Did you, at any time, give this calf milk replacer? If not, that is probably a good part of why she died. Powdered milk is not suitable for raising calves because it does not have the proper formulation of vitamins, minerals, protien and fat needed for health and growth. The scours did not help her chances of survival, either, but with proper feed she probably would have gotten over the scours. You don't mention what type of scour pills you used, but are you sure they were only supposed to be given once a day? Generally speaking, scour treatments are usually given twice a day. Scours don't have to be 'very bad' to kill a calf of this age, the dehydration as a result of scours messes up the metabolic balance of essential elements (potassium is a big one because it plays a pretty major role in regulating heartbeat), and can cause systems to shut down because of it. Electrolytes will rehydrate and help maintain a proper metabolic balance, but they have to be given on a regular basis, and some brands of electrolytes cannot be given in conjuction with milk. Unless there was some type of secondary infection, LA200 is generally ineffective against most scours because scours are usually caused by a virus or a parasite - the only exception to that (that I can think of) being e-coli which is a bacterium. I don't mean to come down on you, but why did you not find out how to feed this calf before you bought her? And why did you not call the vet when she was not making any progress?