Ventral Gland Research Articles

Two new species of the order Monhysterida (Nematoda) from the sea of China.

Two new marine nematode species belonging to the order Monhysterida are described from the sea of China. Halomonhysterazhangisp. nov. is characterized by its relatively small body size; short anterior sensory setae; small, circular amphidial fovea located at the level of buccal cavity base; funnel-shaped buccal cavity; an excretory-secretory system with a large ventral gland and opening as a very narrow canal just posterior to the level of cephalic setae; slightly curved slender spicules with cephalated proximal end and tapered distal end; rod-like gubernaculum without apophysis; two papilliform precloacal supplements just in front of the cloaca; conico-cylindrical tail with two ventral papillae, each with a seta; and distance between the vulva and anus slightly longer than the tail length. This is the first new species of epiphytic nematode reported in China. The second new species, Stylotheristusflagellicaudatussp. nov., has a relatively shorter body and longer tail; striated cuticle; The anterior sensilla arranged in two circles, the first circle consisting of six inner labial setiform papillae (3-4 µm) and the second circle consisting of 16 long setae (12-19 µm); a transversely oval amphideal fovea; a well-developed muscle around the funnel-shaped buccal cavity; short spicules and a gubernaculum composed of a single piece; and precloacal supplements absent. An updated key to all species of Halomonhystera and pictorial key to all species of Stylotheristus are also given.

New deep-sea species of Aborjinia (Nematoda, Leptosomatidae) from the North-Western Pacific: an integrative taxonomy and phylogeny.

Marimermithid nematodes parasitising invertebrates are mainly found in the deep-sea environments. Several adult and juvenile specimens marimermithids of the genus Aborjinia have been found in bottom sediments and inside Polychaeta during recent cruises to the Kuril-Kamchatka trench and the Kuril Basin (the Sea of Okhotsk). New species are described based on integrative study. Aborjiniaprofundasp. nov. differs from A.eulagiscae by the location of the ventral gland cell bodies (posterior to the nerve ring vs posterior to the cardia), by the smaller body size (23-28 mm vs 103-132 mm) and shorter tail (193-263 µm vs 500-850 µm). BI and ML phylogenetic analyses based on 18S and 28S rDNA suggest that genus Aborjinia belongs to the family Leptosomatidae. Based on molecular and morphological characters the new genus Paraborjiniagen. nov. is proposed for A.corallicola. Within the family Leptosomatidae the new genus differs from all genera except Aborjinia by its endoparasitic lifestyle and hologonic ovaries. Paraborjiniagen. nov. differs from Aborjinia by the position of cephalic sensitive organs (outer labial and cephalic papillae in two separate circles vs outer labial and cephalic papillae in one circle) and by the parasitic adult (vs free-living in Aborjinia).

Анатомия клоаки углозубов рода Salamandrella (Amphibia: Caudata, Hynobiidae)

In salamanders, anatomy of the cloacae is varying among families and inside of them. Futures of this organ and the cloacal glands are interesting for understanding of the levels of differentiation between close species of amphibians, because these structures perform some functions which important for reproduction. We studied the male and female anatomy of cloacae in two cryptic species Sala-mandrella keyserlingii and S. tridactyla via histological analyses and methods of digital 3D-recontstruction. F or histological study, we used whole cloacal samples fixed in 10% formalin, dehydrated them in graded series of ethanol solutions (70%, 96%, and absolute ethanol), clarified in butanol, and embedded in paraffin for histology. We cut paraffined organ’s samples (10 m sections) via rotary microtome. We used Mayer’s hae-matoxylin-eosin, Masson-Goldner’s trichrome, and modified azan for observation general histology, PAS-staining for detection of carbohydrates (PAS), alcian blue (AB) pH = 2,5 for visualization of mucopolysaccharides, and Coomassie blue (CB) for protein detection. We made 3D-reconstuction via software Free-d, using serial photos of cloacal sections. We found that these species have the same structure of the cloacae and only the ventral glands secreting neutral glycoproteins, because secretion had PAS+, AB-, and CB+ reactions. There were a slight variability of form of the cloacal chamber and cloacal gland topography dependent on sex or species (See Figs. 1-6), but this variation is not important from the point of view of function. These features of the male and female cloacal structure and histochemistry of cloacal glands in species of the genus Salaman-drella bring them closer to other members of the family Hynobiidae, with the exception of the genus Onychodactylus, whose males have three types of cloacal glands. This is consistent with modern views on the phylogenetic relationships of hynobiids. The article contains 6 Figures, 26 References. The Authors declare no conflict of interest.

