Revista Colombiana de Ciencias Pecuarias
Print version ISSN 0120-0690
CASAS, Gloria A; RODRIGUEZ, Daniel and AFANADOR TELLEZ, Germán. Mathematical properties of the Gompertz model and its application to the growing pig. Rev Colom Cienc Pecua [online]. 2010, vol.23, n.3, pp. 349-358. ISSN 0120-0690.
In this study, the Gompertz model is used to describe the changes in chemical components (protein, lipids, ash and water) in growing pigs, as body weigh increases. Growth and changes in deposition of several molecules was evaluated at 10 different ages (1, 21, 63, 99,126,154,175, 210, 239 and 273 days of age) in 39 pigs. Carcass samples, red and white viscera were collected and submitted for chemical analysis. Our study demonstrated that the model parameters have significance and biological sensitivity, which can be interpreted through maturity at 50% and at adult weight. These traits can be used to estimate the effect of environmental factors on growth and adult weight. The 129 g/day protein retention rate found in the present study was 17.3% lower than the rate observed for highly selected genotypes, and it supports the theory that protein retention rates are highly related to daily body weight gain patterns. The studied genotype presented a similar pattern for the dynamics of chemical components as non-selected animals.
Keywords : growth; mathematical modeling; parameterization.