Thumbnail Image

Kerala Veterinary and Animal Sciences University, Wayanad

Browse

20221
Reset filters
Subject: Veterinary Anatomy and Histology × Author: SIMANTA PATGIRI × End date: 2023 × Start date: 2020 × Thesis Type: M.V.Sc. ×
Reset filters

Search Results

Now showing 1 - 1 of 1
  • Thumbnail Image
    ThesisItemOpen Access
    HISTOMORPHOLOGY AND ULTRASTRUCTURE OF THYROID AND ADRENAL GLANDS IN LARGE WHITE YORKSHIRE PIGS REARED AT HIGH AND LOW ALTITUDES
    (COLLEGE OF VETERINARY AND ANIMAL SCIENCES POOKODE, 2022-04-04) SIMANTA PATGIRI; Rajani C.V.
    Thyroid and adrenal glands of the Large White Yorkshire pigs reared at high and low altitude was studied to investigate the comparative morphology, micrometry and ultrastructure and serum hormone level in animals reared at low and high altitude. Materials for the study were collected from 24 Large White Yorkshire pigs of one year old categorized into four groups with respect to sex and altitude. Each group consisted of 6 animals. The thyroid and adrenal glands were collected from each animal. Observations on morphology, histology, histochemistry, electron microscopy, morphometry and micrometry were carried out and data were analyzed statistically to find out any significant difference. The thyroid gland in Large White Yorkshire pig was laterally covered by the cranial thymus. The position of the gland varied from the caudal border of the larynx to a position dorsal to the manubrium sterni. Thyroid resembled a single centrally-placed gland but after dissection, it revealed two lobes connected by an indistinct isthmus. The average weight of the thyroid gland of both male and female animals in low altitude was more than high altitude. The average length of intact thyroid gland in male and female was more in high altitude compared to low altitude. The average width and thickness of the intact thyroid gland in both male and female groups were more in low altitude than the corresponding high altitude group. The capsule of thyroid gland extended as fine trabeculae of interlobular connective tissue into the parenchyma of the gland and separated it into numerous lobules. The thyroid follicle had a maximum diameter of 301.35 μm. The diameter of thyroid follicles was more in the central area and it reduced towards the peripheral area. Parafollicular or C-cells were present in 3 locations viz. interfollicular, intrafollicular and parafollicular position. The diameter of the thyroid follicle in the high altitude male group was significantly higher than that of the low altitude male group but it was reverse in case of female animal. The thyroid follicle diameter was higher in female compared to male animals irrespective of altitude. The adrenal glands were detected either cranio-medial or entirely on the medial surface of the kidney and embedded entirely within the perirenal fat of the kidney. In low altitude male group, the average weight of right and left adrenal was higher than the corresponding high altitude group but it was reverse in case of low altitude female animals. In the low altitude, the average thickness of right and left adrenal was higher than that of high altitude for both male and female groups. In low altitude female group, the average length of right and left adrenal was lower than that of high altitude female group. In low altitude female group, the average thickness of right and left adrenal was more than that of high altitude group. Histologically, the adrenal gland presented outer cortex and inner medulla. The gland was entirely surrounded by a dense and distinct fibrous connective tissue capsule. The inner zone of the capsule extended very thick trabeculae enclosing blood vessels at right angles from the capsule, at regular intervals into the cortex towards the medulla. However, trabeculae were indistinct from zona fasciculata inwards. A few trabeculae enclosing blood vessel extended even upto the medulla. The boundary between the deeper part of the capsule and zona glomerulosa layer revealed a group of relatively undifferentiated 'capsular' cells. The junction of zona glomerulosa and zona fasciculata presented lightly stained undifferentiated cells were observed. For both male and female animals, the average thickness of zona glomerulosa of right and left adrenal gland were significantly higher in high altitude group than the respective low altitude group. The zona reticularis in the sow was usually wider than that in the boar in all the groups studied. In male pigs, the average serum T3, T4 and cortisol level were significantly higher in low altitude group compared to that of high altitude group. In female pigs, the average serum T4 and cortisol level were significantly higher in low altitude group compared to the high altitude group. The average serum cortisol level in males were significantly higher than that of female animals in both low and high altitude. Irrespective of sex, the average serum T3, T4 and cortisol level were significantly higher in low altitude group than that of high altitude group.