Thumbnail Image

Theses

Browse

2005 - 20103
Reset filters
Subject: Veterinary Anatomy × Author: KAU × Start date: 2000 × Type: Thesis ×
Reset filters

Search Results

Now showing 1 - 3 of 3
  • Thumbnail Image
    ThesisItemOpen Access
    Post-hatch development of preen gland in the duck (anas platyrhynchos)
    (Department of Anatomy, College of Veterinary and Animal Sciences, Mannuthy, 2005) Rajathi, S; KAU; Ashok, N
    The study on the post-hatch development of the preen gland in ducks was conducted using 44 ducks from the day of hatch to 150 days of age. The project was taken up to trace the structure and development of the glands and their relationship with the age and body weight. After recording gross relations and measurements, the material was fixed using various fixatives for studying the cellular details, arrangement of cells, connective tissue framework, micrometry and histochemistry. The preen gland was a paired organ with two gland and a common cylindrical papilla together formed a ‘V’ shaped structure. Each gland was pear shaped and pale yellow in colour, in fresh state. They were located on the dorsal surface of the pygostyle. The two glands had separate ducts. The uropygial circlet was seen at the tip of the papilla. The glands were vascularized through a pair of branches from the caudal artery and innnervated through the medial caudal nerve. The weight of the preen glands increased progressively from the day of hatch to 150 days of age. This weight was positively correlated with the age and body weight. The proportion of the gland weight to body weight showed a decreasing trend. The right gland was slightly heavier, longer, wider and thicker than the left. The length, breadth and thickness were positively correlated with age and body weight. Simple, branched, tubular and holocrine type of glands was covered by highly vascular connective tissue capsule composed of collagen and reticular fibres. Elastic and smooth muscle cells were absent. The secretory tubules showed two zones, an outer zone or zone I, near the capsule and an inner zone or zone II, towards the primary cavity. The epithelium of the tubules consisted of basal, intermediate and transitional cell layers. The papilla had two ducts, which were lined by glandular epithelium initially and keratinized type of stratified stratified squamous epithelium at the tip. The glandular epithelium was surrounded by longitudinally arranged smooth muscle fibres and skin. Lamellar corpuscles and circlet feather follicles were noticed in the papilla. Capsule, trabeculae and the parenchyma were PAS positive. Acid mucopolysaccharides and glycogen were not detected in the gland. Lipids were evident uniformly in all the cell layers. The acid phosphatase activity was moderate in the basal and intermediate layers and strong in the transitional layer. The alkaline phosphatase activity was moderate in the basal and intermediate layers and weak in transitional layer of outer zone. It was moderate in the basal and intermediate layers and intense in the transitional layer of inner zone. Micrometrical findings on the capsule thickness, width of outer and inner zones and the primary cavity increased with the advancement of age.
  • Thumbnail Image
    ThesisItemOpen Access
    Prenatal development of major lymphocenters and lymphatics in goats (Capra hircus)
    (College of Veterinary and Animal Sciences, Mannuthy, 2009) Asha, Antony; KAU; Maya, S
    Prenatal development of the major lymphocenters and lymphatics in goat was studied using 41 foetuses of various ages from 22 to 147 days of gestation. Morphogenesis and histogenesis of lymph nodes from five major lymphocenters, viz. parotid and mandibular from head, prescapular from neck, caudal mediastinal from thoracic cavity, jejunal mesenteric from abdominal viscera and prefemoral from abdominal wall and lymphatics, viz. tracheal and thoracic ducts and cisterna chyli were studied. During the first month, the lymphatic system presented six lymph sacs. By 22 days, paired jugular sacs and unpaired retroperitoneal sac appeared whereas, the cisterna chyli and paired iliac sacs appeared only by 24 days. Jugular sacs started to split into lymphatic spaces adjacent to the internal jugular vein and vagosympathetic trunk by 40 days. Retroperitoneal sac lay ventral to aorta, close to the root of the mesentery, near the kidney anlage and underwent regression by 53 days. Iliac sacs appeared near aorta, dorsolateral to Wolffian bodies and dorsomedial to metanephric kidneys and its onset of regression was by 50 days. Cisterna chyli appeared as a lymphatic space lateral to aorta and became a spindle-shaped dilatation at the level of last thoracic to first lumbar vertebra. By 48 days, thoracic