WWW.WAS.ORG • WORLD AQUACULTURE • JUNE 2025 51 Downfall, Production Related and Supply Demand Issues in L. vannamei Farming With increased production the L. vannamei farmers of India gradually started facing carrying capacity issues, and production-related issues such as Vibriosis, White gut and White feces diseases due to high organic loads and poor water quality. Diseases like EHP (Enterocytozoon hepatopenaei), White Spot Syndrome Virus (WSSV), running mortality and Atrophy of hepatopancreas also severely impacted L. vannamei farming in terms of low survival, poor growth performance and crop failures. Additionally, the COVID-19 pandemic impacted world trade, and its negative impacts resulted in reduced prices for shrimp exports, which in turn affected the farm gate price followed by increased costs of production (feed cost, seed cost, labour and energy costs). India was impacted with COVID-19 in March 2020 and the shrimp farming sector was affected in various ways. Shrimp processing businesses faced the possibility of factory shutdowns, cancellations and postponements of purchase orders, and difficulties acquiring raw material as many farmers panicked and harvested their shrimp. Consequently, the price of shrimp fell. SPF broodstock could not be brought in due to the cancellation of overseas flights. Labor issues resulted from a general lack of workers and restricted mobility of skilled labor. Feed movement was restricted, and feed costs increased as a result of a shortages of ingredients. (CONTINUED ON PAGE 52) FIGURE 2. The exotic L. vannamei readily adapted to India’s farming infrastructure. TABLE 1. Salient features of P. Monodon vs L. vannamei farming. Characteristics P. monodon L. vannamei Growth rate Slow compared to L. vannamei, especially This species grows as fast as P. monodon up to 20 grams. (up to 3gm/week) up to 20 grams. After that culture can continue, but growth may be slower. Stocking density Very high stocking densities may require strict L. vannamei is easier to culture with high densities control over pond management practices typically 60-150 pcs/mt2 (up to 400 pcs/mt2) and high risk strategies. than P. monodon which can be aggressive. Salinity tolerance 5-45 ‰ (optimum 10-25‰). 0.5-45‰ (optimum 7-37‰). Temperature In lower temperatures it cannot be grown. Wide range from 15-35˚C (optimum 23-30˚C). tolerance Below 25˚C feeding will slow down. Can grow in lower water temperatures. Dietary protein Require high protein (38%) so F.C.R. Require lower protein (33%) so F.C.R. will be lower requirements will be higher compared to L. vannamei. compared to P. monodon. Disease resistance Highly susceptible to various viral diseases. Comparatively less susceptible to WSSV. This species is refractory to TSV and IHHNV. SPF and SPR against TSV is available commercially. SPF/SPR/SPT varieties not available in market. Survival rate is higher compared to P. monodon. Domestication More difficult. Easy. Gonad develops in earthen ponds naturally. of brooders. Breeding Easier than L. vannamei. More technical compared to P. monodon. Post harvest Handling, transportation and processing Quality degrades without proper care. Meat yield characteristics is easier than L. vannamei. Meat yield is lower is higher (66-68%) compared to P. monodon. (62%) compared to L. vannamei. Marketing Good for bigger sizes. Good for smaller sizes. Origin Local species in Asia. L. vannamei is alien to Asia and importation may cause problems with import of new pathogens.
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