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

Studies on the Food and Feeding Habits and Electivity Indices of Young Freshwater Cyprinid Mola Amblypharyngodon Mola

S.M. Rahmatullah
Department of Aquaculture and Management, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh

S.M. Nurrunnabi
Department of Aquaculture and Management, Bangladesh Agriculturail University, Mymensingh-2202, Bangladesh

M.A. Salam
Department of Aquaculture and Management, Bangladesh Agriculturail University, Mymensingh-2202, Bangladesh

Abstract/ Executive Summary:

A food selection and electivity study was carried out of pond-reared young mola Amblypharyngodon mola (15 to 25 mm SL). Fish was fed on a wide variety of food items. Food analysis by points method indicated that fish was fed mainly on phytoplankton and detritus. Electivity analyses showed that fish strongly selected phytoplankton species (Chrococcus and Tetraedron) and also selected some zooplankton (Diaphanosoma, Diaptomus , Cyclops) species at early life stage. Two active feeding peaks were observed during the dial pattern of study ( 14. 00 and 18.00 h). Gill- raker length and inter gill-raker space increase with the increase of body length. The fish changes its food habit as it grows.

Keywords: Food, Feeding, Electivity, Young, Freshwater , Mola

Location: BAU, Mymensingh

Start Date: 00-06-1994

End Date: 00-07-1994

Program Area: Animal Health and Management

Commodity: Fish

Objectives:

To investigate the feeding habits and electivity indices of young freshwater mola and the morphometries of the feeding apparatus.

Methodology:

A non-drainable, rain-fed earthen pond measuring 800 m ² (40m x 20m) at the Bangladesh Agricultural University campus, Mymensingh, was selected and limed and fertilized at regular intervals so that a thriving plankton community was established. A breeding population of mola was established from fish taken from a nearby reservoir. Trials were conducted for a period of 45 days during June and July, 1994. Ten 1 litre samples of water were collected every weeks from different areas and depths of the pond in order that a representative sample of the community was taken. Samples were filtered through a fine-mesh plankton net, the collected material being carefully washed into plastic jars and made up to a standard volume with water and preserved in 5% buffered formalin. Ninety fishes, ranging from 15.0 to 25.0 mm standard length, were sacrificed for gut contents analysis over the course of the experiment. Samples of approximately 25 fishes were taken from the pond at two weeks interval using a seine net. Fishes were killed immediately by a blow to the head and measured. The body cavity was carefully opened and gut fullness assessed on a scale 1 for 1 / 4 full, 2 for 1 /2 full, 3 for 3/4 full and 4 for full. Gut contents from the anterior portion of the gut were carefully washed into a petridish and analyzed. The feeding apparatus {gill arches) were carefully excised from 50 fishes and preserved in 10% buffered formalin for morphometric analysis. The mid-section of the second gill arch from one side of each fish was used. The length of five gill rakers and the distance between five pairs of adjacent gill rakers were made from each gill arch sample. Examination was done by light microscope fitted with an eyepiece graticule.

Source of Information: Bangladesh J. Agril. Sci. 24(2): 81-86, July, 1997;ISSN 0379-4296

Article Link (Online Journal):

Funding Source:

Total Budget (Tk.) :

Achievement/Findings:

Average index of stomach fullness increased with the increase of body size. The result indicated that mola had two peak feeding activities, one is at 14.00 hour and other is at 18.00 hour. At dawn the stomach of the fish was found half fullness with an increasing feeding intensity and at around 14. 00 hour feeding activities reached at a peak level. Mola is a selective feeder in pond conditions. Among the phytoplankton, fishes were found to be positively selected Chrococcus, and Tetaedron. Although large numbers of other phytoplankton were found in the gut contents, all were negatively selected. Zooplankton was also found in the gut contents which was decreasing with the increase of body size. Gill raker length increased with the increase of fish body size. The highest and the lowest gill-raker length was 138 and 84 Jim, respectively a mean length of gill- raker was 112.15 µm. From the present experiment, comment may be made that mola is a school forming surface feeder

Knowledge Management: Journal