structure and arrangement of photoreceptors in the retina of big eye kilka, clupeonella grimmi (kessler 1877)
نویسندگان
چکیده
the big eye kilka, clupeonella grimmi, is a marine fish living in depth of 20 to 200 meter of the caspian sea. its eye and retina were processed for histological and sem studies. paraffin embedded retina was cut radially and tangentially in 5 ?m thickness and stained with hematoxylin and eosin method. the unstained sections were manipulated for sem image observations. tangential retinal sections showed irregular arrangement of cones. five morphologically different types of photoreceptors were distinguished as rods, short single cones, long single cones, twin cones and double cones. the cones were counted in each quadrant of the retina and cone density was determined. the cones showed increment in diameter but reduction in number at anti-clockwise direction without any specific arrangement. presence of four types of cone cells and their pattern of distribution revealed assistance in near surface color vision and more light capture in dim light of deeper waters as an adaptation to planktivorous feeding habit and deep water living habitat.
منابع مشابه
Structure and arrangement of photoreceptors in the retina of big eye kilka, Clupeonella grimmi (Kessler 1877)
The big eye kilka, Clupeonella grimmi, is a marine fish living in depth of 20 to 200 meter of the Caspian Sea. Its eye and retina were processed for histological and SEM studies. Paraffin embedded retina was cut radially and tangentially in 5 ?m thickness and stained with hematoxylin and eosin method. The unstained sections were manipulated for SEM image observations. Tangential retinal sect...
متن کاملAge and growth of bigeye kilka (Clupeonella grimmi Kessler, 1877) in Iranian waters of the Caspian Sea
Age and growth of Bigeye Kilka, Clupeonella grimmi, were studied in Iranian waters of the Caspian Sea from early May 2006 to April 2007. The sagitta otoliths were removed for each 5 mm length interval up to a total number of 262 fish. Fork length and weight ranged from 92.5 to 142.5 mm and 4.2 g to 23.4 g, respectively. The largest length-groups was observed from December to February and the lo...
متن کاملAge and growth of bigeye kilka (Clupeonella grimmi Kessler, 1877) in Iranian waters of the Caspian Sea
Age and growth of Bigeye Kilka, Clupeonella grimmi, were studied in Iranian waters of the Caspian Sea from early May 2006 to April 2007. The sagitta otoliths were removed for each 5 mm length interval up to a total number of 262 fish. Fork length and weight ranged from 92.5 to 142.5 mm and 4.2 g to 23.4 g, respectively. The largest length-groups was observed from December to February and the lo...
متن کاملEffect of Clupeonella grimmi (anchovy/kilka) fish oil on dysmenorrhoea.
To examine whether dietary supplementation with omega-3 fatty acids from Clupeonella grimmi can relieve symptoms of dysmenorrhoea, we carried out a cross-over clinical trial on 36 girls aged 18-22 years. They were randomly allocated into 2 groups of 18. Group A received 15 mL fish oil daily (550 mg eicosapentaenoic acid; 205 mg decosahexaenoic acid) while Group B received placebo. After 3 month...
متن کاملبررسی ساختار جمعیت کیلکای چشم درشت Clupeonella grimmi Kessler, 1877 در سواحل استان مازندران
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عنوان ژورنال:
caspian journal of environmental sciencesناشر: university of guilan
ISSN
دوره 12
شماره 1 2014
کلمات کلیدی
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