The Histological Effects of Salt Stress on the Digestive Tract of Pseudotropheus acei Fish

Yıl 2025, Cilt: 15 Sayı: 4, 1472 - 1489, 15.12.2025

Enes Yıldırım , Zehra Alkan , Ahmet Regaib Oğuz

https://doi.org/10.31466/kfbd.1600454

Öz

The digestive tract is responsible for food digestion in fish, as it is in all living organisms. Feeding habits, canal structure, and morphology of fish vary among species. The mucous cells in the mucosal layer of the digestive tract are influenced by factors such as salinity, ion regulation, pH, pollutants, parasites, and stress. Salinity is one of the most important factors affecting fish growth, nutrition, metabolism, and other physiological activities. In our experimental study, different concentrations of salt were applied to Pseudotropheus acei fish. It was observed that the fish adapted to a maximum salinity of 27 ppt and died at higher salinities. The digestive tract tissues of both control and salinity-adapted fish were examined histologically. The histological studies revealed that the digestive tract of Pseudotropheus acei consisted of four layers: serous, muscularis, submucosa, and mucosa. Mucus cells in the digestive tract of fish exposed to salt stress were counted from 15 different regions and statistically analyzed. Statistical analysis revealed that the number of mucus cells containing neutral glycoconjugates was 267.4 in the control group, 328.66 in the 20 ppt group, and 360 in the 27 ppt group. The densities of neutral, carboxylated, O-sulfate ester, strongly sulfated, and sulfated glycoconjugates in the mucus cells, important cells within the digestive tract, were determined histochemically using Periodic Acid/Schiff (PAS), Alcian Blue at pH 2.5, Alcian Blue at pH 1.0, Alcian Blue at pH 0.5, and Aldehyde Fuchsin stains. It was concluded that salinity stress had a significant effect on the mucus cell densities and content in fish living in aquatic environments.

Anahtar Kelimeler

Histology , Mucus Cell , Digestive tract , Salinity

Proje Numarası

1919B012213680

Tuz Stresinin Pseudotropheus acei Balığının Sindirim Kanalı Üzerindeki Histolojik Etkileri

Öz

Sindirim kanalı tüm canlılarda olduğu gibi balıklarda da besinlerin sindiriminden sorumlu organdır. Balıkların beslenme şekli, kanal yapısı ve morfolojisi türden türe farklılık göstermektedir. Balıklarda sindirim kanalı mukoza tabakasında bulunan mukus hücreleri tuzluluk, iyon regülasyonu, pH, kirletici, parazit ve stres gibi faktörlerden etkilenmektedir. Tuzluluk balık büyümesi, beslenmesi, metabolizması ve diğer fizyolojik aktiviteleri etkileyen en önemli parametrelerden biridir. Bu çalışmada Pseudotropheus acei balıklarına farklı tuz konsantrasyonları uygulandı. Uygulama sonucunda balıkların en fazla 27 ppt tuzluluğa adapte olduğu daha yüksek tuzluluklarda ise öldüğü gözlendi. Kontrol ve tuzluluğa adapte olan gruplardaki balıkların sindirim kanalları histolojik olarak incelendi. Yapılan çalışmalar sonucunda Pseudotropheus acei balığı sindirim kanalının seröz, muskularis, submukoza ve mukoza tabakalarından oluştuğu görüldü. Tuz stresine maruz kalan balıkların sindirim kanalı mukus hücreleri 15 farklı bölgeden sayılarak istatistiksel olarak analiz edilmiştir. İstatiksel analiz sonucu, nötral glikokonjugat içeren mukus hücre sayısının kontrol grubunda 267.4, 20 ppt grubunda 328.66 ve 27 ppt grubunda 360 olduğu görüldü. Sindirim kanalında bulunan önemli hücrelerden biri olan mukus hücrelerinin nötral, karboksilatlı, O-sülfat esterli, güçlü sülfatlı ve sülfatlanmış glikokonjugat yoğunlukları Periyodik Asit/Schiff (PAS), Alcian Blue pH 2.5, Alcian Blue pH 1.0, Alcian Blue pH 0.5 ve Aldehit fuksin&Alcian Blue pH 2.5 boyaları ile histokimyasal olarak belirlendi. Tuzluluk stresinin balıklarda sindirim kanalında bulunan mukus hücre yoğunlukları ve içeriği üzerine etkili olduğu görüldü.

Anahtar Kelimeler

Histoloji , Mukus Hücresi , Sindirim Kanalı , Tuzluluk

Etik Beyan

Van Yüzüncü Yıl Üniversitesi Hayvan Araştırmacıları Yerel Etik Kurulu (YUHADYEK 2023/05-36)

Destekleyen Kurum

TÜBİTAK 2209-A üniversite öğrencileri araştırma destek programı

Proje Numarası

1919B012213680

Kaynakça

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