Gland Of Goats Research Articles

Pharmacokinetics of Doxycycline in Plasma and Milk after Intravenous and Intramuscular Administration in Dairy Goats.

Doxycycline is a second-generation tetracycline, marketed in different species for treating infections caused by susceptible bacteria. Little information is available on the pharmacokinetics of doxycycline in lactating goats. The objective of this study was to establish the disposition kinetics of doxycycline after parenteral administration (intravenous and intramuscular) in dairy goats and its elimination in milk. A cross-over model was designed (n = 6). Doxycycline was dosed at 5 mg/kg for intravenous administration and 20 mg/kg for extravascular administrations. Noncompartmental pharmacokinetic methods were used to calculate plasma concentration-time data. The Vz value suggests a moderate distribution of this antibiotic in goats, with a value of 0.85 L/kg. A low bioavailability (F = 45.60%) of doxycycline following an intramuscular injection was observed, with all animals exhibiting signs of lameness. Doxycycline rapidly crossed the blood-milk barrier, but exposure to the antimicrobial and the concentrations reached in milk were lower than those obtained in plasma. Although PK/PD ratios may be low with the pharmacokinetic data obtained with this formulation of doxycycline, at this dose and route of administration, doxycycline after IM administration could be useful for infections by moderate or highly susceptible bacteria in the mammary gland of goats. However, it may be necessary to test different doses of doxycycline or other routes of administration to achieve better surrogate markers and to establish repeated dosing regimens and clinical efficacy.

Biometric and ultrasonographic evaluation on mammary gland of goat

Gross and ultrasonographic studies were conducted on the mammary gland of goat (n=18 for each study) during pre-pubertal, lactating and non-lactating stages. Mammary gland was located into the inguinal region and divided into two halves by mammary groove which was prominent during lactation stage. Each halve had separate glandular body and conical teat divisible into tip, mid and base regions. The mammary gland contained numerous lactiferous ducts which opened into the gland sinus that continued distally as teat sinus and teat canal. The gland sinus and teat sinus were separated from each other by annular folds, which were more prominent in lactating animals. At the junction of teat sinus and teat canal, small mucosal elevation was observed as Furstenberg’s rosette. Teat wall was lined by skin, teat internal mucosal layer and teat sinus from outside to inside. Ultrasonographic observations showed that the lactating mammary gland contained an echogenic structure of variable size indicating gland sinus, lactiferous ducts, blood vessels, glandular parenchyma, while the homogenous echogenic component depicting more connective tissue stroma in non-lactating and pre-pubertal goat. The teat wall was made up of innermost hyperechogenic layer (teat mucosa), middle hypoechogenic (fibromuscular) layer and mild hyperechogenic teat skin. Teat sinus was anechogenic, however teat canal was demarcated by hyperechogenic streak. Biometrical and ultrasonographic observations were recorded on teat canal length, maximum diameter of teat, maximum teat wall thickness. Present study showed that there was no significant difference in biometric and ultrasonographic measurements of goat teat. Therefore, it may be concluded that the gross and ultrasonographic observations may be used to diagnose any abnormality in the udder during clinical examination.

Effect of repeated intrauterine infusion of lipopolysaccharides on mastitis in goats

A single infusion of lipopolysaccharide (LPSs) into the uterus induces inflammation in the mammary gland. This indicates that LPS can translocate from the uterus to the mammary gland. Natural endometritis is characterized by continuous intrauterine inflammation. The aim of the present study was to determine the effect of repeated intrauterine infusion of two different types of LPSs obtained from Escherichia coli O111:B4 (LPS-O111) and O55:B5 (LPS-O55) on the inflammatory status of the mammary glands of goats. Goats were assigned to three groups: LPS-O111, LPS-O55, and saline (control). Saline with (LPS-O111 and 55 groups) and without (control) 100 μg LPS was infused into the uterus continuously for 7 days. Decreased milk yield was detected in both LPS-O111 and LPS-O55 groups 2 days after the first LPS infusion. While somatic cell count (SCC) was significantly increased in all groups 1 day after the first LPS infusion, both LPS infusions further increased SCC 2 days after the first infusion and showed a significantly higher SCC than that in the control group. Plasma LPS-binding protein (LBP) was significantly higher in both LPS groups than in the control group during the days after infusion. In addition, pro-inflammatory cytokines, interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and IL-8, were significantly increased in both LPS infusion groups compared with those in the control group. The LPS-O111 infusion resulted in higher SCC, LBP, TNF-α, and IL-8 concentrations than those in the LPS-O55 group. These results suggest that repeated LPS infusion into the uterus can induce more severe mammary gland inflammation than a single infusion. Interestingly, the mammary tissues recovered from inflammation even though the LPS intrauterine infusion was continued.

