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Shrimp Culture
Changing the farming model The Gokuldham farm in Gujarat did an infrastructure revamp, involving a four- step water treatment process, frequent sludge removal and a 2-phase nursery system
Nursery ponds and 1.35g juveniles after phase 1 nursery.
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econd generation farmer, Hetal Shantila Patel, had specifically equipped himself with a MSC in Aquatic Biology to enhance his skills in aquaculture management and to take over the family’s company, Mindhola Foods, LLP which focuses on shrimp farming, trading and an export business. He has been farming for 26 years. However, in 2020, he faced issues with diseases caused by the microsporidian Enterocytozoon hepatopenaei (EHP) and white faeces syndrome (WFS); Hetal knew that that he had to change the way of farming vannamei shrimp in his farm. “We just could not continue in the same way. Creeks were contaminated. We had already added a nursery phase in 2016, but this was just not enough. In 2020 we started a two-phase nursery system at the Gokuldham farm. The idea is to reduce the time in the grow-out phase,” said Hetal, during a presentation at the 2-day webinar conducted by the Society of Aquaculture Professionals on “Overcoming the hardships in shrimp farming -Lessons from India” in January 2021. The company has two farms, one of them is the 170ha Gokuldham farm, which has a total of 220 ponds and production in 2020 was 390 tonnes from 34ha.
New model to improve productivity
Key to this new culture model is the refinement of several shrimp farming principles. Among these are clean and clear water, small ponds for easy management, aeration with long arm aerators at 10HP/10,000kg, recirculation to reduce disease risks and wastewater management. “Sludge removal is based on 2-3 hours/100kg of feed and we exchange water at a rate of 3-4 tonnes. We want to reduce any risk from the external environment and so we decided to recirculate water through our reservoirs.” May/June 2021 AQUA Culture Asia Pacific
Hetal Shantila Patel started farming in 1994. Faced with issues of diseases, Hetal knew that he had to change the way of farming vannamei shrimp in his farm.
“Why did I need to restructure my farm? In the Gokuldham farm, in 2016 and 2017, productivity was good. I could harvest 154-159 tonnes from eight ponds at 20-21 tonnes/ ha. But in 2018 and 2019, the situation became bad. In 2018, I harvested only 133 tonnes (17 tonnes/ha) and then in 2019, with 11 ponds, I could harvest only 109 tonnes (13.7 tonnes/ha). Feed conversion ratio (FCR) increased over these years from 1.39 to 1.71. Average survival rates were lower at 83% in 2019, from 96% in 2017. Stocking density was a constant 73-78 PL/m2,” explained Hetal. In 2019, Hetal restructured his farm, comprising eight culture ponds and four nursery ponds. The water area ratio was 70:30 (culture ponds: treatment ponds). But it was not enough, and in 2020, he restructured again, reducing to 40% culture area and 60% water area, i.e. sacrificing culture ponds for water treatment ponds. The previously 1ha ponds with 1.8-2.0m depth were divided into 0.2ha and 1.2-1.4m deep ponds for grow-out and nursery culture.