Ovarian papillary carcinoma in a Mongolian gerbil (Meriones unguiculatus)

Neoplasms are among the most impacting disease diagnoses in veterinary medicine and have become increasingly common due to the greater longevity of animals as living conditions improved. The Mongolian gerbil is a small rodent species that has become popular recently. In these animals, the occurrence of neoplastic processes is relatively common, mainly tumors of the ventral gland in males and ovarian tumors in females. This work aims to report an ovarian tumor in a Mongolian gerbil Meriones unguiculatus Milne-Edwards 1867 (Rodentia, Muridae). At the initial presentation, the animal had dyspnea, prostration, and increased abdominal volume in the topography of the right ovary of approximately 2 cm. The animal was submitted to exploratory laparotomy because of the emergency nature of the case and the owners’ refusal of additional exams due to financial restrictions. Thus, an ovariohysterectomy was performed, followed by a histopathological examination. The histopathology revealed an ovarian papillary carcinoma affecting both ovaries and cystic endometrial hyperplasia. With surgical removal and drainage of the thoracic fluid, the animal showed good recovery, with general improvement and return to regular activity, with a life expectancy of two years. Currently, the demand for specialized veterinarians for unconventional pets is increasing. This condition allows owners to raise their animals more properly, favoring greater longevity. Knowledge about the prevalence and incidence of diseases in different species is of enormous relevance in establishing the appropriate therapy, improving life quality, and increasing life expectancy in animals’ lives.

Reproductive behaviour, cutaneous morphology, and skin secretion analysis in the anuran Dermatonotus muelleri

SummaryDespite the common poison and mucous glands, some amphibian groups have differentiated glands associated with reproduction and usually present on the male ventral surface. Known as breeding glands or sexually dimorphic skin glands (SDSGs), they are related to intraspecific chemical communication during mating. Until recently, reproduction associated with skin glands was recognized only in salamanders and caecilians and remained unexplored among anurans. The Brazilian microhylid Dermatonotus muelleri (Muller's termite frog) is known for its very toxic skin secretion. Despite the slippery body, the male adheres to the female back during reproduction, as they have differentiated ventral glands. In this paper, we have gathered data proposing an integrative approach correlated with the species' biology and biochemical properties of their skin secretions. Furthermore, we suggest that the adhesion phenomenon is related to arm shortening and rounded body that make amplexus inefficient, although constituting important adaptive factors to life underground.

The male reproductive system in whip spiders (Arachnida: Amblypygi)

Whip spiders (Arachnida, Amblypygi), like many other soil arthropods, transfer their spermatozoa indirectly via a stalked spermatophore. While the complex courtship behavior as well as the morphological differences of spermatophores and corresponding female genitalia between taxa have received great attention in the past, comparative research on the internal reproductive system is lacking so far. In this study, the morphology of the male whip spiders of four neoamblypygid taxa has been comparatively studied via computer tomography and subsequent 3D reconstruction. We investigated four species belonging to the Neoamblypygi, that is, the phrynichid species Damon medius (Damoninae), and Euphrynichus bacillifer (Phrynichidae), the phrynid species Phrynus hispaniolae (Phrynidae), and the charontid species Charon grayi (Charontidae). The male reproductive organs consist of paired testes and two pairs of accessory glands, the ventral and lateral glands, which project their ducts anteriorly into the ventrally located unpaired spermatophore producing organ where the respective seminal and secretory reservoirs are located. While this general organization of the male reproductive system is similar among all investigated taxa, there are some notable differences in some structures. The most surprising findings include the complete absence of ventral glands in D. medius, the presence of unique spherical ventral gland reservoirs in C. grayi as well as differences in the organization of the seminal and secretory reservoirs and their connections to the inner genital slit. In addition, the secretory products of both, ventral and lateral glands, are stored in combined secretory reservoirs in E. bacillifer and P. hispaniolae. This study is the first to show that there is some morphological variation in the male reproductive system in Neoamblypygi. These results are the basis for the reconstruction of the Bauplan for the reproductive organs of the whip spiders.