Genome-wide analysis of the acyl-coenzyme A synthetase family and their association with the formation of goat milk flavour.

Goat milk is rich in fat and protein, thus, has high nutritional values and benefits human health. However, goaty flavour is a major concern that interferes with consumer acceptability of goat milk and the 4-alkyl-branched-chain fatty acids (vBCFAs) are the major substances relevant to the goaty flavour in goat milk. Previous research reported that the acyl-coenzyme A synthetases (ACSs) play a key role in the activation of fatty acids, which is a prerequisite for fatty acids entering anabolic and catabolic processes and highly involved in the regulation of vBCFAs metabolism. Although ACS genes have been identified in humans and mice, they have not been systematically characterized in goats. In this research, we performed genome-wide characterization of the ACS genes in goats, identifying that a total of 25 ACS genes (without ACSM2A) were obtained in the Capra hircus and each ACS protein contained the conserved AMP-binding domain. Phylogenetic analysis showed that out of the 25 genes, 21 belonged to the ACSS, ACSM, ACSL, ACSVL, and ACSBG subfamilies. However, AACS, AASDH, ACSF, and ACSF3 genes were not classified in the common evolutionary branch and belonged to the ACS superfamily. The genes in the same clade had similar conserved structures, motifs and protein domains. The expression analysis showed that the majority of ACS genes were expressed in multi tissues. The comparative analysis of expression patterns in non-lactation and lactation mammary glands of goat, sheep and cow indicated that ACSS2 and ACSF3 genes may participate in the formation mechanisms of goaty flavour in goat milk. In conclusion, current research provides important genomic resources and expression information for ACSs in goats, which will support further research on investigating the formation mechanisms of the goaty flavour in goat milk.

Characterization of the microRNA Expression Profiles in the Goat Kid Liver.

The liver is the largest digestive gland in goats with an important role in early metabolic function development. MicroRNAs (miRNA) are crucial for regulating the development and metabolism in the goat liver. In the study, we sequenced the miRNAs in the liver tissues of the goat kid to further research their regulation roles in early liver development. The liver tissues were procured at 5-time points from the Laiwu black goats of 1 day (D1), 2 weeks (W2), 4 weeks (W4), 8 weeks (W8), and 12 weeks (W12) after birth, respectively with five goats per time point, for a total of 25 goats. Our study identified 214 differential expression miRNAs, and the expression patterns of 15 randomly selected miRNAs were examined among all five age groups. The Gene ontology annotation results showed that differential expression miRNA (DE miRNA) target genes were significantly enriched in the fatty acid synthase activity, toxin metabolic process, cell surface, and antibiotic metabolic process. The KEGG analysis result was significantly enriched in steroid hormone synthesis and retinol metabolism pathways. Further miRNA-mRNA regulation network analysis reveals 9 differently expressed miRNA with important regulation roles. Overall, the DE miRNAs were mainly involved in liver development, lipid metabolism, toxin related metabolism-related biological process, and pathways. Our results provide new information about the molecular mechanisms and pathways in the goat kid liver development.

Local Heat Treatment of Goat Udders Influences Innate Immune Functions in Mammary Glands.

