Histologia do hepatopâncreas e das gônadas de fêmeas do camarão marinho Penaeus vannamei (Boone, 1931) alimentado com ração contendo aditivos de palatabilidade

Abstract

The consumption of fish as a quality protein source is growing globally due to the increasing population and the search for healthy foods. Shrimp stand out in this context, especially the species P. vannamei, which is adaptable to various farming conditions and has flexible feeding habits. One of the main challenges in aquaculture is the antagonism between growth and reproduction, as animals must allocate energy preferentially to one of these functions. Therefore, understanding the influence of diets on target organs becomes essential. The present study aimed to verify, through histology, the effect of using three different diets with palatability additives (T1, T2, and T3) and to identify possible alterations in the hepatopancreas and gonads, as well as to check the maturation stages and evaluate the health status of the cultured animals. P. vannamei shrimp were distributed among forty tanks (four groups of ten tanks each), at a density of 85 shrimp/m2 and fed four times a day. Each treatment used a different additive, except for the Control group (no additive). The additives were not specified due to commercial ethics. After 81 days, one female from each tank was collected, totaling 40 individuals. After fixation in Davidson's solution and storage in 70% alcohol, the 40 samples were transferred to histocassettes containing 70% ethanol and were processed according to standard procedures for histological analysis, stained with H&E, and examined under a microscope. The E, R, F, and B cells were visibly identified in the hepatopancreas of female P. vannamei, with preserved structural integrity in the tubules, vacuoles, and lumen in all experimental groups. Additionally, the accumulation of lipids in the hepatopancreatic vacuoles suggests that the animals were in an immature stage and that there was no lipidic mobilization to the gonads. Despite the presence of pathogens such as Vibrio spp. and Gregarina sp., no morphological alterations were detected in the hepatopancreas, indicating the functional preservation of the organ. Furthermore, the histological analysis of the gonads indicated gonadal immaturity in all treatments, confirming the juvenile state of the organisms. Given the findings and results obtained, it was concluded that the palatability additives used in the experimental diets (T1, T2, and T3) did not promote morphological or functional alterations in the hepatopancreas, nor did they negatively impact the gonadal development of the evaluated females. Furthermore, the importance of histology as an efficient tool for monitoring the health and nutritional performance of the animals was emphasized, allowing for a better understanding of the physiological particularities of the species and their management in aquaculture.