Light and Electron Microscopy of Buccal Salivary Glands of the Dromedary Camel

The study was aimed to investigate the light and electron microscopic structure of buccal salivary glands in the dromedary (Camelus dromedarius). Anatomically, the dromedary camel buccal glands were well-developed and were located on the lateral side of the cheek. Three parts (groups) of the buccal glands could be observed: dorsal, middle and ventral parts. Histologically, the secretory units were tubule-acinar, surrounded by myo-epithelial cells and supported by connective tissue. Whereas, the dorsal glands were purely mucous and the ventral glands were purely serous in secretion, the middle ones were muco-serous with predominant mucous cells. Ultra-structurally, the glandular cells of the serous secretory units (type I cells) contained numerous microvilli, many electron-dense secretory granules, abundant rough endoplasmic reticulum and mitochondria. On the other hand, the mucous-secreting cells (type II cells) appeared with numerous electron-translucent supra-nuclear granules and flat basal nuclei; dilated tubules of rough endoplasmic reticulum; fewer mitochondria and Golgi bodies were also observed. The obtained results have been compared with the previous reports on salivary glands of camel and other mammalian species.

Male and Female Cloacal Anatomy of the Fischer’s Clawed Salamander, <i>Onychodactylus fischeri</i> (Caudata, Hynobiidae)

The cloaca of salamanders is a complex organ with exocrine glands involved in the production of sex pheromones, spermatophores, and storage of sperm. Since the cloaca provides reproductive functions, its signs are important for phylogenetic analysis in the evolutionary biology of tailed amphibians. For clarification of intrafamilial variation of cloacal characteristics in hynobiids, we studied the anatomy of male and female cloacae of Onychodactylus fischeri via histological, histochemical, and 3D-reconstruction methods. Males and females had ciliated cloacal linings and with sexual dimorphism in cloacal conformation and cloacal glands. As in other males and females of hynobiids, females of O. fischeri possessed only ventral glands, secreting neutral glycoproteins. In contrast, males of this species had three types of the cloacal glands. Glands «B» were like ventral glands of females and other hynobiids, while glands «A» and «C» had different histochemical and morphological characteristics. As our results are generally consistent with the data for the related species O. japonicus, these characteristics of the male and female cloacal anatomy may be common to all species of the genus Onychodactylus. The presence of three types of unique cloacal glands in males distinguishes Onychodactylus from all other hynobiids and salamanders.

The Male Urogenital System of a Salamander Ranodon sibiricus (Amphibia, Caudata)

Abstract: The male urogenital system of salamanders varies both among families and within them. To understand diversity of this system in hynobiids, we studied the gross anatomy and histology of the male urogenital system of a mountainous rheophilic salamander, Ranodon sibiricus. Males had single-lobed, lobular-cystic testes which were characterized by the presence of ‘lobular waves'. The sperm transport system included the vasa efferentia, longitudinal collecting ducts of the vasa efferentia, the genital kidneys, and Wolffian ducts leading to the cloaca. There were also rudimentary Mullerian ducts. The cloaca contained ventral glands. The structure of the male urogenital system of R. sibiricus was similar to the genera Batrachuperus, Hynobius, and Salamandrella.

