The marine shrimp aquaculture industry, in particular the whiteleg shrimp Litopeneaus vannamei, has experienced exponential technological development, with different production systems worldwide. Shrimp farming is made up of several stages and transitions that represent stressful events for the animals, which have a direct effect on reducing appetite and feed intake. Appetite is regulated by various factors as shrimp has a highly developed and sensitive sensory system, and appetite messages are known to reduce stress messages. In this context, modulating shrimp appetite can have a positive effect on stress reduction. A trial was conducted to evaluate the effect of a neurosensorial feed additive (NFA) on shrimp stress reduction through feed intake.
During 8 weeks, 900 Pacific white shrimp (Litopeneaus vannamei) with an average initial weight of 0.5g were divided into 18 ponds of 220L in brackish water with 15 ppt salinity. Faecal matter was siphoned daily, and 60% of the water was changed every third day. The balanced feed used had a protein content of 35% and 7% lipids. The feed was distributed to the shrimp 4 times/day. The NFA was applicated at a 3kg/T rate. Each treatment was replicated 4 times. Feed intake rate, live weight, survival rate, and total biomass were measured at the end of the experiment (week 8). To measure stress reduction, an acute stress induction protocol was started at week 4.
The use of the NFA led to a global improvement of survival rate, from 44 to 62% (Fig.1). After the stress induction protocol, it was observed that immobility time was reduced from 25 to 5 seconds with the NFA. These results suggest that a neurosensorial product have a beneficial effect on stress and mortality reduction in shrimp