The increasing market demand for decapods has led to a considerable interest in cultivating decapod species at a larger scale. Following the development of hatchery technologies, most research has focused on the development of formulated feeds for commercially farmed decapods once they enter the juvenile stages. The use of formulated feed for decapods at a commercial scale is still in the early stages. This is probably because of the unique feeding behavior that decapods possess: being robust, slow feeders and bottom dwellers, their feeding preferences change during the transition from pelagic larvae to benthic juveniles as their digestive systems develop and become more complex. The current practice of decapod aquaculture involves the provision of juveniles with food such as natural diet, live feed, and formulated feed. Knowledge of nutrient requirements enables diets to be better formulated. By manipulating the levels of proteins and lipids, a formulated feed can be expected to lead to optimal growth in decapods. At the same time, the pellet’s physical characteristics are important factors to be considered upon formulating commercially farmed decapod feeds, considering the unique feeding behavior of the decapod. However, most published studies on decapod nutrition lack data on the physical characteristics of the feed types. Thus, it is difficult to establish a standard feed formulation that focuses on the physical pellet properties. Moreover, careful consideration must be given to the feeding behavior of species, as decapods are known as bottom feeders and are robust in terms of handling feed. Information on the pellet forms, diet composition, and unique feeding behaviors in commercially farmed decapods is gathered to suggest potential better formulated diets that can optimize growth and reproduction. Thus, the purpose of this review is to summarize the information that has been published to date and to come up with suggestions on ways to improve the feed formulation in decapods that comply with their feeding behavior and nutrient requirements. Further research is needed to explore the potential of the pelleted feed at the adult stage so the decapod can take full advantage of the nutrients present in the pellets.

https://www.mdpi.com/2076-2615/11/6/1761/pdf

Use of Pelleted Diets in Commercially Farmed Decapods during Juvenile Stages: A Review.

Rab9 defense against white spot syndrome virus by participation in autophagy in Marsupenaeus japonicas

/pdf/melanogenesis-its-regulatory-process-and-insights-on-1q2lve6xyh.pdf

Melanogenesis, Its Regulatory Process, and Insights on Biomedical, Biotechnological, and Pharmacological Potentials of Melanin as Antiviral Biochemical

Viral diseases are a serious issue for the shrimp aquaculture industry. White spot syndrome virus (WSSV) has been considered one of the most dangerous pathogens infecting cultured shrimp, causing a mortality rate as high as 100% within 7–10 days of viral infection. So far, several protocols have been applied to protect shrimp against virus attacks, but their protection efficiency is very limited. In this study, for the first time, three melanin-containing feedstuffs (F1, F2, and F3) were formulated and fed to cultured shrimp to investigate the ability of melanin to protect shrimp from WSSV. The obtained results showed that F2 had a protection rate of 64% at day 7 and 62% at day 10 after virus challenge. The protection ability of the feedstuff depended on the amount of melanin consumed by shrimp. Moreover, our results also demonstrated that the transcription level of the VP28 gene, which codes for the VP28 protein, a representative for the presence of WSSV, was significantly decreased in shrimp fed F2. Taken together, our study suggests that melanin-containing diets may be applied in aquaculture to protect shrimp against WSSV infection; further, combined protocols with the simultaneous use of melanin-containing diets and other protectants should be studied and applied to increase the protection efficiency.

/pdf/melanin-containing-feedstuffs-protect-litopenaeus-vannamei-2292jz0760.pdf

Le Dinh Tu

Papers

Melanin-containing feedstuffs protect Litopenaeus vannamei from white spot syndrome virus