Heat stress and mastitis adversely affect milk production in dairy ruminants. Although the udder temperature is elevated in both conditions, the influence of this local temperature rise on milk production and immune function of ruminant mammary glands remains unclear. To address this question, we heated the mammary glands of goats by covering one half of the udder with a disposable heating pad for 24h, the other uncovered half served as a control. Sixteen Tokara goats (1-5 parity) and three Shiba goats (1-2 parity) at the mid-lactation stage were individually housed, fed 0.6kg of hay cubes and 0.2kg of barley per day, and had free access to water and trace-mineralized salt blocks. Milk samples were collected every 6h for 24h after covering (n = 16), and deep mammary gland tissue areas were collected after 24h (n = 5). The concentrations of antimicrobial components [lactoferrin, β-defensin-1, cathelicidin-2, cathelicidin-7, and immunoglobulin A (IgA)] in milk were measured by the enzyme-linked immunosorbent assay (ELISA). The localization of IgA was examined by immunohistochemistry. The mRNA expression and protein concentrations of C-C motif chemokine ligand-28 (CCL-28) and interleukin (IL)-8 in the mammary gland tissue were measured using quantitative polymerase chain reaction and ELISA, respectively. The somatic cell count in milk was significantly higher in the local heat-treatment group than in the control group after 12h of treatment. The treatment group had significantly higher concentrations of cathelicidin-2 and IgA than the control group after 24h of treatment. In addition, the number of IgA-positive cells in the mammary stromal region and the concentration of CCL-28 in the mammary glands were increased by local heat treatment. In conclusion, a local rise in udder temperature enhanced the innate immune function in mammary glands by increasing antimicrobial components.

CT appearance and measurements of the normal thyroid gland in goats

BackgroundGoats are increasingly being kept as companion animals, thus their owners expect advanced medical care, including modern diagnostic imaging. Computed tomography (CT) is now widely used in veterinary medicine, in both clinical practice and for scientific purposes. So far, the CT appearance of various body parts has been described in goats, but reports on thyroid gland CT are still lacking. The thyroid gland in goats may become enlarged due to dietary, genetic or neoplastic disorders. CT examination, as in other animals and humans, could aid in the diagnosis of thyroid diseases in goats and could be used for research purposes. The aim of the study was to present the CT characteristics of the normal caprine thyroid gland, in particular its dimensions, volume and density.ResultsFifty-seven goats were included in the study. None of the animals had clinical, CT, post-mortem or histopathologic abnormalities in the thyroid gland. CT features of the thyroid gland were determined, such as dimensions, volume, density, location and shape. The presence of the thyroid isthmus and ectopic thyroid tissue was also assessed. The gland was visible in every animal as two homogenous, highly attenuating, well-circumscribed lobes located in the most cranial part of the trachea. The mean dimensions of the thyroid lobe were 30.3 × 12.7 × 6.7 mm, the mean density was 80.9 Hounsfield Units (HU) and the mean volume was 1.32 cm3 or 1.39 cm3, depending on the method used. Also, the internal parathyroid glands were visible in some animals.ConclusionsFor the first time, the normal CT appearance of the thyroid gland has been presented. CT clearly shows the thyroid gland in goats and therefore can be used in clinical practice and for research. The results of the current study may serve as a radiological guideline for practitioners and may be the basis for further CT studies on normal and diseased caprine thyroid glands.

Composition and Therapeutic Applications of Goat Milk and Colostrum

Goats are categorized under the small ruminants which required less fodder and a small area for shelter. Both goat milk (GM) and colostrum (GC) are secreted from the mammary glands of goats. The level of nutritional and bioactive components found to be at an elevated level in colostrum within 72 hours, which reach a normal level as the time increases from parturition. Recently an increased interest in goat milk and colostrum has been seen throughout the world due to the natural exitance of vital components including immunoglobins, growth factors, hormones, lactoferrin, and lysozyme. The compositional parameter of both GM and GC is significantly altered by genetic and environmental factors. The sialic acid is a prime component of goat colostrum which assists in brain development. The small size fat globules of goat milk make it more tolerable and digestible as compared to other milk sources. GM is composed of low level of lactose which can be consumed easily by lactose-intolerant individuals. Different GM and GC-based products viz yogurt, ice cream, infants’ formulas are prepared and commercialized globally. The nutritional components of GM and GC improve overall body growth and development. Where the bioactive components are clinically proven in the prevention and pre-treatment of numerous chronic diseases.

