Why not just take a reading as the cow enters or leaves the parlor?
Mainly two reasons: 1) It is beneficial to also get data on cows that are not currently going through the parlor (e.g. far-off, close-up, and hospital pens). 2) Taking temperatures once or twice per day is not sufficient when you consider that the cow may be drinking around the time they go to the parlor (the temperature of the drinking water is much lower than a cow’s core temperature).