Does the addition of a new signalling trait enhance receiver responses in diurnal geckos?

Animal signals in multiple modalities expands the opportunity for effective communication. Among diurnal geckos of the genus Cnemaspis, chemical signalling traits preceded the evolution of visual traits. Males of all species possess chemical secreting ventral glands, but only in some species, males also express yellow gular patches. This difference in the expression of unimodal or multimodal signalling traits between closely related species provided us with an opportunity to understand the use of multimodal signals for communication. We studied receiver responses in Cnemaspis indica, a sexually monochromatic species, and in C. littoralis, a species where males possess yellow gulars. We performed behavioural trials where individuals of each species were exposed to only chemical stimuli, only visual stimuli, or both chemical and visual stimuli simultaneously from male and female conspecifics. Our results show that only chemical stimuli were necessary and sufficient to elicit responses in males and females of C. indica as well as in females of C. littoralis. However, males of the dimorphic C. littoralis required the multimodal stimulus to elicit movement-based responses. Our results suggest that the evolution of colour traits in diurnal geckos is associated with a partial shift in some receiver responses toward multimodal communication, with no addition to the behavioural repertoire.

Characterization of the Arion vulgaris pedal gland system.

The most common European gastropod species, Arion vulgaris, is one of the most troublesome pests for private garden owners and commercial agriculturists. The sticky and hard to remove secretion produced by these animals allows them to overcome most artificial and natural barriers. However, this highly adherent biopolymer has recently shown great potential for novel wound‐healing applications in medicine. Nevertheless, our knowledge of the underlying gland system is still limited and few studies on the ventral gland system are available. We studied the lateral and ventral pedal glands in Arion vulgaris to determine their secretory content histochemically and through lectin assays. Using these histological and histochemical methods we differentiate five gland types with different mucus composition in the lateral pedal region of the foot of Arion vulgaris. These contain sulphated and carboxylated mucosubstances (positive Alcian blue staining) but lack hexose‐containing mucosubstances (negative PAS staining). In the ventral pedal region, four gland types can be differentiated producing sulphated and carboxylated mucosubstances. Within the ventral mucus, a high affinity for the lectins PNA and WGA is observed. While the lateral glands are histochemically negative for PAS, a positive staining with the lectin JAC is observed. Arion vulgaris shows clear morphological differences from other arionid species. This raises the question whether the variation in the chemistry of the secretory material and mucus composition is the result of different functions and/or is related to the animals' different environmental conditions. A comparison of some glands of Arion vulgaris with those of the helicid species Helix pomatia and Cepaea hortensis indicates morphological similarities.

New Eremidrilus species (Clitellata: Lumbriculidae) from western North America. Part 1, species with two spermathecal segments.

Four new species of the lumbriculid genus Eremidrilus Fend Rodriguez, 2003 are described from Idaho, Montana, and New Mexico. The new species all have a filiform proboscis, club-shaped atria in X, each with two functional vasa deferentia, and spermathecae paired in both XI and XII. Male pores of Eremidrilus artzaini n. sp., E. humboldti n. sp., and E. gilita n. sp. are all associated with distinctive porophores, but these structures are absent in E. montanensis n. sp. The new species are easily distinguished from California Eremidrilus species, all of which have spermathecae only in XI. New observations of type specimens of Eremidrilus allegheniensis (Cook, 1971), a species with two spermathecal segments, known only from eastern USA, confirm differences in atrial morphology, and also document unusual spermathecal porophores and ventral glands.

Carcinoma de células escamosas em gerbil (Meriones unguiculatus)

The Mongolian gerbil (Meriones unguiculatus), also known as Mongolian jird, is a rodent of the family Cricetidae. One of its most noticeable anatomical characteristics is the presence of ventral and dorsal scent glands, the former located in the abdominal region. The present study aimed at describing an incidence of squamous cell carcinoma (SCC) of the ventral scent gland in the species. A two‑year‑old animal characterized by an increased volume in the ventral abdominal region was treated at the Veterinary Hospital. After evaluating the macro- and microscopic characteristics of the mass tissue, a diagnosis of SCC could be confirmed. However, further studies on the physiology of neoplasms in Mongolian gerbils are needed in order to promote the well-being and longevity of individuals. Hormonal dysfunction of sexual origin is likely the most common factor associated with the occurrence of this type of neoplasm in the species.