Infectious and Non-infectious Factors Affecting Somatic Cell Count and New Diagnostic Approaches of Intramammary Infections in Dairy Goats: A Review

Background: Intramammary infections constitute major animal health and economic problem in commercial dairy goat farms, being responsible for decreases in milk yield, alter milk composition, and lower milk quality. Objectives: This paper reviews the published literature during the last three decades, highlighting the multiplicity of non-infectious and infectious factors that influence somatic cell count (SCC). Besides that, it intends to contribute to understanding the conventional diagnostic methods and their limitations, and supports the implementation of new technologies for efficient mastitis control, including the use of infrared thermography and ultrasonography. Methods: A search on Medline, ScienceDirect, and University Institutional Repositories databases was performed using “goats, AND mastitis OR intramammary infections OR somatic cells count” for publications from 1990 to present (2020). Results: A total of 144 publications were selected. The SCC is the most important criteria to evaluate the inflammatory status of the mammary glands in goats, but several non-infectious factors (e.g., phenotypic, reproductive, lactational factors) should be taken into consideration for its interpretation. Bacteria and fungi as well as lentivirus are commonly responsive for intramammary infections. Intermittent secretion or environmental contamination of milk pathogens, costs, and time delay poses challenges using conventional diagnostic methods. Ultrasonographic and thermographic techniques applied to the udder seem to be of diagnostic value in acute and chronic mastitis. Conclusions: Unlike other ruminants species, non-infectious factors have a major impact on SCC which should be taken in account for mastitis diagnosis, and according to milk pathogens detection. Further research in imagological techniques is needed to accurately contribute to implant new mastitis control strategies.

Differentially Expressed MiRNAs of Goat Submandibular Glands Among Three Developmental Stages Are Involved in Immune Functions.

Submandibular glands (SMGs) are one of the primary components of salivary glands in goats. The proteins and biologically active substances secreted by the SMGs change with growth and development. Our previous studies showed that most of the differentially expressed genes in the SMGs of goats at different developmental stages are involved in immune-related signaling pathways, but the miRNA expression patterns in the same tissues are unknown. The aim of this study was to reveal the expression profile of miRNAs at three different developmental stages, detect differentially expressed miRNAs (DE miRNAs) and predict disease-related DE miRNAs. SMG tissue samples were collected from groups of 1-month-old kids, 12-month-old maiden goats and 24-month-old adult goats (three samples from each group), and high-throughout transcriptome sequencing was conducted. A total of 178, 241 and 7 DE miRNAs were discovered between 1-month-old kids and 12-month-old maiden goats, between 1-month-old kids and 24-month-old adult goats, and between 12-month-old maiden goats and 24-month-old adult goats, respectively. Among these DE miRNAs, 88 DE miRNAs with medium or high expression levels (TPM ≥50) were classified into five expression pattern clusters. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses indicated that some of the predicted target genes of the DE miRNAs in the five clusters were enriched in disease-related GO terms and pathways. MiRNA target genes in significant pathways were significantly enriched in Hepatitis B (FDR = 9.03E-10) and Pathways in cancer (FDR = 4.2E-10). Further analysis was performed with a PPI network, and 10 miRNAs were predicted to play an important role in the occurrence and prevention of diseases during the growth and development of goats.

Nervous-hormonal regulation of protein secretion by the mammary gland in goats

Nervous-hormonal regulation of protein secretion by the mammary gland in goats

Neoplasms of the thyroid gland in goats (Capra hircus) - A slaughterhouse based study

Neoplasms of the thyroid gland in goats (Capra hircus) - A slaughterhouse based study

Evaluation of pro- and anti-inflammatory interleukins in the mammary gland of goats experimentally infected with Staphylococcus chromogenes.

The aim of this work was to evaluate the relative gene expression levels of the cytokines IL- 1B, IL-8, IL-12, IFN-γ, IL-4, IL-10 and TGF-β in somatic milk cells of French Alpine breed, anestrous goats that were experimentally infected in the left mammary gland with Staphylococcus chromogenes during the lactation peak. Milk samples were obtained from both glands for 21 consecutive days post infection. Total RNA was extracted, and real-time PCR was conducted using primers specific to each cytokine. The relative RNA expression of the evaluated cytokines was determined by the comparative method 2-ΔΔCT, using milk from the right gland of the goats as a reference (control) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as an endogenous control. According to the Wilcoxon test results, IL-1B and IL-12 expression levels showed significant differences compared to those in the control group (p⟨0.05) from 24 hours post infection until the end of lactation; on day three, IL1β, IL8, IL12 and TGF-β had a statistically significant change in expression with respect to those in the control group (p⟨0.05); closer to the end of the lactation period, there is no overexpression of the anti-inflammatory interleukins (IL-4 and TGF-β) which may reflect the effort of the host immune system to eradicate the microorganism from the mammary gland.

