“…Several parametric models, such as exponential decline function, inverse polynomial function, gamma type function, exponential function, Legendre polynomial function, and mixed log function have been developed to describe the lactation curve in dairy animals (Woods, 1967;Wilminks, 1987;Ali and Schaeffer, 1987;Kirkpatrick et al 1990;Beever et al 1991;Sherchand et al 1995;Grossman and Koops, 1999;Macciotta et al 2005;Vohra, 2010;Macciotta et al 2011;Vohra et al 2011;Prakash et al 2015;Jamuna 2015, Vohra et al 2017Sahoo et al 2018), differing mainly in the type of regression, in the number of parameters and in their degree of relationships with the main features of a typical lactation pattern, such as peak yield, days to attain peak yield, days in milk and persistency. The shape of lactation curve depicted by individual dairy animal is subjected to random variation and different functions vary in their goodness of fit to individual lactations in different species.…”