HELLO POND - TRIALLING A FLAVANOID PRODUCT FOR SHRIMP (L.vannamei) UNDER PRACTICAL FARM CONDITIONS.  

Mortality during grow-out, for example that caused by EMS is a major challenge in shrimp farming worldwide. While early stage studies are feasible in lab conditions, possible solutions have to be tried on a pond scale, to involve the complex biome found in grow-out ponds. The goal of our research and development efforts was, to support immune defence of Pacific White Shrimp via nutrition. In laboratory experiments positive effects of a feed additive rich in specific flavonoids (Anta®Ox Aqua from Dr. Eckel, Germany) were already proven (Gessner et al. 2012, 2013; Fiesel et al. 2014; Niyamosatha et al. 2015). In a pond trial lead by Kasetsart University these results have now been confirmed for realistic farming conditions in Thailand. All groups where fed with commercial pelleted feed for white shrimp. Ponds of the treatment group received feed with the botanical feed additive at a concentration of 800 ppm via the feed. Performance parameters were measured, followed by microbiological, histological and immunological analyses.

In the treatment group a significant reduction of the  bacterial load was detected: Total bacterial load was reduced by 90%, total Vibrio counts by 87% and Vibrio parahaemolyticus counts by 90% (Fig. 1). Hepatopancreas samples of the control group had 20% to 80% necrotic cells, typical for EMS. In contrast, shrimp of the treatment group showed no signs of atrophy and bacterial infection and appeared healthy and vigorous. Furthermore, the lower bacterial infection in the treatment group accounted for better survival rate (91% vs. 63%). This improved total biomass production group during grow-out as well as feed conversion ratio (1.35:1 vs. 1.55:1).

In summary a low dosage specific flavanoids complex can improve health and performance of pacific white shrimp in ponds, similar to improvements previously only proven in lab conditions.