Why do we need selective breeding of indigenous shrimp species in India?

Shrimp Aquaculture – Salient features (2016-17)

• Shrimp aquaculture production (572000 MT); second position.
• Seafood exports (1.1MMT; 5.78 billion USD; 38% vol. & 65% value from shrimp.
• First in shrimp exports: 0.434MMT; 3.726 billion USD; 75% from culture.
• Number of shrimp hatcheries :>560;
• Shrimp seed production: 54 billion.

Typical features of Indian Shrimp Aquaculture

1) Diseases

WSSV, White Faeces Syndrome, EHP, Running mortality.

2) Biosecurity: difficult to practice?

• Highly fragmented (shrimp farming).
• Creek-based & inland.
• Limited infrastructure & old (intake & drain often same).
• Despite the standard practices (Certified stocks, Quarantine, Physical barriers,
• Water treatment, Use of SPF broodstock) we still have diseases.

3) Traditional culture belts.
4) Temperature.
5) Import of broodstock (TINA situation).
6) Plan B (lack of it).

Traditional Belts

1. Area: (approx.) 50,000 ha = >25%
2. Species: P.monodon (broodstock from wild; could be carrying virus).
3. Productivity low.
4. % Survival: Less than 25%.
5. Scope for 3-4x increase in profits if we could introduce P.monodon and P.indicus that are selectively bred.

High Temperature

1. P.vannamei not comfortable >32-33ºC.
2. Pond water temperature reaches >37ºC.
3. Growth, FCR affected.
4. Running Mortality Syndrome (RMS).
5. RMS not common with P.monodon & P.indicus.
6. Temperature tolerance – heritable?!

Broodstock Imports – Risks

1. Dependence on the external source (TINA situation):
2. Business risks
3. Biological risks
4. Right now facing difficulties in:
5. Supply
6. Price
7. Logistics
8. Customs duty
9. Receiving
10. Transport mortalities

Why selective breeding of indigenous species

1)Addressing Indian situation effectively

• Emerging diseases?!
• Bio-security?!
• Traditional culture belts (>25% area).
• Temperature.
• Broodstock import: Business & Biological risks.
• Plan B: Selective breeding of indigenous species.

2)Benefits of selective breeding

• Growth, disease resistance
• SPF/ SPT etc.

3)Cost, availability, bio-security, traceability.

Indigenous species – advantages

• Growth – comparable or even better?!
• Robustness (against environmental stress and diseases).
• RMS – not common in P.monodon, and P.indicus.
• White Faeces Syndrome: P.indicus – less susceptible.
• IHHNV: P.indicus and P.merguiensis refractory .
• P.monodon is reported to be refractory to TSV, IHHNV and less susceptible against EMS.

Distribution,  Fishery:

P.monodon:

Largest species among the penaeids.
Distribution: Indo-pacific.
Fishery: ~2.8% of the prawn catch (1990’s).

P.indicus:
Distribution: Indo-Pacific.
Fishery: ~7.4% of the penaeid shrimp fishery 1980’s).

P.indicus domesticated : Performance summary

• Domesticated stock: Female abw of 30g.+ (minimum 27g.) ;
• Broodstock pond DOC 250 good for maturation.
• Productive 7-15days.
• Mating natural, no AI.
• A male: female ratio of 1:1.
• Eggs per spawn, Nauplii per spawn and %Hatch less (compared to that of wild stock); scope for improvement .
• Spawn per female : >1(F6).
• Nauplii per gram female :improved from 210 to 1047 in 6 generations (F1 – F6).
• Potential for nauplii per gram female reaching 2000 or more (comparable to wild P.indicus) to be explored.
• Farm performance: scope for improvement; ADG of 0.125 – 0.137g. (in 5 crops) with an average gain of 3.6%/year in ABW(17.5 to 19.2g.) with the seed from 3 generations (F0 – F3).

Data on domesticated P.monodon

P.monodon performance highlights

• 200 females 100 days
• 1035 spawns
• 170 million nauplii
• All production through AI.
• 6.4 spawn per female

P.monodon domesticated : Performance summary

• Female abw 80g.+ Ok; BSP DOC 300+ good.
• Broodstock productive for 3 months; quality of male deteriorated after.
• Natural mating zero; hence artificial insemination (AI).
• A male: female ratio of 1:1insufficient; (male 3 to 4 times).
• Fecundity (eggs per spawn) and nauplii per spawn less (approximately 2.5 – 4 times); scope for improvement here.
• Spawn per female :6.4), 5 – 6 times more than wild stock.
• Potential for nauplii per female reaching 3 million or more!
• Farm performance: Good; still scope for improvement; current ADG of 0.27g. (domesticated); compares better to the seed from wild broodstock (0.24g.).

Summary

Selective breeding of indigenous shrimp species is recommended for the following reasons:

• Have clean stock to begin with: DIFFICULT TO FIND CLEAN STOCK FROM NATURAL COLLECTION; helps prevent RECYCLING OF VIRUS.
• Have domesticated, SPF and better-growing stock of indigenous shrimp species, possibly with disease tolerance.
• Productive utilization of traditional shrimp culture belts of WB, Odisha, Kerala and Karnataka.
• Reduced dependence on import of broodstock.
• Have an effective alternative, in the indigenous species P.monodon and P.indicus to supplement P.vannamei .
• Considering the huge investments required, long gestation period, and developmental nature of the project, it is good if government/large integrated private sector companies takes initiative in domestication and selective breeding projects for P.monodon and P.indicus.

We are late in realizing the potential of indigenous shrimp species P.monodon and P.indicus through selective breeding; better late than never!

 

 

 

Source : Society of Aquaculture Professionals (SAP)