determinants during germ cell differentiation are associated with the enclosure of germ cells within the testicular cords.     

Multivariate genetic evaluation in swine combining data from different testing schemes

A computational strategy is presented that allows rapid implementation of genetic evaluations using multivariate mixed models. Data generated in different testing programs such as field tests of boars and gilts, litter recording schemes and station tests of sibs may be combined to provide an estimate of the aggregate genotype. Residual and additive genetic covariance structures are given for the multivariate evaluation of individual measurements and group averages because they often are collected for sib groups at test stations using a modified animal model. Pseudo code is given for the implementation of a "generic" testing structure illustrated by a numerical example based on six traits from field tests of boars and four traits from station tests of sibs. BLUPs for all six traits are calculated for boars, parents and sib groups. Aggregate genotypes that correspond to the selection indices commonly used are calculated for selection candidates.     

Cell-to-cell attachments and associations in tumors induced by CELO virus or virus-transformed cells in hamsters.

Cell-to-cell attachments or associations in expermentally induced sarcoma of chicken embryo lethal orphan virus (avian adenovirus) origin were studied in hamsters by electron microscopic examination. In many instances, the neoplastic cells seemed to be held together either by desmosome-like structures or an "interlocking" of their apposing plasma membranes. Less frequently, the cells were attached by button-like projections between the cell surfaces. Only rarely, interdigitation occurred between filopodial processes of cell surface of adjoining cells.     

An in vitro effect of propolis on adult worms of Fasciola gigantica

The effect of Siwa propolis on adult flukes was evaluated using scanning electron microcopy. It gave an overview of the surface architecture of the tegument of Fasciola gigantica apical cone. The base of the spines appeared to be "flaking off" and showed severe blebbing after 24h incubation with 10 micro/ml propolis. This swelling became so sever and the spines were barely visible, on increasing the concentration to 20 micro/ml. Besides, there were many large blebs on the apical cone, a number of which appeared to have burst, causing lesions and the tegument was marked by a number of pits caused by the loss of spines. With the higher concentration of 30 micro/ml, erosion of the surface had occurred to such extent that no tegument remained, only a mass of fibrous structures. The tegumental changes occurred following incubation in propolis were compared with those observed with triclabendazole (TCBZ) "Fasinex" because of its high efficacy against both mature and immature flukes.     

The ultrastructure of macrophages in granulomatous colitis of Boxer dogs.

Thirteen cases of granulomatous colitis of Boxer dogs were studied by electron microscopy to define the contents of macrophages and to seek infectious agents. Macrophages were of three types. The most numerous were distended with residual bodies composed of membranes and parallel pairs of membranes, many arranged in circular patterns. A second common form had heterogeneous cytoplasm distended with phagosomes containing numerous small granular spheres of various sizes and electron densities. The least common were "young" macrophages containing phagocytic vacuoles. Rare macrophages in four of 13 dogs contained bacteria. Macrophages in five of the dogs contained abundant coccoid, coccobacillary of lobulated granular structures, 100-500 nm in diameter, resembling chlamydia. Transition from phagocytic particle to phagosome to residual body was apparent. Granulomatous colitis of Boxer dogs is probably caused by a lipid-rich, ribosome-rich, coccoid to coccobacillary organism that possesses a cell membrane and sometimes a nucleoid, and ranges from 100 to 500 nm in size.     

Magnetic resonance imaging anatomy of the rabbit brain at 3?T

Background

Rabbits are widely accepted as an animal model in neuroscience research. They also represent very popular pet animals, and, in selected clinical cases with neurological signs, magnetic resonance imaging (MRI) may be indicated for imaging the rabbit brain. Literature on the normal MRI anatomy of the rabbit brain and associated structures as well as related reference values is sparse. Therefore, it was the purpose of this study to generate an MRI atlas of the normal rabbit brain including the pituitary gland, the cranial nerves and major vessels by the use of a 3 T magnet.

Results

Based on transverse, dorsal and sagittal T2-weighted (T2w) and pre- and post-contrast 3D T1-weighted (T1w) sequences, 60 intracranial structures were identified and labeled. Typical features of a lissencephalic brain type were described. In the 5 investigated rabbits, on T1w images a crescent-shaped hyperintense area caudodorsally in the pituitary gland most likely corresponded to a part of the neurohypophysis. The optic, trigeminal, and in part, the facial, vestibulocochlear and trochlear nerves were identified. Mild contrast enhancement of the trigeminal nerve was present in all rabbits. Absolute and relative size of the pituitary gland, midline area of the cranial and caudal cranial fossa and height of the tel- and diencephalon, 3rd and 4th ventricles were also determined.

