Mathematical formulation of lactation curves

In the present investigation an attempt has been made to study the patterns of milk yield of crossbred cows during lactation, and to find out the optimum number of observations needed for prediction of the total milk yield based on partial data. Wood's model, Morant-Ganasakthy and Mitscherlich x Exponential models have been used for analysis. The selected model 2 explained a larger variation though Morant-Ganasakthy and Mitscherlich x Exponential model performed almost equally well when fitted to individual lactation data, but the selected model gave better estimated value of peak yield and total milk yield. By fitting partial data to the Morant - Ganasakthy model it has been found that 115 to 160 days data can be used to predict the total production during the whole lactation with 2% deviation in total yield.