Magur (Clarias batrachus) breeding

Clarias batrachus, commonly known as the walking catfish or Thai catfish, is a species of air-breathing catfish. Here's some information about the reproduction, breeding techniques, hormonal usage, and related aspects of Clarias batrachus:
1. Sexual Dimorphism: Male and female walking catfish can be distinguished based on certain physical characteristics. Males tend to have a larger size, broader head, and more prominent spines on their pectoral fins compared to females.
2. Breeding Conditions: Walking catfish are known to breed during the rainy season or when there is an increase in water levels. They typically prefer warm water temperatures.
3. Spawning Behavior: Walking catfish are nest builders, and males exhibit paternal care. The male constructs a nest by digging a depression in the substrate, often in muddy areas or among aquatic vegetation.
4. Hormonal Induction: In aquaculture settings, hormonal induction is commonly used to synchronize and stimulate breeding in walking catfish. Hormones like human chorionic gonadotropin (hCG), luteinizing hormone-releasing hormone analogs (LHRHa), or synthetic hormone analogs are used to induce ovulation in females and spermiation in males. The dosage and timing of hormone administration depend on factors such as fish size, maturity, water temperature, and breeding objectives.
5. Breeding Tank Setup: Prepare suitable breeding tanks or ponds for walking catfish reproduction. The tanks should have appropriate water conditions, including a temperature range of 25-30°C (77-86°F), pH around 7, and good aeration to ensure oxygen supply.
6. Hormone Injection: Hormonal injection is typically performed on female walking catfish to induce ovulation. The hormone is administered through intramuscular or subcutaneous injections. It is important to handle the fish carefully during the injection process to minimize stress and ensure proper dosage delivery.
7. Spawning Technique: After hormone injection, the female walking catfish is introduced into the male's nest. The male initiates courtship behavior by circling, nudging, and wrapping his body around the female. This stimulates the release of eggs by the female and sperm by the male for fertilization.
8. Nest Construction and Preparation: Male walking catfish construct nests by excavating depressions in the substrate. They may create tunnels leading to the nest for protection. Nests are usually built in shallow waters, often in muddy areas or among aquatic vegetation.
9. Egg Collection and Incubation: Once the eggs are fertilized, they adhere to the nest walls. The male walking catfish guards the nest and ensures adequate oxygenation of the eggs by fanning them with his pectoral fins. During incubation, maintain suitable water conditions and temperature for the eggs to develop.
Larval Rearing: After hatching, the walking catfish larvae have external gills and can breathe atmospheric air. Provide appropriate rearing conditions, including water quality, temperature.

1. MAGUR BREEDING ( Clarias batrachus ) Vishal solanki

2. Scientific classification Kingdom : Animalia
Phylum : Chordata
Class : Actinopterygii
Order : Siluriformes Family : Clariidae Genus : Clarias
Species : Clarias batrachus Scientific name : ( Clarias batrachus )

3. Introduction Magur ( Clarias batrachus ) is a species of freshwater airbreathing catfish native to Southeast Asia. This fish know as walking catfishe because of its ability to walk on land by using pactoral fin movement. This fish normaly lives in slow moving water body or in stagnant water like pond, swamps, sreams , rivers and rice paddies.

4. Geographic distribution Magur is a very distributed fish species from India (east India), Pakistan, Bangladesh, Myanmar, Sri Lanka, Thailand, Singapore, Indonesia, and the Philippines. Its current range includes the United States, where it was first introduced to Florida from Thailand for cultivation purposes.

5. Biological distribution This is airbreathing fish. Here accessory breathing organ is branched and present near the gill. Can be cultured in oxygen-poor water as it is an air-breathing fish important. The head is large and the mouth is present on the ventral side. Of the eighth barbels two are much stouter and larger while others are similar.

6. Cont.. This catfish has long-based dorsal and anal fins, as well as several pairs of sensory barbels, and also lacks an adipose fin. Magur has Pectoral and pelvic fins in paired and dorsal, anal, and caudal fins in unpaired fins. The skin is scaleless, but covered with mucus , which protects the fish when it is out of water.

7. Habits and habitats This species can be found in freshwater, brackish water, and terrestrial environments. It has been recorded at a depth of one meter but the species’ maximum depth is unknown. Clarias batrachus burrows into the mud during cold and dry months to survive poor weather conditions. Clarias batrachus can survive outside of the water and travel on land as long as its gills stay moist. It is most common to see C. batrachus outside of the water after heavy rains.

