Histology, carbohydrate and protein histochemistry of the mandibular gland in suckling, prepuberal and puberal zebus (Bos indicus)

Histological, histometric and histochemical studies of the mandibular salivary glands of suckling, prepuberal and puberal zebu were carried out using 14 male animals. The developmental growth of this gland is characterized and correlated with histochemical development. These findings were correlated with other similar studies of Bovidae.     

Dacryops of the lacrimal gland in a dog

A case of congenital lacrimal cyst or dacryops of the lacrimal gland in an 8‐month‐old Neapolitan Mastiff dog is reported. The dog presented with a swelling dorsolateral to the left globe, which had been present since birth. In addition, hyperplasia and prolapse of the superficial gland of the left nictitating membrane, and bilateral macropalpebral fissure and ‘diamond eye’ conformation were apparent. On manual eversion of the upper eyelid, a subconjunctival mass was visible that was translucent and pink and affected the upper conjunctival fornix. B‐mode ultrasonography revealed the presence of an echolucent thin‐walled cystic structure measuring 15 by 12 mm and containing an echodense border and a distended tubular fluid‐filled structure that extended posteriorly. A viscous and transparent fluid was aspirated from the lesion. Surgery was performed to excise the lesion, reposition the nictitans gland, and correct the morphology of the palpebral fissure. Histopathology confirmed the mass to be a cyst and distended duct of the lacrimal gland. Although tear secretion was compromised, resection of the cyst was curative.     

Ultrastructural study of sheep lacrimal glands.

Sheep lacrimal glands are mixed glands, consisting of tubulo-acinar units succeeded by ducts of simple morphology. The secretory portions consist of three cell types: mucous, seromucous and serous, which may be intermingled in the same acinus or may form acini wholly made of only serous or mucous cells. Mucous cells show a rough endoplasmic reticulum that is reduced to a few cisternae located near the cell base and among the interstices of the secretory droplets. Mucous granules appear uniformly electron-lucent. Serous cells display a typical structure; serous granules can be uniformly electron-dense or composed of dense inclusions dispersed in an electron-lucent matrix. The seromucous granules have a bizonal substructure: a dense core is embedded in a highter matrix. Secretory acini are succeeded by intercalated ducts; the epithelium of these ducts gradually increases in height to form a kind of excretory duct, without the intervention of striated ducts.     

Morphology of lacrimal gland in pig fetuses

The morphological and histological examinations of the lacrimal gland were conducted on pig fetuses coming from the 20th, 24th, 27th, 30th, 35th, 50th, 63rd, 94th and 112th day of gestation. The morphological examinations were carried out using the method of macroscopic preparation with a forehead magnifying glass and binocular (magnification 1.5-5.0x). In order to better visualize the anatomical elements, 60-80% absolute alcohol and 0.5-4% acetic acid solution were used for the examinations. On the 20th, 24th, 27th, and 30th day of gestation the whole fetuses were collected for the histological examinations. The whole eyeball with developing accessory organs was collected from the pig fetuses on the 35th day of gestation. On the 50th, 63rd, 94th and 112th day of gestation only the lacrimal gland was collected. Staining with H-E and Azan method was performed. On the 20th, 24th, 27th, 30th and 35th day of gestation ectodermal cells were not found in the collected material. On the 50th and 63rd day of gestation the connective tissue divides the gland parenchyma into indistinct lobes composed of gland cells. On the 94th day of gestation the number of lobes is substantially higher than on the 50th and 63rd day of gestation, while the number of lobules forming lobes decreases. On the 112th day of gestation each lobe is composed of 8-22 excretory ducts made up of the simple cuboid epithelium with a round nucleus arranged less or more peripherally.     

Penetration of some antibiotics into the lacrimal fluid of sheep

Antibiotic concentrations were determined in the lacrimal fluid of sheep following subcutaneous application of penicillin/ dihydrostreptomycin into the lower eyelid, and intramuscular administration of spiramycin base, tiamulin, and oxytetracycline formulations. The penetration of penicillin and dihydrostreptomycin into the lacrimal fluid was poor. The spiramycin and tiamulin concentrations in the lacrimal fluid were 10‐ and 4‐fold higher than in the serum. The peak spiramycin concentration in the lacrimal fluid was 3.4 ±0.8 μg/ml at 8 h post injection (p.i.) and the drug could be detected at least 72 h p. i. For tiamulin and oxytetracycline (OTC) peak concentrations of 1.53 ±0.70 and 1.88 ±1.9 μg/ml, respectively, were achieved in the lacrimal fluid and these drugs could be detected 25 to 30 h p.i. The OTC and tiamulin concentration‐time curves for lacrimal fluid and serum were parallel, whereas for the spiramycin appearance in the lacrimal fluid was delayed.     

Histological and immunological studies on the fowl lacrimal gland following surgical excision of Harder's gland.

Surgical removal of the Harderian gland of the domestic fowl resulted in increased secretory activity in the lacrimal gland and also in an increase in goblet cell numbers along the length of the lacrimal gland duct. Plasma cells were more numerous in the lacrimal glands of operated birds and they were capable of antibody responses to both systemically and topically applied bovine serum albumin (BSA). Gel diffusion studies showed the presence of anti-BSA activity in the tears and serum of fowls stimulated after surgical removal of the Harderian gland.     

