عنوان مقاله [English]
Anatomical and histomorphometrical study of sheep’s thymus was conducted by 75 apparently healthy fetuses that collected from Urmia’s industrial slaughterhouse. After anatomical study, the samples were fixed in 10% formal saline, passaged and histological paraffin sections prepared in 5-7 μm in thickness, and by H&E method stained. Histomorphometrical study performed by graded and latticed lens devises. Results of anatomical study showed that thymus begin to develop from cranial part of pericardium in the left side of cranial mediastinum and the ventral surface of neck, and it extend to ⅓ caudal part of neck, then it bifurcate to right and left sides and gain to the pharynx. Histomrphometrical study showed that, mean thickness of thymic lobules in thoracic part at 2nd month of fetal period, significantly was greater than the neck part, whereas, in 2nd half of 4th month in neck part it showed significantly increase(P<0.05). Mean thickness of cortex and medullae of lobules, from 2nd month until 2nd half of 3rd month in thoracic part was greater, but after that time, until 5th month it was significantly greater in neck part(P<0.05). Mean thickness of trabeculae decrease as fetus developing. Mean distribution of Hasal’s corpuscles from 3rd month until 5th month were increased, but, mean thickness of these corpuscles were increased until 4th month. This study showed that mean thickness of cortex and medullae of lobules were not significantly different in all fetal periods.
1- Arthur, GH.; Noakes, DE and Pearson, H. (1996) Veterinary reproduction and obstetrics. 6th Edn., Bailier Tindall, London, p: 62.
2- Banks, W. J. (1992) Applied Veterinary Histology, 3rd edn., (Mosby Year Book, St. Louis). pp. 289-292.
3- Dellmann, H. D. and Carithers, J. R. (1995) Cytology and microscopic anatomy., (Williams&Wlkins, Baltimore). pp.: 202.
4- Dyce, K. M.; Sack, W. O.; Wensing, C. J. G.(1996) Textbook of Veterinary Anatomy, 2nd Edn. (W. B. Saunders Company, Philadelphia). pp.: 612-613.
5- Eurell, J. A. and Frappier, B. L. (2006) Dellmann’s Text book of veterinary hististology, 5th Edn., (Blackwell, UK). pp.:134-152.
6- Getty, R.(1975) Sisson and Grossman’s The Anatomy of the Domestic Animals, 5th Edn. Vol. 1., (W. B. Saunders Company, Philadelphia). pp.: 181-, 1064.
7- Humson, G (1979) Animal tissue techniques. 4th Edn., W. H. Freeman and co., Sanfrancisco, pp: 137-138.
8- Latshaw, W. K.(1987) Veterinary Developmental Anatomy., (B.C. Decker Inc., Philadelphia). pp.: 106-107.
9- Liberti, E. A.; Villa, N.; Melhem, S. A.; Matson, E.; Konig, B., Jr.; Adamo, J. (1989) A morphometrical study of human fetal thymus. Z Mikrosk Anat Forsch 103(2): 309-15.
10- Moura-Campos, L. C. and W. Savino (1988) Morphometrical analysis of the thymus from mice submitted to low temperature. Acta Anat (Basel) 132(1): 9-11.
11- Mukamoto, M. and Kodama, H. (2000) Regulation of early chicken thymocyte proliferation by transforming growth factor-β from thymic stromal cells and thymocytes. Veterinary Immunology and Immunopathology., 77(1/2): 121-132.(Veterinary Bulletin., 71(5): 596. Abs No.3672).
12- Nickel, R.; Schummer, A.; Seiferle, E. (1981) The anatomy of the domestic animals. Vol. 3., (Verag Paul PAREY, Berlin). pp.: 283-292.
13- Ober, M. N. and K. V. Prahlad (1987) Ultrastructure of thymus and liver following adrenalectomy and replacement adrenal hormone therapy in rats. Cytobios 52(209): 71-82.
14- Oner, H. and E. Ozan (2002) Effects of gonadal hormones on thymus gland after bilateral ovariectomy and orchidectomy in rats. Arch Androl 48(2): 115-26.
15- Prakash, A. and Chandra, G. (1999) Histomrphometrical observations on the medulla of prenatal thymus of buffalo (Bubalus bubalis). Indian Journal of Veterinary Anatomy., 11(1): 19-23. (Veterinary Bulletin., 70(3): 377. Abs No. 2193).
16- Ravinder K. Suniara, Eric J. Jenkinson, and John J.T. Owen.(2000) An Essential Role for Thymic Mesenchyme in Early T Cell Development. The Journal of Experimental Medicine, Volume 191, 1051-1056
17- Sadler, T. W. (1993) Longman’s Medical Embryology. 6th Edn., (Williams&Wilkins), pp: 306-307.
18- Sakabe, K., Okuma, M., Karaki, S., Matsuura, S., Yoshida, T., Aikawa, H., Izumi, S., Kayama, F. (1999) Inhibitory effect of natural and environmental estrogens on thymic hormone production in thymus epithelial cell culture. Int J Immunopharmacol 21(12): 861-8.