Evaluation of the use of sand substrate in ripening tanks of the pink shrimp Farfantepenaeus paulensis (Pérez-Farfante, 1967)
Under laboratory conditions, shrimp breeders are generally kept in hard bottom tanks (concrete or fiberglass). This practice, however, can affect the reproductive performance of the pink shrimp Farfantepenaeus paulensis due to the strong burial habit that this species presents. In view of this, wild breeders were kept for 50 days in maturation tanks with and without sand substrate and evaluated for their reproductive performance, body physical condition and biochemical composition of tissues (hepatopancreas and ovary), hemolymph and eggs. After seven days of acclimatization, the adults captured on the coast of Santa Catarina were distributed at a density of 7 / m² (male: female ratio of 1: 1.3) in tanks with 10 m2 of bottom area and the females underwent unilateral ablation of the eye peduncle.No significant differences were observed in terms of reproductive performance, although the females in the hard bottom tank had a higher number of spawning and, consequently, more eggs. This trend was not maintained in terms of production of nauplii, since the shrimp in the tank with sand substrate had fertilized spawning throughout the experiment, unlike the rigid bottom tank, which had fertilized spawning only in the first 15 days of the experiment. These results indicate a possible relationship between the type of substrate and the success of copulation of this species in captivity. The body condition of the males improved at the end of the experiment regardless of treatment. In turn, females kept on a rigid bottom worsened their body condition,while those in the substrate tank maintained their physical conditions and showed greater survival. The results of biochemical analyzes of tissues, hemolymph and eggs did not show significant differences between treatments. Although it does not significantly affect the biochemical composition and performance of the breeders, the use of sandy substrate in maturation tanks resulted in increased survival and better body condition for the females. Additionally, an increase in copulation success was observed. The results of this study recommend the use of sandy substrates in the maturation tanks of F. paulensis, although this may mean greater difficulties in the selection of mature females and in cleaning the tanks.