Genetic parameters of weeping teats in Italian Saanen and Alpine dairy goats and their relationship with milk production and somatic cell score

This paper reports a quantitative genetics analysis of weeping teats (WT), an abnormality of the mammary gland in goats. Weeping teats are characterized by milk oozing out of the teat or by the presence of multiple cysts near its base. This abnormality has been routinely recorded in Italian Alpine and Saanen goats since 2000 using a score of 0 or 1 (0 = defect not present, 1 = defect present). No information is available on the genetic background of WT or its relationship with production or other udder-related traits. Data obtained by the Italian National Sheep and Goat Breeders Association (Rome, Italy) were used to estimate both heritability of WT and its genetic correlation with milk yield, somatic cell score, and udder traits. The final data set used in the analysis included 2,178 Saanen and 2,309 Alpine primiparous goats kidding from 2009 to 2014. The pedigree data included 7,333 Saanen and 7,421 Alpines, respectively. A threshold-linear multivariate animal model was used to estimate variance and covariance components. A genealogical data analysis was also implemented, including genealogical data completeness, inbreeding, and identification of possible most recent common ancestors. On average, around 4 and 13% of primiparous Saanen and Alpine females kidding from 2009 to 2014 showed mammary gland abnormality, respectively. Weeping teats heritability was 0.27 and 0.26 for Saanen and Alpine, respectively. Genetic correlations between milk production or somatic cell score ranged from -0.16 in Saanen to 0.43 in Alpine, but the standard error of the estimates was very large. Positive genetic correlations were observed among WT and teat characteristics in both Saanen and Alpine. The average inbreeding of abnormality carriers was 2.4 and 5.1 for Saanen and Alpine, respectively. The genealogical data analysis identified 4 common ancestors of affected does in Saanen and 2 in Alpine. These results indicate that WT have a possible genetic background. A genome-wide association study might help in understanding the polygenic or monogenic determination of this abnormality.

Ultrasonographic and anatomical examination of normal thyroid and internal parathyroid glands in goats.

Ultrasonographic examination of the normal thyroid and parathyroid glands has been described for humans and many animal species. However, similar reports for goats are still missing. The aim of the study was to present ultrasound features of the normal thyroid and internal parathyroid glands in goats with the determination of their dimensions and volume, followed by a comparison of the results to the gross examination. Seventy-two goats were used in the study. The echostructure and echogenicity of the thyroid and parathyroid glands were assessed. The length, width and height of the thyroid and the length and width of the parathyroid glands were measured. The thyroid volume was calculated using the ellipsoid formula, basing on the ultrasonographic dimensions. Size and volume of the dissected thyroid glands were established grossly, followed by a histological examination. In order to accurately describe the anatomy of the thyroid, new anatomical terminology characterizing this gland was proposed. The mean dimensions of the thyroid lobes were 30.2 x 10.5 x 6.3 mm. There were no statistically significant differences between the right and left lobe. Parathyroid glands measured an average of 3.6 x 2.4 mm. The percentage Root Mean Square Error between the results of ultrasonographic and gross examination was 16.73%, 20.65% and 17.01% for thyroid length, width and height, respectively, and 46.30% for volume. In order to obtain more precise calculation of the thyroid volume, a modified correction factor for the ellipsoid formula was introduced. For the first time, the normal ultrasonographic characteristics and dimensions of the caprine thyroid and internal parathyroid glands were presented. The results may serve as a radiological reference and be the basis for further research.

An Overview of Specific Pathogens in Goat Mastitis

Goat milk ranks fourth in terms of global milk production and lately it has become increasingly popular among consumers. Unfortunately, mastitis is one of the most common diseases that affects dairy goats, with serious economic consequences and food safety matters. The prevalence of clinical mastitis is lower than 5% and the main aetiological agent is S. aureus. On the other hand, the prevalence of subclinical mastitis is between 5-30%, with coagulase negative staphylococci (CNS) representing the most often isolated microorganisms.The aim of this paper is to highlight the main aspects regarding the aetiology of goat mastitis, as well as the importance of the milk somatic cell count (MSCC) in the diagnosis process. Although the inflammation of the mammary gland in goats is not as frequently diagnosed compared to cow mastitis, there are several aspects worth discussing in order to fully understand the pathogenesis of intramammary infections.

