There are no specifically formulated dry foods for tench (Tinca tinca
L.), which forces farmers to use diets formulated for other fish species. This has
major drawbacks, such as high mortality, slow growth, and body deformities. A
120 day experiment was performed with five-month-old juvenile tench (initial
mean weight: 0.388 g; total length: 31.78 mm) to evaluate decapsulated
Artemia cysts as a supplement to a dry diet for other fish species. Three
treatments, differing in the daily supplement, were tested: 1,800 freshly
hatched nauplii, 1,800 cysts, and 300 cysts per g of tench biomass. Final
survival ranged between 95.3% and 97.9%. Juvenile tench that received the
supplement of 1,800 decapsulated Artemia cysts had a specific growth rate
(1.28), weight (1.83 g), and total length (52.30 mm) significantly higher than
those with the same amount of nauplii. The lowest supplement (300 cysts/g of
fish biomass) allowed significantly lower growth and higher condition coefficient
(1.40) than the rest. Animals with body deformities (1.06%) were only recorded
in the groups that received the lowest cyst supplement. Results showed
Artemia cysts are a suitable dietary supplement for juvenile tench, being an
advantageous alternative to live nauplii.