| Abstrakt: |
This study investigated the effects of dietary supplementation with chitosan, zinc oxide (ZnO), and chitosan–ZnO nanocomposite on the growth, survival, body composition, digestive enzyme activities, and hemato-immunity of Pacific white shrimp (Penaeus vannamei), alongside its impact on diet economic efficiency. Shrimps with an initial weight of 3.27 ± 0.11 g were exposed to eight diets: a control basal diet without additives and experimental treatments containing 36 mg kg−1 chitosan; 10, 20, and 40 mg kg−1 ZnO; and 10, 20, and 40 mg kg−1 chitosan–ZnO nanocomposite over a 90-day period. Experimental diets led to significant improvements in growth indices; however, the effects of the highest dosages of ZnO and chitosan–ZnO were not significant on specific growth rate and survival rate. The most significant improvements in growth performance and survival rate were observed with chitosan–ZnO nanocomposite at the 10 mg kg−1 dosage. Furthermore, experimental treatments resulted in elevated whole-body lipid and protein contents, as well as heightened activities of protease, amylase, and lipase enzymes compared to the control group. Substantially increased digestive enzyme activities were noted in shrimps fed chitosan–ZnO nanocomposite at 10 mg kg−1 concentration (P < 0.05). In addition, shrimp fed with chitosan–ZnO nanocomposite at 10 mg kg−1 exhibited lower levels of serum aspartate transaminase, alanine transaminase, and alkaline phosphatase, along with higher levels of acid phosphatase compared with the other experimental treatments and control group (P < 0.05). Notably, total and differential hemocyte counts showed a gradual increase from the control group to experimental treatments, peaking with chitosan–ZnO nanocomposite at the 10 mg kg−1 concentration. The findings highlight the potential of bionanocomposites, specifically chitosan–ZnO nanocomposite, in improving shrimp nutrition and subsequently its diet economic conversion ratio as the lowest ECR of 1.3 ($/kg) was observed with chitosan–ZnO at 10 mg kg−1. This study provides valuable insights into sustainable approaches for optimizing the performance of Penaeus vannamei in aquaculture systems. [ABSTRACT FROM AUTHOR] |
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