نوع مقاله : مقاله پژوهشی
نویسندگان
1 گروه تولید و بهره برداری آبزیان، دانشکده شیلات و محیط زیست، دانشگاه علوم کشاورزی و منابع طبیعی گرگان، گرگان، ایران.
2 مرکز تحقیقات شیلاتی آبهای دور، موسسه تحقیقات شیلات ایران، سازمان تحقیقات، آموزش و ترویج کشاورزی، چابهار، ایران
چکیده
کلیدواژه‌ها
عنوان مقاله [English]
نویسندگان [English]
Introduction: It is clear that the correct knowledge of scales and the identification of fish without scales are specialized propositions that cannot be achieved without the necessary knowledge. The body of most fish is covered with scales. The scales are made of horny or bony material.
Methods: Scales from the dorsal fin are slowly separated from the body of the fish. Place in sodium hypochlorite solution to remove mucus or other undissolved material. The scales are then washed and dehydrated in ethanol series. Finally, it is covered with a thin layer of gold and examined by electron microscopy.
Results: All cartilaginous fish have placoid or plate scales or serrated teeth on the outer surface of their body. Many eels, such as freshwater eels, have small, elliptical cycloid scales that attach to the skin. Catfish generally do not have clear and uniform scales and their bodies are often naked. Catfish do not have distinct scales and instead have leathery skin. Catfish evolved differently and have no scales.
Conclusion: The presence of scales in all cartilaginous fish (shark, shield and table fish) and some snake fish is clearly confirmed and proven, but in catfish the usual structure of scales is not confirmed and instead skate structures that have the same function as scales. And plays the role of scales or sequins is approved.
کلیدواژه‌ها [English]
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