A pleomorphic adenoma of the lacrimal gland in a dog

A 13-year-old female mongrel dog had a pleomorphic adenoma of the lacrimal gland in the right upper orbit. The tumor measured 3.8 x 3.0 x 3.3 cm, appeared white, round, and firm, and pressed the right globe and surrounding tissues. Histopathologically, the tumor had a thin connective tissue capsule and was composed of tubules with two cell types, some resembling luminal epithelial cells making up the tubular structures and the other of myoepithelial cells. Epithelial tubules were disposed in an adenomatous fashion and separated from each other by proliferating pleomorphic myoepithelial cells. Immunohistochemically, large numbers of the luminal epithelial cells revealed an immunopositive reaction against keratin/cytokeratin (AE1/AE3), and some epithelial cells reacted against cytokeratin 14. Spindle-shaped myoepithelial cells revealed an immunopositive reaction against cytokeratin 14, alpha-smooth muscle actin, and vimentin. A small number of myoepithelial cells reacted against desmin. S-100 protein immunopositivity was frequently found in luminal epithelial cells and rarely in the pleomorphic myoepithelial cells. Glial fibrillary acidic protein positivity was commonly found in myoepithelial cells, myxoid matrices, and intracystic materials, but not in luminal epithelial cells.     

Primary lacrimal gland adenocarcinoma of the third eyelid in a horse

A 5-year-old Draft Horse gelding presented for evaluation of a large, fleshy, ulcerated third eyelid mass OD of 3 weeks duration. Complete ophthalmic examination, ocular ultrasound and skull radiographs revealed a large soft-tissue mass involving the entire third eyelid OD and extending into the ventral right orbit to the level of the globe equator. No other abnormalities were noted on physical or ophthalmic examination. Surgical removal via exenteration was performed 3 months after initial presentation. A lacrimal adenocarcinoma of the third eyelid was diagnosed based on histopathology. Concurrent asymptomatic intra-ductal and intra-acinar Demodex caballi parasites were found in the eyelid sebaceous glands, likely as an incidental finding. No tumor recurrence or metastasis has occurred 12 months after excision. To the author's knowledge, this case is the first reported primary lacrimal adenocarcinoma in a horse. Complete surgical excision was curative.     

Prenatal growth of the adrenal gland in sheep

From 1256 adult sheep received for clinical/post-mortem examination over an 8 1/2-year period, intestinal adenocarcinomas were diagnosed in 37 (2.9%). Mean age of the affected animals was 6.1 years. Clinical pathology and post-mortem findings are summarized.     

Localization of the sheep FcRn in the mammary gland

Among the multiple functions, which have been identified for the neonatal Fc receptor (FcRn), we study its role in the IgG transport in the mammary gland during the colostrum formation. For this reason, we have obtained several mammary gland biopsies from a pregnant sheep around parturition. The presence of the FcRn heavy chain mRNA was detected exclusively in the acinar and ductal epithelial cell by in situ hybridization (ISH). We detected strong signal in samples harvested 24 and 10 days prepartum; however, in samples we collected postpartum was barely detectable. Immunohistochemistry confirmed our ISH data. The cytoplasm of the epithelial cells of the acini and ducts in the mammary gland biopsies stained homogeneously before parturition, although a remarkable difference was observed in the pattern after lambing. The signal indicated uneven distribution of the FcRn alpha chain in the epithelial cells 1 and 5 days postpartum, since the apical sides of the epithelial cells were highlighted. The presence of the FcRn in the acinar and ductal epithelial cells and the obvious change of its distribution before and after parturition suggest that FcRn plays an important role in the IgG transport during colostrum formation. FcRn expression was also found in the lamb duodenal crypt epithelial cells, which have been previously demonstrated to secrete IgG1 in newborn ruminants, suggesting secretory role of the FcRn in ruminant epithelial cells.     

Clinical and ultrasonographic findings in the mammary gland of sheep

AIM: To compare clinical and ultrasonographic findings and assess the value of ultrasonography for evaluating the structure and condition of the teat and teat canal of sheep. METHODS: The mammary glands of 30 lactating ewes were examined clinically and using ultrasonography. The distance from the teat tip to the ground was measured and diagnostic images of the body of the gland, gland cistern and teat cistern were obtained using an 8.5 MHz frequency ultrasonic transducer. A California mastitis test (CMT) and bacteriological culture were performed on milk samples collected from each half of each udder. RESULTS: Udder parenchyma and teats were palpably normal in 27/30 (90%) ewes. Milk clots or abnormalities were evident in 4/30 (13%) udders, lesions in the glandular parenchyma and/or teats were evident by palpation in 3/30 (10%), and pathogenic bacteria were cultured from 2/30 (7%). In both of the latter cases, mastitis was diagnosed based on clotted and discoloured appearance of milk and highly positive CMT reactions. Ultrasonographic examination in these udders revealed non-homogenous regions in the glandular tissue and alternating areas of hyperechogenic and hypoechogenic tissue. Overall, highly positive CMT reactions were evident in milk from 14/30 (47%) left halves and 9/30 (30%) right halves (p=0.02). No relationship between teat-to-ground distances and CMT results was evident (p>0.05). Teat canal lengths ranged from 5.7-10.3 mm (mean=8.6; SD=1.3 mm) and the widths from 1.8-3.1 mm (mean=2.3; SD=0.4 mm). Milk sampled from ewes that had long (> or = 9 mm) or wide (> or = 2 mm) teat canals was highly positive to the CMT in 75% and 83% of cases, respectively. CONCLUSIONS: Ultrasonographic measurements of the length and width of the teat canal appeared to correlate with CMT results. The use of ultrasonography in evaluating the health of the udder of small ruminants holds promise for the future.     

