1Division of Fish Nutrition, Biochemistry and Physiology, ICAR-Central Institute of Fisheries Education, Mumbai-400 061, Maharashtra, India
2College of Fisheries, (Bihar Animal Sciences University-Patna), Kishanganj-855 107, Bihar, India
3College of Fisheries, Dr. Rajendra Prasad Central Agricultural University, Muzaffarpur-843 121, Bihar, India
4ICAR-Central Institute of Fisheries Technology, Willingdon Island, Kochi-682 029, Kerala, India
*Corresponding Author: Susmita Rani, Division of Fish Nutrition, Biochemistry and Physiology, ICAR-Central Institute of Fisheries Education, Mumbai-400 061, Maharashtra, India, Email: susmitarani@basu.org.in
**Corresponding Author: Prem Prakash Srivastava, Division of Fish Nutrition, Biochemistry and Physiology, ICAR-Central Institute of Fisheries Education, Mumbai-400 061, Maharashtra, India, Email: dean.cof@rpcau.ac.in
The 60-day experimental study investigated the expression of iron regulatory genes, namely ferritin, transferrin and hepcidin, in Clarias magur fingerlings fed diets supplemented with two dietary iron sources. The experimental study comprised two groups in which C. magur fingerlings received diets supplemented with ferrous or ferric citrate at doses of 0, 15, 30, and 45 mg Fe/kg above the minimum dietary iron requirement of 30 mg Fe/kg diet, respectively.
Ferritin, transferrin, hepcidin expression levels in fish intestine, liver, muscle and gill tissues were determined using quantitative-real time PCR (qRT-PCR). Regardless of the dietary iron source, all tissues exhibited expression of the three genes under investigation, however, the degree of expression varied amongst tissues.
Liver showed highest ferritin mRNA expression among all tissues under both iron sources. Maximum expression (6.77-fold) was observed at 45 mg/kg ferrous citrate. Muscle showed modest changes while gill exhibited the lowest ferritin expression. In intestine, under ferrous citrate supplementation, transferrin expression increased with increasing iron level. Maximum expression (4.21±0.14) was recorded at 45 mg/kg iron supplementation. Liver transferrin expression increased with increasing ferrous citrate. Highest expression was observed at T3 (3.31±0.07). In intestine, the highest hepcidin expression occurred at T1 (5.62±0.01). Ferric citrate showed comparatively lower expression in all treatments. Liver showed the highest hepcidin expression among all tissues. Expression increased significantly with increasing iron supplementation. Maximum expression (7.99±0.06) was observed in fish fed 45 mg/kg ferrous citrate (T3).
Ferric citrate, Ferritin, Ferrous citrate, Gene expression, Hepcidin, Transferrin