Ultrastructure of the prosomal gland complex in unfed larvae of the fresh-water mite Limnesia maculata (Müller, 1776) (Acariformes, Limnesiidae)

The salivary and coxal glands in unfed larvae of the fresh-water mite Limnesia maculata (Müller, 1776) (Acariformes, Limnesiidae) were studied using light and electron microscopy. Three pairs of the salivary and one pair of the coxal glands constitute the prosomal gland complex. The salivary glands pertain to simple alveolar glands consisting of the single acinus with prismatic cells arranged around the intra-alveolar lumen. Owing to their spatial distribution, the salivary glands may be termed as medial, ventral and lateral. While the ventral and lateral glands are arranged symmetrically, the medial glands are disposed one after another at the frontal wall of the synganglion (brain). The medial and the ventral glands possess mostly electron-dense secretory granules supposedly of protein nature. The lateral glands show variable organization mainly having electron-lucent vacuoles. No well pronounced rough endoplasmic reticulum and Golgi bodies were discernible in the salivary glands. The coxal glands are well developed and composed of (i) the main portion (the so-called labyrinth) including at least two tightly opposed loops and extending backward along the brain, and (ii) the very short anterior portion/end piece transforming anteriorly into the terminal sac/bladder. The cells of the main portion are provided with apical microvilli, whereas the basal infolding/basal labyrinth is lacking. The cells of the anterior portion do not show the apical microvilli and the basal infoldings. The terminal sac is lined by a cuticle and has an ectodermal origin. The ducts of the salivary glands come together at the dorsal aspect of the bladder, to which they open forming the common podocephalic duct anteriorly. The latter opens on each side into the subcheliceral space. The well-developed podocephalic system suggests its active role in the living processes such as feeding and ion-water balance.

Comparative and functional analysis of the digital mucus glands and secretions of tree frogs

BackgroundMucus and mucus glands are important features of the amphibian cutis. In tree frogs, the mucus glands and their secretions are crucial components of the adhesive digital pads of these animals. Despite a variety of hypothesised functions of these components in tree frog attachment, the functional morphology of the digital mucus glands and the chemistry of the digital mucus are barely known. Here, we use an interdisciplinary comparative approach to analyse these components, and discuss their roles in tree frog attachment.ResultsUsing synchrotron micro-computer-tomography, we discovered in the arboreal frog Hyla cinerea that the ventral digital mucus glands differ in their morphology from regular anuran mucus glands and form a subdermal gland cluster. We show the presence of this gland cluster also in several other—not exclusively arboreal—anuran families. Using cryo-histochemistry as well as infrared and sum frequency generation spectroscopy on the mucus of two arboreal (H. cinerea and Osteopilus septentrionalis) and of two terrestrial, non-climbing frog species (Pyxicephalus adspersus and Ceratophrys cranwelli), we find neutral and acidic polysaccharides, and indications for proteinaceous and lipid-like mucus components. The mucus chemistry varies only little between dorsal and ventral digital mucus in H. cinerea, ventral digital and abdominal mucus in H. cinerea and O. septentrionalis, and between the ventral abdominal mucus of all four studied species.ConclusionsThe presence of a digital mucus gland cluster in various anuran families, as well as the absence of differences in the mucus chemistry between arboreal and non-arboreal frog species indicate an adaptation towards generic functional requirements as well as to attachment-related requirements. Overall, this study contributes to the understanding of the role of glands and their secretions in tree frog attachment and in bioadhesion in general, as well as the evolution of anurans.

