Milking system, comprising a milking means (2, 11, 12) with a milking control device and arranged for milking milk from a dairy animal, a milk line (3, 5) in fluid connection with the milking device, a sampling and analysis device arranged to take a sample of the milk from the milk line and to analyse milk from the sample, wherein the milking control device is arranged to control the milking based on a result of said analysis, wherein the sampling and analysis device comprises: - a reagent carrier, comprising a base tape layer with a first side and an opposite second side, to which first side there is provided a reagent in the form of a reagent pad that is arranged to provide a detectable response in the presence of at least one substance in the milk from the sample, - a dosing device (29, 41) arranged to provide a droplet of said milk from said sample onto the reagent pad, - an optical radiation source for emitting optical source radiation onto the reagent pad, and - an optical sensor device arranged to detect optical response radiation emitted by the reagent pad along an optical path to the optical sensor and in response to said emitted source radiation received by said reagent pad, and to analyse the detected optical response radiation to provide an indication of a presence or concentration of said at least one substance in said droplet, wherein the base tape layer is transmissive to the optical radiation, and wherein the first side faces away from the optical path to the optical sensor device during analysing by the optical sensor device, wherein the base tape layer, during analysing by the optical sensor device, is provided substantially horizontally characterised in that during analysing by the optical sensor device the reagent pad faces downward. wherein the sampling and analysis device comprises: - a reagent carrier, comprising a base tape layer with a first side and an opposite second side, to which first side there is provided a reagent in the form of a reagent pad that is arranged to provide a detectable response in the presence of at least one substance in the milk from the sample, - a dosing device (29, 41) arranged to provide a droplet of said milk from said sample onto the reagent pad, - an optical radiation source for emitting optical source radiation onto the reagent pad, and - an optical sensor device arranged to detect optical response radiation emitted by the reagent pad along an optical path to the optical sensor and in response to said emitted source radiation received by said reagent pad, and to analyse the detected optical response radiation to provide an indication of a presence or concentration of said at least one substance in said droplet, - a reagent carrier, comprising a base tape layer with a first side and an opposite second side, to which first side there is provided a reagent in the form of a reagent pad that is arranged to provide a detectable response in the presence of at least one substance in the milk from the sample, - a dosing device (29, 41) arranged to provide a droplet of said milk from said sample onto the reagent pad, - an optical radiation source for emitting optical source radiation onto the reagent pad, and - an optical sensor device arranged to detect optical response radiation emitted by the reagent pad along an optical path to the optical sensor and in response to said emitted source radiation received by said reagent pad, and to analyse the detected optical response radiation to provide an indication of a presence or concentration of said at least one substance in said droplet, wherein the base tape layer is transmissive to the optical radiation, and wherein the first side faces away from the optical path to the optical sensor device during analysing by the optical sensor device, wherein the base tape layer, during analysing by the optical sensor device, is provided substantially horizontally characterised in that during analysing by the optical sensor device the reagent pad faces downward.