Seed production and culture of Seed production and culture of Clarias batrachusClarias batrachus

An air-breathing cat fishAn air-breathing cat fish

Dr. I.J. SinghDr. I.J. SinghProf. & HeadProf. & Head

Department of Fishery BiologyDepartment of Fishery BiologyCollege of FisheriesCollege of Fisheries

G.B.Pant Univ. of Ag. & Tech., PantnagarG.B.Pant Univ. of Ag. & Tech., Pantnagar

Air breathing fishes of IndiaAir breathing fishes of India

Common nameCommon name Scientific nameScientific name

MagurMagur Clarias batrachusClarias batrachus

SinghiSinghi Heteropneustes fossilisHeteropneustes fossilis

Spotted murrel Spotted murrel Channa punctatusChanna punctatus

Stripped murrel Stripped murrel C. punctatusC. punctatus

Giant murrel Giant murrel C. maruliusC. marulius

Climbing perch or KuwaiClimbing perch or Kuwai Anabas testudineusAnabas testudineus

Outdoor cemented tanks used for rearing of Outdoor cemented tanks used for rearing of broodstock of broodstock of C. batrachusC. batrachus

Brood stock managementBrood stock management

Brooders were reared in cemented tanks of 5Brooders were reared in cemented tanks of 5×3×1.25m ×3×1.25m

Stocking density of brooders - Stocking density of brooders - 3 specimen / m3 specimen / m33 area area

Partial pond water was replaced by adding fresh bore Partial pond water was replaced by adding fresh bore well water well water

Brooders were fed with prepared feed containing fish Brooders were fed with prepared feed containing fish meal (75%) and broken rice / rice polish (25%) meal (75%) and broken rice / rice polish (25%)

Feeding rate - 10% of their body weight twice a day Feeding rate - 10% of their body weight twice a day

Broodstock of Broodstock of Clarias batrachusClarias batrachus

Seed production of Seed production of Clarias batrachusClarias batrachus

Inducing hormoneInducing hormone - Ovaprim - Ovaprim

Dose rate:Dose rate:Female- 2.0ml/kg body weightFemale- 2.0ml/kg body weightMale - 0.5ml/kg body weightMale - 0.5ml/kg body weight

Pairing ratio of Female & Male – Pairing ratio of Female & Male – 1:11:1

Latency periodLatency periodC. batrachusC. batrachus generally do not release eggs itself even generally do not release eggs itself even after introduction of inducing hormone but become ready after introduction of inducing hormone but become ready to release eggs by stripping after about 24-28hrs to release eggs by stripping after about 24-28hrs

Mature female of Mature female of C. batrachusC. batrachus

Exposed testis of mature male of Exposed testis of mature male of C. batrachusC. batrachus after after dissection dissection

Maceration of extricated testis of Maceration of extricated testis of C. batrachus C. batrachus for for preparation of miltpreparation of milt

Stripping of ovaprim injected female of Stripping of ovaprim injected female of C. batrachusC. batrachus

Fertilized eggs of Fertilized eggs of C. batrachusC. batrachus

Fertilization and hatching Fertilization and hatching

Fertilization rate – 56 – 68% (in dry fertilization)Fertilization rate – 56 – 68% (in dry fertilization)

Hatching rate – 40 to 96% Hatching rate – 40 to 96%

Hatching period - 24 to 26 hrs Hatching period - 24 to 26 hrs

Yolk resorbtion time 5 days Yolk resorbtion time 5 days

Yolk laden hatchlings of Yolk laden hatchlings of C. batrachusC. batrachus

Yolk laden hatchlings of Yolk laden hatchlings of C. batrachus C. batrachus (Close-up) (Close-up)

Larval rearingLarval rearing

On 6On 6thth day larvae were transferred to tanks of day larvae were transferred to tanks of 2 × 1 × 1 m2 × 1 × 1 m size size

Stocking rate of larvaeStocking rate of larvae- 50 larvae/ tank - 50 larvae/ tank

Larval feeding-Larval feeding- Natural food – ZooplanktonNatural food – ZooplanktonArtificial feed- Egg powderArtificial feed- Egg powder

Feeding scheduleFeeding schedule – 4 times daily – 4 times daily

After two months finely ground fishmeal and broken rice in the After two months finely ground fishmeal and broken rice in the ratio of ratio of 3:13:1 was also given was also given

Fry of Fry of C. batrachusC. batrachus

Fingerling of Fingerling of C. batrachusC. batrachus

Three month old fingerling of Three month old fingerling of C. batrachusC. batrachus

Aeration of fry rearing tankAeration of fry rearing tank

Length – weight of fry and fingerling of Length – weight of fry and fingerling of C. batrachus C. batrachus produced produced by induced breeding in June and July, 2003 by induced breeding in June and July, 2003

Days June, 2003 July, 2003

Length (cm) Weight (g) Length (cm) Weight (g)

Range Average

Range Average Range Average

Range Average

15 days 1.5-3.0 2.0 0.025-0.159 0.065 1.1-1.8 1.4 0.010-0.033

0.020

30 days 1.7-6.9 4.0 0.033-0.488 0.185 1.5-2.7 2.4 0.017-0.132

0.085

45 days 4.6-11.1 6.2 0.486-10.581 2.095 1.6-5.9 3.3 0.032-1.978

0.959

60 days 5.7-15.6 8.8 1.906-16.988 5.955 2.4-7.6 4.4 0.111-3.735

1.329

75 days 8.4-17.3 10.9 4.528-19.302 10.767 2.8-9.5 5.6 0.969-7.722

2.373

90 days 12.2-19.5 13.4 11.956-54.188

19.103

105 days 14.6-21.9 17.1 22.0-84.0 39.833

Culture AspectCulture Aspect

Pond preparation Pond preparation Preferable pond size is 0.1 to 0.2haPreferable pond size is 0.1 to 0.2ha

Can be cultured in derelict pondsCan be cultured in derelict ponds

In case of perennial shallow ponds – mahua (mustard) In case of perennial shallow ponds – mahua (mustard) oil cake @ 25 kg/ha/m should be applied to kill oil cake @ 25 kg/ha/m should be applied to kill unwanted fishesunwanted fishes

If pond bottom silt is very heavy- Lime @ If pond bottom silt is very heavy- Lime @ 200-300kg/ha should be use to reduce toxic effect200-300kg/ha should be use to reduce toxic effect

No pond fertilization/ manuring is requiredNo pond fertilization/ manuring is required

If problem of ammonia content, algal bloom occurs – If problem of ammonia content, algal bloom occurs – stop feeding and apply KMnOstop feeding and apply KMnO44 @ 300 ppm. @ 300 ppm.

Stocking density - 4-6 fry/mStocking density - 4-6 fry/m2 2 or 40,000 – 60,000/ ha or 40,000 – 60,000/ ha

Feed - fish meal (75%) and Feed - fish meal (75%) and

broken rice / rice polish (25%) broken rice / rice polish (25%)

Feeding rate - 4% of their body weight Feeding rate - 4% of their body weight

Feeding schedule – Twice a dayFeeding schedule – Twice a day

Growth rate – 150-200gm in one yearGrowth rate – 150-200gm in one year

Production – 4 tonnes/ha/yrProduction – 4 tonnes/ha/yr

Eight months old grow outs of Eight months old grow outs of C. batrachusC. batrachus