Agricultural Research Management Information System

Home
Research Summary
Search
About Us
- ARMIS
- Brochure
Contact Us
Report
User Request
Data Input
Help
- Operation Manual
  - PDF
  - Video
- Program Area & Commodity
We have reached 37600 number of research entries at this moment.

- Logout

Research Detail

Home
Research
Detail

Histopathology of the Intestine of Clarias Batrachus L. Under Heavy Metal Stress

SHAWKAT ARA BEGUM
Department of Zoology, University of Chittagong, Chittagong-4331, Bangladesh

BAHARUL HOQUE
Department of Zoology, University of Chittagong, Chittagong-4331, Bangladesh

QAMAR BANU
Department of Zoology, University of Chittagong, Chittagong-4331, Bangladesh

Abstract/ Executive Summary:

Histopathological effect of three heavy metals- cadmium, chromium and mercury on intestine of Clarias batrachus L. was studied under laboratory condition. The common histopathological changes that took place under heavy metal exposure were disintegration of mucosal epithelium, hypertrophied epithelial cells, increased number of goblet cells, sloughed off epithelial cells and mucous in the lumen, degeneration of the connective tissue of sub-mucosa and hyperemic blood vessels. .Separation of mucosal epithelium, especially in the villi and increased goblet cells were prominent in Cd-exposed fish. Clumping of the epithelial cells at the base near the basement membrane was prominent in the case of the Cr- and Hg-exposure. Connective tissue degeneration in the lamina propria and submucosa of the intestine and dilated blood vessels with congestion of blood were prominent in the Cr and Hg exposed fish.

Keywords: Histopathology, Mucosal epithelium, Hypertrophy, Goblet cell

Location: Department of Zoology, University of Chittagong, Chittagong

Start Date:

End Date:

Program Area: Animal Health and Management

Commodity: Heavy metal

Objectives:

1. The present work is an attempt to investigate the toxic effect of three heavy metals- cadmium (Cd), chromium (Cr) and mercury (Hg) on the intestine of Clarias batrachus L.

Methodology:

Fresh and live specimens of Clarias batrachus L. (average length 16 ± 3 cm and weight 70 ± 5 g) was bought from Chittagong city market and acclimatized for 7 days in 25 L aquarium in nonchlorinated tap water. Fish species were given oligochaetes, prawn and small pieces of Harpodon nehereus as food once a day, and water was changed at 24h interval. Following it, 15 fish specimens in each 25L aquarium were exposed to each sub lethal conc. of heavy metals (Cd– 9 ppm, Cr– 12 ppm and Hg – 0.3 ppm) for 28 days along with a control without heavy metal. Test fishes in the aquarium were fed once a day with a change of solution after each feeding. Standard method was followed for histopathological study. At the end of the exposure period intestine from the metal exposed as well as control fishes were isolated, cleaned with physiological saline solution, cut into pieces and fixed in freshly prepared Bouin’s fixative. After 24 hours tissues were transferred to 70% alcohol for preservation. For histological slide preparation tissues were dehydrated in graded alcohol, cleared in benzene and embedded in paraffin. Thin sections (3-5µ) were cut by a rotary microtome, double stained by eosin-haematoxylin, mounted with DPX for examination under microscope. Photomicrographs were taken by Ricoh 35 mm SLR camera.

Source of Information: The Chittagong Univ. J. B. Sci.,Vol. 5(1 &2):45-53, 2010

Article Link (Online Journal):

Funding Source:

Total Budget (Tk.) :

Achievement/Findings:

In the present study, connective tissue degenerations were noticed in the lamina propria and submucosa of the intestine. Such degenerative changes were prominent particularly in the Cr and Hg exposed fish. Besides, dilated blood vessels with congestion of blood were also noticed in those fishes.

Knowledge Management: Journal