Abstract: Methods and systems for detecting the presence of irregularities in milk, and for assessing a health state of a lactating mammal, are provided. A sample of milk is illuminated with a light beam. Scattering data resulting from an interaction between the light beam and the sample of milk is collected. The scattering data is processed to detect the presence or absence of light scattered at a predetermined angle relative to a normal orientation, for instance to determine at least one characteristic of the sample of milk. Based on the presence or absence of light, the presence of irregularities in the sample of milk can be determined, for instance to assess the health state of the lactating mammal based on the at least one characteristic of the sample of milk.