The estimation of the parameters of the curve,which follows a set of measured daily milk yields of a cow, is obtained according to the method of Marquardt(R Development Core Team, 2011) using non linear regression. The shape of the curve can be recognized on the basis of the signs of the estimated parameters
Modeling lactation curve standards for test-day milk yield in holstein, Brown Swiss and simmental cows (PDF Download Available). Available from: https://www.researchgate.net/publication/285936241_Modeling_lactation_curve_standards_for_test-day_milk_yield_in_holstein_Brown_Swiss_and_simmental_cows [accessed May 2, 2016].