# Rearing Conditions and Automated Feed Distribution Systems for Zebrafish (_Danio rerio_)
## 6 Conclusions and Future Challenges  
When analyzing aspects of fish nutrition, such as those related to the effects of diets, nutrients, molecules, etc., it is not easy to generate highly significant datasets; this is often due to the absence of common and standardized rearing and feeding conditions for the raised animals. The intensive and increasing use of zebrafish as a well-established animal model in many different fields of the biological, biomedical, toxicological, and environmental research thus makes necessary the development and implementation of new automated systems that allow one to obtain as highly controlled rearing and feeding conditions as possible, and, in parallel, to reduce human labor and remove human errors.  
To date, the standardization of rearing and feeding protocols by adopting semi-automatic, automatic, or even robotic feed distribution solutions is a necessary goal to achieve in zebrafish nutritional research. The improvement of these technologies in conjunction with research laboratories and industry, combined with the thorough comprehension of the regulatory networks supporting the alimentary function(s), on one hand, and to the optimal formulation of experimental and commercial feeds, on the other, will significantly extend the potentialities of the zebrafish as a tool to evaluate the effects of diets, dietary components, ingredients or single nutrient molecules, and to test novel hypotheses in nutrigelomics, nutrigelentics, and nutritional physiology.  
Conceptualization: G.D.V., A.B., I.R. and T.V.; methodology: G.D.V., R.S., G.F., T.S., S.F. and M.G.A.B.; formal analysis: G.D.V., A.B., A.S.G., A.M., R.S. and G.F.; writing--original draft preparation: G.D.V., A.B., A.M., R.S. and T.V.; writing--review and editing: G.D.V., A.B., A.S.G., R.S., G.F., I.R. and T.V.; supervision: [PERSON] and T.V.; funding acquisition: G.D.V., T.V. and I.R. All authors have read and agreed to the published version of the manuscript.  
This work was supported by the Italian Ministry of University and Research (\"_Dottoro innovativo con Kantetzzazione industriale_\" Borsa PON 2014-2020 Ricerca e Innovazione, cod. DOT1412034) (GDV, TV). The work was also supported by Research Council of Norway, Grant Number 309368 ExcelAQUA 2.0 (IR).  
Not applicable.  
\begin{table}
\begin{tabular}{c c} \hline \hline
**Automated Feeding System** & **Description** \\ \hline [PERSON] et al. [81] & A self-feeder system with an infrared photocell acting as a food-demand sensor (high costs). \\ \hline [PERSON] and [PERSON] [87] & A small and practical pneumatic device delivering food (low costs). \\ \hline [PERSON] et al. [84] & A semi-automatic dispenser for solid and liquid food (low costs). \\ \hline [PERSON] et al. [89] & An open-source semi-automatic feeding system for dry and live food (low costs). \\ \hline [PERSON] et al. [90] & An automatic feeding system coupled with an EthoVision video-tracking system (high costs). \\ \hline [PERSON] et al. [91] & An automatic feeder of precise amounts of foods (low costs). \\ \hline [PERSON] et al. [92] & A fully automated solution which provides standardized amounts of diets (high costs). \\ \hline [PERSON] and [PERSON] [93] & A robot able to deliver multiple dry and liquid diets (high costs). \\ \hline \hline \end{tabular}
\end{table}
Table 3: Summary of automated feeding systems for zebrafish.  
Data Availability Statement: Not applicable. Conflicts of Interest: [PERSON], [PERSON], [PERSON] and [PERSON], who co-authored this manuscript, are from Tecniplast S.P., which is the company that commercializes the Tritone robotic system described in the manuscript. This is clearly stated in the affiliations' section.