8. Feeding habits The walking catfish is omnivorous As larvae , C. batrachus feeds entirely on plankton . In the later developmental stage of fry, it begins to prey on larger organisms When it progresses into a juvenile , it predominantly eats insects As an adult , a walking catfish preys on plants (benthic algae), insects (eggs, pupae, or nymphs [e.g., dragonfly nymphs, chironomid larvae]), aquatic worms, mollusks, and smaller fish (finfish) The walking catfish is also a detritivore and eats organic waste. Clarias batrachus has a broad diet and is known to be an opportunistic feeder

9. Economic Importance for Humans: Positive Clarias batrachus is used in commercial fisheries, aquaculture, and aquariums The walking catfish is widely consumed in its native range (Asia) but not in its introduced range Further, Ohio and other U.S. states have limited or prohibited the possession of the walking catfish to prevent its expansion

10. Economic Importance for Humans: Negative The walking catfish poses a threat as an invasive species Clarias batrachus , once introduced, is hard to contain and control due to its mass spawning that produces several thousands of eggs, its voracious diet, and its ability to survive in muddy and low-oxygenated conditions Costly containment methods, such as the use of barrier fences, have been utilized to prevent walking catfish from invading fish stocks

11. Natural breeding of magur Breeding season:- June-August Breeding interval :- Walking catfish breed via multiple spawning cycles during the summer. Range number of offspring:- 7,000 to 9,000 Average age at sexual or reproductive maturity (female)1 year, (male)1 year. Range time to hatching:- 20 to 24 hours Average time to independence:- 72 hours

12. Cont.. The walking catfish fry becomes independent after three days The male guards the nest from predators, immediately following spawning The female will return once the eggs have hatched and the male and female take part in protecting the fry until they are independent The parental investment only extends to 24 hours following the hatching

13. Captive breeding of magur Breeding techniques : the standard breeding technique developed by the Central Indian FisheriesResearch Institute. Selections of brooder : use Magur one year old and weighing about 100 g. each. Identifying brooder : Gravid females are easy to identify as they are comparatively heavier, have a round and bulging abdomen and their vent is more red than that of the males.

14. Cont.. In the female , the genital papilla is short, oval and slit-like; where as in males , the papilla is conical and elongated with a pointed reddish tip. Mature female mature male

15. Cont.. Brood - stock development: brood fish is maintain in cement tanks with soil and running water. Stock brooder in well prepared pond in month of April. Stocking density is 8000 no/ha. The fishes where fed with trash fishes and rice brand at 9:1 proportions at about 10% of body weight. Fish meal, wheat flour and soya cack can be also used in the diet.

16. Cont..

17. Cont … For Induced breeding given singel dose of ovaprim at same time for both male and female. Hypodermic syringes with a small size of needle use to ingect hormones into the muscle of brooder. Kept the treated male and female fishe sapratly In two tank.

18. Cont.. Stripping and fertilization: Earlier, the injected males were sacrificed to prepare sperm suspension in clean water. The testes were dissected out and cut into small pieces with the help of small scissors and a clean blade. A small amount of water to activate the sperm. This sperm suspension can remain dormant and fertile for up to 24 hr. examined the fish for ovulation by hand stripping.

19. Cont.. Fish that yielded a good stream of transparent green-brown eggs were rated as ovulated. released the eggs by gently pressing the abdomen towards the vent, collecting them on a stainless steel plate. The sperm suspension was sprinkled evenly over the eggs and clean water was added. The milt is then added and mixed well with the help of a feather .

20. Cont.. Eggs and sperm were allowed to mix by gently moving the tray for 4-5 minutes. wash the fertilized eggs thoroughly and transferred them to the hatchery before the eggs began to adhere. Removed unfertilized or dead (opaque/white) eggs immediately to prevent The developing eggs are small, adhesive, and are incubated in plastic basins with running water. fertilized the hand-stripped eggs artificially using the dry and wet methods.

21. Reference https://www.researchgate.net/publication/228510216_Seed_production_of_Magur_Clarias_batrachus_using_a_rural_model_portable_hatchery_in_Assam_India-A_farmer_proven_technology. https://www2.slideshare.net/mobile/CREATIVEAvro/magur-fishclarias-batrachus?qid=d40574e3-b0b2-41a1-aa99-51cef937c82c&v=&b=&from_search=1.

22. Reference https://animaldiversity.org/accounts/Clarias_batrachus/. https://www2.slideshare.net/mobile/SaiprasadBhusare/breeding-of-magur?qid=d40574e3-b0b2-41a1-aa99-51cef937c82c&v=&b=&from_search=6. https://en.m.wikipedia.org/wiki/Walking_catfish.

23. Thank you..