Characterization of the bovine salivary gland transcriptome associated with Mycobacterium avium subsp. paratuberculosis experimental challenge

BackgroundMycobacterium avium subsp. paratuberculosis (MAP), the etiologic agent of Johne’s disease is spread between cattle via the fecal-oral route, yet the functional changes in the salivary gland associated with infection remain uncharacterized. In this study, we hypothesized that experimental challenge with MAP would induce stable changes in gene expression patterns in the salivary gland that may shed light on the mucosal immune response as well as the regional variation in immune capacity of this extensive gland. Holstein-Friesian cattle were euthanized 33 months’ post oral challenge with MAP strain CIT003 and both the parotid and mandibular salivary glands were collected from healthy control (n = 5) and MAP exposed cattle (n = 5) for histopathological and transcriptomic analysis.ResultsA total of 205, 21, 61, and 135 genes were significantly differentially expressed between control and MAP exposed cattle in dorsal mandibular (M1), ventral mandibular (M2), dorsal parotid (P1) and ventral parotid salivary glands (P2), respectively. Expression profiles varied between the structurally divergent parotid and mandibular gland sections which was also reflected in the enriched biological pathways identified. Changes in gene expression associated with MAP exposure were detected with significantly elevated expression of BoLA DR-ALPHA, BOLA-DRB3 and complement factors in MAP exposed cattle. In contrast, reduced expression of genes such as polymeric immunoglobin receptor (PIGR), TNFSF13, and the antimicrobial genes lactoferrin (LF) and lactoperoxidase (LPO) was detected in MAP exposed animals.ConclusionsThis first analysis of the transcriptomic profile of salivary glands in cattle adds an important layer to our understanding of salivary gland immune function. Transcriptomic changes associated with MAP exposure have been identified including reduced LF and LPO. These critical antimicrobial and immunoregulatory proteins are known to be secreted into saliva and their downregulation may contribute to disease susceptibility. Future work will focus on the validation of their expression levels in saliva from additional cattle of known infection status as a potential strategy to augment disease diagnosis.

A new soil centipede from South-East Asia with a unique arrangement of ventral glands, and a revised synopsis of Gonibregmatidae (Chilopoda, Geophilomorpha).

A new gonibregmatid centipede, Vinaphilusunicusgen. n., sp. n., is described based on two females from a single location in northern Vietnam. The new genus and species are distinguished mainly by the arrangement of the ventral pore-fields, which is unique among all Chilopoda. A critically revised synopsis of the Gonibregmatidae is also given. In particular, three species are provisionally recognized in Himatosoma Pocock, 1891: H.bidivisum Silvestri, 1919, H.porosum Pocock, 1891 (= H.typicumtridivisum Silvestri, 1919, syn. n.), and H.typicum Pocock, 1891. The genera Dschangelophilus Verhoeff, 1937 and Tweediphilus Verhoeff, 1937, with their species D.coloratus Verhoeff, 1937 and T.malaccanus Verhoeff, 1937, are moved to the Gonibregmatidae, whereas Geoporophilusaporus Attems, 1930 is moved to the Oryidae as Orphnaeusaporus (Attems, 1930), comb. n.

