a compliance study of Bangladesh shrimp aquaculture - The United ...

SerajMinimum Substantive CriteriaBangladesh StatusPresently farmers of all sectors are mostly facing problems withmaintaining good health of their farmed shrimp. They are trying to findways to combat diseases and keep shrimp healthy to grow and have agood harvest.Recently, advanced famers are using control system technology (CST)or Modified Control System Technology (MCST) mainly for diseasemanagement. In CST, the total production process is controlled and themeasures are in place for management of shrimp health and to protectagainst disease. In this process disease-free PL are collected from atrusted hatchery that uses disease-free mother shrimp and tests themthrough Polymerase Chain Reaction (PCR) and maintain the culturecondition free of pathogen. In MCST, disease-free (PCR screened) PLare reared in a controlled nursery for one month thus their resistance topathogens is developed. Then they are released into a grow-out pond.These management systems showed a good harvest for recent years butbecause of additional cost, very few farmers are adopting thesesystems. 1Only aquatic animals that arecertified as healthy and/or free ofserious pathogens should be usedin aquaculture.It is very important that the shrimp PL used in aquaculture are healthyand free of disease. The system to examine the hatchery PL throughPCR prior to stocking them is in place but this facility is very limited inscope and not complete. There are a few facilities offer PCR testing butat a very high cost 2 . The capacity of screening facilities is also a limitingfactor as a large number of PL is produced every year. A very smallproportion of PL are screened for diseases through PCR (not more than1%) 1 .The government of Bangladesh is developing a national shrimp seedcertification system. The project is assisting in establishing a PCR-baseddiagnostic laboratory facility for the Department of Fisheries, incollaboration with the private sector, developing a seed certificationsystem and training of relevant personnel to conduct screening of broodstock and larval stages of shrimp on a regular basis. It is expected thatthe project will result in a fully-functional seed certification system andimprovement of brood stock and PL quality.The process adds cost for the farmer. The farmers also accuse thehatchery owners being reluctant to subject their PL to examination 3 .A healthy culture environment atall phases of the production cycleis necessary to reduce the risk ofaquatic animal disease. Thatincludes thorough preparation ofthe culture facilities beforestocking, maintenance of optimalenvironmental conditions throughmanagement of stocking densities,aeration, feeding, water exchange,phytoplankton bloom control, etc.Routine monitoring for earlydetection of aquatic animal healthproblems.Under the present culture practice, whether extensive or improvedextensive, farmers use preventative measures to protect the farmedshrimp. Farmers prepare their pond by sun drying the bottom once ayear, using lime (Calcium Oxide or Hydroxide) to disinfect andaugment the soil. Artificial feed is used only in golda farms. Use of feedin bagda farms is very uncommon. Stocking density is very low sousually external aeration is not necessary but some advanced farmersuse this facility to keep pond water more oxygenated. Usually waterquality does not deteriorate but farmers examine water parameters suchas pH, dissolved oxygen, salinity etc. and maintain them by using limeor a water exchanging system to maintain salinity.Farmers use a sampling method to monitor growth, survival and diseasecontamination frequently. They cannot detect the disease outbreak earlybecause shrimp diseases are mainly caused by viruses and the outbreakis so rapid that sometimes farmers can do nothing but watch ageneration fail.1 Md. AI Masud, Fisheries Biologist and Shrimp hatchery operator, Khulna, Bangladesh, Personal contact2 Shamsul kabir PhD, Team Leader, PRICE project, USAID, Bangladesh, Personal Contact.UNU-Fisheries Training Programme 37