“If zebrafish are to be a good research model, and if we want to compare the results, we will have to develop a standard diet for these fish,” says NIFES Mari Moren, head of research.

The zebrafish is being increasingly used as a model in medical and nutrition research, and to help us to understand the consequences of pollution. NIFES scientists have analyzed four different types of zebrafish feed that are currently on the market, and have identified important differences among them, for example in their iron and vitamin C content.

“We have observed aspects that are less than ideal and that will affect the health of these fish. In one case, the zebrafish would get 20 times as much iron as they need and nearly no vitamin C. This is a toxic level for other fish species and will most likely be toxic for zebrafish too,” says Moren.

A diet with too much iron and not enough vitamin C creates an imbalance that can compromise the health of the fish. This may give inaccurate results in experiments where one wants to understand how various diseases and contaminants affect fish. Poor health can aggravate or mask the effects of drugs and diseases.

“It is essential to standardise the diet, which should be possible using the vast knowledge on fish nutrition that we already have,” said Moren.

Source: Penglase, S., Moren, M. and Hamre, K. 2012. Lab animals: Standardize the diet for zebrafish model. Nature: Correspondence 491: 333.