Efficacy of sodium butyrate in alleviating mammary oxidative stress induced by sub-acute ruminal acidosis in lactating goats

Sub-acute ruminal acidosis (SARA) [1] is one of the most common problems of dairy animals causing great economical loss due to decreased milk production. Here we determined the antioxidant effect of sodium butyrate (NaB) [2] in experimentally induced SARA and its effects on mammary epithelial tissues of goat. Goats (n = 12) were equally divided into two groups: high-concentrate (HC) as control group fed with HC diet (concentrate: forage = 6:4) whereas HC + NaB as treatment group fed HC diet with NaB at 1% by weight for 24 weeks. Mammary epithelial tissue samples were analyzed for the expression of genes and proteins responsible for oxidative stress as well as biochemical markers of antioxidant activity in the form of Reactive Oxygen Species (ROS). The total antioxidant capacity (T-AOC) of antioxidant enzymes was also calculated. Butyrate induced antioxidant effect by increasing mRNA and protein abundance of antioxidants in mammary gland of HC + NaB group compared to HC group. Likewise, the total antioxidant capacity (T-AOC) was significantly increased and Malondialdehyde (MDA) concentration was decreased in HC + NaB group compared to HC group. It is concluded that oxidative stress in mammary gland of goats induced by high concentrate diet was alleviated by NaB supplementation.

Gross and Histological Studies of Lacrimal Gland in Goats (Capra hircus )

Gross and Histological Studies of Lacrimal Gland in Goats (Capra hircus )

MORPHOLOGICAL AND HISTOLOGICAL STUDIES ON PARATHYROID GLAND OF ADULT MALE GOAT (CAPRA HIRCUS)

The parathyroid glands are essential endocrine glands as they produce hormones that maintain calcium within the normal level in blood through secretion of parathormone. The removal of parathyroid glands leads to fatal levels of hypocalcemia. The number of parathyroid glands is species specific. The current investigation was performed on 20 healthy freshly slaughtered adult male goats. Fifteen specimens were immediately fixed in 10% buffered neutral formalin, then processed for histological and immunohistochemical examination. Other 5 specimens were handled for transmission electron microscope. The present work was conducted to study the morphological and histological characteristics of parathyroid glands of goat. Parathyroid glands comprised of two pairs, each pair formed from external and internal glands. External parathyroid gland was rounded or oval in shape. Its location was varied in the same animal where it may be located cranial to thyroid gland or beside the submandibular salivary gland. Internal parathyroid gland was embedded inside thyroid tissue. It appeared as pale rounded area at the end of cranial part of the right and left thyroid lobe. The histological findings demonstrated that, each parathyroid gland is surrounded by a thin capsule of dense irregular connective tissue. The glandular parenchyma is divided by short thick septa into ill distinct compartments. Each compartment had numerous numbers of chief cells. The active chief cells were polygonal in shape with oval nuclei. Immuno-histochemical findings revealed that they are positively reacted against chromogranin antibody. Electron microscope revealed that the cytoplasm have abundant mitochondria, rough endoplasmic reticulum, evenly distributed golgi apparatus and numerous secretory granules. On the contrary, the inactive chief cells have more vacuolated cytoplasm which contains less cell organelles.

Ultrastructure and immunohistochemical characterization of proteins concerned with the secretory machinery in goat ceruminous glands.

The expression of soluble N-ethylmaleimide sensitive fusion attachment protein receptor (SNARE) proteins in apocrine glands has not been fully elucidated. In addition to performing ultrastructural observation of the ceruminous glands in goats, our study focuses on the demonstration of β-defensins, SNARE proteins and Rab3D in these glands with the use of immunohistochemical methods. The secretory cells were equipped with two types of vesicles, Golgi apparatus and abundant rough endoplasmic reticulum (ER). Additionally, in some of them, the characteristic concentric structures composed of rough ER were observed in their circum- and infranuclear parts. The expression of phosphorylated inositol requiring enzyme 1rrwas also detected. These findings may indicate their ability to produce numerous secretory proteins and the maintenance of homeostasis in the glandular cells. Furthermore, β-defensins were demonstrated as products of the ceruminous glands. The present investigation also revealed the presence of SNARE proteins and Rab3D. It is suggested that these proteins are concerned with the secretory machinery of this gland type.