Selection of models of lactation curves to use in milk production simulation systems

Author:

Cunha Daniel de Noronha Figueiredo Vieira da1,Pereira José Carlos1,Silva Fabyano Fonseca e1,Campos Oriel Fajardo de2,Braga José Luis1,Martuscello Janaina Azevedo1

Affiliation:

1. UFV

2. PESAGRO-RJ

Abstract

The objective of this study was to select models of lactation curves with a better adjustment to the observed data in models of milk production simulation systems. A data base on 6,459 recordings of daily milk production was used. These data were obtained from monthly and fortnightly controls of milk between 2004 and 2007, from 472 lactations of animals from ten different milking cow herd farms. Based on rolling averages of milk production (MP-L/day) per cow, the ten herd farms were divided into low (L < 15), medium (15 <M < 20) and high (H > 20). Data were also divided according to the lactation numbers in first, second, third or greater. Eight lactation curve models commonly used in literature were compared. The models were individually adjusted for each lactation. The goodness of fit used for comparison of those models was the coefficient of determination, mean square error, mean square prediction error and the Bayesian information criterion. The values for the goodness of fit obtained in each model were compared by using 95% probability confidence interval. Wilmink (1987) model showed a better adjustment for cows of the first lactation numbers, whereas the Wood (1967) model showed a better adjustment for cows of the third or greater lactations numbers for the low milk production groups. Wood model showed a better adjustment for all the lactation numbers for the medium milk production group. Dijkstra (1997) model showed a better adjustment for all lactation numbers for the high milk production group. Despite of being more recent, the model by Pollott (2000), mechanist based and with a higher number of parameters, showed a good convergence for the used data.

Publisher

FapUNIFESP (SciELO)

Subject

Animal Science and Zoology

Reference26 articles.

1. The rate of decline of milk secretion with the advance of the period of lactation;BRODY S.;The Journal of General Physiology,1923

2. The relation between the initial rise and the subsequent decline of milk secretion following parturition;BRODY S.;The Journal of General Physiology,1924

3. On fitting curves to lactation data;COBBY J.M.;Animal Production,1978

4. Modeling extended lactations of holsteins;DEMATAWEWA C.M.B.;Journal of Dairy Science,2007

5. A model describe growth patterns of the mammary gland during pregnancy and lactation;DIJKSTRA J;Journal of Dairy Science,1997

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