duct formed the cranial continuation of cisterna chyli, near aorta. By 50 days, the tracheal lymph duct was seen in the developing carotid sheath. Valves appeared by fourth month in these ducts. Lymph sacs showed infiltration by lymphocytes and red blood cells by 48 days. The developing lymph nodes exhibited haemopoietic areas between 53 and 60 days. There was a progressive increase in the size of lymph nodes with age. The weight of the lymph nodes exhibited positive correlation with body weight, CRL and age. The superficial lymph nodes occurred as single ones and deep lymph nodes occurred in groups, with slight variation in position in some animals and slightly higher gross values for male animals and for the lymph nodes of right side. Capsule was undifferentiated up to 53 days and presented trabeculae by 75 days in parotid lymph node. The differentiated capsule presented dense fibrous connective tissue with collagen, elastic and smooth muscle fibers and was thicker where the cortex was more developed. Earliest aggregation of lymphocytes occurred in cortex by 60 days, in the parotid and mediastinal nodes. The nodular aggregations occurred by 75 days in the parotid lymph node, but by fifth month in all other nodes. Cortex was denser and thinner than the medulla. Medulla started differentiation by 75 days but macrophages and germinal centers were not detected till the end of gestation. Parotid and mandibular lymph nodes showed a similar pattern of development, but with a denser cortex for the latter. Prescapular lymph node presented lesser cortico-medullary differentiation than the corresponding stages in the lymph nodes of head. Even though the differentiation was slower during the initial stages, during the last month it became similar to that in the lymph nodes of head. Prefemoral lymph node followed a slower pattern of development with lesser number of trabeculae than parotid and prescapular lymph nodes. All lymph nodes presented nodular aggregation of lymphocytes in the cortex by fifth month, thereby attaining a structure similar to that in adults towards the end of gestation except for the absence of macrophages and reactive centers. Lymphocytic proliferation in the thymus preceded the appearance of lymphocytes in lymph nodes indicating these cells got differentiated first in the thymus. Contribution to the body weight of spleen and lymph nodes decreased towards the end of gestation indicating a similar development pattern. Only weak reactions were exhibited by the lymph nodes towards glycogen, acid and alkaline phosphatases and lipids. The superficial lymph nodes were encapsulated by deposition of fat from fourth month onwards.
  • Thumbnail Image
    ThesisItemOpen Access
    Postnatal development of the oviduct in the Kuttanad duck(Anas platyrhynchos domesticus)
    (College of Veterinary and Animal Sciences, Mannuthy, 2010) Patki Harshad, Sudhir; KAU; Lucy, K M
    The structure and postnatal development of the oviduct in the Kuttanad duck was studied using 78 ducklings from day-old to 24 weeks of age. The material was collected from six birds in each group at fortnightly intervals. In the day-old duckling, the left oviduct could be seen as a thin, thread-like, translucent, straight tube towards the left side of the coelomic cavity supported by the dorsal and ventral ligaments. Uterus and vagina were recognizable even at this age. Among the 78 birds, persistent right oviduct could be detected in 20 birds. Signs of coiling of the oviduct were evident from 10th week onwards. All the five segments of the oviduct namely, infundibulum, magnum, isthmus, uterus and vagina could be clearly distinguished from 12th week onwards. Rapid development of the organ occurred between 16 and 18 weeks at which stage a few birds started laying. A spurt in growth of the oviduct was noticed between 18 and 20 weeks when all the birds started laying. The contribution of oviduct to the body weight was 3.47% at 24th week of age. During postnatal period, correlation between age and the length of the oviduct was more significant than with the oviduct weight. Magnum was the longest and most coiled component. Isthmus, uterus and vagina were relatively longer.In the day-old duckling, the oviduct wall was not differentiated into different tunics and showed innermost simple columnar epithelium and subepithelial tissue. The lumen was flanked by characteristic low mucosal folds. At two weeks of age, the secondary mucosal folds started appearing. By 6th week, a very thin single layer of tunica muscularis appeared. The most dramatic growth and differentiation began at the age of 12 weeks when all the segments of the oviduct were differentiated morphologically and histologically. The tubular glands