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

Effects of Dietary Polyunsaturated Fatty Acid on Reproduction and Developmental Biology of Gangetic Mystus (mystus Cavasius) (hamilton-buchanan, 1822)

Rafia Akter
Department of Fisheries Biology and Genetics, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh

Noore Safa Ema
Department of Fisheries Biology and Genetics, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh

Md Saddam Hossain
Department of Fisheries Biology and Genetics, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh

Zakir Hossain
Department of Fisheries Biology and Genetics, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh

Abstract/ Executive Summary:

The present study was undertaken to determine the effects of polyunsaturated fatty acids (PUFAs) on enhanced maturation, spawning, embryonic and larval development of endangered Gangetic Mystus (Mystus cavasius). Fishes were collected from the Brahmaputra River, Mymensingh, Bangladesh and stocked in the cisterns. The treated group was provided a supplemental diet enriched with 1% squid extracted lipids as a source of PUFAs four months whereas the controlled group fed the same diet except for PUFAs. In comparison with the control group, the treated group exhibited higher reproductive performances in the spawning trial. The fertilization rate (79.5±1.49), hatching rate (72.29±1.78) and survival rate (64.31±0.48) of offspring were significantly higher in the treated group compared to the control. Consequently, early embryonic and larval development was observed in the treated fishes. Therefore, the present study indicates the enhanced reproductive and developmental performances of (Mystus cavasius) owing to PUFAs supplementation in the diet.

Keywords: Mystus cavasius; PUFAs; Embryonic development; Larval development; Reproduction

Location: Fish Genetics and Biotechnology of the Faculty of Fisheries, Bangladesh Agricultural University, Mymensingh-2202.

Start Date:

End Date:

Program Area: Resource Development and Management

Commodity: Cat fish

Objectives:

The present study describes the effects of dietary PUFAs on reproductive biology and developmental process of M. cavasius.

Methodology:

The spawning conducted in the Mini Hatchery Cum Breeding Complex of the Department of Fisheries Biology and Genetics and observation of development was conducted in Laboratory of Fish Genetics and Biotechnology of the Faculty of Fisheries, Bangladesh Agricultural University, Mymensingh-2202. Prior to stocking the broodfish, two cisterns (1.22m×2.44m×0.46m) were washed, cleaned thoroughly and filled up with water. The water level was maintained at 30cm. The outlet of each cistern was equipped with the net with a metal structured small meshed net. The required number of M. cavasius was collected from local fisherman caught from the wild stock of the Brhamaputra river. Upon arrival at the faculty, fish were sexed and conditioned for about 15 days. Then healthy, strong and nearly equal-sized fish having an initial average length (15.23 ± 1.72) cm, the weight of the individual fish (41.75 ± 2.56) g, and gonad (2.34 ± 0.25) g were stocked for the experiment. Temperature, dissolved oxygen (DO) and P^H of the water in each cistern were recorded daily. Temperature, DO and pH were recorded by using a Celsius thermometer, a digital DO meter (multi 340 sets, DO-5509; China) and a portable digital pH meter (MICRO-TEMP, pH 500, Romania), respectively. The whole squid was collected from fishery ghat, Cox’s Bazar, Bangladesh. The whole squid was first allowed to thaw and washed with clean tap water. The squid was chopped after removing the cuttlebone and ink gland. Total lipids enriched with PUFAs from squid were extracted following the method of Bligh and Dyer (1959) with slight modification. The feed containing PUFAs was prepared including the fish meal (40%), rice bran (20%), wheat bran (15%), maize meal (13.5%), Vit-B complex (0.5%), total lipids (1%) and wheat flour (10%). While in control, 1% soybean oil was used instead of extracted squid oil. Ingredients were ground finely by a grinding machine and sieved with a fine mesh net. After sieving, the required amount of each ingredient was weighed as per formulae with a sensitive electric balance (ANDGULF, Model-EK600, UAE) and the required amount of lipid was dissolved in ethanol and mixed systematically. After mixing all the ingredients, an adequate amount of water was added. Then feeds were formulated as pellet form by machine and dried under sunlight. The feeds were allowed to store in the plastic bag in airtight condition. The brood fish were fed twice daily, Once in the early morning time and then in the evening time. Feed was supplied near the shelter made for the fish. The unused foodstuff, debris and feces were removed by siphoning method on a daily basis. Sampling was done monthly for examining the GSI. During sampling selected fish from each cistern was caught with the help of a scoop net after lowering the water level. Then the weight of each fish was taken with a 3 digit sensitive electric balance (AND-GULF, Model-EK600, UAE). For the estimation of gonadosomatic index, 8 fish from each cistern were taken. The weight of each fish was recorded. The fish were dissected and ovaries were then weighed and gonadosomatic index was calculated by using the formula: GSI = (gonad weight/body weight) × 100. Selected broodfish were kept in the tank for about 6 hours for conditioning prior to injection with PG (Pituitary Gland) extract. Handling and carrying of fish were done very carefully to avoid possible injury and secondary infection. Male and female fish were kept in separate tanks and constant water flow was maintained to ensure proper aeration. In induced breeding of M. cavasius, pituitary gland (PG) solution was used as an inducing agent. The females were given an injection of 6 mg PG/kg body weight and the male was given an injection of 2 mg PG/kg body weight as 1^st dose. After 6h, the second dose of PG was given in 6 mg PG/kg body weight of females and 2 mg PG/kg body weight of males. Eggs were collected from the injected female through gentle pressure on the abdomen and milt was collected by sacrificing the injected male. Eggs and milt were gently mixed with the help of feather for fertilization. Fertilized eggs were collected and transferred and spread as homogenously as possible on trays (101.6 × 40.6 × 12.7 cm³). Fertilized eggs in trays received a gentle shower. The eggs are placed on a sieve for assessment of the hatching rate.

Source of Information: Asian J. Med. Biol. Res. December 2020, 6(4): 641-649

Article Link (Online Journal): DOI: https://doi.org/10.3329/ajmbr.v6i4.51230

Funding Source:

Budget:

Total Budget (Tk.) :

Achievement/Findings:

Adverse climatic effects like pollution, degradation and decline of wetland resources and application of pesticides are the reason behind the production of poor quality fish seed and extinction. For enhancing production and restricting resources declining, development policy must be undertaken to prioritize the improvement of biological management and application of synthetic hormone. The great influence of bio-functional compounds like PUFAs on the improvement of fish’s reproduction is well documented As the main source of n-3 fatty acids is the marine environment, it is difficult to make them available for freshwater teleosts. Squid is considered bycatch and is of no use in our country, are used n-3 fatty acids source in this study.

Knowledge Management: Journal