Datas - Effects of prior familiarisation and MFAA in P. vannamei shrimp

Feeding attractants are often used in aquaculture to enhance feed intake and promote growth. To evaluate their effectiveness, feeding tests must rely on robust protocols that minimise interindividual variability. Prior familiarisation involves repeated exposures to the testing tank to eventually habituate animals to it and redirect their focus toward the tested feed. This study assessed the effects of prior familiarisation on stress responses and feeding behaviour of the Pacific white shrimp Penaeus vannamei, and evaluated its relevance in evaluating the attractivity and palatability of a mix of free amino acids (MFAA). In Experiment 1, we assessed the effects of prior familiarisation (1 h/day for three consecutive days) and the presence of feed during testing. Familiarisation increased feed consumption but had no effect on stress responses. In Experiment 2, we assessed the effects of familiarisation and the presence of several feed types during the test (No Feed, uncoated Blank Diet, Blank Diet coated with 0.5 or 1 % of MFAA). Familiarisation increased feed consumption but did not improve shrimp’s ability to discriminate feeds. These results question the relevance of this time- and resource-consuming procedure in feeding tests. Additionally, shrimp consumed more MFAA-coated feed, regardless of familiarisation, suggesting that palatable additives can mitigate beneficial effects of familiarisation. Behavioural responses were highly variable across both experiments and replicates, highlighting the need for more standardised and refined protocols. Given the economic importance of P. vannamei, refining testing procedures is essential to improve the assessment of additive efficiency.