Conclusions

These data established normal MRI appearance and measurements of the rabbit brain. Results provide reference for research studies in rabbits and, in rare instances, clinical cases in veterinary medicine.

Electronic supplementary material

The online version of this article (doi:10.1186/s13028-015-0139-6) contains supplementary material, which is available to authorized users.     

Interior openings of functional pores in the avian egg shell: Identification with the scanning electron microscope

1. In a method to identify interior openings of unobstructed pores, they are stained with uranyl acetate.

2. Back‐scattered electron atomic number contrast imaging indicates the openings of those pores that have been penetrated by the stain, because of the enhanced back‐scattering arising from the atomic number difference between uranium and calcium. Morphologically identical structures that are unstained do not contribute to the total effective pore area.     

The use of the plasma chemistry unit as an aid to the scanning electron microscope study of avian egg‐shell structure

1. In order to study the mammillary layer of the avian egg shell by scanning electron microscopy, it is necessary to separate the outer shell membrane from the calcified shell.

2. Chemical methods of effecting membrane removal are difficult to standardise due to variations in the strength of the membrane‐shell bond.

3. The use of reactive gas plasma provides an alternative, more efficient method for removing membranes without the risk of damage to underlying crystalline structures.     

Chronic periorchitis and periepididymitis of cattle

The Authors describe chronic vaginitis of bovines in intensive breeding. All of the 78 subjects examined presented vaginitis, accompanied by fibrinous hydrocele. On the spermatic cord and the tail of epididymis, initial lesions consisted of granulomas and fibrinous bridges between vaginalis propria of testicle and of epididymis. Subsequently appeared adherence and synechiae, which join the deferens and epididymis body to didymis, and thickening of albuginea. Synechiae can develop between peritesticular vaginalis propria and communis. Histopathological findings: peritoneal-like papillary structures with metaplastic mesothelial cells; diffuse lympho-plasmacellular infiltration with eosinophils and mast cells; intense capillary angiogenesis. The epididymal lesions are: diffuse mononuclear infiltration; periarteritis nodosa; papillary proliferations of endothelium; endothelial degeneration; tubular ectasia and stenosis; intraepithelial cyst. Noticeable within testis: periarteritis nodosa; fibrosis of albuginea; spermatocytes vacuolisation; multinucleate spermatids; epithelial shedding. The Authors pointed out: the serological and bacteriological testings furnished inconclusive results; only pathological finding always present is a large infestation of cremasteric muscle with Sarcocystis, to which is attributed the etiopathogenesis of flogosis, that is chronic from the beginning. The Authors propose the terminology of "Chronic peritesticular and periepididymal vaginitis" or "Chronic Periorchitis and periepididymitis".     

Hepatocellular carcinoma with metastasis to the spleen in a Holstein cow

Hepatocellular carcinoma (HCC) with metastasis to the spleen in a Holstein cow was studied by histopathologic and immunohistochemical methods. The tumor was characterized by a pseudoglandular (acinar) pattern with an associated fibrous stroma. Individual cells often had a "hepatoid" appearance but were interspersed with scattered cells exhibiting a clear, periodic acid-Schiff (PAS)-positive cytoplasm and small eccentric nuclei. This pattern was present in nodules found in both liver and spleen. Moreover, hepatoid tumor cells were positive for alpha-fetoprotein. Immunohistochemical studies suggest that myofibroblasts were responsible for the production of fibrous septa surrounding the pseudoglandular structures of bovine HCC. In summary, our histologic and immunohistochemical findings support a diagnosis of primary HCC with splenic metastasis. Furthermore, the associated stromal response appears to be of a myofibroblast origin. The primary etiology of bovine HCC and the significance of the intralesional, PAS-positive clear cells remain undetermined.     

Blind versus ultrasound-guided maxillary nerve block in donkeys

Objectives

To describe the ‘blind’ and ultrasound-guided approaches to block the maxillary nerve in donkeys. To compare the success and complication rates between the ‘blind’ and ultrasound-guided techniques based on staining of nerves and other structures in cadavers and assessing level of analgesia in live animals.