An important factor facilitating the application of zebrafish in biomedical research is high throughput screening of vertebrate animal models. For example, being able to model the growth of blood vessel in the vasculature system is interesting for understanding both the circulatory system in humans, and for facilitating large scale screening of the influence of various chemicals on vascular development. Compared to other models, the zebrafish embryo is an attractive alternative for environmental risk assessment of chemicals since it offers the possibility to perform high-throughput analyses in vivo. However the lack of an automated image analysis framework restricts high throughput screening. In this paper, we provide a method for quantitative measurements of zebrafish blood vessel morphology since it is difficult to assess changes in vessel structure by visual inspection. The method presented is generalized, i.e. it is not restricted to any specific chemically treated zebrafish, and can be used with wide variety of chemicals.