Localization of glycoconjugates in dog parotid gland by lectin histochemistry

Parotid glands from adult dogs were stained with a battery of seven horseradish peroxidase-conjugated lectins (PNA, UEA, LTA, DBA, SBA, WGA and ConA). In some cases (PNA and DBA) neuraminidase digestion was followed by lectin staining. Acinar cells contained conspicuous quantities of oligosaccharides with terminal sialic acid radicals. Galactosil-(13)N-acetylgalactosamine was the most abundant penultimate sugar linked toN-acetylneuraminic acid. Sialylated components having the terminal dimer sialic acid-N-acetylgalactosamine were found in the acinar cells. Secretory cells presented a heterogeneous distribution of glycoconjugates with terminal fucose and -N-acetylgalactosamine. Fucose,N-acetylglucosamine and -N-acetylgalactosamine were present on the apical cytoplasm and surface of the striated and interlobular duct cells. This glycosidic composition was unaffected by extensive selective breeding. The role of abundant amounts of sialic acid radicals in the oral mucosa was considered.Abbreviations HRP horseradish peroxidase - PBS phosphate-buffered saline see also Tables I and III     

Clinical and ultrasonographic findings in the mammary gland of sheep

AIM: To compare clinical and ultrasonographic findings and assess the value of ultrasonography for evaluating the structure and condition of the teat and teat canal of sheep.

METHODS: The mammary glands of 30 lactating ewes were examined clinically and using ultrasonography. The distance from the teat tip to the ground was measured and diagnostic images of the body of the gland, gland cistern and teat cistern were obtained using an 8.5 MHz frequency ultrasonic transducer. A California mastitis test (CMT) and bacteriological culture were performed on milk samples collected from each half of each udder.

RESULTS: Udder parenchyma and teats were palpably normal in 27/30 (90%) ewes. Milk clots or abnormalities were evident in 4/30 (13%) udders, lesions in the glandular parenchyma and/or teats were evident by palpation in 3/30 (10%), and pathogenic bacteria were cultured from 2/30 (7%). In both of the latter cases, mastitis was diagnosed based on clotted and discoloured appearance of milk and highly positive CMT reactions. Ultrasonographic examination in these udders revealed non-homogenous regions in the glandular tissue and alternating areas of hyperechogenic and hypoechogenic tissue. Overall, highly positive CMT reactions were evident in milk from 14/30 (47%) left halves and 9/30 (30%) right halves (p=0.02). No relationship between teat-to-ground distances and CMT results was evident (p>0.05). Teat canal lengths ranged from 5.7–10.3 mm (mean=8.6; SD=1.3 mm) and the widths from 1.8–3.1 mm (mean=2.3; SD=0.4 mm). Milk sampled from ewes that had long (≥9 mm) or wide (≥2 mm) teat canals was highly positive to the CMT in 75% and 83% of cases, respectively.

CONCLUSIONS: Ultrasonographic measurements of the length and width of the teat canal appeared to correlate with CMT results. The use of ultrasonography in evaluating the health of the udder of small ruminants holds promise for the future.     

Arterial supply of the pineal gland of Akkaraman sheep

Arterial vascularisation of the ovine pineal gland was investigated by latex injection preparations of the common carotid artery in 20 adult Akkaraman sheep brains under stereo light microscope. It was observed that the arterial supply comes exclusively from branches of the caudal cerebral artery. The pineal gland was found to contain a rich vascular network. This network also received a few branches from the caudal choroid rami.     

Orbital adenocarcinoma of lacrimal gland origin in a dog.

A 13-year-old intact female mixed-breed dog was presented for a progressive enlargement of the right eye, which had been treated previously for conjunctivitis. A round, firm mass, approximately 4 cm in diameter, was protruding from the superotemporal aspect of the right orbit, displacing the eyeball anteriorly and ventromedially. The mass was encapsulated, distinct from the eyeball, and not associated with the eyelids. On cut surface, there was a pale multilobulated periphery, with a dark red, soft, and depressed core. Histologically, tumor cells formed cords and tubules, which were stained with mouse anti-human cytokeratin antibody AE1/AE3. Residual glands were serous, and the majority of tumor cells were negative for mucin. The supraorbital location, encapsulation, and residual serous glands suggest that this mass was a low-grade adenocarcinoma of the lacrimal gland.