Histological Insights into the Gastrointestinal Tract of Pelophylax bedriagae (Anura: Ranidae)

Abstract

In the present study, we carried out a comprehensive histological examination on the gastrointestinal system of a widely distributed frog Pelophylax bedriagae (Anura: Ranidae). The aim was to reveal the structural adaptations and functional properties of the digestive system of this amphibian species. The gastrointestinal tract consists of four main layers from inside to outside: mucosa, submucosa, muscularis externa, and serosa. The stomach structure of P. bedriagae's innermost mucosa layer consists of columnar cells that secrete mucus. The small intestinal features have deep folds and are lined with columnar and goblet cells. The large intestinal mucosa layer has smaller folds and is lined with columnar epithelial cells, with an increasing abundance of goblet cells noted from the small to large intestinal system. Notably, P. bedriagae's small intestine lamina propria also included abundant dense lymphoid aggregates, which may have a role in the immune defense of the frog. Overall, through a histological analysis of the digestive tract on P. bedriagae we have provided valuable information on the structural adaptations for digestion and uptake of nutrients for this amphibian species. These results contribute fundamental reference data to perform more effective research in amphibian anatomy and ecology.

Keywords

• Histology
• Amphibian
• Digestion
• Goblet cell
• Oxynticopeptic

Supporting Institution

This study was not supported by any project.

Ethical Statement

Ethics Committee Approval was obtained for the animal experiment in this article with the decision of “Ege University Animal Experiments Local Ethics Committee” dated: 25.07.2018, numbered 2018-077.

Pelophylax bedriagae (Anura: Ranidae)'nin Gastrointestinal Sistemine İlişkin Histolojik Bilgiler

Abstract

Bu çalışmada, yaygın olarak bulunan Pelophylax bedriagae (Anura: Ranidae) kurbağasının gastrointestinal sistemi üzerine kapsamlı bir histolojik analiz gerçekleştirilmiştir. Söz konusu amfibi türünün sindirim sistemine ait yapısal adaptasyonlar ile işlevsel özelliklerin ortaya konulması amaçlanmıştır. Gastrointestinal sistem, içten dışa doğru mukoza, submukoza, muskularis eksterna ve seroza olmak üzere dört ana katmandan oluşur. P. bedriagae (Levanten ova kurbağası) midesinin en içteki mukoza tabakası mukus salgılayan silindirik hücrelerden oluşur. İnce bağırsak yapısı derin kıvrımlar, silindirik ve goblet hücreleri içerir. Kalın bağırsak mukoza katmanları daha küçük kıvrımlara sahiptir ve silindirik epitel hücreleri kaplıdır. İnce bağırsaktan kalın bağırsak sistemine doğru giderek artan goblet hücreleri görülmektedir. P. bedriagae'nin ince bağırsak lamina propriasının, kurbağanın bağışıklık savunmasında rol oynayabilecek bol miktarda yoğun lenfoid yapılar içerdiği dikkat çekicidir. Genel olarak, P. bedriagae'nin sindirim sisteminin histolojik analiziyle, bu amfibi türünün sindirim ve besin alımına yönelik yapısal adaptasyonları hakkında değerli bilgiler sağlanmıştır. Bu sonuçlar, amfibi anatomisi ve ekolojisi alanında daha etkili araştırmalar yapmak için temel verileri sağlamaktadır.

Keywords

• Histoloji
• Amfibi
• Sindirim
• Goblet hücresi
• Oksintikopeptik

Supporting Institution

Bu çalışma herhangi bir proje tarafından desteklenmemiştir.

Ethical Statement

Bu makalede yer alan hayvan deneyi için “Ege Üniversitesi Hayvan Deneyleri Yerel Etik Kurulu” nun 25.07.2018 tarih ve 2018-077 sayılı kararı ile Etik Kurul Onayı alınmıştır.

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