Accessory thyroid gland of the lateral neck

To the Editor, A 34-year-old Turkish woman presented with a left-sided cervical accessory thyroid gland. Her B-Mode thyroid ultrasonography exhibited an accessory thyroid parenchyma adjacent to the inferolateral border of left lobe of the thyroid gland (Figure 1a). fine-needle aspiration (FNA) cytology (FNAC) is a frequently used primary diagnostic procedure worldwide due to its preciseness, easiness, non-invasiveness, possessing very little complications and low cost [1, 2]. The thyroid gland ectopia and accessory thyroid tissue are two patterns of the abnormal thyroid gland migration. Ectopic thyroid gland is rare phenomenon and described as a functioning thyroid tissue in an aberrant area along the embryological descending line of the thyroid gland. Its most common form is known as lingual thyroid, accounting for 90 %. Aproximately 70 % of patients will exposed to the hormonal status of sub-clinical hypothyroidism [3]. These phenomenon may later undergo a malignant transformation [4]. An accessory thyroid gland is determined as a permanence of the thyroidal parenchyma anywhere from the base of the tongue to the thyroid isthmus, with the majority of the functional thyroid in its normal pre-tracheal area. The incidence of accessory thyroid gland is unknown [3]. Of 58 cadavers just one (1/58) was detected as the accessory thyroid gland on the thyroid cartilage by Braun et al [3]. Radkowski et al [5] performed thyroid US on 230 cases of the throglossal duct cyst and detected four cases (4/230) with the accessory thyroid tissue and three (3/230) with the ectopic thyroid gland. Therefore, they propunded the possibility of their equality in the incidence. The accessory thyroid glands are classified into five groups, based on their anatomical location: (1) cranial, (2) caudal, (3) lateral, (4) ventral, and (5) dorsal glands. They usually are founded along the former course of the thyroglossal duct and emigrate laterally [6]. Pyramidal lobes, superior accessory thyroids, retrotracheal, inferior/lateral extensions or extrusions are involved in the reasons of the recurrent thyroid diseases as the anomalies of the gland. Richards et al [3] asserted both thyroid gland ectopia and accessory thyroid tissue being vulnerable to the same potential diseases as a normally-situated thyroid gland. An accessory thyroid gland do not lead to clinical complication except in cases of the pathologic conditions such as goitre, malignancy, and the others. A thyroid FNA were planned, performed and its cytopathological evaluation with Haematoxylin and Eosin revealed a huge cellular cluster including the benign thyrocytes (Figure 1b). Therefore, a clinical follow-up was suggested for the present case, after a benign FNAC. Conclusively, education, training, and cognition of the thyroid anatomy and its associated variations and anomalies are very much essential for these kinds of the cases and it will lead to increasing the level of awareness.

Anatomic and magnetic resonance imaging features of the salivary glands in the dog.

The aim of the study was to describe the anatomical location and the topographic relationship of the major salivary glands to associated tissues in six dog cadavers by high-field magnetic resonance imaging (MRI) and gross anatomical dissections and sections. Spin-echo T1-weighted and T2-weighted magnetic resonance (MR) images were obtained in transverse, sagittal, and dorsal planes with a 1.5 T magnet. The digastric muscle, the external auditory canal, the eyeball, and the medial pterygoid muscle were the most consistent topographic landmarks for the identification of the mandibular, parotid, and zygomatic salivary glands, respectively. The best differentiation and contrast of the glands was observed in the T2-weighted images. In contrast with the osseous and muscular tissues, the salivary glands appeared hyperintense in greater or lesser measure except for the parotid gland, which displayed a hypointense signal. The rostral part of the monostomatic sublingual gland was precisely located between the tongue and the mylohyoid muscle. The best delineation between the caudal part of the monostomatic sublingual gland and the cranial aspect of the mandibular gland was observed in dorsal MRI at the level of the palate and the branches of the superior dental arcade. Good evaluation of the mandibular, parotid, caudal part of the monostomatic sublingual, zygomatic and buccal ventral glands was possible in sagittal MRI in close relation with the external auditory canal and the temporomandibular joint. The ventral buccal glands were also observed near the buccal vestibule as was the palatine glands within the soft palate.

Granuloma formation associated with the ventral submandibular scent glands of rabbits: a case series

Two entire male rabbits were presented with soft tissue thickening of areas on the ventral submandibular border of their chins. Subsequent imaging and further examination, including surgical investigation, ruled out bone or dental involvement, and surgical excision with concurrent castration was curative. Histopathology revealed granuloma formation, apocrine gland hyperplasia, and perivascular dermatitis, with, in one case, perihidradenitis and evidence of coagulative necrosis of apocrine glands with presumed secondary bacterial colonisation. No further lesions were noted at follow-up 24 months later in either case.