Modeling Lactation Curves of Turkish Saanen and Bornova Goats

Modeling of individual lactation curves for milk production in a population of Alpine goats in Cuba

“…The analyses of the relationship between the mathematical properties of the model and the lactation pattern have been focused on the possibility of the model to fit itself to that standard behavior and all models that have been proposed are capable of fitting to the average pattern with high levels of accuracy. However, the models are able to represent other shapes, but they have scarcely been considered (Macciotta et al, 2005;Takma et al, 2009). This is true for general models such as Legendre 0 s orthogonal polynomials, but this is also valid for equations specifically designed to model the lactation curve, as Wood (1967) and Wilmink (1987).…”

“…These criteria for selecting the best model often neglect the statistical or biological problems that may be occurring when the fitting is extended to individual lactations, which can lead to unrealistic estimations of parameters (Faro and Albuquerque, 2002), or the models are too complex for routine use outside research and some of the mechanisms represented are not yet well understood (Fathi Nasri et al, 2008). In order to change the characteristics of the lactation curve it is necessary to estimate genetic parameters obtained from individual curves (Takma et al, 2009), for example, using test-day models with random regression (Dzomba et al, 2010;Mené ndez-Buxadera et al, 2010). The individual variability aspect is a key to being able to extend predictions from the level of the individual to the level of the group performance (Puillet et al, 2011).…”

Characteristics of Lactation Curve in Damascus Goats in Jordan

“…Thus, it is important to determine whether or not these are genetic differences among shapes of the curves. It might be necessary to consider those differences into account for genetic evaluation and selection (Takma et al, 2009). On the other hand, improvement of the genetic models for evaluation of milk yield has produced new characteristics describe shape of the lactation curve ( Pala and Savas, 2005) and can be used as selection criteria (Togashi and Lin, 2004), and are becoming of interest for genetic evaluations based on test day models (Andonov et al, 2007).…”

Effect of soybean hulls on lactation curves and the composition of goat milk

“…By evaluating the lactation curves of Saanen goats through Wood's nonlinear model, Takma et al (2009) showed that the increased rate of yield until lactation peak was 0.13 and Gomes et al (2014) showed a range from 0.03 to 0.13. Nevertheless, in this research, the rate of yield increased from 0.18 to 0.24, which agrees with Zambom et al (2005), who found values ranging from 0.10 to 0.27, and Tufarelli et al (2009), whose values ranged from 0.21 to 0.29 for the increased rate of yield until lactation peak.…”

“…Macedo et al (2001), studying crossbred Saanen goats, concluded that Wood's nonlinear model was the best to describe the lactation curve because it showed less variance than the other models tested. Takma et al (2009) concluded that Wood's nonlinear model can be used to describe the goat yields.…”