The farmed shrimp market has been growing for over 20 years, with 85% of volumes coming from aquaculture (1). This type of farming is now also expanding in Europe. One obstacle to rearing juvenile Penaeus vannamei shrimp is the farmer’s ability to monitor the growth of his animals and thus optimise zootechnical performance (WG , FCR…) . From time to time, h atcheries can deliver batches composed of non-homogeneous animals to fattening farms and research centres . In order to limit this variability for production or trials, the use of a passive sorter is a solution that limits handling and therefore maximizes animal welfare. To develop this type of sorter, it is necessary to better know the possible relationships between different parts of P vannamei physiognomy.
Materials and methods:
Biometrics were carried out on juvenile P. vannamei shrimp taken from different batches reared at an experimental station (Halieutica, France) soon after deliveries .
The following parameters were recorded:
Results:
The measurements carried out to date enable us to identify some strong and logical trends. Length is strongly correlated with mass (corr=91%, R2=0.87). Width (the most important parameter for the sorter) is correlated with mass (corr=88%, R2=0.78). The length*width index is strongly correlated with mass. This correlation is more interesting than that between length and width and mass individually, as it is much stronger (corr=0.99, R2=0.98).
Discussion:
These measurements enable us to determine the characteristics of the passive sorter . First prototypes are currently tested . Different version of this new tool is under calibration for shrimp weighing less than 3 g.
(1) FAO, EUMOFA 2017/2020