Abstract
Columnaris disease is a serious disease in warm water fish. It is caused by Flavobacterium columnare, a Gram-negative bacterium. In this work, fucoidan was tested for its efficacy in decreasing the mortalities caused by Columnaris disease in Nile tilapia. Consequently, naturally-infected Nile tilapia with Flavobacterium columnare, showing eroded fins, rigid body figure, and ulcerated body surface, was treated with fucoidan (8 gm/kg ration) for 17 days. Flavobacterium columnare infection was confirmed by isolation on selective medium (cytophaga agar), from the skeletal muscle, tails fins, and gills, giving the typical rhizoid shape. It was also confirmed by Flavobacterium columnare specific PCR using selective primers for Flavobacterium columnare 16S ribosomal DNA. Fucoidan caused decreased the mortalities to nil and cured the eroded fins, the ulcerated body surface, and the rigid body figure. Fucoidan also decreased the tissue damage score to reach the normal histological score.
Highlights
Fucoidan, is a branched sulphated fucan extracted from brown seaweeds and marine plants, e.g. tangleweed (Lami-naria japonica), wakame (Undaria pinnati da Sporophyll) and limu moui (Cladosiphon okamuranus) [1]
Flavobacterium columnare infected Nile tilapia was treated with fucoidan to test its efficacy on decreasing the escalating mortalities and the evolved cutaneous lesions caused by infection
Following 24h of incubation on the selective medium, isolation of Flavobacterium columnare was confirmed by its microbial growth on the selective medium, where colonies on were flat, rhizoid, strongly adherent, and spread across solid media surfaces forming irregular margins Figure 1
Summary
Fucoidan, is a branched sulphated fucan extracted from brown seaweeds and marine plants, e.g. tangleweed (Lami-naria japonica), wakame (Undaria pinnati da Sporophyll) and limu moui (Cladosiphon okamuranus) [1]. Fucoidan is known for its anti-bacterial, anti-viral, immunostimulatory, and healing stimulating effects [2,3,4,5,6,7,8,9,10,11]. Columnaris disease is caused by Flavobacterium columnare, a Gram-negative bacterium. It was first reported in 1922 and is one of the most frequently occurring diseases in freshwater fish [12]. The disease commonly causes serious cutaneous and gill lestions [12,13,14]. Flavobacterium columnare infected Nile tilapia was treated with fucoidan to test its efficacy on decreasing the escalating mortalities and the evolved cutaneous lesions caused by infection. The experiment was conducted under ‘Guide for the Care and Use of Laboratory Animals’ approved by the Ethics Committee of the Faculty of Veterinary Medicine, Mansoura University
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