appeared as invaginations of surface epithelium and the mucosal folds became comparatively higher and broader at this age. Glands were absent in the funnel portion of infundibulum, magnum isthmus junction and vagina. The core of the mucosal fold showed numerous blood vessels. The lamina propria blended with the submucosa and muscularis mucosa was absent. Tunica muscularis was made up of inner circular and outer longitudinal smooth muscle layers and the thickness gradually increased from the cranial to the caudal direction. Distinct serosal tunic was visible in adult birds. The funnel region of the infundibulum showed mainly low primary mucosal folds with a few secondary folds whereas in the neck region, numerous tertiary folds were also present. In the adult birds, there were four types of epithelial cells in the mucosa of neck namely non-secretory ciliated cells; non-ciliated mucous-secreting goblet cells; secretory cells other than goblet cells and lining cells of the tubular glands. Goblet cells increased in number caudally. At the infundibulum-magnum junction, groups of infundibular glands intermingled with tubular glands of the magnum.In the magnum, mucosal folds were wider and higher and were lined by monolayered simple columnar ciliated epithelium with a few goblet cells. The glands of lamina propria were arranged in a radiating manner from the core to the periphery. Magnum-isthmus junction was characterized by complete absence of tubular glands. In the isthmus, by four weeks, the primary folds attained characteristic angular shape. In the adult birds, compared to all other segments of the oviduct, the glands in the isthmus were more loosely arranged. Regular alteration of both ciliated and secretory non-ciliated columnar cells was noticed in the lining epithelium. Isthmus - uterine junction showed an intermingling of glands within the lamina propria. The mucosal folds of uterus were higher, leaf-shaped and were separated by deep furrows. Light cells and dark cells were visible in the lamina epithelialis. At 16th week, glandular development continued and the closely packed tubular glands in the mucosal folds were empty during non laying phase. But, prior to and during secretory phase, cells contained pale staining granules and after the shell formation, the cytoplasm was markedly vacuolated, with relatively large basal nucleus. Tunica muscularis was very thick with an inner circular and thicker outer longitudinal layers separated by loose connective tissue showing numerous vessels and nerves. At this age, smooth muscle fibres were observed to be extending to the core of the mucosal fold along with numerous collagen fibres. At utero-vaginal junction the sperm storage tubules appeared at 12 weeks of age and were located in a thick ring of pushed-in mucosal folds found in the lumen with the vaginal folds on one side and uterine folds on the other. Mucosal folds towards the uterine side of the cranial utero-vaginal ridge contained transitional glands, which intermediate in appearance between sperm storage tubules and uterine glands. The sperm storage tubules were more sparsely distributed but had larger diameter than the transitional and uterine glands.At two weeks of age, the vagina showed roughly triangular seven to eight primary folds lined by tall columnar cells interspersed with numerous goblet cells. Even at this age, tunica muscularis was well developed and differentiated into inner circular and outer longitudinal layers. By 12 weeks, the folds were characteristically filiform in appearance with secondary folds. The lamina propria was devoid of glands. Vagina showed the thickest tunica muscularis among different segments of the oviduct. Lamina propria of mucosal folds of the vagina showed large number of lymphocytes along with diffused blood cells from four weeks-old birds. As age advanced, all regions of the oviduct showed lymphocytes in diffuse as well as aggregated form which was maximum in the vaginal region. The goblet cells found throughout the oviduct showed intense P.A.S. positive reaction. The presence of neutral and acid mucopolysaccharides was identified using P.A.S. and Alcian blue (pH 2.5) method in the epithelium of isthmus region; while in magnum, only the acid mucopolysaccharides were seen. The sperm storage tubules and transitional glands showed presence of lipid. The presence of glycogen was observed only in the epithelial lining and tubular glands of isthmus region and was more pronounced in adult egg laying ducks with actively secreting glands. Marked alkaline phosphatase activity was seen in the uterus, isthmus and magnum. The activity of Acid phosphatase was observed in the epithelium and tubular glands of isthmus, shell gland and vagina.