Pollution caused by feed not eaten is a major concern for shrimp farmers. Madhusoodana Kurup, professor at Cochin
University of Science and Technology, Kerala, used a technology to convert these leftovers into protein-rich feed. Sumana
Narayanan understands how this benefits farmers
On why left-over feed is a problem
For healthy growth, shrimp need 45 per cent protein in their feed. But 60-70 per cent of it remains unconsumed and accumulates in the pond bed.
This converts into nitrite, a toxic compound and makes the shrimp vulnerable to diseases.
About the technology
We used bioflocs, which is a collection of algae and bacteria found naturally in shrimp farms, to recycle the feed not eaten and fish excreta. By
aerating the water, we encouraged the growth of bacteria, which in turn converted the nitrogenous waste into microbial protein. This protein is a
natural food for shrimp.
On how it works
To produce microbial protein bacteria also need carbon, which they derive from carbohydrates. Farmers can use tapioca, wheat, rice, potato or
yam flour as a cheap and good source of carbohydrate. The optimal carbon-nitrogen ratio should be 1:20.
On economical advantages
Since shrimp feed with high protein content is expensive, the technology will help shrimp farmers switch to feed with less protein content, without
compromising on growth and production. Natural recycling of the waste material also helps farmers save on expenses involved in the water
treatment.
We are a voice to you; you have been a support to us. Together we build journalism that is independent, credible and fearless. You can further help us by making a donation. This will mean a lot for our ability to bring you news, perspectives and analysis from the ground so that we can make change together.
.png)
Comments are moderated and will be published only after the site moderator’s approval. Please use a genuine email ID and provide your name. Selected comments may also be used in the ‘Letters’ section of the Down To Earth print edition.